WorldWideScience

Sample records for formation linking field

  1. Linking the Scales of Star Formation

    Science.gov (United States)

    Calzetti, Daniela; and the LEGUS Team

    2018-01-01

    Understanding galaxy evolution requires understanding star formation and its dependence on the local environment, spanning the scales from individual stars to kpc–size structures. The physical conditions within galaxies determine the formation of stars, star clusters, and larger structures, and their subsequent evolution. Observations of external galaxies with the HST that include the UV have enabled the characterization of the young stellar populations with unprecedented accuracy and detail, thus aiding the census and description of those populations. We are now in a position to quantify the spatial distribution and clustering of young stars, and investigate the impact and imprint of the physical conditions of both the local and global environment on the formation and evolution of the multi-scale structures. This talk describes the Legacy ExtraGalactic UV Survey (LEGUS), an HST Treasury programs aimed at investigating these issues using multi-color imaging, from the near-UV to the I, of a sample of fifty nearby galaxies.

  2. Correlations between community structure and link formation in complex networks.

    Directory of Open Access Journals (Sweden)

    Zhen Liu

    Full Text Available BACKGROUND: Links in complex networks commonly represent specific ties between pairs of nodes, such as protein-protein interactions in biological networks or friendships in social networks. However, understanding the mechanism of link formation in complex networks is a long standing challenge for network analysis and data mining. METHODOLOGY/PRINCIPAL FINDINGS: Links in complex networks have a tendency to cluster locally and form so-called communities. This widely existed phenomenon reflects some underlying mechanism of link formation. To study the correlations between community structure and link formation, we present a general computational framework including a theory for network partitioning and link probability estimation. Our approach enables us to accurately identify missing links in partially observed networks in an efficient way. The links having high connection likelihoods in the communities reveal that links are formed preferentially to create cliques and accordingly promote the clustering level of the communities. The experimental results verify that such a mechanism can be well captured by our approach. CONCLUSIONS/SIGNIFICANCE: Our findings provide a new insight into understanding how links are created in the communities. The computational framework opens a wide range of possibilities to develop new approaches and applications, such as community detection and missing link prediction.

  3. Network Formation Models With Costs for Establishing Links

    NARCIS (Netherlands)

    Slikker, M.; van den Nouweland, C.G.A.M.

    1999-01-01

    In this paper we study endogenous formation of communication networks in situations where the economic possibilities of groups of players can be described by a cooperative game. We concentrate on the in uence that the existence of costs for establishing communication links has on the communication

  4. The fuzziness of Jupiter's core: linking formation and evolution models

    Science.gov (United States)

    Helled, Ravit; Lozovsky, Michael; Vazan, Allona; Stevenson, David; Guillot, Tristan; Hubbard, William

    2017-04-01

    Juno data can be used to better constrain Jupiter's internal structure and origin. First, we present Jupiter's primordial internal structure based on formation models and show that Jupiter's core might not be distinct from the envelope, and that the deep interior can have a gradual heavy-element structure. Second, we explore how such a primordial (non-adiabatic) interior affects Jupiter's long-term evolution. Finally, we will discuss the link between these formation and evolution models and Jupiter's current-state internal structure.

  5. Condensation Mechanism of Hydrocarbon Field Formation.

    Science.gov (United States)

    Batalin, Oleg; Vafina, Nailya

    2017-08-31

    Petroleum geology explains how hydrocarbon fluids are generated, but there is a lack of understanding regarding how oil is expelled from source rocks and migrates to a reservoir. To clarify the process, the multi-layer Urengoy field in Western Siberia was investigated. Based on this example, we have identified an alternative mechanism of hydrocarbon field formation, in which oil and gas accumulations result from the phase separation of an upward hydrocarbon flow. There is evidence that the flow is generated by the gases released by secondary kerogen destruction. This study demonstrates that oil components are carried by the gas flow and that when the flow reaches a low-pressure zone, it condenses into a liquid with real oil properties. The transportation of oil components in the gas flow provides a natural explanation for the unresolved issues of petroleum geology concerning the migration process. The condensation mechanism can be considered as the main process of oil field formation.

  6. Magnetic fields and massive star formation

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Qizhou; Keto, Eric; Ho, Paul T. P.; Ching, Tao-Chung; Chen, How-Huan [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Qiu, Keping [School of Astronomy and Space Science, Nanjing University, 22 Hankou Road, Nanjing 210093 (China); Girart, Josep M.; Juárez, Carmen [Institut de Ciències de l' Espai, (CSIC-IEEC), Campus UAB, Facultat de Ciències, C5p 2, E-08193 Bellaterra, Catalonia (Spain); Liu, Hauyu; Tang, Ya-Wen; Koch, Patrick M.; Rao, Ramprasad; Lai, Shih-Ping [Academia Sinica Institute of Astronomy and Astrophysics, P.O. Box 23-141, Taipei 106, Taiwan (China); Li, Zhi-Yun [Department of Astronomy, University of Virginia, P.O. Box 400325, Charlottesville, VA 22904 (United States); Frau, Pau [Observatorio Astronómico Nacional, Alfonso XII, 3 E-28014 Madrid (Spain); Li, Hua-Bai [Department of Physics, The Chinese University of Hong Kong, Hong Kong (China); Padovani, Marco [Laboratoire de Radioastronomie Millimétrique, UMR 8112 du CNRS, École Normale Supérieure et Observatoire de Paris, 24 rue Lhomond, F-75231 Paris Cedex 05 (France); Bontemps, Sylvain [OASU/LAB-UMR5804, CNRS, Université Bordeaux 1, F-33270 Floirac (France); Csengeri, Timea, E-mail: qzhang@cfa.harvard.edu [Max Planck Institute for Radioastronomy, Auf dem Hügel 69, D-53121 Bonn (Germany)

    2014-09-10

    Massive stars (M > 8 M {sub ☉}) typically form in parsec-scale molecular clumps that collapse and fragment, leading to the birth of a cluster of stellar objects. We investigate the role of magnetic fields in this process through dust polarization at 870 μm obtained with the Submillimeter Array (SMA). The SMA observations reveal polarization at scales of ≲0.1 pc. The polarization pattern in these objects ranges from ordered hour-glass configurations to more chaotic distributions. By comparing the SMA data with the single dish data at parsec scales, we found that magnetic fields at dense core scales are either aligned within 40° of or perpendicular to the parsec-scale magnetic fields. This finding indicates that magnetic fields play an important role during the collapse and fragmentation of massive molecular clumps and the formation of dense cores. We further compare magnetic fields in dense cores with the major axis of molecular outflows. Despite a limited number of outflows, we found that the outflow axis appears to be randomly oriented with respect to the magnetic field in the core. This result suggests that at the scale of accretion disks (≲ 10{sup 3} AU), angular momentum and dynamic interactions possibly due to close binary or multiple systems dominate over magnetic fields. With this unprecedentedly large sample of massive clumps, we argue on a statistical basis that magnetic fields play an important role during the formation of dense cores at spatial scales of 0.01-0.1 pc in the context of massive star and cluster star formation.

  7. Online formative tests linked to microlectures improving academic achievement.

    Science.gov (United States)

    Bouwmeester, Rianne A M; de Kleijn, Renske A M; Freriksen, Astrid W M; van Emst, Maarten G; Veeneklaas, Rob J; van Hoeij, Maggy J W; Spinder, Matty; Ritzen, Magda J; Ten Cate, Olle Th J; van Rijen, Harold V M

    2013-12-01

    Online formative tests (OFTs) are powerful tools to direct student learning behavior, especially when enriched with specific feedback. In the present study, we have investigated the effect of OFTs enriched with hyperlinks to microlectures on examination scores. OFTs, available one week preceding each midterm and the final exams, could be used voluntarily. The use of OFTs was related to scores on midterm and final exams using ANOVA, with prior academic achievement as a covariate. On average, 74% of all students used the online formative tests (OFT+) while preparing for the summative midterm exam. OFT+ students obtained significantly higher grades compared to OFT-students, both without and with correction for previous academic achievement. Two out of three final exam scores did not significantly improve. Students using online formative tests linked to microlectures receive higher grades especially in highly aligned summative tests.

  8. Line formation in microturbulent magnetic fields

    International Nuclear Information System (INIS)

    Domke, H.; Pavlov, G.G.

    1979-01-01

    The formation of Zeeman lines in Gaussian microturbulent magnetic fields is considered assuming LTE. General formulae are derived for the local mean values of the transfer matrix elements. The cases of one-dimensional (longitudinal), isotropic, and two-dimensional (transversal) magnetic microturbulence are studied in some detail. Asymptotic formulae are given for small mean as well as for small microturbulent magnetic fields. Characteristic effects of magnetic microturbulence on the transfer coefficients are: (i) the broadening of the frequency contours, although only for the case of longitudinal Zeeman effect and longitudinal magnetic microturbulence this effect can be described analogous to Doppler broadening, (ii) the appearance of a pseudo-Zeeman structure for nonlongitudinal magnetic microturbulence, (iii) the reduction of maximal values of circular polarization, and (iv) the appearance of characteristic linear polarization effects due to the anisotropy of the magnetic microturbulence. Line contours and polarization of Zeeman triplets are computed for Milne-Eddington atmospheres. It is shown that magnetic intensification due to microturbulent magnetic fields may be much more efficient than that due to regular fields. The gravity center of a Zeeman line observed in circularly polarized light remains a reasonable measure of the line of sight component of the mean magnetic field for a line strength eta 0 < approx. 2. For saturated lines, the gravity center distance depends significantly on the magnetic microturbulence and its anisotropy. The influence of magnetic microturbulence on the ratio of longitudinal field magnetographic signals shows that unique conclusions about the magnetic microstructure can be drawn from the line ratio measurements only in combination with further spectroscopic data or physical reasoning. (orig.)

  9. Linked supramolecular building blocks for enhanced cluster formation

    DEFF Research Database (Denmark)

    McLellan, Ross; Palacios, Maria A.; Beavers, Christine M.

    2015-01-01

    the complex assembly process. The ability to covalently link calix[4]arenes at the methylene bridge provides significantly improved control over the introduction of different metal centres to resulting cluster motifs. Clusters assembled from bis-calix[4]-arenes and transition metal ions or 3d-4 f combinations...

  10. UAV field demonstration of social media enabled tactical data link

    Science.gov (United States)

    Olson, Christopher C.; Xu, Da; Martin, Sean R.; Castelli, Jonathan C.; Newman, Andrew J.

    2015-05-01

    This paper addresses the problem of enabling Command and Control (C2) and data exfiltration functions for missions using small, unmanned, airborne surveillance and reconnaissance platforms. The authors demonstrated the feasibility of using existing commercial wireless networks as the data transmission infrastructure to support Unmanned Aerial Vehicle (UAV) autonomy functions such as transmission of commands, imagery, metadata, and multi-vehicle coordination messages. The authors developed and integrated a C2 Android application for ground users with a common smart phone, a C2 and data exfiltration Android application deployed on-board the UAVs, and a web server with database to disseminate the collected data to distributed users using standard web browsers. The authors performed a mission-relevant field test and demonstration in which operators commanded a UAV from an Android device to search and loiter; and remote users viewed imagery, video, and metadata via web server to identify and track a vehicle on the ground. Social media served as the tactical data link for all command messages, images, videos, and metadata during the field demonstration. Imagery, video, and metadata were transmitted from the UAV to the web server via multiple Twitter, Flickr, Facebook, YouTube, and similar media accounts. The web server reassembled images and video with corresponding metadata for distributed users. The UAV autopilot communicated with the on-board Android device via on-board Bluetooth network.

  11. Strings - Links between conformal field theory, gauge theory and gravity

    International Nuclear Information System (INIS)

    Troost, J.

    2009-05-01

    String theory is a candidate framework for unifying the gauge theories of interacting elementary particles with a quantum theory of gravity. The last years we have made considerable progress in understanding non-perturbative aspects of string theory, and in bringing string theory closer to experiment, via the search for the Standard Model within string theory, but also via phenomenological models inspired by the physics of strings. Despite these advances, many deep problems remain, amongst which a non-perturbative definition of string theory, a better understanding of holography, and the cosmological constant problem. My research has concentrated on various theoretical aspects of quantum theories of gravity, including holography, black holes physics and cosmology. In this Habilitation thesis I have laid bare many more links between conformal field theory, gauge theory and gravity. Most contributions were motivated by string theory, like the analysis of supersymmetry preserving states in compactified gauge theories and their relation to affine algebras, time-dependent aspects of the holographic map between quantum gravity in anti-de-Sitter space and conformal field theories in the bulk, the direct quantization of strings on black hole backgrounds, the embedding of the no-boundary proposal for a wave-function of the universe in string theory, a non-rational Verlinde formula and the construction of non-geometric solutions to supergravity

  12. Field information links permafrost carbon to physical vulnerabilities of thawing

    Science.gov (United States)

    Harden, Jennifer W.; Koven, Charles; Ping, Chien-Lu; Hugelius, Gustaf; McGuire, A. David; Camill, P.; Jorgenson, Torre; Kuhry, Peter; Michaelson, Gary; O'Donnell, Jonathan A.; Schuur, Edward A.G.; Tamocai, Charles; Johnson, K.; Grosse, G.

    2012-01-01

    Deep soil profiles containing permafrost (Gelisols) were characterized for organic carbon (C) and total nitrogen (N) stocks to 3m depths. Using the Community Climate System Model (CCSM4) we calculate cumulative probability functions (PDFs) for active layer depths under current and future climates. The difference in PDFs over time was multiplied by C and N contents of soil horizons in Gelisol suborders to calculate newly thawed C and N, Thawing ranged from 147 PgC with 10 PgN by 2050 (representative concentration pathway RCP scenario 4.5) to 436 PgC with 29 PgN by 2100 (RCP 8.5). Organic horizons that thaw are vulnerable to combustion, and all horizon types are vulnerable to shifts in hydrology and decomposition. The rates and extent of such losses are unknown and can be further constrained by linking field and modelling approaches. These changes have the potential for strong additional loading to our atmosphere, water resources, and ecosystems.

  13. The link between laboratory/field observations and models

    International Nuclear Information System (INIS)

    Cole, C.R.; Foley, M.G.

    1986-01-01

    The various linkages in system performance assessments that integrate disposal program elements must be understood. The linkage between model development and field/laboratory observations is described as the iterative program of site and system characterization for development of an observational-confirmatory data base. This data base is designed to develop, improve, and support conceptual models for site and system behavior. The program consists of data gathering and experiments to demonstrate understanding at various spatial and time scales and degrees of complexity. Understanding and accounting for the decreasing characterization certainty that arises with increasing space and time scales is an important aspect of the link between models and observations. The performance allocation process for setting performance goals and confidence levels, coupled with a performance assessment approach that provides these performance and confidence estimates, will determine when sufficient characterization has been achieved. At each iteration, performance allocation goals are reviewed and revised as necessary. The updated data base and appropriate performance assessment tools and approaches are utilized to identify and design additional tests and data needs necessary to meet current performance allocation goals

  14. Cross-linking reconsidered : binding and cross-linking fields and the cellular response

    NARCIS (Netherlands)

    Sulzer, B.; Boer, R.J. de; Perelson, A.S.

    1996-01-01

    We analyze a model for the reversible cross-linking of cell surface receptors by a collection of bivalent ligands with different affinities for the receptor as would be found in a polyclonal anti-receptor serum. We assume that the amount of cross-linking determines, via a monotonic function, the

  15. Electric field distribution and simulation of avalanche formation due ...

    Indian Academy of Sciences (India)

    Abstract. Electric field distributions and their role in the formation of avalanche due to the passage of heavy ions in parallel grid avalanche type wire chamber detectors are evaluated using a Monte Carlo simulation. The relative merits and demerits of parallel and crossed wire grid configurations are studied. It is found that ...

  16. Electric field distribution and simulation of avalanche formation due ...

    Indian Academy of Sciences (India)

    Electric field distributions and their role in the formation of avalanche due to the passage of heavy ions in parallel grid avalanche type wire chamber detectors are evaluated using a Monte Carlo simulation. The relative merits and demerits of parallel and crossed wire grid configurations are studied. It is found that the crossed ...

  17. Stable sheath formation in expanding magnetic field to divertor plate

    International Nuclear Information System (INIS)

    Tomita, Y.; Takayama, A.; Takamaru, H.; Sato, T.

    2002-01-01

    The stable sheath formation and the effects of charge exchange collisions of ions with cold neutrals for the stable presheath formation in an expanding magnetic field towards a divertor plate is studied by a one-dimensional analysis. The requirement for flow velocity of ions at a plasma-sheath boundary is more restricted than that of the uniform magnetic field, which should be greater than the ion sound speed. The difference, however, between both cases is an order of the Debye length to plasma radius, which is negligibly small. The requirement for ion flow velocity inside a quasi-neutral plasma is investigated by taking into account the effects of the charge exchange collisions. Without neutrals in the quasi-neutral plasma, the ion flow velocity at an injection point should be much greater than the ion sound speed. The unisotropic velocity distribution of injected ions with coupling the expanding magnetic field and the charge exchange collisions might mitigate this requirement. (orig.)

  18. Stable sheath formation in expanding magnetic field to divertor plate

    International Nuclear Information System (INIS)

    Tomita, Y.; Takayama, A.; Takamaru, H.; Sato, T.

    2001-01-01

    The stable sheath formation in expanding magnetic field to a divertor plate was studied theoretically by one-dimensional analysis. In fusion devices the magnetic field is expanding in the direction of the plate, i.e. the magnitude of magnetic field is decreasing to the plate. In this configuration ions are accelerated to the plate due to the gradient of the magnetic field strength, so called a mirror force. The bombardment of accelerated ions to the plate may cause several severe problems to fusion plasmas, for example, release of large amount of impurities from the diverter plate. Limited research efforts have been carried out describing magnetic field effects on various potential formation and particle and heat fluxes to the divertor plate. The plasma-wall interaction in an oblique to the plate but uniform magnetic field has been studied by means of 1D-PIC numerical simulation. This analysis shows the formation of a quasi-neutral magnetic pre-sheath preceding the electrostatic Debye sheath, which scales to the ion gyroradius at the sound speed and to the incidence angle of the magnetic field. Sato clarifies this magnetic pre-sheath is attributed to the ion polarisation drift by the two dimensional kinetic analysis. None of effects, however, of non-uniformity of the magnetic field has been taken into account on the stable electrostatic potential and sheath formation. In this paper, we consider a collisionless sheath model between an infinite metal plate and a quasi-neutral plasma in the expanding magnetic field to the plate. One dimensional kinetic analysis leads that a condition for flow velocity of ions at a plasma-sheath boundary is more restricted than that of the uniform magnetic field, which should be larger than the ion sound speed. The difference, however, between both cases is an order of the Debye length to a plasma radius, which is negligible small. The requirement for the ion flow velocity inside the plasma is obtained from the condition of the quasi

  19. Field guide to Muddy Formation outcrops, Crook County, Wyoming

    Energy Technology Data Exchange (ETDEWEB)

    Rawn-Schatzinger, V.

    1993-11-01

    The objectives of this research program are to (1) determine the reservoir characteristics and production problems of shoreline barrier reservoirs; and (2) develop methods and methodologies to effectively characterize shoreline bamer reservoirs to predict flow patterns of injected and produced fluids. Two reservoirs were selected for detailed reservoir characterization studies -- Bell Creek field, Carter County, Montana that produces from the Lower Cretaceous (Albian-Cenomanian) Muddy Formation, and Patrick Draw field, Sweetwater County, Wyoming that produces from the Upper Cretaceous (Campanian) Almond Formation of the Mesaverde Group. An important component of the research project was to use information from outcrop exposures of the producing formations to study the spatial variations of reservoir properties and the degree to which outcrop information can be used in the construction of reservoir models. This report contains the data and analyses collected from outcrop exposures of the Muddy Formation, located in Crook County, Wyoming, 40 miles south of Bell Creek oil field. The outcrop data set contains permeability, porosity, petrographic, grain size and geologic data from 1-inch-diameter core plugs chilled from the outcrop face, as well as geological descriptions and sedimentological interpretations of the outcrop exposures. The outcrop data set provides information about facies characteristics and geometries and the spatial distribution of permeability and porosity on interwell scales. Appendices within this report include a micropaleontological analyses of selected outcrop samples, an annotated bibliography of papers on the Muddy Formation in the Powder River Basin, and over 950 permeability and porosity values measured from 1-inch-diameter core plugs drilled from the outcrop. All data contained in this resort are available in electronic format upon request. The core plugs drilled from the outcrop are available for measurement.

  20. Investigating the link between imipenem resistance and biofilm formation by Pseudomonas aeruginosa.

    Science.gov (United States)

    Musafer, Hadeel K; Kuchma, Sherry L; Naimie, Amanda A; Schwartzman, Joseph D; Al-Mathkhury, Harith J Fahad; O'Toole, George A

    2014-07-01

    Pseudomonas aeruginosa, a ubiquitous environmental organism, is a difficult-to-treat opportunistic pathogen due to its broad-spectrum antibiotic resistance and its ability to form biofilms. In this study, we investigate the link between resistance to a clinically important antibiotic, imipenem, and biofilm formation. First, we observed that the laboratory strain P. aeruginosa PAO1 carrying a mutation in the oprD gene, which confers resistance to imipenem, showed a modest reduction in biofilm formation. We also observed an inverse relationship between imipenem resistance and biofilm formation for imipenem-resistant strains selected in vitro, as well as for clinical isolates. We identified two clinical isolates of P. aeruginosa from the sputum of cystic fibrosis patients that formed robust biofilms, but were sensitive to imipenem (MIC ≤ 2 μg/ml). To test the hypothesis that there is a general link between imipenem resistance and biofilm formation, we performed transposon mutagenesis of these two clinical strains to identify mutants defective in biofilm formation, and then tested these mutants for imipenem resistance. Analysis of the transposon mutants revealed a role for previously described biofilm factors in these clinical isolates of P. aeruginosa, including mutations in the pilY1, pilX, pilW, algC, and pslI genes, but none of the biofilm-deficient mutants became imipenem resistant (MIC ≥ 8 μg/ml), arguing against a general link between biofilm formation and resistance to imipenem. Thus, assessing biofilm formation capabilities of environmental isolates is unlikely to serve as a good predictor of imipenem resistance. We also discuss our findings in light of the limited literature addressing planktonic antibiotic resistance factors that impact biofilm formation.

  1. Image Formation in Second-Harmonic Near-Field Microscopy

    DEFF Research Database (Denmark)

    Bozhevolnyi, Sergey I.; Lozovski, Valeri Z.; Pedersen, Kjeld

    1999-01-01

    A macroscopic self-consistent approach that enables one to rigorously describe image formation in scanning near-field optical second-harmonic generation microscopy is developed. The self-consistent second-harmonic field is determined by taking into account both the linear and nonlinear...... results calculated for a rectangular object are presented and compared with experimental observations. It is demonstrated that the optical contrast and the spatial resolution are significantly better in the second-harmonic images than in the images obtained at the fundamental frequency....

  2. Polyacetylene: a real material linking condensed matter and field theory

    International Nuclear Information System (INIS)

    Campbell, D.K.

    1981-01-01

    One of the most active subjects of recent research at the interface between field theory and statistical mechanics concerns a real material that seems more properly to belong to the arcana of organic chemistry than to either field theory or statistical methanics. The material is polyacetylene ((CH)/sub x/), a quasi-one dimensional organic polymer with some very interesting and potentially exotic properties. In this discussion, a pedagogical introduction is given to some of the recent theoretical studies of polyacetylene to convey some of the reasons for the intense excitement in this area

  3. Formation of the oil composition of the Yu0 Bazhenov formation, Salym oil field

    Directory of Open Access Journals (Sweden)

    E.V. Soboleva

    2017-05-01

    Full Text Available The Bazhenov horizon of Western Siberia has been studied in considerable detail from different perspectives and different methods, a large number of studies have been devoted to a wide range of issues related to the lithological composition of rocks, their reservoir properties, the study of organic matter, properties and composition of oil at various analytical levels, and many others. This work is devoted to restoring conditions for the formation of oil properties and composition of the Yu0 Salym oil field, based mainly on the geochemical aspects of the study of oil changes both in area and in the section within the productive layer of Salym structure, using some geological data, such as structural plan for the reflecting horizon B (the roof of the Bazhenov formation, having a complex configuration, reservoir temperatures and pressure, well flow rates, and others. There is no single reservoir at the Salym field in the Yu0 formation. For the conclusions of the geological-geochemical interpretation, a sampling of 61 samples of oil from exploration, appraisal and production wells of the initial stages of production was used, since in the future when oil is extracted, the ecology in the deposits changes, and 21 samples of oil from other fields in the West Siberian oil and gas basin. Conventionally, three types of oils are distinguished, differing in their physicochemical parameters, group hydrocarbon and molecular composition. It was suggested that in addition to the own organic matter of the Bazhenov formation, hydrocarbon fluids of the Vasyugan, Tyumen formations and possibly Paleozoic rocks were involved in the formation of the oil composition. The flow of light liquid hydrocarbons and gases occurred along the zones of faults of different genesis and duration of existence.

  4. Non-potential Field Formation in the X-shaped Quadrupole Magnetic Field Configuration

    Energy Technology Data Exchange (ETDEWEB)

    Kawabata, Y.; Shimizu, T. [Department of Earth and Planetary Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Inoue, S., E-mail: kawabata.yusuke@ac.jaxa.jp [Max-Planck-Institute for Solar System Research, Justus-von-Liebig-Weg 3 D-37077 Göttingen (Germany)

    2017-06-20

    Some types of solar flares are observed in X-shaped quadrupolar field configuration. To understand the magnetic energy storage in such a region, we studied non-potential field formation in an X-shaped quadrupolar field region formed in the active region NOAA 11967, which produced three X-shaped M-class flares on 2014 February 2. Nonlinear force-free field modeling was applied to a time series of vector magnetic field maps from the Solar Optical Telescope on board Hinode and the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory . Our analysis of the temporal three-dimensional magnetic field evolution shows that the sufficient free energy had already been stored more than 10 hr before the occurrence of the first M-class flare and that the storage was observed in a localized region. In this localized region, quasi-separatrix layers (QSLs) started to develop gradually from 9 hr before the first M-class flare. One of the flare ribbons that appeared in the first M-class flare was co-spatial with the location of the QSLs, suggesting that the formation of the QSLs is important in the process of energy release. These QSLs do not appear in the potential field calculation, indicating that they were created by the non-potential field. The formation of the QSLs was associated with the transverse photospheric motion of the pre-emerged flux and the emergence of a new flux. This observation indicates that the occurrence of the flares requires the formation of QSLs in the non-potential field in which free magnetic energy is stored in advance.

  5. Linking academic social environments, ego-identity formation, ego virtues, and academic success.

    Science.gov (United States)

    Good, Marie; Adams, Gerald R

    2008-01-01

    This study used Structural Equation Modeling to test an Eriksonian conceptual model linking academic social environments (relationships with faculty and fellow students), ego-identity formation, ego virtues, and academic success. Participants included 765 first-year students at a university in southern Ontario, Canada. Results indicated that supportive relationships with faculty was directly related to higher average grades and perceived academic ability, whereas positive relationships with fellow students was indirectly related to academic success through ego virtues. Positive ego-identity formation (identity achievement) was also indirectly related to academic success through ego virtues.

  6. Network Formation with Endogenous Link Strength and Decreasing Returns to Investment

    Directory of Open Access Journals (Sweden)

    Chiu Ki So

    2016-12-01

    Full Text Available We study the formation of networks where agents choose how much to invest in each relationship. The benefit that an agent can derive from a network depends on the strength of the direct links between agents. We assume that the strength of the direct link between any pair of agents is a concave function of their investments towards each other. In comparison with some existing models of network formation where the strength technology is a convex function of investment, we find that (i the symmetric complete network can dominate the star architecture in terms of total utility; (ii a dominating symmetric complete network needs not be stable; and, (iii star and complete networks can be dominated by small-world networks.

  7. On the influence of applied fields on spinel formation

    International Nuclear Information System (INIS)

    KORTE, C.; FARER, J.K.; RAVISHANKAR, N.; MICHAEL, JOSEPH R.; SCHMALZRIED, J.; CARTER, C.B.

    2000-01-01

    Interfaces play an important role in determining the effect of electric fields on the mechanism of the formation spinel by solid-state reaction. The reaction occurs by the movement of phase boundaries but the rate of this movement can be affected by grain boundaries in the reactants or in the reaction product. Only by understanding these relationships will it be possible to engineer their behavior. As a particular example of such a study, MgIn 2 O 4 can be formed by the reaction between single-crystal MgO substrate and a thin film of In 2 O 3 with or without an applied electric field. High-resolution backscattered electron (BSE) imaging and electron backscattered diffraction (EBSD) in a scanning electron microscope (SEM) has been used to obtain complementary chemical and crystallographic information

  8. On the influence of applied fields on spinel formation

    Energy Technology Data Exchange (ETDEWEB)

    KORTE,C.; FARER,J.K.; RAVISHANKAR,N.; MICHAEL,JOSEPH R.; SCHMALZRIED,J.; CARTER,C.B.

    2000-04-04

    Interfaces play an important role in determining the effect of electric fields on the mechanism of the formation spinel by solid-state reaction. The reaction occurs by the movement of phase boundaries but the rate of this movement can be affected by grain boundaries in the reactants or in the reaction product. Only by understanding these relationships will it be possible to engineer their behavior. As a particular example of such a study, MgIn{sub 2}O{sub 4} can be formed by the reaction between single-crystal MgO substrate and a thin film of In{sub 2}O{sub 3} with or without an applied electric field. High-resolution backscattered electron (BSE) imaging and electron backscattered diffraction (EBSD) in a scanning electron microscope (SEM) has been used to obtain complementary chemical and crystallographic information.

  9. Formation of polycyclic aromatic hydrocarbons from tobacco: the link between low temperature residual solid (char) and PAH formation.

    Science.gov (United States)

    McGrath, Thomas E; Wooten, Jan B; Geoffrey Chan, W; Hajaligol, Mohammad R

    2007-06-01

    The formation of condensed ring polycyclic aromatic hydrocarbons (PAHs) from the pyrolysis of ground tobacco in helium over the temperature range of 350-600 degrees C was investigated. PAH yields in the ng/g range were detected and the maximum yields of all PAHs studied including benzo[a]pyrene (B[a]P) and benzo[a]anthracene (B[a]A) occurred between 500 and 550 degrees C. The pathway to PAH formation in the 350-600 degrees C temperature range is believed to proceed via a carbonization process where the residual solid (char) undergoes a chemical transformation and rearrangement to give a more condensed polycyclic aromatic structure that upon further heating evolves PAH moieties. Extraction of tobacco with water led to a two fold increase in the yields of most PAHs studied. The extraction process removed low temperature non-PAH-forming components, such as alkaloids, organic acids and inorganic salts, and concentrated instead (on a per unit weight basis) tobacco components such as cell wall bio-polymers and lipids. Hexane extraction of the tobacco removed lipophilic components, previously identified as the main source of PAH precursors, but no change in PAH yields was observed from the hexane-extracted tobacco. Tobacco cell wall components such as cellulose, hemicellulose, and lignin are identified as major low temperature PAH precursors. A link between the formation of a low temperature char that evolves PAHs upon heating is established and the observed ng/g yields of PAHs from tobacco highlights a low temperature solid phase formation mechanism that may be operable in a burning cigarette.

  10. Linking topological quantum field theory and nonperturbative quantum gravity

    Science.gov (United States)

    Smolin, Lee

    1995-11-01

    Quantum gravity is studied nonperturbatively in the case in which space has a boundary with finite area. A natural set of boundary conditions is studied in the Euclidean signature theory in which the pullback of the curvature to the boundary is self-dual (with a cosmological constant). A Hilbert space which describes all the information accessible by measuring the metric and connection induced in the boundary is constructed and is found to be the direct sum of the state spaces of all SU(2) Chern-Simon theories defined by all choices of punctures and representations on the spatial boundary S. The integer level k of Chern-Simons theory is found to be given by k=6π/G2Λ+α, where Λ is the cosmological constant and α is a CP breaking phase. Using these results, expectation values of observables which are functions of fields on the boundary may be evaluated in closed form. Given these results, it is natural to make the conjecture that the quantum states of the system are completely determined by measurements made on the boundary. One consequence of this is the Bekenstein bound, which says that once the two metric of the boundary has been measured, the subspace of the physical state space that describes the further information that may be obtained about the interior has finite dimension equal to the exponent of the area of the boundary, in Planck units, times a fixed constant. Finally, these results confirm both the categorical-theoretic ``ladder of dimensions'' picture of Crane and the holographic hypothesis of Susskind and 't Hooft.

  11. Linking Immersive Virtual Field Trips with an Adaptive Learning Platform

    Science.gov (United States)

    Bruce, G.; Taylor, W.; Anbar, A. D.; Semken, S. C.; Buxner, S.; Mead, C.; El-Moujaber, E.; Summons, R. E.; Oliver, C.

    2016-12-01

    The use of virtual environments in science education has been constrained by the difficulty of guiding a learner's actions within the those environments. In this work, we demonstrate how advances in education software technology allow educators to create interactive learning experiences that respond and adapt intelligently to learner input within the virtual environment. This innovative technology provides a far greater capacity for delivering authentic inquiry-driven educational experiences in unique settings from around the world. Our immersive virtual field trips (iVFT) bring students virtually to geologically significant but inaccessible environments, where they learn through authentic practices of scientific inquiry. In one recent example, students explore the fossil beds in Nilpena, South Australia to learn about the Ediacaran fauna. Students interactively engage in 360° recreations of the environment, uncover the nature of the historical ecosystem by identifying fossils with a dichotomous key, explore actual fossil beds in high resolution imagery, and reconstruct what an ecosystem might have looked like millions of years ago in an interactive simulation. With the new capacity to connect actions within the iVFT to an intelligent tutoring system, these learning experiences can be tracked, guided, and tailored individually to the immediate actions of the student. This new capacity also has great potential for learning designers to take a data-driven approach to lesson improvement and for education researchers to study learning in virtual environments. Thus, we expect iVFT will be fertile ground for novel research. Such iVFT are currently in use in several introductory classes offered online at Arizona State University in anthropology, introductory biology, and astrobiology, reaching thousands of students to date. Drawing from these experiences, we are designing a curriculum for historical geology that will be built around iVFT-based exploration of Earth

  12. Study for HDR cross-link for formation flight satellite systems

    Science.gov (United States)

    Nishinaga, Nozomu; Takayama, Yoshihisa; Takahashi, Takashi; Ogawa, Yasuo; Kubooka, Toshihiro; Umehara, Hiroaki

    2003-07-01

    In this paper we studied about optical and millimeter radio wave cross-link for formation flight communication satellite system in a geostationary orbit. In formation flight system, since the distance among the satellites becomes short compared with the conventional inter satellite comunication link, the size and the weight of the communication system can be reduced. If the high data rate cross-link among the satellites which is equal to the whole transponder bandwidth can be established, the functionally distributed communications satellite system can be constructed. Then, by exchanging a part of the satellite system without the physical contact, in other words, by exchange some old satellites and new ones, the fully reconfigurable and long lifetime (from the point of the function) satellite communication system which can follow the paradigm shift in the terrestrial communications technology can be realize. On the other hand, however, since the maximum of relative angle error among two satellites is enlarged, the tracking becomes difficult. In this study, it turns the electric power which is gotten from the shortening the distance to making beam width large. Here, we examine communication among two satellites (10Km distance) where the data rate is 1Gbps.

  13. plink: An R Package for Linking Mixed-Format Tests Using IRT-Based Methods

    Directory of Open Access Journals (Sweden)

    Jonathan P. Weeks

    2010-10-01

    Full Text Available The R package plink has been developed to facilitate the linking of mixed-format tests for multiple groups under a common item design using unidimensional and multidimensional IRT-based methods. This paper presents the capabilities of the package in the context of the unidimensional methods. The package supports nine unidimensional item response models (the Rasch model, 1PL, 2PL, 3PL, graded response model, partial credit and generalized partial credit model, nominal response model, and multiple-choice model and four separate calibration linking methods (mean/sigma, mean/mean, Haebara, and Stocking-Lord. It also includes functions for importing item and/or ability parameters from common IRT software, conducting IRT true-score and observed-score equating, and plotting item response curves and parameter comparison plots.

  14. Petrophysical Study of Szolnok Formation, Endrod Gas Field, Hungary

    Science.gov (United States)

    El Sayed, Abdel Moktader A.; El Sayed, Nahla A.

    2017-12-01

    Investigation of rock porosity and permeability is highly beneficial for geologists, petro-physicist and petroleum engineers in order to evaluate reservoir pore space geometry through the time and space. Clastic reservoir quality and classification could perform based on the petrophysical data correlations. Study of the Szolnok formation was our target. It is composed mainly of sandstones with clay-marlstone and siltstones. Two hundred thirteen-core samples of Upper and Lower Pliocene and Miocene age were subjected for petrophysical investigations. Pore size distribution using MICP, Mercury and Helium porosity, horizontal and vertical permeability were measured for studied core samples. The Szolnok Formation has two main lithologic facies: a. 141 clean sandstone samples and b. 72 siltstone and clay-marlstone samples. Ultrasonic laboratory measurements were carried out for only 30 selected sandstone core samples. Sonic viewer-120 is used to measure sonic velocities and other mechanical properties such as rigidity, bulk modulus and Young’s modulus. Gas permeability and Helium porosity were plotted versus sonic wave velocity indicates that both permeability and porosity could be outlined from either compressional or shear wave velocity. Effective pore radius is outlined from both of them. The highest sample porosity was recorded for the Miocene in age followed by the Lower Pliocene and then for the Upper Pliocene samples respectively. Miocene samples are relatively clayey free followed by Lower Pliocene samples because they have higher sonic velocity (Vp and Vs) than the Upper Pliocene samples. The Miocene and Lower Pliocene samples have relatively lower dynamic mechanical parameters than Upper Pliocene samples which represent good gas reservoirs in the Endrod field. Several regression line equations with high coefficient of correlation have been calculated to predict Szolnok reservoir parameters.

  15. HTP-3 links DSB formation with homolog pairing and crossing over during C. elegans meiosis.

    Science.gov (United States)

    Goodyer, William; Kaitna, Susanne; Couteau, Florence; Ward, Jordan D; Boulton, Simon J; Zetka, Monique

    2008-02-01

    Repair of the programmed meiotic double-strand breaks (DSBs) that initiate recombination must be coordinated with homolog pairing to generate crossovers capable of directing chromosome segregation. Chromosome pairing and synapsis proceed independently of recombination in worms and flies, suggesting a paradoxical lack of coregulation. Here, we find that the meiotic axis component HTP-3 links DSB formation with homolog pairing and synapsis. HTP-3 forms complexes with the DSB repair components MRE-11/RAD-50 and the meiosis-specific axis component HIM-3. Loss of htp-3 or mre-11 recapitulates meiotic phenotypes consistent with a failure to generate DSBs, suggesting that HTP-3 associates with MRE-11/RAD-50 in a complex required for meiotic DSB formation. Loss of HTP-3 eliminates HIM-3 localization to axes and HIM-3-dependent homolog alignment, synapsis, and crossing over. Our study reveals a mechanism for coupling meiotic DSB formation with homolog pairing through the essential participation of an axis component with complexes mediating both processes.

  16. Identification of Plant Extracts that Inhibit the Formation of Diabetes-Linked IAPP Amyloid.

    Science.gov (United States)

    Fuentes, Ana Lucia; Hennessy, Kathleen; Pascual, Jacob; Pepe, Nicole; Wang, In; Santiago, Alexander; Chaggan, Cynthia; Martinez, Jessica; Rivera, Evelyn; Cota, Paola; Cunha, Christina; Nogaj, Luiza A; Moffet, David A

    2016-03-01

    The extracts of 27 vegetables, spices and herbs were screened for their functional ability to inhibit the aggregation of islet amyloid polypeptide (IAPP, amylin) into toxic amyloid aggregates. The aggregation of IAPP has been directly linked to the death of pancreatic β-islet cells in type 2 diabetes. Inhibiting the aggregation of IAPP is believed to have the potential to slow, if not prevent entirely, the progression of this disease. As vegetables, spices and herbs are known to possess many different positive health effects, the extracts of 27 plants (abundant within the United States and spanning several plant families) were screened for their ability to inhibit the formation of toxic IAPP aggregates. Their anti-amyloid activities were assessed through (1) thioflavin T binding assays, (2) visualization of amyloid fibers using atomic force microscopy and (3) cell rescue studies. From this research, mint, peppermint, red bell pepper and thyme emerged as possessing the greatest anti-amyloid activity.

  17. Relaxin of prostatic origin might be linked to perineal hernia formation in dogs.

    Science.gov (United States)

    Niebauer, Gert W; Shibly, Sarina; Seltenhammer, Monika; Pirker, Armin; Brandt, Sabine

    2005-05-01

    Perineal hernia occurs spontaneously in older male dogs after idiopathic weakening of the pelvic diaphragm. Hernias invariably contain cystic paraprostatic tissues. Castration reduces incidence and recurrence after surgical repair. Although cystic prostatic hypertrophy is a consistent feature in patients with perineal hernia, an endocrine link of the disease to steroid sex hormones has not been demonstrated. Employing immunohistochemistry, we found intense relaxin immunoreactivity in dogs with perineal hernia within the epithelia of hypertrophic prostates and in periprostatic tissues. The prostate of normal dogs exhibited similar but less intense relaxin staining. In neutered dogs with prostatic atrophy, relaxin immunostaining was weak or absent. Periprostatic cysts highly expressed relaxin precursors in the fluid phase as shown by SDS-gel electrophoresis. Relaxin of prostatic origin, therefore, is possibly a local factor in connective tissue weakening and subsequently in perineal hernia formation.

  18. A developmental and energetic basis linking larval oyster shell formation to acidification sensitivity

    Science.gov (United States)

    Waldbusser, George G.; Brunner, Elizabeth L.; Haley, Brian A.; Hales, Burke; Langdon, Christopher J.; Prahl, Frederick G.

    2013-05-01

    Acidified waters are impacting commercial oyster production in the U.S. Pacific Northwest, and favorable carbonate chemistry conditions are predicted to become less frequent. Within 48 h of fertilization, unshelled Pacific oyster (Crassostrea gigas) larvae precipitate roughly 90% of their body weight as calcium carbonate. We measured stable carbon isotopes in larval shell and tissue and in algal food and seawater dissolved inorganic carbon in a longitudinal study of larval development and growth. Using these data and measured biochemical composition of larvae, we show that sensitivity of initial shell formation to ocean acidification results from diminished ability to isolate calcifying fluid from surrounding seawater, a limited energy budget and a strong kinetic demand for calcium carbonate precipitation. Our results highlight an important link between organism physiology and mineral kinetics in larval bivalves and suggest the consideration of mineral kinetics may improve understanding winners and losers in a high CO2 world.

  19. Preparation of qualified specialists for the field of it from D-Link

    Directory of Open Access Journals (Sweden)

    Pavel V. Romasevich

    2017-12-01

    Full Text Available The article is devoted to the consideration of D-Link's experience in the development and implementation of educational programs for the training of qualified specialists for the field of IT. To remain competitive, a specialist needs to be constantly trained, especially in such a rapidly changing field as IT. The training programs developed by D-Link for IT professionals help to gain knowledge about new technologies and their application in industrial conditions. You can confirm the high level of professionalism by getting the D-Link certificate. To obtain a certificate, you must pass one or two certification exams, depending on the chosen training course. Training of specialists engaged in the development, implementation and support of solutions based on D-Link solutions, in addition to the company's specialists, is carried out by authorized training centers and academic partners of D-Link. On the D-Link’s distance learning and certification portal, distance learning courses are available for studying. The article focuses on various forms of cooperation between D-Link and higher education institutions: the development of original teaching materials, the organization of distance learning and its integration into the learning process, the creation of laboratories to support practical classes and research activities, the management of course and diploma work, the organization of industrial practice.

  20. Hydroxyhomocitrulline Is a Collagen-Specific Carbamylation Mark that Affects Cross-link Formation.

    Science.gov (United States)

    Taga, Yuki; Tanaka, Keisuke; Hamada, Chieko; Kusubata, Masashi; Ogawa-Goto, Kiyoko; Hattori, Shunji

    2017-10-19

    Carbamylation is a non-enzymatic post-translational modification that physiologically occurs during aging and is a risk factor for various diseases. The most common product of carbamylation is homocitrulline (HCit), where a lysine (Lys) amino group has reacted with urea-derived cyanate. HCit has recently been detected in collagen; however, given that 15%-90% of total Lys in collagen is hydroxylated, it is unclear how hydroxylation affects collagen carbamylation. Here, we identified a collagen-specific carbamylation product, hydroxyhomocitrulline (HHCit), and showed that high levels of HHCit are correlated with age in rat tissue collagen and in vivo carbamylation in mice, as well as with the decline of kidney function in the serum of dialysis patients. Proteomic analysis of the carbamylated collagens identified α2(I) Lys 933 , a major cross-linking site, as a preferential HHCit site. Furthermore, our results suggest that hydroxylysine carbamylation affects the mechanical properties of connective tissue by competitively inhibiting collagen cross-link formation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Linking Deep-Waer Prey Fields with Odontocete Population Structure and Behavior

    Science.gov (United States)

    2015-09-30

    1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Linking deep -water prey fields with odontocete population...column to examine the coherence between surface and deep -water prey characteristics • Examine the relationship between historical beaked whale...ground- truthed with net tows. Beaked whale habitat use was quantified using a combination of synoptic visual observations from the ship and

  2. Klf15 deficiency is a molecular link between heart failure and aortic aneurysm formation.

    Science.gov (United States)

    Haldar, Saptarsi M; Lu, Yuan; Jeyaraj, Darwin; Kawanami, Daiji; Cui, Yingjie; Eapen, Sam J; Hao, Caili; Li, Yan; Doughman, Yong-Qiu; Watanabe, Michiko; Shimizu, Koichi; Kuivaniemi, Helena; Sadoshima, Junichi; Margulies, Kenneth B; Cappola, Thomas P; Jain, Mukesh K

    2010-04-07

    Current therapies for diseases of heart muscle (cardiomyopathy) and aorta (aortopathy) include inhibitors of the renin-angiotensin system, beta-adrenergic antagonists, and the statin class of cholesterol-lowering agents. These therapies have limited efficacy, as adverse cardiovascular events continue to occur with some frequency in patients taking these drugs. Although cardiomyopathy and aortopathy can coexist in a number of conditions (for example, Marfan's syndrome, acromegaly, pregnancy, and aging), pathogenetic molecular links between the two diseases remain poorly understood. We reasoned that identification of common molecular perturbations in these two tissues could point to therapies for both conditions. Here, we show that deficiency of the transcriptional regulator Kruppel-like factor 15 (Klf15) in mice leads to both heart failure and aortic aneurysm formation through a shared molecular mechanism. Klf15 concentrations are markedly reduced in failing human hearts and in human aortic aneurysm tissues. Mice deficient in Klf15 develop heart failure and aortic aneurysms in a p53-dependent and p300 acetyltransferase-dependent fashion. KLF15 activation inhibits p300-mediated acetylation of p53. Conversely, Klf15 deficiency leads to hyperacetylation of p53 in the heart and aorta, a finding that is recapitulated in human tissues. Finally, Klf15-deficient mice are rescued by p53 deletion or p300 inhibition. These findings highlight a molecular perturbation common to the pathobiology of heart failure and aortic aneurysm formation and suggest that manipulation of KLF15 function may be a productive approach to treat these morbid diseases.

  3. Linking lowermost mantle structure, core-mantle boundary heat flux and mantle plume formation

    Science.gov (United States)

    Li, Mingming; Zhong, Shijie; Olson, Peter

    2018-04-01

    The dynamics of Earth's lowermost mantle exert significant control on the formation of mantle plumes and the core-mantle boundary (CMB) heat flux. However, it is not clear if and how the variation of CMB heat flux and mantle plume activity are related. Here, we perform geodynamic model experiments that show how temporal variations in CMB heat flux and pulses of mantle plumes are related to morphologic changes of the thermochemical piles of large-scale compositional heterogeneities in Earth's lowermost mantle, represented by the large low shear velocity provinces (LLSVPs). We find good correlation between the morphologic changes of the thermochemical piles and the time variation of CMB heat flux. The morphology of the thermochemical piles is significantly altered during the initiation and ascent of strong mantle plumes, and the changes in pile morphology cause variations in the local and the total CMB heat flux. Our modeling results indicate that plume-induced episodic variations of CMB heat flux link geomagnetic superchrons to pulses of surface volcanism, although the relative timing of these two phenomena remains problematic. We also find that the density distribution in thermochemical piles is heterogeneous, and that the piles are denser on average than the surrounding mantle when both thermal and chemical effects are included.

  4. Petrophysical study of Szolnok Formation, Endrod gas field,

    Directory of Open Access Journals (Sweden)

    Abdel Moktader A. El Sayed

    2017-03-01

    Full Text Available Results of both porosity and permeability can be used by geologists, petrophysicists, and petroleum engineers to evaluate reservoir rock, heterogeneity, and pore space history through the time of deposition and lithifaction. On the other hand, reservoir quality as well as reservoir classification could be performed based on these data correlation. The Szolnok Formation is composed mainly of turbidity elastic deposits while siltstones are intercalated by sandstone beds and streaks of marls. In the present study, 213 core samples are obtained from the Szolnok Formation of the Great Hungarian plain, Hungary. Both horizontal and vertical permeability are measured. The Szolnok Formation has two main lithologic groups: 1. clean sandstone (141 samples and 2. siltstone – marl (72 samples, it can easily differentiate between good, intermediate or even bad reservoirs. Acoustic laboratory measurements have been carried out for only 30 sandstone rock samples parallel to the bedding plane (horizontal. This paper aims to evaluate some petrophysical relationships. On the other hand, both Wyllie and Raymer models were applied for porosity estimation from seismic velocity. It is worthy to mention that reservoir diagnosis of the Szolnok Formation was our target as well. Both the porosity and permeability variation range characterizing the detected lithologic facies of the Szolnok Formation are useful for reservoir zonation. The relationship between helium and mercury porosity for whole studied samples and sandstone samples as well, are supported by a high correlation coefficient and allow its application for prediction of porosity while it reduces costs and time of laboratory measurements. The evaluation of different calculated equations for porosity from compressional wave velocity data of the Szolnok Formation are studied and the relationship between velocity and porosity displays a clear inverse trend. The comparison between laboratory porosity and sonic

  5. POLARIZED LINE FORMATION IN NON-MONOTONIC VELOCITY FIELDS

    Energy Technology Data Exchange (ETDEWEB)

    Sampoorna, M.; Nagendra, K. N., E-mail: sampoorna@iiap.res.in, E-mail: knn@iiap.res.in [Indian Institute of Astrophysics, Koramangala, Bengaluru 560034 (India)

    2016-12-10

    For a correct interpretation of the observed spectro-polarimetric data from astrophysical objects such as the Sun, it is necessary to solve the polarized line transfer problems taking into account a realistic temperature structure, the dynamical state of the atmosphere, a realistic scattering mechanism (namely, the partial frequency redistribution—PRD), and the magnetic fields. In a recent paper, we studied the effects of monotonic vertical velocity fields on linearly polarized line profiles formed in isothermal atmospheres with and without magnetic fields. However, in general the velocity fields that prevail in dynamical atmospheres of astrophysical objects are non-monotonic. Stellar atmospheres with shocks, multi-component supernova atmospheres, and various kinds of wave motions in solar and stellar atmospheres are examples of non-monotonic velocity fields. Here we present studies on the effect of non-relativistic non-monotonic vertical velocity fields on the linearly polarized line profiles formed in semi-empirical atmospheres. We consider a two-level atom model and PRD scattering mechanism. We solve the polarized transfer equation in the comoving frame (CMF) of the fluid using a polarized accelerated lambda iteration method that has been appropriately modified for the problem at hand. We present numerical tests to validate the CMF method and also discuss the accuracy and numerical instabilities associated with it.

  6. Triggered star formation: Rotation, magnetic fields and outflows

    Science.gov (United States)

    Frank, A.; Li, S.; Blackman, E. G.

    2015-12-01

    Star formation can be triggered by compression from wind or supernova driven shock waves that sweep over molecular clouds. In a previous work we used Adaptive Mesh Refinement (AMR) simulation methods, including sink particles, to simulate the full collapse of a stable Bonnor-Ebert sphere subjected to a passing shock. We tracked the flow of cloud material after a star (a sink particle) had formed. For rotating clouds we observed the formation of disks which then interact with the post-shock flow. In this paper we take the next step forward in complexity, presenting first results of simulations that include a magnetized cloud. Our results show that after a disk is formed a collimated magneto-centrifugal outflow is launched. The outflow is bipolar but asymmetric, due to interactions with the shocked flow. We explore the influence of the outflows on the post-triggering collapse dynamics.

  7. Formation of Field-reversed-Configuration Plasma with Punctuated-betatron-orbit Electrons

    International Nuclear Information System (INIS)

    Welch, D.R.; Cohen, S.A.; Genoni, T.C.; Glasser, A.H.

    2010-01-01

    We describe ab initio, self-consistent, 3D, fully electromagnetic numerical simulations of current drive and field-reversed-configuration plasma formation by odd-parity rotating magnetic fields (RMFo). Magnetic-separatrix formation and field reversal are attained from an initial mirror configuration. A population of punctuated-betatron-orbit electrons, generated by the RMFo, carries the majority of the field-normal azimuthal electrical current responsible for field reversal. Appreciable current and plasma pressure exist outside the magnetic separatrix whose shape is modulated by the RMFo phase. The predicted plasma density and electron energy distribution compare favorably with RMFo experiments.

  8. Modulation Formats for Beyond-100Gbps Ethernet Optical Links – A Review of Research

    DEFF Research Database (Denmark)

    Jensen, Jesper Bevensee; Iglesias Olmedo, Miguel; Tafur Monroy, Idelfonso

    2013-01-01

    The current increase in data-centers traffic and cloud-based services presents a formidable challenge for optical interconnects. We examine these challenges, and review recent breakthroughs in advanced modulation formats formats for intensity modulation - direct detection....

  9. Distinct steps of cross-linking, self-association, and maturation of tropoelastin are necessary for elastic fiber formation.

    Science.gov (United States)

    Sato, Fumiaki; Wachi, Hiroshi; Ishida, Marie; Nonaka, Risa; Onoue, Satoshi; Urban, Zsolt; Starcher, Barry C; Seyama, Yoshiyuki

    2007-06-08

    Elastic fibers play an important role in the characteristic resilience of many tissues. The assembly of tropoelastin into a fibrillar matrix is a complex stepwise process and the deposition and cross-linking of tropoelastin are believed to be key steps of elastic fiber formation. However, the detailed mechanisms of elastic fiber assembly have not been defined yet. Here, we demonstrate the relationship between deposition and the cross-linking/maturation of tropoelastin. Our data show that a C-terminal half-fragment of tropoelastin encoded by exons 16-36 (BH) is deposited onto microfibrils, yet we detect very limited amounts of the cross-linking amino acid, desmosine, an indicator of maturation, whereas the N-terminal half-fragment encoded by exons 2-15 (FH) was deficient for both deposition and cross-linking, suggesting that elastic fiber formation requires full-length tropoelastin molecules. A series of experiments using mutant BH fragments, lacking either exon 16 or 30, or a deletion of both exons showed that self-association of tropoelastin polypeptides was an early step in elastic fiber assembly. Immunofluorescence and Western blot assay showed that the treatment of cell culture medium or conditioned medium with beta-aminopropionitrile to inhibit cross-linking, prevented both the deposition and polymerization of tropoelastin. In conclusion, our present results support the view that self-association and oxidation by lysyl oxidase precedes tropoelastin deposition onto microfibrils and the entire molecule of tropoelastin is required for this following maturation process.

  10. Electric Field Structures in Thin Films: Formation and Properties

    DEFF Research Database (Denmark)

    Cassidy, Andrew; Plekan, Oksana; Balog, Richard

    2014-01-01

    by combining layers of different spontelectric materials. This is demonstrated using the spontelectric materials nitrous oxide, toluene, isoprene, isopentane, and CF2Cl2. These yield a variety of tailored electric field structures, with individual layers harboring fields between 107 and 108 V/m. Fields may......A newly discovered class of molecular materials, so-called “spontelectrics”, display spontaneous electric fields. Here we show that the novel properties of spontelectrics can be used to create composite spontelectrics, illustrating how electric fields in solid films may be structured on the nanoscale...

  11. Formation of v-shaped potentials. [auroral zone electric fields

    Science.gov (United States)

    Thiemann, H.; Singh, N.; Schunk, R. W.

    1983-01-01

    The V-shaped potential structures formed by the injection of a non-neutral electron current into a cold background plasma were simulated numerically. The injection disturbs the initial quasi-neutral plasma, leading to the excitation of strong turbulences which heat the plasma. This leads to expulsion of the plasma from the simulation region. Due to ambipolar electric fields the current injection is interrupted and the initial background plasma is extracted from the system. A particle composition with the characteristics of the two plasma reservoirs now represents the plasma in the simulation region. The interaction of the electron beam with this plasma excites turbulences of smaller amplitudes. A nearly constant time averaged potential drop with nonstationary distribution develops across the system. Single and multiple double layers may form for the duration of one ion plasma period.

  12. Importance of field-reversing ion ring formation in hot electron plasma

    Energy Technology Data Exchange (ETDEWEB)

    Ikuta, K.

    1975-11-01

    Formation of the field reversing ion ring in the mirror confined hot electron plasma may offer a device to confine the fusion plasma even under the restriction of the present technology. (Author) (GRA)

  13. Nimbus-7 Narrow Field of View (NFOV) Maximum Likelihood Cloud Estimation (MLCE) Data in Native Format

    Data.gov (United States)

    National Aeronautics and Space Administration — NIMBUS7_NFOV_MLCE data are Nimbus 7 Narrow Field of View (NFOV) Maximum Likelihood Cloud Estimation (MLCE) Data in Native Format.The NIMBUS7_NFOV_MLCE data set uses...

  14. Linking Publications to Instruments, Field Campaigns, Sites and Working Groups: The ARM Experience

    Science.gov (United States)

    Troyan, D.; Cialella, A. T.; Gregory, L.; Lazar, K.; Liang, M.; Ma, L.; Tilp, A.; Wagener, R.

    2017-12-01

    For the past 25 years, the ARM Climate Research Facility - a US Department of Energy scientific user facility - has been collecting atmospheric data in different climatic regimes using both in situ and remote instrumentation. Configuration of the facility's components has been designed to improve the understanding and representation, in climate and earth system models, of clouds and aerosols. Placing a premium on long-term continuous data collection resulted in terabytes of data having been collected, stored, and made accessible to any interested person. All data is accessible via the ARM.gov website and the ARM Data Discovery Tool. A team of metadata professionals assign appropriate tags to help facilitate searching the databases for desired data. The knowledge organization tools and concepts are used to create connections between data, instruments, field campaigns, sites, and measurements are familiar to informatics professionals. Ontology, taxonomy, classification, and thesauri are among the customized concepts put into practice for ARM's purposes. In addition to the multitude of data available, there have been approximately 3,000 journal articles that utilize ARM data. These have been linked to specific ARM web pages. Searches of the complete ARM publication database can be done using a separate interface. This presentation describes how ARM data is linked to instruments, sites, field campaigns, and publications through the application of standard knowledge organization tools and concepts.

  15. Effect of an External Electric Field on Positronium Formation in Positron Spur

    DEFF Research Database (Denmark)

    Mogensen, O. E.

    1975-01-01

    The decrease of positronium (Ps) formation in condensed matter caused by the presence of an external electric field is discussed in terms of the spur reaction model of Ps formation. The rather few experimental results available are shown to be in good agreement with the predictions of the model...

  16. Computer simulations of channel meandering and the formation of point bars: Linking channel dynamics to the preserved stratigraphy

    Science.gov (United States)

    Sun, T.; Covault, J. A.; Pyrcz, M.; Sullivan, M.

    2012-12-01

    Meandering rivers are probably one of the most recognizable geomorphic features on earth. As they meander across alluvial and delta plains, channels migrate laterally and develop point bars, splays, levees and other geomorphic and sedimentary features that compose substantial portions of the fill within many sedimentary basins. These basins can include hydrocarbon producing fields. Therefore, a good understanding of the processes of meandering channels and their associated deposits is critical for exploiting these reservoirs in the subsurface. In the past couple of decades, significant progress has been made in our understanding of the morphodynamics of channel meandering. Basic fluid dynamics and sediment transport (Ikeda and Parker, 1981; Howard, 1992) has shown that many characteristic features of meandering rivers, such as the meandering wavelength, growth rate and downstream migration rate, can be predicted quantitatively. As a result, a number of variations and improvement of the theory have emerged (e.g., Blondeaux and Seminara, 1985; Parker and Andrews, 1985, 1986; and Sun et al., 2001a, b).The main improvements include the recognition of so called "bar-bend" interactions, where the development of bars on the channel bed and their interactions with the channel bend is recognized as a primary cause for meandering channels to develop greater complexity than the classic goose-neck meander bend shapes, such as compound bend. Recently, Sun and others have shown that the spatial patterns of width variations in meandering channels can be explained by an extrinsic periodic flow variations coupled with the intrinsic bend instability dynamics. In contrast to the significant improvement of our understanding of channel meandering, little work has been done to link the geomorphic features of meandering channels to the geometry and heterogeneity of the deposits they form and ultimately preserves. A computer simulation model based on the work of Sun and others (1996, 2001

  17. Link 'soil-plant' as critical in formation committed doses from uptake of long-lived radionuclides

    International Nuclear Information System (INIS)

    Kravetz, A. P.; Pavlenko, Y. A.; Grodzinsky, D. M.

    1994-01-01

    General algorithm of calculation dose from intake 137 Cs and 90 Sr depending upon level of pollution and agrochemical type of soil where trophycal chains to begin with, have been proposed. This methods consider link 'soil → plant' as critical in formation of doses from the intake long-lived radionuclides. Calculation of committed dose as function of type of soil and level of radionuclide pollution have been realized for seven main soil types of the White Russian and Ukrainian Wooded district. (author)

  18. Linking Delinquency and Personal Identity Formation across Adolescence: Examining Between- and Within-Person Associations

    Science.gov (United States)

    Mercer, Natalie; Crocetti, Elisabetta; Branje, Susan; van Lier, Pol; Meeus, Wim

    2017-01-01

    Adolescent delinquency and identity formation have both been described in relation to the confusion, doubt, and need for individuation and autonomy faced by adolescents. While theoretical conceptualizations (e.g., Erikson, 1968; Moffitt, 1993) suggest that delinquency and identity formation might be developmentally intertwined across adolescence,…

  19. Role of special cross-links in structure formation of bacterial DNA polymer

    Science.gov (United States)

    Agarwal, Tejal; Manjunath, G. P.; Habib, Farhat; Lakshmi Vaddavalli, Pavana; Chatterji, Apratim

    2018-01-01

    Using data from contact maps of the DNA-polymer of Escherichia coli (E. Coli) (at kilobase pair resolution) as an input to our model, we introduce cross-links between monomers in a bead-spring model of a ring polymer at very specific points along the chain. Via suitable Monte Carlo simulations, we show that the presence of these cross-links leads to a particular organization of the chain at large (micron) length scales of the DNA. We also investigate the structure of a ring polymer with an equal number of cross-links at random positions along the chain. We find that though the polymer does get organized at the large length scales, the nature of the organization is quite different from the organization observed with cross-links at specific biologically determined positions. We used the contact map of E. Coli bacteria which has around 4.6 million base pairs in a single circular chromosome. In our coarse-grained flexible ring polymer model, we used 4642 monomer beads and observed that around 80 cross-links are enough to induce the large-scale organization of the molecule accounting for statistical fluctuations caused by thermal energy. The length of a DNA chain even of a simple bacterial cell such as E. Coli is much longer than typical proteins, hence we avoided methods used to tackle protein folding problems. We define new suitable quantities to identify the large scale structure of a polymer chain with a few cross-links.

  20. Effect of angular momentum alignment and strong magnetic fields on the formation of protostellar discs

    Science.gov (United States)

    Gray, William J.; McKee, Christopher F.; Klein, Richard I.

    2018-01-01

    Star-forming molecular clouds are observed to be both highly magnetized and turbulent. Consequently, the formation of protostellar discs is largely dependent on the complex interaction between gravity, magnetic fields, and turbulence. Studies of non-turbulent protostellar disc formation with realistic magnetic fields have shown that these fields are efficient in removing angular momentum from the forming discs, preventing their formation. However, once turbulence is included, discs can form in even highly magnetized clouds, although the precise mechanism remains uncertain. Here, we present several high-resolution simulations of turbulent, realistically magnetized, high-mass molecular clouds with both aligned and random turbulence to study the role that turbulence, misalignment, and magnetic fields have on the formation of protostellar discs. We find that when the turbulence is artificially aligned so that the angular momentum is parallel to the initial uniform field, no rotationally supported discs are formed, regardless of the initial turbulent energy. We conclude that turbulence and the associated misalignment between the angular momentum and the magnetic field are crucial in the formation of protostellar discs in the presence of realistic magnetic fields.

  1. High-Frequency Promoter Firing Links THO Complex Function to Heavy Chromatin Formation

    DEFF Research Database (Denmark)

    Mouaikel, John; Causse, Sébastien Z; Rougemaille, Mathieu

    2013-01-01

    The THO complex is involved in transcription, genome stability, and messenger ribonucleoprotein (mRNP) formation, but its precise molecular function remains enigmatic. Under heat shock conditions, THO mutants accumulate large protein-DNA complexes that alter the chromatin density of target genes......-molecule fluorescence insitu hybridization measurements show that heavy chromatin formation correlates with an unusually high firing pace of the promoter with more than 20 transcription events per minute. Heavy chromatin formation closely follows the modulation of promoter firing and strongly correlates with polymerase...

  2. Band Formation in Mixtures of Oppositely Charged Colloids Driven by an ac Electric Field

    NARCIS (Netherlands)

    Vissers, T.; van Blaaderen, A.; Imhof, A.

    2011-01-01

    We present experiments on pattern formation in a Brownian system of oppositely charged colloids driven by an ac electric field. Using confocal laser scanning microscopy we observe complete segregation of the two particle species into bands perpendicular to a field of sufficient strength when the

  3. Beneficial biofilms in marine aquaculture? Linking points of biofilm formation mechanisms in Pseudomonas aeruginosa and Pseudoalteromonas species

    Directory of Open Access Journals (Sweden)

    Wiebke Wesseling

    2015-07-01

    Full Text Available For marine aquaculture it is suggested that a specific substrate coated with a beneficial biofilm could prevent fish egg clutches from pathogenic infestations and improve the water quality and health of adult fish while, at the same time, minimising the need for the application of antibiotics. In marine biotopes, the habitat of Pseudoalteromonas species (a strain with suggested beneficial properties, biofilms are mostly discussed in the context of fouling processes. Hence research focuses on unravelling the mechanisms of biofilm formation aiming to prevent formation or to destroy existing biofilms. Initially in this review, particular components of biofilm formation in Pseudomonas aeruginosa, a gram-negative model organism that is responsible for nosocomial infections and considered as a food spoiling agent, are described (extracellular appendages, role of matrix components, cell-cell signalling to get an advanced understanding of biofilm formation. The aim of this treatise is to seek linking points for biofilm formation of P. aeruginosa and Pseudoalteromonas sp., respectively. Furthermore, approaches are discussed for how biofilm formation can be realized to improve fish (larvae rearing by species of the genus Pseudoalteromonas.

  4. Magnetic fields and star formation: evidence from imaging polarimetry of the Serpens Reflection Nebula

    Energy Technology Data Exchange (ETDEWEB)

    Warren-Smith, R.F.; Draper, P.W.; Scarrott, S.M.

    1987-08-01

    CCD imaging of the Serpens bipolar reflection nebula shows it to be surrounded by dark material having spiral density structure. Multi-colour polarization mapping also reveals details of the surrounding magnetic field, indicating that this also has spiral structure. These observations are discussed along with current ideas about the role of magnetic fields during star formation. An interpretation involving the non-axisymmetric magnetically braked collapse of a protostellar cloud is proposed and a resulting magnetic field configuration is described which can account for the observations. Evidence is also discussed for the formation of a binary star system within the nebula, resulting from the fragmentation of a magnetized protostellar disc.

  5. Kinetic limitation in the formation of end-linked elastomer networks

    Czech Academy of Sciences Publication Activity Database

    Meissner, Bohumil; Matějka, Libor

    2005-01-01

    Roč. 46, č. 24 (2005), s. 10618-10625 ISSN 0032-3861 R&D Projects: GA ČR GA203/05/2252 Keywords : end-linked elastomer networks * effect of stoichiometry * kinetic limitations Subject RIV: CD - Macromolecular Chemistry Impact factor: 2.849, year: 2005

  6. Multibody motion in implicitly constrained director format with links via explicit constraints

    DEFF Research Database (Denmark)

    Nielsen, Martin Bjerre; Krenk, Steen

    2013-01-01

    with the presence of kinematic joints for linking bodies together. The equations of motion are derived from Hamilton’s equations with an augmented Hamiltonian in which internal and external constraints initially are included via Lagrange multipliers. Subsequently the Lagrange multipliers associated with internal...

  7. Gully formation on Mars: Two recent phases of formation suggested by links between morphology, slope orientation and insolation history

    Science.gov (United States)

    Morgan, Gareth A.; Head, James W.; Forget, François; Madeleine, Jean-Baptiste; Spiga, Aymeric

    2010-08-01

    The unusual 80 km diameter Noachian-aged Asimov crater in Noachis Terra (46°S, 5°E) is characterized by extensive Noachian-Hesperian crater fill and a younger superposed annulus of valleys encircling the margins of the crater floor. These valleys provide an opportunity to study the relationships of gully geomorphology as a function of changing slope orientation relative to solar insolation. We found that the level of development of gullies was highly correlated with slope orientation and solar insolation. The largest and most complex gully systems, with the most well-developed fluvial landforms, are restricted to pole-facing slopes. In contrast, gullies on equator-facing slopes are smaller, more poorly developed and integrated, more highly degraded, and contain more impact craters. We used a 1D version of the Laboratoire de Météorologie Dynamique GCM, and slope geometries (orientation and angle), driven by predicted spin-axis/orbital parameter history, to assess the distribution and history of surface temperatures in these valleys during recent geological history. Surface temperatures on pole-facing slopes preferential for water ice accumulation and subsequent melting are predicted to occur as recently as 0.5-2.1 Ma, which is consistent with age estimates of gully activity elsewhere on Mars. In contrast, the 1D model predicts that water ice cannot accumulate on equator-facing slopes until obliquities exceed 45°, suggesting they are unlikely to have been active over the last 5 Ma. The correlation of the temperature predictions and the geological evidence for age differences suggests that there were two phases of gully formation in the last few million years: an older phase in which top-down melting occurred on equator-facing slopes and a younger more robust phase on pole-facing slopes. The similarities of small-scale fluvial erosion features seen in the gullies on Mars and those observed in gullies cut by seasonal and perennial snowmelt in the Antarctic Dry

  8. Molecular Mechanisms Underlying the Link between Nuclear Receptor Function and Cholesterol Gallstone Formation

    Directory of Open Access Journals (Sweden)

    Mary Carmen Vázquez

    2012-01-01

    Full Text Available Cholesterol gallstone disease is highly prevalent in western countries, particularly in women and some specific ethnic groups. The formation of water-insoluble cholesterol crystals is due to a misbalance between the three major lipids present in the bile: cholesterol, bile salts, and phospholipids. Many proteins implicated in biliary lipid secretion in the liver are regulated by several transcription factors, including nuclear receptors LXR and FXR. Human and murine genetic, physiological, pathophysiological, and pharmacological evidence is consistent with the relevance of these nuclear receptors in gallstone formation. In addition, there is emerging data that also suggests a role for estrogen receptor ESR1 in abnormal cholesterol metabolism leading to gallstone disease. A better comprehension of the role of nuclear receptor function in gallstone formation may help to design new and more effective therapeutic strategies for this highly prevalent disease condition.

  9. Formation of turbulent structures and the link to fluctuation driven sheared flows

    DEFF Research Database (Denmark)

    Windisch, T; Grulke, O; Naulin, Volker

    2011-01-01

    The formation of turbulent structures in weakly developed drift-wave turbulence is investigated using experimental data obtained in a linear laboratory device. The findings are compared with fully non-linear numerical simulation results. The formation of structures occurs in a region, in which...... the divergence of the Reynolds stress, which is one term in the momentum balance, has a maximum. The generation of a time-averaged shear layer is not observed, but for transient events the shearing rate can become sufficiently strong to decorrelate the fluctuations. This happens when the energy flow...

  10. Fate of Tetrabromobisphenol A (TBBPA) and Formation of Ester- and Ether-Linked Bound Residues in an Oxic Sandy Soil.

    Science.gov (United States)

    Li, Fangjie; Wang, Jiajia; Jiang, Bingqi; Yang, Xue; Nastold, Peter; Kolvenbach, Boris; Wang, Lianhong; Ma, Yini; Corvini, Philippe François-Xavier; Ji, Rong

    2015-11-03

    Bound-residue formation is a major dissipation process of most organic xenobiotics in soil. However, both the formation and nature of bound residues of tetrabromobisphenol A (TBBPA) in soil are unclear. Using a 14C-tracer, we studied the fate of TBBPA in an oxic soil during 143 days of incubation. TBBPA dissipated with a half-life of 14.7 days; at the end of incubation, 19.6% mineralized and 66.5% formed bound residues. Eight extractable metabolites were detected, including TBBPA methyl ethers, single-ring bromophenols, and their methyl ethers. Bound residues (mostly bound to humin) rapidly formed during the first 35 days. The amount of those humin-bound residues then quickly decreased, whereas total bound residues decreased slowly. By contrast, residues bound to humic acids and fulvic acids increased continuously until a plateau was reached. Ester- and ether-linked residues accounted for 9.6-27.0% of total bound residues during the incubation, with ester linkages being predominant. Residues bound via ester linkages consisted of TBBPA, TBBPA monomethyl ether, and an unknown polar compound. Our results indicated that bound-residue formation is the major pathway of TBBPA dissipation in oxic soil and provide first insights into the chemical structure of the reversibly ester-linked bound residues of TBBPA and its metabolites.

  11. A structural and kinetic link between membrane association and amyloid fibril formation of α-Synuclein

    OpenAIRE

    Heise, Henrike; Etzkorn, Manuel; Hoyer, Wolfgang; Buell, Alexander; Strodel, Birgit; Willbold, Dieter; Shaykhalishahi, Hamed; Poojari, Chetan; Uluca, Boran; Wördehoff, Michael; Viennet, Thibault

    2017-01-01

    The protein α-Synuclein (αS) is linked to Parkinson's disease through its abnormal aggregation, which is thought to involve an interplay between cytosolic and membrane-bound forms of αS. Therefore, better insights into the molecular determinants of membrane association and their implications for protein aggregation may help deciphering the pathogenesis of Parkinson's disease. Following previous studies using micelles and vesicles, we present a comprehensive study of αS interaction with phosph...

  12. Linking a Learning Progression for Natural Selection to Teachers' Enactment of Formative Assessment

    Science.gov (United States)

    Furtak, Erin Marie

    2012-01-01

    Learning progressions, or representations of how student ideas develop in a domain, hold promise as tools to support teachers' formative assessment practices. The ideas represented in a learning progression might help teachers to identify and make inferences about evidence collected of student thinking, necessary precursors to modifying…

  13. Parents' Marital Distress, Divorce, and Remarriage: Links with Daughters' Early Family Formation Transitions

    Science.gov (United States)

    Amato, Paul R.; Kane, Jennifer B.

    2011-01-01

    The authors used data from the Add Health study to estimate the effects of parents' marital status and relationship distress on daughters' early family formation transitions. Outcomes included traditional transitions (marriage and marital births) and nontraditional transitions (cohabitation and nonmarital births). Relationship distress among…

  14. Plasma-gun-assisted field-reversed configuration formation in a conical θ-pinch

    Energy Technology Data Exchange (ETDEWEB)

    Weber, T. E., E-mail: tweber@lanl.gov; Intrator, T. P. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Smith, R. J. [Department of Aeronautics and Astronautics, University of Washington, Seattle, Washington 98195 (United States)

    2015-04-15

    Injection of plasma via an annular array of coaxial plasma guns during the pre-ionization phase of field-reversed configuration (FRC) formation is shown to catalyze the bulk ionization of a neutral gas prefill in the presence of a strong axial magnetic field and change the character of outward flux flow during field-reversal from a convective process to a much slower resistive diffusion process. This approach has been found to significantly improve FRC formation in a conical θ-pinch, resulting in a ∼350% increase in trapped flux at typical operating conditions, an expansion of accessible formation parameter space to lower densities and higher temperatures, and a reduction or elimination of several deleterious effects associated with the pre-ionization phase.

  15. Plasma-gun-assisted field-reversed configuration formation in a conical θ-pinch

    Science.gov (United States)

    Weber, T. E.; Intrator, T. P.; Smith, R. J.

    2015-04-01

    Injection of plasma via an annular array of coaxial plasma guns during the pre-ionization phase of field-reversed configuration (FRC) formation is shown to catalyze the bulk ionization of a neutral gas prefill in the presence of a strong axial magnetic field and change the character of outward flux flow during field-reversal from a convective process to a much slower resistive diffusion process. This approach has been found to significantly improve FRC formation in a conical θ-pinch, resulting in a ˜350% increase in trapped flux at typical operating conditions, an expansion of accessible formation parameter space to lower densities and higher temperatures, and a reduction or elimination of several deleterious effects associated with the pre-ionization phase.

  16. Mechanical and hydrological characterization of the near-field surrounding excavations in a geologic salt formation

    Energy Technology Data Exchange (ETDEWEB)

    Howard, Clifford L. [Sandia National Laboratories, Albuquerque, NM (United States)

    2014-09-01

    The technical basis for salt disposal of nuclear waste resides in salt’s favorable physical, mechanical and hydrological characteristics. Undisturbed salt formations are impermeable. Upon mining, the salt formation experiences damage in the near-field rock proximal to the mined opening and salt permeability increases dramatically. The volume of rock that has been altered by such damage is called the disturbed rock zone (DRZ).

  17. Direct observation of electric field induced pattern formation and particle aggregation in ferrofluids

    Energy Technology Data Exchange (ETDEWEB)

    Rajnak, Michal; Kopcansky, Peter; Timko, Milan [Institute of Experimental Physics SAS, Watsonova 47, 04001 Košice (Slovakia); Petrenko, Viktor I. [Joint Institute for Nuclear Research, Joliot-Curie 6, 141980 Dubna, Moscow Region (Russian Federation); Kyiv Taras Shevchenko National University, Volodymyrska Street 64, Kyiv 01033 (Ukraine); Avdeev, Mikhail V. [Joint Institute for Nuclear Research, Joliot-Curie 6, 141980 Dubna, Moscow Region (Russian Federation); Ivankov, Olexandr I. [Joint Institute for Nuclear Research, Joliot-Curie 6, 141980 Dubna, Moscow Region (Russian Federation); Kyiv Taras Shevchenko National University, Volodymyrska Street 64, Kyiv 01033 (Ukraine); Moscow Institute of Physics and Technology, Institutskiy per. 9, Dolgoprudniy 141700 (Russian Federation); Feoktystov, Artem [Jülich Centre for Neutron Science (JCNS) at Heinz Maier-Leibnitz Zentrum (MLZ), Forschungszentrum Jülich GmbH, Lichtenbergstr. 1, 85747 Garching (Germany); Dolnik, Bystrik; Kurimsky, Juraj [Faculty of Electrical Engineering and Informatics, Technical University of Košice, Letná 9, 04200 Košice (Slovakia)

    2015-08-17

    Ferrofluids typically respond to magnetic fields and can be manipulated by external magnetic fields. Here, we report on formation of visually observable patterns in a diluted low-polarity ferrofluid exposed to external electric fields. This presents a specific type of ferrofluid structure driven by a combined effect of electrohydrodynamics and electrical body forces. The free charge and permittivity variation are considered to play a key role in the observed phenomenon. The corresponding changes in the ferrofluid structure have been found at nanoscale as well. By small-angle neutron scattering (SANS), we show that the magnetic nanoparticles aggregate in direct current (dc) electric field with a strong dependence on the field intensity. The anisotropic aggregates preferably orient in the direction of the applied electric field. Conducting SANS experiments with alternating current (ac) electric fields of various frequencies, we found a critical frequency triggering the aggregation process. Our experimental study could open future applications of ferrofluids based on insulating liquids.

  18. Direct observation of electric field induced pattern formation and particle aggregation in ferrofluids

    Science.gov (United States)

    Rajnak, Michal; Petrenko, Viktor I.; Avdeev, Mikhail V.; Ivankov, Olexandr I.; Feoktystov, Artem; Dolnik, Bystrik; Kurimsky, Juraj; Kopcansky, Peter; Timko, Milan

    2015-08-01

    Ferrofluids typically respond to magnetic fields and can be manipulated by external magnetic fields. Here, we report on formation of visually observable patterns in a diluted low-polarity ferrofluid exposed to external electric fields. This presents a specific type of ferrofluid structure driven by a combined effect of electrohydrodynamics and electrical body forces. The free charge and permittivity variation are considered to play a key role in the observed phenomenon. The corresponding changes in the ferrofluid structure have been found at nanoscale as well. By small-angle neutron scattering (SANS), we show that the magnetic nanoparticles aggregate in direct current (dc) electric field with a strong dependence on the field intensity. The anisotropic aggregates preferably orient in the direction of the applied electric field. Conducting SANS experiments with alternating current (ac) electric fields of various frequencies, we found a critical frequency triggering the aggregation process. Our experimental study could open future applications of ferrofluids based on insulating liquids.

  19. Effect of a Transverse Magnetic Field on Stray Grain Formation of Ni-Based Single Crystal Superalloy During Directional Solidification

    Science.gov (United States)

    Xuan, Weidong; Liu, Huan; Lan, Jian; Li, Chuanjun; Zhong, Yunbo; Li, Xi; Cao, Guanghui; Ren, Zhongming

    2016-12-01

    The effect of a transverse magnetic field on stray grain formation during directional solidification of superalloy was investigated. Experimental results indicated that the transverse magnetic field effectively suppressed the stray grain formation on the side the primary dendrite diverges from the mold wall. Moreover, the quenched experimental results indicated that the solid/liquid interface shape was obviously changed in a transverse magnetic field. The effect of a transverse magnetic field on stray grain formation was discussed.

  20. Formation and locking of the ``slinky mode'' in reversed-field pinches

    Science.gov (United States)

    Fitzpatrick, Richard

    1999-04-01

    The formation and breakup of the "slinky mode" in a Reversed-Field Pinch (RFP) is investigated analytically. The slinky mode is a toroidally localized, coherent interference pattern in the magnetic field, which corotates with the plasma at the reversal surface. This mode forms, via a series of bifurcations, as a result of the nonlinear coupling of multiple m=1 core tearing modes. The slinky mode breaks up via a second series of bifurcations. However, the typical mode amplitude below which slinky breakup is triggered is much smaller than that above which slinky formation occurs. Analytic expressions for the slinky formation and breakup thresholds are obtained in all regimes of physical interest. The locking of the slinky mode to a static error field is also investigated analytically. Either the error field arrests the rotation of the plasma at the reversal surface before the formation of the slinky mode, so that the mode subsequently forms as a nonrotating mode, or the slinky mode forms as a rotating mode and subsequently locks to the error field. Analytic expressions for the locking and unlocking thresholds are obtained in all regimes of physical interest.

  1. Triplet energies and excimer formation in meta- and para-linked carbazolebiphenyl matrix materials.

    Science.gov (United States)

    Bagnich, Sergey A; Rudnick, Alexander; Schroegel, Pamela; Strohriegl, Peter; Köhler, Anna

    2015-06-28

    We present a spectroscopic investigation on the effect of changing the position where carbazole is attached to biphenyl in carbazolebiphenyl (CBP) on the triplet state energies and the propensity to excimer formation. For this, two CBP derivatives have been prepared with the carbazole moieties attached at the (para) 4- and 4(')-positions (pCBP) and at the (meta) 3- and 3(')-positions (mCBP) of the biphenyls. These compounds are compared to analogous mCDBP and pCDBP, i.e. two highly twisted carbazoledimethylbiphenyls, which have a high triplet energy at about 3.0 eV and tend to form triplet excimers in a neat film. This torsion in the structure is associated with localization of the excited state onto the carbazole moieties. We find that in mCBP and pCBP, excimer formation is prevented by localization of the triplet excited state onto the central moiety. As conjugation can continue from the central biphenyls into the nitrogen of the carbazole in the para-connected pCBP, emission involves mainly the benzidine. By contrast, the meta-linkage in mCBP limits conjugation to the central biphenyl. The associated shorter conjugation length is the reason for the higher triplet energy of 2.8 eV in mCBP compared with the 2.65 eV in pCBP. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  2. Peculiarities of stress field formation during cutting isotropic material by mining machine cutters

    Science.gov (United States)

    Gabov, V. V.; Zadkov, D. A.

    2017-10-01

    Peculiarities of the cutting process of isotropic material by mining machine cutters are considered. The objective of the studies is revealing regularities of the process of stress field formation in the pre-cutter zone of the breakable massif and assessment of the possibility of purposeful control of cutting process parameters. Taking into account the multifactorial nature and randomness of the process of elementary chippage formation, an experimental method of studies with the use of full-sized cutters was accepted as a determining principle. A stand for cutting an isotropic transparent material with an optical method of observing stress fields in the under-cutter zone, the procedure of conducting studies and results were presented in the paper. The use of quasi-isotropic acryl glass as an object for destruction allowed reducing the influence of multifactorial nature and randomness on the process of formation of the stress field and elementary chippage. The modes, excluding continuous chip formation, determined by, on the one hand, the phenomenon of material creep – at low cutting speeds, and, on the other hand – cutting speed modes by the terms of thermal conditions, were determined. Continuation of experimental studies of the cutting process of quasi-isotropic materials is aimed at revealing the most significant factors and determination of their influence on the change of phase parameters of elementary chippage and at revealing the very opportunity of formation of elementary chippage characteristics.

  3. Barium-cross-linked alginate-gelatine microcapsule as a potential platform for stem cell production and modular tissue formation.

    Science.gov (United States)

    Alizadeh Sardroud, Hamed; Nemati, Sorour; Baradar Khoshfetrat, Ali; Nabavinia, Mahbobeh; Beygi Khosrowshahi, Younes

    2017-08-01

    Influence of gelatine concentration and cross-linker ions of Ca 2+ and Ba 2+ was evaluated on characteristics of alginate hydrogels and proliferation behaviours of model adherent and suspendable stem cells of fibroblast and U937 embedded in alginate microcapsules. Increasing gelatine concentration to 2.5% increased extent of swelling to 15% and 25% for barium- and calcium-cross-linked hydrogels, respectively. Mechanical properties also decreased with increasing swelling of hydrogels. Both by increasing gelatine concentration and using barium ions increased considerably the proliferation of encapsulated model stem cells. Barium-cross-linked alginate-gelatine microcapsule tested for bone building block showed a 13.5 ± 1.5-fold expansion for osteoblast cells after 21 days with deposition of bone matrix. The haematopoietic stem cells cultured in the microcapsule after 7 days also showed up to 2-fold increase without adding any growth factor. The study demonstrates that barium-cross-linked alginate-gelatine microcapsule has potential for use as a simple and efficient 3D platform for stem cell production and modular tissue formation.

  4. Formation and locking of the ``slinky mode'' in reversed field pinches

    Science.gov (United States)

    Fitzpatrick, Richard

    1998-11-01

    The formation and breakup of the ``slinky mode'' in an RFP is investigated using analytic techniques previously employed to examine mode locking phenomena in tokamaks. The slinky mode is a toroidally localized, coherent interference pattern in the magnetic field which co-rotates with the plasma at the reversal surface. This mode forms, as a result of the nonlinear coupling of multiple m=1 core tearing modes, via a bifurcation which is similar to that by which toroidally coupled tearing modes lock together in a tokamak. The slinky mode breaks up via a second bifurcation which is similar to that by which toroidally coupled tearing modes in a tokamak unlock. However, the typical m=1 mode amplitude below which slinky breakup is triggered is much smaller than that above which slinky formation occurs. Analytic expressions for the slinky formation and breakup thresholds are obtained in all regimes of physical interest. The locking of the slinky mode to a static error-field is also investigated analytically. Either the error-field arrests the rotation of the plasma at the reversal surface before the formation of the slinky mode, so that the mode subsequently forms as a non-rotating mode, or the slinky mode forms as a rotating mode and subsequently locks to the error-field. Analytic expressions for the locking and unlocking thresholds are obtained in all regimes of physical interest. The problems associated with a locked slinky mode can be alleviated by canceling out the accidentally produced error-field responsible for locking the slinky mode, using a deliberately created ``control'' error-field. Alternatively, the locking angle of the slinky mode can be swept toroidally by rotating the control field.

  5. Notch-dependent epithelial fold determines boundary formation between developmental fields in the Drosophila antenna.

    Science.gov (United States)

    Ku, Hui-Yu; Sun, Y Henry

    2017-07-01

    Compartment boundary formation plays an important role in development by separating adjacent developmental fields. Drosophila imaginal discs have proven valuable for studying the mechanisms of boundary formation. We studied the boundary separating the proximal A1 segment and the distal segments, defined respectively by Lim1 and Dll expression in the eye-antenna disc. Sharp segregation of the Lim1 and Dll expression domains precedes activation of Notch at the Dll/Lim1 interface. By repressing bantam miRNA and elevating the actin regulator Enable, Notch signaling then induces actomyosin-dependent apical constriction and epithelial fold. Disruption of Notch signaling or the actomyosin network reduces apical constriction and epithelial fold, so that Dll and Lim1 cells become intermingled. Our results demonstrate a new mechanism of boundary formation by actomyosin-dependent tissue folding, which provides a physical barrier to prevent mixing of cells from adjacent developmental fields.

  6. Linking field observations, Landsat and MODIS data to estimate agricultural change in European Russia.

    Science.gov (United States)

    de Beurs, K. M.; Ioffe, G.

    2011-12-01

    Agricultural reform has been one of the most important anthropogenic change processes in European Russia that has been unfolding since the formal collapse of the Soviet Union at the end of 1991. Widespread land abandonment is perhaps the most vivid side effect of the reform, even visible in synoptic imagery. Currently, Russia is transitioning into a country with an internal "archipelago" of islands of productive agriculture around cities embedded in a matrix of unproductive, abandoned lands. This heterogeneous spatial pattern is mainly driven by depopulation of the least favorable parts of the countryside, where "least favorable" is a function of fertility, remoteness, and their interaction. In this work we provide a satellite, GIS and field based overview of the current agricultural developments in Russia and look beyond the unstable period immediately following the collapse of the Soviet Union. We apply Landsat images in one of Russia's oblasts to create a detailed land cover map. We then use a logistic model to link the Landsat land cover map with the inter-annual variability in key phenological parameters calculated from MODIS to derive the percent of cropland per 500m MODIS pixel. By evaluating the phenological characteristics of the MODIS curves for each year we determine whether a pixel was actually cropped or left fallow. A comparison of satellite-estimated cropped areas with regional statistics (by rayon) revealed that the satellite estimates are highly correlated with the regional statistics for both arable lands and successfully cropped areas. We use the crop maps to determine the number of times a particular area was cropped between 2002 and 2009 by summing all the years with crops per pixel. This variable provides a good indication about the intensification and de-intensification of the Russian croplands over the last decade. We have visited several rural areas in Russia and we link the satellite data with information acquired through field interviews

  7. MicroRNAs Control Macrophage Formation and Activation: The Inflammatory Link between Obesity and Cardiovascular Diseases

    Directory of Open Access Journals (Sweden)

    Richard Cheng-An Chang

    2014-07-01

    Full Text Available Activation and recruitment of resident macrophages in tissues in response to physiological stress are crucial regulatory processes in promoting the development of obesity-associated metabolic disorders and cardiovascular diseases. Recent studies have provided compelling evidence that microRNAs play important roles in modulating monocyte formation, macrophage maturation, infiltration into tissues and activation. Macrophage-dependent systemic physiological and tissue-specific responses also involve cell-cell interactions between macrophages and host tissue niche cell components, including other tissue-resident immune cell lineages, adipocytes, vascular smooth muscle and others. In this review, we highlight the roles of microRNAs in regulating the development and function of macrophages in the context of obesity, which could provide insights into the pathogenesis of obesity-related metabolic syndrome and cardiovascular diseases.

  8. FRC formation studies in a field reversed theta pinch with a variable length coil

    International Nuclear Information System (INIS)

    Maqueda, R.; Sobehart, J.; Rodrigo, A.B.

    1987-01-01

    The formation phase of field reversed configurations (FRC) produced using a theta pinch has received considerable attention lately in connection with the possibility of developing formation methods in time scales longer than the Alven radial time, which would permit the use of low-voltage technology and represent an important engineering simplification in the trend towards larger scale machines sup (1)). The mechanisms leading to the loss of trapped reversed flux during the preheating 2 ) and formation sup (3,4)) stages, looking for maximization of this quantity in order to improve on the stability and transport properties of the configuration in its final equilibrium state are investigated. As a result, semi-emperical scaling laws have been obtained relating the reversed flux loss with experimental operating parameters during the early stages of the formation process 1 ). (author) [pt

  9. Geochemical evaluation of Pabdeh Formation in Nosrat field, southeast Persian Gulf using Rock- Eval VI pyrolysis

    Directory of Open Access Journals (Sweden)

    mohammad sadeghi

    2015-02-01

    Full Text Available The present study was performed on 59 drillhole cuttings from Pabdeh Formation in Nosrat oil field using Rock- Eval VI pryrolysis. Geochemical analysis indicated that Pabdeh Formation possesses poor to good hydrocarbon potential. Plotting S1 against TOC suggests that samples were not affected by polluting substances such as crude oil and lubricants while drilling operation. Jones organic fancies diagram shows B-BC area indicating that Pabdeh Formation was deposited in marine anoxic to oxic environments. HI vesus Tmax shows that most samples initially have had type II kerogen and now reflecting a mixture of type II to III kerogen (capable of generating oil that have already entered oil generation window. In addition, S1+S2 versus TOC plot also suggests that Pabdeh Formation can be considered as a capable hydrocarbon generating source rock in the study area.

  10. Linking lipid architecture to bilayer structure and mechanics using self-consistent field modelling.

    Science.gov (United States)

    Pera, H; Kleijn, J M; Leermakers, F A M

    2014-02-14

    To understand how lipid architecture determines the lipid bilayer structure and its mechanics, we implement a molecularly detailed model that uses the self-consistent field theory. This numerical model accurately predicts parameters such as Helfrichs mean and Gaussian bending modulus kc and k̄ and the preferred monolayer curvature J(0)(m), and also delivers structural membrane properties like the core thickness, and head group position and orientation. We studied how these mechanical parameters vary with system variations, such as lipid tail length, membrane composition, and those parameters that control the lipid tail and head group solvent quality. For the membrane composition, negatively charged phosphatidylglycerol (PG) or zwitterionic, phosphatidylcholine (PC), and -ethanolamine (PE) lipids were used. In line with experimental findings, we find that the values of kc and the area compression modulus kA are always positive. They respond similarly to parameters that affect the core thickness, but differently to parameters that affect the head group properties. We found that the trends for k̄ and J(0)(m) can be rationalised by the concept of Israelachivili's surfactant packing parameter, and that both k̄ and J(0)(m) change sign with relevant parameter changes. Although typically k̄ 0, especially at low ionic strengths. We anticipate that these changes lead to unstable membranes as these become vulnerable to pore formation or disintegration into lipid disks.

  11. Linking lipid architecture to bilayer structure and mechanics using self-consistent field modelling

    International Nuclear Information System (INIS)

    Pera, H.; Kleijn, J. M.; Leermakers, F. A. M.

    2014-01-01

    To understand how lipid architecture determines the lipid bilayer structure and its mechanics, we implement a molecularly detailed model that uses the self-consistent field theory. This numerical model accurately predicts parameters such as Helfrichs mean and Gaussian bending modulus k c and k ¯ and the preferred monolayer curvature J 0 m , and also delivers structural membrane properties like the core thickness, and head group position and orientation. We studied how these mechanical parameters vary with system variations, such as lipid tail length, membrane composition, and those parameters that control the lipid tail and head group solvent quality. For the membrane composition, negatively charged phosphatidylglycerol (PG) or zwitterionic, phosphatidylcholine (PC), and -ethanolamine (PE) lipids were used. In line with experimental findings, we find that the values of k c and the area compression modulus k A are always positive. They respond similarly to parameters that affect the core thickness, but differently to parameters that affect the head group properties. We found that the trends for k ¯ and J 0 m can be rationalised by the concept of Israelachivili's surfactant packing parameter, and that both k ¯ and J 0 m change sign with relevant parameter changes. Although typically k ¯ 0 m ≫0, especially at low ionic strengths. We anticipate that these changes lead to unstable membranes as these become vulnerable to pore formation or disintegration into lipid disks

  12. Linking varve-formation processes to climate and lake conditions at Tiefer See (NE Germany)

    Science.gov (United States)

    Dräger, Nadine; Kienel, Ulrike; Plessen, Birgit; Ott, Florian; Brademann, Brian; Pinkerneil, Sylvia; Brauer, Achim

    2017-04-01

    Annually laminated (varved) lake sediments represent unique archives in continental areas providing both, precise chronologies and seasonally resolving proxy data. Monitoring of physical, chemical and biological processes influencing lake sediment formation are a suitable approach for detailed proxy understanding of varved sediment records. Lake Tiefer See (NE Germany) indicates deposition of varved sediments today as well as millennia ago (Dräger et al., 2016; Kienel et al., 2013). Therefore, the lake provides the possibility to trace current seasonal layer formation in the lake and to pair these data to climate and lake conditions (Kienel et al., 2016). Lake Tiefer See was formed during the last glaciation and is part of the Klocksin Lake Chain, a subglacial channel system that crosses the Pomeranian terminal moraine. The lake is a mesotrophic hard water lake with a maximum depth of 63 m and a surface area of 0.75 km2. During four consecutive years (2012-2015) the particulate matter deposition was trapped at bi-weekly to monthly resolution at three different water depths (5, 12 and 50 m). The sediment trap material was analysed for sediment flux and organic matter and calcite content. In addition, we monitored limnological parameters (e.g. temperature, pH, conductivity, oxygen content) as well as the meteorological conditions (e.g. temperature, wind speed and direction, precipitation) with a monitoring and climate station installed on the lake. These data describe strength and duration of lake mixing and lake stagnation phases. Our results show distinct seasonal peaks in sediment formation, which correspond to the spring and summer productivity phases comprising of diatom blooms and calcite precipitation. This observation is in line with microfacies results from surface sediment cores. The content of biogenic calcite content decreases in the trapped material with increasing water depth indicating dissolution processes. However, the strength of calcite

  13. Characterization of compact-toroid injection during formation, translation, and field penetration

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, T., E-mail: cstd14003@g.nihon-u.ac.jp; Sekiguchi, J.; Asai, T. [Nihon University, Chiyoda-ku, Tokyo 101-8308 (Japan); Roche, T.; Allfrey, I.; Gota, H.; Cordero, M.; Garate, E.; Kinley, J.; Valentine, T.; Waggoner, W.; Binderbauer, M. [Tri Alpha Energy, Inc., P.O. Box 7010, Rancho Santa Margarita, California 92688 (United States); Tajima, T. [Tri Alpha Energy, Inc., P.O. Box 7010, Rancho Santa Margarita, California 92688 (United States); Department of Physics and Astronomy, University of California, Irvine, California 92697 (United States)

    2016-11-15

    We have developed a compact toroid (CT) injector system for particle refueling of the advanced beam-driven C-2U field-reversed configuration (FRC) plasma. The CT injector is a magnetized coaxial plasma gun (MCPG), and the produced CT must cross the perpendicular magnetic field surrounding the FRC for the refueling of C-2U. To simulate this environment, an experimental test stand has been constructed. A transverse magnetic field of ∼1 kG is established, which is comparable to the C-2U axial magnetic field in the confinement section, and CTs are fired across it. On the test stand we have been characterizing and studying CT formation, ejection/translation from the MCPG, and penetration into transverse magnetic fields.

  14. Characterization of compact-toroid injection during formation, translation, and field penetration

    Science.gov (United States)

    Matsumoto, T.; Roche, T.; Allfrey, I.; Sekiguchi, J.; Asai, T.; Gota, H.; Cordero, M.; Garate, E.; Kinley, J.; Valentine, T.; Waggoner, W.; Binderbauer, M.; Tajima, T.

    2016-11-01

    We have developed a compact toroid (CT) injector system for particle refueling of the advanced beam-driven C-2U field-reversed configuration (FRC) plasma. The CT injector is a magnetized coaxial plasma gun (MCPG), and the produced CT must cross the perpendicular magnetic field surrounding the FRC for the refueling of C-2U. To simulate this environment, an experimental test stand has been constructed. A transverse magnetic field of ˜1 kG is established, which is comparable to the C-2U axial magnetic field in the confinement section, and CTs are fired across it. On the test stand we have been characterizing and studying CT formation, ejection/translation from the MCPG, and penetration into transverse magnetic fields.

  15. THE LINK BETWEEN RARE-EARTH PEAK FORMATION AND THE ASTROPHYSICAL SITE OF THE R PROCESS

    Energy Technology Data Exchange (ETDEWEB)

    Mumpower, Matthew R. [Theory Division, Los Alamos National Laboratory, Los Alamos, NM 87544 (United States); McLaughlin, Gail C. [Department of Physics, North Carolina State University, Raleigh, NC 27695 (United States); Surman, Rebecca [Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States); Steiner, Andrew W., E-mail: matthew@mumpower.net [Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996 (United States)

    2016-12-20

    The primary astrophysical source of the rare-earth elements is the rapid neutron capture process ( r process). The rare-earth peak that is seen in the solar r -process residuals has been proposed to originate as a pile-up of nuclei during the end of the r process. We introduce a new method utilizing Monte Carlo studies of nuclear masses in the rare-earth region, that includes self-consistently adjusting β -decay rates and neutron capture rates, to find the mass surfaces necessary for the formation of the rare-earth peak. We demonstrate our method with two types of astrophysical scenario, one corresponding to conditions typical of hot winds from core-collapse supernovae and stellar-mass accretion disks, and one corresponding to conditions typical of the ejection of the material from the tidal tails of neutron star mergers. In each type of astrophysical condition, this method successfully locates a region of enhanced stability in the mass surface that is responsible for the rare-earth peak. For each scenario, we find that the change in the mass surface has qualitatively different features, thus future measurements can shed light on the type of environment in which the r process occurred.

  16. Trickle-down boundary conditions in aeolian dune-field pattern formation

    Science.gov (United States)

    Ewing, R. C.; Kocurek, G.

    2015-12-01

    One the one hand, wind-blown dune-field patterns emerge within the overarching boundary conditions of climate, tectonics and eustasy implying the presence of these signals in the aeolian geomorphic and stratigraphic record. On the other hand, dune-field patterns are a poster-child of self-organization, in which autogenic processes give rise to patterned landscapes despite remarkable differences in the geologic setting (i.e., Earth, Mars and Titan). How important are climate, tectonics and eustasy in aeolian dune field pattern formation? Here we develop the hypothesis that, in terms of pattern development, dune fields evolve largely independent of the direct influence of 'system-scale' boundary conditions, such as climate, tectonics and eustasy. Rather, these boundary conditions set the stage for smaller-scale, faster-evolving 'event-scale' boundary conditions. This 'trickle-down' effect, in which system-scale boundary conditions indirectly influence the event scale boundary conditions provides the uniqueness and richness of dune-field patterned landscapes. The trickle-down effect means that the architecture of the stratigraphic record of dune-field pattern formation archives boundary conditions, which are spatially and temporally removed from the overarching geologic setting. In contrast, the presence of an aeolian stratigraphic record itself, reflects changes in system-scale boundary conditions that drive accumulation and preservation of aeolian strata.

  17. Field captures of wild melon fly (Diptera: Tephritidae) with an improved male attractant, raspberry ketone formate.

    Science.gov (United States)

    Jang, Eric B; Casana-Giner, Victor; Oliver, James E

    2007-08-01

    Field-trapping evaluations of the new male attractant, formic acid 4-(3-oxobutyl) phenyl ester (raspberry ketone formate [RKF]) were conducted in Hawaii with wild populations of melon flies, Bactrocera cucurbitae Coquillett (Diptera: Tephritidae), to determine its activity in the field and to evaluate new plastic matrix formulations. All tests were compared with the standard melon fly attractant 4-(4-acetoxyphenyl) -2-butanone (cuelure [CL]), which is the attractant of choice for detection programs aimed at melon fly and other cuelure-responding Bactrocera fruit flies. Results of these tests over a range of doses on cotton wicks showed that at a 1-g dose raspberry ketone formate was 1.5-2 times more attractive compared with cuelure for up to 11 wk in the field. Lower doses applied on cotton wicks were less active, presumably due to hydrolysis of RKF to raspberry ketone. Raspberry ketone formate embedded in a plastic plug formulation also was field tested, and it was shown to be more attractive to male melon fly compared with cuelure. The use of this new attractant in control and detection programs is discussed.

  18. Nonlinearities tolerant modulation format enabled Tb/s superchannel transmission over 420 km of unrepeated Raman amplified link

    Science.gov (United States)

    Bilal, Syed Muhammad; Goroshko, Kseniia; Louchet, Hadrien; Koltchanov, Igor; Richter, André

    2017-07-01

    the same transmission distance and capacity. So for practical realization the nonlinearity robust modulation format PM-QPSK using SRO has been identified as the most promising approach for superchannel implementation of unrepeated Raman amplified links.

  19. Building The Bigger Picture - Using a field study geology programme to link and contextualise classroom topics.

    Science.gov (United States)

    Allen, Lesley

    2013-04-01

    Cornwall, UK, has been designated a World Heritage Site for industrial heritage, based on the extensive mining history built around hydrothermal deposits of tin and copper suite deposits. These deposits are found in a very varied and complex geological setting. The tectonic activity which emplaced the deposits also produced intense folding and faulting of Carboniferous and Devonian marine sediments, major and minor igneous intrusions, regional and contact metamorphism, and the emplacement of an ophiolite sequence on the Lizard peninsula. The region is targeted by college and university geology student groups from across the UK. It is also the home of the world famous Camborne School of Mines, part of the University of Exeter. We have developed a comprehensive series of field visits to cover all these geological aspects. We also use the history of mining as a context within which to teach the social, environmental and economic aspects of the geology curriculum at A Level. By this means we can reveal how disparate geological topics link together through 3 physical dimensions plus time. Field visits motivate students; they enthuse and excite them and help them to understand the large-scale and 3D visualisation aspects of geology, the timescales involved, and also assist students in developing observational and practical field and mapping skills. The series of visits also helps to bring many aspects of the curriculum together into a more complete picture. Site 1 - Bude. Intense folding of marine sediments with tectonic and sedimentary structures in cyclical sands and shales and some turbidites. Competent and incompetent rocks, axial planar cleavage, etc. Site 2 - Praa Sands. Minor porphyritic intrusion with baked & chilled margins and flow aligned feldspars. (Also incidental raised beach due to post-glacial isostatic rebound.) Site 3 - Rinsey Cove. Contact zone where 'roof' of major granitic intrusion intrudes slates. Pegmatites, classic marginal features, xenoliths

  20. Dissociating conscious expectancies from automatic link formation in associative learning: a review on the so-called Perruchet effect.

    Science.gov (United States)

    Perruchet, Pierre

    2015-04-01

    A long-running debate in the literature on conditioning in humans focuses on the question of whether conditioned responses are the product of automatic link formation processes governed by the standard laws of simple associative learning, or the consequence of participants' inferences about the relationships between the 2 related events, E1 and E2, which would lead E1 to generate a conscious expectancy of E2. A paradigm aimed at dissociating the predictions of the 2 accounts was proposed by Perruchet (1985). In this paradigm, E2 randomly follows E1 only half of the time on average, a probability that is known to participants. When the preceding run goes from a long sequence of E1 alone to a long sequence of E1-E2 pairs, associative strength should increase, whereas conscious expectancy for E2 should decrease in keeping with the gambler's fallacy. This article reviews the studies making use of the paradigm in the classical conditioning domain, and the extension of the same logic to a few other experimental situations. Overall, overt behavior has been found to change in line with associative strength, and in opposition to conscious expectancy, attesting to an empirical dissociation of automatic and control processes within a single preparation. The paradigm, however, is endowed with a number of tricky methodological issues, which are examined each in turn. Although some of these issues call for further research, a tentative conclusion is that the effect provides evidence for automatic link formation processes, the existence of which has been recently denied in the "propositional" account of learning. (c) 2015 APA, all rights reserved).

  1. Dynamical pattern formation in a low-concentration magnetorheological fluid under two orthogonal sinusoidal fields

    International Nuclear Information System (INIS)

    Yépez, L.D.; Carrillo, J.L.; Donado, F.; Sausedo-Solorio, J.M.; Miranda-Romagnoli, P.

    2016-01-01

    The dynamical pattern formation of clusters of magnetic particles in a low-concentration magnetorheological fluid, under the influence of a superposition of two perpendicular sinusoidal fields, is studied experimentally. By varying the frequency and phase shift of the perpendicular fields, this configuration enables us to experimentally analyze a wide range of field configurations, including the case of a pure rotating field and the case of an oscillating unidirectional field. The fields are applied parallel to the horizontal plane where the fluid lies or in the vertical plane. For fields applied in the horizontal plane, we observed that, when the ratio of the frequencies increases, the average cluster size exhibits a kind of periodic resonances. When the phase shift between the fields is varied, the average chain length reaches maximal values for the cases of the rotating field and the unidirectional case. We analyze and discuss these results in terms of a weighted average of the time-dependent Mason number. In the case of a rotating field on the vertical plane, we also observe that the competition between the magnetic and the viscous forces determines the average cluster size. We show that this configuration generates a series of physically meaningful self-organization of clusters and transport phenomena. - Highlights: • A weighted average of the time-dependent Mason number is proposed. • The self-propelling clusters appear when a vertical rotating magnetic field is applied. • The largest average chain lengths are reached when frequencies are multiples one another. • Rotating and unidirectional alternating fields produce the largest average chain length values.

  2. Dynamical pattern formation in a low-concentration magnetorheological fluid under two orthogonal sinusoidal fields

    Energy Technology Data Exchange (ETDEWEB)

    Yépez, L.D.; Carrillo, J.L. [Instituto de Física de la Universidad Autónoma de Puebla, Ciudad Universitaria, Edif. 110 A, Puebla 72570 (Mexico); Donado, F.; Sausedo-Solorio, J.M.; Miranda-Romagnoli, P. [Instituto de Ciencias Básicas e Ingeniería Universidad Autónoma del Estado de Hidalgo, Pachuca 42090, Pachuca (Mexico)

    2016-06-15

    The dynamical pattern formation of clusters of magnetic particles in a low-concentration magnetorheological fluid, under the influence of a superposition of two perpendicular sinusoidal fields, is studied experimentally. By varying the frequency and phase shift of the perpendicular fields, this configuration enables us to experimentally analyze a wide range of field configurations, including the case of a pure rotating field and the case of an oscillating unidirectional field. The fields are applied parallel to the horizontal plane where the fluid lies or in the vertical plane. For fields applied in the horizontal plane, we observed that, when the ratio of the frequencies increases, the average cluster size exhibits a kind of periodic resonances. When the phase shift between the fields is varied, the average chain length reaches maximal values for the cases of the rotating field and the unidirectional case. We analyze and discuss these results in terms of a weighted average of the time-dependent Mason number. In the case of a rotating field on the vertical plane, we also observe that the competition between the magnetic and the viscous forces determines the average cluster size. We show that this configuration generates a series of physically meaningful self-organization of clusters and transport phenomena. - Highlights: • A weighted average of the time-dependent Mason number is proposed. • The self-propelling clusters appear when a vertical rotating magnetic field is applied. • The largest average chain lengths are reached when frequencies are multiples one another. • Rotating and unidirectional alternating fields produce the largest average chain length values.

  3. Star Formation In the Galaxy and the Fluctuating UV Radiation Field

    Science.gov (United States)

    Hollenbach, David; Parravano, Antonio; McKee, Christopher H.; DeVincenzi, D. (Technical Monitor)

    2002-01-01

    We examine the formation of massive stars in the Galaxy, the resultant fluctuating UV (ultraviolet) radiation field, and the effect of this field on the star-forming interstellar medium. There are substantial fluctuations of the UV radiation field in space (scales of 100's of parsecs) and time (time-scales of order 100 million years). The FUV (far ultraviolet) (6 eV less than hv less than 13.6 eV) field and the pressure determines whether the thermal balance of the neutral gas results in cold clouds or warm (T approx. 10(exp 4) K) neutral medium. We show how to calculate the average fractions of the gas in the cold and warm phases when the interstellar gas is subject to this fluctuating FUV field. The knowledge of how these fractions depend on the gas properties and on the FUV sources is a basic step in building a model of the large scale behavior of the ISM (interstellar medium) and the mutual relation between the ISM and the star formation rate.

  4. Rigid format alter packets for the analysis of electromagnetic field problems

    Science.gov (United States)

    Spreeuw, E.; Reefman, R. J. B.

    1975-01-01

    The computer program NASTRAN is used to solve electromagnetic field problems. The diffusion equation and the boundary conditions valid for problems of these kinds together with a replacing potential energy function are given. The extent to which an analogy with finite element displacement and temperature approaches holds is indicated. The outputting of complex quantities is made possible after adjustment of standard rigid format 1 input data blocks to module SDR2. The applications made involve the study of the proximity effect in a system of three parallel conductors and the analysis of the magnetic field in the vicinity of the points of contact in circuit breakers.

  5. Effects of static magnetic fields on bone formation in rat osteoblast cultures.

    Science.gov (United States)

    Yamamoto, Y; Ohsaki, Y; Goto, T; Nakasima, A; Iijima, T

    2003-12-01

    Although the promotional effects on osteoblasts of pulsed electromagnetic fields have been well-demonstrated, the effects of static magnetic fields (SMF) remain unclear; nevertheless, magnets have been clinically used as a 'force source' in various orthodontic treatments. We undertook the present investigation to study the effects of SMF on osteoblastic differentiation, proliferation, and bone nodule formation using a rat calvaria cell culture. During a 20-day culture, the values of the total area and the number and average size of bone nodules showed high levels in the presence of SMF. In the matrix development and mineralization stages, the calcium content in the matrix and two markers of osteoblastic phenotype (alkaline phosphatase and osteocalcin) also showed a significant increase. Accordingly, these findings suggest that SMF stimulates bone formation by promoting osteoblastic differentiation and/or activation.

  6. Development and field testing of satellite-linked fluorometers for marine mammals

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset includes telemetry data related to the development and testing of an animal-borne satellite-linked fluorometer tag, used on northern fur seals and...

  7. STAR FORMATION IN THE CHANDRA DEEP FIELD SOUTH: OBSERVATIONS CONFRONT SIMULATIONS

    International Nuclear Information System (INIS)

    Damen, Maaike; Franx, Marijn; Foerster Schreiber, Natascha M.; Labbe, Ivo; Toft, Sune; Van Dokkum, Pieter G.; Wuyts, Stijn

    2009-01-01

    We investigate the star formation history of the universe using FIREWORKS, a multiwavelength survey of the Chandra Deep Field South. We study the evolution of the specific star formation rate (sSFR) with redshift in different mass bins from z = 0 to z ∼ 3. We find that the sSFR increases with redshift for all masses. The logarithmic increase of the sSFR with redshift is nearly independent of mass, but this cannot yet be verified at the lowest-mass bins at z>0.8, due to incompleteness. We convert the sSFRs to a dimensionless growth rate to facilitate a comparison with a semianalytic galaxy formation model that was implemented on the Millennium Simulation. The model predicts that the growth rates and sSFRs increase similarly with redshift for all masses, consistent with the observations. However, we find that for all masses, the inferred observed growth rates increase more rapidly with redshift than the model predictions. We discuss several possible causes for this discrepancy, ranging from field-to-field variance, conversions to SFR, and shape of the initial mass function. We find that none of these can solve the discrepancy completely. We conclude that the models need to be adapted to produce the steep increase in growth rate between redshift z = 0 and z = 1.

  8. Electric field formation in three different plasmas: A fusion reactor, arc discharge, and the ionosphere

    Science.gov (United States)

    Lee, Kwan Chul

    2017-11-01

    Three examples of electric field formation in the plasma are analyzed based on a new mechanism driven by ion-neutral collisions. The Gyro-Center Shift analysis uses the iteration of three equations including perpendicular current induced by the momentum exchange between ions and neutrals when there is asymmetry over the gyro-motion. This method includes non-zero divergence of current that leads the solution of time dependent state. The first example is radial electric field formation at the boundary of the nuclear fusion device, which is a key factor in the high-confinement mode operation of future fusion reactors. The second example is the reversed rotation of the arc discharge cathode spot, which has been a mysterious subject for more than one hundred years. The third example is electric field formations in the earth's ionosphere, which are important components of the equatorial electrojet and black aurora. The use of one method that explains various examples from different plasmas is reported, along with a discussion of the applications.

  9. THE INFLUENCE OF MAGNETIC FIELD GEOMETRY ON THE FORMATION OF CLOSE-IN EXOPLANETS

    Energy Technology Data Exchange (ETDEWEB)

    Simon, Jacob B., E-mail: jbsimon.astro@gmail.com [Department of Space Studies, Southwest Research Institute, Boulder, CO 80302 (United States)

    2016-08-20

    Approximately half of Sun-like stars harbor exoplanets packed within a radius of ∼0.3 au, but the formation of these planets and why they form in only half of known systems are still not well understood. We employ a one-dimensional steady-state model to gain physical insight into the origin of these close-in exoplanets. We use Shakura and Sunyaev α values extracted from recent numerical simulations of protoplanetary disk accretion processes in which the magnitude of α , and thus the steady-state gas surface density, depend on the orientation of large-scale magnetic fields with respect to the disk’s rotation axis. Solving for the metallicity as a function of radius, we find that for fields anti-aligned with the rotation axis, the inner regions of our model disk often fall within a region of parameter space that is not suitable for planetesimal formation, whereas in the aligned case, the inner disk regions are likely to produce planetesimals through some combination of streaming instability and gravitational collapse, though the degree to which this is true depends on the assumed parameters of our model. More robustly, the aligned field case always produces higher concentrations of solids at small radii compared to the anti-aligned case. In the in situ formation model, this bimodal distribution of solid enhancement leads directly to the observed dichotomy in exoplanet orbital distances.

  10. Magnetic Axis Drift and Magnetic Spot Formation in Neutron Stars with Toroidal Fields

    Science.gov (United States)

    Gourgouliatos, Konstantinos N.; Hollerbach, Rainer

    2018-01-01

    We explore magnetic field configurations that lead to the formation of magnetic spots on the surface of neutron stars and the displacement of the magnetic dipole axis. We find that a toroidally dominated magnetic field is essential for the generation of a single spot with a strong magnetic field. Once a spot forms, it survives for several million years, even after the total magnetic field has decayed significantly. We find that the dipole axis is not stationary with respect to the neutron star’s surface and does not in general coincide with the location of the magnetic spot. This is due to non-axisymmetric instabilities of the toroidal field that displace the poloidal dipole axis at rates that may reach 0.°4 per century. A misaligned poloidal dipole axis with the toroidal field leads to more significant displacement of the dipole axis than the fully aligned case. Finally we discuss the evolution of neutron stars with such magnetic fields on the P{--}\\dot{P} diagram and the observational implications. We find that neutron stars spend a very short time before they cross the Death Line of the P{--}\\dot{P} diagram, compared to their characteristic ages. Moreover, the maximum intensity of their surface magnetic field is substantially higher than the dipole component of the field. We argue that SGR 0418+5729 could be an example of this type of behavior, having a weak dipole field, yet hosting a magnetic spot responsible for its magnetar behavior. The evolution on the pulse profile and braking index of the Crab pulsar, which are attributed to an increase of its obliquity, are compatible with the anticipated drift of the magnetic axis.

  11. Physical simulation of gas reservoir formation in the Liwan 3-1 deep-water gas field in the Baiyun sag, Pearl River Mouth Basin

    Directory of Open Access Journals (Sweden)

    Gang Gao

    2015-01-01

    Full Text Available To figure out the process and controlling factors of gas reservoir formation in deep-waters, based on an analysis of geological features, source of natural gas and process of reservoir formation in the Liwan 3-1 gas field, physical simulation experiment of the gas reservoir formation process has been performed, consequently, pattern and features of gas reservoir formation in the Baiyun sag has been found out. The results of the experiment show that: ① the formation of the Liwan 3-1 faulted anticline gas field is closely related to the longstanding active large faults, where natural gas is composed of a high proportion of hydrocarbons, a small amount of non-hydrocarbons, and the wet gas generated during highly mature stage shows obvious vertical migration signs; ② liquid hydrocarbons associated with natural gas there are derived from source rock of the Enping & Zhuhai Formation, whereas natural gas comes mainly from source rock of the Enping Formation, and source rock of the Wenchang Formation made a little contribution during the early Eocene period as well; ③ although there was gas migration and accumulation, yet most of the natural gas mainly scattered and dispersed due to the stronger activity of faults in the early period; later as fault activity gradually weakened, gas started to accumulate into reservoirs in the Baiyun sag; ④ there is stronger vertical migration of oil and gas than lateral migration, and the places where fault links effective source rocks with reservoirs are most likely for gas accumulation; ⑤ effective temporal-spatial coupling of source-fault-reservoir in late stage is the key to gas reservoir formation in the Baiyun sag; ⑥ the nearer the distance from a trap to a large-scale fault and hydrocarbon source kitchen, the more likely gas may accumulate in the trap in late stage, therefore gas accumulation efficiency is much lower for the traps which are far away from large-scale faults and hydrocarbon source

  12. Magnetic field formation in the Milky Way like disc galaxies of the Auriga project

    Science.gov (United States)

    Pakmor, Rüdiger; Gómez, Facundo A.; Grand, Robert J. J.; Marinacci, Federico; Simpson, Christine M.; Springel, Volker; Campbell, David J. R.; Frenk, Carlos S.; Guillet, Thomas; Pfrommer, Christoph; White, Simon D. M.

    2017-08-01

    The magnetic fields observed in the Milky Way and nearby galaxies appear to be in equipartition with the turbulent, thermal and cosmic ray energy densities, and hence are expected to be dynamically important. However, the origin of these strong magnetic fields is still unclear, and most previous attempts to simulate galaxy formation from cosmological initial conditions have ignored them altogether. Here, we analyse the magnetic fields predicted by the simulations of the Auriga Project, a set of 30 high-resolution cosmological zoom simulations of Milky Way like galaxies, carried out with a moving-mesh magnetohydrodynamics code and a detailed galaxy formation physics model. We find that the magnetic fields grow exponentially at early times owing to a small-scale dynamo with an e-folding time of roughly 100 Myr in the centre of haloes until saturation occurs around z = 2-3, when the magnetic energy density reaches about 10 per cent of the turbulent energy density with a typical strength of 10-50 {μ G}. In the galactic centres, the ratio between magnetic and turbulent energies remains nearly constant until z = 0. At larger radii, differential rotation in the discs leads to linear amplification that typically saturates around z = 0.5-0. The final radial and vertical variations of the magnetic field strength can be well described by two joint exponential profiles, and are in good agreement with observational constraints. Overall, the magnetic fields have only little effect on the global evolution of the galaxies as it takes too long to reach equipartition. We also demonstrate that our results are well converged with numerical resolution.

  13. Measuring Plasma Formation Field Strength and Current Loss in Pulsed Power Diodes

    Energy Technology Data Exchange (ETDEWEB)

    Johnston, Mark D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Advanced Radiographic Technologies Dept.; Patel, Sonal G. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Advanced Radiographic Technologies Dept.; Falcon, Ross Edward [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Advanced Radiographic Technologies Dept.; Cartwright, Keith [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Advanced Radiographic Technologies Dept.; Kiefer, Mark L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Advanced Radiographic Technologies Dept.; Cuneo, Michael E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Advanced Radiographic Technologies Dept.; Maron, Yitzhak [Weizmann Inst. of Science, Rehovot (Israel)

    2017-11-01

    This LDRD investigated plasma formation, field strength, and current loss in pulsed power diodes. In particular the Self-Magnetic Pinch (SMP) e-beam diode was studied on the RITS-6 accelerator. Magnetic fields of a few Tesla and electric fields of several MV/cm were measured using visible spectroscopy techniques. The magnetic field measurements were then used to determine the current distribution in the diode. This distribution showed that significant beam current extends radially beyond the few millimeter x-ray focal spot diameter. Additionally, shielding of the magnetic field due to dense electrode surface plasmas was observed, quantified, and found to be consistent with the calculated Spitzer resistivity. In addition to the work on RITS, measurements were also made on the Z-machine looking to quantify plasmas within the power flow regions. Measurements were taken in the post-hole convolute and final feed gap regions on Z. Dopants were applied to power flow surfaces and measured spectroscopically. These measurements gave species and density/temperature estimates. Preliminary B-field measurements in the load region were attempted as well. Finally, simulation work using the EMPHASIS, electromagnetic particle in cell code, was conducted using the Z MITL conditions. The purpose of these simulations was to investigate several surface plasma generations models under Z conditions for comparison with experimental data.

  14. The Effects of Magnetic Fields and Protostellar Feedback on Low-mass Cluster Formation

    Science.gov (United States)

    Cunningham, Andrew J.; Krumholz, Mark R.; McKee, Christopher F.; Klein, Richard I.

    2018-01-01

    We present a large suite of simulations of the formation of low-mass star clusters. Our simulations include an extensive set of physical processes - magnetohydrodynamics, radiative transfer, and protostellar outflows - and span a wide range of virial parameters and magnetic field strengths. Comparing the outcomes of our simulations to observations, we find that simulations remaining close to virial balance throughout their history produce star formation efficiencies and initial mass function (IMF) peaks that are stable in time and in reasonable agreement with observations. Our results indicate that small-scale dissipation effects near the protostellar surface provide a feedback loop for stabilizing the star formation efficiency. This is true regardless of whether the balance is maintained by input of energy from large scale forcing or by strong magnetic fields that inhibit collapse. In contrast, simulations that leave virial balance and undergo runaway collapse form stars too efficiently and produce an IMF that becomes increasingly top-heavy with time. In all cases we find that the competition between magnetic flux advection toward the protostar and outward advection due to magnetic interchange instabilities, and the competition between turbulent amplification and reconnection close to newly-formed protostars renders the local magnetic field structure insensitive to the strength of the large-scale field, ensuring that radiation is always more important than magnetic support in setting the fragmentation scale and thus the IMF peak mass. The statistics of multiple stellar systems are similarly insensitive to variations in the initial conditions and generally agree with observations within the range of statistical uncertainty.

  15. The effects of magnetic fields and protostellar feedback on low-mass cluster formation

    Science.gov (United States)

    Cunningham, Andrew J.; Krumholz, Mark R.; McKee, Christopher F.; Klein, Richard I.

    2018-05-01

    We present a large suite of simulations of the formation of low-mass star clusters. Our simulations include an extensive set of physical processes - magnetohydrodynamics, radiative transfer, and protostellar outflows - and span a wide range of virial parameters and magnetic field strengths. Comparing the outcomes of our simulations to observations, we find that simulations remaining close to virial balance throughout their history produce star formation efficiencies and initial mass function (IMF) peaks that are stable in time and in reasonable agreement with observations. Our results indicate that small-scale dissipation effects near the protostellar surface provide a feedback loop for stabilizing the star formation efficiency. This is true regardless of whether the balance is maintained by input of energy from large-scale forcing or by strong magnetic fields that inhibit collapse. In contrast, simulations that leave virial balance and undergo runaway collapse form stars too efficiently and produce an IMF that becomes increasingly top heavy with time. In all cases, we find that the competition between magnetic flux advection towards the protostar and outward advection due to magnetic interchange instabilities, and the competition between turbulent amplification and reconnection close to newly formed protostars renders the local magnetic field structure insensitive to the strength of the large-scale field, ensuring that radiation is always more important than magnetic support in setting the fragmentation scale and thus the IMF peak mass. The statistics of multiple stellar systems are similarly insensitive to variations in the initial conditions and generally agree with observations within the range of statistical uncertainty.

  16. Molecular Dynamics Simulation of Cross-Linked Epoxy Polymers: the Effect of Force Field on the Estimation of Properties

    OpenAIRE

    B. Arab; A. Shokuhfar

    2013-01-01

    In this paper, the molecular dynamics method was used to calculate the physical and mechanical properties of the cross-linked epoxy polymer composed of diglycidyl ether of bisphenol-A (DGEBA) as resin and diethylenetriamine (DETA) as curing agent. Calculation of the properties was performed using the constant-strain (static) approach. A series of independent simulations were carried out based on four widely used force fields; COMPASS, PCFF, UFF and Dreiding. Proper comparisons between the res...

  17. Numerical Study of Field-reversed Configurations: The Formation and Ion Spin-up

    International Nuclear Information System (INIS)

    Belova, E.V.; Davidson, R.C.; Ji, H.; Yamada, M.; Cothran, C.D.; Brown, M.R.; Schaffer, M.J.

    2005-01-01

    Results of three-dimensional numerical simulations of field-reversed configurations (FRCs) are presented. Emphasis of this work is on the nonlinear evolution of magnetohydrodynamic (MHD) instabilities in kinetic FRCs, and the new FRC formation method by counter-helicity spheromak merging. Kinetic simulations show nonlinear saturation of the n = 1 tilt mode, where n is the toroidal mode number. The n = 2 and n = 3 rotational modes are observed to grow during the nonlinear phase of the tilt instability due to the ion spin-up in the toroidal direction. The ion toroidal spin-up is shown to be related to the resistive decay of the internal flux, and the resulting loss of particle confinement. Three-dimensional MHD simulations of counter-helicity spheromak merging and FRC formation show good qualitative agreement with results from the SSX-FRC experiment. The simulations show formation of an FRC in about 20-30 Alfven times for typical experimental parameters. The growth rate of the n = 1 tilt mode is shown to be significantly reduced compared to the MHD growth rate due to the large plasma viscosity and field-line-tying effects

  18. Stochastic Reconstruction and Interpolation of Precipitation Fields Using Combined Information of Commercial Microwave Links and Rain Gauges

    Science.gov (United States)

    Haese, B.; Hörning, S.; Chwala, C.; Bárdossy, A.; Schalge, B.; Kunstmann, H.

    2017-12-01

    For the reconstruction and interpolation of precipitation fields, we present the application of a stochastic approach called Random Mixing. Generated fields are based on a data set consisting of rain gauge observations and path-averaged rain rates estimated using Commercial Microwave Link (CML) derived information. Precipitation fields are received as linear combination of unconditional spatial random fields, where the spatial dependence structure is described by copulas. The weights of the linear combination are optimized such that the observations and the spatial structure of the precipitation observations are reproduced. The innovation of the approach is that this strategy enables the simulation of ensembles of precipitation fields of any size. Each ensemble member is in concordance with the observed path-averaged CML derived rain rates and additionally reflects the observed rainfall variability along the CML paths. The ensemble spread allows additionally an estimation of the uncertainty of the reconstructed precipitation fields. The method is demonstrated both for a synthetic data set and a real-world data set in South Germany. While the synthetic example allows an evaluation against a known reference, the second example demonstrates the applicability for real-world observations. Generated precipitation fields of both examples reproduce the spatial precipitation pattern in good quality. A performance evaluation of Random Mixing compared to Ordinary Kriging demonstrates an improvement of the reconstruction of the observed spatial variability. Random Mixing is concluded to be a beneficial new approach for the provision of precipitation fields and ensembles of them, in particular when different measurement types are combined.

  19. Formation of carbonate pipes in the northern Okinawa Trough linked to strong sulfate exhaustion and iron supply

    Science.gov (United States)

    Peng, Xiaotong; Guo, Zixiao; Chen, Shun; Sun, Zhilei; Xu, Hengchao; Ta, Kaiwen; Zhang, Jianchao; Zhang, Lijuan; Li, Jiwei; Du, Mengran

    2017-05-01

    The microbial anaerobic oxidation of methane (AOM), a key biogeochemical process that consumes substantial amounts of methane produced in seafloor sediments, can lead to the formation of carbonate deposits at or beneath the sea floor. Although Fe oxide-driven AOM has been identified in cold seep sediments, the exact mode by which it may influence the formation of carbonate deposits remains poorly understood. Here, we characterize the morphology, petrology and geochemistry of a methane-derived Fe-rich carbonate pipe in the northern Okinawa Trough (OT). We detect abundant authigenic pyrites, as well as widespread trace Fe, within microbial mat-like carbonate veins in the pipe. The in situ δ34S values of these pyrites range from -3.9 to 31.6‰ (VCDT), suggesting a strong consumption of seawater sulfate by sulfate-driven AOM at the bottom of sulfate reduction zone. The positive δ56Fe values of pyrite and notable enrichment of Fe in the OT pipe concurrently indicate that the pyrites are primarily derived from Fe oxides in deep sediments. We propose that the Fe-rich carbonate pipe formed at the bottom of sulfate reduction zone, below which Fe-driven AOM, rather than Fe-oxide reduction coupled to organic matter degradation, might be responsible for the abundantly available Fe2+ in the fluids from which pyrites precipitated. The Fe-rich carbonate pipe described in this study probably represents the first fossil example of carbonate deposits linked to Fe-driven AOM. Because Fe-rich carbonate deposits have also been found at other cold seeps worldwide, we infer that similar processes may play an essential role in biogeochemical cycling of sub-seafloor methane and Fe at continental margins.

  20. Unveiling the Role of the Magnetic Field at the Smallest Scales of Star Formation

    Energy Technology Data Exchange (ETDEWEB)

    Hull, Charles L. H.; Mocz, Philip; Burkhart, Blakesley; Goodman, Alyssa A.; Hernquist, Lars [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Girart, Josep M. [Institut de Ciències de l’Espai (CSIC-IEEC), Campus UAB, Carrer de Can Magrans S/N, E-08193 Cerdanyola del Vallès, Catalonia (Spain); Cortés, Paulo C. [National Radio Astronomy Observatory, Charlottesville, VA 22903 (United States); Springel, Volker [Heidelberger Institut für Theoretische Studien, Schloss-Wolfsbrunnenweg 35, D-69118 Heidelberg (Germany); Li, Zhi-Yun [Department of Astronomy, University of Virginia, Charlottesville, VA 22903 (United States); Lai, Shih-Ping, E-mail: chat.hull@cfa.harvard.edu [Institute of Astronomy and Department of Physics, National Tsing Hua University, 101 Section 2 Kuang Fu Road, 30013 Hsinchu, Taiwan (China)

    2017-06-20

    We report Atacama Large Millimeter/submillimeter Array (ALMA) observations of polarized dust emission from the protostellar source Ser-emb 8 at a linear resolution of 140 au. Assuming models of dust-grain alignment hold, the observed polarization pattern gives a projected view of the magnetic field structure in this source. Contrary to expectations based on models of strongly magnetized star formation, the magnetic field in Ser-emb 8 does not exhibit an hourglass morphology. Combining the new ALMA data with previous observational studies, we can connect magnetic field structure from protostellar core (∼80,000 au) to disk (∼100 au) scales. We compare our observations with four magnetohydrodynamic gravo-turbulence simulations made with the AREPO code that have initial conditions ranging from super-Alfvénic (weakly magnetized) to sub-Alfvénic (strongly magnetized). These simulations achieve the spatial dynamic range necessary to resolve the collapse of protostars from the parsec scale of star-forming clouds down to the ∼100 au scale probed by ALMA. Only in the very strongly magnetized simulation do we see both the preservation of the field direction from cloud to disk scales and an hourglass-shaped field at <1000 au scales. We conduct an analysis of the relative orientation of the magnetic field and the density structure in both the Ser-emb 8 ALMA observations and the synthetic observations of the four AREPO simulations. We conclude that the Ser-emb 8 data are most similar to the weakly magnetized simulations, which exhibit random alignment, in contrast to the strongly magnetized simulation, where the magnetic field plays a role in shaping the density structure in the source. In the weak-field case, it is turbulence—not the magnetic field—that shapes the material that forms the protostar, highlighting the dominant role that turbulence can play across many orders of magnitude in spatial scale.

  1. Liquid-liquid phase separation and cluster formation at deposition of metals under inhomogeneous magnetic field

    Science.gov (United States)

    Gorobets, O. Yu; Gorobets, Yu I.; Rospotniuk, V. P.; Grebinaha, V. I.; Kyba, A. A.

    2017-10-01

    The formation and dynamic of expansion and deformation of the liquid-liquid interface of an electrolyte at deposition of metals at the surface of the magnetized steel ball is considered in this paper. The electrochemical processes were investigated in an external magnetic field directed at an arbitrary angle to the force of gravity. These processes are accompanied by the formation of effectively paramagnetic clusters of electrochemical products - magnions. Tyndall effect was used for detection of the presence of magnions near the magnetized steel electrode in a solution. The shape of the interface separating the regions with different concentration of magnions, i.e. different magnetic susceptibilities, was described theoretically based on the equation of hydrostatic equilibrium which takes into account magnetic, hydrostatic and osmotic pressures.

  2. The History of Education in Brazil: The Formation of the Field and Theoretical Influences

    Directory of Open Access Journals (Sweden)

    Marisa Bittar

    2016-01-01

    Full Text Available This article is concerned with the History of Education in Brazil in two key areas: the disciplinary field and the research field. As a discipline, the History of Education has formed a part of the school curriculum since the beginning of the 20th century. As a research field, it gained impetus in the 60s with the setting up of post-graduate courses and became one of the most consolidated areas of Brazilian education. In the light of this, there is a discussion about academic organisation and an attempt is being made to show how the field is characterised by theoretical renewal and is facing two key challenges: cultural exchanges involving the use of English and a recognition of the value of the History of Education as a discipline in the light of the fact that less space is being devoted to it in teacher-training curricula. How to reference this article Bittar, M., & Ferreira Jr., A. (2016. The History of Education in Brazil: The Formation of the Field and Theoretical Influences. Espacio, Tiempo y Educación, 3(1, 61-84. doi: http://dx.doi.org/10.14516/ete.2016.003.001.5

  3. THE IMPACT OF THERMODYNAMICS ON GRAVITATIONAL COLLAPSE: FILAMENT FORMATION AND MAGNETIC FIELD AMPLIFICATION

    Energy Technology Data Exchange (ETDEWEB)

    Peters, Thomas; Klessen, Ralf S.; Federrath, Christoph; Smith, Rowan J. [Zentrum fuer Astronomie, Institut fuer Theoretische Astrophysik, Universitaet Heidelberg, Albert-Ueberle-Str. 2, D-69120 Heidelberg (Germany); Schleicher, Dominik R. G. [Institut fuer Astrophysik, Georg-August-Universitaet, Friedrich-Hund-Platz 1, D-37077 Goettingen (Germany); Banerjee, Robi [Hamburger Sternwarte, Gojenbergsweg 112, D-21029 Hamburg (Germany); Sur, Sharanya, E-mail: tpeters@physik.uzh.ch [Raman Research Institute, C. V. Raman Avenue, Sadashivnagar, Bangalore 560080 (India)

    2012-12-01

    Stars form by the gravitational collapse of interstellar gas. The thermodynamic response of the gas can be characterized by an effective equation of state. It determines how gas heats up or cools as it gets compressed, and hence plays a key role in regulating the process of stellar birth on virtually all scales, ranging from individual star clusters up to the galaxy as a whole. We present a systematic study of the impact of thermodynamics on gravitational collapse in the context of high-redshift star formation, but argue that our findings are also relevant for present-day star formation in molecular clouds. We consider a polytropic equation of state, P = k{rho}{sup {Gamma}}, with both sub-isothermal exponents {Gamma} < 1 and super-isothermal exponents {Gamma} > 1. We find significant differences between these two cases. For {Gamma} > 1, pressure gradients slow down the contraction and lead to the formation of a virialized, turbulent core. Weak magnetic fields are strongly tangled and efficiently amplified via the small-scale turbulent dynamo on timescales corresponding to the eddy-turnover time at the viscous scale. For {Gamma} < 1, on the other hand, pressure support is not sufficient for the formation of such a core. Gravitational contraction proceeds much more rapidly and the flow develops very strong shocks, creating a network of intersecting sheets and extended filaments. The resulting magnetic field lines are very coherent and exhibit a considerable degree of order. Nevertheless, even under these conditions we still find exponential growth of the magnetic energy density in the kinematic regime.

  4. Bulgeless galaxies in the COSMOS field: environment and star formation evolution at z < 1

    Science.gov (United States)

    Grossi, Marco; Fernandes, Cristina A. C.; Sobral, David; Afonso, José; Telles, Eduardo; Bizzocchi, Luca; Paulino-Afonso, Ana; Matute, Israel

    2018-03-01

    Combining the catalogue of galaxy morphologies in the COSMOS field and the sample of H α emitters at redshifts z = 0.4 and z = 0.84 of the HiZELS survey, we selected ˜ 220 star-forming bulgeless systems (Sérsic index n ≤ 1.5) at both epochs. We present their star formation properties and we investigate their contribution to the star formation rate function (SFRF) and global star formation rate density (SFRD) at z comparison, we also analyse H α emitters with more structurally evolved morphologies that we split into two classes according to their Sérsic index n: intermediate (1.5 3). At both redshifts, the SFRF is dominated by the contribution of bulgeless galaxies and we show that they account for more than 60 per cent of the cosmic SFRD at z systems. Star-forming bulgeless systems are mostly located in regions of low to intermediate galaxy densities (Σ ˜ 1-4 Mpc-2) typical of field-like and filament-like environments and their specific star formation rates (sSFRs) do not appear to vary strongly with local galaxy density. Only few bulgeless galaxies in our sample have high (sSFR > 10-9 yr-1) and these are mainly low-mass systems. Above M* ˜ 1010 M⊙ bulgeless are evolving at a `normal' rate (10-9 yr-1 < sSFR < 10-10 yr-1) and in the absence of an external trigger (i.e. mergers/strong interactions) they might not be able to develop a central classical bulge.

  5. Chemometric analysis reveals links in the formation of fragrant bio-molecules during agarwood (Aquilaria malaccensis) and fungal interactions.

    Science.gov (United States)

    Sen, Supriyo; Dehingia, Madhusmita; Talukdar, Narayan Chandra; Khan, Mojibur

    2017-03-14

    Fragrant agarwood, arguably the costliest wood in the world, is formed by plant-fungal interactions in Aquilaria spp. However, very little is known about this fragrant outcome of interaction. Therefore, mimicking the ancient traditions of agarwood production in Assam (Northeast India), a chemometric assessment of the agarwood-fungus interaction was made by chemical profiling (GC-MS) coupled with statistical analysis (principal component, correlation network analysis) across three platforms, viz. callus, juvenile plants and resinous wood-chips with an associated Fusarium. In the study of callus-fungus interaction, increased accumulation of key aroma compounds such as pentatriacontane {fold change (log2FC) = 3.47)}, 17-pentatriacontene (log2FC = 2.95), tetradecane, 2-methyl- (log2FC = 1.10) over callus and activation of pathways related to defense and secondary metabolism indicated links to aroma production. Study on fungal interactions in juvenile plants and resinous wood-chips indicated formation of terpenoid precursors (e.g. farnesol, geranylgeraniol acetate) and agarwood sesquiterpenes (e.g. agarospirol, γ-eudesmol). Correlation network analysis revealed the possible regulation of sesquiterpene biosynthesis involving squalene. Also a direct role of fungus in aroma (e.g. dodecane, 4-methyl-, tetracosane) was highlighted. Appearance of fragrant molecules unknown to agarwood during interaction featured as a new possibility for future research.

  6. Dwarf Galaxies with Gentle Star Formation and the Counts of Galaxies in the Hubble Deep Field

    OpenAIRE

    Campos, Ana

    1997-01-01

    In this paper the counts and colors of the faint galaxies observed in the Hubble Deep Field are fitted by means of simple luminosity evolution models that incorporate a numerous population of fading dwarfs. The observed color distribution of the very faint galaxies now allows us to put constraints on the star formation history in dwarfs. It is shown that the star-forming activity in these small systems has to proceed in a gentle way, i.e., through episodes where each one lasts much longer tha...

  7. Influence of initial seed distribution on the pattern formation of the phase field crystals

    Science.gov (United States)

    Starodumov, Ilya; Galenko, Peter; Kropotin, Nikolai; Alexandrov, Dmitri V.

    2017-11-01

    The process of crystal growth can be expressed as a transition of atomic structure to a finally stable state or to a metastable state. In the Phase Field Crystal Model (PFC-model) these states are described by regular distributions of the atomic density. Getting the system into any metastable condition may be caused by the peculiarities of the computational domain, initial and boundary conditions. However, an important factor in the formation of the crystal structure can be the initial disturbance. In the report we show how different types of initial disturbance can change the finally stable state of crystal structure in equilibrium.

  8. Modeling the legal field of formation of socially responsible conduct among pharmacy specialists

    Directory of Open Access Journals (Sweden)

    N. O. Tkachenko

    2018-03-01

    Full Text Available Observation of legal and legislative standards of the company activities is the fundamental principle of social responsibility (SR. The results of the literature analysis show the lack of fundamental research of regulatory and legal support of formation of socially responsible conduct of pharmacists (SRCPh. AIM: modeling the legal framework and determining the completeness and content of the current regulatory and legal framework on formation of a system of SRCPh throughout the professional lifespan development. Materials and methods. The materials of the study were national and international regulatory legal acts, regulating SR, the activities of pharmaceutical organizations (PhO and getting a pharmaceutical education. During the work, such methods as searching information, systematization, content analysis, comparison and generalization were used. During the investigation, we summarized the legal framework that in various aspects forms the socially responsible conduct of the pharmacists throughout the lifespan professional development; and a model of the legal field of this process was formed. A content analysis of this regulatory framework in aspect of responsibility of the PhO and pharmacists with a description of the problem legal questions in the context of SR was carried out. In this article, attention is paid to the basic level of the legal field, within which general principles of social relations are formed in all spheres of the economy. Conclusions. We have formed a model of the legal field formation of a SRCPh system throughout the professional lifespan development. The model is a complex, multilevel system. The regulatory framework in the model is distributed according to two criteria (hierarchical and regulating relations in the system of socially responsible conduct of the pharmacists and includes 27 basic normative legal acts. We have identified problems in the legal field of the basic level of SRCPh formation: the indistinctness

  9. Spontaneous membrane formation and self-encapsulation of active rods in an inhomogeneous motility field

    Science.gov (United States)

    Grauer, Jens; Löwen, Hartmut; Janssen, Liesbeth M. C.

    2018-02-01

    We study the collective dynamics of self-propelled rods in an inhomogeneous motility field. At the interface between two regions of constant but different motility, a smectic rod layer is spontaneously created through aligning interactions between the active rods, reminiscent of an artificial, semipermeable membrane. This "active membrane" engulfes rods which are locally trapped in low-motility regions and thereby further enhances the trapping efficiency by self-organization, an effect which we call "self-encapsulation." Our results are gained by computer simulations of self-propelled rod models confined on a two-dimensional planar or spherical surface with a stepwise constant motility field, but the phenomenon should be observable in any geometry with sufficiently large spatial inhomogeneity. We also discuss possibilities to verify our predictions of active-membrane formation in experiments of self-propelled colloidal rods and vibrated granular matter.

  10. Implementation of data acquisition interface using on-board field-programmable gate array (FPGA) universal serial bus (USB) link

    International Nuclear Information System (INIS)

    Yussup, N.; Ibrahim, M. M.; Lombigit, L.; Rahman, N. A. A.; Zin, M. R. M.

    2014-01-01

    Typically a system consists of hardware as the controller and software which is installed in the personal computer (PC). In the effective nuclear detection, the hardware involves the detection setup and the electronics used, with the software consisting of analysis tools and graphical display on PC. A data acquisition interface is necessary to enable the communication between the controller hardware and PC. Nowadays, Universal Serial Bus (USB) has become a standard connection method for computer peripherals and has replaced many varieties of serial and parallel ports. However the implementation of USB is complex. This paper describes the implementation of data acquisition interface between a field-programmable gate array (FPGA) board and a PC by exploiting the USB link of the FPGA board. The USB link is based on an FTDI chip which allows direct access of input and output to the Joint Test Action Group (JTAG) signals from a USB host and a complex programmable logic device (CPLD) with a 24 MHz clock input to the USB link. The implementation and results of using the USB link of FPGA board as the data interfacing are discussed

  11. Implementation of data acquisition interface using on-board field-programmable gate array (FPGA) universal serial bus (USB) link

    International Nuclear Information System (INIS)

    Nolida Yussup; Maslina Mohd Ibrahim; Lojius Lombigit; Nur Aira Abdul Rahman; Muhammad Rawi Mohamed Zin

    2013-01-01

    Full-text: Typically a system consists of hardware as the controller and software which is installed in the personal computer (PC). In the effective nuclear detection, the hardware involves the detection setup and the electronics used, with the software consisting of analysis tools and graphical display on PC. A data acquisition interface is necessary to enable the communication between the controller hardware and PC. Nowadays, Universal Serial Bus (USB) has become a standard connection method for computer peripherals and has replaced many varieties of serial and parallel ports. However the implementation of USB is complex. This paper describes the implementation of data acquisition interface between a field-programmable gate array (FPGA) board and a PC by exploiting the USB link of the FPGA board. The USB link is based on an FTDI chip which allows direct access of input and output to the Joint Test Action Group (JTAG) signals from a USB host and a complex programmable logic device (CPLD) with a 24 MHz clock input to the USB link. The implementation and results of using the USB link of FPGA board as the data interfacing are discussed. (author)

  12. Implementation of data acquisition interface using on-board field-programmable gate array (FPGA) universal serial bus (USB) link

    Science.gov (United States)

    Yussup, N.; Ibrahim, M. M.; Lombigit, L.; Rahman, N. A. A.; Zin, M. R. M.

    2014-02-01

    Typically a system consists of hardware as the controller and software which is installed in the personal computer (PC). In the effective nuclear detection, the hardware involves the detection setup and the electronics used, with the software consisting of analysis tools and graphical display on PC. A data acquisition interface is necessary to enable the communication between the controller hardware and PC. Nowadays, Universal Serial Bus (USB) has become a standard connection method for computer peripherals and has replaced many varieties of serial and parallel ports. However the implementation of USB is complex. This paper describes the implementation of data acquisition interface between a field-programmable gate array (FPGA) board and a PC by exploiting the USB link of the FPGA board. The USB link is based on an FTDI chip which allows direct access of input and output to the Joint Test Action Group (JTAG) signals from a USB host and a complex programmable logic device (CPLD) with a 24 MHz clock input to the USB link. The implementation and results of using the USB link of FPGA board as the data interfacing are discussed.

  13. Effective boundary field theory for a Josephson junction chain with a weak link

    International Nuclear Information System (INIS)

    Giuliano, Domenico; Sodano, Pasquale

    2005-01-01

    We show that a finite Josephson junction (JJ) chain, ending with two bulk superconductors, and with a weak link at its center, may be regarded as a condensed matter realization of a two-boundary sine-Gordon model. Computing the partition function yields a remarkable analytic expression for the DC Josephson current as a function of the phase difference across the chain. We show that, in a suitable range of the chain parameters, there is a crossover of the DC Josephson current from a sinusoidal to a sawtooth behavior, which signals a transition from a regime where the boundary term is an irrelevant operator to a regime where it becomes relevant

  14. Temporal and spatial spectroscopy of the plasma formation in crossed electric and magnetic fields

    International Nuclear Information System (INIS)

    Miljevic, V.I.; Tosic, D.D.

    1980-01-01

    The formation of argon plasma in crossed electric and magnetic fields in a cylindrical diode with an incandescent cathode has been studied by means of the delay time of the anode current pulse and photon pulse (corresponding to the optical transitions) and the shape of the voltage collapse. The working conditions were: pressure p=10 -5 --10 -3 Torr, anode voltage U/sub a/=800 V, and maximum magnetic field B/sub max/=1200 Gs. Photoelectrical recording of spectral lines was performed with a monochromator in the wavelength range 3600--6000 A, and the total optical spectrum was recorded simultaneously on a photoplate in a separate spectrograph in the wavelength range 2000--10 000 A. The delay time of the anode current pulse and photon pulse are approximately the same and are in the millisecond range. The delay time of the photon pulse does not depend on the wavelength. Simultaneously the spectral lines of the working gas (A II), residual gas (O II), and tungsten (W I) appear. Tungsten atoms appear at the moment of breakdown as a result of ion bombardment of the cathode. Neutral atomic lines of the working gas (A I) have not been observed. Radial analysis shows that the delay time of the photon pulse does not depend on the radius. Spectroscopic results have been analyzed in terms of excitation and ionization processes during the formation time. The shape of the voltage collapse suggests the streamer breakdown mechanism

  15. Field measurements of the ambient ozone formation potential in Beijing during winter

    Science.gov (United States)

    Crilley, Leigh; Kramer, Louisa; Thomson, Steven; Lee, James; Squires, Freya; Bloss, William

    2017-04-01

    The air quality issues in Beijing have been well-documented, and the severe air pollution levels result in a unique chemical mix in the urban boundary layer, both in terms of concentration and composition. As many of the atmospheric chemical process are non-linear and interlinked, this makes predictions difficult for species formed in atmosphere, such as ozone, requiring field measurements to understand these processes in order to guide mitigation efforts. To investigate the ozone formation potential of ambient air, we employed a custom built instrument to measure in near real time the potential for in situ ozone production, using an artificial light source. Our results are thus indicative of the ozone formation potential for the sampled ambient air mixture. Measurements were performed as part of the Air Pollution and Human Health (APHH) field campaign in November / December 2016 at a suburban site in central Beijing. We also conducted experiments to examine the ozone production sensitivity to NOx. We will present preliminarily results from ambient sampling and NOx experiments demonstrating changes in the ozone production potential during clean and haze periods in Beijing.

  16. Wormholes propagation for fractured-vuggy formation: Laboratory tests, numerical simulation and field application

    Directory of Open Access Journals (Sweden)

    Fei Liu

    2017-12-01

    Full Text Available The propagation of wormhole is vital important for matrix acidizing and acid fracturing in carbonate reservoirs. While the formation of acid dissolved wormhole is derived from heterogeneous physical and chemical transportations and reactions. Alveolate dissolved pores, krast caves, and natural fissures are the major reservoir spaces for the Sinian dolomite formation in the Anyue gas field of the Sichuan Basin. There were four categories of formation, which are matrix dominated, inter-breccia dissolved pore dominated, dissolved pore and cave dominated, and fissure and cave dominated, based on the development intensity and connectedness of caves and fissures. The caves and fissures make the wormhole formation and propagation particularly complicated. Firstly, the 3-D topological structure of dissolved pores, vugs, fissures and throats inside cores is quantitatively scanned by CT imaging technology for its feature of vivid and damage-free. Secondly, 3-D patterns of wormhole are obtained with CT scanning after core flooding by acid. Additionally, the pore-throat network model is reconstructed with digital cores technology. Then, the size and ratio of pore and throat before and after core flooding by acid is analyzed and the absolute permeability of pore scale flow is numerically simulated to understand the fundamental influence of pores and vugs distribution and connectedness on wormhole propagation. Lastly, the wormhole pattern gained by CT scanning and simulating with two-scale model is compared. Meanwhile, the corrected two-scale model is utilized to simulate the wormhole propagation for matrix acidizing and acid fracturing of Sinian fractured-vuggy dolomite in Anyue gas field, Sichuan Basin. The optimized injection rate and volume were in agreement with the characteristic matrix acidizing operating curve, which indicates that the two-scale model was suitable for matrix acidizing optimization design of such formations. In addition, the simulated

  17. Palaeo-ecological and archaeological analysis of two Dutch Celtic fields (Zeijen-Noordse Veld and Wekerom-Lunteren): solving the puzzle of local Celtic field bank formation

    NARCIS (Netherlands)

    Arnoldussen, Stijn; Linden, Marjolein van der

    2017-01-01

    Celtic fields are the best preserved and most widely distributed type of prehistoric agricultural landscape in the Netherlands, and occur throughout northwestern Europe. In this contribution, data from two excavated Dutch Celtic fields are used to explain the process of bank formation and to unravel

  18. Formation of Field Reversed Configuration (FRC on the Yingguang-I device

    Directory of Open Access Journals (Sweden)

    Qizhi Sun

    2017-09-01

    Full Text Available As a hybrid approach to realizing fusion energy, Magnetized Target Fusion (MTF based on the Field Reversed Configuration (FRC, which has the plasma density and confinement time in the range between magnetic and inertial confinement fusion, has been recently widely pursued around the world. To investigate the formation and confinement of the FRC plasma injector for MTF, the Yingguang-I, which is an FRC test device and contains a multi-bank program-discharged pulsed power sub-system, was constructed at the Institute of Fluid Physics (IFP, China. This paper presents the pulsed power components and their parameters of the device in detail, then gives a brief description of progress in experiments of FRC formation. Experimental results of the pulsed power sub-system show that the peak current/magnetic field of 110 kA/0.3 T, 10 kA/1.2 T and 1.7 MA/3.4 T were achieved in the bias, mirror and θ-pinch circuits with quarter cycle of 80 μs, 700 μs and 3.8 μs respectively. The induced electric field in the neutral gas was greater than 0.25 kV/cm when the ionization bank was charged to 70 kV. With H2 gas of 8 Pa, the plasma target of density 1016 cm−3, separatrix radius 4 cm, half-length 17 cm, equilibrium temperature 200 eV and lifetime 3 μs (approximately the half pulse width of the reversed field have been obtained through the θ-pinch method when the bias, mirror, ionization and θ-pinch banks were charged to 5 kV, 5 kV, 55 kV and ±45 kV respectively. The images from the high-speed end-on framing camera demonstrate the formation processes of FRC and some features agree well with the results with the two-dimension magneto hydrodynamics code (2D-MHD.

  19. Linking lipid architecture to bilayer structure and mechanics using self-consistent field modelling

    NARCIS (Netherlands)

    Pera, H.; Kleijn, J.M.; Leermakers, F.A.M.

    2014-01-01

    To understand how lipid architecture determines the lipid bilayer structure and its mechanics, we implement a molecularly detailed model that uses the self-consistent field theory. This numerical model accurately predicts parameters such as Helfrichs mean and Gaussian bending modulus k c and k ¯ and

  20. The origin of the young stellar population in the solar neighborhood -- A link to the formation of the Local Bubble?

    Science.gov (United States)

    Berghöfer, T. W.; Breitschwerdt, D.

    2002-07-01

    We have analyzed the trajectories of moving stellar groups in the solar neighborhood in an attempt to estimate the number of supernova explosions in our local environment during the past 20 million years. Using Hipparcos stellar distances and the results of kinematical analyses by Asiain et al. (\\cite{Asiain1999a}a) on the Pleiades moving groups, we are able to show that subgroup B1, consisting of early type B stars up to 10 Msun, but lacking more massive objects, has passed through the local interstellar medium within less than 100 pc. Comparing the stellar content of B1 with the initial mass function derived from the analysis of galactic OB associations, we estimate the number of supernova explosions and find that about 20 supernovae must have occurred during the past ~ 10 - 20 million years, which is suggested to be the age of the Local Bubble; the age of the star cluster is about ~ 20 - 30 million years. For the first time, this provides strong evidence that the Local Bubble must have been created and shaped by multi-supernova explosions and presumably been reheated more than 1 million years ago, consistent with recent findings of an excess of 60Fe in a deep ocean ferromanganese crust. Calculating similarity solutions of an expanding superbubble for time-dependent energy input, we show that the number of explosions is sufficient to explain the size of the Local Bubble. The present energy input rate is about dot ESN ~ 5 x 1036 erg/s, in good agreement with the estimated local soft X-ray photon output rate. It seems plausible that the origin of the Local Bubble is also linked to the formation of the Gould Belt, which originated about 30-60 Myrs ago.

  1. Cyclic architecture of a carbonate sequence, early Aptian Shuaiba formation, Al Huwaisah field, Oman

    Energy Technology Data Exchange (ETDEWEB)

    Groetsch, J. (Shell Research, Rijswijk (Netherlands))

    1993-09-01

    Sequence stratigraphy of carbonates is a topic of ongoing controversy. In particular, small-scale shallowing-upward cycles can provide some key information needed for interpretation of carbonate sequences and/or third-order sea level changes. The early Aptian Shuaiba Formation in the Al Huwaisah field consists of about 90 m of shallow-water limestones. Throughout the formation, an overall decreasing influx of fine detritus is notable toward the top. The sequence can be subdivided into a basal unit and an overlying unit. Both units are composed of meter-scale shallowing-upward cycles of different composition, which can be recognized in core and well logs. Fourier analysis of the first principle component of a set of well logs (GR, FDC, CNL, Sonic) revealed an abrupt change in spectral behavior between the two units. Toward the top, the spectra are [open quotes]cleaning upward[close quotes] with an increasing pronunciation of a peak grouping of 1: 2: 5, suggesting a better preservation of orbital variations in the upper unit. Preservation of orbital forcing in shallowing-upward cycles requires rapid rates of sedimentation. In addition, increased shallow-water carbonate production on the platform is indicated by the appearance of reefal organisms. Hence, a higher rate of sedimentation and therefore a faster aggradation of the platform is inferred for the upper unit, which could have resulted from an increased rate of relative sea level rise. The sudden facies differentiation on the broad Arabian shelf in the upper part of the early Aptian reflects the development of an intrashelf basin. Changes in rate of relative sea level rise on the Arabian shelf might explain the repeated alternation from an easily correlatable ramp-type sedimentation, with slightly higher input of fine terrigenous sediment (e.g., lower unit of Shuaiba Formation) and a differentiation into platform and intrashelf basin facies due to faster aggradation (e.g., upper unit of Shuaiba Formation).

  2. Formation of excited neutral D* fragments from D2 by a strong laser field

    Science.gov (United States)

    Berry, Ben; Zohrabi, M.; Jochim, Bethany; Severt, T.; Ablikim, U.; Hayes, D.; Rajput, Jyoti; Kanaka Raju, P.; Feizollah, Peyman; Carnes, K. D.; Esry, B. D.; Ben-Itzhak, I.

    2015-05-01

    Excited neutral D* fragments from D2 are produced by intense, ultra-short laser pulses (5-85 fs). The kinetic energy release (KER) upon fragmentation is found to be very sensitive to laser parameters such as chirp, peak intensity, and pulse duration. Furthermore, using field ionization of highly excited D* fragments, we are able to determine the n population in a range of excited states (17 process in order to link the measured population to that created by the laser. On the technical side, we also present a scheme for determining the detection efficiency of an MCP detector for excited neutral atoms. This work was supported by the Chemical Sciences, Geosciences, and Biosciences Division, Office of Basic Energy Sciences, Office of Science, U.S. Department of Energy. BJ is also supported by DOE-SCGF (DE-AC05-06OR23100).

  3. An objective measure for the sensitivity of room impulse response and its link to a diffuse sound field

    DEFF Research Database (Denmark)

    Prislan, Rok; Brunskog, Jonas; Jacobsen, Finn

    2014-01-01

    This study is relevant to acoustic measurements in reverberation rooms such as measurements of sound transmission, sound absorption, and sound power levels of noise sources. The study presents a quantitative measure for the diffuseness in a room, which is first introduced theoretically and sub......- sequently examined experimentally. The sensitivity of a room due to changes in the initial condi- tions is quantified by measuring a pair of impulse responses in a room differing only in the sound source position. Such changes are linked to mixing and the diffuse sound field. The measure is based...

  4. Chemical evolution of formation waters in the Palm Valley gas field, Northern Territory

    International Nuclear Information System (INIS)

    Andrew, A.S.; Giblin, A.M.

    2000-01-01

    The chemical composition and evolution of formation waters associated with gas production in the Palm Valley field, Northern Territory, has important implications for reservoir management, saline water disposal, and gas reserve calculations. Historically, the occurrence of saline formation water in gas fields has been the subject of considerable debate. A better understanding of the origin, chemical evolution and movement of the formation water at Palm Valley has important implications for future reservoir management, disposal of highly saline water and accurate gas reserves estimation. Major and trace element abundance data suggest that a significant component of the highly saline water from Palm Valley has characteristics that may have been derived from a modified evaporated seawater source such as an evaporite horizon. The most dilute waters probably represent condensate and the variation in the chemistry of the intermediate waters suggests they were derived from a mixture of the condensate with the highly saline brine. The chemical and isotopic results raise several interrelated questions; the ultimate source of the high salinity and the distribution of apparently mixed compositions. In this context several key observation are highlighted. Strontium concentrations are extremely high in the brines; although broadly similar in their chemistry, the saline fluids are neither homogeneous nor well mixed; the 87 Sr/ 86 Sr ratios in the brines are higher than the signatures preserved in the evaporitic Bitter Springs Formation, and all other conceivably marine-related evaporites (Strauss, 1993); the 87 Sr/ 86 Sr ratios in the brines are lower than those measured from groundmass carbonates in the host rocks, and that the 87 Sr/ 86 Sr ratios of the brines are similar, but still somewhat higher than those measured in vein carbonates from the reservoir. It is concluded that the high salinity brine entered the reservoir during the Devonian uplift and was subsequently

  5. Using sediment transport and river restoration to link research and education, and promote K-12 female involvement in STEM fields

    Science.gov (United States)

    Yager, E. M.; Bradley-Eitel, K.

    2011-12-01

    The focus of this CAREER award is to better understand and predict the mechanics of sediment transport, to link research and education through courses and shared field sites, and to increase female interest in STEM fields. To accomplish the education component of this proposal we have focused on the following three activities: 1) a Keystone course on the scientific method, 2) a Women Outside with Science (WOWS) camp and 3) a permanent field site for research and education on river processes. In the Keystone Course, students investigated the impact of roughness addition, in sediment-starved river reaches (e.g. downstream of dams), on the retention of gravel used for spawning. They developed research questions and hypotheses, designed and conducted a set of scaled laboratory flume experiments, analyzed their data and wrote a draft manuscript of their results. Student feedback was overwhelmingly positive on the merits of this course, which included hands-on learning of the following: basic sediment transport and fluvial geomorphology, applied statistics, laboratory methods, and scientific writing skills. Students sometimes struggled when flume experiments did not progress as planned, and in the analysis and interpretation of complex data. Some of the students in the course have reanalyzed data, conducted additional experiments and are currently rewriting the manuscript for submission to a peer-reviewed journal. Such a course fundamentally links research and teaching, and provides an introduction to research for advanced undergraduates or beginning graduate students. We have also run one summer WOWS camp, which was a ten day camping and inquiry based research experience for 20 female junior-high and high-school students. The girls studied climate change and water related issues, worked on a restoration project on the Little Salmon River, met with a fish biologist and did fish habitat surveys and studied water quality along the North Fork of the Payette River while on a

  6. Competence formation of engineering directions students in the field of energy saving as a way to create new generation technologies

    Science.gov (United States)

    Gilmanshin, I. R.; Gilmanshina, S. I.

    2017-09-01

    The urgency of the formation of competence in the field of energy saving in the process of studying engineering and technical disciplines at the university is substantiated. The author’s definition of the competence in the field of energy saving is given, allowing to consider the necessity of its formation among students - future engineers as a way to create technologies of a new generation. The essence of this competence is revealed. The system of work, pedagogical conditions and technologies of its formation in the conditions of the federal university is substantiated.

  7. Results of research and commercial production of shale oil in Bazhenov formation on Ai-Pimskoe field

    Science.gov (United States)

    Sarancha, A. V.; Shuldikova, N. S.; Mayer, A. V.; Sumin, A. N.

    2017-10-01

    A large number of articles devoted to Bazhenov Formation appeared in Russian scientific and technical journals, aimed at specialists in of oil and gas fields development over the last 5 – 10 years. This is due to the fact that traditional hydrocarbon resources are gradually reducing, making oil companies pay attention to shale oil; the largest deposits in the Russian Federation are in Bazhenov Formation. The main purpose of this article is to highlight results obtained during the development of Bazhenov Formation on Ai-Pimskoe field in Western Siberia.

  8. Toxicant interactions with food algae: a missing link between laboratory and field effects?

    Science.gov (United States)

    Podemski, C L; Culp, J M

    2001-01-01

    Algae fed to invertebrate subjects of chronic toxicity testing are cultured without exposure to test substances. This approach may reduce the ability of bioassays to predict field effects because it assumes that bioconcentration is the only important uptake route, and that an interaction between toxicant and algae does not occur or is not relevant to the effect of the toxicant on test animals. The research presented in this paper focuses on the effects of a bleached kraft mill effluent (BKME) on algae used as food for test animals and the possible consequences of this exposure to bioassay results. The experiment consisted of exposing cultures of a pennate diatom, Navicula, to a range (0-7%) of BKME concentrations for 15 days. Final biomass (measured as chlorophyll a and ash free dry mass) was significantly greater in cultures exposed to 5% and 7% BKME. The carbon-to-nitrogen ratio was significantly higher in diatom cultures exposed to 7% BKME, and total lipid content ranged from 11.7% in the control to 15.8% in the 7% treatment. BKME exposure also increased bacterial content and altered the elemental composition (particularly strontium, barium, iron, and cobalt) of Navicula relative to control cultures. Because changes in food abundance and food quality (e.g., dietary lipids, carbohydrates, proteins) are known to modify toxicity and because contaminant uptake can occur through ingestion, exposing algal food supplies to toxicants would allow chronic bioassays to better simulate field conditions. This approach would be of value in situations where bioassays are intended to predict field effects rather than to compare the toxic potential of effluent samples. Although culturing food algae under exposure to contaminants poses methodological challenges, this approach may serve to enhance the predictive ability of chronic bioassays.

  9. Links between the charge model and bonded parameter force constants in biomolecular force fields

    Science.gov (United States)

    Cerutti, David S.; Debiec, Karl T.; Case, David A.; Chong, Lillian T.

    2017-10-01

    The ff15ipq protein force field is a fixed charge model built by automated tools based on the two charge sets of the implicitly polarized charge method: one set (appropriate for vacuum) for deriving bonded parameters and the other (appropriate for aqueous solution) for running simulations. The duality is intended to treat water-induced electronic polarization with an understanding that fitting data for bonded parameters will come from quantum mechanical calculations in the gas phase. In this study, we compare ff15ipq to two alternatives produced with the same fitting software and a further expanded data set but following more conventional methods for tailoring bonded parameters (harmonic angle terms and torsion potentials) to the charge model. First, ff15ipq-Qsolv derives bonded parameters in the context of the ff15ipq solution phase charge set. Second, ff15ipq-Vac takes ff15ipq's bonded parameters and runs simulations with the vacuum phase charge set used to derive those parameters. The IPolQ charge model and associated protocol for deriving bonded parameters are shown to be an incremental improvement over protocols that do not account for the material phases of each source of their fitting data. Both force fields incorporating the polarized charge set depict stable globular proteins and have varying degrees of success modeling the metastability of short (5-19 residues) peptides. In this particular case, ff15ipq-Qsolv increases stability in a number of α -helices, correctly obtaining 70% helical character in the K19 system at 275 K and showing appropriately diminishing content up to 325 K, but overestimating the helical fraction of AAQAA3 by 50% or more, forming long-lived α -helices in simulations of a β -hairpin, and increasing the likelihood that the disordered p53 N-terminal peptide will also form a helix. This may indicate a systematic bias imparted by the ff15ipq-Qsolv parameter development strategy, which has the hallmarks of strategies used to develop

  10. Border to Beltway: A Formative Field Exchange Program between Two Community Colleges for Non-Traditional Students

    Science.gov (United States)

    Villalobos, J. I.; Bentley, C.

    2014-12-01

    Community College students account for over 40% of all undergraduates in the US as well as the majority of minority students attending undergraduate courses. With issues in the geosciences such as; being the least diverse of all major STEM fields, an increasing number of retiring geoscientists, and a projected geoscience job growth not matching the number of geoscience graduates, the geoscience community needs to look at community colleges as a solution to these issues. A key factor for students entering and excelling in the geoscience is the opportunity for formative undergraduate field experiences. Formative field experiences go beyond one-day field excursions by incorporating field projects, interactive learning, and community building between participants in regions students are unfamiliar with. Unfortunately, these types of formative experiences often require logistics and resources that are not available or known to community college faculty. In order to build a framework for implementing formative field experiences by community colleges a two-week "field exchange" between two community colleges with different geological, social, and cultural settings was conducted. Supported with a supplemental grant from NSF, the "Border to Beltway" program provided 11 students from El Paso Community College and another 13 from Northern Virginia Community College with two one-week regional geology field trips: First, to West Texas in March 2014, and second, to the mid-Atlantic region in May 2014. Students were selected based on academic standing, non-traditional (minority, female, over 35, veteran) status, and interest in geology. Qualitative data collected from participants regarding the implementation of the field exchange include; student perception of geology before and after exchange, challenges students faced in the field or traveling for the first time, quantity and quality of projects given, and working with others from different backgrounds. Data regarding planning

  11. Field-Reversed Configuration Formation Scheme Utilizing a Spheromak and Solenoid Induction

    International Nuclear Information System (INIS)

    Gerhardt, S.P.; Belova, E.V.; Yamada, M.; Ji, H.; Ren, Y.; McGeehan, B.; Inomoto, M.

    2008-01-01

    A new field-reversed configuration (FRC) formation technique is described, where a spheromak transitions to a FRC with inductive current drive. The transition is accomplished only in argon and krypton plasmas, where low-n kink modes are suppressed; spheromaks with a lighter majority species, such as neon and helium, either display a terminal tilt-mode, or an n=2 kink instability, both resulting in discharge termination. The stability of argon and krypton plasmas through the transition is attributed to the rapid magnetic diffusion of the currents that drive the kink-instability. The decay of helicity during the transition is consistent with that expected from resistivity. This observation indicates a new scheme to form a FRC plasma, provided stability to low-n modes is maintained, as well as a unique situation where the FRC is a preferred state

  12. Field-Reversed Configuration Formation Scheme Utilizing a Spheromak and Solenoid Induction

    Energy Technology Data Exchange (ETDEWEB)

    Gerhardt, S. P.; Belova, E. V.; Yamada, M.; Ji, H.; Ren, B.; McGeehan, B.; Inomoto, M.

    2008-06-12

    A new field-reversed configuration (FRC) formation technique is described, where a spheromak transitions to a FRC with inductive current drive. The transition is accomplished only in argon and krypton plasmas, where low-n kink modes are suppressed; spheromaks with a lighter majority species, such as neon and helium, either display a terminal tilt-mode, or an n=2 kink instability, both resulting in discharge termination. The stability of argon and krypton plasmas through the transition is attributed to the rapid magnetic diffusion of the currents that drive the kink-instability. The decay of helicity during the transition is consistent with that expected from resistivity. This observation indicates a new scheme to form a FRC plasma, provided stability to low-n modes is maintained, as well as a unique situation where the FRC is a preferred state.

  13. FIELD DEMONSTRATION OF CARBON DIOXIDE MISCIBLE FLOODING IN THE LANSING-KANSAS CITY FORMATION, CENTRAL KANSAS

    Energy Technology Data Exchange (ETDEWEB)

    Alan Byrnes; G. Paul Willhite; Don Green; Martin Dubois; Richard Pancake; Timothy Carr; W. Lynn Watney; John Doveton; Willard Guy; Rodney Reynolds; Dave Murfin; James Daniels; Russell Martin; William Flanders; Dave Vander Griend; Eric Mork; Paul Cantrell

    2004-06-30

    A pilot carbon dioxide miscible flood was initiated in the Lansing Kansas City C formation in the Hall Gurney Field, Russell County, Kansas. Continuous carbon dioxide injection began on December 2, 2003. By the end of June 2004, 6.26 MM lb of carbon dioxide were injected into the pilot area. Carbon dioxide injection rates averaged about 250 MCFD. Carbon dioxide was detected in one production well near the end of May. The amount of carbon dioxide produced was small during this period. Wells in the pilot area produced 100% water at the beginning of the flood. Oil production began in February, increasing to an average of about 2.5 B/D in May and June. Operational problems encountered during the initial stages of the flood were identified and resolved.

  14. Theoretical studies on models of lysine-arginine cross-links derived from α-oxoaldehydes: a new mechanism for glucosepane formation.

    Science.gov (United States)

    Nasiri, Rasoul; Zahedi, Mansour; Jamet, Hélène; Moosavi-Movahedi, Ali Akbar

    2012-04-01

    Availability and high reactivity of α-oxoaldehydes have been approved by experimental techniques not only in vivo systems but also in foodstuffs. In this article we re-examine the mechanism of glucosepane formation by using computational model chemistry. Density functional theory has been applied to propose a new mechanism for glucosepane formation through reaction of α-oxoaldehydes with methyl amine (MA) and methyl guanidine (MGU) models of lysine and arginine residues respectively. This non enzymatic process can be described in three main steps: (1) Schiff base formation from methyl amine, methyl glyoxal (MGO) (2) addition of methyl guanidine and (3) addition of glyceraldehyde. We show that this process is thermodynamically possible and presents a rate-determining step with a reasonable free energy barrier equal to 37.8 kcal mol(-1) in water solvent. Comparisons were done with the mechanism formation of GODIC (glyoxal-derived imidazolium cross-link) and MODIC (methyl glyoxal-derived imidazolium cross-link), two other important cross-links in vivo.

  15. Making longevity in an aging society: linking Medicare policy and the new ethical field.

    Science.gov (United States)

    Kaufman, Sharon R

    2010-01-01

    Life-extending interventions for older persons are changing medical knowledge and societal expectations about longevity. Today's consciousness about growing older is partly shaped by a new form of ethics, constituted by and enabled through the routines and institutions that comprise ordinary clinical care. Unlike bioethics, whose emphasis is on clinical decision-making in individual situations, this new form of ethics is exceptionally diffuse and can be characterized as an ethical field. It is located in and shaped by health-care policies, standard technologies, and clinical evidence, and it emerges in what patients and families come to need and want. Three developments illustrate this ethical field at work: the changing nature of disease, especially the ascent of risk awareness and risk-based strategies for life extension; the role of technology in reshaping the ends of medicine; and the role of Medicare policy in creating need and ethical necessity. Medicare's expanding criteria for payment coverage of liver transplantation and implantable cardiac devices illustrate the pervasive logic of this new form of ethics. The powerful connection between the technological imperative and its ethical necessity is rarely mentioned in Medicare reform debates.

  16. The Physical Rehabilitation: a therapeutically field that links the Faculty of Physical Culture with the community

    Directory of Open Access Journals (Sweden)

    Deisy Milhet Cruz

    2017-04-01

    Full Text Available The research project stands for a new glance to the integration school-community, this one is aimed at providing the theoretical-practical contents to the rehabilitation of individuals in the territory called Capitán San Luis based on a therapeutically field, it also contributes to the academic process in the faculty by facilitating the unit theory-practice. On behalf of the subjects comprising the discipline physical Culture and prophylactic taught by the members of the project. In this field are duly attended students, professors of the faculty, also members of the community nearby, by using equipment and means showed and validated in some scientific events. In brief this rehabilitation resource improves the quality of life of everyone who undergoes any of the treatments put into practice. Different methods were carried out just as observation, surveys and interviews. The expert criterion based on Delphi method, the pre experiment which means served for the diagnosis and the feasibility confirmation of the research.

  17. Radiogenic heat production in Rudeis Formation, Lower Miocene, Belayim marine oil field, Gulf of Suez, Egypt

    Science.gov (United States)

    Mohamed, Hassan; Mizunaga, Hideki; Abou Ashour, Nasser Mohamed; Elterb, Refaat Ahmed; Elalfy, Ibrahim Mostafa; Elsayed, Ayman Shebel

    2017-09-01

    This study describes radiogenic heat production (RHP) estimated from two sets of well logging data recorded in Rudeis Formation, Belayim marine oil field. Subsurface total count gamma-ray (GR) data were recorded in nine wells, seven of which possessed spectrometric data (eU, eTh, and K). The data show that RHP estimated from GR logs (ABR) varies from 0.13 to 1.73 µW/m3, with an average of 0.7 µW/m3 and a standard deviation of 0.26 µW/m3. In addition, 72.9% of RHP values fall within the range of 0.6-1.0 µW/m3. RHP estimated from the concentrations of radioactive elements (AR) vary from 0.13 to 2.1 µW/m3, with an average 0.71 µW/m3 and a standard deviation of 0.38 µW/m3. 50% of these RHP values fall within the range of 0.6-1.0 µW/m3. Cross-correlation of ABR and AR calculations yielded a moderate fit of 0.75. The three-dimensional (3D)-slicing of the reservoir shows that the northern and north-western parts of the study area have higher RHP compared to other parts. The estimated RHP can produce enough heat which has an effect on the hydrocarbon potential in Rudeis Formation.

  18. Formation of Negative Metal Ions in a Field-Free Plasma

    International Nuclear Information System (INIS)

    Larsson, E.

    1969-02-01

    A field-free and homogeneous plasma of a large volume is formed by neutron irradiation of 3 He at a density corresponding to NTP and at gas temperatures in the range 300-1600 deg K. The accuracy and ease by which the source density of free electrons can be varied and controlled offers special possibilities to study recombination and attachment phenomena in the absence of diffusion. These possibilities are described and utilized for the study of the effects of mixing the helium gas with metal vapours. Attachment of electrons to neutral metal atoms is found to be the dominant cause of electron removal for metal concentrations above certain limits. Negative metal ions are formed and the rate of their formation was determined to be about 10 -13 cm 3 /s. Evidence is also presented, that for such conditions where formation of negative metal ions does not occur, the electrons are lost in electron-ion recombinations, in which the third body is not an electron. No molecular helium spectrum is observed from the plasma when it is very close to spectroscopic purity. Instead, between 3,000-7,000 A only one atomic helium line at 5875 A is observed. The recombination of He + 2 may therefore be dissociative. A difference in recombination behaviour between 3 He and 4 He at high pressures may therefore exist considering results from previous work on 4 He

  19. Mean-field approach to evolving spatial networks, with an application to osteocyte network formation

    Science.gov (United States)

    Taylor-King, Jake P.; Basanta, David; Chapman, S. Jonathan; Porter, Mason A.

    2017-07-01

    We consider evolving networks in which each node can have various associated properties (a state) in addition to those that arise from network structure. For example, each node can have a spatial location and a velocity, or it can have some more abstract internal property that describes something like a social trait. Edges between nodes are created and destroyed, and new nodes enter the system. We introduce a "local state degree distribution" (LSDD) as the degree distribution at a particular point in state space. We then make a mean-field assumption and thereby derive an integro-partial differential equation that is satisfied by the LSDD. We perform numerical experiments and find good agreement between solutions of the integro-differential equation and the LSDD from stochastic simulations of the full model. To illustrate our theory, we apply it to a simple model for osteocyte network formation within bones, with a view to understanding changes that may take place during cancer. Our results suggest that increased rates of differentiation lead to higher densities of osteocytes, but with a smaller number of dendrites. To help provide biological context, we also include an introduction to osteocytes, the formation of osteocyte networks, and the role of osteocytes in bone metastasis.

  20. Plasmonic and Mie scattering control of far-field interference for regular ripple formation on various material substrates.

    Science.gov (United States)

    Obara, Go; Maeda, Naoki; Miyanishi, Tomoya; Terakawa, Mitsuhiro; Nedyalkov, Nikolay N; Obara, Minoru

    2011-09-26

    We present experimental and theoretical results on plasmonic control of far-field interference for regular ripple formation on semiconductor and metal. Experimental observation of interference ripple pattern on Si substrate originating from the gold nanosphere irradiated by femtosecond laser is presented. Gold nanosphere is found to be an origin for ripple formation. Arbitrary intensity ripple patterns are theoretically controllable by depositing desired plasmonic and Mie scattering far-field pattern generators. The plasmonic far-field generation is demonstrated not only by metallic nanostructures but also by the controlled surface structures such as ridge and trench structures on various material substrates. © 2011 Optical Society of America

  1. Magnetic field effect on Gd2(MoO4)3 domain structure formation in the phase transformation range

    International Nuclear Information System (INIS)

    Flerova, S.A.; Tsinman, I.L.

    1987-01-01

    The behaviour of ferroelastic-ferroelectric domain structure of gadolinium molybdate crystal (GMO)during its formation in the magnetic field in the vicinity of phase transformation is studied.It is shown that the formation of domain structure in the presence of a temperature gradient occurs in the field of mechanical stresses whose mainly stretching effect is concentrated near phase boundaries.The magnetic field intensifies summary mechanical stresses where a domain structure in a ferroelectric phase is formed due to interaction with the elements of inhomogeneous and differently oriented currents near phase boundaries

  2. Molecular typing of Leptospira spp. strains isolated from field mice confirms a link to human leptospirosis.

    Science.gov (United States)

    Li, S J; Wang, D M; Zhang, C C; Li, X W; Yang, H M; Tian, K C; Wei, X Y; Liu, Y; Tang, G P; Jiang, X G; Yan, J

    2013-11-01

    In recent years, human leptospirosis has been reported in Jinping and Liping counties, Guizhou province, but the leptospires have never been isolated. To track the source of infection and understand the aetiological characteristics, we performed surveillance for field mice carriage of leptospirosis in 2011. Four strains of leptospire were isolated from Apodemus agrarius. PCR confirmed the four isolates as pathogenic. Multiple-locus variable-number tandem repeat analysis (MLVA) showed that the four strains were closely related to serovar Lai strain 56601 belonging to serogroup Icterohaemorrhagiae, which is consistent with the antibody detection results from local patients. Furthermore, the diversity of leptospiral isolates from different hosts and regions was demonstrated with MLVA. Our results suggest that A. agrarius may be the main carrier of Leptospira in Jinping and Liping counties, and the serogroup Icterohaemorrhagiae serovar may be the epidemic serogroup of Leptospira. This will contribute to the control and prevention of leptospirosis in these localities.

  3. New evidence for "far-field" Holocene sea level oscillations and links to global climate records

    Science.gov (United States)

    Leonard, N. D.; Welsh, K. J.; Clark, T. R.; Feng, Y.-x.; Pandolfi, J. M.; Zhao, J.-x.

    2018-04-01

    Rising sea level in the coming century is of significant concern, yet predicting relative sea level change in response to eustatic sea level variability is complex. Potential analogues are provided by the recent geological past but, until recently, many sea level reconstructions have been limited to millennial scale interpretations due to age uncertainties and paucity in proxy derived records. Here we present a sea level history for the tectonically stable "far-field" Great Barrier Reef, Australia, derived from 94 high precision uranium-thorium dates of sub-fossil coral microatolls. Our results provide evidence for at least two periods of relative sea level instability during the Holocene. These sea level oscillations are broadly synchronous with Indo-Pacific negative sea surface temperature anomalies, rapid global cooling events and glacial advances. We propose that the pace and magnitude of these oscillations are suggestive of eustatic/thermosteric processes operating in conjunction with regional climatic controls.

  4. Replacive sulfide formation in anhydrite chimneys from the Pacmanus hydrothermal field, Papua New Guinea

    Science.gov (United States)

    Los, Catharina; Bach, Wolfgang; Plümper, Oliver

    2016-04-01

    Hydrothermal flow within the oceanic crust is an important process for the exchange of energy and mass between the lithosphere, hydrosphere and biosphere. Infiltrated seawater heats up and interacts with wall rock, causing mineral replacement reactions. These play a large role in the formation of ore deposits; at the discharge zone, a hot, acidic and metal-rich potential ore fluid exits the crust. It mixes with seawater and forms chimneys, built up of sulfate minerals such as anhydrite (CaSO4), which are subsequently replaced by sulfide minerals. Sulfide formation is related to fluid pathways, defined by cracks and pores in the sulfate chimney. Over time, these systems might develop into massive sulfide deposits. The big question is then: how is sulfate-sulfide replacement related to the evolution of rock porosity? To address this question, sulfide-bearing anhydrite chimneys from the Pacmanus hydrothermal field (Manus Basin, Papua New Guinea) were studied using X-ray tomography, EMPA, FIB-SEM and -TEM. The apparently massive anhydrite turns out highly porous on the micro scale, with sulfide minerals in anhydrite cleavage planes and along grain boundaries. The size of the sulfide grains relates to the pores they grew into, suggesting a tight coupling between dissolution (porosity generation) and growth of replacive minerals. Some of the sulfide grains are hollow and apparently used the dissolving anhydrite as a substrate to start growth in a pore. Another mode of sulfide development is aggregates of euhedral pyrite cores surrounded by colloform chalcopyrite. This occurrence implies that fluid pathways have remained open for some time to allow several stages of precipitation during fluid evolution. To start the replacement and to keep it going, porosity generation is crucial. Our samples show that dissolution of anhydrite occurred along pathways where fluid could enter, such as cleavage planes and grain boundaries. It appears that fluids ascending within the inner

  5. HTLV-1 Tax Induces Formation of the Active Macromolecular IKK Complex by Generating Lys63- and Met1-Linked Hybrid Polyubiquitin Chains.

    Directory of Open Access Journals (Sweden)

    Yuri Shibata

    2017-01-01

    Full Text Available The Tax protein of human T-cell leukemia virus type 1 (HTLV-1 is crucial for the development of adult T-cell leukemia (ATL, a highly malignant CD4+ T cell neoplasm. Among the multiple aberrant Tax-induced effects on cellular processes, persistent activation of transcription factor NF-κB, which is activated only transiently upon physiological stimulation, is essential for leukemogenesis. We and others have shown that Tax induces activation of the IκB kinase (IKK complex, which is a critical step in NF-κB activation, by generating Lys63-linked polyubiquitin chains. However, the molecular mechanism underlying Tax-induced IKK activation is controversial and not fully understood. Here, we demonstrate that Tax recruits linear (Met1-linked ubiquitin chain assembly complex (LUBAC to the IKK complex and that Tax fails to induce IKK activation in cells that lack LUBAC activity. Mass spectrometric analyses revealed that both Lys63-linked and Met1-linked polyubiquitin chains are associated with the IKK complex. Furthermore, treatment of the IKK-associated polyubiquitin chains with Met1-linked-chain-specific deubiquitinase (OTULIN resulted in the reduction of high molecular weight polyubiquitin chains and the generation of short Lys63-linked ubiquitin chains, indicating that Tax can induce the generation of Lys63- and Met1-linked hybrid polyubiquitin chains. We also demonstrate that Tax induces formation of the active macromolecular IKK complex and that the blocking of Tax-induced polyubiquitin chain synthesis inhibited formation of the macromolecular complex. Taken together, these results lead us to propose a novel model in which the hybrid-chain-dependent oligomerization of the IKK complex triggered by Tax leads to trans-autophosphorylation-mediated IKK activation.

  6. Linking Meander Initation to Instability in the Cross-Sectional Sediment Transport Field

    Science.gov (United States)

    Eaton, B. C.

    2005-12-01

    Recent theoretical and experimental work on reach-scale channel dynamics suggests that stream channel response to changes in the discharge or sediment supply regime produce adjustments that are consistent with the optimality criteria (or extremal hypotheses) proposed by rational regime modellers. However, a general form of the optimality criteria based on the maximization of system-scale flow resistance permits multiple channel responses to the same imposed change, and is thus inadequate for predicting channel response, absent additional information. The way forward is to identify the geomorphic processes that produce various possible channel responses, and to develop an understanding of the conditions under which these processes may or may not be effective. Using a simple analytic model relating local sediment transport capacity to variance in the transverse shear stress distribution I develop a physically based conceptual model of the initiation of meandering in straight, bedload dominated streams as a result of a feedback mechanism. This corresponds to a channel response that is dominated by changes the energy slope, which appears to be dominant in channels having relatively erodible banks and transporting their bed material load at conditions near the threshold for entrainment. The feedback maximizes the cross sectional shear stress variance and, in order to achieve stability, minimizes the energy slope at repeated locations along the channel. These locations develop into pools in a fully developed meandering channel; they represent attractor states wherein sediment continuity is satisfied using the least possible energy expenditure per unit length of channel. Between two successive pools, a stream occupies a metastable, higher energy state (corresponding to a riffle) that requires greater energy expenditure per unit length of channel to transport the same volume of sediment. The model links processes at the scale of a channel width to adjustments of the

  7. FORMATION OF STUDENTS’ FOREIGN LANGUAGE COMPETENCE IN THE INFORMATIONAL FIELD OF CROSS CULTURAL INTERACTION

    Directory of Open Access Journals (Sweden)

    Vitaly Vyacheslavovich Tomin

    2015-09-01

    Full Text Available Knowledge of foreign languages is becoming an integral feature of competitive persona-lity, ability to engage in cross-cultural communication and productive cross-cultural inte-raction, characterized by an adequate degree of tolerance and multi-ethnic competence, the ability for cross-cultural adaptation, critical thinking and creativity. However, the concept of foreign language competence has so far no clear, unambiguous definitions, thereby indicating the complexity and diversity of the phenomenon, which is an integrative, practice-oriented outcome of the wish and ability for intercultural communication. There have been mentioned a variety of requirements, conditions, principles, objectives, means and forms of foreign language competence forming, among which special attention is paid to non-traditional forms of practical training and information field in a cross-cultural interaction. There have been explained the feasibility of their application, which allows solving a complex of series of educational and teaching tasks more efficiently. There have been clarified the term «information field» in cross-cultural interaction, which is a cross-section of internally inherent in every individual «sections» of knowledge, skills, and experience, arising in certain given educational frameworks and forming a communication channel. The resultative indicators of the formation of foreign language competence and ways to improve its effectiveness are presented.

  8. Effect of magnetic fields on green color formation in frog skin

    Science.gov (United States)

    Kashiwagi, H.; Kashiwagi, A.; Iwasaka, M.

    2017-05-01

    The present work is focused on a dynamic and efficient optical control system that is made possible by investigation of the body surfaces of various animals. Specifically, we expect Japanese tree frog (Hyla japonica) skin to provide a model for a flexible display device actuator mechanism. Tree frogs change body color from their original green to other colors in response to background colors. The color formation is controlled not only by chromatophores, but also by guanine microcrystals in iridophores. We collected sample microcrystals from the frog's dorsal skin and made a model display sheet using the green skin layers. The transparent chamber that contained the crystal suspension was layered to enhance light reflection. Sheet color was observed while the angle of light incidence was varied, with and without magnetic field exposure at 0.3 T. A slight increase in red and green intensity was detected. Additionally, reflected intensity increased with increasing angle of incidence. These results indicate that the guanine crystal platelets in frog skin can efficiently switch the reflected light direction under application of a magnetic field. This in turn suggests that a several-micron-sized microcrystal of this type is a candidate material for development of flexible optical chips for ambient light control.

  9. Effect of magnetic fields on green color formation in frog skin

    Directory of Open Access Journals (Sweden)

    H. Kashiwagi

    2017-05-01

    Full Text Available The present work is focused on a dynamic and efficient optical control system that is made possible by investigation of the body surfaces of various animals. Specifically, we expect Japanese tree frog (Hyla japonica skin to provide a model for a flexible display device actuator mechanism. Tree frogs change body color from their original green to other colors in response to background colors. The color formation is controlled not only by chromatophores, but also by guanine microcrystals in iridophores. We collected sample microcrystals from the frog’s dorsal skin and made a model display sheet using the green skin layers. The transparent chamber that contained the crystal suspension was layered to enhance light reflection. Sheet color was observed while the angle of light incidence was varied, with and without magnetic field exposure at 0.3 T. A slight increase in red and green intensity was detected. Additionally, reflected intensity increased with increasing angle of incidence. These results indicate that the guanine crystal platelets in frog skin can efficiently switch the reflected light direction under application of a magnetic field. This in turn suggests that a several-micron-sized microcrystal of this type is a candidate material for development of flexible optical chips for ambient light control.

  10. Star Formation, Quenching And Chemical Enrichment In Local Galaxies From Integral Field Spectroscopy

    Science.gov (United States)

    Belfiore, Francesco

    2017-08-01

    Within the currently well-established ΛCDM cosmological framework we still lack a satisfactory understanding of the processes that trigger, regulate and eventually quench star formation on galactic scales. Gas flows (including inflows from the cosmic web and supernovae-driven outflows) are considered to act as self-regulatory mechanisms, generating the scaling relations between stellar mass, star formation rate and metallicity observed in the local Universe by large spectroscopic surveys. These surveys, however, have so far been limited by the availability of only one spectrum per galaxy. The aim of this dissertation is to expand the study of star formation and chemical abundances to resolved scales within galaxies by using integral field spectroscopy (IFS) data, mostly from the ongoing SDSS-IV MaNGA survey. In the first part of this thesis I demonstrate the ubiquitous presence of extended low ionisation emission-line regions (LIERs) in both late- and early-type galaxies. By studying the Hα equivalent width and diagnostic line ratios radial profiles, together with tracers of the underlying stellar population, I show that LIERs are not due to a central point source but to hot evolved (post-asymptotic giant branch) stars. In light of this, I suggest a new classification scheme for galaxies based on their line emission. By analysing the colours, star formation rates, morphologies, gas and stellar kinematics and environmental properties of galaxies with substantial LIER emission, I identify two distinct populations. Galaxies where the central regions are LIER-like, but show star formation at larger radii are late types in which star formation is slowly quenched inside-out. This transformation is associated with massive bulges. Galaxies dominated by LIER emission at all radii, on the other hand, are red-sequence galaxies harbouring a residual cold gas component, acquired mostly via external accretion. Quiescent galaxies devoid of line emission reside in denser

  11. Water isotopic characterization of hypersaline formation of a petroleum field Reconcavo basin, Brazil

    International Nuclear Information System (INIS)

    Teles, Danilo Ribeiro de Sa; Azevedo, Antonio Expedito Gomes de

    2010-01-01

    Formation water is the water present in reservoir rock pores, produced together with petroleum. Usually it is hyper saline with concentrations that can be higher than 250 g/l of dissolved solids. The concentration of the dissolved elements and the isotopic composition of the water and of some of the dissolved elements can be excellent tracers to study the dynamic of underground fluid flux, the mixing of distinct sources and the origin of salinization of these waters. This work reports the isotopic composition (δ 2 H , δ 18 O) and electrical conductivity (EC) of formation waters from 10 wells of a petroleum field of the Reconcavo Basin, looking for their evolution, interaction with the minerals and rocks and reservoir interconnection. The samples have electric conductivity ranging from 84 to 137 mS/cm, with conductivity increasing with depth of production zone. It is observed an enrichment of deuterium and oxygen-18 with the depth of production zone, probably due to water-rock interactions that were probably increased by higher temperatures of the deeper levels and longer residence times. The samples from the production zone between 1450 to 1520 m, drained by 7 of the 10 wells sampled, show a small range in isotopic composition and in electric conductivity, indicating homogeneity in this level of the reservoir. In the shallow level of 450 m the values of δ 2 H , δ 18 O and EC are lower, with isotopic composition similar to the oceanic water, possibly representing the original water that entered the reservoir during the sedimentation of the basin. (author)

  12. Circumnuclear star formation in Mrk 42 mapped with Gemini Near-infrared Integral Field Spectrograph

    Science.gov (United States)

    Hennig, Moiré G.; Riffel, Rogemar A.; Dors, O. L.; Riffel, Rogerio; Storchi-Bergmann, Thaisa; Colina, Luis

    2018-03-01

    We present Gemini Near-infrared Integral Field Spectrograph (NIFS) observations of the inner 1.5 × 1.5 kpc2 of the narrow-line Seyfert 1 galaxy Mrk 42 at a spatial resolution of 60 pc and spectral resolution of 40 km s^{-1}. The emission-line flux and equivalent width maps clearly show a ring of circumnuclear star formation regions (CNSFRs) surrounding the nucleus with radius of ˜ 500 pc. The spectra of some of these regions show molecular absorption features which are probably of CN, TiO or VO, indicating the presence of massive evolved stars in the thermally pulsing asymptotic giant branch (TP-AGB) phase. The gas kinematics of the ring is dominated by rotation in the plane of the galaxy, following the large scale disk geometry, while at the nucleus an additional outflowing component is detected blueshifted by 300-500 km s^{-1}, relative to the systemic velocity of the galaxy. Based on the equivalent width of Brγ we find evidences of gradients in the age of H II regions along the ring of Mrk 42, favoring the pearls on a string scenario of star formation. The broad component of Paβ emission line presents a Full Width at Half Maximum (FWHM) of ˜ 1480 km s^{-1}, implying in a mass of ˜ 2.5 × 106 M⊙ for the central supermassive black hole. Based on emission-line ratios we conclude that besides the active galactic nucleus, Mrk 42 presents nuclear Starburst activity.

  13. ENVIRONMENTAL EFFECTS ON STAR FORMATION ACTIVITY AT z {approx} 0.9 IN THE COSMOS FIELD

    Energy Technology Data Exchange (ETDEWEB)

    Kajisawa, M.; Shioya, Y.; Taniguchi, Y.; Nagao, T.; Matsubayashi, K.; Riguccini, L. [Research Center for Space and Cosmic Evolution, Ehime University, Bunkyo-cho, Matsuyama 790-8577 (Japan); Aida, Y.; Ideue, Y. [Graduate School of Science and Engineering, Ehime University, Bunkyo-cho, Matsuyama 790-8577 (Japan); Murayama, T., E-mail: kajisawa@cosmos.phys.sci.ehime-u.ac.jp [Astronomical Institute, Graduate School of Science, Tohoku University, Aramaki, Aoba, Sendai 980-8578 (Japan)

    2013-05-01

    We investigated the fraction of [O II] emitters in galaxies at z {approx} 0.9 as a function of the local galaxy density in the Hubble Space Telescope (HST) COSMOS 2 deg{sup 2} field. [O II] emitters are selected by the narrowband excess technique with the NB711-band imaging data taken with Suprime-Cam on the Subaru telescope. We carefully selected 614 photo-z-selected galaxies with M{sub U3500} < -19.31 at z = 0.901 - 0.920, which includes 195 [O II] emitters, to directly compare the results with our previous study at z {approx} 1.2. We found that the fraction is almost constant at 0.3 Mpc{sup -2} < {Sigma}{sub 10th} < 10 Mpc{sup -2}. We also checked the fraction of galaxies with blue rest-frame colors of NUV - R < 2 in our photo-z-selected sample, and found that the fraction of blue galaxies does not significantly depend on the local density. On the other hand, the semi-analytic model of galaxy formation predicted that the fraction of star-forming galaxies at z {approx} 0.9 decreases with increasing projected galaxy density even if the effects of the projection and the photo-z error in our analysis were taken into account. The fraction of [O II] emitters decreases from {approx}60% at z {approx} 1.2 to {approx}30% at z {approx} 0.9 independent of galaxy environment. The decrease of the [O II] emitter fraction could be explained mainly by the rapid decrease of star formation activity in the universe from z {approx} 1.2 to z {approx} 0.9.

  14. Chlorhexidine Digluconate Effects on Planktonic Growth and Biofilm Formation in Some Field Isolates of Animal Bacterial Pathogens

    Science.gov (United States)

    Ebrahimi, Azizollah; Hemati, Majid; Habibian Dehkordi, Saeed; Bahadoran, Shahab; Khoshnood, Sheida; Khubani, Shahin; Dokht Faraj, Mahdi; Hakimi Alni, Reza

    2014-01-01

    Background: To study chlorhexidine digluconate disinfectant effects on planktonic growth and biofilm formation in some bacterial field isolates from animals. Objectives: The current study investigated chlorhexidine digluconate effects on planktonic growth and biofilm formation in some field isolates of veterinary bacterial pathogens. Materials and Methods: Forty clinical isolates of Escherichia coli, Salmonella serotypes, Staphylococcus. aureus and Streptococcus agalactiae (10 isolates for each) were examined for chlorhexidine digluconate effects on biofilm formation and planktonic growth using microtiter plates. In all of the examined strains in the presence of chlorhexidine digluconate, biofilm development and planktonic growth were affected at the same concentrations of the disinfectant. Results: Chlorhexidine digluconate inhibited the planktonic growth of different bacterial species at sub-MICs. But they were able to induce biofilm development of the E. coli, Salmonella spp., S. aureus and Str. agalactiae strains. Conclusions: Bacterial resistance against chlorhexidine is increasing. Sub-MIC doses of chlorhexidine digluconate can stimulate the formation of biofilm strains. PMID:24872940

  15. An objective measure for the sensitivity of room impulse response and its link to a diffuse sound field.

    Science.gov (United States)

    Prislan, Rok; Brunskog, Jonas; Jacobsen, Finn; Jeong, Cheol-Ho

    2014-10-01

    This study is relevant to acoustic measurements in reverberation rooms such as measurements of sound transmission, sound absorption, and sound power levels of noise sources. The study presents a quantitative measure for the diffuseness in a room, which is first introduced theoretically and subsequently examined experimentally. The sensitivity of a room due to changes in the initial conditions is quantified by measuring a pair of impulse responses in a room differing only in the sound source position. Such changes are linked to mixing and the diffuse sound field. The measure is based on the maximum of the absolute value of the cross-correlation between the time windowed sections of the two impulse responses. By integrating this quantity normalized by the energy of the impulse response of the room, a single number rating is obtained. Results based on three sets of experiments indicate that the diffusers and absorbers in the room influence the proposed sensitivity measures systematically.

  16. Prediction and comparison of down-link electric field and uplink localised SAR values for realistic indoor wireless planning

    International Nuclear Information System (INIS)

    Plets, David; Joseph, Wout; Aerts, Sam; Vanhecke, Kris; Vermeeren, Guenter; Martens, Luc

    2014-01-01

    In this paper, for the first time a heuristic network calculator for both whole-body exposure due to indoor base station antennas or access points (down-link exposure) and localised exposure due to the mobile device (uplink exposure) in indoor wireless networks is presented. As an application, three phone call scenarios are investigated (Universal Mobile Telecommunications System (UMTS) macro-cell, UMTS femto-cell and WiFi voice-over-IP) and compared with respect to the electric-field strength and localised specific absorption rate (SAR) distribution. Prediction models are created and successfully validated with an accuracy of 3 dB. The benefits of the UMTS power control mechanisms are demonstrated. However, dependent on the macro-cell connection quality and on the user's average phone call connection time, also the macro-cell solution might be preferential from an exposure point of view for the considered scenario. (authors)

  17. Linking canopy reflectance to crop structure and photosynthesis to capture and interpret spatiotemporal dimensions of per-field photosynthetic productivity

    Science.gov (United States)

    Xue, Wei; Jeong, Seungtaek; Ko, Jonghan; Tenhunen, John

    2017-03-01

    Nitrogen and water availability alter canopy structure and physiology, and thus crop growth, yielding large impacts on ecosystem-regulating/production provisions. However, to date, explicitly quantifying such impacts remains challenging partially due to lack of adequate methodology to capture spatial dimensions of ecosystem changes associated with nitrogen and water effects. A data fitting, where close-range remote-sensing measurements of vegetation indices derived from a handheld instrument and an unmanned aerial vehicle (UAV) system are linked to in situ leaf and canopy photosynthetic traits, was applied to capture and interpret inter- and intra-field variations in gross primary productivity (GPP) in lowland rice grown under flooded conditions (paddy rice, PD) subject to three nitrogen application rates and under rainfed conditions (RF) in an East Asian monsoon region of South Korea. Spatial variations (SVs) in both GPP and light use efficiency (LUEcabs) early in the growing season were enlarged by nitrogen addition. The nutritional effects narrowed over time. A shift in planting culture from flooded to rainfed conditions strengthened SVs in GPP and LUEcabs. Intervention of prolonged drought late in the growing season dramatically intensified SVs that were supposed to seasonally decrease. Nevertheless, nitrogen addition effects on SV of LUEcabs at the early growth stage made PD fields exert greater SVs than RF fields. SVs of GPP across PD and RF rice fields were likely related to leaf area index (LAI) development less than to LUEcabs, while numerical analysis suggested that considering strength in LUEcabs and its spatial variation for the same crop type tends to be vital for better evaluation in landscape/regional patterns of ecosystem photosynthetic productivity at critical phenology stages.

  18. MHD modeling for Formation Process of Coronal Mass Ejections: Interaction between Ejecting Flux Rope and Ambient Field

    Science.gov (United States)

    Shiota, Daikou; Kusano, Kanya; Miyoshi, Takahiro; Shibata, Kazunari

    Coronal mass ejections (CMEs), in which large amount of magnetic flux is launched into the interplanetary space, are most explosive phenomena in the solar corona. Due to their large influences to the space environment near the Earth, it is very important to make cleat how CMEs are formed and how determine the field orientations within CMEs. In order to examine the sufficient conditions, we performed three dimensional magnetohydrodynamic simulation of formation processes of CMEs, focusing on interaction (reconnection) between an ejecting flux rope and its ambient field. We examined three cases with different ambient fields: no ambient field, and cases with dipole field of two opposite directions which are parallel and anti-parallel to that of the flux rope surface. As the results, while the flux rope disappears in the anti-parallel case, in other cases the flux ropes can evolve to CMEs and however shows different amount of rotation of the flux rope. The results mean that the interaction between an ejecting flux rope and its ambient field is a significant process for determining CME formation and CME orientation, and also show that the amount and direction of magnetic flux within the flux rope and the ambient field are key parameters for CME formation. Especially, the interaction (reconnection) plays a significant role to the rotation of the flux rope, with a process similar to "tilting instability" in a spheromak-type experiment of laboratory plasma.

  19. Pulsed electric field and combination processing of mango nectar: effect on volatile compounds and HMF formation

    Directory of Open Access Journals (Sweden)

    A. S. Bawa

    2015-01-01

    Full Text Available Mango nectar is a commercially familiar and preferred product. The traditional processing of mango nectar has been by thermal processing which resulted in the alteration of the flavour of the product due to the effect of high temperature. The thermal processing of the nectar also resulted in the production of byproducts of non-enzymatic browning such as 5- hydroxy methyl furfural (HMF. These process induced effects, affect both the nutritive and sensory attributes of the fruit product, making it less preferable. With the growing interest and awareness about the benefits of alternative non-thermal technologies, such as pulsed electric field (PEF, the present work was proposed to use PEF to minimize the loss of volatiles and formation of HMF. The study involves thermal (96 ºC for 300 s and 600 s, PEF (24 µs, 120 Hz and 38 kV/cm and combination processing (PEF + Thermal (96 ºC for 90 s of mango nectar. The effect of these treatments on the volatile composition of mango nectar has been analysed using GC-MS technique. The reduction in the volatile compounds was significant (p 0.05 different from unprocessed sample, proving the fresh-like character of the product.

  20. Evolutionary developmental pathology and anthropology: A new field linking development, comparative anatomy, human evolution, morphological variations and defects, and medicine.

    Science.gov (United States)

    Diogo, Rui; Smith, Christopher M; Ziermann, Janine M

    2015-11-01

    We introduce a new subfield of the recently created field of Evolutionary-Developmental-Anthropology (Evo-Devo-Anth): Evolutionary-Developmental-Pathology-and-Anthropology (Evo-Devo-P'Anth). This subfield combines experimental and developmental studies of nonhuman model organisms, biological anthropology, chordate comparative anatomy and evolution, and the study of normal and pathological human development. Instead of focusing on other organisms to try to better understand human development, evolution, anatomy, and pathology, it places humans as the central case study, i.e., as truly model organism themselves. We summarize the results of our recent Evo-Devo-P'Anth studies and discuss long-standing questions in each of the broader biological fields combined in this subfield, paying special attention to the links between: (1) Human anomalies and variations, nonpentadactyly, homeotic transformations, and "nearest neighbor" vs. "find and seek" muscle-skeleton associations in limb+facial muscles vs. other head muscles; (2) Developmental constraints, the notion of "phylotypic stage," internalism vs. externalism, and the "logic of monsters" vs. "lack of homeostasis" views about human birth defects; (3) Human evolution, reversions, atavisms, paedomorphosis, and peromorphosis; (4) Scala naturae, Haeckelian recapitulation, von Baer's laws, and parallelism between phylogeny and development, here formally defined as "Phylo-Devo parallelism"; and (5) Patau, Edwards, and Down syndrome (trisomies 13, 18, 21), atavisms, apoptosis, heart malformations, and medical implications. © 2015 Wiley Periodicals, Inc.

  1. Quantification of patient specific assay interference in different formats of enzyme linked immunoassays for therapeutic monoclonal antibodies

    NARCIS (Netherlands)

    Grebenchtchikov, N.J.; Geurts-Moespot, A.; Heijmen, L.; Laarhoven, H.W.M. van; Herpen, C.M.L. van; Thijs, A.M.J.; Span, P.N.; Sweep, F.C.

    2014-01-01

    BackgroundThe use of therapeutic monoclonal antibodies for clinical purposes has significantly increased in recent years, and so has the need to monitor antibody concentrations. This may be achieved using the well-established enzyme linked immunoassay (ELISA) methods; however, these assays are

  2. Quantification of patient-specific assay interference in different formats of enzyme-linked immunoassays for therapeutic monoclonal antibodies

    NARCIS (Netherlands)

    Grebenchtchikov, Nicolai; Geurts-Moespot, Anneke J.; Heijmen, Linda; van Laarhoven, Hanneke W. M.; van Herpen, Carla M. L.; Thijs, Annemarie M. J.; Span, Paul N.; Sweep, Fred C. G. J.

    2014-01-01

    The use of therapeutic monoclonal antibodies for clinical purposes has significantly increased in recent years, and so has the need to monitor antibody concentrations. This may be achieved using the well-established enzyme linked immunoassay (ELISA) methods; however, these assays are subject to a

  3. Formation of platinated GG cross-links on DNA by photoactivation of a Pt(IV) azide complex

    Czech Academy of Sciences Publication Activity Database

    Kašpárková, Jana; Mackay, F. S.; Brabec, Viktor; Sadler, P. J.

    2003-01-01

    Roč. 8, č. 7 (2003), s. 741-745 ISSN 0949-8257 R&D Projects: GA AV ČR IAA5004101; GA AV ČR KJB5004301 Institutional research plan: CEZ:AV0Z5004920 Keywords : cross-links * DNA * guanine Subject RIV: BO - Biophysics Impact factor: 3.905, year: 2003

  4. Dune field pattern formation and recent transporting winds in the Olympia Undae Dune Field, north polar region of Mars

    OpenAIRE

    Ewing, Ryan C.; Peyret, Aymeric-Pierre B.; Kocurek, Gary; Bourke, Mary

    2010-01-01

    High-Resolution Imaging Science Experiment (HiRISE) imagery of the central Olympia Undae Dune Field in the north polar region of Mars shows a reticulate dune pattern consisting of two sets of nearly orthogonal dune crestlines, with apparent slipfaces on the primary crests, ubiquitous wind ripples, areas of coarse-grained wind ripples, and deflated interdune areas. Geomorphic evidence and dune field pattern analysis of dune crest length, spacing, defect density, and orientation indicates that ...

  5. SparsePak: A Formatted Fiber Field Unit for the WIYN Telescope Bench Spectrograph. I. Design, Construction, and Calibration

    NARCIS (Netherlands)

    Bershady, Matthew A.; Andersen, David R.; Harker, Justin; Ramsey, Larry W.; Verheijen, Marc A. W.

    2004-01-01

    We describe the design and construction of a formatted fiber field unit, SparsePak, and characterize its optical and astrometric performance. This array is optimized for spectroscopy of low surface brightness extended sources in the visible and near-infrared. SparsePak contains 82, 4.7" fibers

  6. Magnetic Field Effect on Photochemical Thin Film Formation from a Gaseous Mixture of Trimethyl(2-propynyloxy)silane and Glyoxal

    Czech Academy of Sciences Publication Activity Database

    Morita, H.; Kumagai, T.; Bastl, Zdeněk

    2004-01-01

    Roč. 17, č. 1 (2004), s. 53-60 ISSN 0914-9244 Grant - others: MEXT (JP) Area767-15085203 Institutional research plan: CEZ:AV0Z4040901 Keywords : thin film formation * aerosol particles * magnetic field effect Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.024, year: 2002

  7. Mechanistic Links in the in-situ Formation of Dinuclear Manganese Catalysts, H2O2 Disproportionation, and Alkene Oxidation

    NARCIS (Netherlands)

    Angelone, Davide; Abdolahzadeh, Shaghayegh; de Boer, Johannes W.; Browne, Wesley R.

    The oxidation of substrates, such as alkenes, with H2O2 and the catalyst [Mn-2(IV)(mu-O)(3)(tmtacn)(2)](2+) (1; tmtacn = 1,4,7-tri-methyl-1,4,7-triazacyclononane) is promoted by the addition of carboxylic acids through the in situ formation of bis-(carboxylato) complexes of the type

  8. Providing Links to Online Resources for Students. EDNER (Formative Evaluation of the Distributed National Electronic Resource) Project. Issues Paper.

    Science.gov (United States)

    Manchester Metropolitan Univ. (England).

    This issues paper, the fourth in a series of eight, is intended to distill formative evaluation questions on topics that are central to the development of the higher and further education information environment in the United Kingdom. As the online environment becomes a feature of teaching and learning, it offers lecturers the opportunity to…

  9. Evaluation of intraspecific competition (Aspergillus flavus Link) and aflatoxin formation in suspended disc culture and preharvest maize

    Science.gov (United States)

    The abilities of non-aflatoxin producing strains of Aspergillus flavus NRRL 32354; 18543; 21882; 21368 as well as domesticated koji strains Aspergillus oryzae (syn. A. flavus var. oryzae) NRRL 451; 1911; 5592; 6271; 30038 to interfere with aflatoxin formation by A. flavus NRRL 3357; 32355 were exami...

  10. The Kepler Dichotomy in Planetary Disks: Linking Kepler Observables to Simulations of Late-stage Planet Formation

    Science.gov (United States)

    Moriarty, John; Ballard, Sarah

    2016-11-01

    NASA’s Kepler Mission uncovered a wealth of planetary systems, many with planets on short-period orbits. These short-period systems reside around 50% of Sun-like stars and are similarly prevalent around M dwarfs. Their formation and subsequent evolution is the subject of active debate. In this paper, we simulate late-stage, in situ planet formation across a grid of planetesimal disks with varying surface density profiles and total mass. We compare simulation results with observable characteristics of the Kepler sample. We identify mixture models with different primordial planetesimal disk properties that self-consistently recover the multiplicity, radius, period and period ratio, and duration ratio distributions of the Kepler planets. We draw three main conclusions. (1) We favor a “frozen-in” narrative for systems of short-period planets, in which they are stable over long timescales, as opposed to metastable. (2) The “Kepler dichotomy,” an observed phenomenon of the Kepler sample wherein the architectures of planetary systems appear to either vary significantly or have multiple modes, can naturally be explained by formation within planetesimal disks with varying surface density profiles. Finally, (3) we quantify the nature of the “Kepler dichotomy” for both GK stars and M dwarfs, and find that it varies with stellar type. While the mode of planet formation that accounts for high multiplicity systems occurs in 24% ± 7% of planetary systems orbiting GK stars, it occurs in 63% ± 16% of planetary systems orbiting M dwarfs.

  11. Field Demonstration of Carbon Dioxide Miscible Flooding in the Lansing-Kansas City Formation, Central Kansas

    Energy Technology Data Exchange (ETDEWEB)

    Alan Byrnes; G. Paul Willhite; Don Green; Richard Pancake; JyunSyung Tsau; W. Lynn Watney; John Doveton; Willard Guy; Rodney Reynolds; Dave Murfin; James Daniels; Russell Martin; William Flanders; Dave Vander Griend; Eric Mork; Paul Cantrell

    2010-03-07

    A pilot carbon dioxide miscible flood was initiated in the Lansing Kansas City C formation in the Hall Gurney Field, Russell County, Kansas. The reservoir zone is an oomoldic carbonate located at a depth of about 2900 feet. The pilot consists of one carbon dioxide injection well and three production wells. Continuous carbon dioxide injection began on December 2, 2003. By the end of June 2005, 16.19 MM lb of carbon dioxide was injected into the pilot area. Injection was converted to water on June 21, 2005 to reduce operating costs to a breakeven level with the expectation that sufficient carbon dioxide was injected to displace the oil bank to the production wells by water injection. By March 7,2010, 8,736 bbl of oil were produced from the pilot. Production from wells to the northwest of the pilot region indicates that oil displaced from carbon dioxide injection was produced from Colliver A7, Colliver A3, Colliver A14 and Graham A4 located on adjacent leases. About 19,166 bbl of incremental oil were estimated to have been produced from these wells as of March 7, 2010. There is evidence of a directional permeability trend toward the NW through the pilot region. The majority of the injected carbon dioxide remains in the pilot region, which has been maintained at a pressure at or above the minimum miscibility pressure. Estimated oil recovery attributed to the CO2 flood is 27,902 bbl which is equivalent to a gross CO2 utilization of 4.8 MCF/bbl. The pilot project is not economic.

  12. Dune field pattern formation and recent transporting winds in the Olympia Undae Dune Field, north polar region of Mars

    Science.gov (United States)

    Ewing, Ryan C.; Peyret, Aymeric-Pierre B.; Kocurek, Gary; Bourke, Mary

    2010-08-01

    High-Resolution Imaging Science Experiment (HiRISE) imagery of the central Olympia Undae Dune Field in the north polar region of Mars shows a reticulate dune pattern consisting of two sets of nearly orthogonal dune crestlines, with apparent slipfaces on the primary crests, ubiquitous wind ripples, areas of coarse-grained wind ripples, and deflated interdune areas. Geomorphic evidence and dune field pattern analysis of dune crest length, spacing, defect density, and orientation indicates that the pattern is complex, representing two constructional generations of dunes. The oldest and best-organized generation forms the primary crestlines and is transverse to circumpolar easterly winds. Gross bed form-normal analysis of the younger pattern of crestlines indicates that it emerged with both circumpolar easterly winds and NE winds and is reworking the older pattern. Mapping of secondary flow fields over the dunes indicates that the most recent transporting winds were from the NE. The younger pattern appears to represent an influx of sediment to the dune field associated with the development of the Olympia Cavi reentrant, with NE katabatic winds channeling through the reentrant. A model of the pattern reformation based upon the reconstructed primary winds and resulting secondary flow fields shows that the development of the secondary pattern is controlled by the boundary condition of the older dune topography.

  13. γ-PGA and MTGase improve the formation of ε-(γ-glutamyl) lysine cross-links within hairtail (Trichiurus haumela) surimi protein.

    Science.gov (United States)

    Hu, Yaqin; Shao, Ying; Wu, Chunhua; Yuan, Chunhong; Ishimura, Gakushi; Liu, Wenjuan; Chen, Shiguo

    2018-03-01

    The present study investigated the mechanism of ε-(γ-glutamyl) lysine cross-links within hairtail (Trichiurus haumela) surimi protein via γ-polyglutamic acid (γ-PGA) and MTGase. The results indicated that the addition of MTGase and γ-PGA markedly improved the gelation properties of hairtail surimi protein, including its maximum breaking force and deformation, water holding capacity and gel strength. The maximum improvements were achieved by adding 0.5units MTGase/g meat paste in combination with 0.06% γ-PGA. SDS-PAGE showed that the band intensity of cross-linked proteins increased, whereas that of myosin heavy chain decreased after treatments. Further scanning electron microscopy (SEM) analysis showed the formation of a denser gel matrix, which was caused by much stronger and more inter- and intra-molecular cross-linking of proteins, via MTGase catalysing ε-(γ-glutamyl) lysine cross-links formed between lysine residues in the gel protein and glutamic residues in the hydrolytic γ-PGA. The results provide reliable guidance for the improvement of hairtail surimi protein gelation properties. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Aminothiols linked to quinoline and acridine chromophores efficiently decrease 7,8-dihydro-8-oxo-2'-deoxyguanosine formation in γ-irradiated DNA

    International Nuclear Information System (INIS)

    Laayoun, A.; Coulombeau, C.; Constant, J.F.; Lhomme, J.; Berger, M.; Cadet, J.

    1994-01-01

    In a search for more active radioprotective compounds, we have prepared and examined a series of model molecules in which the radioprotective β-aminothiol unit (free or derivatized as acetate or phosphorothioate) is tethered to the DNA-binding chromophores quinoline and acridine through links of variable length. The modifying activity of these 'hybrid' molecules was estimated by measuring the formation of 8-oxo-2'-deoxyguanosine (8-oxodGuo) in double-strand DNA upon exposure to γ-rays in oxygen-free solution in the presence of the drugs. We show that all hybrid molecules protect the guanine moiety from oxidation more efficiently than the parent β-aminothiol units. The degree of protection is the highest for the molecules in which the thiol is linked to the strong binding intercalator acridine through a long polyaminochain. (author)

  15. Influence of abnormally high formation pressure on the porosity of reservoirs (on the example of Solokhovsk field)

    Energy Technology Data Exchange (ETDEWEB)

    Bakhtin, V.V.; Omelin, V.M.

    1980-01-01

    Productive horizons of the Solokhovsk field are composed of alternating claystones, siltstones, and sandstones. Samples of rocks were investigated by using the automatic electronic analyzer, Kvantimet-720. It was found that abnormally high formation pressure causes a decompaction effect. This effect is observed not only in clays which cover a deposit, but also in reservoirs of the deposit. Increases in pore dimensions and in average area of pores are the consequences of the decompaction effect. An extent of decompaction effect in consolidated formations in zones of abnormally high formation pressure depends on an intensity of secondary local epigenetic processes. These processes take place in zones of abnormally high formation pressure and in aureoles of hydrocarbon inculcation.

  16. ICBP90, a novel methyl K9 H3 binding protein linking protein ubiquitination with heterochromatin formation.

    Science.gov (United States)

    Karagianni, Panagiota; Amazit, Larbi; Qin, Jun; Wong, Jiemin

    2008-01-01

    Methylation of histone H3 on lysine 9 is critical for diverse biological processes including transcriptional repression, heterochromatin formation, and X inactivation. The biological effects of histone methylation are thought to be mediated by effector proteins that recognize and bind to specific patterns of methylation. Using an unbiased in vitro biochemical approach, we have identified ICBP90, a transcription and cell cycle regulator, as a novel methyl K9 H3-specific binding protein. ICBP90 and its murine homologue Np95 are enriched in pericentric heterochromatin of interphase nuclei, and this localization is dependent on H3K9 methylation. Specific binding of ICBP90 to methyl K9 H3 depends on two functional domains, a PHD (plant homeodomain) finger that defines the binding specificity and an SRA (SET- and RING-associated) domain that promotes binding activity. Furthermore, we present evidence that ICBP90 is required for proper heterochromatin formation in mammalian cells.

  17. Linking the formation of molecular clouds and high-mass stars: a multi-tracer and multi-scale study

    International Nuclear Information System (INIS)

    Nguyen-Luong, Quang

    2012-01-01

    Star formation is a complex process involving many physical processes acting from the very large scales of the galaxy to the very small scales of individual stars. Among the highly debated topics, the gas to star-formation-rate (SFR) relation is an interesting topic for both the galactic and extragalactic communities. Although it is studied extensively for external galaxies, how this relation behaves with respect to the molecular clouds of the Milky Way is still unclear. The detailed mechanisms of the formation of molecular clouds and stars, especially high-mass stars, are still not clear. To tackle these two questions, we investigate the molecular cloud formation and the star formation activities in the W43 molecular cloud complex and the G035.39-00.33 filament. The first goal is to infer the connections of the gas-SFR relations of these two objects to those of other galactic molecular clouds and to extragalactic ones. The second goal is to look for indications that the converging flows theory has formed the W43 molecular cloud since it is the first theory to explain star formation self-consistently, from the onset of molecular clouds to the formation of seeds of (high-mass) stars. We use a large dataset of continuum tracers at 3.6--870 μm extracted from Galaxy-wide surveys such as HOBYS, EPOS, Hi-GAL, ATLASGAL, GLIMPSE, and MIPSGAL to trace the cloud structure, mass and star formation activities of both the W43 molecular cloud complex and the G035.39-00.33 filament. To explore the detailed formation mechanisms of the molecular cloud in W43 from low-density to very high-density gas, we take advantage of the existing H I , 13 CO 1-0 molecular line data from the VGPS and GRS surveys in combination with the new dedicated molecular line surveys with the IRAM 30 m. We characterise the W43 molecular complex as being a massive complex (M(total) ∼ 7.1 *10 6 M. over spatial extent of ∼ 140 pc), which has a high concentration of dense clumps (M(clumps) ∼ 8.4*10 5 M

  18. Nitrogen plasma formation through terahertz-induced ultrafast electron field emission

    DEFF Research Database (Denmark)

    Iwaszczuk, Krzysztof; Zalkovskij, Maksim; Strikwerda, Andrew

    2015-01-01

    Electron microscopy and electron diffraction techniques rely on electron sources. Those sources require strong electric fields to extract electrons from metals, either by the photoelectric effect, driven by multiphoton absorption of strong laser fields, or in the static field emission regime...

  19. Their Modernity Matters Too: The Invisible Links Between Black Atlantic Identity Formations in the Caribbean and Consumer Capitalism

    NARCIS (Netherlands)

    Guadeloupe, F.E.

    2009-01-01

    Much work in the field of Black Atlantic studies has highlighted the lives and philosophies of liberation of black savants such as W. E. B. DuBois and Claude McKay. These and other black intellectuals, who combined anti-capitalist critique with the struggle against anti-black racism, have been

  20. Their modernity matters too: the invisible links between Black Atlantic identity formations in the Caribbean and consumer capitalism

    NARCIS (Netherlands)

    Guadeloupe, F.

    2009-01-01

    Much work in the field of Black Atlantic studies has highlighted the lives and philosophies of liberation of black savants such as W. E. B. DuBois and Claude McKay. These and other black intellectuals, who combined anti-capitalist critique with the struggle against anti-black racism, have been

  1. Mechanisms and time-resolved dynamics for trihydrogen cation (H 3 +) formation from organic molecules in strong laser fields

    Science.gov (United States)

    Ekanayake, N.; Nairat, M.; Kaderiya, B.; Feizollah, P.; Jochim, B.; Severt, T.; Berry, B.; Kanaka Raju, P.; Carnes, K. D.; Pathak, S.; Rolles, D.; Rudenko, A.; Ben-Itzhak, I.; Jackson, J. E.; Levine, B. G.; Dantus, M.

    2017-04-01

    Strong-field laser-matter interactions often lead to exotic chemical reactions. H3+formation from organic molecules is one such case which requires multiple bonds to break and form. Here, we present the first experimental evidence for the existence of two different reaction mechanisms for H3+formation from organic molecules irradiated by a strong-field laser. The assignment of the two different mechanisms was accomplished through the strong-field ionization of methanol isotopomers, ethylene glycol, and acetone. Our findings are supported by femtosecond time-resolved measurements, coincidence measurements, and ab initio calculations with the most plausible transition states involved in the two mechanisms. This exotic chemical reaction is important as it shows that a strong laser field can not only selectively break multiple bonds but also can lead to the formation of multiple new bonds within an extremely short timescale, on the order of 100 femtoseconds. This work is supported by the U.S. Department of Energy under Grants DOE SISGR (DE-SC0002325) and DE-FG02-86ER13491.

  2. Exact Bethe ansatz solution of a nonlinear quantum field model in quasi-two dimensions linked to the Landau–Lifshitz equation

    Energy Technology Data Exchange (ETDEWEB)

    Kundu, Anjan, E-mail: anjan.kundu@saha.ac.in

    2016-12-15

    Integrable quantum field models are known to exist mostly in one space-dimension. Exploiting the concept of multi-time in integrable systems and a Lax matrix of higher scaling order, we construct a novel quantum field model in quasi-two dimensions involving interacting fields. The Yang–Baxter integrability is proved for the model by finding a new kind of commutation rule for its basic fields, representing nonstandard scalar fields along the transverse direction. In spite of a close link with the quantum Landau–Lifshitz equation, the present model differs widely from it, in its content and the result obtained. Using further the algebraic Bethe ansatz we solve exactly the eigenvalue problem of this quantum field model for all its higher conserved operators. The idea presented here should instigate the construction of a novel class of integrable field and lattice models and exploration of a new type of underlying algebras.

  3. Formation of two hydrogen bonds from the globin to the heme-linked oxygen molecule in Ascaris hemoglobin.

    Science.gov (United States)

    De Baere, I; Perutz, M F; Kiger, L; Marden, M C; Poyart, C

    1994-02-15

    We have tried to find out why Ascaris hemoglobin has such an exceptionally high oxygen affinity (P50 approximately 0.004 mmHg; 1 mmHg = 133 Pa). Following Kloek et al., we have synthesized the N-terminal globin domain of Ascaris hemoglobin in Escherichia coli [Kloek, A. P., Yang, J., Mathews, F. S. & Goldberg, D. (1993) J. Biol. Chem. 268, 17669-17671]. Like Kloek et al., we found its oxygen affinity to be as high as that of native Ascaris hemoglobin. We thought that this high affinity might be due to the heme-bound oxygen molecule being stabilized by two hydrogen bonds from the globin instead of the usual one. Ascaris hemoglobin has a distal glutamine instead of the more usual histidine as one of the potential hydrogen bond donors. In addition, it contains a tyrosine at position 10 of B helix (B10) in place of the leucine generally found there in vertebrate myoglobins and hemoglobins. Following the discovery of Carver et al. that sperm whale myoglobin with the replacement of leucine B10 by phenylalanine has a raised oxygen affinity, we have replaced tyrosine B10 in the N-terminal domain of Ascaris hemoglobin by either leucine or phenylalanine [Carver, T. E., Brantley, R. E., Jr., Singleton, E. W., Arduini, R. M., Quillin, H. L., Phillips, G. N., Jr., & Olson, J. S. (1992) J. Biol. Chem. 267, 14443-14450]. Either of these replacements lowered the oxygen affinity about 100-fold, to the same level of that of human alpha-globin chains. These results are consistent with a hydrogen bond linking the tyrosine hydroxyl to the heme-linked oxygen, with a bond energy of 2.7 kcal/mol.

  4. A parametric study of AC electric field-induced toroidal vortex formation in laminar nonpremixed coflow flames

    KAUST Repository

    Xiong, Yuan

    2017-05-02

    This study presents an experimental work investigating the controlling parameters on the formation of an electrically-induced inner toroidal vortex (ITV) near a nozzle rim in small, laminar nonpremixed coflow flames, when an alternating current is applied to the nozzle. A systematic parametric study was conducted by varying the flow parameters of the fuel and coflowing-air velocities, and the nozzle diameter. The fuels tested were methane, ethylene, ethane, propane, n-butane, and i-butane, each representing different ion-generation characteristics and sooting tendencies. The results showed that the fluid dynamic effects on ITV formation were weak, causing only mild variation when altering flow velocities. However, increased fuel velocity resulted in increased polycyclic aromatic hydrocarbon (PAH) formation, which promoted ITV formation. When judging the ITV-formation tendency based on critical applied voltage and frequency, it was qualitatively well correlated with the PAH concentration and the relative location of PAHs to the nozzle rim. The sooting tendency of the fuels did not affect the results much. A change in the nozzle diameter highlighted the importance of the relative distance between the PAH zone and the nozzle rim, indicating the role of local electric-field intensity on ITV formation. Detailed onset conditions, characteristics of near-nozzle flow patterns, and PAH distributions are also discussed.

  5. Global enhancement and structure formation of the magnetic field in spiral galaxies

    Science.gov (United States)

    Khoperskov, Sergey A.; Khrapov, Sergey S.

    2018-01-01

    In this paper we study numerically large-scale magnetic field evolution and its enhancement in gaseous disks of spiral galaxies. We consider a set of models with the various spiral pattern parameters and the initial magnetic field strength with taking into account gas self-gravity and cooling and heating processes. In agreement with previous studies we find out that galactic magnetic field is mostly aligned with gaseous structures, however small-scale gaseous structures (spurs and clumps) are more chaotic than the magnetic field structure. In spiral arms magnetic field often coexists with the gas distribution, in the inter-arm region we see filamentary magnetic field structure. These filaments connect several isolated gaseous clumps. Simulations reveal the presence of the small-scale irregularities of the magnetic field as well as the reversal of magnetic field at the outer edge of the large-scale spurs. We provide evidences that the magnetic field in the spiral arms has a stronger mean-field component, and there is a clear inverse correlation between gas density and plasma-beta parameter, compared to the rest of the disk with a more turbulent component of the field and an absence of correlation between gas density and plasma-beta. We show the mean field growth up to >3-10 μG in the cold gas during several rotation periods (>500-800 Myr), whereas ratio between azimuthal and radial field is equal to >4/1. We find an enhancement of random and ordered components of the magnetic field. Mean field strength increases by a factor of >1.5-2.5 for models with various spiral pattern parameters. Random magnetic field component can reach up to 25% from the total strength. By making an analysis of the time-dependent evolution of the radial Poynting flux, we point out that the magnetic field strength is enhanced more strongly at the galactic outskirts which is due to the radial transfer of magnetic energy by the spiral arms pushing the magnetic field outward. Our results also

  6. Formation of Nup98-containing nuclear bodies in HeLa sublines is linked to genomic rearrangements affecting chromosome 11.

    Science.gov (United States)

    Romana, Serge; Radford-Weiss, Isabelle; Lapierre, Jean-Michel; Doye, Valérie; Geoffroy, Marie-Claude

    2016-09-01

    Nup98 is an important component of the nuclear pore complex (NPC) and also a rare but recurrent target for chromosomal translocation in leukaemogenesis. Nup98 contains multiple cohesive Gly-Leu-Phe-Gly (GLFG) repeats that are critical notably for the formation of intranuclear GLFG bodies. Previous studies have reported the existence of GLFG bodies in cells overexpressing exogenous Nup98 or in a HeLa subline (HeLa-C) expressing an unusual elevated amount of endogenous Nup98. Here, we have analysed the presence of Nup98-containing bodies in several human cell lines. We found that HEp-2, another HeLa subline, contains GLFG bodies that are distinct from those identified in HeLa-C. Rapid amplification of cDNA ends (RACE) revealed that HEp-2 cells express additional truncated forms of Nup98 fused to a non-coding region of chromosome 11q22.1. Cytogenetic analyses using FISH and array-CGH further revealed chromosomal rearrangements that were distinct from those observed in leukaemic cells. Indeed, HEp-2 cells feature a massive amplification of juxtaposed NUP98 and 11q22.1 loci on a chromosome marker derived from chromosome 3. Unexpectedly, minor co-amplifications of NUP98 and 11q22.1 loci were also observed in other HeLa sublines, but on rearranged chromosomes 11. Altogether, this study reveals that distinct genomic rearrangements affecting NUP98 are associated with the formation of GLFG bodies in specific HeLa sublines.

  7. Identification of new protein-protein and protein-DNA interactions linked with wood formation in Populus trichocarpa.

    Science.gov (United States)

    Petzold, H Earl; Rigoulot, Stephen B; Zhao, Chengsong; Chanda, Bidisha; Sheng, Xiaoyan; Zhao, Mingzhe; Jia, Xiaoyan; Dickerman, Allan W; Beers, Eric P; Brunner, Amy M

    2018-03-01

    Cellular processes, such as signal transduction and cell wall deposition, are organized by macromolecule interactions. Experimentally determined protein-protein interactions (PPIs) and protein-DNA interactions (PDIs) relevant to woody plant development are sparse. To begin to develop a Populus trichocarpa Torr. & A. Gray wood interactome, we applied the yeast-two-hybrid (Y2H) assay in different ways to enable the discovery of novel PPIs and connected networks. We first cloned open reading frames (ORFs) for 361 genes markedly upregulated in secondary xylem compared with secondary phloem and performed a binary Y2H screen with these proteins. By screening a xylem cDNA library for interactors of a subset of these proteins and then recapitulating the process by using a subset of the interactors as baits, we ultimately identified 165 PPIs involving 162 different ORFs. Thirty-eight transcription factors (TFs) included in our collection of P. trichocarpa wood ORFs were used in a Y1H screen for binding to promoter regions of three genes involved in lignin biosynthesis resulting in 40 PDIs involving 20 different TFs. The network incorporating both the PPIs and PDIs included 14 connected subnetworks, with the largest having 132 members. Protein-protein interactions and PDIs validated previous reports and also identified new candidate wood formation proteins and modules through their interactions with proteins and promoters known to be involved in secondary cell wall synthesis. Selected examples are discussed including a PPI between Mps one binder (MOB1) and a mitogen-activated protein kinase kinase kinase kinase (M4K) that was further characterized by assays confirming the PPI as well as its effect on subcellular localization. Mapping of published transcriptomic data showing developmentally detailed expression patterns across a secondary stem onto the network supported that the PPIs and PDIs are relevant to wood formation, and also illustrated that wood

  8. Effective Beginning Handwriting Instruction: Multi-modal, Consistent Format for 2 Years, and Linked to Spelling and Composing.

    Science.gov (United States)

    Wolf, Beverly; Abbott, Robert D; Berninger, Virginia W

    2017-02-01

    In Study 1, the treatment group ( N = 33 first graders, M = 6 years 10 months, 16 girls) received Slingerland multi-modal (auditory, visual, tactile, motor through hand, and motor through mouth) manuscript (unjoined) handwriting instruction embedded in systematic spelling, reading, and composing lessons; and the control group ( N =16 first graders, M = 7 years 1 month, 7 girls) received manuscript handwriting instruction not systematically related to the other literacy activities. ANOVA showed both groups improved on automatic alphabet writing from memory; but ANCOVA with the automatic alphabet writing task as covariate showed that the treatment group improved significantly more than control group from the second to ninth month of first grade on dictated spelling and recognition of word-specific spellings among phonological foils. In Study 2 new groups received either a second year of manuscript ( N = 29, M = 7 years 8 months, 16 girls) or introduction to cursive (joined) instruction in second grade ( N = 24, M = 8 years 0 months, 11 girls) embedded in the Slingerland literacy program. ANCOVA with automatic alphabet writing as covariate showed that those who received a second year of manuscript handwriting instruction improved more on sustained handwriting over 30, 60, and 90 seconds than those who had had only one year of manuscript instruction; both groups improved in spelling and composing from the second to ninth month of second grade. Results are discussed in reference to mastering one handwriting format before introducing another format at a higher grade level and always embedding handwriting instruction in writing and reading instruction aimed at all levels of language.

  9. Thrombin-linked aptamer assay for detection of platelet derived growth factor BB on magnetic beads in a sandwich format.

    Science.gov (United States)

    Guo, Limin; Zhao, Qiang

    2016-09-01

    Here we describe a thrombin-linked aptamer assay (TLAA) for protein by using thrombin as an enzyme label, harnessing enzyme activity of thrombin and aptamer affinity binding. TLAA converts detection of specific target proteins to the detection of thrombin by using a DNA sequence that consists of two aptamers with the first aptamer binding to the specific target protein and the second aptamer binding to thrombin. Through the affinity binding, the thrombin enzyme is labeled on the protein target, and thrombin catalyzes the hydrolysis of small peptide substrate into product, generating signals for quantification. As a proof of principle, we show a sandwich TLAA for platelet derived growth factor BB (PDGF-BB) by using anti-PDGF-BB antibody coated on magnetic beads and an oligonucleotide containing the aptamer for PDGF-BB and the aptamer for thrombin. The binding of PDGF-BB to both the antibody and the aptamer results in labeling the complex with thrombin. We achieved detection of PDGF-BB at 16 pM. This TLAA contributes a new application of thrombin and its aptamer in bioanalysis, and shows potentials in assay developments. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Deep-ocean field test of methane hydrate formation from a remotely operated vehicle

    Science.gov (United States)

    Brewer, Peter G.; Orr, Franklin M., Jr.; Friederich, Gernot; Kvenvolden, Keith A.; Orange, Daniel L.; McFarlane, James; Kirkwood, William

    1997-05-01

    We have observed the process of formation of clathrate hydrates of methane in experiments conducted on the remotely operated vehicle (ROV) Ventana in the deep waters of Monterey Bay. A tank of methane gas, acrylic tubes containing seawater, and seawater plus various types of sediment were carried down on Ventana to a depth of 910 m where methane gas was injected at the base of the acrylic tubes by bubble stream. Prior calculations had shown that the local hydrographic conditions gave an upper limit of 525 m for the P-T boundary defining methane hydrate formation or dissociation at this site, and thus our experiment took place well within the stability range for this reaction to occur. Hydrate formation in free seawater occurred within minutes as a buoyant mass of translucent hydrate formed at the gas-water interface. In a coarse sand matrix the filling of the pore spaces with hydrate turned the sand column into a solidified block, which gas pressure soon lifted and ruptured. In a fine-grained black mud the gas flow carved out flow channels, the walls of which became coated and then filled with hydrate in larger discrete masses. Our experiment shows that hydrate formation is rapid in natural seawater, that sediment type strongly influences the patterns of hydrate formation, and that the use of ROV technologies permits the synthesis of large amounts of hydrate material in natural systems under a variety of conditions so that fundamental research on the stability and growth of these substances is possible.

  11. Formation and frequency response of two-dimensional nanowire lattices in an applied electric field.

    Science.gov (United States)

    Boehm, Sarah J; Lin, Lan; Guzmán Betancourt, Kimberly; Emery, Robyn; Mayer, Jeffrey S; Mayer, Theresa S; Keating, Christine D

    2015-06-02

    Ordered two-dimensional (2D) lattices were formed by assembling silica-coated solid and segmented Au nanowires between coplanar electrodes using alternating current (ac) electric fields. Dielectrophoretic forces from the ac field concentrated wires between the electrodes, with their long axis aligned parallel to the field lines. After reaching a sufficient particle density, field-induced dipolar interactions resulted in the assembly of dense 2D lattices that spanned the electrodes, a distance of at least ten wire lengths. The ends of neighboring Au wires or segments overlapped a fraction of their length to form lattice structures with a "running bond" brickwork-like pattern. The observed lattice structures were tunable in three distinct ways: (1) particle segmentation pattern, which fixed the lattice periodicity for a given field condition; (2) ac frequency, which varied lattice periodicity in real time; and (3) switching the field on/off, which converted between lattice and smectic particle organizations. Electric field simulations were performed to understand how the observed lattice periodicity depends on the assembly conditions and particle segmentation. Directed self-assembly of well-ordered 2D metallic nanowire lattices that can be designed by Au striping pattern and reconfigured by changes in field conditions could enable new types of switchable optical or electronic devices.

  12. Programed oil generation of the Zubair Formation, Southern Iraq oil fields: Results from Petromod software modeling and geochemical analysis

    Science.gov (United States)

    Al-Ameri, T. K.; Pitman, Janet K.; Naser, M.E.; Zumberge, J.; Al-Haydari, H. A.

    2011-01-01

    1D petroleum system modeling was performed on wells in each of four oil fields in South Iraq, Zubair (well Zb-47), Nahr Umr (well NR-9), West Qurna (well WQ-15 and 23), and Majnoon (well Mj-8). In each of these fields, deposition of the Zubair Formation was followed by continuous burial, reaching maximum temperatures of 100°C (equivalent to 0.70%Ro) at depths of 3,344–3,750 m of well Zb-47 and 3,081.5–3,420 m of well WQ-15, 120°C (equivalent to 0.78%Ro) at depths of 3,353–3,645 m of well NR-9, and 3,391–3,691.5 m of well Mj-8. Generation of petroleum in the Zubair Formation began in the late Tertiary, 10 million years ago. At present day, modeled transformation ratios (TR) indicate that 65% TR of its generation potential has been reached in well Zb-47, 75% TR in well NR-9 and 55-85% TR in West Qurna oil field (wells WQ-15 and WQ-23) and up to 95% TR in well Mj-8, In contrast, younger source rocks are immature to early mature (petroleum potential of 0.4–9.98 of good hydrocarbon generation, which is consistent with 55–95% hydrocarbon efficiency. These generated hydrocarbons had charged (in part) the Cretaceous and Tertiary reservoirs, especially the Zubair Formation itself, in the traps formed by Alpine collision that closed the Tethys Ocean between Arabian and Euracian Plates and developed folds in Mesopotamian Basin 15–10 million years ago. These traps are mainly stratigraphic facies of sandstones with the shale that formed during the deposition of the Zubair Formation in transgression and regression phases within the main structural folds of the Zubair, Nahr Umr, West Qurna and Majnoon Oil fields. Oil biomarkers of the Zubair Formation Reservoirs are showing source affinity with mixed oil from the Upper Jurassic and Lower Cretaceous strata, including Zubair Formation organic matters, based on presentation of GC and GC-MS results on diagrams of global petroleum systems.

  13. Magnetic neutral sheets in evolving fields. I - General theory. II - Formation of the solar corona

    Science.gov (United States)

    Parker, E. N.

    1983-01-01

    The problem of the hydrostatic equilibrium of a large-scale magnetic field embedded in a fluid with infinite electrical conductivity is considered. It is pointed out that a necessary condition for static equilibrium is the invariance of the small-scale pattern in the field along the large-scale direction. A varying topological pattern implies that no fluid pressure distribution exists for which the field is everywhere static. Magnetic neutral sheets form, and dynamical reconnection of the field takes place. It is shown here that the invariance is also a sufficient condition for the existence of a fluid pressure distribution producing static equilibrium. Even in the simplest cases, however, the requirements on the fluid pressure are extreme and, a priori, are unlikely. It is concluded that almost all twisted flux tubes packed together produce dynamical nonequilibrium and dissipation of their twisting. This is the basic effect underlying the long-standing conjecture that the shuffling of the footpoints of the bipolar magnetic fields in the sun is responsible for heating the active corona. Attention is then given to the consequences of this general dynamical dissipation in the magnetic fields that produce the active corona of the sun. The footpoints of the field are continually manipulated by the subphotospheric convection in such a way that the lines of force are continually wrapped and rotated about one another.

  14. Petrophysical investigations to both Rudeis and Kareem formations, Ras Ghara oil field, Gulf of Suez, Egypt

    Directory of Open Access Journals (Sweden)

    A.A. El-Khadragy

    2017-06-01

    In this research, Tech-log software is used to evaluate the petrophysical characteristics of the studied formations in the form of litho-saturation plots which are considered as an important vertical representation because they are used for more accurate evaluation in the individual wells in the comparison between different wells.

  15. Differentially expressed genes linked to natural variation in long-term memory formation in Cotesia parasitic wasps

    Directory of Open Access Journals (Sweden)

    Joke J. F. A. Van Vugt

    2015-09-01

    Full Text Available Even though learning and memory are universal traits in the Animal Kingdom, closely related species reveal substantial variation in learning rate and memory dynamics. To determine the genetic background of this natural variation, we studied two congeneric parasitic wasp species, Cotesia glomerata and C. rubecula, which lay their eggs in caterpillars of the large and small cabbage white butterfly. A successful egg laying event serves as an unconditioned stimulus in a classical conditioning paradigm, where plant odors become associated to the encounter of a suitable host caterpillar. Depending on the host species, the number of conditioning trials and the parasitic wasp species, three different types of transcription-dependent long-term memory (LTM and one type of transcription-independent, anesthesia-resistant memory (ARM can be distinguished. To identify transcripts underlying these differences in memory formation, we isolated mRNA from parasitic wasp heads at three different time points between induction and consolidation of each of the four memory types, and for each sample three biological replicates, where after strand-specific paired-end 100 bp deep sequencing. Transcriptomes were assembled de novo and differential expression was determined for each memory type and time point after conditioning, compared to unconditioned wasps. Most differentially expressed (DE genes and antisense transcripts were only DE in one of the LTM types. Among the DE genes that were DE in two or more LTM types, were many protein kinases and phosphatases, small GTPases, receptors and ion channels. Some genes were DE in opposing directions between any of the LTM memory types and ARM, suggesting that ARM in Cotesia requires the transcription of genes inhibiting LTM or vice versa. We discuss our findings in the context of neuronal functioning, including RNA splicing and transport, epigenetic regulation, neurotransmitter/peptide synthesis and antisense transcription. In

  16. Distinct cis-acting regions control six6 expression during eye field and optic cup stages of eye formation.

    Science.gov (United States)

    Ledford, Kelley L; Martinez-De Luna, Reyna I; Theisen, Matthew A; Rawlins, Karisa D; Viczian, Andrea S; Zuber, Michael E

    2017-06-15

    The eye field transcription factor, Six6, is essential for both the early (specification and proliferative growth) phase of eye formation, as well as for normal retinal progenitor cell differentiation. While genomic regions driving six6 optic cup expression have been described, the sequences controlling eye field and optic vesicle expression are unknown. Two evolutionary conserved regions 5' and a third 3' to the six6 coding region were identified, and together they faithfully replicate the endogenous X. laevis six6 expression pattern. Transgenic lines were generated and used to determine the onset and expression patterns controlled by the regulatory regions. The conserved 3' region was necessary and sufficient for eye field and optic vesicle expression. In contrast, the two conserved enhancer regions located 5' of the coding sequence were required together for normal optic cup and mature retinal expression. Gain-of-function experiments indicate endogenous six6 and GFP expression in F 1 transgenic embryos are similarly regulated in response to candidate trans-acting factors. Importantly, CRISPR/CAS9-mediated deletion of the 3' eye field/optic vesicle enhancer in X. laevis, resulted in a reduction in optic vesicle size. These results identify the cis-acting regions, demonstrate the modular nature of the elements controlling early versus late retinal expression, and identify potential regulators of six6 expression during the early stages of eye formation. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Formation of microbeads during vapor explosions of Field's metal in water

    KAUST Repository

    Kouraytem, Nadia

    2016-06-17

    We use high-speed video imaging to investigate vapor explosions during the impact of a molten Field\\'s metal drop onto a pool of water. These explosions occur for temperatures above the Leidenfrost temperature and are observed to occur in up to three stages as the metal temperature is increased, with each explosion being more powerful that the preceding one. The Field\\'s metal drop breaks up into numerous microbeads with an exponential size distribution, in contrast to tin droplets where the vapor explosion deforms the metal to form porous solid structures. We compare the characteristic bead size to the wavelength of the fastest growing mode of the Rayleigh-Taylor instability.

  18. Planck intermediate results XXXV. Probing the role of the magnetic field in the formation of structure in molecular clouds

    DEFF Research Database (Denmark)

    Ade, P. A. R.; Aghanim, N.; Alves, M. I. R.

    2016-01-01

    Within ten nearby (d molecular clouds we evaluate statistically the relative orientation between the magnetic field projected on the plane of sky, inferred from the polarized thermal emission of Galactic dust observed by Planck at 353 GHz, and the gas column density structures...... with increasing N-H, from mostly parallel or having no preferred orientation to mostly perpendicular. In simulations of magnetohydrodynamic turbulence in molecular clouds this trend in relative orientation is a signature of Alfvenic or sub-Alfvenic turbulence, implying that the magnetic field is significant...... for the gas dynamics at the scales probed by Planck. We compare the deduced magnetic field strength with estimates we obtain from other methods and discuss the implications of the Planck observations for the general picture of molecular cloud formation and evolution....

  19. How to link pyrene to its host lipid to minimize the extent of membrane perturbations and to optimize pyrene dimer formation

    DEFF Research Database (Denmark)

    Franova, M. D.; Repakova, J.; Holopainen, J. M.

    2014-01-01

    moiety is attached to the hydrocarbon chain. This is in contrast to saturated membranes, where pyrene-induced perturbations have been observed to be more prominent. Meanwhile, the formation of pyrene dimers depends on the linkage point between pyrene and its host lipid. Membrane-spanning dimers between......We study how lipid probes based on pyrene-labeling could be designed to minimize perturbations in lipid bilayers, and how the same design principles could be exploited to develop probes which gauge lipid dynamics primarily within a single lipid monolayer or between them. To this end, we use...... lipids in different membrane leaflets are observed only if the pyrene moiety is attached to the latter half of the acyl chain. A seemingly minor change to link pyrene to an acyl chain that is two carbons shorter leads to a situation where membrane-spanning dimers are no longer observed. Further...

  20. Discussion on uranium ore-formation age in Xiazhuang ore-field, northern Guangdong

    International Nuclear Information System (INIS)

    Wu Lieqin; Tan Zhengzhong; Liu Ruzhou; Huang Guolong

    2003-01-01

    There exist two genetic types of granite-type uranium deposits, i.e. the early-stage one, and the late-stage one. The early-stage uranium deposits are characterized by ore-formation ages of 122-138 Ma, and are high-grade uranium deposits of postmagmatic hydrothermal origin. The late-stage uranium deposits have ore-formation ages of 54-96 Ma. They mostly are low-grade uranium deposits, and of hydrothermal-regeneration origin with the uranium source derived from the mobilization of consolidated rocks. The early-stage uranium deposits should be the main target of further prospecting for high-grade uranium deposits in the region

  1. Numerical Study of the Formation, Ion Spin-up and Nonlinear Stability Properties of Field-reversed Configurations

    International Nuclear Information System (INIS)

    Belova, E.V.; Davidson, R.C.; Ji, H.; Yamada, M.; Cothran, C.D.; Brown, M.R.; Schaffer, M.J.

    2004-01-01

    Results of three-dimensional numerical simulations of field-reversed configurations (FRCs) are presented. Emphasis of this work is on the nonlinear evolution of magnetohydrodynamic (MHD) instabilities in kinetic FRCs and the new FRC formation method by the counter-helicity spheromak merging. Kinetic simulations show nonlinear saturation of the n = 1 tilt mode, where n is the toroidal mode number. The n = 2 and n = 3 rotational modes are observed to grow during the nonlinear phase of the tilt instability due to the ion spin-up in the toroidal direction. The ion toroidal spin-up is shown to be related to the resistive decay of the internal flux, and the resulting loss of particle confinement. Three-dimensional MHD simulations of counter-helicity spheromak merging and FRC formation show good agreement with results from the SSX-FRC experiment. Simulations show formation of an FRC in about 30 Alfven times for typical experimental parameters. The growth rate of the n = 1 tilt mode is shown to be significantly reduced compared to the MHD growth rate due to the large plasma viscosity and field-line-tying effects

  2. Formation of photoluminescent n-type macroporous silicon: Effect of magnetic field and lateral electric potential

    Energy Technology Data Exchange (ETDEWEB)

    Antunez, E.E. [Centro de Investigación en Ingeniería y Ciencias Aplicadas, UAEM, Av. Universidad 1001, Col. Chamilpa, Cuernavaca, Morelos, CP 62210 (Mexico); Estevez, J.O. [Instituto de Física, B. Universidad Autónoma de Puebla, A.P. J-48, Puebla 72570 (Mexico); Campos, J. [Instituto de Energías Renovables, UNAM, Priv. Xochicalco S/N, Temixco, Morelos, CP 62580 (Mexico); Basurto-Pensado, M.A. [Centro de Investigación en Ingeniería y Ciencias Aplicadas, UAEM, Av. Universidad 1001, Col. Chamilpa, Cuernavaca, Morelos, CP 62210 (Mexico); Agarwal, V., E-mail: vagarwal@uaem.mx [Centro de Investigación en Ingeniería y Ciencias Aplicadas, UAEM, Av. Universidad 1001, Col. Chamilpa, Cuernavaca, Morelos, CP 62210 (Mexico)

    2014-11-15

    Metal electrode-free electrochemical etching of low doped n-type silicon substrates, under the combined effect of magnetic and lateral electric field, is used to fabricate photoluminescent n-type porous silicon structures in dark conditions. A lateral gradient in terms of structural characteristics (i.e. thickness and pore dimensions) along the electric field direction is formed. Enhancement of electric and magnetic field resulted in the increase of pore density and a change in the shape of the macropore structure, from circular to square morphology. Broad photoluminescence (PL) emission from 500 to 800 nm, with a PL peak wavelength ranging from 571 to 642 nm, is attributed to the wide range of microporous features present on the porous silicon layer.

  3. Filament formation in wind-cloud interactions- II. Clouds with turbulent density, velocity, and magnetic fields

    Science.gov (United States)

    Banda-Barragán, W. E.; Federrath, C.; Crocker, R. M.; Bicknell, G. V.

    2018-01-01

    We present a set of numerical experiments designed to systematically investigate how turbulence and magnetic fields influence the morphology, energetics, and dynamics of filaments produced in wind-cloud interactions. We cover 3D, magnetohydrodynamic systems of supersonic winds impacting clouds with turbulent density, velocity, and magnetic fields. We find that lognormal density distributions aid shock propagation through clouds, increasing their velocity dispersion and producing filaments with expanded cross-sections and highly magnetized knots and subfilaments. In self-consistently turbulent scenarios, the ratio of filament to initial cloud magnetic energy densities is ∼1. The effect of Gaussian velocity fields is bound to the turbulence Mach number: Supersonic velocities trigger a rapid cloud expansion; subsonic velocities only have a minor impact. The role of turbulent magnetic fields depends on their tension and is similar to the effect of radiative losses: the stronger the magnetic field or the softer the gas equation of state, the greater the magnetic shielding at wind-filament interfaces and the suppression of Kelvin-Helmholtz instabilities. Overall, we show that including turbulence and magnetic fields is crucial to understanding cold gas entrainment in multiphase winds. While cloud porosity and supersonic turbulence enhance the acceleration of clouds, magnetic shielding protects them from ablation and causes Rayleigh-Taylor-driven subfilamentation. Wind-swept clouds in turbulent models reach distances ∼15-20 times their core radius and acquire bulk speeds ∼0.3-0.4 of the wind speed in one cloud-crushing time, which are three times larger than in non-turbulent models. In all simulations, the ratio of turbulent magnetic to kinetic energy densities asymptotes at ∼0.1-0.4, and convergence of all relevant dynamical properties requires at least 64 cells per cloud radius.

  4. Wave-Field Formation in a Hollow X-Ray Waveguide

    International Nuclear Information System (INIS)

    Bukreeva, I.; Popov, A.; Pelliccia, D.; Cedola, A.; Lagomarsino, S.; Dabagov, S. B.

    2006-01-01

    Diffraction and refraction phenomena at the entrance of a hollow x-ray waveguide with weakly absorbing dielectric cladding layers are investigated using two independent approaches: (a) analytical and (b) numerical solutions of the wave equation in the paraxial (parabolic) approximation. It is shown that the wave penetrating through the cladding material substantially modifies the wave field near the waveguide entrance. It results in a significant increase of the total energy flux inside the guiding layer and in additional spatial modulation of the electromagnetic field

  5. A disulfide-linked amyloid-beta peptide dimer forms a protofibril-like oligomer through a distinct pathway from amyloid fibril formation.

    Science.gov (United States)

    Yamaguchi, Takahiro; Yagi, Hisashi; Goto, Yuji; Matsuzaki, Katsumi; Hoshino, Masaru

    2010-08-24

    The conversion of the soluble, nontoxic amyloid-beta (Abeta) peptide into an aggregated, toxic form rich in beta-sheets is considered a key step in the development of Alzheimer's disease. Whereas growing evidence indicates that the Abeta amyloid fibrils consist of in-register parallel beta-sheets, little is known about the structure of soluble oligomeric intermediates because of their transient nature. To understand the mechanism by which amyloid fibrils form, especially the initial development of the "nucleus" oligomeric intermediates, we prepared covalently linked dimeric Abeta peptides and analyzed the kinetics of the fibril-forming process. A covalent bond introduced between two Abeta molecules dramatically facilitated the spontaneous formation of aggregates with a beta-sheet structure and affinity for thioflavin T. Transmission electron microscopy revealed, however, that these aggregates differed in morphology from amyloid fibrils, more closely resembling protofibrils. The protofibril-like aggregates were not the most thermodynamically stable state but were a kinetically trapped state. The results emphasize the importance of the conformational flexibility of the Abeta molecule and a balance in the association and dissociation rate for the formation of rigid amyloid fibrils.

  6. The Great Solar Active Region NOAA 12192: Helicity Transport, Filament Formation, and Impact on the Polar Field

    Science.gov (United States)

    Petrie, Gordon; McMaken, Tyler C.

    2017-08-01

    The solar active region (AR), NOAA 12192, appeared in 2014 October as the largest AR in 24 years. Here we examine the counterintuitive nature of two diffusion-driven processes in the region: the role of helicity buildup in the formation of a major filament, and the relationship between the effects of supergranular diffusion and meridional flow on the AR and on the polar field. Quantitatively, calculations of current helicity and magnetic twist from Helioseismic and Magnetic Imager (HMI) vector magnetograms indicate that, though AR 12192 emerged with negative helicity, positive helicity from subsequent flux emergence, consistent with the hemispheric sign-preference of helicity, increased over time within large-scale, weak-field regions such as those near the polarity inversion line (PIL). Morphologically, Atmospheric Imaging Assembly observations of filament barbs, sigmoidal patterns, and bases of Fe xii stalks initially exhibited signatures of negative helicity, and the long filament that subsequently formed had a strong positive helicity consistent with the helicity buildup along the PIL. We find from full-disk HMI magnetograms that AR 12192's leading positive flux was initially closer to the equator but, owing either to the region’s magnetic surroundings or to its asymmetric flux density distribution, was transported poleward more quickly on average than its trailing negative flux, contrary to the canonical pattern of bipole flux transport. This behavior caused the AR to have a smaller effect on the polar fields than expected and enabled the formation of the very long neutral line where the filament formed.

  7. Formation of edge transport barrier in the ergodic field layer of helical divertor configuration on the Large Helical Device

    International Nuclear Information System (INIS)

    Toi, K; Ohdachi, S; Watanabe, F; Narihara, K; Morisaki, T; Sakakibara, S; Morita, S; Goto, M; Ida, K; Masuzaki, S; Miyazawa, K; Tanaka, K; Tokuzawa, T; Watanabe, K W; Yoshinuma, M

    2006-01-01

    On the Large Helical Device (LHD), low to high confinement (L-H) transition and edge transport barrier (ETB) formation were observed in the low beta regime ((β dia ) dia ): volume-averaged beta derived from diamagnetic measurement) as well as in relatively high beta regime (>1.5%). In most of ETB plasmas electron density preferentially increases in the edge region without a substantial rise of the edge electron temperature. The ETB zone develops inside the ergodic field layer calculated in the vacuum field. The ETB formation strongly destabilizes edge coherent modes such as m/n = 2/3 or 1/2 (m, n: poloidal and toroidal mode numbers), because the plasma edge region is in the magnetic hill. The ETB is partially destroyed by the combination of these edge MHD modes and ELM-like activities. For a particular experimental condition, the forced generation of a sizable m/n = 1/1 magnetic island near the edge by application of external field perturbations facilitates the L-H transition at a lower electron density and suppresses edge MHD modes and ELM-like activities to lower levels

  8. Approaches to identifying reservoir heterogeneity and reserve growth opportunities from subsurface data: The Oficina Formation, Budare field, Venezuela

    Energy Technology Data Exchange (ETDEWEB)

    Hamilton, D.S.; Raeuchle, S.K.; Holtz, M.H. [Bureau of Economic Geology, Austin, TX (United States)] [and others

    1997-08-01

    We applied an integrated geologic, geophysical, and engineering approach devised to identify heterogeneities in the subsurface that might lead to reserve growth opportunities in our analysis of the Oficina Formation at Budare field, Venezuela. The approach involves 4 key steps: (1) Determine geologic reservoir architecture; (2) Investigate trends in reservoir fluid flow; (3) Integrate fluid flow trends with reservoir architecture; and (4) Estimate original oil-in-place, residual oil saturation, and remaining mobile oil, to identify opportunities for reserve growth. There are three main oil-producing reservoirs in the Oficina Formation that were deposited in a bed-load fluvial system, an incised valley-fill, and a barrier-strandplain system. Reservoir continuity is complex because, in addition to lateral facies variability, the major Oficina depositional systems were internally subdivided by high-frequency stratigraphic surfaces. These surfaces define times of intermittent lacustrine and marine flooding events that punctuated the fluvial and marginal marine sedimentation, respectively. Syn and post depositional faulting further disrupted reservoir continuity. Trends in fluid flow established from initial fluid levels, response to recompletion workovers, and pressure depletion data demonstrated barriers to lateral and vertical fluid flow caused by a combination of reservoir facies pinchout, flooding shale markers, and the faults. Considerable reserve growth potential exists at Budare field because the reservoir units are highly compartment by the depositional heterogeneity and structural complexity. Numerous reserve growth opportunities were identified in attics updip of existing production, in untapped or incompletely drained compartments, and in field extensions.

  9. Experimental study of the initial plasma formation stage in a linear theta pinch of inverted field

    International Nuclear Information System (INIS)

    Casin, G.C.; Alvarez, Ricardo; Rojkind, R.H.; Rodrigo, A.B.

    1986-01-01

    The initial stage of the plasma formation was studied in a linear theta pinch. Experiments were made to determine the machine operating conditions for good shot-to-shot reproducibility. Spectroscopic measurements of electron density and of electron and ion temperature were made afterwards to characterize the plasma at different stages of its heating process. The results obtained indicate that shot-to-shot reproducibility is strongly influenced by the presence of impurities and by the plasma preionization technique used. Under proper operating conditions, excellent reproducibility was observed. The measured values of the plasma parameters are compatible with those determined for similar machines. (Author) [es

  10. Polarized Line Formation in Arbitrary Strength Magnetic Fields Angle-averaged and Angle-dependent Partial Frequency Redistribution

    Energy Technology Data Exchange (ETDEWEB)

    Sampoorna, M.; Nagendra, K. N. [Indian Institute of Astrophysics, Koramangala, Bengaluru 560 034 (India); Stenflo, J. O., E-mail: sampoorna@iiap.res.in, E-mail: knn@iiap.res.in, E-mail: stenflo@astro.phys.ethz.ch [Institute of Astronomy, ETH Zurich, CH-8093 Zurich (Switzerland)

    2017-08-01

    Magnetic fields in the solar atmosphere leave their fingerprints in the polarized spectrum of the Sun via the Hanle and Zeeman effects. While the Hanle and Zeeman effects dominate, respectively, in the weak and strong field regimes, both these effects jointly operate in the intermediate field strength regime. Therefore, it is necessary to solve the polarized line transfer equation, including the combined influence of Hanle and Zeeman effects. Furthermore, it is required to take into account the effects of partial frequency redistribution (PRD) in scattering when dealing with strong chromospheric lines with broad damping wings. In this paper, we present a numerical method to solve the problem of polarized PRD line formation in magnetic fields of arbitrary strength and orientation. This numerical method is based on the concept of operator perturbation. For our studies, we consider a two-level atom model without hyperfine structure and lower-level polarization. We compare the PRD idealization of angle-averaged Hanle–Zeeman redistribution matrices with the full treatment of angle-dependent PRD, to indicate when the idealized treatment is inadequate and what kind of polarization effects are specific to angle-dependent PRD. Because the angle-dependent treatment is presently computationally prohibitive when applied to realistic model atmospheres, we present the computed emergent Stokes profiles for a range of magnetic fields, with the assumption of an isothermal one-dimensional medium.

  11. Field measurements of key parameters associated with nocturnal OBT formation in vegetables grown under Canadian conditions

    International Nuclear Information System (INIS)

    Kim, S.B.; Workman, W.G.; Korolevych, V.; Davis, P.A.

    2012-01-01

    The objective of this study was to provide the parameter values required to model OBT formation in the edible parts of plants following a hypothetical accidental tritium release to the atmosphere at night. The parameters considered were leaf area index, stomatal resistance, photosynthesis rate, the photosynthetic production rate of starch, the nocturnal hydrolysis rate of starch, the fraction of starch produced daily by photosynthesis that appears in the fruits, and the mass of the fruit. Values of these parameters were obtained in the summer of 2002 for lettuce, radishes and tomatoes grown under typical Canadian environmental conditions. Based on the maximum observed photosynthetic rate and growth rate, the fraction of starch translocated to the fruit was calculated to be 17% for tomato fruit and 14% for radish root. - Highlights: ► Plant physiological parameters affecting nocturnal OBT formation have been investigated. ► The fraction of starch produced daily by photosynthesis in the leaves that appears in the fruit was calculated. ► Realistic estimates of OBT concentrations following a nighttime accidental HTO release to the atmosphere.

  12. Method of formation of a high gradient magnetic field and the device for division of substances

    International Nuclear Information System (INIS)

    Il'yashenko, E. I.; Glebov, V. A.; Skeltorp, A. T.

    2005-01-01

    Full text: The method and the device [1] are intended for use as a high-sensitivity magnetic separator for different types of paramagnetic substances and materials from diamagnetic ones, for division of paramagnetic substances and materials on the magnitudes of their paramagnetic susceptibility, for division of diamagnetic substances and materials on magnitudes of their diamagnetic susceptibility. Scopes: to produce pure and super pure substances and materials in electronics, metallurgy and chemistry, separation of biological objects (red blood cells, magnetic bacteria, etc.) in biology and medicine, water treatment removing heavy metals and organic impurities, etc. The main condition for magnetic separation is the magnetic force which acts on a particle of the substance and which is proportional to the magnetic susceptibility of the substance, magnetic induction B and gradient ∇B of the applied magnetic field. Therefore, to increase the sensitivity and selectivity of magnetic separation it will be required to use the largest possible values of the magnetic induction and the gradient of a magnetic field, or their product - B∇B. The device declared in the present work includes the magnetic system such as the open domain structure, consisting of permanent magnets with magnetic anisotropy much greater than the induction of a material of magnets. However, the declared device differs from the open domain structure in that [1]: *the surface of the neighbor poles of magnets is covered with a mask made from sheets of adjustable thickness of a soft magnetic material; *the soft magnetic material of the mask is selected on the basis of the magnitudes of the induction of saturation and magnetic permeability for achievement of the required magnitude of the induction and gradient of the magnetic field; *between the sheets of the mask there is an adjustable gap located symmetrically relative to the junction line of the magnets; *the size and the form of the gap between the

  13. Field Transmission of 8 × 170 Gb/s Over High-Loss SSMF Link Using Third-Order Distributed Raman Amplification

    Science.gov (United States)

    Schneiders, Malte; Vorbeck, Sascha; Leppla, Ralph; Lach, Eugen; Schmidt, Michael; Papernyi, Serguei B.; Sanapi, Kris

    2006-01-01

    This paper reports on the field transmission of N × 170-Gb/s over high-loss fiber links using third-order distributed Raman amplification (DRA) in a commercially operated network of Deutsche Telekom. It gives an overview of the key technologies applied for the realization of an 8 × 170 Gb/s (1.28 Tb/s) dense wavelength division multiplexing (DWDM) system demonstrator and summarizes long-haul transmission experiments with terabit-per-second capacity over European fiber infrastructure. Third-order DRA enabled repeaterless transmission of 1 × 170 Gb/s and 8 × 170 Gb/s over links of 185-and 140-km field fiber, respectively. Including an additional 25 km of lumped standard single-mode fiber (SSMF) at the end of the span, a total loss of 61 and 44 dB, respectively, was bridged.

  14. Near-Field Inductive-Coupling Link to Power a Three-Dimensional Millimeter-Size Antenna for Brain Implantable Medical Devices.

    Science.gov (United States)

    Manoufali, Mohamed; Bialkowski, Konstanty; Mohammed, Beadaa Jasem; Mills, Paul C; Abbosh, Amin

    2018-01-01

    Near-field inductive-coupling link can establish a reliable power source to a batteryless implantable medical device based on Faraday's law of induction. In this paper, the design, modeling, and experimental verification of an inductive-coupling link between an off-body loop antenna and a 0.9  three-dimensional (3-D) bowtie brain implantable antenna is presented. To ensure reliability of the design, the implantable antenna is embedded in the cerebral spinal fluid of a realistic human head model. Exposure, temperature, and propagation simulations of the near electromagnetic fields in a frequency-dispersive head model were carried out to comply with the IEEE safety standards. Concertedly, a fabrication process for the implantable antenna is proposed, which can be extended to devise and miniaturize different 3-D geometric shapes. The performance of the proposed inductive link was tested in a biological environment; in vitro measurements of the fabricated prototypes were carried in a pig's head and piglet. The measurements of the link gain demonstrated   in the pig's head and   in piglet. The in vitro measurement results showed that the proposed 3-D implantable antenna is suitable for integration with a miniaturized batteryless brain implantable medical device (BIMD).

  15. [Essence, goals, formation of information field and general methodology of the development of a business plan for stomatology institutions].

    Science.gov (United States)

    Kamalov, R Kh; Pavlovskiĭ, L N

    2005-12-01

    A private stomatology clinics (institution) can not operate in market system of management with benefit without clear guiding lines and a real business plan. Entrepreneurs meet many different issues during organizing stomatology business, as follows: what categories of population will address to the clinics, what financial resources an entrepreneur we need to realize a project, does the project justify itself economically etc? A business plan is created to answer the questions mentioned above. The article considers essence, goals, formation of information field and general methodology of the development of a business plan for stomatology institutions.

  16. Ambipolar field role in formation of electron distribution function in gas discharge plasma.

    Science.gov (United States)

    Yuan, Chengxun; Bogdanov, E A; Kudryavtsev, A A; Rabadanov, K M; Zhou, Zhongxiang

    2017-11-06

    It is shown that the local approximation for electron distribution function (EDF) determination at plasma periphery, where the ambipolar field is dominant, is not applicable even at high pressures when the characteristic plasma size exceeds the energy relaxation length of the electrons R > λ ε . Therefore, consistent results can be obtained only when solving the complete kinetic equation in both energy and spatial variables (i.e. it is necessary to solve nonlocal kinetic equation).

  17. Motions of CMS Detector structures due to the magnetic field forces as observed by the Link Alignment System during the Test of the 4 Tesla Magnet Solenoid

    CERN Document Server

    Calderón, Alicia; González-Sánchez, F J; Martínez-Rivero, C; Matorras, Francisco; Rodrigo, Teresa; Martínez, P; Scodellaro, Luca; Sobrón, M; Vila, Ivan; Virto, A L; Alberdi, Javier; Arce, Pedro; Barcala, Jose Miguel; Calvo, Enrique; Ferrando, Antonio; Josa-Mutuberria, I; Molinero, Antonio; Navarrete, Jose Javier; Oller, Juan Carlos; Yuste, Ceferino

    2008-01-01

    This document describes results obtained from the Link Alignment System data recorded during the CMS Magnet Test. A brief description of the system is followed by the discussion of the detected relative displacements (from micrometres to centimetres) between detector elements and rotations of detector structures (from microradians to milliradians). Observed displacements are studied as functions of the magnetic field intensity. In addition, the reconstructed positions of active element sensors are compared to their positions as measured by photogrammetry and the reconstructed motions due to the magnetic field strength are described.

  18. Motions of CMS detector structures due to the magnetic field forces as observed by the Link alignment system during the test of the 4 T magnet solenoid

    International Nuclear Information System (INIS)

    Garcia-Moral, L.A.; Gomez, G.; Gonzalez-Sanchez, F.J.; Martinez-Rivero, C.; Matorras, F.; Rodrigo, T.; Martinez, P.; Scodellaro, L.; Vila, I.; Virto, A.L.; Sobron, M.; Alberdi, J.; Arce, P.; Barcala, J.M.; Calvo, E.; Ferrando, A.; Josa, M.I.; Molinero, A.; Navarrete, J.; Oller, J.C.

    2009-01-01

    This document describes results obtained from the Link alignment system data recorded during the Compact Muon Solenoid (CMS) Magnet Test. A brief description of the system is followed by a discussion of the detected relative displacements (from micrometres to centimetres) between detector elements and rotations of detector structures (from microradians to milliradians). Observed displacements are studied as functions of the magnetic field intensity. In addition, the reconstructed positions of active element sensors are compared to their positions as measured by photogrammetry and the reconstructed motions due to the magnetic field strength are described.

  19. Strategies for the formation of human resources in the mexican nuclear field

    International Nuclear Information System (INIS)

    Gomez T, A.M.; Valle G, E. del; Francois L, J.L.; Espinosa P, G.; Mireles G, F.; Croche B, R.; Lartigue G, J.

    2007-01-01

    This work looks for to put in the discussion table the topic of the formation of human resources highly qualified that doubtless will need the country in the short term, same that will have to begin to be formed from now on to be able to satisfy the demand in the next future. They take like base several studies carried out by the NEA/OECD and the recommendations that have emanated of the same ones for later to make an approach of the current Mexican situation and to conclude with a series of recommendations that have been identified. The recommendations here exposed, they are only the thought of the authors and in no way they are based on an already carried out study. However it will be important to open the debate on the real strategies to have a national nuclear politics based on solid resultant foundations of the production and training of brilliant human resources. (Author)

  20. The Star Formation Main Sequence in the Hubble Space Telescope Frontier Fields

    Science.gov (United States)

    Santini, Paola; Fontana, Adriano; Castellano, Marco; Di Criscienzo, Marcella; Merlin, Emiliano; Amorin, Ricardo; Cullen, Fergus; Daddi, Emanuele; Dickinson, Mark; Dunlop, James S.; Grazian, Andrea; Lamastra, Alessandra; McLure, Ross J.; Michałowski, Michał. J.; Pentericci, Laura; Shu, Xinwen

    2017-09-01

    We investigate the relation between star formation rate (SFR) and stellar mass (M), I.e., the main sequence (MS) relation of star-forming galaxies, at 1.3≤slant zframe UV observations. Gravitational lensing combined with deep HST observations allows us to extend the analysis of the MS down to {log} M/{M}⊙ ˜ 7.5 at z≲ 4 and {log} M/{M}⊙ ˜ 8 at higher redshifts, a factor of ˜10 below most previous results. We perform an accurate simulation to take into account the effect of observational uncertainties and correct for the Eddington bias. This step allows us to reliably measure the MS and in particular its slope. While the normalization increases with redshift, we fit an unevolving and approximately linear slope. We nicely extend to lower masses the results of brighter surveys. Thanks to the large dynamic range in mass and by making use of the simulation, we analyzed any possible mass dependence of the dispersion around the MS. We find tentative evidence that the scatter decreases with increasing mass, suggesting a larger variety of star formation histories in low-mass galaxies. This trend agrees with theoretical predictions and is explained as either a consequence of the smaller number of progenitors of low-mass galaxies in a hierarchical scenario and/or of the efficient but intermittent stellar feedback processes in low-mass halos. Finally, we observe an increase in the SFR per unit stellar mass with redshift milder than predicted by theoretical models, implying a still incomplete understanding of the processes responsible for galaxy growth.

  1. Near-field shock formation in noise propagation from a high-power jet aircraft.

    Science.gov (United States)

    Gee, Kent L; Neilsen, Tracianne B; Downing, J Micah; James, Michael M; McKinley, Richard L; McKinley, Robert C; Wall, Alan T

    2013-02-01

    Noise measurements near the F-35A Joint Strike Fighter at military power are analyzed via spatial maps of overall and band pressure levels and skewness. Relative constancy of the pressure waveform skewness reveals that waveform asymmetry, characteristic of supersonic jets, is a source phenomenon originating farther upstream than the maximum overall level. Conversely, growth of the skewness of the time derivative with distance indicates that acoustic shocks largely form through the course of near-field propagation and are not generated explicitly by a source mechanism. These results potentially counter previous arguments that jet "crackle" is a source phenomenon.

  2. A Field Experiment on Search Costs and the Formation of Scientific Collaborations.

    Science.gov (United States)

    Boudreau, Kevin J; Brady, Tom; Ganguli, Ina; Gaule, Patrick; Guinan, Eva; Hollenberg, Anthony; Lakhani, Karim R

    2017-10-01

    We present the results of a field experiment conducted at Harvard Medical School to understand the extent to which search costs affect matching among scientific collaborators. We generated exogenous variation in search costs for pairs of potential collaborators by randomly assigning individuals to 90-minute structured information-sharing sessions as part of a grant funding opportunity. We estimate that the treatment increases the probability of grant co-application of a given pair of researchers by 75%. The findings suggest that matching between scientists is subject to considerable frictions, even in the case of geographically-proximate scientists working in the same institutional context.

  3. Multiple layers of self-asssembled Ge/Si islands: Photoluminescence, strain fields, material interdiffusion, and island formation

    International Nuclear Information System (INIS)

    Schmidt, O.G.; Eberl, K.

    2000-01-01

    Strain fields in stacked layers of vertically aligned self-assembled Ge islands on Si(100) can cause a reduction of the wetting layer thickness in all but the initial layer and hence induce an energy separation ΔE wl between the energy transitions of the different wetting layers. Our systematic photoluminescence (PL) study on twofold stacked Ge/Si layers shows that the quantity ΔE wl is a sensitive function of the Si spacer thickness and reflects the degree of strain field interaction between the island layers. Pronounced PL blueshifts are also observed for the island related energy transition in twofold and multifold island layers. We suggest that with increasing number of stacked island layers strain field superposition of buried islands causes enhanced SiGe material intermixing during Si overgrowth of the islands. This effect naturally explains the strong PL blueshift of the island related energy transition. Recently observed shape transformations in stacked Ge islands are well explained by our model of superimposed strain fields. We also discuss the initial stages of island formation in the second Ge layer of twofold island stacks. Many of the effects observed in this paper on the Ge/Si system are probably also important for self-assembling III/V islands but due to extremely small sizes are much harder to evaluate

  4. Current sheet formation in a sheared force-free-magnetic field. [in sun

    Science.gov (United States)

    Wolfson, Richard

    1989-01-01

    This paper presents the results of a study showing how continuous shearing motion of magnetic footpoints in a tenuous, infinitely conducting plasma can lead to the development of current sheets, despite the absence of such sheets or even of neutral points in the initial state. The calculations discussed here verify the earlier suggestion by Low and Wolfson (1988) that extended current sheets should form due to the shearing of a force-free quadrupolar magnetic field. More generally, this work augments earlier studies suggesting that the appearance of discontinuities - current sheets - may be a necessary consequence of the topological invariance imposed on the magnetic field geometry of an ideal MHD system by virtue of its infinite conductivity. In the context of solar physics, the work shows how the gradual and continuous motion of magnetic footpoints at the solar photosphere may lead to the buildup of magnetic energy that can then be released explosively when finite conductivity effects become important and lead to the rapid dissipation of current sheets. Such energy release may be important in solar flares, coronal mass ejections, and other eruptive events.

  5. A new experimental method to prevent paraffin - wax formation on the crude oil wells: A field case study in Libya

    Directory of Open Access Journals (Sweden)

    Elhaddad Elnori E.

    2015-01-01

    Full Text Available Wax formation and deposition is one of the most common problems in oil producing wells. This problem occurs as a result of the reduction of the produced fluid temperature below the wax appearance temperature (range between 46°C and 50°C and the pour point temperature (range between 42°C and 44°C. In this study, two new methods for preventing wax formation were implemented on three oil wells in Libya, where the surface temperature is, normally, 29°C. In the first method, the gas was injected at a pressure of 83.3 bar and a temperature of 65°C (greater than the pour point temperature during the gas-lift operation. In the second method, wax inhibitors (Trichloroethylene-xylene (TEX, Ethylene copolymers, and Comb polymers were injected down the casings together with the gas. Field observations confirmed that by applying these techniques, the production string was kept clean and no wax was formed. The obtained results show that the wax formation could be prevented by both methods.

  6. Depositional features of the Middle Jurassic formation of Field N and their influence on optimal drilling schedule

    Science.gov (United States)

    Mishina, D.; Rukavishnikov, V.; Belozerov, B.; Bochkov, A.

    2015-02-01

    The Middle Jurassic formation of Field N represented by 4 hydrodynamically connected layers (J5-6, J4, J3 and J2) contains 42% of the field STOIIP. The J2-6 formation is characterized as a gas-oil-condensate massive lithologically and tectonically screened accumulation with a gas cap (J2, J3 layers) and bottom water (J5-6 layer). Oil is predominantly in the J3 and J4 layers. There is a high risk of early gas coning from gas-bearing layers to oil producing wells determined on the basis of production test results, which can significantly decrease the life of the well. To select a more optimal drilling schedule, it is necessary to take the risk of early gas coning into account and determine distinctive features within the gas- saturated zone that can reduce it. The presence of a thick shale barrier between the J2 and J3 layers with thicknesses varying from 0 to 30 m is recognized as the beginning of a transgression cycle, and if the gas cap is only in the J2 layer, this barrier with the thickness of more than 5 m can extensively prevent early gas coning into oil producing wells. The integration of geological information represented by the probability map constructed and petrophysical information represented by the kh map provide the more precise determination of an optimal drilling schedule.

  7. Shock-front compression of the magnetic field in the Canis Majoris R1 star-formation region

    International Nuclear Information System (INIS)

    Vrba, F.J.; Baierlein, R.; Herbst, W.; Wesleyan Univ., Middletown, CT; Van Vleck Observatory, Middletown, CT)

    1987-01-01

    Results are presented from a linear polarization survey at optical wavelengths of over 140 stars in the direction of the CMa R1 star-formation region; 26 of these are clearly associated with nebulosity within the area. The observations were obtained in order to test the argument of Herbst et al. (1978) that star formation in CMa R1 is driven by a shock wave from a nearby supernova (Herbs and Assousa, 1977 and 1978). The polarizations are found to be consistent with a simple model of the compression by a supernova-induced spherical shock front of an initially uniform interstellar magnetic field. The polarization vectors are inconsistent with a scenario of quiescent cloud collapse along magnetic-field lines. Multicolor polarimetry of the nebular stars provides evidence of grain growth toward increasing cloud optical depth, characterized by a ratio of total-to-selective extinction of R = 3.0 at E(B-V) = 0.23, increasing to R = 4.2 at E(B-V) = 0.7. 15 references

  8. Indications of field-directing and self-templating effects on the formation of organic lines on silicon.

    Science.gov (United States)

    Zikovsky, Janik; Dogel, Stanislav A; Salomons, Mark H; Pitters, Jason L; DiLabio, Gino A; Wolkow, Robert A

    2011-03-21

    It has previously been shown that multimolecular organic nanostructures form on H-Si(100)-2×1 via a radical mediated growth process. In this mechanism, growth begins through the addition of a molecule to a silicon surface dangling bond, followed by the abstraction of a neighboring H atom and generation of a new dangling bond on the neighboring site. Nanostructures formed by this mechanism grow along one edge of a dimer row. Here, we explored the possibility of using lithographically prepared, biased metal contacts on the silicon surface to generate an electric field that orients molecules during the growth process to achieve growth in the perpendicular-to-row direction. The formation of some nanostructures in a direction that was nearly perpendicular to the dimer rows was achieved, whereas such features were not formed in the absence of the field. Analysis of the scanning tunneling microscopy images suggests that the formation of these nanostructures may involve self-templating effects in addition to dangling bond diffusion rather than a straightforward addition∕abstraction mechanism. These initial results offer some indication that a molecular pattern writer can be achieved.

  9. Hydrogeochemistry of the formation waters in the San Francisco field, UMV basin, Colombia - A multivariate statistical approach

    Science.gov (United States)

    Cortes, J. E.; Muñoz, L. F.; Gonzalez, C. A.; Niño, J. E.; Polo, A.; Suspes, A.; Siachoque, S. C.; Hernández, A.; Trujillo, H.

    2016-08-01

    A wide variety of hydrogeochemical data were obtained through the analysis of the formation water samples collected from 118 producing wells from the San Francisco Oilfield (SFO) in the Upper Magdalena Valley (UMV) basin, Huila, Colombia. The study area is composed of deposited sandstone in fluvial-lacustrine marine environment, which characterized the formation waters as chloride-sodium water type. The brackish-saline facies identified can be attributed to evaporation, halite and dolomite dissolution along with water recharge of meteoric waters somewhere in the basin, probably from Magdalena River, the contribution of the SFO injection water system and significantly by the rock-water interaction. Some ionic ratios were used to confirm clearly that water-rock interactions play a significant role in the evolution of the hydrogeochemistry process in the SFO. The charge balance error ranges between -5.88% and 2.62% indicating very well balanced and mature water for blocks 1, 2 and 3 (north part of the field), and partially equilibrated and immature waters for blocks 4, 5, 6, 7, and 8 as is confirmed by Piper, Giggenbach, and Schöeller diagrams. Calculated scale and stability indices (Langelier, Ryznar, and Puckorius), besides halite and dolomite indexes, indicate that these formation waters are slightly saturated with respect to the calcite and dolomite and have strong tendency to the scale formation as well. Concentration maps were used to identify the geological factors that could have influenced its chemical composition and the hydrogeochemical processes involved in the field, such as halite dissolution, calcite or dolomite precipitation and cationic exchange reactions. The mineralogical distribution leads to the conclusion that the halite dissolution is mostly distributed in the Northeastern area of the SFO between B1, B3, B4, B5, and B6 blocks, the dolomite and calcite have greater concentrations between B5 and B6 blocks. The dissolved minerals followed the

  10. Polyhedra Formation and Transient Cone Ejection of a Resonant Microdrop Forced by an ac Electric Field

    Science.gov (United States)

    Wang, Ping; Maheshwari, Siddharth; Chang, Hsueh-Chia

    2006-06-01

    New deformation or fission phenomena are reported for microdrops driven by an ac electric field at their resonant frequencies. The Maxwell forces that pull out the vertices from a drop can be enhanced when the ac frequency is comparable to both the drop resonant frequency and the inverse charge relaxation time of the diffuse layer. The selected polyhedra possess symmetries that ensure a global force balance of the Maxwell forces and a linear dimension consistent with a sphere whose nth harmonic (n is up to six in the observation) coincides with the applied ac frequency. At high voltages, the resonant focusing of charges by the vibration modes produces evenly distributed and transient Taylor cones that can eject charged nanodrops.

  11. Weak interactions from 1950-1960: a quantitative bibliometric study of the formation of a field

    International Nuclear Information System (INIS)

    White, D.H.; Sullivan, D.

    1986-01-01

    A quantitative technique is illustrated which uses publication statistics from a bibliography of citations in the area of weak interactions to provide a view of trends and patterns in the development of the field during the period from 1950 to 1960. An overview is given of what the physicists working in weak interactions during this period were doing as indicated by an analysis of the subjects of their papers. The dominant problems and concerns are discussed. Focus is then turned to the events surrounding the emergence of the tau/theta particle puzzle, the discovery of parity nonconservation, and the resolution offered by the V-A theory. Displaying the data from the citation index in unusual ways highlights dominant issues of the period, especially the close relationship between theory and experiment in the latter half of the decade. 64 refs., 14 figs

  12. The Great Solar Active Region NOAA 12192: Helicity Transport, Filament Formation, and Impact on the Polar Field

    Energy Technology Data Exchange (ETDEWEB)

    McMaken, Tyler C. [National Solar Observatory REU Program, 3665 Discovery Drive, 3rd Floor, Boulder, CO 80303 (United States); Petrie, Gordon J. D., E-mail: tmcmaken@gmail.com, E-mail: gpetrie@noao.edu [National Solar Observatory, 3665 Discovery Drive, 3rd Floor, Boulder, CO 80303 (United States)

    2017-05-10

    The solar active region (AR), NOAA 12192, appeared in 2014 October as the largest AR in 24 years. Here we examine the counterintuitive nature of two diffusion-driven processes in the region: the role of helicity buildup in the formation of a major filament, and the relationship between the effects of supergranular diffusion and meridional flow on the AR and on the polar field. Quantitatively, calculations of current helicity and magnetic twist from Helioseismic and Magnetic Imager (HMI) vector magnetograms indicate that, though AR 12192 emerged with negative helicity, positive helicity from subsequent flux emergence, consistent with the hemispheric sign-preference of helicity, increased over time within large-scale, weak-field regions such as those near the polarity inversion line (PIL). Morphologically, Atmospheric Imaging Assembly observations of filament barbs, sigmoidal patterns, and bases of Fe xii stalks initially exhibited signatures of negative helicity, and the long filament that subsequently formed had a strong positive helicity consistent with the helicity buildup along the PIL. We find from full-disk HMI magnetograms that AR 12192's leading positive flux was initially closer to the equator but, owing either to the region’s magnetic surroundings or to its asymmetric flux density distribution, was transported poleward more quickly on average than its trailing negative flux, contrary to the canonical pattern of bipole flux transport. This behavior caused the AR to have a smaller effect on the polar fields than expected and enabled the formation of the very long neutral line where the filament formed.

  13. Formation and sustainment of field reversed configuration (FRC) plasmas by spheromak merging and neutral beam injection

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Masaaki [Princeton Plasma Physics Laboratory, Princeton University Princeton, New Jersey USA (United States)

    2016-03-25

    This paper briefly reviews a compact toroid reactor concept that addresses critical issues for forming, stabilizing and sustaining a field reversed configuration (FRC) with the use of plasma merging, plasma shaping, conducting shells, neutral beam injection (NBI). In this concept, an FRC plasma is generated by the merging of counter-helicity spheromaks produced by inductive discharges and sustained by the use of neutral beam injection (NBI). Plasma shaping, conducting shells, and the NBI would provide stabilization to global MHD modes. Although a specific FRC reactor design is outside the scope of the present paper, an example of a promising FRC reactor program is summarized based on the previously developed SPIRIT (Self-organized Plasmas by Induction, Reconnection and Injection Techniques) concept in order to connect this concept to the recently achieved the High Performance FRC plasmas obtained by Tri Alpha Energy [Binderbauer et al, Phys. Plasmas 22,056110, (2015)]. This paper includes a brief summary of the previous concept paper by M. Yamada et al, Plasma Fusion Res. 2, 004 (2007) and the recent experimental results from MRX.

  14. Formation of Edible Soybean and Soybean-Complex Protein Films by a Cross-Linking Treatment with a New Streptomyces Transglutaminase

    Directory of Open Access Journals (Sweden)

    Guocheng Su

    2007-01-01

    Full Text Available Soybean protein isolate (SPI was used in the investigation of the formation of edible protein films through an enzymatic cross-linking method with a purified microbial transglutaminase (MTG produced from a new effective strain Streptomyces sp. WZFF.L-M1 preserved in our laboratory, followed by the addition of glycerol and suitable heating and drying treatments. Cheaper partially-purified skimmed soybean protein powder (SSP and whey protein isolates (WPI were used as the substitutes partially replacing the expensive SPI products, and purified β-lactoglobulin was taken as the positive control of WPI. As a result, the three alternatives could also form highly efficient edible films under the optimal operation conditions. The films made with SPI alternatives, about 50 µm thin, had homogenous network structures, without any holes by direct observation with the naked eye. The tests of the properties of these films showed that they had high water-keeping capacity and strong elasticity, that the ultimate tensile strength (TS and the elongation at break (Eb had been remarkably increased (TS>5 MPa, Eb>50 %, and that the prevention rates against the permeability of water vapour and oxygen in the air were also upgraded more than 85 and 70 %, respectively.

  15. Magnetosome formation and expression of mamA, mms13, mms6 and magA in Magnetospirillum magneticum AMB-1 exposed to pulsed magnetic field.

    Science.gov (United States)

    Wang, Xiaoke; Liang, Likun; Song, Tao; Wu, Longfei

    2009-09-01

    To investigate the effects of pulsed magnetic field on magnetosome formation in Magnetospirillum magneticum AMB-1, cultures inoculated with either mangetic or non-magnetic pre-cultures were incubated under 1 mT pulsed magnetic field. Magnetism of cells was measured by using spectrophotometer coupled with applied magnetic fields and the values were described as C(mag). Magnetosome in cells was counted by transmission electron microscopy observation. The results showed that pulsed magnetic field did not affect cellular growth, but enhanced magnetosome formation. The applied pulsed magnetic field might exceed the chain of magnetosomes and change the homogeneity of the magnetosome particles. The results implied that magnetite precipitation induced by the adjacent magnetosome was affected by pulsed magnetic field. Moreover, the applied pulsed magnetic field up-regulated the magA and mamA expression in cells, which might account for the increasing number and the exceeding chain of magnetosomes in cells.

  16. BEMER Electromagnetic Field Therapy Reduces Cancer Cell Radioresistance by Enhanced ROS Formation and Induced DNA Damage.

    Science.gov (United States)

    Storch, Katja; Dickreuter, Ellen; Artati, Anna; Adamski, Jerzy; Cordes, Nils

    2016-01-01

    Each year more than 450,000 Germans are expected to be diagnosed with cancer subsequently receiving standard multimodal therapies including surgery, chemotherapy and radiotherapy. On top, molecular-targeted agents are increasingly administered. Owing to intrinsic and acquired resistance to these therapeutic approaches, both the better molecular understanding of tumor biology and the consideration of alternative and complementary therapeutic support are warranted and open up broader and novel possibilities for therapy personalization. Particularly the latter is underpinned by the increasing utilization of non-invasive complementary and alternative medicine by the population. One investigated approach is the application of low-dose electromagnetic fields (EMF) to modulate cellular processes. A particular system is the BEMER therapy as a Physical Vascular Therapy for which a normalization of the microcirculation has been demonstrated by a low-frequency, pulsed EMF pattern. Open remains whether this EMF pattern impacts on cancer cell survival upon treatment with radiotherapy, chemotherapy and the molecular-targeted agent Cetuximab inhibiting the epidermal growth factor receptor. Using more physiological, three-dimensional, matrix-based cell culture models and cancer cell lines originating from lung, head and neck, colorectal and pancreas, we show significant changes in distinct intermediates of the glycolysis and tricarboxylic acid cycle pathways and enhanced cancer cell radiosensitization associated with increased DNA double strand break numbers and higher levels of reactive oxygen species upon BEMER treatment relative to controls. Intriguingly, exposure of cells to the BEMER EMF pattern failed to result in sensitization to chemotherapy and Cetuximab. Further studies are necessary to better understand the mechanisms underlying the cellular alterations induced by the BEMER EMF pattern and to clarify the application areas for human disease.

  17. Links between soil properties and steady-state solute transport through cultivated topsoil at the field scale

    DEFF Research Database (Denmark)

    Koestel, J. K.; Norgaard, T.; Minh, Luong Nhat

    2013-01-01

    to larger water saturation and the activation of larger macropores. Our study provides further evidence that it should be possible to estimate solute transport properties from soil properties such as soil texture or bulk density. We also demonstrated that estimation approaches established for the column......It is known that solute transport through soil is heterogeneous at all spatial scales. However, little data are available to allow quantification of these heterogeneities at the field scale or larger. In this study, we investigated the spatial patterns of soil properties, hydrologic state variables......, and tracer breakthrough curves (BTCs) at the field scale for the inert solute transport under a steady-state irrigation rate which produced near-saturated conditions. Sixty-five undisturbed soil columns approximately 20 cm in height and diameter were sampled from the loamy topsoil of an agricultural field...

  18. Origin and formation of neck in a basin landform: Examples from the Camargo volcanic field, Chihuahua (México)

    Science.gov (United States)

    Aranda-Gómez, José Jorge; Housh, Todd B.; Luhr, James F.; Noyola-Medrano, Cristina; Rojas-Beltrán, Marco Antonio

    2010-11-01

    The term "neck in a basin" (NIB) landform is proposed for volcanic structures characterized by nearly circular to elliptical open basins, located near the headwater of small streams or drainages, which contain small volcanic necks and/or erosion remnants of one (or more) cinder cones. NIB landforms are typically 400-1000 m in diameter and 30-100 m deep and are invariably surrounded by steep walls cut into one or more basaltic lava flows. NIB landforms lack evidence for a primary volcanogenic origin through either collapse or youthful eruptive activity. In the Pliocene portion (4 - 2 Ma) of the Plio-Quaternary Camargo volcanic field of Chihuahua (México), they are relatively numerous and are best developed at the margins of a gently sloping (3-5°) basaltic lava plateau and near major fault scarps. Mature NIB landforms have ring-like circular drainage patterns and central elevations marked by small volcanic necks and associated radial dikes intruded into basaltic scoria-fall and /or agglutinate deposits. We interpret NIB landforms to be erosional in origin. They develop where a cinder cone is surrounded by one or more sheet-like lava flows from one or more separate subsequent vents. Once eruptive activity ceases at the younger volcano(es), fluvial erosion gradually produces a ring-like drainage pattern along the contact between the lava and the older cinder cone. As a response to a marked contrast in resistance to erosion between lava flows and unconsolidated or poorly lithified pyroclastic deposits, the older cinder cone is preferentially eroded. In this manner, a ring-shaped, steep sided erosional basin, preformed by the scoria cone, is produced; eventually fluvial erosion exposes the central neck and dikes. The volume, relief, and age of the volcanic field are key factors in the formation and preservation of a NIB landform. They form in volcanic fields where lava emissions are sufficiently vigorous to engulf earlier cinder cones. Relief and associated high rates

  19. Linking Course-Embedded Assessment Measures and Performance on the Educational Testing Service Major Field Test in Business

    Science.gov (United States)

    Barboza, Gustavo A.; Pesek, James

    2012-01-01

    Assessment of the business curriculum and its learning goals and objectives has become a major field of interest for business schools. The exploratory results of the authors' model using a sample of 173 students show robust support for the hypothesis that high marks in course-embedded assessment on business-specific analytical skills positively…

  20. Study of particle size distribution and formation mechanism of radioactive aerosols generated in high-energy neutron fields

    CERN Document Server

    Endo, A; Noguchi, H; Tanaka, S; Iida, T; Furuichi, S; Kanda, Y; Oki, Y

    2003-01-01

    The size distributions of sup 3 sup 8 Cl, sup 3 sup 9 Cl, sup 8 sup 2 Br and sup 8 sup 4 Br aerosols generated by irradiations of argon and krypton gases containing di-octyl phthalate (DOP) aerosols with 45 MeV and 65 MeV quasi-monoenergetic neutrons were measured in order to study the formation mechanism of radioactive particles in high energy radiation fields. The effects of the size distribution of the radioactive aerosols on the size of the added DOP aerosols, the energy of the neutrons and the kinds of nuclides were studied. The observed size distributions of the radioactive particles were explained by attachment of the radioactive atoms generated by the neutron-induced reactions to the DOP aerosols. (author)

  1. Volcanostratigraphic Sequences of Kebo-Butak Formation at Bayat Geological Field Complex, Central Java Province and Yogyakarta Special Province, Indonesia

    Directory of Open Access Journals (Sweden)

    Sri Mulyaningsih

    2016-06-01

    Full Text Available DOI:10.17014/ijog.3.2.77-94Bayat Complex is usually used as a work field for students of geology and other geosciences. The study area is located in the southern part of the Bayat Complex. Administratively, it belongs to Central Java Province and Yogyakarta Special Province. The lithology of Bayat is very complex, composed of various kinds of igneous, sedimentary, metamorphic, and volcanic rocks. Most of previous researchers interpreted Bayat as a melange complex constructed within a subduction zone. Kebo-Butak is one of formations that forms the Bayat field complex. The formation is composed of basalt, layers of pumice, tuff, shale, and carbonaceous tuff. Most of them are known as volcanic rocks. These imply that volcanic activities are more probable to construct the geology of Bayat rather than the subducted melange complex. The geological mapping, supported by geomorphology, petrology, stratigraphy, and geological structures, had been conducted in a comprehensive manner using the deduction-induction method. The research encounters basalt, black pumice, tuff with basaltic glasses fragments, zeolite, argilic clay, as well as feldspathic- and pumice tuff. Petrographically, the basalt is composed of labradorite, olivine, clinopyroxene, and volcanic glass. Black pumice and tuff contain prismatic clinopyroxene, granular olivine, and volcanic glasses. Feldspathic tuff and pumice tuff are crystal vitric tuff due to more abundant feldspar, quartz, and amphibole than volcanic glass. Zeolite comprises chlorite and altered glasses as deep sea altered volcanic rocks. The geologic structure is very complex, the major structures are normal faults with pyrite in it. There were two deep submarine paleovolcanoes namely Tegalrejo and Baturagung. The first paleovolcano erupted effusively producing basaltic sequence, while the second one erupted explosively ejecting feldspathic-rich pyroclastic material. The two paleovolcanoes erupted simultaneously and

  2. Field-scale forward modelling of a shallow marine carbonate ramp: the Upper Jurassic Arab Formation (onshore Abu Dhabi - UAE)

    Science.gov (United States)

    Marchionda, Elisabetta; Deschamps, Rémy; Nader, Fadi H.; Ceriani, Andrea; Di Giulio, Andrea; Lawrence, David; Morad, Daniel J.

    2017-04-01

    The stratigraphic record of a carbonate system is the result of the interplay of several local and global factors that control the physical and the biological responses within a basin. Conceptual models cannot be detailed enough to take into account all the processes that control the deposition of sediments. The evaluation of the key controlling parameters on the sedimentation can be investigated with the use of stratigraphic forward models, that permit dynamic and quantitative simulations of the sedimentary basin infill. This work focuses on an onshore Abu Dhabi field (UAE) and it aims to provide a complete picture of the stratigraphic evolution of Upper Jurassic Arab Formation (Fm.). In this study, we started with the definition of the field-scale conceptual depositional model of the Formation, resulting from facies and well log analysis based on five wells. The Arab Fm. could be defined as a shallow marine carbonate ramp, that ranges from outer ramp deposits to supratidal/evaporitic facies association (from bottom to top). With the reconstruction of the sequence stratigraphic pattern and several paleofacies maps, it was possible to suggest multiple directions of progradations at local scale. Then, a 3D forward modelling tool has been used to i) identify and quantify the controlling parameters on geometries and facies distribution of the Arab Fm.; ii) predict the stratigraphic architecture of the Arab Fm.; and iii) integrate and validate the conceptual model. Numerous constraints were set during the different simulations and sensitivity analyses were performed testing the carbonate production, eustatic oscillations and transport parameters. To verify the geological consistency the 3D forward modelling has been calibrated with the available control points (five wells) in terms of thickness and facies distribution.

  3. Phase-field modelling of microstructure formation during the solidification of continuously cast low carbon and HSLA steels

    Science.gov (United States)

    Böttger, B.; Apel, M.; Santillana, B.; Eskin, D. G.

    2012-07-01

    Cracking in continuous casting of steels has been one of the main problems for decades. Many of the cracks that occur during solidification are hot tears. To better understand the factors leading to this defect, microstructure formation is simulated for a low carbon (LCAK) and two high strength low alloyed (HSLA) steel grades during the initial stage of the process where the first solidified shell is formed inside the mould and where breakouts typically occur. 2D simulation is performed using the multiphase-field software MICRESS [1], which is coupled to the thermodynamic database TCFE6 [2] and the mobility database MOB2 [2], taking into account all elements which may have a relevant effect on the mechanical properties and structure formation during or subsequent to solidification. The use of a moving-frame boundary condition allows travelling through the entire solidification history starting from the slab surface, and tracking the morphology changes during growth of the shell. A heterogeneous nucleation model is included to permit the description of morphological transitions between the initial solidification and the subsequent columnar growth region. Furthermore, a macroscopic one-dimensional temperature solver is integrated to account for the transient and nonlinear temperature field during the initial stage of continuous casting. The external heat flux boundary conditions for this process were derived from thermal process data of the industrial slab caster. The simulation results for the three steel grades have been validated by thickness measurements of breakout shells and microstructure observation of the corresponding grades. Furthermore, the primary dendrite spacing has been measured across the whole thickness of the shell and compared with the simulated microstructures. Significant microstructure differences between the steel grades are discussed and correlated with their hot-cracking behavior.

  4. Phase-field modelling of microstructure formation during the solidification of continuously cast low carbon and HSLA steels

    International Nuclear Information System (INIS)

    Böttger, B; Apel, M; Santillana, B; Eskin, D G

    2012-01-01

    Cracking in continuous casting of steels has been one of the main problems for decades. Many of the cracks that occur during solidification are hot tears. To better understand the factors leading to this defect, microstructure formation is simulated for a low carbon (LCAK) and two high strength low alloyed (HSLA) steel grades during the initial stage of the process where the first solidified shell is formed inside the mould and where breakouts typically occur. 2D simulation is performed using the multiphase-field software MICRESS, which is coupled to the thermodynamic database TCFE6 and the mobility database MOB2, taking into account all elements which may have a relevant effect on the mechanical properties and structure formation during or subsequent to solidification. The use of a moving-frame boundary condition allows travelling through the entire solidification history starting from the slab surface, and tracking the morphology changes during growth of the shell. A heterogeneous nucleation model is included to permit the description of morphological transitions between the initial solidification and the subsequent columnar growth region. Furthermore, a macroscopic one-dimensional temperature solver is integrated to account for the transient and nonlinear temperature field during the initial stage of continuous casting. The external heat flux boundary conditions for this process were derived from thermal process data of the industrial slab caster. The simulation results for the three steel grades have been validated by thickness measurements of breakout shells and microstructure observation of the corresponding grades. Furthermore, the primary dendrite spacing has been measured across the whole thickness of the shell and compared with the simulated microstructures. Significant microstructure differences between the steel grades are discussed and correlated with their hot-cracking behavior.

  5. What Sequences on High-Field MR Best Depict Temporal Resolution of Experimental ICH and Edema Formation in Mice?

    Directory of Open Access Journals (Sweden)

    Mingchang Li

    2012-01-01

    Full Text Available Background and Purpose. Pilot study to examine the use of T1-, T2-, and T2*-weighted images for evaluating hematoma size and extent of edema in mouse brain at high field. Methods. Following collagenase-induced intracerebral hemorrhage, nine mice were imaged at 4.7 T using T1-, T2-, and T2*-weighted images for hematoma and edema quantitation on days 1, 3, 10, and 21 after surgery. Values were compared with morphometric analysis of cryosections at the time of final MR imaging. Results. For hematoma quantitation, the Spearman correlation coefficient ( between T1 signal change and histology was 0.70 (<0.04 compared with =0.61 (<0.09 for T2*. The extent of perihematomal edema formation on cryosections was well reflected on T2 with =0.73 (<0.03. Conclusions. Within the limits of our pilot study, MR imaging on 4.7 T appears to approximate the temporal changes in hematoma and edema sizes in murine ICH well, thus laying the groundwork for longitudinal studies on hematoma resorption and edema formation.

  6. Formation and preservation of pedogenic carbonates in South India, links with paleo-monsoon and pedological conditions: Clues from Sr isotopes, U-Th series and REEs

    Science.gov (United States)

    Violette, Aurélie; Riotte, Jean; Braun, Jean-Jacques; Oliva, Priscia; Marechal, Jean-Christophe; Sekhar, M.; Jeandel, Catherine; Subramanian, S.; Prunier, Jonathan; Barbiero, Laurent; Dupre, Bernard

    2010-12-01

    The influence of the pedogenic and climatic contexts on the formation and preservation of pedogenic carbonates in a climosequence in the Western Ghats (Karnataka Plateau, South West India) has been studied. Along the climosequence, the current mean annual rainfall (MAR) varies within a 80 km transect from 6000 mm at the edge of the Plateau to 500 mm inland. Pedogenic carbonates occur in the MAR range of 500-1200 mm. In the semi-arid zone (MAR: 500-900 mm), carbonates occur (i) as thick hardpan calcretes on pediment slopes and (ii) as nodular horizons in polygenic black soils (i.e. vertisols). In the sub-humid zone (MAR: 900-1500 mm), pedogenic carbonates are disseminated in the black soil matrices either as loose, irregular and friable nodules of millimetric size or as indurated botryoidal nodules of centimetric to pluricentimetric size. They also occur at the top layers of the saprolite either as disseminated pluricentimetric indurated nodules or carbonate-cemented lumps of centimetric to decimetric size. Chemical and isotopic ( 87Sr/ 86Sr) compositions of the carbonate fraction were determined after leaching with 0.25 N HCl. The corresponding residual fractions containing both primary minerals and authigenic clays were digested separately and analyzed. The trend defined by the 87Sr/ 86Sr signatures of both labile carbonate fractions and corresponding residual fractions indicates that a part of the labile carbonate fraction is genetically linked to the local soil composition. Considering the residual fraction of each sample as the most likely lithogenic source of Ca in carbonates, it is estimated that from 24% to 82% (55% on average) of Ca is derived from local bedrock weathering, leading to a consumption of an equivalent proportion of atmospheric CO 2. These values indicate that climatic conditions were humid enough to allow silicate weathering: MAR at the time of carbonate formation likely ranged from 400 to 700 mm, which is 2- to 3-fold less than the current

  7. A coastal three-dimensional water quality model of nitrogen in Jiaozhou Bay linking field experiments with modelling.

    Science.gov (United States)

    Lu, Dongliang; Li, Keqiang; Liang, Shengkang; Lin, Guohong; Wang, Xiulin

    2017-01-15

    With anthropogenic changes, the structure and quantity of nitrogen nutrients have changed in coastal ocean, which has dramatically influenced the water quality. Water quality modeling can contribute to the necessary scientific grounding of coastal management. In this paper, some of the dynamic functions and parameters of nitrogen were calibrated based on coastal field experiments covering the dynamic nitrogen processes in Jiaozhou Bay (JZB), including phytoplankton growth, respiration, and mortality; particulate nitrogen degradation; and dissolved organic nitrogen remineralization. The results of the field experiments and box model simulations showed good agreement (RSD=20%±2% and SI=0.77±0.04). A three-dimensional water quality model of nitrogen (3DWQMN) in JZB was improved and the dynamic parameters were updated according to field experiments. The 3DWQMN was validated based on observed data from 2012 to 2013, with good agreement (RSD=27±4%, SI=0.68±0.06, and K=0.48±0.04), which testifies to the model's credibility. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Multiple Andreev-reflection in superconducting weak-links in the interaction with external microwave-fields

    International Nuclear Information System (INIS)

    Zimmermann, U.; Keck, K.

    1996-01-01

    We present calculated current-voltage characteristics (CVCs) of NS- and SNS-contacts, where the carrier transport is characterised by single and multiple Andreev-reflection (AR) in the presence of an external microwave field. Based on the Tien-Gordon model of multiphoton-assisted electron tunneling we describe the microwave field by an ac-voltage potential. This additional potential is added in the time-dependent Bogoliubov-de Gennes equations (BdGE) which describe inhomogeneous superconductors and in this way NS-phase boundaries. These modified BdGE are solved by single particle wave-functions, which contain the multiphoton emission and absorption processes of the quasi-particles (QPs). With this ansatz we obtain an extension of the BTK-theory for NS-contacts and the OTBK-theory for SNS-contacts. We show, that the calculated CVCs for NS-contacts are in the case of a vanishing probability for AR identical with the characteristics obtained with the Tien-Gordon model. For SNS-contacts we show theoretically that features in the CVCs appear at voltages V=(2Δ)/(ne)+m/n (ℎω)/e (n,m integers). This equation was initially found experimentally by Hoffmann-Soerensen et al. We are now able to explain their results and show that investigations of the interaction of multiple AR with an external microwave field give clear evidence for the occurrence of multiple AR in the junction. (orig.)

  9. Characteristics of depositional environment and evolution of Upper Cretaceous Mishrif Formation, Halfaya Oil field, Iraq based on sedimentary microfacies analysis

    Science.gov (United States)

    Zhong, Yuan; Zhou, Lu; Tan, Xiucheng; Guo, Rui; Zhao, Limin; Li, Fei; Jin, Zhimin; Chen, Yantao

    2018-04-01

    As one of the most important carbonate targets in the Middle East, Upper Cretaceous Mishrif Formation has been highlighted for a long time. Although consensus has been reached on the overall sedimentary background, disputes still exist in understanding the sedimentary environment changes among sub-regions due to relatively limited research, rare outcrop, and incomplete drilled core, which hinders the analysis on sedimentary environment and thus the horizontal and vertical correlation. In this study, taking the Halfaya Oil Field as an example, the sedimentary microfacies analysis method was introduced to comprehensively characterize the cored interval of Mishrif Formation, including Single Layers MC1-1 to MA2. A total of 11 sedimentary microfacies are identified through system identification of sedimentary microfacies and environmental analysis, with reference to the standard microfacies classification in the rimmed carbonate platform. Then three kinds of environments are identified through microfacies assemblage analysis, namely restricted platform, open platform, and platform margin. Systematic analyses indicate that the deposits are mainly developed in the open platform and platform margin. Meanwhile, rock-electricity interpretation model is established according to the electricity response to cored intervals, and is then employed to interpret the uncored intervals, which finally helps build the sedimentary evolution pattern through horizontal and vertical correlation. It is proposed that the Single Layers MC1-1 to MB2-3 were deposited in the open platform featured by low water level, including sub-environments of low-energy shoal within platform and inter-shoal sea; Single Layers MB2-2 to MB1-2B were deposited in the open platform and platform margin, including sub-environments of high-energy shoal on the platform margin, low-energy shoal within platform, inter-shoal sea, and open sea; and Single Layers MB1-2A to MA2 were again deposited in the open platform

  10. Effect of variable frequency electromagnetic field on deposit formation in installations with geothermal water in Sijarinjska spa (Serbia

    Directory of Open Access Journals (Sweden)

    Stojiljković Dragan T.

    2011-01-01

    Full Text Available In this paper we have examined the effect of variable frequency electromagnetic field generated with a homemade device on deposit formation in installations with geothermal water from Sijarinjska Spa. The frequency alteration of the electromagnetic field in time was made by means of the sinusoidal and saw-tooth function. In laboratory conditions, with the flow of geothermal water at 0.015 l/s and temperature of 60 °C for 6 hours through a zig-zag glass pipe, a multiple decrease of total deposit has been achieved. By applying the saw-tooth and sinusoidal function, the decrease in contents of calcium and deposit has been achieved by 8 and 6 times, respectively. A device was also used on geothermal water installation in Sijarinjska Spa (Serbia, with the water flow through a 1'' diameter non-magnetic prochrome pipe at 0.15 l/s and temperature of 75 °C in a ten-day period. A significant decrease in total deposit and calcium in the deposit has also been achieved.

  11. Characterization and 3D reservoir modelling of fluvial sandstones of the Williams Fork Formation, Rulison Field, Piceance Basin, Colorado, USA

    International Nuclear Information System (INIS)

    Pranter, Matthew J; Vargas, Marielis F; Davis, Thomas L

    2008-01-01

    This study describes the stratigraphic characteristics and distribution of fluvial deposits of the Upper Cretaceous Williams Fork Formation in a portion of Rulison Field and addresses 3D geologic modelling of reservoir sand bodies and their associated connectivity. Fluvial deposits include isolated and stacked point-bar deposits, crevasse splays and overbank (floodplain) mudrock. Within the Williams Fork Formation, the distribution and connectivity of fluvial sandstones significantly impact reservoir productivity and ultimate recovery. The reservoir sandstones are primarily fluvial point-bar deposits interbedded with shales and coals. Because of the lenticular geometry and limited lateral extent of the reservoir sandstones (common apparent widths of ∼500–1000 ft; ∼150–300 m), relatively high well densities (e.g. 10 acre (660 ft; 200 m) spacing) are often required to deplete the reservoir. Heterogeneity of these fluvial deposits includes larger scale stratigraphic variability associated with vertical stacking patterns and structural heterogeneities associated with faults that exhibit lateral and reverse offsets. The discontinuous character of the fluvial sandstones and lack of distinct marker beds in the middle and upper parts of the Williams Fork Formation make correlation between wells tenuous, even at a 10 acre well spacing. Some intervals of thicker and amalgamated sandstones within the middle and upper Williams Fork Formation can be correlated across greater distances. To aid correlation and for 3D reservoir modelling, vertical lithology proportion curves were used to estimate stratigraphic trends and define the stratigraphic zonation within the reservoir interval. Object-based and indicator-based modelling methods have been applied to the same data and results from the models were compared. Results from the 3D modelling indicate that sandstone connectivity increases with net-to-gross ratio and, at lower net-to-gross ratios (<30%), differences exist in

  12. Toxicity of proton-metal mixtures in the field: Linking stream macroinvertebrate species diversity to chemical speciation and bioavailability

    Energy Technology Data Exchange (ETDEWEB)

    Stockdale, Anthony [Centre for Ecology and Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster LA1 4AP (United Kingdom); Tipping, Edward, E-mail: et@ceh.ac.uk [Centre for Ecology and Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster LA1 4AP (United Kingdom); Lofts, Stephen [Centre for Ecology and Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster LA1 4AP (United Kingdom); Ormerod, Stephen J. [Catchment Research Group, Cardiff School of Biosciences, Cardiff University, Cardiff CF10 3US (United Kingdom); Clements, William H. [Department of Fish, Wildlife, and Conservation Biology, Colorado State University, Fort Collins, CO 80523 (United States); Blust, Ronny [Ecophysiology, Biochemistry and Toxicology Group, Department of Biology, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium)

    2010-10-01

    Understanding metal and proton toxicity under field conditions requires consideration of the complex nature of chemicals in mixtures. Here, we demonstrate a novel method that relates streamwater concentrations of cationic metallic species and protons to a field ecological index of biodiversity. The model WHAM-F{sub TOX} postulates that cation binding sites of aquatic macroinvertebrates can be represented by the functional groups of natural organic matter (humic acid), as described by the Windermere Humic Aqueous Model (WHAM6), and supporting field evidence is presented. We define a toxicity function (F{sub TOX}) by summing the products: (amount of invertebrate-bound cation) x (cation-specific toxicity coefficient, {alpha}{sub i}). Species richness data for Ephemeroptera, Plecoptera and Trichoptera (EPT), are then described with a lower threshold of F{sub TOX}, below which all organisms are present and toxic effects are absent, and an upper threshold above which organisms are absent. Between the thresholds the number of species declines linearly with F{sub TOX}. We parameterised the model with chemistry and EPT data for low-order streamwaters affected by acid deposition and/or abandoned mines, representing a total of 412 sites across three continents. The fitting made use of quantile regression, to take into account reduced species richness caused by (unknown) factors other than cation toxicity. Parameters were derived for the four most common or abundant cations, with values of {alpha}{sub i} following the sequence (increasing toxicity) H{sup +} < Al < Zn < Cu. For waters affected mainly by H{sup +} and Al, F{sub TOX} shows a steady decline with increasing pH, crossing the lower threshold near to pH 7. Competition effects among cations mean that toxicity due to Cu and Zn is rare at lower pH values, and occurs mostly between pH 6 and 8.

  13. On the link between stress field and small-scale hydraulic fracture growth in anisotropic rock derived from microseismicity

    Science.gov (United States)

    Gischig, Valentin Samuel; Doetsch, Joseph; Maurer, Hansruedi; Krietsch, Hannes; Amann, Florian; Evans, Keith Frederick; Nejati, Morteza; Jalali, Mohammadreza; Valley, Benoît; Obermann, Anne Christine; Wiemer, Stefan; Giardini, Domenico

    2018-01-01

    To characterize the stress field at the Grimsel Test Site (GTS) underground rock laboratory, a series of hydrofracturing and overcoring tests were performed. Hydrofracturing was accompanied by seismic monitoring using a network of highly sensitive piezosensors and accelerometers that were able to record small seismic events associated with metre-sized fractures. Due to potential discrepancies between the hydrofracture orientation and stress field estimates from overcoring, it was essential to obtain high-precision hypocentre locations that reliably illuminate fracture growth. Absolute locations were improved using a transverse isotropic P-wave velocity model and by applying joint hypocentre determination that allowed for the computation of station corrections. We further exploited the high degree of waveform similarity of events by applying cluster analysis and relative relocation. Resulting clouds of absolute and relative located seismicity showed a consistent east-west strike and 70° dip for all hydrofractures. The fracture growth direction from microseismicity is consistent with the principal stress orientations from the overcoring stress tests, provided that an anisotropic elastic model for the rock mass is used in the data inversions. The σ1 stress is significantly larger than the other two principal stresses and has a reasonably well-defined orientation that is subparallel to the fracture plane; σ2 and σ3 are almost equal in magnitude and thus lie on a circle defined by the standard errors of the solutions. The poles of the microseismicity planes also lie on this circle towards the north. Analysis of P-wave polarizations suggested double-couple focal mechanisms with both thrust and normal faulting mechanisms present, whereas strike-slip and thrust mechanisms would be expected from the overcoring-derived stress solution. The reasons for these discrepancies can be explained by pressure leak-off, but possibly may also involve stress field rotation around the

  14. Electric field-assisted formation of organically modified hydroxyapatite (ormoHAP) spheres in carboxymethylated gelatin gels.

    Science.gov (United States)

    Heinemann, C; Heinemann, S; Kruppke, B; Worch, H; Thomas, J; Wiesmann, H P; Hanke, T

    2016-10-15

    A biomimetic strategy was developed in order to prepare organically modified hydroxyapatite (ormoHAP) with spherical shape. The technical approach is based on electric field-assisted migration of calcium ions and phosphate ions into a hydrogel composed of carboxymethylated gelatin. The electric field as well as the carboxymethylation using glucuronic acid (GlcA) significantly accelerates the mineralization process, which makes the process feasible for lab scale production of ormoHAP spheres and probably beyond. A further process was developed for gentle separation of the ormoHAP spheres from the gelatin gel without compromising the morphology of the mineral. The term ormoHAP was chosen since morphological analyses using electron microscopy (SEM, TEM) and element analysis (EDX, FT-IR, XRD) confirmed that carboxymethylated gelatin molecules use to act as organic templates for the formation of nanocrystalline HAP. The hydroxyapatite (HAP) crystals self-organize to form hollow spheres with diameters ranging from 100 to 500nm. The combination of the biocompatible chemical composition and the unique structure of the nanocomposites is considered to be a useful basis for future applications in functionalized degradable biomaterials. A novel bioinspired mineralization process was developed based on electric field-assisted migration of calcium and phosphate ions into biochemically carboxymethylated gelatin acting as organic template. Advantages over conventional hydroxyapatite include particle size distribution and homogeneity as well as achievable mechanical properties of relevant composites. Moreover, specifically developed calcium ion or phosphate ion release during degradation can be useful to adjust the fate of bone cells in order to manipulate remodeling processes. The hollow structure of the spheres can be useful for embedding drugs in the core, encapsulated by the highly mineralized outer shell. In this way, controlled drug release could be achieved, which enables

  15. Field assessment of the enzyme linked immunosorbent assay for foot-and-mouth disease virus diagnosis and typing

    International Nuclear Information System (INIS)

    Smitsaart, E.; Fondevila, N.; Compaired, D.; Maradei, E.; Fernandez, E.

    1998-01-01

    The objective of the present study was to evaluate the enzyme linked immunosorbent assay (ELISA) in comparison with the complement fixation test (CFT) for the diagnosis and typing of foot-and-mouth disease (FMD) virus (FMDV). Diagnostic material was epithelium from either suspected cases of FMD or from animals experimentally infected with FMDV. Epithelial suspensions and supernatant fluids from cell culture passage were assayed by CFT and ELISA. The superiority of the ELISA over the CFT was demonstrated: 1) the detection rate was 23% higher than that of CFT on original (epithelial) suspensions (OS) submissions of all sample (positive and negative) and 30% higher on supernatant fluids from cell culture passage, 2) the detection rate of ELISA on OS of confirmed positive samples was 28% higher than that of CFT, 3) no significant differences were observed in the detection and typing rates between the PANAFTOSA and FAO/IAEA ELISA kits (P<0.05) and 4) the sensitivity of the ELISA was 16 to 85 times higher than that of CFT when serial dilutions of sample homogenates were examined. (author)

  16. Effects of static magnetic field on magnetosome formation and expression of mamA, mms13, mms6 and magA in Magnetospirillum magneticum AMB-1.

    Science.gov (United States)

    Wang, Xiaoke; Liang, Likun

    2009-05-01

    Magnetotactic bacteria produce nanometer-size intracellular magnetic crystals. The superior crystalline and magnetic properties of magnetosomes have been attracting much interest in medical applications. To investigate effects of intense static magnetic field on magnetosome formation in Magnetospirillum magneticum AMB-1, cultures inoculated with either magnetic or non-magnetic pre-cultures were incubated under 0.2 T static magnetic field or geomagnetic field. The results showed that static magnetic field could impair the cellular growth and raise C(mag) values of the cultures, which means that the percentage of magnetosome-containing bacteria was increased. Static magnetic field exposure also caused an increased number of magnetic particles per cell, which could contribute to the increased cellular magnetism. The iron depletion in medium was slightly increased after static magnetic field exposure. The linearity of magnetosome chain was also affected by static magnetic field. Moreover, the applied intense magnetic field up-regulated mamA, mms13, magA expression when cultures were inoculated with magnetic cells, and mms13 expression in cultures inoculated with non-magnetic cells. The results implied that the interaction of the magnetic field created by magnetosomes in AMB-1 was affected by the imposed magnetic field. The applied static magnetic field could affect the formation of magnetic crystals and the arrangement of the neighboring magnetosome. Copyright 2009 Wiley-Liss, Inc.

  17. Formation of Plant Canopy Hierarchies and Consequences for Water Use: Insights From Field Experiments and Individual Based Modeling of Weed-Crop Interactions

    Science.gov (United States)

    Berger, A. G.; McDonald, A. J.; Riha, S. J.

    2008-12-01

    In an agricultural landscape, water use is tightly linked to the dynamics of canopy development. When weeds are present, the plant community may develop leaf area faster than crop monocultures and several hierarchies of plants may be formed. The position of each individual plant within these hierarchies depends on the spatial arrangement of the plants, the initial sizes, and the availability of resources as determined by management, soil properties, weather, and competition. Together, these factors establish a highly dynamic system with nonlinear responses to the availability of resources (e.g. soil water) that is reflected in high levels of site and regional variability in crop yield losses due to weed interference. We developed a spatially-explicit, individual based model of plant competition to evaluate dynamic outcomes of crop-weed interactions and implications for water use. The model simulates the growth of individual plants using the light interception algorithms of the forest model MAESTRA, and estimates photosynthesis through the Farquhar-vonCaemmerer method. Transpiration and photosynthesis are coupled through stomatal conductance. Maximum stomatal conductance is determined by the photosynthetic demand for CO2, but under water stress, actual transpiration per plant is used to estimate stomatal conductance and then the actual rate of photosynthesis. We also used a novel approach to estimate profile water uptake, scaling the root zone of influence (volume of soil exploited by each individual plant) to plant biomass. Additive field experiments with maize in monoculture and in combination with high-density stands of a common annual weed species (A. theophrasti M.) were established to test model performance. Despite exceptionally dry conditions in the field in some years, we found no evidence that the maize-weed mixtures had less total soil water or different rates of water extraction through the profile than the maize monocrop. Furthermore, time series

  18. Field-Theoretical Investigations of the Influence of Mutual Coupling Effects on the Capacity of MIMO Wireless Links

    Science.gov (United States)

    Ndoumbè Mbonjo Mbonjo, H.; Wu, G.; Hansen, V.

    2005-05-01

    We present a MIMO channel model which takes into account mutual coupling effects at the receiver and transmitter array in order to assess the influence of mutual coupling effects on the capacity of MIMO channels. We evaluate the mutual impedances using a general approach based on the electric field integral equation (EFIE) and its implementation by the method of moments (MOM). We compute the capacity of a 2x2-MIMO system in a one path scenario for square half wavelength patch antenna elements and half wavelength dipole antenna elements. The capacity of the MIMO system with and without coupling increases compared to the single antenna transmission for the patch antenna elements. On the contrary for half wavelength dipole antenna elements we have found that the MIMO system degenerates to a one-transmitting, one-receiving antenna system due to mutual coupling.

  19. Applying new thinking from the linked and emerging fields of digital identity and privacy to information governance in health informatics.

    Science.gov (United States)

    Harrison, John; Booth, Nick

    2003-01-01

    Recent work in the emerging field of network or digital identity suggests a new approach to the design of informatics systems, in which the individual becomes the guardian of their own personal data, and is assisted in controlling access to it by an infrastructure that is aware of roles, such as 'doctor', and relationships, such as 'doctor-patient'.For these purposes, an 'identity' is defined as the history of a relationship between two entities, and thus encompasses not only name and address but also data that would usually be regarded as part of an electronic patient or health record. This paper presents a description of how such a true person-centric architecture might work, and shows how it can be seen as an evolution of current plans in the NHS for a national patient data spine. One application, the electronic transmission of prescriptions, is described in detail. Other applications, both within and without the healthcare field, are described in outline. The implementation of such a person-centric system requires a modest degree of technical innovation, but significant change in organisational and business models. It is suggested that there is a need for one or more not-for-profit trusts, each with a remit to act as host for an individual's digital identity, and as the individual's true agent. Service providers - such as healthcare organisations - will pay the trust for provision of authentication, and for the storage and transmission of a patient's data; the trust in turn will pay implementation partners, such as smart card issuers and providers of communication channels, acting on behalf of the individual.

  20. Linking field and laboratory studies to investigate nitrate removal using permeable reactive barrier technology during managed recharge

    Science.gov (United States)

    Gorski, G.; Beganskas, S.; Weir, W. B.; Redford, K.; Saltikov, C.; Fisher, A. T.

    2017-12-01

    We present data from a series of field and laboratory studies investigating mechanisms for the enhanced removal of nitrate during infiltration as a part of managed recharge. These studies combine physical, geochemical, and microbiological data collected during controlled infiltration experiments at both a plot and a laboratory scale using permeable reactive barrier (PRB) technology. The presence of a PRB, made of wood chips or biochar, enhances nitrate removal by stimulating the growth and productivity of native soil microbes to process nitrate via denitrification. Earlier work has shown that unamended soil can remove up to 50% of nitrate during infiltration at rates population changes below the PRB where most of the cycling occurs. Coupled with isotopic analyses, these results suggest that a PRB expands the range of infiltration rates at which significant nitrate can be removed by microbial activity. Further, nitrate removal occurs at different depths below the biochar and redwood chips, suggesting different mechanisms of nitrate removal in the presence of different PRB materials. In laboratory studies we flowed artificial groundwater through intact sediment cores collected at the same field site where we also ran infiltration tests. These experiments show that the fluid flow rate and the presence of a PRB exhibit primary control on nitrate removal during infiltration, and that the relationship between flow rate and nitrate removal is fundamentally different in the presence of a PRB. These data from multiple scales and flow regimes are combined to offer a deeper understanding how the use of PRB technology during infiltration can help address a significant non-point source issue at the surface-subsurface interface.

  1. Applying new thinking from the linked and emerging fields of digital identity and privacy to information governance in health informatics

    Directory of Open Access Journals (Sweden)

    John Harrison

    2003-12-01

    Full Text Available Recent work in the emerging field of network or digital identity suggests a new approach to the design of informatics systems, in which the individual becomes the guardian of their own personal data, and is assisted in controlling access to it by an infrastructure that is aware of roles, such as 'doctor', and relationships, such as 'doctor_patient'. For these purposes, an 'identity' is defined as the history of a relationship between two entities, and thus encompasses not only name and address but also data that would usually be regarded as part of an electronic patient or health record. This paper presents a description of how such a true person-centric architecture might work, and shows how it can be seen as an evolution of current plans in the NHS for a national patient data spine. One application, the electronic transmission of prescriptions, is described in detail. Other applications, both within and without the healthcare field, are described in outline. The implementation of such a person-centric system requires a modest degree of technical innovation, but significant change in organisational and business models. It is suggested that there is a need for one or more not-for-profit trusts, each with a remit to act as host for an individual's digital identity, and as the individual's true agent. Service providers - such as healthcare organisations - will pay the trust for provision of authentication, and for the storage and transmission of a patient's data; the trust in turn will pay implementation partners, such as smart card issuers and providers of communication channels, acting on behalf of the individual.

  2. Fluorescence spectroscopy for field surveillance of THM formation precursors to increase sustainable drinking water treatment for the water industry

    Science.gov (United States)

    Stutter, Marc; Cooper, Pat; Wyness, Adam; Allan, Richard; Weir, Paul; Frogbrook, Zoe; Haffey, Mark

    2017-04-01

    Our understanding of the composition and diversity of dissolved organic matter (DOM) in natural waters is improving rapidly with techniques such as fluorescence spectroscopy. For the water industry issues of the reaction of DOM and different processes used to reduce microbial contamination in water for public supply are a pressing concern. A range of processes can be used but the common disinfection by free chlorine can react with DOM to produce a group of substances referred to as disinfection by-products (DBPs) that have been linked to health concerns. Hence, management at water treatment works aims to remove DOM prior to the disinfection reaction or change the treatment method. Both are costly financially and in terms of process chemical, such as coagulents that work variably with different DOM forms. Hence, enabling methods of catchment management, which have long been associated with tackling other forms of pollution (e.g. N, P) through source-pathway-receptor concepts, are options for the water industry where catchment raw water source management is a possible sustainable addition to conventional treatment. This presentation looks at the requirements and ongoing work to inform source water management options using bench-top fluorescence excitation-emission spectroscopy and hand-held sensors to detect DBP precursors, namely trihalomethanes (THMs), in complex multi-source environments. We start by introducing the forms of DOM discernible in the fluorescence excitation-emission matrix, how these have been ascribed to different compounds by previous studies and what wavelengths are available for in-situ detection. We then discuss methodology issues for sample storage and standard materials. Then we draw on results from a national set of Scottish catchments and a small catchment study to evaluate relationships between THM compounds from standard assay and GC-MS detection against spectral DOM surrogates, including catchment hydrochemical and spatial data covariates

  3. PVTX characteristics of oil inclusions from Asmari formation in Kuh-e-Mond heavy oil field in Iran

    Science.gov (United States)

    Shariatinia, Zeinab; Haghighi, Manouchehr; Shafiei, Ali; Feiznia, Sadat; Zendehboudi, Sohrab

    2015-04-01

    Incorporating PVT properties and compositional evolution of oil inclusions into reservoir engineering simulator protocols can enhance understanding of oil accumulation, reservoir charge history, and migration events. Microthermometry and volumetric analysis have proven to be useful tools in compositional reconstitution and PT studies of oil inclusions and were used to determine composition, thermodynamic conditions, physical properties, and gas-to-oil ratios of heavy oil samples from Asmari carbonate reservoir in Kuh-e-Mond heavy oil field in Iran. PVT properties were predicted using a PVT black-oil model, and an acceptable agreement was observed between the experiments and the simulations. Homogenization temperatures were determined using microthermometry techniques in dolomite and calcite cements of the Asmari Formation, as well. Based on the homogenization temperature data, the undersaturated hydrocarbon mixture prior to formation of the gas cap migrated with a higher gas-to-oil ratio from a source rock. According to the oil inclusion data, the onset of carbonate cementation occurred at temperatures above 45 °C and that cementation was progressive through burial diagenesis. PVT black-oil simulator results showed that the reservoir pressure and temperature were set at 100 bar and 54 °C during the initial stages of oil migration. Compositional modeling implies that primary and secondary cracking in source rocks were responsible for retention of heavy components and migration of miscible three-phase flow during hydrocarbon evolution. The PT evolution of the petroleum inclusions indicates changes in thermodynamic properties and mobility due to phenomena such as cracking, mixing, or/and transport at various stages of oil migration.

  4. Phase-field modeling of microstructural pattern formation during directional solidification of peritectic alloys without morphological instability

    International Nuclear Information System (INIS)

    Shing Lo, Tak; Karma, Alain; Plapp, Mathis

    2001-01-01

    During the directional solidification of peritectic alloys, two stable solid phases (parent and peritectic) grow competitively into a metastable liquid phase of larger impurity content than either solid phase. When the parent or both solid phases are morphologically unstable, i.e., for a small temperature gradient/growth rate ratio (G/v p ), one solid phase usually outgrows and covers the other phase, leading to a cellular-dendritic array structure closely analogous to the one formed during monophase solidification of a dilute binary alloy. In contrast, when G/v p is large enough for both phases to be morphologically stable, the formation of the microstructure becomes controlled by a subtle interplay between the nucleation and growth of the two solid phases. The structures that have been observed in this regime (in small samples where convection effects are suppressed) include alternate layers (bands) of the parent and peritectic phases perpendicular to the growth direction, which are formed by alternate nucleation and lateral spreading of one phase onto the other as proposed in a recent model [R. Trivedi, Metall. Mater. Trans. A 26, 1 (1995)], as well as partially filled bands (islands), where the peritectic phase does not fully cover the parent phase which grows continuously. We develop a phase-field model of peritectic solidification that incorporates nucleation processes in order to explore the formation of these structures. Simulations of this model shed light on the morphology transition from islands to bands, the dynamics of spreading of the peritectic phase on the parent phase following nucleation, which turns out to be characterized by a remarkably constant acceleration, and the types of growth morphology that one might expect to observe in large samples under purely diffusive growth conditions

  5. Formation of gas-phase peroxides in a rural atmosphere: An interpretation of the recent SOS/SERON field results

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J.H.; Tang, I.N. [Brookhaven National Lab., Upton, NY (United States); Weinstein-Lloyd, J.B. [State Univ. of New York, Old Westbury, NY (United States). Chemistry/Physics Dept.

    1993-09-01

    Hydrogen perioxide (H{sub 2}O{sub 2}) and certain organic peroxides such as hydroxymethyl-hydroperoxide (HMHP), are gas-phase oxidants present in the atmosphere at ppbv concentration levels. These oxidants play an important role in atmospheric chemistry. In addition, precipitation containing H{sub 2}O{sub 2} is toxic to trees, and it has also been suggested that organic peroxides formed presumably by ozone reactions with biogenic alkenes are responsible for leaf disorders. Recently, we have developed a nonenzymatic method or aqueous-phase H{sub 2}O{sub 2} measurement, using Fenton reagent and fluorescent hydroxy- benzoic acid. The new method, in conjunction with the well-known method of p-hydroxyphenylacetic acid and horseradish peroxidase for total peroxides, and together with an improved gas scrubber to mitigate sampling line problems, has been successfully deployed in recent SOS/SERON field measurements in rural Georgia. For the first time, continuously measured and speciated gas-phase peroxide data have become available, making it possible to examine some aspects of the ozone chemistry leading to the formation of these oxidants. It is observed that daily H{sub 2}O{sub 2} maximum frequently occurs at a different time than does HMHP, and that H{sub 2}O{sub 2} concentration, but not HMHP, tends to correlate with solar fluxes measured at the same location. These findings seem to indicate that the formation mechanisms for H{sub 2}O{sub 2} and organic peroxides are basically different. It is likely that H{sub 2}O{sub 2} is formed from radical-radical recombination, while HMHP is formed by ozone-alkene reactions. Since the gas-phase ozone-alkene reactions are usually too slow to account for the diurnal concentration variations observed for HMHP, heterogeneous processes involving ozone and alkenes are also a possibility.

  6. Laboratory Experiments and Modeling for Interpreting Field Studies of Secondary Organic Aerosol Formation Using an Oxidation Flow Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez, Jose-Luis [Univ. of Colorado, Boulder, CO (United States)

    2016-02-01

    This grant was originally funded for deployment of a suite of aerosol instrumentation by our group in collaboration with other research groups and DOE/ARM to the Ganges Valley in India (GVAX) to study aerosols sources and processing. Much of the first year of this grant was focused on preparations for GVAX. That campaign was cancelled due to political reasons and with the consultation with our program manager, the research of this grant was refocused to study the applications of oxidation flow reactors (OFRs) for investigating secondary organic aerosol (SOA) formation and organic aerosol (OA) processing in the field and laboratory through a series of laboratory and modeling studies. We developed a gas-phase photochemical model of an OFR which was used to 1) explore the sensitivities of key output variables (e.g., OH exposure, O3, HO2/OH) to controlling factors (e.g., water vapor, external reactivity, UV irradiation), 2) develop simplified OH exposure estimation equations, 3) investigate under what conditions non-OH chemistry may be important, and 4) help guide design of future experiments to avoid conditions with undesired chemistry for a wide range of conditions applicable to the ambient, laboratory, and source studies. Uncertainties in the model were quantified and modeled OH exposure was compared to tracer decay measurements of OH exposure in the lab and field. Laboratory studies using OFRs were conducted to explore aerosol yields and composition from anthropogenic and biogenic VOC as well as crude oil evaporates. Various aspects of the modeling and laboratory results and tools were applied to interpretation of ambient and source measurements using OFR. Additionally, novel measurement methods were used to study gas/particle partitioning. The research conducted was highly successful and details of the key results are summarized in this report through narrative text, figures, and a complete list of publications acknowledging this grant.

  7. Nonisotopic detection of human papillomavirus DNA in clinical specimens using a consensus PCR and a generic probe mix in an enzyme-linked immunosorbent assay format.

    Science.gov (United States)

    Kornegay, J R; Shepard, A P; Hankins, C; Franco, E; Lapointe, N; Richardson, H; Coutleé, F

    2001-10-01

    We assessed the value of a new digoxigenin (DIG)-labeled generic probe mix in a PCR-enzyme-linked immunosorbent assay format to screen for the presence of human papillomavirus (HPV) DNA amplified from clinical specimens. After screening with this new generic assay is performed, HPV DNA-positive samples can be directly genotyped using a reverse blotting method with product from the same PCR amplification. DNA from 287 genital specimens was amplified via PCR using biotin-labeled consensus primers directed to the L1 gene. HPV amplicons were captured on a streptavidin-coated microwell plate (MWP) and detected with a DIG-labeled HPV generic probe mix consisting of nested L1 fragments from types 11, 16, 18, and 51. Coamplification and detection of human DNA with biotinylated beta-globin primers served as a control for both sample adequacy and PCR amplification. All specimens were genotyped using a reverse line blot assay (13). Results for the generic assay using MWPs and a DIG-labeled HPV generic probe mix (DIG-MWP generic probe assay) were compared with results from a previous analysis using dot blots with a radiolabeled nested generic probe mix and type-specific probes for genotyping. The DIG-MWP generic probe assay resulted in high intralaboratory concordance in genotyping results (88% versus 73% agreement using traditional methods). There were 207 HPV-positive results using the DIG-MWP method and 196 positives using the radiolabeled generic probe technique, suggesting slightly improved sensitivity. Only one sample failed to test positive with the DIG-MWP generic probe assay in spite of a positive genotyping result. Concordance between the two laboratories was nearly 87%. Approximately 6% of samples that were positive or borderline when tested with the DIG-MWP generic probe assay were not detected with the HPV type-specific panel, perhaps representing very rare or novel HPV types. This new method is easier to perform than traditional generic probe techniques and uses

  8. Polycyclic Aromatic Hydrocarbon Emission in Spitzer /IRS Maps. II. A Direct Link between Band Profiles and the Radiation Field Strength

    Energy Technology Data Exchange (ETDEWEB)

    Stock, D. J.; Peeters, E., E-mail: dstock84@gmail.com [Department of Physics and Astronomy, University of Western Ontario, London, ON, N6A 3K7 (Canada)

    2017-03-10

    We decompose the observed 7.7 μ m polycyclic aromatic hydrocarbon (PAH) emission complexes in a large sample of over 7000 mid-infrared spectra of the interstellar medium using spectral cubes observed with the Spitzer /IRS-SL instrument. In order to fit the 7.7 μ m PAH emission complex we invoke four Gaussian components, which are found to be very stable in terms of their peak positions and widths across all of our spectra, and subsequently define a decomposition with fixed parameters, which gives an acceptable fit for all the spectra. We see a strong environmental dependence on the interrelationships between our band fluxes—in the H ii regions all four components are intercorrelated, while in the reflection nebulae (RNs) the inner and outer pairs of bands correlate in the same manner as previously seen for NGC 2023. We show that this effect arises because the maps of RNs are dominated by emission from strongly irradiated photodissociation regions, while the much larger maps of H ii regions are dominated by emission from regions much more distant from the exciting stars, leading to subtly different spectral behavior. Further investigation of this dichotomy reveals that the ratio of two of these components (centered at 7.6 and 7.8 μ m) is linearly related to the UV-field intensity (log G {sub 0}). We find that this relationship does not hold for sources consisting of circumstellar material, which are known to have variable 7.7 μ m spectral profiles.

  9. FORMATION EPOCHS, STAR FORMATION HISTORIES, AND SIZES OF MASSIVE EARLY-TYPE GALAXIES IN CLUSTER AND FIELD ENVIRONMENTS AT z = 1.2: INSIGHTS FROM THE REST-FRAME ULTRAVIOLET

    International Nuclear Information System (INIS)

    Rettura, Alessandro; Demarco, R.; Ford, H. C.; Rosati, P.; Gobat, R.; Nonino, M.; Fosbury, R. A. E.; Menci, N.; Strazzullo, V.; Mei, S.

    2010-01-01

    We derive stellar masses, ages, and star formation histories (SFHs) of massive early-type galaxies in the z = 1.237 RDCS1252.9-2927 cluster and compare them with those measured in a similarly mass-selected sample of field contemporaries drawn from the Great Observatories Origin Deep Survey South Field. Robust estimates of these parameters are obtained by comparing a large grid of composite stellar population models with 8-9 band photometry in the rest-frame near-ultraviolet, optical, and IR, thus sampling the entire relevant domain of emission of the different stellar populations. Additionally, we present new, deep U-band photometry of both fields, giving access to the critical far-ultraviolet rest frame, in order to empirically constrain the dependence of the most recent star formation processes on the environment. We also analyze the morphological properties of both samples to examine the dependence of their scaling relations on their mass and environment. We find that early-type galaxies, both in the cluster and in the field, show analogous optical morphologies, follow comparable mass versus size relation, have congruent average surface stellar mass densities, and lie on the same Kormendy relation. We also show that a fraction of early-type galaxies in the field employ longer timescales, τ, to assemble their mass than their cluster contemporaries. Hence, we conclude that while the formation epoch of early-type galaxies only depends on their mass, the environment does regulate the timescales of their SFHs. Our deep U-band imaging strongly supports this conclusion. We show that cluster galaxies are at least 0.5 mag fainter than their field contemporaries of similar mass and optical-to-infrared colors, implying that the last episode of star formation must have happened more recently in the field than in the cluster.

  10. CFD simulation of contrail formation in the near field of a commercial aircraft: Effect of fuel sulfur content

    Directory of Open Access Journals (Sweden)

    J.C. Khou

    2017-12-01

    Full Text Available Aircraft contrails may contribute to the global radiative forcing. In this context, the investigation of contrail formation in the near field of an aircraft may be helpful in developing strategies to reduce undesirable impacts. In this study, three-dimensional Reynolds-Averaged Navier-Stokes (RANS simulations of contrails produced by commercial aircraft during cruise flights were performed. A realistic geometry (herein a Boeing 737 was taken into account, including the engine core and bypass flows, which allows several parametrical studies and avoids using parameterizations to describe the plume's dilution. The objective was to simulate the early development of contrails in a fresh plume whose dilution was obtained with a spatial simulation of jet/vortex interaction. A coupling was carried out with a chemical and a microphysical model implemented in the numerical simulation code CEDRE to simulate particle growth using an Eulerian approach. The implemented microphysics model can simulate water condensation onto soot particles, taking into account their activation by adsorption of sulfur species. Our simulations show that sulfur dioxide is converted into sulfur trioxide and sulfuric acid at a rate of conversion close to 3 %, which is in good agreement with other studies. Ice-crystal growth was faster when the fuel sulfur content (FSC increased, allowing a visible contrail to appear earlier. These promising results confirm in situ observations and highlight the model's ability to simulate typical plume chemistry and complex microphysics/chemistry interactions coupled with detailed jet/vortex dynamics.

  11. A TIPS-TPDO-tetraCN-Based n-Type Organic Field-Effect Transistor with a Cross-linked PMMA Polymer Gate Dielectric.

    Science.gov (United States)

    Jung, Sungyeop; Albariqi, Mohammed; Gruntz, Guillaume; Al-Hathal, Thamer; Peinado, Alba; Garcia-Caurel, Enric; Nicolas, Yohann; Toupance, Thierry; Bonnassieux, Yvan; Horowitz, Gilles

    2016-06-15

    Recent improvement in the performance of the n-type organic semiconductors as well as thin gate dielectrics based on cross-linked polymers offers new opportunities to develop high-performance low-voltage n-type OFETs suitable for organic complementary circuits. Using TIPS-tetracyanotriphenodioxazine (TIPS-TPDO-tetraCN) and cross-linked poly(methyl methacrylate) (c-PMMA), respectively as n-type organic semiconductor and gate dielectric, linear regime field-effect mobility (1.8 ± 0.2) × 10(-2) cm(2) V(-1)s(-1), small spatial standard deviation of threshold voltage (∼0.1 V), and operating voltage less than 3 V are attainable with the same device structure and contact materials used commonly for p-type OFETs. Through comparative static and dynamic characterizations of c-PMMA and PMMA gate dielectrics, it is shown that both smaller thickness and larger relative permittivity of c-PMMA contributes to reduced operating voltage. Furthermore, negligible hysteresis brings evidence to small trap states in the semiconductor near gate dielectric of the n-type OFETs with c-PMMA. The use of TIPS-TPDO-tetraCN and c-PMMA is fully compatible with polyethylene terephthalate substrate, giving promise to various flexible applications.

  12. Pulsed electromagnetic fields partially preserve bone mass, microarchitecture, and strength by promoting bone formation in hindlimb-suspended rats.

    Science.gov (United States)

    Jing, Da; Cai, Jing; Wu, Yan; Shen, Guanghao; Li, Feijiang; Xu, Qiaoling; Xie, Kangning; Tang, Chi; Liu, Juan; Guo, Wei; Wu, Xiaoming; Jiang, Maogang; Luo, Erping

    2014-10-01

    A large body of evidence indicates that pulsed electromagnetic fields (PEMF), as a safe and noninvasive method, could promote in vivo and in vitro osteogenesis. Thus far, the effects and underlying mechanisms of PEMF on disuse osteopenia and/or osteoporosis remain poorly understood. Herein, the efficiency of PEMF on osteoporotic bone microarchitecture, bone strength, and bone metabolism, together with its associated signaling pathway mechanism, was systematically investigated in hindlimb-unloaded (HU) rats. Thirty young mature (3-month-old), male Sprague-Dawley rats were equally assigned to control, HU, and HU + PEMF groups. The HU + PEMF group was subjected to daily 2-hour PEMF exposure at 15 Hz, 2.4 mT. After 4 weeks, micro-computed tomography (µCT) results showed that PEMF ameliorated the deterioration of trabecular and cortical bone microarchitecture. Three-point bending test showed that PEMF mitigated HU-induced reduction in femoral mechanical properties, including maximum load, stiffness, and elastic modulus. Moreover, PEMF increased serum bone formation markers, including osteocalcin (OC) and N-terminal propeptide of type 1 procollagen (P1NP); nevertheless, PEMF exerted minor inhibitory effects on bone resorption markers, including C-terminal crosslinked telopeptides of type I collagen (CTX-I) and tartrate-resistant acid phosphatase 5b (TRAcP5b). Bone histomorphometric analysis demonstrated that PEMF increased mineral apposition rate, bone formation rate, and osteoblast numbers in cancellous bone, but PEMF caused no obvious changes on osteoclast numbers. Real-time PCR showed that PEMF promoted tibial gene expressions of Wnt1, LRP5, β-catenin, OPG, and OC, but did not alter RANKL, RANK, or Sost mRNA levels. Moreover, the inhibitory effects of PEMF on disuse-induced osteopenia were further confirmed in 8-month-old mature adult HU rats. Together, these results demonstrate that PEMF alleviated disuse-induced bone loss by promoting skeletal anabolic activities

  13. The formation of gold-rich seafloor sulfide deposits: Evidence from the Beebe hydrothermal vent field, Cayman Trough

    Science.gov (United States)

    Webber, Alexander P.; Roberts, Stephen; Murton, Bramley J.; Mills, Rachel A.; Hodgkinson, Matthew R. S.

    2017-06-01

    The Beebe vent field (BVF) in the Cayman Trough has built an auriferous massive sulfide deposit on the ultraslow spreading mid-Cayman spreading center. The genesis of auriferous sulfide deposits at mid-ocean ridges is not fully understood, although there is a growing recognition that slow and ultraslow spreading centers are conducive to gold mineralization. Analysis of hydrothermal precipitates from the BVF indicates that the highest gold contents are present within "beehive diffusers," which have developed a highly porous pyrrhotite framework. The beehive structure allows vent fluids to effuse slowly while allowing ingress of seawater to cool the fluid. The prevalence of pyrrhotite in the beehive samples, lack of sulfates, association between pyrrhotite and gold grains, and results of thermodynamic modeling suggest gold precipitation occurred under highly reduced conditions even during mixing with seawater. In contrast, high-temperature chimneys, with a single orifice, maintain high temperatures to the primary vent orifice and much of the gold is lost to seawater. Despite this, both chimney types are relatively gold-enriched, which points to a further underlying cause for high gold at the BVF such as interaction of hydrothermal fluids with ultramafic lithologies in the basement. The final gold composition of the deposit is partially controlled by loss of gold during mass-wasting of the material, with gold depletion most prevalent in blocks formed at beehive-type chimneys. The BVF demonstrates that the overall gold content of a massive sulfide deposit is the sum of basement, precipitation, and surface processes.Plain Language SummaryMineral deposits form on the seafloor at hydrothermal vent sites and are rich in metals including copper, zinc, lead, and sometimes precious metals like gold and silver. However, the processes controlling the amount of gold that ends up in these deposits is not clearly understood. In this article we show that as hydrothermal fluid vents

  14. An approach of understanding acid volcanics and tuffaceous volcaniclastics from field studies: A case from Tadpatri Formation, Proterozoic Cuddapah basin, Andhra Pradesh, India

    Science.gov (United States)

    Goswami, Sukanta; Upadhyay, P. K.; Bhagat, Sangeeta; Zakaulla, Syed; Bhatt, A. K.; Natarajan, V.; Dey, Sukanta

    2018-03-01

    The lower stratigraphic part of the Cuddapah basin is marked by mafic and felsic volcanism. Tadpatri Formation consists of a greater variety of rock types due to bimodal volcanism in the upper part. Presence of bimodal volcanism is an indication of continental rift setting. Various genetic processes involved in the formation of such volcanic sequence result in original textures which are classified into volcaniclastic and coherent categories. Detailed and systematic field works in Tadpatri-Tonduru transect of SW Cuddapah basin have provided information on the physical processes producing this diversity of rock types. Felsic volcanism is manifested here with features as finger print of past rhyolite-dacite eruptions. Acid volcanics, tuffs and associated shale of Tadpatri Formation are studied and mapped in the field. With supporting subordinate studies on geochemistry, mineralogy and petrogenesis of the volcanics to validate field features accurately, it is understood that volcanism was associated with rifting and shallow marine environmental condition. Four facies (i.e., surge, flow, fall and resedimented volcaniclastic) are demarcated to describe stratigraphic units and volcanic history of the mapped area. The present contribution focuses on the fundamental characterization and categorization of field-based features diagnostic of silica-rich volcanic activities in the Tadpatri Formation.

  15. Formation of the Eurasia Basin in the Arctic Ocean as inferred from geohistorical analysis of the anomalous magnetic field

    Science.gov (United States)

    Glebovsky, V. Yu.; Kaminsky, V. D.; Minakov, A. N.; Merkur'ev, S. A.; Childers, V. A.; Brozena, J. M.

    2006-07-01

    A new combined magnetic database and a magnetic-profile map are developed for the Eurasia Basin as a result of adjusting all available historical and recent Russian and American magnetic data sets. The geohistorical analysis of magnetic data includes several steps: identification of linear magnetic anomalies along each trackline, calculation of the Euler rotation pole positions for the relative motion of the North American and Eurasian plates, analysis of temporal and spatial variations in the spreading rate, and plate reconstructions. The pattern of key Cenozoic magnetic isochrons (24, 20, 18, 13, 6, 5, 2a) is constructed for the entire Eurasia Basin. In the western half of the basin, this pattern is consistent with a recently published scheme [16]. In its eastern half, magnetic isochrons are determined in detail for the first time and traced up to the Laptev Sea shelf. The main stages in the seafloor spreading are established for the Eurasia Basin. Each stage is characterized by a specific spreading rate and the degree of asymmetry of the basin opening. The revealed differences are traced along the Gakkel Ridge. Systematic patterns in wandering of the Eurasia Basin opening pole are established for particular stages. The continent-ocean transition zone corresponding to the primary rupture between plates is outlined in the region under consideration on the basis of gravimetric data. The nature of different potential fields and bottom topography on opposite sides of the Gakkel Ridge is discussed. The characteristic features of the basin-bottom formation at main stages of its evolution are specified on the basis of new and recently published data. The results obtained are in good agreement with plate geodynamics of the North Atlantic and the adjacent Arctic basins.

  16. The disruption of close binaries in the gravitational field of a supermassive black hole and the formation of hypervelocity stars

    Science.gov (United States)

    Dremova, G. N.; Dremov, V. V.; Tutukov, A. V.

    2014-05-01

    The formation of hypervelocity stars due to the dynamical capture of one component of a closebinary system by the gravitational field of a supermassive black hole (SMBH) is modeled. The mass of the black hole was varied between 106 and 109 M ⊙. In the model, the problem was considered first as a three-body problem (stage I) and then as an N-body problem (stage II). In the first stage, the effect of the inclination of the internal close-binary orbit (the motion of the components about the center of mass of the binary system) relative to the plane of the external orbit (the motion of the close binary around the SMBH) on the velocity with which one of the binary components is ejected was assessed. The initial binary orbits were generated randomly, with 10 000 orbits considered for each external orbit with a fixed pericenter distance r p . Analysis of the results obtained in the first stage of the modeling enables determination of the binary-orbit orientations that are the most favorable for high-velocity ejection, and estimation of the largest possible ejection velocities V max. The boundaries of the region of stellar disruption derived from the balance of tidal forces and self-gravitation are discussed using V max- r p plots, which generalize the results of the first stage of the modeling. Since a point-mass representation does not enable predictions about the survival of stars during close passages by a SMBH, there is the need for a second stage of the modeling, in which the tidal influence of the SMBH is considered. An approach treating a star like a structured finite object containing N bodies ( N = 4000) enables the derivation of more accurate limits for the zone of efficient acceleration of hypervelocity stars and the formulation of conditions for the tidal disruption of stars.

  17. Formation of space-charge bunches in a multivelocity-electron-beam-based microwave oscillator with a cathode unshielded from the magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Kalinin, Yu. A.; Starodubov, A. V.; Fokin, A. S., E-mail: alexander1989fokin@mail.ru [Saratov State University (Russian Federation)

    2017-02-15

    The influence of the magnitude and configuration of the magnetic field on the parameters of electron bunches formed in a multivelocity electron beam is analyzed. It is shown that the use of a cathode unshielded from the magnetic field and a nonuniform magnetic field increasing along the drift space enables the formation of compact electron bunches. The ratio between the current density in such bunches and the beam current density at the entrance to the drift space reaches 10{sup 6}, which results in a substantial broadening of the output microwave spectrum due to an increase in the amplitudes of the higher harmonics of the fundamental frequency.

  18. Do Small Format Supermarkets Improve the Shopping Experience?: Field Study Assessment of Two Alternative U.S. Strategies

    OpenAIRE

    Mark Lang; Primidya K. M. Soesilo; Richard Lancioni

    2012-01-01

    Industry reports have highlighted the trend for smaller format supermarkets in the food industry. Retailers such as Wal-Mart, Tesco, and Safeway see smaller format supermarkets as an opportunity to respond to the changing preferences of customers who are seeking a more convenient shoppability experience. This study investigates differences in small format retail strategies among retailers. A combination of direct observation in a naturalistic setting and Delphi methodologies were employed. A ...

  19. In-line formation of chemically cross-linked P84® co-polyimide hollow fibre membranes for H2/CO2 separation

    KAUST Repository

    Choi, Seung Hak

    2010-12-13

    In this study, chemically cross-linked asymmetric P84® co-polyimide hollow fibre membranes with enhanced separation performance were fabricated, using a dry-wet spinning process with an innovative in-line cross-linking step. The chemical modification was conducted by controlled immersion of the coagulated fibre in an aqueous 1,5-diamino-2-methylpentane (DAMP) cross-linker solution before the take-up. The effect of the cross-linker concentration on the thermal, mechanical, chemical and gas transport properties of the membranes was investigated. FT-IR/ATR analysis was used to identify the chemical changes in the polymer, while DSC analysis confirmed the changes in the Tg and the specific heat of the polymer upon cross-linking. Chemical cross-linking with a 10 wt.% aqueous DAMP solution strongly enhanced the H2/CO2 ideal selectivity from 5.3 to 16.1, while the H2 permeance of the membranes decreased from 7.06 × 10−3 to 1.01 × 10−3 m3(STP) m−2 h−1 bar−1 for a feed pressure of 1 bar at 25 °C. The increase of selectivity with decreasing permeance is somewhat higher than the slope in the Robeson upper bound, evidencing the positive effect of the cross-linking on the separation performance of the fibres. Simultaneously, the cross-linking leads to improved mechanical resistance of the membranes, which could be further enhanced by an additional thermal treatment. The produced membranes are therefore more suitable for use under harsh conditions and have a better overall performance than the uncross-linked ones.

  20. Scandinavian links

    DEFF Research Database (Denmark)

    Matthiessen, Christian Wichmann; Knowles, Richard D.

    2014-01-01

    centres, one joins more thinly populated regions, and the last one links peripheral areas. Two of them (The Great Belt Link and the Oresund Link) have been constructed and are in full operation. The third (the Fehmarnbelt Link) has been decided 2008 on bilateral government level. The three links...

  1. Probing star formation and feedback in dwarf galaxies. Integral field view of the blue compact galaxy Tololo 1937-423

    Science.gov (United States)

    Cairós, L. M.; González-Pérez, J. N.

    2017-12-01

    Context. Blue compact galaxies (BCG) are gas-rich, low-mass, small systems that form stars at unusually high rates. This makes them excellent laboratories for investigating the process of star-formation (SF) at galactic scales and the effects of massive stellar feedback on the interstellar (and intergalactic) medium. Aims: We analyzed the BCG Tololo 1937-423 using optical integral field spectroscopy to probe its morphology, stellar content, nebular excitation and ionization properties, and the kinematics of its warm ionized gas. Methods: Tololo 1937-423 was observed with the Visible Multi-Object Spectrograph at the Very Large Telescope. We took data in the wavelength range 4150-7400 Å, covering a field of view of 27″× 27″ on the sky with a spatial sampling of 0.̋67. From these data we built maps in the continuum and brighter emission lines, diagnostic line ratio maps, and velocity dispersion fields. We also generated the integrated spectrum of the main H II regions and young stellar clusters to determine reliable physical parameters and oxygen abundances. Results: We found that Tololo 1937-423 is currently undergoing an extended starburst. In the Hα maps we identified nine major clumps, aligned mostly northeast-southwest, and stretching to galactocentric distances ≥2 kpc. The galaxy presents a single continuum peak that is not cospatial with any knot in emission lines, indicating at least two relatively recent episodes of SF. The inhomogeneous dust distribution reachs its maximum (E(B-V) 0.97) roughly at the position of the continuum peak. We found shocked regions in the galaxy outer regions and at the edges of the SF knots. The oxygen abundance, 12 + log(O/H) 8.20 ± 0.1, is similar in all the SF regions, suggesting a chemically homogeneous ionized interstellar medium over spatial scales of several kpc. The ionized gas kinematics displays an overall regular rotation around a northwest-southeast axis, with a maximum velocity of 70 ± 7 km s-1. Conclusions

  2. Effects of pulsed electromagnetic field (PEMF) stimulation on bone tissue like formation are dependent on the maturation stages of the osteoblasts.

    Science.gov (United States)

    Diniz, Pericles; Shomura, Kenji; Soejima, Kazuhisa; Ito, Gakuji

    2002-07-01

    The effects of pulsed electromagnetic field (PEMF, 15 Hz pulse burst, 7 mT peak) stimulation on bone tissue-like formation on osteoblasts (MC3T3-E1 cell line) in different stages of maturation were assessed to determine whether the PEMF stimulatory effect on bone tissue-like formation was associated with the increase in the number of cells and/or with the enhancement of the cellular differentiation. The cellular proliferation (DNA content), differentiation (alkaline phosphatase activity), and bone tissue-like formation (area of mineralized matrix) were determined at different time points. PEMF treatment of osteoblasts in the active proliferation stage accelerated cellular proliferation, enhanced cellular differentiation, and increased bone tissue-like formation. PEMF treatment of osteoblasts in the differentiation stage enhanced cellular differentiation and increased bone tissue-like formation. PEMF treatment of osteoblasts in the mineralization stage decreased bone tissue-like formation. In conclusion, PEMF had a stimulatory effect on the osteoblasts in the early stages of culture, which increased bone tissue-like formation. This stimulatory effect was most likely associated with enhancement of the cellular differentiation, but not with the increase in the number of cells. Copyright 2002 Wiley-Liss, Inc.

  3. Ectomycorrhizal fungal diversity and saprotrophic fungal diversity are linked to different tree community attributes in a field-based tree experiment.

    Science.gov (United States)

    Nguyen, Nhu H; Williams, Laura J; Vincent, John B; Stefanski, Artur; Cavender-Bares, Jeannine; Messier, Christian; Paquette, Alain; Gravel, Dominique; Reich, Peter B; Kennedy, Peter G

    2016-08-01

    Exploring the link between above- and belowground biodiversity has been a major theme of recent ecological research, due in large part to the increasingly well-recognized role that soil microorganisms play in driving plant community processes. In this study, we utilized a field-based tree experiment in Minnesota, USA, to assess the effect of changes in plant species richness and phylogenetic diversity on the richness and composition of both ectomycorrhizal and saprotrophic fungal communities. We found that ectomycorrhizal fungal species richness was significantly positively influenced by increasing plant phylogenetic diversity, while saprotrophic fungal species richness was significantly affected by plant leaf nitrogen content, specific root length and standing biomass. The increasing ectomycorrhizal fungal richness associated with increasing plant phylogenetic diversity was driven by the combined presence of ectomycorrhizal fungal specialists in plots with both gymnosperm and angiosperm hosts. Although the species composition of both the ectomycorrhizal and saprotrophic fungal communities changed significantly in response to changes in plant species composition, the effect was much greater for ectomycorrhizal fungi. In addition, ectomycorrhizal but not saprotrophic fungal species composition was significantly influenced by both plant phylum (angiosperm, gymnosperm, both) and origin (Europe, America, both). The phylum effect was caused by differences in ectomycorrhizal fungal community composition, while the origin effect was attributable to differences in community heterogeneity. Taken together, this study emphasizes that plant-associated effects on soil fungal communities are largely guild-specific and provides a mechanistic basis for the positive link between plant phylogenetic diversity and ectomycorrhizal fungal richness. © 2016 John Wiley & Sons Ltd.

  4. Calculations on the development in space and time of the temperature field around a repository of medium and high active wastes in a salt formation

    International Nuclear Information System (INIS)

    Delisle, G.

    1980-01-01

    The concept of nuclear waste disposal of th of the Federal Republic of Germany calls for the burial of the wastes within a salt formation. A small portion of the wastes will generate heat after the disposal procedure. A temperature rise within the salt formation, in space and time limited, will be the consequence. The temperature change at any point in the near or far field of the disporal area can be calculated with the aid of numerical models. The thermal parameters representative for the bulk material of the Zechstein formation in NW-Germany, on which the calculations are based, will be discussed in detail. The interrelation between the concentration of heat producing wastes in the disposal field and the maximum average temperature in the salt formation will be treated. By defining numerical models, which are based on assumed shapes of a salt dome and a disposal area, the temperature development in the near and far field of a nuclear repository are shown. (orig.) [de

  5. Phase-field simulation of microstructure formation in technical castings - A self-consistent homoenthalpic approach to the micro-macro problem

    Science.gov (United States)

    Böttger, B.; Eiken, J.; Apel, M.

    2009-10-01

    Performing microstructure simulation of technical casting processes suffers from the strong interdependency between latent heat release due to local microstructure formation and heat diffusion on the macroscopic scale: local microstructure formation depends on the macroscopic heat fluxes and, in turn, the macroscopic temperature solution depends on the latent heat release, and therefore on the microstructure formation, in all parts of the casting. A self-consistent homoenthalpic approximation to this micro-macro problem is proposed, based on the assumption of a common enthalpy-temperature relation for the whole casting which is used for the description of latent heat production on the macroscale. This enthalpy-temperature relation is iteratively obtained by phase-field simulations on the microscale, thus taking into account the specific morphological impact on the latent heat production. This new approach is discussed and compared to other approximations for the coupling of the macroscopic heat flux to complex microstructure models. Simulations are performed for the binary alloy Al-3at%Cu, using a multiphase-field solidification model which is coupled to a thermodynamic database. Microstructure formation is simulated for several positions in a simple model plate casting, using a one-dimensional macroscopic temperature solver which can be directly coupled to the microscopic phase-field simulation tool.

  6. Phase-field simulation of microstructure formation in technical castings - A self-consistent homoenthalpic approach to the micro-macro problem

    International Nuclear Information System (INIS)

    Boettger, B.; Eiken, J.; Apel, M.

    2009-01-01

    Performing microstructure simulation of technical casting processes suffers from the strong interdependency between latent heat release due to local microstructure formation and heat diffusion on the macroscopic scale: local microstructure formation depends on the macroscopic heat fluxes and, in turn, the macroscopic temperature solution depends on the latent heat release, and therefore on the microstructure formation, in all parts of the casting. A self-consistent homoenthalpic approximation to this micro-macro problem is proposed, based on the assumption of a common enthalpy-temperature relation for the whole casting which is used for the description of latent heat production on the macroscale. This enthalpy-temperature relation is iteratively obtained by phase-field simulations on the microscale, thus taking into account the specific morphological impact on the latent heat production. This new approach is discussed and compared to other approximations for the coupling of the macroscopic heat flux to complex microstructure models. Simulations are performed for the binary alloy Al-3at%Cu, using a multiphase-field solidification model which is coupled to a thermodynamic database. Microstructure formation is simulated for several positions in a simple model plate casting, using a one-dimensional macroscopic temperature solver which can be directly coupled to the microscopic phase-field simulation tool.

  7. Insights into Focused Fluid Conduit Formation from Comparing Seismic Chimneys and Pipes with Field Observations of Fluid Flow Manifestations in the Colorado Plateau

    Science.gov (United States)

    Karstens, J.; Berndt, C.

    2014-12-01

    The understanding of focused fluid flow in sedimentary basins builds on field geological observations and the interpretation of reflection seismic data, where fluid conduits manifest as anomalous amplitude patterns known as seismic chimneys or pipes. Seismic data is the most effective method for the analysis of entire fluid flow systems by constraining subsurface geometries, fluid accumulations and permeability barriers, but seismic data cannot provide information about the internal architecture, interaction with the bedrock and flow processes due to its coarse resolution. Field geological investigations of fluid conduit outcrops are capable of filling observation gaps on a sub-seismic scale and help constrain formation dynamics as well as hydraulic properties of fluid conduits and the bedrock. Here, we show that it is possible to correlate specific amplitude patterns of seismic chimneys with field observation of focused fluid conduits from the Colorado Plateau. The migrating fluids (gas, water, fluidized sediment) and their formation dynamics, which can be associated with different types of conduits (fractures, fluidizations, injections), result in distinguishable seismic signatures. These constrains improve the qualitative interpretation of seismic chimneys by adding information about migration and formation characteristics. A further integration of field geological and seismic investigation of focused fluid flow structures may help to quantify their hydraulic properties and how these evolve with time, which has important implications for the hydrocarbon prospection and the subsurface storage of wastewater and CO2.

  8. Advanced Technologies for Monitoring CO2 Saturation and Pore Pressure in Geologic Formations: Linking the Chemical and Physical Effects to Elastic and Transport Properties

    Energy Technology Data Exchange (ETDEWEB)

    Mavko, G.; Vanorio, T.; Vialle, S.; Saxena, N.

    2014-03-31

    Ultrasonic P- and S-wave velocities were measured over a range of confining pressures while injecting CO2 and brine into the samples. Pore fluid pressure was also varied and monitored together with porosity during injection. Effective medium models were developed to understand the mechanisms and impact of observed changes and to provide the means for implementation of the interpretation methodologies in the field. Ultrasonic P- and S-wave velocities in carbonate rocks show as much as 20-50% decrease after injection of the reactive CO2-brine mixture; the changes were caused by permanent changes to the rock elastic frame associated with dissolution of mineral. Velocity decreases were observed under both dry and fluid-saturated conditions, and the amount of change was correlated with the initial pore fabrics. Scanning Electron Microscope images of carbonate rock microstructures were taken before and after injection of CO2-rich water. The images reveal enlargement of the pores, dissolution of micrite (micron-scale calcite crystals), and pitting of grain surfaces caused by the fluid- solid chemical reactivity. The magnitude of the changes correlates with the rock microtexture – tight, high surface area samples showed the largest changes in permeability and smallest changes in porosity and elastic stiffness compared to those in rocks with looser texture and larger intergranular pore space. Changes to the pore space also occurred from flow of fine particles with the injected fluid. Carbonates with grain-coating materials, such as residual oil, experienced very little permanent change during injection. In the tight micrite/spar cement component, dissolution is controlled by diffusion: the mass transfer of products and reactants is thus slow and the fluid is expected to be close to thermodynamical equilibrium with the calcite, leading to very little dissolution, or even precipitation. In the microporous rounded micrite and macropores, dissolution is controlled by

  9. Geochemical characteristics and genetic types of natural gas in the Changxing-Feixianguan Formations from the Yuanba Gas Field in the Sichuan Basin, China

    Directory of Open Access Journals (Sweden)

    Xiaoqi Wu

    2016-08-01

    Full Text Available The Yuanba Gas Field is a large gas field in the marine strata with the largest burial depth in China up to date. The studies performed on the mentioned gas field have achieved significant progress made possible by determining the characteristics of reef flat reservoirs in the marine strata and the main controlling factors of hydrocarbon accumulation. However, there is no consensus on the origin of natural gases stored in the reservoir in the Changxing-Feixianguan Formations in the Yuanba and its adjacent area. The study on geochemical characteristics indicates that natural gases in the reservoir in the Changxing-Feixianguan Formations in the Yuanba Gas Field are mainly composed of alkane gases which are dominated by methane with dryness coefficients generally higher than 0.995. The CO2 and H2S display an average content of 8.55% and 6.47%, respectively. The δ13C1 and δ13C2 values are from −31.2‰ to −27.9‰, and from −29.9‰ to −25.0‰, respectively, displaying the positive carbon isotopic series. The δ13CCO2 values are generally higher than −8‰, and the δD1 values are from −156‰ to −107‰. The identification of gas origin and gas–source correlation indicate that the natural gases reservoired in the Changxing-Feixianguan Formations in the Yuanba Gas Field have been altered by thermochemical sulfate reduction, and they are mainly composed of oil cracking gases derived from the secondary cracking of oil generated by the sapropelic-prone source rocks in the Permian Longtan Formation. The CO2 in the gas pools are mainly inorganic and were derived from the interaction between the acidic fluid and carbonate reservoirs.

  10. Formation of ball streamers at a subnanosecond breakdown of gases at a high pressure in a nonuniform electric field

    Science.gov (United States)

    Beloplotov, D. V.; Tarasenko, V. F.; Sorokin, D. A.; Lomaev, M. I.

    2017-11-01

    The formation of a diffuse discharge plasma at a subnanosecond breakdown of a "cone-plane" gap filled with air, nitrogen, methane, hydrogen, argon, neon, and helium at various pressures has been studied. Nanosecond negative and positive voltage pulses have been applied to the conical electrode. The experimental data on the dynamics of plasma glow at the stage of formation and propagation of a streamer have been obtained with intensified charge-coupled device and streak cameras. It has been found that the formation of ball streamers is observed in all gases and at both polarities. A supershort avalanche electron beam has been detected behind the flat foil electrode in a wide range of pressures in the case of a negatively charged conical electrode. A mechanism of the formation of streamers at breakdown of various gases at high overvoltages has been discussed.

  11. Collagen cross-linking by adipose-derived mesenchymal stromal cells and scar-derived mesenchymal cells: Are mesenchymal stromal cells involved in scar formation?

    NARCIS (Netherlands)

    Bogaerdt, van den A.J.; Veen, van der A.G.; Zuijlen, van P.P.; Reijnen, L.; Verkerk, M.; Bank, R.A.; Middelkoop, E.; Ulrich, M.

    2009-01-01

    In this work, different fibroblast-like (mesenchymal) cell populations that might be involved in wound healing were characterized and their involvement in scar formation was studied by determining collagen synthesis and processing. Depending on the physical and mechanical properties of the tissues,

  12. Collagen cross-linking by adipose-derived mesenchymal stromal cells and scar-derived mesenchymal cells : Are mesenchymal stromal cells involved in scar formation?

    NARCIS (Netherlands)

    van den Bogaerdt, Antoon J.; van der Veen, Vincent C.; van Zuijlen, Paul P. M.; Reijnen, Linda; Verkerk, Michelle; Bank, Ruud A.; Middelkoop, Esther; Ulrich, Magda M. W.

    2009-01-01

    In this work, different fibroblast-like (mesenchymal) cell populations that might be involved in wound healing were characterized and their involvement in scar formation was studied by determining collagen synthesis and processing. Depending on the physical and mechanical properties of the tissues,

  13. Solcoseryl, a tissue respiration stimulating agent, significantly enhances the effect of capacitively coupled electric field on the promotion of bone formation around dental implants.

    Science.gov (United States)

    Ochi, Morio; Wang, Pao-Li; Ohura, Kiyoshi; Takashima, Shigenori; Kagami, Hiroyuki; Hirose, Yukito; Kaku, Tohru; Sakaguchi, Kunihiko

    2003-06-01

    In the present study we examined the combined effect of application of a capacitively coupled electric field (CCEF) and the tissue respiration stimulating agent, Solcoseryl, on the promotion of bone formation around dental implants histologically and mechanically. After a dental implant was inserted into each femur of Japanese white rabbits, Solcoseryl (2 ml/kg) was administered intravenously in the ear vein and a CCEF was applied for 4 h per day for 14 days. The degree of bone formation on microscopic observation, bone contact ratio, bone surface area ratio, and the level of removal torque of the implant in the Solcoseryl- and CCEF-treated group were significantly higher than the respective value in the control group, which had not been treated with Solcoseryl nor CCEF. Thus, the combination of CCEF stimulation and Solcoseryl effectively promoted the formation of new bone. It is suggested that the clinical use of a combination of CCEF stimulation and Solcoseryl for dental implants promotes osseointegration.

  14. Minimization principles for the coupled problem of Darcy-Biot-type fluid transport in porous media linked to phase field modeling of fracture

    Science.gov (United States)

    Miehe, Christian; Mauthe, Steffen; Teichtmeister, Stephan

    2015-09-01

    This work develops new minimization and saddle point principles for the coupled problem of Darcy-Biot-type fluid transport in porous media at fracture. It shows that the quasi-static problem of elastically deforming, fluid-saturated porous media is related to a minimization principle for the evolution problem. This two-field principle determines the rate of deformation and the fluid mass flux vector. It provides a canonically compact model structure, where the stress equilibrium and the inverse Darcy's law appear as the Euler equations of a variational statement. A Legendre transformation of the dissipation potential relates the minimization principle to a characteristic three field saddle point principle, whose Euler equations determine the evolutions of deformation and fluid content as well as Darcy's law. A further geometric assumption results in modified variational principles for a simplified theory, where the fluid content is linked to the volumetric deformation. The existence of these variational principles underlines inherent symmetries of Darcy-Biot theories of porous media. This can be exploited in the numerical implementation by the construction of time- and space-discrete variational principles, which fully determine the update problems of typical time stepping schemes. Here, the proposed minimization principle for the coupled problem is advantageous with regard to a new unconstrained stable finite element design, while space discretizations of the saddle point principles are constrained by the LBB condition. The variational principles developed provide the most fundamental approach to the discretization of nonlinear fluid-structure interactions, showing symmetric systems in algebraic update procedures. They also provide an excellent starting point for extensions towards more complex problems. This is demonstrated by developing a minimization principle for a phase field description of fracture in fluid-saturated porous media. It is designed for an

  15. Pre-injection Comparison of Methods for Sampling Formation Water and Associated Gas from a Monitoring Well at a Carbon Dioxide Injection Site, Citronelle Oil Field, Alabama

    Science.gov (United States)

    Conaway, C.; Thordsen, J. J.; Manning, M. A.; Cook, P. J.; Abedini, A. A.; Trautz, R. C.; Thomas, B.; Kharaka, Y. K.

    2012-12-01

    The chemical composition of formation water and associated gases from the lower Cretaceous Paluxy Formation was determined using four different sampling methods at a well in the Citronelle Oil Field, Alabama, a site that will be used for a carbon dioxide injection experiment. Prior to each of the two sampling periods, the well was cleaned from the drilling fluids and KCl solutions by producing at least three pore volumes of formation water. Accurate measurements of the chemical composition of groundwater or formation water, including dissolved gasses, and gas samples is essential in understanding subsurface geochemical processes occurring as a result of geologic carbon dioxide injection, which is used for enhanced oil recovery (EOR) and has been proposed as a means of carbon sequestration. In this study, formation water and gas samples for geochemical analyses were obtained from well D-9-8 #2 at Citronelle using nitrogen lift, submersible pump, U-Tube, and a downhole (Kuster) sampler. Field chemical analyses included electrical conductivity, hydrogen sulfide, alkalinity, and pH, and laboratory analyses included major, minor and trace elements by mass spectrometry and ion chromatography, dissolved carbon, organic acid anions, free and dissolved gas species. The formation water obtained from this well is a Na-Ca-Cl brine with a salinity of 160,000 and 200,000 mg/L total dissolved solids (TDS). Differences were evident between sampling methodologies, particularly in pH, Fe and alkalinity measurements. The results of the comparison demonstrate the difficulty and importance of preserving volatile analytes in samples, with the downhole sampler and U-Tube system performing most favorably in this aspect.

  16. The role of the ambipolar field in the formation of the EDF and the criteria of the local approximation

    Science.gov (United States)

    Yuan, Chengxun; Rabadanov, K. M.; Bogdanov, E. A.; Kudryavtsev, A. A.; Zhou, Zhongxiang

    2017-11-01

    It is shown that in the situation when the ambipolar field exceeds the heating field the local approximation (LA) for determining the EDF is not applicable even if the energy relaxation length of the electron is relatively small. Therefore, accurate results can be obtained only solving the kinetic equation in energy and spatial variables.

  17. The evolution of and starburst-agn connection in luminous and ultraluminous infrared galaxies and their link to globular cluster formation

    Science.gov (United States)

    Fiorenza, Stephanie Lynn

    The evolutionary connection between nuclear starbursts and active galactic nuclei (AGN) in luminous infrared galaxies (LIRGs; 1011 diagrams. I show that for the U/LIRGs in my sample the properties that describe their nuclear starbursts and AGN (e.g. star formation rate (SFR), L[O III], optical D parameter, D4000, and EW(Hdelta)) are independent of one another, ensuring that no biases affect correlations between these properties and objects' locations on the BPT diagrams. I then derive evolutionary paths on the BPT diagram involving [N II]/Halpha that are based on how these properties vary between two U/LIRGs positioned at the end-points. The paths involve U/LIRGs that decrease in SFR and increase in AGN activity. Paths with U/LIRGs that evolve into high luminosity AGN likely do so due to recent, strong starbursts. Second, to study how the properties of the IR power sources in U/LIRGs vary, I use a combination of photometric data points that I carefully measure (using photometry from SDSS, 2MASS, WISE, and Spitzer) and that I retrieve from catalogues (IRAS, AKARI, and ISO) to perform UV to FIR SED-fitting with CIGALE (Code Investigating GALaxy Emission) for 34 U/LIRGs from the IRAS 2 Jy Redshift Survey with 0.01 125 Myr) agree with previous results, while those with younger starbursts show a large dispersion in Mstar. I conclude that this is supporting evidence that the star formation histories and timescales at which the IR power sources in U/LIRGs evolve are responsible for the scatter found for the SFR-Mstar relationship. U/LIRGs that form from merging gas-rich disk galaxies could also represent a stage of galaxy evolution involving heavy formation of globular clusters (GCs). It has been suggested that a large number of stellar clusters form during the merging of two gas-rich disk galaxies, leading to open and young massive clusters with the latter likely evolving into GCs. Furthering our understanding of GC formation can uncover the connection between GCs and

  18. Effect of Annealing in Magnetic Field on Ferromagnetic Nanoparticle Formation in Cu-Al-Mn Alloy with Induced Martensite Transformation.

    Science.gov (United States)

    Titenko, Anatoliy; Demchenko, Lesya

    2016-12-01

    The paper considers the influence of aging of high-temperature phase on subsequent martensitic transformation in Cu-Al-Mn alloy. The morphology of behavior of martensitic transformation as a result of alloy aging under annealing in a constant magnetic field with different sample orientation relatively to the field direction and without field was studied for direct control of the processes of martensite induction at cooling. Temperature dependences of electrical resistance, magnetic susceptibility, and magnetization, as well as field dependences of magnetization, and phase composition were found. The tendency to the oriented growth of precipitated ferromagnetic phase nanoparticles in a direction of applied field and to an increase of their volume fraction under thermal magnetic treatment of material that favors a reversibility of induced martensitic transformation is observed.

  19. WIPI2 links LC3 conjugation with PI3P, autophagosome formation, and pathogen clearance by recruiting Atg12-5-16L1.

    Science.gov (United States)

    Dooley, Hannah C; Razi, Minoo; Polson, Hannah E J; Girardin, Stephen E; Wilson, Michael I; Tooze, Sharon A

    2014-07-17

    Mammalian cell homeostasis during starvation depends on initiation of autophagy by endoplasmic reticulum-localized phosphatidylinositol 3-phosphate (PtdIns(3)P) synthesis. Formation of double-membrane autophagosomes that engulf cytosolic components requires the LC3-conjugating Atg12-5-16L1 complex. The molecular mechanisms of Atg12-5-16L1 recruitment and significance of PtdIns(3)P synthesis at autophagosome formation sites are unknown. By identifying interacting partners of WIPIs, WD-repeat PtdIns(3)P effector proteins, we found that Atg16L1 directly binds WIPI2b. Mutation experiments and ectopic localization of WIPI2b to plasma membrane show that WIPI2b is a PtdIns(3)P effector upstream of Atg16L1 and is required for LC3 conjugation and starvation-induced autophagy through recruitment of the Atg12-5-16L1 complex. Atg16L1 mutants, which do not bind WIPI2b but bind FIP200, cannot rescue starvation-induced autophagy in Atg16L1-deficient MEFs. WIPI2b is also required for autophagic clearance of pathogenic bacteria. WIPI2b binds the membrane surrounding Salmonella and recruits the Atg12-5-16L1 complex, initiating LC3 conjugation, autophagosomal membrane formation, and engulfment of Salmonella. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  20. Study of the role of the covalently linked cell wall protein (Ccw14p) and yeast glycoprotein (Ygp1p) within biofilm formation in a flor yeast strain.

    Science.gov (United States)

    Moreno-García, J; Coi, A L; Zara, G; García-Martínez, T; Mauricio, J C; Budroni, M

    2018-03-01

    Flor yeasts are Saccharomyces cerevisiae strains noted by their ability to create a type of biofilm in the air-liquid interface of some wines, known as 'flor' or 'velum', for which certain proteins play an essential role. Following a proteomic study of a flor yeast strain, we deleted the CCW14 (covalently linked cell wall protein) and YGP1 (yeast glycoprotein) genes-codifying for two cell surface glycoproteins-in a haploid flor yeast strain and we reported that both influence the weight of the biofilm as well as cell adherence (CCW14).

  1. Linking the X3D Pathway to Integral Field Spectrographs: YSNR 1E 0102.2-7219 in the SMC as a Case Study

    Science.gov (United States)

    Vogt, Frédéric P. A.; Seitenzahl, Ivo R.; Dopita, Michael A.; Ruiter, Ashley J.

    2017-05-01

    The concept of the x3d pathway was introduced by Vogt et al. as a new approach to sharing and publishing three-dimensional structures interactively in online scientific journals. The core characteristics of the x3d pathway are that: (1) it does not rely on specific software, but rather a file format (x3d), (2) it can be implemented using fully open-source tools, and (3) article readers can access the interactive models using most main stream web browsers without the need for any additional plugins. In this article, we further demonstrate the potential of the x3d pathway to visualize data sets from optical integral field spectrographs. We use recent observations of the oxygen-rich young supernova remnant 1E 0102.2-7219 in the Small Magellanic Cloud to implement additional x3dom tools & techniques and expand the range of interactions that can be offered to article readers. In particular, we present a set of javascript functions allowing the creation and interactive handling of clip planes, effectively allowing users to take measurements of distances and angles directly from the interactive model itself.

  2. Formation of H I Clouds in Shock-compressed Interstellar Medium: Physical Origin of Angular Correlation between Filamentary Structure and Magnetic Field

    Science.gov (United States)

    Inoue, Tsuyoshi; Inutsuka, Shu-ichiro

    2016-12-01

    Recent observations of the neutral Galactic interstellar medium showed that filamentary structures of H I clouds are aligned with the interstellar magnetic field. Many interesting applications are proposed based on the alignment, such as measurement of magnetic field strength through the Chandrasekhar-Fermi method and removal of foreground dust emissions for the detection of inflationary polarized emission in the cosmic microwave background radiation. However, the physical origin of the alignment remains to be explained. To understand the mechanism, we examine the formation of H I clouds triggered by shock compression of the diffuse warm neutral medium using three-dimensional magnetohydrodynamic simulations. We show that the shock-compressed medium of density n˜ 1 cm-3 evolves into H I clouds with n˜ 50 cm-3 via thermal instability consistent with previous studies. We apply a machine vision transformation developed by Clark et al. to the simulated column density structures to measure angle correlation between filamentary structures of H I clouds and magnetic field. We find that the orientation of H I filaments depends on the environmental turbulent velocity field, particularly on the strength of shear strain in the direction of the magnetic field, which is controlled by the angle between the shock propagation direction and upstream magnetic field. When the strain along the magnetic field is weak, filamentary components of H I clouds lie perpendicular to the magnetic field. However, the filaments have come to align with the magnetic field, if we enhance the turbulent strain along the magnetic field or if we set turbulence in the preshock medium.

  3. Formation mechanism of axial macrosegregation of primary phases induced by a static magnetic field during directional solidification

    Science.gov (United States)

    Li, Xi; Fautrelle, Yves; Ren, Zhongming; Moreau, Rene

    2017-04-01

    Understanding the macrosegregation formed by applying magnetic fields is of high commercial importance. This work investigates how static magnetic fields control the solute and primary phase distributions in four directionally solidified alloys (i.e., Al-Cu, Al-Si, Al-Ni and Zn-Cu alloys). Experimental results demonstrate that significant axial macrosegregation of the solute and primary phases (i.e., Al2Cu, Si, Al3Ni and Zn5Cu phases) occurs at the initial solidification stage of the samples. This finding is accompanied by two interface transitions in the mushy zone: quasi planar → sloping → quasi planar. The amplitude of the macrosegregation of the primary phases under the magnetic field is related to the magnetic field intensity, temperature gradient and growth speed. The corresponding numerical simulations present a unidirectional thermoelectric (TE) magnetic convection pattern in the mushy zone as a consequence of the interaction between the magnetic field and TE current. Furthermore, a model is proposed to explain the peculiar macrosegregation phenomenon by considering the effect of the forced TE magnetic convection on the solute distribution. The present study not only offers a new approach to control the solute distribution by applying a static magnetic field but also facilitates the understanding of crystal growth in the solute that is controlled by the static magnetic field during directional solidification.

  4. Formation and cleaning function of physically cross-linked dual strengthened water-soluble chitosan-based core-shell particles.

    Science.gov (United States)

    Dong, Yanrui; Xiao, Congming

    2017-09-01

    Facile and mild ionic cross-linking and freezing/thawing technologies were applied to prepare double strengthened core-shell particles by using water-soluble chitosan (WSC), sodium alginate (SA) and poly(vinyl alcohol) (PVA) as starting materials. The aqueous solution contained WSC and PVA was dropped in ethanol to form beads. The beads were converted into WSC/PVA hydrogel particles by being subjected to three freeze/thaw cycles. Subsequently, ionic cross-linked hydrogel layer was formed around each WSC/PVA particle to generate core-shell particulates. Fourier transform infrared spectra confirmed the combination among various components. Dynamic mechanical thermal analysis indicated that the storage modulus of the core-shell hydrogel was improved obviously. Thermogravimetric analysis exhibited the thermal stability of the particles was also enhanced by incorporation of PVA. It was found that the particles were able to adsorb carbon dioxide, lead ion and copper ion. The adsorption capacities of dry particles toward carbon dioxide, Pb(II) and Cu(II) could reach 199.62, 39.28 and 26.03mg/g, respectively. The rates of the particles for binding Pb(II) and Cu(II) at initial stage were 26.57 and 4.30%/min, respectively. These experimental results suggested that the particles were an efficient sorbent for removing hazardous substances such as carbon dioxide and heavy-metal ions. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. The Role of Diffusion-Controlled Growth in the Formation of Uniform Iron Oxide Nanoparticles with a Link to Magnetic Hyperthermia

    Czech Academy of Sciences Publication Activity Database

    Smolková, I. S.; Kazantseva, N.E.; Babayan, V.; Vilcakova, J.; Pizúrová, Naděžda; Sáha, P.

    2017-01-01

    Roč. 17, č. 5 (2017), s. 2323-2332 ISSN 1528-7483 Institutional support: RVO:68081723 Keywords : DIPOLAR INTERACTIONS * MONODISPERSE NANOCRYSTALS * HEAT-GENERATION * FIELD * PARTICLES * MODEL * THERMOTHERAPY * OPTIMIZATION * FEASIBILITY * ASSEMBLIES Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 4.055, year: 2016

  6. Metal contamination at recreational boatyards linked to the use of antifouling paints-investigation of soil and sediment with a field portable XRF.

    Science.gov (United States)

    Lagerström, Maria; Norling, Matz; Eklund, Britta

    2016-05-01

    The application of a field portable X-ray fluorescence spectrometer (FPXRF) to measure Cu, Zn, and Pb in soil and sediments at recreational boatyards by Lake Mälaren in Sweden was investigated. Confirmatory chemical analysis on freeze-dried samples shows that, ex situ, the FPXRF produces definitive level data for Cu and Zn and quantitative screening data for Pb, according to USEPA criteria for data quality. Good agreement was also found between the ex situ measurements and the in situ screening. At each of the two studied boatyards, >40 in situ soil measurements were carried out. Statistical differences in soil concentration based on land use were consequently found: the areas used for boat storage and maintenance were significantly higher in Cu and Zn than the areas used for car parking and transportation. The metal pollution in the boat storage areas is therefore shown to be directly linked to hull maintenance activities during which metal-containing antifouling paint particles are shed, end up on the ground, and consequently pollute the soil. In the boat storage areas, the Cu and Zn concentrations often exceeded the national guideline values for soil. In this study, they were also shown to increase with increasing age of the boatyard operation. Pb soil concentrations were only elevated at a few measurement points, reflecting the phasing out of Pb compounds from antifouling products over the past 2 decades. In the surface sediments, concentrations of Cu and Zn were 2-3 times higher compared to deeper levels. No decrease in metal concentration with time was found in the sediments, indicating that boat owners are not complying with the ban of biocide-containing paints in freshwater introduced over 20 years ago.

  7. The Gothic shale of the Pennsylvanian Paradox Formation Greater Aneth Field (Aneth Unit) Southeastern Utah U.S.A.: Seal for Hydrocarbons and Carbon Dioxide Storage.

    Energy Technology Data Exchange (ETDEWEB)

    Heath, Jason E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Dewers, Thomas [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Chidsey, Thomas C. [Utah Geoglogical Survey, Salt Lake City, UT (United States); Carney, Stephanie M. [Utah Geoglogical Survey, Salt Lake City, UT (United States); Bereskin, S. R. [Bereskin and Associates, Salt Lake City (United States)

    2017-05-01

    Greater Aneth oil field, Utah’s largest oil producer, was discovered in 1956 and has produced over 483 million barrels of oil. Located in the Paradox Basin of southeastern Utah, Greater Aneth is a stratigraphic trap producing from the Pennsylvanian (Desmoinesian) Paradox Formation. Because Greater Aneth is a mature, major oil field in the western U.S., and has a large carbonate reservoir, it was selected to demonstrate combined enhanced oil recovery and carbon dioxide storage. The Aneth Unit in the northwestern part of the field has produced over 160 million barrels of the estimated 386 million barrels of original oil in place—a 42% recovery rate. The large amount of remaining oil made the Aneth Unit ideal to enhance oil recovery by carbon dioxide flooding and demonstrate carbon dioxide storage capacity.

  8. Link Detection with Wikipedia

    Science.gov (United States)

    He, Jiyin

    This paper describes our participation in the INEX 2008 Link the Wiki track. We focused on the file-to-file task and submitted three runs, which were designed to compare the impact of different features on link generation. For outgoing links, we introduce the anchor likelihood ratio as an indicator for anchor detection, and explore two types of evidence for target identification, namely, the title field evidence and the topic article content evidence. We find that the anchor likelihood ratio is a useful indicator for anchor detection, and that in addition to the title field evidence, re-ranking with the topic article content evidence is effective for improving target identification. For incoming links, we use exact match and retrieval method with language modeling approach, and find that the exact match approach works best. On top of that, our experiment shows that the semantic relatedness between Wikipedia articles also has certain ability to indicate links.

  9. Field investigation and spectral characterization of Banded Iron Formation, Odisha, India: Implications to hydration processes on Mars

    Science.gov (United States)

    Singh, M.; Singhal, J.; Rajesh, V. J.

    2015-10-01

    Banded iron formations are major rock units having hematite layers intermittent with silica rich layers and formed mainly by the sedimentary processes during Late-Archaean to Mid-Proterozoic time period. They found their significance as a major iron-ore deposits and the first terrestrial rock bodies with existing life signatures on Earth. Here, we propose Odisha BIFs as a probable analogue site to the martian layered hematite deposit and its implications in inferring the sedimentary processes,hydration and astrobiological activities on Mars. Hyperspectral analysis identifies the optimum bands for the identification of similar type of deposits on Mars. Odisha BIFs have been found well comparable with the existing analogue sites of Lake Superior and Carajas Formation, Brazil.

  10. The star formation histories of local group dwarf galaxies. I. Hubble space telescope/wide field planetary camera 2 observations

    Energy Technology Data Exchange (ETDEWEB)

    Weisz, Daniel R. [Department of Astronomy, University of California at Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 (United States); Dolphin, Andrew E. [Raytheon Company, 1151 East Hermans Road, Tucson, AZ 85756 (United States); Skillman, Evan D. [Minnesota Institute for Astrophysics, University of Minnesota, 116 Church Street SE, Minneapolis, MN 55455 (United States); Holtzman, Jon [Department of Astronomy, New Mexico State University, Box 30001, 1320 Frenger Street, Las Cruces, NM 88003 (United States); Gilbert, Karoline M.; Dalcanton, Julianne J.; Williams, Benjamin F., E-mail: drw@ucsc.edu [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States)

    2014-07-10

    We present uniformly measured star formation histories (SFHs) of 40 Local Group (LG) dwarf galaxies based on color-magnitude diagram (CMD) analysis from archival Hubble Space Telescope imaging. We demonstrate that accurate SFHs can be recovered from CMDs that do not reach the oldest main sequence turn-off (MSTO), but emphasize that the oldest MSTO is critical for precisely constraining the earliest epochs of star formation. We find that: (1) the average lifetime SFHs of dwarf spheroidals (dSphs) can be approximated by an exponentially declining SFH with τ ∼ 5 Gyr; (2) lower luminosity dSphs are less likely to have extended SFHs than more luminous dSphs; (3) the average SFHs of dwarf irregulars (dIrrs), transition dwarfs, and dwarf ellipticals can be approximated by the combination of an exponentially declining SFH (τ ∼ 3-4 Gyr) for lookback ages >10-12 Gyr ago and a constant SFH thereafter; (4) the observed fraction of stellar mass formed prior to z = 2 ranges considerably (80% for galaxies with M < 10{sup 5} M{sub ☉} to 30% for galaxies with M > 10{sup 7} M{sub ☉}) and is largely explained by environment; (5) the distinction between 'ultra-faint' and 'classical' dSphs is arbitrary; (6) LG dIrrs formed a significantly higher fraction of stellar mass prior to z = 2 than the Sloan Digital Sky Survey galaxies from Leitner and the SFHs from the abundance matching models of Behroozi et al. This may indicate higher than expected star formation efficiencies at early times in low mass galaxies. Finally, we provide all the SFHs in tabulated electronic format for use by the community.

  11. The Star Formation Histories of Local Group Dwarf Galaxies. I. Hubble Space Telescope/Wide Field Planetary Camera 2 Observations

    Science.gov (United States)

    Weisz, Daniel R.; Dolphin, Andrew E.; Skillman, Evan D.; Holtzman, Jon; Gilbert, Karoline M.; Dalcanton, Julianne J.; Williams, Benjamin F.

    2014-07-01

    We present uniformly measured star formation histories (SFHs) of 40 Local Group (LG) dwarf galaxies based on color-magnitude diagram (CMD) analysis from archival Hubble Space Telescope imaging. We demonstrate that accurate SFHs can be recovered from CMDs that do not reach the oldest main sequence turn-off (MSTO), but emphasize that the oldest MSTO is critical for precisely constraining the earliest epochs of star formation. We find that: (1) the average lifetime SFHs of dwarf spheroidals (dSphs) can be approximated by an exponentially declining SFH with τ ~ 5 Gyr (2) lower luminosity dSphs are less likely to have extended SFHs than more luminous dSphs; (3) the average SFHs of dwarf irregulars (dIrrs), transition dwarfs, and dwarf ellipticals can be approximated by the combination of an exponentially declining SFH (τ ~ 3-4 Gyr) for lookback ages >10-12 Gyr ago and a constant SFH thereafter; (4) the observed fraction of stellar mass formed prior to z = 2 ranges considerably (80% for galaxies with M 107 M ⊙) and is largely explained by environment; (5) the distinction between "ultra-faint" and "classical" dSphs is arbitrary; (6) LG dIrrs formed a significantly higher fraction of stellar mass prior to z = 2 than the Sloan Digital Sky Survey galaxies from Leitner and the SFHs from the abundance matching models of Behroozi et al. This may indicate higher than expected star formation efficiencies at early times in low mass galaxies. Finally, we provide all the SFHs in tabulated electronic format for use by the community. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained from the Data Archive at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555.

  12. 3D slicing of radiogenic heat production in Bahariya Formation, Tut oil field, North-Western Desert, Egypt.

    Science.gov (United States)

    Al-Alfy, I M; Nabih, M A

    2013-03-01

    A 3D block of radiogenic heat production was constructed from the subsurface total gamma ray logs of Bahariya Formation, Western Desert, Egypt. The studied rocks possess a range of radiogenic heat production varying from 0.21 μWm(-3) to 2.2 μWm(-3). Sandstone rocks of Bahariya Formation have higher radiogenic heat production than the average for crustal sedimentary rocks. The high values of density log of Bahariya Formation indicate the presence of iron oxides which contribute the uranium radioactive ores that increase the radiogenic heat production of these rocks. The average radiogenic heat production produced from the study area is calculated as 6.3 kW. The histogram and cumulative frequency analyses illustrate that the range from 0.8 to 1.2 μWm(-3) is about 45.3% of radiogenic heat production values. The 3D slicing of the reservoir shows that the southeastern and northeastern parts of the study area have higher radiogenic heat production than other parts. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

  13. Effect of ECRH and resonant magnetic fields on formation of magnetic islands in the T-10 tokamak plasma

    Science.gov (United States)

    Shestakov, E. A.; Savrukhin, P. V.

    2017-10-01

    Experiments in the T-10 tokamak demonstrated possibility of controlling the plasma current during disruption instability using the electron cyclotron resonance heating (ECRH) and the controlled operation of the ohmic current-holding system. Quasistable plasma discharge with repeating sawtooth oscillations can be restored after energy quench using auxiliary ECRH power when PEC / POH > 2–5. The external magnetic field generation system consisted of eight saddle coils that were arranged symmetrically relative to the equatorial plane of the torus outside of the vacuum vessel of the T-10 tokamak to study the possible resonant magnetic field effects on the rotation frequency of magnetic islands. The saddle coils power supply system is based on four thyristor converters with a total power of 300 kW. The power supply control system is based on Siemens S7 controllers. As shown by preliminary experiments, the interaction efficiency of external magnetic fields with plasma depends on the plasma magnetic configuration. Optimal conditions for slowing the rotation of magnetic islands were determined. Additionally, the direction of the error magnetic field in the T-10 tokamak was determined, and the threshold value of the external magnetic field was determined.

  14. Impacts of diagenetic process on reservoir quality of the Middle Cretaceous Upper Sarvak Formation in one of oil fields in the Abadan Plain, SW Iran

    Directory of Open Access Journals (Sweden)

    Ali Assadi

    2016-03-01

    Full Text Available During the precipitation of Sarvak formation imprints of climate, tectonic and sea level fluctuation lead to some of the most prolific reservoirs in Zagros and Persian Gulf basins. The reservoir quality of upper Sarvak formation in Abadan plain oil fields are highly influenced by various diagenetic process. Based on core studies, petrographic analysis, well logs and properm data from two key well in a giant field, diagenetic sequence is reconstructed and the main processes effecting the reservoir quality are discussed. Three main diagenetic environments including 1- marine diagenesis (Micritization, Bioturbation, marine cementation 2- meteoric diagenesis (mineralogy stability, recrystallization, meteoric cementation, mixing zone dolomitization, Dedolomitization, fabric and none fabric selective dissolution and finally 3- burial diagenesis (physical and chemical compaction, burial dolomitization, fracturing, burial cementation, Silicification and pyritization and some none fabric dissolution have affected the upper Sarvak formation after deposition. Dissolution of matrix and grain, especially aragonite shells was a main porosity creating process, and took place primarily by meteoric diagenesis. Diagenetic studies indicate meteoric environment products highly modified reservoir quality. Calcite cementation and compaction are the chief factors controlling the reduction properm whilst dissolution and fracturing have enhanced reservoir quality of the studied interval. This study resulted that distribution and intensity of diagenetic process are dominantly controlled pore systems and reservoir quality.

  15. A Three-dimensional Magnetohydrodynamic Simulation of the Formation of Solar Chromospheric Jets with Twisted Magnetic Field Lines

    Energy Technology Data Exchange (ETDEWEB)

    Iijima, H. [Institute for Space-Earth Environmental Research, Nagoya University, Furocho, Chikusa-ku, Nagoya, Aichi 464-0814 Japan (Japan); Yokoyama, T., E-mail: h.iijima@isee.nagoya-u.ac.jp [Department of Earth and Planetary Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)

    2017-10-10

    This paper presents a three-dimensional simulation of chromospheric jets with twisted magnetic field lines. Detailed treatments of the photospheric radiative transfer and the equations of state allow us to model realistic thermal convection near the solar surface, which excites various MHD waves and produces chromospheric jets in the simulation. A tall chromospheric jet with a maximum height of 10–11 Mm and lifetime of 8–10 minutes is formed above a strong magnetic field concentration. The magnetic field lines are strongly entangled in the chromosphere, which helps the chromospheric jet to be driven by the Lorentz force. The jet exhibits oscillatory motion as a natural consequence of its generation mechanism. We also find that the produced chromospheric jet forms a cluster with a diameter of several Mm with finer strands. These results imply a close relationship between the simulated jet and solar spicules.

  16. Development of a geothermal resource in a fractured volcanic formation: Case study of the Sumikawa Geothermal Field, Japan

    Energy Technology Data Exchange (ETDEWEB)

    Garg, S.K.; Pritchett, J.W.; Stevens, J.L.; Luu, L. [Maxwell Federal Div., Inc., San Diego, CA (United States); Combs, J. [Geo-Hills Associates, Los Altos, CA (United States)

    1996-11-01

    The principal purpose of this case study of the Sumikawa Geothermal Field is to document and to evaluate the use of drilling logs, surface and downhole geophysical measurements, chemical analyses, and pressure transient data for the assessment of a high temperature volcanic geothermal field. The work accomplished during Year 1 of this ongoing program is described in the present report. A brief overview of the Sumikawa Geothermal Field is given. The drilling information and downhole pressure, temperature, and spinner surveys are used to determine feedzone locations, pressures and temperatures. Available injection and production data from both slim holes and large-diameter wells are analyzed to evaluate injectivity/productivity indices and to investigate the variation of discharge rate with borehole diameter. Finally, plans for future work are outlined.

  17. Nanosecond pulsed electric fields induce poly(ADP-ribose) formation and non-apoptotic cell death in HeLa S3 cells.

    Science.gov (United States)

    Morotomi-Yano, Keiko; Akiyama, Hidenori; Yano, Ken-ichi

    2013-08-30

    Nanosecond pulsed electric fields (nsPEFs) have recently gained attention as effective cancer therapy owing to their potency for cell death induction. Previous studies have shown that apoptosis is a predominant mode of nsPEF-induced cell death in several cell lines, such as Jurkat cells. In this study, we analyzed molecular mechanisms for cell death induced by nsPEFs. When nsPEFs were applied to Jurkat cells, apoptosis was readily induced. Next, we used HeLa S3 cells and analyzed apoptotic events. Contrary to our expectation, nsPEF-exposed HeLa S3 cells exhibited no molecular signs of apoptosis execution. Instead, nsPEFs induced the formation of poly(ADP-ribose) (PAR), a hallmark of necrosis. PAR formation occurred concurrently with a decrease in cell viability, supporting implications of nsPEF-induced PAR formation for cell death. Necrotic PAR formation is known to be catalyzed by poly(ADP-ribose) polymerase-1 (PARP-1), and PARP-1 in apoptotic cells is inactivated by caspase-mediated proteolysis. Consistently, we observed intact and cleaved forms of PARP-1 in nsPEF-exposed and UV-irradiated cells, respectively. Taken together, nsPEFs induce two distinct modes of cell death in a cell type-specific manner, and HeLa S3 cells show PAR-associated non-apoptotic cell death in response to nsPEFs. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. Computational fluid dynamics simulation of the combustion process, emission formation and the flow field in an in-direct injection diesel engine

    Directory of Open Access Journals (Sweden)

    Barzegar Ramin

    2013-01-01

    Full Text Available In the present paper, the combustion process and emission formation in the Lister 8.1 I.D.I Diesel engine have been investigated using a Computational Fluid Dynamics (CFD code. The utilized model includes detailed spray atomization, mixture formation and distribution model which enable modeling the combustion process in spray/wall and spray/swirl interactions along with flow configurations. The analysis considers both part load and full load states. The global properties are presented separately resolved for the swirl chamber (pre-chamber and the main chamber. The results of model verify the fact that the equal amount of the fuel is burned in the main and pre-chamber at full load state while at part load the majority of the fuel is burned in the main chamber. Also, it is shown that the adherence of fuel spray on the pre-chamber walls is due to formation of a stagnation zone which prevents quick spray evaporation and plays an important role in the increase of soot mass fractions at this zone at full load conditions. The simulation results, such as the mean in-cylinder pressure, heat release rate and exhaust emissions are compared with the experimental data and show good agreement. This work also demonstrates the usefulness of multidimensional modeling for complex chamber geometries, such as in I.D.I Diesel engines, to gain more insight into the flow field, combustion process and emission formation.

  19. Evaluation of source rocks in the 5th member of the Upper Triassic Xujiahe Formation in the Xinchang Gas Field, the Western Sichuan Depression, China

    Directory of Open Access Journals (Sweden)

    Xiaoqi Wu

    2017-12-01

    Full Text Available The 5th member of the Upper Triassic Xujiahe Formation (T3x5 is one of the important targets for terrigenous natural gas exploration in the Xinchang Gas Field in the Western Sichuan Depression, however, the quality of the T3x5 source rocks is poorly studied and the understanding of it is controversial. Studies have been conducted on the development and organic geochemical characteristics of the T3x5 mudstone in the Xinchang Gas Field, and the results indicate that, the T3x5 mudstone in the Xinchang Gas Field display an average thickness of 285.3 m, and the thickness of each submember increases from north to south. The average TOC content, hydrocarbon potential (S1+S2 and chloroform bitumen “A” content of T3x5 mudstone are 2.17%, 2.26 mg/g and 0.264‰, respectively, with the organic abundance mainly reaching the standard of medium source rocks. The kerogen type index (TI is lower than 0 with the mean δ13C value of −25.0‰, indicating mainly humic and sapropelic-humic types of organic matters. The average vitrinite reflectance (RO value is 1.17%, indicating the stage after the peak of oil generation. The gas generation intensity of T3x5 mudstone is generally in the range of (3–16 × 108 m3/km2, which suggests the resource basis for the generation of medium-small gas fields. The total amount of natural gas generated by T3x5 mudstone in the Xinchang Gas Field is relatively low, and the generated gas cannot completely displace the water in the formation, therefore, the fullness of gas in the reservoirs is generally low, which causes the simultaneous production of gas and water and the low gas production in the process of production test.

  20. Excitation wavelength dependence and magnetic field effect on aerosol particle formation from a gaseous mixture of carbon disulphide and glyoxal

    Czech Academy of Sciences Publication Activity Database

    Morita, H.; Kanaya, S.; Bastl, Zdeněk

    2006-01-01

    Roč. 104, č. 19 (2006), s. 3003-3009 ISSN 0026-8976 Grant - others: MEXT (JP) 15085203 Institutional research plan: CEZ:AV0Z40400503 Keywords : aerosol particles * gas-phase photochemical reaction * magnetic field effect * carbon disulphide * glyoxal Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.690, year: 2006

  1. Bisphenol A accelerates toxic amyloid formation of human islet amyloid polypeptide: a possible link between bisphenol A exposure and type 2 diabetes.

    Directory of Open Access Journals (Sweden)

    Hao Gong

    Full Text Available Bisphenol A (BPA is a chemical compound widely used in manufacturing plastic products. Recent epidemiological studies suggest BPA exposure is positively associated with the incidence of type 2 diabetes mellitus (T2DM, however the mechanisms underlying this link remain unclear. Human islet amyloid polypeptide (hIAPP is a hormone synthesized and secreted by the pancreatic β-cells. Misfolding of hIAPP into toxic oligomers and mature fibrils can disrupt cell membrane and lead to β-cell death, which is regarded as one of the causative factors of T2DM. To test whether there are any connections between BPA exposure and hIAPP misfolding, we investigated the effects of BPA on hIAPP aggregation using thioflavin-T based fluorescence, transmission electronic microscopy, circular dichroism, dynamic light scattering, size-exclusion chromatography, fluorescence-dye leakage assay in an artificial micelle system and the generation of reactive oxygen species in INS-1 cells. We demonstrated that BPA not only dose-dependently promotes the aggregation of hIAPP and enhances the membrane disruption effects of hIAPP, but also promotes the extent of hIAPP aggregation related oxidative stress. Taken together, our results suggest that BPA exposure increased T2DM risk may involve the exacerbated toxic aggregation of hIAPP.

  2. Spring thermocline formation in the coastal zone of the southeastern Baltic Sea based on field data in 2010–2013

    Science.gov (United States)

    Chubarenko, I. P.; Demchenko, N. Yu.; Esiukova, E. E.; Lobchuk, O. I.; Karmanov, K. V.; Pilipchuk, V. A.; Isachenko, I. A.; Kuleshov, A. F.; Chugaevich, V. Ya.; Stepanova, N. B.; Krechik, V. A.; Bagaev, A. V.

    2017-09-01

    The transition from winter vertical mixing to the formation of the spring thermocline in the southeastern Baltic Sea is studied based on data from the hydrophysical measurements program (11 expeditions) in the Russian part of Gdansk Bay in March-June 2010, 2011, and 2013. CTD measurements were taken along the standard 18-km transect across the isobaths with a 500-m step abeam the city of Baltiysk. A set of frequently measured data was collected in a 1-2 week interval from the end of March to the beginning of May, which made it possible to analyze the transformation of the vertical thermal structure of water from inverse winter type to the summer stratification with the transition of temperature over the temperature of the density maximum. Series of repeated measurements at the deep and coastal stations as well as surface and subsurface towed measurements were carried out. The fact that lenses of freshened warmer water appear at the surface almost simultaneously with intensification of cold intrusions in intermediate (10-40 m) layers makes it possible not only to confirm the advective nature of the formation of the spring thermocline in the Baltic Sea, but also to hypothesize about the intensification of intrabasin exchange when winter-time vertical mixing ceases: the potential energy excess supported by vertical mixing in the 60-m upper quasi-homogeneous layer (UQL) of the Baltic Proper, in which the horizontal estuarine salinity gradient is significant, is converted to kinetic energy of exchange currents as the mixing process terminates. Such water dynamics makes it possible to explain the intensification of intrusions in the Baltic in spring and the formation of the cold intermediate layer due to the fast propagation of late-winter UQL water from the Bornholm Basin to the Baltic Proper. The results agree well with earlier published studies of other authors.

  3. Predicting the Sources and Formation Mechanisms of Evolved Lunar Crust by Linking K/Ca Ratios of Lunar Granites to Analogous Terrestrial Igneous Rocks

    Science.gov (United States)

    Mills, R. D.; Simon, J. I.

    2012-01-01

    Although silicic rocks (i.e. granites and rhyolites) comprise a minor component of the sampled portion of the lunar crust, recent remote sensing studies [e.g., 1-4] indicate that several un-sampled regions of the Moon have significantly higher concentrations of silicic material (also high in [K], [U], and [Th]) than sampled regions. Within these areas are morphological features that are best explained by the existence of chemically evolved volcanic rocks. Observations of silicic domes [e.g., 1-5] suggest that sizable networks of silicic melt were present during crust formation. Isotopic data indicate that silicic melts were generated over a prolonged timespan from 4.3 to 3.9 Ga [e.g., 6-8]. The protracted age range and broad distribution of silicic rocks on the Moon indicate that their petrogenesis was an important mechanism for secondary crust formation. Understanding the origin and evolution of such silicic magmas is critical to determining the composition of the lunar crustal highlands and will help to distinguish between opposing ideas for the Moon's bulk composition and differentiation. The two main hypotheses for generating silicic melts on Earth are fractional crystallization or partial melting. On the Moon silicic melts are thought to have been generated during extreme fractional crystallization involving end-stage silicate liquid immiscibility (SLI) [e.g. 9, 10]. However, SLI cannot account for the production of significant volumes of silicic melt and its wide distribution, as reported by the remote global surveys [1, 2, 3]. In addition, experimental and natural products of SLI show that U and Th, which are abundant in the lunar granites and seen in the remote sensing data of the domes, are preferentially partitioned into the depolymerized ferrobasaltic magma and not the silicic portion [11, 12]. If SLI is not the mechanism that generated silicic magmas on the Moon then alternative processes such as fractional crystallization (only crystal

  4. Microwaves from Mobile Phones Inhibit 53BP1 Focus Formation in Human Stem Cells More Strongly Than in Differentiated Cells: Possible Mechanistic Link to Cancer Risk.

    Science.gov (United States)

    Markovà, Eva; Malmgren, Lars O G; Belyaev, Igor Y

    2010-03-01

    It is widely accepted that DNA double-strand breaks (DSBs) and their misrepair in stem cells are critical events in the multistage origination of various leukemias and tumors, including gliomas. We studied whether microwaves from mobile telephones of the Global System for Mobile Communication (GSM) and the Universal Global Telecommunications System (UMTS) induce DSBs or affect DSB repair in stem cells. We analyzed tumor suppressor TP53 binding protein 1 (53BP1) foci that are typically formed at the sites of DSB location (referred to as DNA repair foci) by laser confocal microscopy. Microwaves from mobile phones inhibited formation of 53BP1 foci in human primary fibroblasts and mesenchymal stem cells. These data parallel our previous findings for human lymphocytes. Importantly, the same GSM carrier frequency (915 MHz) and UMTS frequency band (1947.4 MHz) were effective for all cell types. Exposure at 905 MHz did not inhibit 53BP1 foci in differentiated cells, either fibroblasts or lymphocytes, whereas some effects were seen in stem cells at 905 MHz. Contrary to fibroblasts, stem cells did not adapt to chronic exposure during 2 weeks. The strongest microwave effects were always observed in stem cells. This result may suggest both significant misbalance in DSB repair and severe stress response. Our findings that stem cells are most sensitive to microwave exposure and react to more frequencies than do differentiated cells may be important for cancer risk assessment and indicate that stem cells are the most relevant cellular model for validating safe mobile communication signals.

  5. Combustion studies in a fluidised bed-The link between temperature, NO{sub x} and N{sub 2}O formation, char morphology and coal type

    Energy Technology Data Exchange (ETDEWEB)

    Valentim, B.; Lemos de Sousa, M.J. [Centro de Geologia da Universidade do Porto, Faculdade de Ciencias, Praca de Gomes Teixeira, 4099-002, Porto (Portugal); Abelha, P.; Boavida, D.; Gulyurtlu, I. [Departamento de Engenharia Energetica e Controlo Ambiental (DEECA), Instituto Nacional de Engenharia, Tecnologia e Inovacao (INETI), Estrada do Paco do Lumiar, 22, Edif. J, 1649-038, Lisboa (Portugal)

    2006-06-06

    Five commercially available high volatile bituminous coals from different origins were studied with the objective of characterizing their petrographic nature with respect to emissions of NO{sub x} and N{sub 2}O. The chars produced [at temperatures ranging from 700 to 1000 {sup o}C] from these coals were also petrographic ally analyzed to assess the contribution of char to NO{sub x} and N{sub 2}O formation during combustion. Vitrinite-rich coals produced higher porous chars (cenospheres and tenuinetworks) than those that are rich in inertinite. The former coals were, however, found to release lower concentrations of NO. Consistent with previous works, N{sub 2}O emissions were observed to decrease significantly with temperature, however, on the whole, the N{sub 2}O emissions from vitrinite-rich high volatile coals were less than those from inertinite-rich coals. Additionally, high porous chars were found to give rise to lower emissions of NO and N{sub 2}O. (author)

  6. Nanophase Iron Oxides as an Ultraviolet Sunscreen for Ancient Photosynthetic Microbes: A Possible Link Between Early Organisms, Banded-Iron Formations, and the Oxygenation of the Atmosphere

    Science.gov (United States)

    Bishop, Janice L.; Rothschild, Lynn J.; Rothschild, Lynn J.; Rogoff, Dana A.

    2006-01-01

    We propose that nanophase iron oxide-bearing materials provided important niches for ancient photosynthetic microbes on the early Earth that ultimately led to the oxygenation of the Earth s atmosphere and the formation of iron oxide deposits. Atmospheric oxygen and ozone attenuate UV radiation on the Earth today providing substantial protection for photosynthetic organisms. With ultraviolet radiation fluxes likely to have been even higher on the early Earth than today, accessing solar radiation was particularly risky for early organisms. Yet, we know that photosynthesis arose then and played a critical role in subsequent evolution. Of primary importance was protection at approx.250-290 nm, where peak nucleic acid (approx.260 nm) and protein (approx.280 nm) absorptions occur. Nanophase ferric oxide/oxyhydroxide minerals absorb, and thus block, the lethal UV radiation, while transmitting light through much of the visible and near-infrared regions of interest to photosynthesis (400 to 1100 nm). Further, they were available in early environments, and are synthesized by many organisms. Based on ferric oxide/oxyhydroxide spectral properties, likely geologic processes, and the results of experiments with the photosynthetic organisms, Euglena sp. and Chlumydomonus reinhardtii, we propose a scenario where photosynthesis, and ultimately the oxygenation of the atmosphere, depended on the protection of early microbes by nanophase ferric oxides/oxyhydroxides. The results of this study are also applicable to other potentially habitable iron-bearing planetary bodies because of the evolutionary pressure to utilize solar radiation when available as an energy source.

  7. Mitochondrial permeability transition pore induction is linked to formation of the complex of ATPase C-subunit, polyhydroxybutyrate and inorganic polyphosphate.

    Science.gov (United States)

    Elustondo, P A; Nichols, M; Negoda, A; Thirumaran, A; Zakharian, E; Robertson, G S; Pavlov, E V

    Mitochondrial permeability transition pore (mPTP) opening allows free movement of ions and small molecules leading to mitochondrial membrane depolarization and ATP depletion that triggers cell death. A multi-protein complex of the mitochondrial ATP synthase has an essential role in mPTP. However, the molecular identity of the central 'pore' part of mPTP complex is not known. A highly purified fraction of mammalian mitochondria containing C-subunit of ATPase (C-subunit), calcium, inorganic polyphosphate (polyP) and polyhydroxybutyrate (PHB) forms ion channels with properties that resemble the native mPTP. We demonstrate here that amount of this channel-forming complex dramatically increases in intact mitochondria during mPTP activation. This increase is inhibited by both Cyclosporine A, an inhibitor of mPTP and Ruthenium Red, an inhibitor of the Mitochondrial Calcium Uniporter. Similar increases in the amount of complex formation occurs in areas of mouse brain damaged by ischemia-reperfusion injury. These findings suggest that calcium-induced mPTP is associated with de novo assembly of a channel comprising C-subunit, polyP and PHB.

  8. Actualistic and Geochemical Modeling of Reservoir Rock, CO2 and Formation Fluid Interaction, Citronelle Oil Field, Alabama

    Energy Technology Data Exchange (ETDEWEB)

    Weislogel, Amy [West Virginia Univ., Morgantown, WV (United States)

    2014-01-31

    This report includes description of the Citronelle field study area and the work carried out in the project to characterize the geology and composition of reservoir rock material and to collect an analyze the geochemical composition of produced fluid waters from the Citronelle field. Reservoir rock samples collected from well bore core were made into thin-sections and assessed for textural properties, including pore types and porosity distribution. Compositional framework grain modal data were collected via point-counting, and grain and cement mineralogy was assessed using SEM-EDS. Geochemistry of fluid samples is described and modeled using PHREEQC. Composition of rock and produced fluids were used as inputs for TOUGHREACT reactive transport modeling, which determined the rock-fluid system was in disequilibrium.

  9. Effects on micronuclei formation of 60-Hz electromagnetic field exposure with ionizing radiation, hydrogen peroxide, or c-Myc overexpression.

    Science.gov (United States)

    Jin, Yeung Bae; Kang, Ga-Young; Lee, Jae Seon; Choi, Jong-Il; Lee, Ju-Woon; Hong, Seung-Cheol; Myung, Sung Ho; Lee, Yun-Sil

    2012-04-01

    Epidemiological studies have demonstrated a possible correlation between exposure to extremely low-frequency magnetic fields (ELF-MF) and cancer. However, this correlation has yet to be definitively confirmed by epidemiological studies. The principal objective of this study was to assess the effects of 60 Hz magnetic fields in a normal cell line system, and particularly in combination with various external factors, via micronucleus (MN) assays. Mouse embryonic fibroblast NIH3T3 cells and human lung fibroblast WI-38 cells were exposed for 4 h to a 60 Hz, 1 mT uniform magnetic field with or without ionizing radiation (IR, 2 Gy), H(2)O(2) (100 μM) and cellular myelocytomatosis oncogene (c-Myc) activation. The results obtained showed no significant differences between the cells exposed to ELF-MF alone and the unexposed cells. Moreover, no synergistic effects were observed when ELF-MF was combined with IR, H(2)O(2), and c-Myc activation. Our results demonstrate that ELF-MF did not enhance MN frequency by IR, H(2)O(2) and c-Myc activation.

  10. Hydrochemical-isotopic tendencies to define hydraulic mobility of formation water at the Samaria-Sitio Grande oil field, Mexico

    Science.gov (United States)

    Birkle, Peter; Angulo, Marisela; Lima, Santos

    2006-02-01

    The chemical (major elements) and isotopic ( 2H, 3H, 13C, 18O) composition of formation water is presented for the Sitio Grande oilfield, SE-Mexico, extracted from 28 production wells from the carbonate reservoir at a depth between 3585 and 4545 m.b.s.l. The linear δ 18O/δD-trend explains the formation of reservoir water as part of three subsequent stages: a) the evaporation of marine water at the surface, causing enrichment of both, δ 18O and δD-values, b) a reversal trend with decreasing δ 18O-and δD-ratios by the extreme evaporation of brines and, c) the subsequent mixing with isotopically depleted meteoric water. A SW-NE directed flow direction of deep groundwater systems is indicated by parallel-oriented isoline trends of stable isotope ratios and conservative elements, supported by the dominance of parallel directed microfractures and extensional faults, and by tracer test results. The arrival of artificial tritium, three years after tracer injection in the well SG-85, reflects a) the importance of long-term monitoring of tracer tests, and b) an estimated flow velocity of 2.2×10 -5 m/s. As the arrival of the tracer was detected exclusively in three production wells towards the SW of the injection site, lateral migration of groundwater occurs mainly along defined, channel-like conducts with a narrow dispersion angle of 39 °. Surface water, injected as part of an enhanced oil recovery program, was not detected in the production zone by chemical and isotopic methods. This fact is not a proof for lacking hydraulic conductivity, as the large reservoir size and the termination of the injection program in 1996 could have caused a complete dilution of the injected fluids. Restricted vertical flow movement between reservoir layers and insignificant temperature-dependent reaction processes is indicated by the heterogeneous distribution of δ 18O-and Cl-values throughout the groundwater column of most reservoir zones. Little influence of water-rock interaction

  11. Megacity impacts on regional ozone formation: observations and WRF-Chem modeling for the MIRAGE-Shanghai field campaign

    Directory of Open Access Journals (Sweden)

    X. Tie

    2013-06-01

    Full Text Available The MIRAGE-Shanghai experiment was designed to characterize the factors controlling regional air pollution near a Chinese megacity (Shanghai and was conducted during September 2009. This paper provides information on the measurements conducted for this study. In order to have some deep analysis of the measurements, a regional chemical/dynamical model (version 3 of Weather Research and Forecasting Chemical model – WRF-Chemv3 is applied for this study. The model results are intensively compared with the measurements to evaluate the model capability for calculating air pollutants in the Shanghai region, especially the chemical species related to ozone formation. The results show that the model is able to calculate the general distributions (the level and the variability of air pollutants in the Shanghai region, and the differences between the model calculation and the measurement are mostly smaller than 30%, except the calculations of HONO (nitrous acid at PD (Pudong and CO (carbon monoxide at DT (Dongtan. The main scientific focus is the study of ozone chemical formation not only in the urban area, but also on a regional scale of the surrounding area of Shanghai. The results show that during the experiment period, the ozone photochemical formation was strongly under the VOC (volatile organic compound-limited condition in the urban area of Shanghai. Moreover, the VOC-limited condition occurred not only in the city, but also in the larger regional area. There was a continuous enhancement of ozone concentrations in the downwind of the megacity of Shanghai, resulting in a significant enhancement of ozone concentrations in a very large regional area in the surrounding region of Shanghai. The sensitivity study of the model suggests that there is a threshold value for switching from VOC-limited condition to NOx (nitric oxide and nitrogen dioxide-limited condition. The threshold value is strongly dependent on the emission ratio of NOx / VOCs. When the

  12. The congenital cataract-linked A2V mutation impairs tetramer formation and promotes aggregation of βB2-crystallin.

    Directory of Open Access Journals (Sweden)

    Jia Xu

    Full Text Available β/γ-Crystallins, the major structural proteins in human lens, are highly conserved in their tertiary structures but distinct in the quaternary structures. The N- and C-terminal extensions have been proposed to play a crucial role in mediating the size of β-crystallin assembly. In this research, we investigated the molecular mechanism underlying the congenital hereditary cataract caused by the recently characterized A2V mutation in βB2-crystallin. Spectroscopic experiments indicated that the mutation did not affect the secondary and tertiary structures of βB2-crystallin. The mutation did not affect the formation of βB2/βA3-crystallin heteromer as well as the stability and folding of the heteromer, suggesting that the mutation might not interfere with the protein interacting network in the lens. However, the tetramerization of βB2-crystallin at high protein concentrations was retarded by the A2V mutation. The mutation slightly decreased the thermal stability and promoted the thermal aggregation of βB2-crystallin. Although it did not influence the stability of βB2-crystallin against denaturation induced by chemical denaturants and UV irradiation, the A2V mutant was more prone to be trapped in the off-pathway aggregation process during kinetic refolding. Our results suggested that the A2V mutation might lead to injury of lens optical properties by decreasing βB2-crystallin stability against heat treatment and by impairing βB2-crystallin assembly into high-order homo-oligomers.

  13. Electrospinning covalently cross-linking biocompatible hydrogelators

    Science.gov (United States)

    Schultz, Kelly M.; Campo-Deaño, Laura; Baldwin, Aaron D.; Kiick, Kristi L.; Clasen, Christian; Furst, Eric M.

    2012-01-01

    Many hydrogel materials of interest are homogeneous on the micrometer scale. Electrospinning, the formation of sub-micrometer to micrometer diameter fibers by a jet of fluid formed under an electric field, is one process being explored to create rich microstructures. However, electrospinning a hydrogel system as it reacts requires an understanding of the gelation kinetics and corresponding rheology near the liquid-solid transition. In this study, we correlate the structure of electrospun fibers of a covalently cross-linked hydrogelator with the corresponding gelation transition and kinetics. Polyethylene oxide (PEO) is used as a carrier polymer in a chemically cross-linking poly(ethylene glycol)-high molecular weight heparin (PEG-HMWH) hydrogel. Using measurements of gelation kinetics from multiple particle tracking microrheology (MPT), we correlate the material rheology with the the formation of stable fibers. An equilibrated, cross-linked hydrogel is then spun and the PEO is dissolved. In both cases, microstructural features of the electrospun fibers are retained, confirming the covalent nature of the network. The ability to spin fibers of a cross-linking hydrogel system ultimately enables the engineering of materials and microstructural length scales suitable for biological applications. PMID:23459473

  14. Characterization of low contrast shale-sand reservoir using Poisson impedance inversion: Case study of Gumai formation, Jambas field Jambi Sub-basin

    Science.gov (United States)

    Haris, A.; Nenggala, Y.; Suparno, S.; Raguwanti, R.; Riyanto, A.

    2017-07-01

    Low impedance contrast between the shale-sand layer, which can be found in the situation where shale layer wrapped in the sand reservoir, is a challenging case for explorationist in characterizing sand distribution from shale layer. In this paper, we present the implementation of Poisson impedance in mapping sand distribution in Gumai formation, Jambas Field, Jambi Sub-basin. Gumai formation has become a prospective zone, which contains sandstone with strong laterally change. The characteristic of facies at Gumai formation, which is laterally changing, has been properly mapped based on the Acoustic impedance (AI) and Shear impedance (SI). These two impedances, which is yielded by performing seismic simultaneous inversion, is then combined to generate Poisson impedance. The Poisson impedance is conceptually formulated as a contrast between AI and a scaled SI with the scale is estimated from the gradient of the relationship between AI and SI. Our experiment shows that the Poisson impedance map is able to separate the sand distribution from the shale layer. Therefore the sand facies has been clearly delineated from the contrast of Poisson impedance.

  15. Nanosecond pulsed electric fields induce poly(ADP-ribose) formation and non-apoptotic cell death in HeLa S3 cells

    Energy Technology Data Exchange (ETDEWEB)

    Morotomi-Yano, Keiko; Akiyama, Hidenori [Institute of Pulsed Power Science, Kumamoto University, Kumamoto 860-8555 (Japan); Yano, Ken-ichi, E-mail: yanoken@kumamoto-u.ac.jp [Priority Organization for Innovation and Excellence, Kumamoto University, Kumamoto 860-8555 (Japan)

    2013-08-30

    Highlights: •Nanosecond pulsed electric field (nsPEF) is a new and unique means for life sciences. •Apoptosis was induced by nsPEF exposure in Jurkat cells. •No signs of apoptosis were detected in HeLa S3 cells exposed to nsPEFs. •Formation of poly(ADP-ribose) was induced in nsPEF-exposed HeLa S3 cells. •Two distinct modes of cell death were activated by nsPEF in a cell-dependent manner. -- Abstract: Nanosecond pulsed electric fields (nsPEFs) have recently gained attention as effective cancer therapy owing to their potency for cell death induction. Previous studies have shown that apoptosis is a predominant mode of nsPEF-induced cell death in several cell lines, such as Jurkat cells. In this study, we analyzed molecular mechanisms for cell death induced by nsPEFs. When nsPEFs were applied to Jurkat cells, apoptosis was readily induced. Next, we used HeLa S3 cells and analyzed apoptotic events. Contrary to our expectation, nsPEF-exposed HeLa S3 cells exhibited no molecular signs of apoptosis execution. Instead, nsPEFs induced the formation of poly(ADP-ribose) (PAR), a hallmark of necrosis. PAR formation occurred concurrently with a decrease in cell viability, supporting implications of nsPEF-induced PAR formation for cell death. Necrotic PAR formation is known to be catalyzed by poly(ADP-ribose) polymerase-1 (PARP-1), and PARP-1 in apoptotic cells is inactivated by caspase-mediated proteolysis. Consistently, we observed intact and cleaved forms of PARP-1 in nsPEF-exposed and UV-irradiated cells, respectively. Taken together, nsPEFs induce two distinct modes of cell death in a cell type-specific manner, and HeLa S3 cells show PAR-associated non-apoptotic cell death in response to nsPEFs.

  16. Integrated petrophysical and sedimentological study of the Middle Miocene Nullipore Formation (Ras Fanar Field, Gulf of Suez, Egypt): An approach to volumetric analysis of reservoirs

    Science.gov (United States)

    Afife, Mohamed M.; Sallam, Emad S.; Faris, Mohamed

    2017-10-01

    This study aims to integrate sedimentological, log and core analyses data of the Middle Miocene Nullipore Formation at the Ras Fanar Field (west central Gulf of Suez, Egypt) to evaluate and reconstruct a robust petrophysical model for this reservoir. The Nullipore Formation attains a thickness ranging from 400 to 980 ft and represents a syn-rift succession of the Middle Miocene marine facies. It consists of coralline-algal-reefal limestone, dolomitic limestone and dolostone facies, with few clay and anhydrite intercalations. Petrographically, seven microfacies types (MF1 to MF7) have been recognized and assembled genetically into three related facies associations (FA1 to FA3). These associations accumulated in three depositional environments: 1) peritidal flat, 2) restricted lagoon, and 3) back-shoal environments situated on a shallow inner ramp (homoclinal) setting. The studied rocks have been influenced by different diagenetic processes (dolomitization, cementation, compaction, authigenesis and dissolution), which led to diminishing and/or enhancing the reservoir quality. Three superimposed 3rd-order depositional sequences are included in the Nullipore succession displaying both retrogradational and aggradational packages of facies. Given the hydrocarbon potential of the Nullipore Formation, conventional well logs of six boreholes and core analyses data from one of these wells (RF-B12) are used to identify electrofacies zones of the Nullipore Formation. The Nullipore Formation has been subdivided into three electrofacies zones (the Nullipore-I, Nullipore-II, and Nullipore-III) that are well-correlated with the three depositional sequences. Results of petrographical studies and log analyses data have been employed in volumetric calculations to estimate the amount of hydrocarbon-in-place and then the ultimate recovery of the Nullipore reservoir. The volumetric calculations indicate that the total volume of oil-in-place is 371 MMSTB at 50% probability (P50), whereas

  17. Biostratigraphy, facies and sequence stratigraphy of the Sarvak Formation in the Ahwaz Oil Field, North Dezful Embayment Zone

    Directory of Open Access Journals (Sweden)

    Mohammad Hasan Kazemzadeh

    2016-08-01

    Full Text Available Paleontological studies lead to recognition of 21 genera and 16 species of benthic foraminifera, 5 genera and 6 species of planktonic foraminifera and 3 genera and 3 species of oligosteginids. The vertical distribution of fauna lead to identification of 5 biozones including: Favusella washitensis Range Zone, Oligostegina Assemblage Zone, Rudist debris Zone, Nezzazata-Alveolinids Assemblage Zone, Nezzazatinella-Dicyclina Assemblage Zone. Based on the indicated biozones, the age of the Sarvak Formation is Late Albian to Early Turonian in the study area. Eleven carbonate facies belonging to four environments including tidal flat, restricted and semi-restricted lagoon, shoal and open marine are recognized. The identified facies are deposited on the homoclinal ramp setting. Based on the vertical changes of facies and recognized depositional environments, four third-order depositional sequences are represented. The transgressive systems tracts mainly comprises of open marine facies including sponge spicule, oligosteginid, echinoid and benthic foraminifera, while the highstand systems tracts mainly consists of shoal facies rich in bioclast, and restricted and semi-restricted lagoon facies rich in porcellaneous and hyaline benthic foraminifera and peloid. The maximum flooding surface represented by open marine facies including echinoid and planktonic foraminifera

  18. Experimental Evidence of the Effect of a High Magnetic Field on the Stray Grains Formation in Cross-Section Change Region for Ni-Based Superalloy During Directional Solidification

    Science.gov (United States)

    Xuan, Weidong; Ren, Zhongming; Li, Chuanjun

    2015-04-01

    The effect of a high magnetic field on the stray grains in cross-section change region was investigated experimentally during directional solidification of superalloy. The microstructures showed that the high magnetic field significantly suppressed the stray grains formation in cross-section change region. Meanwhile, the temperature curves indicated that the nucleation undercooling was significantly increased in a high magnetic field. The effect of a high magnetic field on the stray grains was discussed based on the nucleation mechanism.

  19. FORMATION OF FUNDAMENTAL KNOWLEDGE OF STUDENTS IN THE FIELD OF METHODS OF MATHEMATICAL PHYSICS INTRAINING INVERSE PROBLEMS FOR DIFFERENTIAL EQUATIONS

    Directory of Open Access Journals (Sweden)

    В С Корнилов

    2016-12-01

    Full Text Available In article the attention that when training in the inverse problems for the differential equations at bachelors and undergraduates fundamental knowledge in the field of methods of mathematical physics whom allows to investigate various educational mathematical tasks successfully is formed is paid. Statements of educational inverse problems for the differential equations to which research methods of mathematical physics, and also the short scheme of their research with the formulation of the received results are applied are given. Such methods of mathematical physics as a method of characteristics, Fourier’s method, a convolution method, Kirchhoff’s formula which bachelors and undergraduates apply at the solution of the inverse problems on studies are shown.

  20. Multi-level slug tests in highly permeable formations: 2. Hydraulic conductivity identification, method verification, and field applications

    Science.gov (United States)

    Zlotnik, V.A.; McGuire, V.L.

    1998-01-01

    Using the developed theory and modified Springer-Gelhar (SG) model, an identification method is proposed for estimating hydraulic conductivity from multi-level slug tests. The computerized algorithm calculates hydraulic conductivity from both monotonic and oscillatory well responses obtained using a double-packer system. Field verification of the method was performed at a specially designed fully penetrating well of 0.1-m diameter with a 10-m screen in a sand and gravel alluvial aquifer (MSEA site, Shelton, Nebraska). During well installation, disturbed core samples were collected every 0.6 m using a split-spoon sampler. Vertical profiles of hydraulic conductivity were produced on the basis of grain-size analysis of the disturbed core samples. These results closely correlate with the vertical profile of horizontal hydraulic conductivity obtained by interpreting multi-level slug test responses using the modified SG model. The identification method was applied to interpret the response from 474 slug tests in 156 locations at the MSEA site. More than 60% of responses were oscillatory. The method produced a good match to experimental data for both oscillatory and monotonic responses using an automated curve matching procedure. The proposed method allowed us to drastically increase the efficiency of each well used for aquifer characterization and to process massive arrays of field data. Recommendations generalizing this experience to massive application of the proposed method are developed.Using the developed theory and modified Springer-Gelhar (SG) model, an identification method is proposed for estimating hydraulic conductivity from multi-level slug tests. The computerized algorithm calculates hydraulic conductivity from both monotonic and oscillatory well responses obtained using a double-packer system. Field verification of the method was performed at a specially designed fully penetrating well of 0.1-m diameter with a 10-m screen in a sand and gravel alluvial

  1. The weak interactions from 1950 to 1960: a quantitative bibliometric study of the formation of a field

    International Nuclear Information System (INIS)

    White, D.H.; Sullivan, D.

    1989-01-01

    A collaborative group of scientists and sociologists report on a bibliometric study of the literature on weak interactions between 1950 and 1960. The dominant problems of the period are discussed and the history of key events such as the discovery of parity violation in 1956 is examined. They also track the development of this area as a separate field of study in particle physics following the study of beta and muon decay, and the discovery of pions, kaons and hyper ions from cosmic rays. The study notes the surprising result that large numbers of scientists focused on a surprisingly small number of topics, such as kaon decay, the tau-theta puzzle and mixed states of the neutral kaon in 1956. In 1957, the topic was parity non-conservation. In 1959 it was V-A theory, the general theory of weak interactions. These discoveries obviously depended on advances in particle accelerators which occurred in this decade. (UK)

  2. Formation of compositional gradient profiles by using shear-induced polymer migration phenomenon under Couette flow field

    Energy Technology Data Exchange (ETDEWEB)

    Im, Sang Hyuk; Lee, Su Jin [Kyung Hee University, Yongin (Korea, Republic of); Suh, Duck Jong; Park, O Ok [Korea Advanced Institute of Science and Technology (KAIST), Daejeon (Korea, Republic of); Kwon, Moo Hyun [Woosuk University, Wanju (Korea, Republic of)

    2015-07-15

    We investigated whether a graded-index profile, specified by the polymer compositional gradient, could be formed using shear-induced polymer migration phenomenon in a polymer solution. For the presented model system, we generated a shear flow by rotating a glass rod at the center of a polystyrene/methylmethacrylate (PS/MMA) solution and measured the degree of polymer migration by the shear flow field by examining the concentration of polymer solution along the radial direction from the rotating axis to the periphery. Through model experiments, we formed a compositional gradient and controlled its profile in the solution by varying the concentration of polymer solution, molecular weight of polymer, and shear rate. Finally, we solidified the gradient profiles by the polymerization of the PS/MMA solution and confirmed that the gradient profiles were maintained with a compositional gradient twice larger than the mother PS/MMA solution.

  3. Sequence stratigraphy of the Raha Formation, Bakr Oil Field, Gulf of Suez, Egypt: Insights from electrical well log and palynological data

    Science.gov (United States)

    Mansour, Ahmed; Mohamed, Omar; Tahoun, Sameh S.; Elewa, Ashraf M. T.

    2018-03-01

    The current paper provides a high resolution sequence stratigraphic study of the Raha Formation from the productive Bakr Oil Field, central Gulf of Suez, Egypt. Sixty cutting rock samples spanning the Cenomanian from three wells (Bakr-114, B-115 and B-109) in the Bakr Basin, were palynologically investigated. The documented palynomorphs assemblage of either terrestrially-derived sporomorphs or marine inhabited dinocysts, allowed two palynological zones as well as their encompassing depositional palaeoenvironment to be recognized. These zones are Afropollis jardinus-Crybelosporites pannuceus Assemblage Zone (early-middle Cenomanian) and Classopollis brasiliensis-Tricolpites sagax Assemblage Zone (late Cenomanian). Detailed analysis of the particulate organic matter compositions suggested that the depositional palaeoenvironment of the Raha Formation was fluctuating between supratidal and distal-inner neritic conditions, due to successive oscillations of the Neo-Tethyan Ocean during the Cenomanian. The pronounced peaks of particulate organic matter versus gamma ray are markedly used in delineating the depositional sequences of the Raha Formation and their bounding surfaces. The Raha Formation probably corresponds to a second-order depositional sequence, which can be further subdivided into eight third-order depositional sequences, of which six are complete and two are incomplete ones. These depositional sequences are significantly synchronized based on a simple 2-D correlation model between the three wells. According to the hierarchical duration system, the Cenomanian herein was approximately attributed to 6 Myr, each of which has lower order depositional sequences that took approximately 0.9 Myr. Based on the sequence stratigraphic approach together with palynofacies analysis and gamma ray data, a condensed section was defined in the B-115.

  4. Large scale obduction of preserved oceanic crust: linking the Lesser Caucasus and NE Anatolian ophiolites and implications for the formation of the Lesser Caucasus-Pontides Arc

    Science.gov (United States)

    Hassig, Marc; Rolland, Yann; Sosson, Marc; Galoyan, Ghazar; Sahakyan, Lilit; Topuz, Gultelin; Farouk Çelik, Omer; Avagyan, Ara; Muller, Carla

    2014-05-01

    Armenia, Mid Ocean Ridge Basalt (MORB) to volcanic arc rocks and Intra-Plate Basalts (IPB). Lithostratigraphic comparisons have shown that the relations between the three units, well identified in the Lesser Caucasus, are similar to those found in NE Anatolia, including the emplacement of stratigraphically conform and discordant deposits. New field data has also shed light on an outcrop of low-grade metamorphic rocks of volcanic origin overthrusted by the ophiolites towards the south on the northern side of the Erzincan basin, along the North Anatolian Fault (NAF). We extend our model for the Lesser Caucasus to NE Anatolia and infer that the missing of the volcanic arc formed above the intra-plate subduction may be explained by its dragging under the obducting ophiolite with scaling by faulting and tectonic erosion. In this large scale model the blueschists of Stepanavan, the garnet amphibolites of Amasia and the metamorphic arc complex of Erzincan correspond to this missing volcanic arc. We propose that the ophiolites of these two zones originate from the same oceanic domain and were emplaced during the same obduction event. This reconstructed ophiolitic nappe represents a preserved non-metamorphic oceanic domain over-thrusting up to 200km of continental domain along more than 500km. Distal outcrops of this exceptional object were preserved from latter collision which was concentrated along the suture zones.

  5. Unpacking the Link between Entrepreneurialism and Employability: An Assessment of the Relationship between Entrepreneurial Attitudes and Likelihood of Graduate Employment in a Professional Field

    Science.gov (United States)

    Bell, Robin

    2016-01-01

    Purpose: The purpose of this paper is to investigate the relationship between students' entrepreneurial attitudes and traits and their classification of employment six months after university graduation. It aims to identify what specific attitudes and traits of entrepreneurial graduates are linked to employability in a professional or managerial…

  6. Estrone sulfate source of estrone and estradiol formation in isolated human hair roots: identification of a pathway linked to hair growth phase and subject to site-, gender-, and age-related modulations.

    Science.gov (United States)

    Wehner, Gabriele; Schweikert, Hans-Udo

    2014-04-01

    The present study investigated the metabolism of estrone sulfate into bioactive estrogens in the human hair root, including the effects of hair growth phase, anatomical site, gender, and age. Healthy male (n = 18) and female (n = 20) subjects were investigated. Growing (anagen) and resting (telogen) hair roots were collected from selected scalp and body sites. Estrone sulfate metabolism in the hair root yielded substantial levels of estrone and estradiol. Estrogen synthesis exceeded that associated with aromatization of androgens in a previous study. In subjects hair was lower in men than in women. Comparable levels of estrogen formation were observed in 1) male and female axillary and pubic hair and 2) male beard hair. These levels were higher than the estrogen levels detected in the in scalp hair of men women. In telogen hair from all body sites, the capacity to form estrone from estrone sulfate remained unaffected, whereas the ability to form estradiol decreased by 62% and 86% in men and women, respectively. Estrogen formation from estrone sulfate in sexually dimorphic hair is linked to the hair growth phase and is subject to gender- and age-related modulations. The magnitude of the in situ estrogen synthesis from estrone sulfate and the selective arrest of estradiol synthesis at the end of the hair cycle suggest that this pathway plays a crucial role in the regulation of human hair growth.

  7. Anti-proliferative effect of extremely low frequency electromagnetic field on preneoplastic lesions formation in the rat liver

    Directory of Open Access Journals (Sweden)

    Villa-Treviño Saúl

    2010-04-01

    Full Text Available Abstract Background Recently, extremely low frequency electromagnetic fields (ELF-EMF have been studied with great interest due to their possible effects on human health. In this study, we evaluated the effect of 4.5 mT - 120 Hz ELF-EMF on the development of preneoplastic lesions in experimental hepatocarcinogenesis. Methods Male Fischer-344 rats were subjected to the modified resistant hepatocyte model and were exposed to 4.5 mT - 120 Hz ELF-EMF. The effects of the ELF-EMF on hepatocarcinogenesis, apoptosis, proliferation and cell cycle progression were evaluated by histochemical, TUNEL assay, caspase 3 levels, immunohistochemical and western blot analyses. Results The application of the ELF-EMF resulted in a decrease of more than 50% of the number and the area of γ-glutamyl transpeptidase-positive preneoplastic lesions (P = 0.01 and P = 0.03, respectively and glutathione S-transferase placental expression (P = 0.01. The number of TUNEL-positive cells and the cleaved caspase 3 levels were unaffected; however, the proliferating cell nuclear antigen, Ki-67, and cyclin D1 expression decreased significantly (P ≤ 0.03, as compared to the sham-exposure group. Conclusion The application of 4.5 mT - 120 Hz ELF-EMF inhibits preneoplastic lesions chemically induced in the rat liver through the reduction of cell proliferation, without altering the apoptosis process.

  8. National implementation of acute stroke care centers in the Veterans Health Administration (VHA): formative evaluation of the field response.

    Science.gov (United States)

    Damush, Teresa M; Miller, Kristine K; Plue, Laurie; Schmid, Arlene A; Myers, Laura; Graham, Glenn; Williams, Linda S

    2014-12-01

    In 2011, the Veterans Health Administration (VHA) released the Acute Ischemic Stroke (AIS) Directive, which mandated reorganization of acute stroke care, including self-designation of stroke centers as Primary (P), Limited Hours (LH), or Supporting (S). In partnership with the VHA Offices of Emergency Medicine and Specialty Care Services, the VA Stroke QUERI conducted a formative evaluation in a national sample of three levels of stroke centers in order to understand barriers and facilitators. The evaluation consisted of a mixed-methods assessment that included a qualitative assessment of data from semi-structured interviews with key informants and a quantitative assessment of stroke quality-of-care data reporting practices by facility characteristics. The final sample included 38 facilities (84 % participation rate): nine P, 24 LH, and five S facilities. In total, we interviewed 107 clinicians and 16 regional Veterans Integrated Service Network (VISN) leaders. Across all three levels of stroke centers, stroke teams identified the specific need for systematic nurse training to triage and initiate stroke protocols. The most frequently reported barriers centered around quality-of-care data collection. A low number of eligible veterans arriving at the VAMC in a timely manner was another major impediment. The LH and S facilities reported some unique barriers: access to radiology and neurology services; EMS diverting stroke patients to nearby stroke centers, maintaining staff competency, and a lack of stroke clinical champions. Solutions that were applied included developing stroke order sets and templates to provide systematic decision support, implementing a stroke code in the facility for a coordinated response to stroke, and staff resource allocation and training. Data reporting by facility evaluation demonstrated that categorizing site volume did indicate a lower likelihood of reporting among VAMCs with 25-49 acute stroke admissions per year. The AIS Directive

  9. The influence of laser scribing on magnetic domain formation in grain oriented electrical steel visualized by directional neutron dark-field imaging

    Science.gov (United States)

    Rauscher, P.; Betz, B.; Hauptmann, J.; Wetzig, A.; Beyer, E.; Grünzweig, C.

    2016-12-01

    The performance and degree of efficiency of transformers are directly determined by the bulk magnetic properties of grain oriented electrical steel laminations. The core losses can be improved by post manufacturing methods, so-called domain refinement techniques. All these methods induce mechanical or thermal stress that refines the domain structure. The most commonly used technique is laser scribing due to the no-contact nature and the ease of integration in existing production systems. Here we show how directional neutron dark-field imaging allows visualizing the impact of laser scribing on the bulk and supplementary domain structure. In particular, we investigate the domain formation during magnetization of samples depending on laser treatment parameters such as laser energy and line distances. The directional dark-field imaging findings were quantitatively interpreted in the context with global magnetic hysteresis measurements. Especially we exploit the orientation sensitivity in the dark-field images to distinguish between different domain structures alignment and their relation to the laser scribing process.

  10. Quasi-adiabatic particle acceleration in a magnetic field reversals and the formation of the plasma sheet boundary layer in the earth's magnetotail

    International Nuclear Information System (INIS)

    Zelenyi, L.M.; Vogin, D.V.; Buechner, J.

    1989-01-01

    Two types of regularity exist for the particle motion in the two-dimensional magnetic field reversals (MFR) with the strongly curves magnetic field lines - the usual adiabatic and another one which we called 'quasiadiabatic'. Here we consider the acceleration of MFR particles in stationary and homogeneous electric field induced by the motion of MFR through the ambient plasma (i.e. solar wind). Assuming that the time scale of acceleration is slow in comparison with the period of orbital motion we introduce the new longitudinal invariant I κ . This enables to describe the process of acceleration in a closed form and to obtain for the first time the laws governing the quasiadiabatic ion acceleration in the Earth's mangetotail. The similarities and differences in adiabatic and quasiadiabatic acceleration mechanisms are discussed. The obtained results give and important insights to the problem of the particle heating in hte Earth's magnetotail and to the formation of accelerated plasma streams along the edges of the plasma sheet. (author). 17 refs.; 7 figs

  11. Crop Rotational Effects on Yield Formation in Current Sugar Beet Production – Results From a Farm Survey and Field Trials

    Directory of Open Access Journals (Sweden)

    Heinz-Josef Koch

    2018-03-01

    Full Text Available In Europe, the framework for sugar beet (Beta vulgaris L. production was subject to considerable changes and for the future it is expected that sugar beet cultivation might concentrate around the sugar factories for economic reasons. Based on data from a national sugar beet farmers’ survey and multi-year crop rotation trials, the effects of cropping interval (number of years in between two subsequent sugar beet crops and of preceding crops on sugar yield were elucidated under current Central European management conditions. The dominating sugar beet cropping interval was ≥4 years in the farm survey with pronounced differences between regions. However, the cropping intervals 2, 3, and ≥4 years did not affect the sugar yield. Therefore, significant differences in sugar yield between regions were assumed to be caused by multiple interactions between year, site, and farmers’ skills. Throughout Germany, the dominating preceding crops in sugar beet cultivation were winter wheat (Triticum aestivum L. and winter barley (Hordeum vulgare L.. In the field trials, the sugar yield was 5% higher after pea (Pisum sativum L. compared to maize (Zea mays L. as preceding crop, while differences between the preceding crops pea and winter wheat, and wheat and maize were not significant. Repeated measurements of canopy development and leaf color during the growing season revealed a higher N-availability after pea as preceding crop. However, decreased growth after maize was not completely compensated for by high N-fertilizer doses. Overall, the causes for the differences in sugar yield between the preceding crops remained open. The results do not support concerns about substantial yield losses in sugar beet production due to a reduction in the cropping interval from 3 to 2 years. Nevertheless, short rotations with maize and sugar beet might increase the risk of Rhizoctonia solani crown and root rot infestation. Leguminous crops such as pea offer the potential

  12. Crop Rotational Effects on Yield Formation in Current Sugar Beet Production – Results From a Farm Survey and Field Trials

    Science.gov (United States)

    Koch, Heinz-Josef; Trimpler, Kerrin; Jacobs, Anna; Stockfisch, Nicol

    2018-01-01

    In Europe, the framework for sugar beet (Beta vulgaris L.) production was subject to considerable changes and for the future it is expected that sugar beet cultivation might concentrate around the sugar factories for economic reasons. Based on data from a national sugar beet farmers’ survey and multi-year crop rotation trials, the effects of cropping interval (number of years in between two subsequent sugar beet crops) and of preceding crops on sugar yield were elucidated under current Central European management conditions. The dominating sugar beet cropping interval was ≥4 years in the farm survey with pronounced differences between regions. However, the cropping intervals 2, 3, and ≥4 years did not affect the sugar yield. Therefore, significant differences in sugar yield between regions were assumed to be caused by multiple interactions between year, site, and farmers’ skills. Throughout Germany, the dominating preceding crops in sugar beet cultivation were winter wheat (Triticum aestivum L.) and winter barley (Hordeum vulgare L.). In the field trials, the sugar yield was 5% higher after pea (Pisum sativum L.) compared to maize (Zea mays L.) as preceding crop, while differences between the preceding crops pea and winter wheat, and wheat and maize were not significant. Repeated measurements of canopy development and leaf color during the growing season revealed a higher N-availability after pea as preceding crop. However, decreased growth after maize was not completely compensated for by high N-fertilizer doses. Overall, the causes for the differences in sugar yield between the preceding crops remained open. The results do not support concerns about substantial yield losses in sugar beet production due to a reduction in the cropping interval from 3 to 2 years. Nevertheless, short rotations with maize and sugar beet might increase the risk of Rhizoctonia solani crown and root rot infestation. Leguminous crops such as pea offer the potential for higher

  13. Field and Satellite Observations of the Formation and Distribution of Arctic Atmospheric Bromine Above a Rejuvenated Sea Ice Cover

    Science.gov (United States)

    Nghiem, Son V.; Rigor, Ignatius G.; Richter, Andreas; Burrows, John P.; Shepson, Paul B.; Bottenheim, Jan; Barber, David G.; Steffen, Alexandra; Latonas, Jeff; Wang, Feiyue; hide

    2012-01-01

    Recent drastic reduction of the older perennial sea ice in the Arctic Ocean has resulted in a vast expansion of younger and saltier seasonal sea ice. This increase in the salinity of the overall ice cover could impact tropospheric chemical processes. Springtime perennial ice extent in 2008 and 2009 broke the half-century record minimum in 2007 by about one million km2. In both years seasonal ice was dominant across the Beaufort Sea extending to the Amundsen Gulf, where significant field and satellite observations of sea ice, temperature, and atmospheric chemicals have been made. Measurements at the site of the Canadian Coast Guard Ship Amundsen ice breaker in the Amundsen Gulf showed events of increased bromine monoxide (BrO), coupled with decreases of ozone (O3) and gaseous elemental mercury (GEM), during cold periods in March 2008. The timing of the main event of BrO, O3, and GEM changes was found to be consistent with BrO observed by satellites over an extensive area around the site. Furthermore, satellite sensors detected a doubling of atmospheric BrO in a vortex associated with a spiral rising air pattern. In spring 2009, excessive and widespread bromine explosions occurred in the same region while the regional air temperature was low and the extent of perennial ice was significantly reduced compared to the case in 2008. Using satellite observations together with a Rising-Air-Parcel model, we discover a topographic control on BrO distribution such that the Alaskan North Slope and the Canadian Shield region were exposed to elevated BrO, whereas the surrounding mountains isolated the Alaskan interior from bromine intrusion.

  14. Regularities in dose field formation for fixation of 252Cf and 60Co sources on the same plane

    International Nuclear Information System (INIS)

    Ivanov, V.N.; Vtyurin, B.M.; Ivanova, L.F.; Kondzhariya, Yu.R.

    1983-01-01

    A computerized study was made of a change in the correlation between the sizes of an irradiated volume and the distribution of sources. Criteria have been established for the utilization of 252 Cf and 60 Co sources of different active length and design placed on the same plane. Reference dose rate and its derivatives have been chosen as the main parameters that characterize a dose field. A dosimetric analysis was performed using the data for an adsorbed dose of neutrons in the tissue, taking account of high RBE of 252 Cf fast neutrons that equals 6-7, and a slight change of the local RBE value near the source resulting from a change of the effective spectrum of neutrons in combination with the growth of a contribution of #betta#-radiation into the summary dose with the removal from the source. The irradiated volume was evaluated by introducing 3 linear parameters - length, thickness and width. It has been shown that the ratio of the length of an irradiated volume to the active length of 252 Cf sources with radionuclide regular linear density changes from 0.7 with the isodose value of 85% up to 0.97 with the isodose value of 60%. For 60 Co sources with a higher linear density of the radionuclide on the edges the lower limit of this value equals 1. Intervals of changes in the rest of parameters have also been defined. The results obtained are presented graphically. The results of the study are used for a dosimetric control of the clinical trials of 252 Cf and 60 Co sources in the treatment of patients with tumors of the tongue, oral cavity fundus, lip and other sites

  15. Formation, characterization and dynamics of onion like carbon structures from nanodiamonds using reactive force-fields for electrical energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Ganesh, Panchapakesan [ORNL; Kent, Paul R [ORNL; Mochalin, Vadym N [ORNL

    2011-01-01

    We simulate the experimentally observed graphitization of nanodiamonds into multi-shell onion-like carbon nanostructures, also called carbon onions, at different temperatures, using reactive force fields. The simulations include long-range Coulomb and van der Waals interactions. Our results suggest that long-range interactions play a crucial role in the phase-stability and the graphitization process. Graphitization is both enthalpically and entropically driven and can hence be controlled with temperature. The outer layers of the nanodiamond have a lower kinetic barrier toward graphitization irrespective of the size of the nanodiamond and graphitize within a few-hundred picoseconds, with a large volume increase. The inner core of the nanodiamonds displays a large size-dependent kinetic barrier, and graphitizes much more slowly with abrupt jumps in the internal energy. It eventually graphitizes by releasing pressure and expands once the outer shells have graphitized. The degree of transformation at a particular temperature is thereby determined by a delicate balance between the thermal energy, long-range interactions, and the entropic/enthalpic free energy gained by graphitization. Upon full graphitization, a multi-shell carbon nanostructure appears, with a shell-shell spacing of about {approx}3.4 {angstrom} for all sizes. The shells are highly defective with predominantly five- and seven-membered rings to curve space. Larger nanodiamonds with a diameter of 4 nm can graphitize into spiral structures with a large ({approx}29-atom carbon ring) pore opening on the outermost shell. Such a large one-way channel is most attractive for a controlled insertion of molecules/ions such as Li ions, water, or ionic liquids, for increased electrochemical capacitor or battery electrode applications.

  16. Formation, characterization, and dynamics of onion-like carbon structures for electrical energy storage from nanodiamonds using reactive force fields

    Energy Technology Data Exchange (ETDEWEB)

    Ganesh, P. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Science; Kent, P. R. C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Science; Mochalin, V. [Drexel Univ., Philadelphia, PA (United States). Dept. of Materials Science and Engineering

    2011-10-01

    We simulate the experimentally observed graphitization of nanodiamonds into multi-shell onion-like carbonnanostructures, also called carbon onions, at different temperatures, using reactive force fields. The simulations include long-range Coulomb and van der Waals interactions. Our results suggest that long-range interactions play a crucial role in the phase-stability and the graphitization process. Graphitization is both enthalpically and entropically driven and can hence be controlled with temperature. The outer layers of the nanodiamond have a lower kinetic barrier toward graphitization irrespective of the size of the nanodiamond and graphitize within a few-hundred picoseconds, with a large volume increase. The inner core of the nanodiamonds displays a large size-dependent kinetic barrier, and graphitizes much more slowly with abrupt jumps in the internal energy. It eventually graphitizes by releasing pressure and expands once the outer shells have graphitized. The degree of transformation at a particular temperature is thereby determined by a delicate balance between the thermal energy, long-range interactions, and the entropic/enthalpic free energy gained by graphitization. Upon full graphitization, a multi-shell carbonnanostructure appears, with a shell-shell spacing of about ~3.4 Å for all sizes. The shells are highly defective with predominantly five- and seven-membered rings to curve space. Larger nanodiamonds with a diameter of 4 nm can graphitize into spiral structures with a large (~29-atom carbon ring) pore opening on the outermost shell. Such a large one-way channel is most attractive for a controlled insertion of molecules/ions such as Li ions, water, or ionic liquids, for increased electrochemical capacitor or battery electrode applications.

  17. Tracing the Mass-Dependent Star Formation History of Late-Type Galaxies using X-ray Emission: Results from the CHANDRA Deep Fields

    Science.gov (United States)

    Lehmer, B.D; Brandt, W.N.; Schneider, D.P.; Steffen, A.T.; Alexander, D.M.; Bell, E.F.; Hornschemeier, A.E.; McIntosh, D.H.; Bauer, F.E.; Gilli, R.; hide

    2008-01-01

    We report on the X-ray evolution over the last approx.9 Gyr of cosmic history (i.e., since z = 1.4) of late-type galaxy populations in the Chandra Deep Field-North and Extended Chandra Deep Field-South (CDF-N and E-CDF-S. respectively; jointly CDFs) survey fields. Our late-type galaxy sample consists of 2568 galaxies. which were identified using rest-frame optical colors and HST morphologies. We utilized X-ray stacking analyses to investigate the X-ray emission from these galaxies, emphasizing the contributions from normal galaxies that are not dominated by active galactic nuclei (AGNs). Over this redshift range, we find significant increases (factors of approx. 5-10) in the X-ray-to-optical mean luminosity ratio (L(sub x)/L(sub B)) and the X-ray-to-stellar-mass mean ratio (L(sub x)/M(sub *)) for galaxy populations selected by L(sub B) and M(sub *), respectively. When analyzing galaxy samples selected via SFR, we find that the mean X-ray-to-SFR ratio (L(sub x)/SFR) is consistent with being constant over the entire redshift range for galaxies with SFR = 1-100 Solar Mass/yr, thus demonstrating that X-ray emission can be used as a robust indicator of star-formation activity out to z approx. 1.4. We find that the star-formation activity (as traced by X-ray luminosity) per unit stellar mass in a given redshift bin increases with decreasing stellar mass over the redshift range z = 0.2-1, which is consistent with previous studies of how star-formation activity depends on stellar mass. Finally, we extend our X-ray analyses to Lyman break galaxies at z approx. 3 and estimate that L(sub x)/L(sub B) at z approx. 3 is similar to its value at z = 1.4.

  18. Link Analysis

    Science.gov (United States)

    Donoho, Steve

    Link analysis is a collection of techniques that operate on data that can be represented as nodes and links. This chapter surveys a variety of techniques including subgraph matching, finding cliques and K-plexes, maximizing spread of influence, visualization, finding hubs and authorities, and combining with traditional techniques (classification, clustering, etc). It also surveys applications including social network analysis, viral marketing, Internet search, fraud detection, and crime prevention.

  19. A Method of Sharing Tacit Knowledge by a Bulletin Board Link to Video Scene and an Evaluation in the Field of Nursing Skill

    Science.gov (United States)

    Shimada, Satoshi; Azuma, Shouzou; Teranaka, Sayaka; Kojima, Akira; Majima, Yukie; Maekawa, Yasuko

    We developed the system that knowledge could be discovered and shared cooperatively in the organization based on the SECI model of knowledge management. This system realized three processes by the following method. (1)A video that expressed skill is segmented into a number of scenes according to its contents. Tacit knowledge is shared in each scene. (2)Tacit knowledge is extracted by bulletin board linked to each scene. (3)Knowledge is acquired by repeatedly viewing the video scene with the comment that shows the technical content to be practiced. We conducted experiments that the system was used by nurses working for general hospitals. Experimental results show that the nursing practical knack is able to be collected by utilizing bulletin board linked to video scene. Results of this study confirmed the possibility of expressing the tacit knowledge of nurses' empirical nursing skills sensitively with a clue of video images.

  20. Are the different gully morphologies due to different formation processes on the Kaiser dune field on Mars?

    Science.gov (United States)

    Pasquon, K.; Gargani, J.; Nachon, M.; Conway, S. J.; Massé, M.; Jouannic, G.; Balme, M. R.; Costard, F.; Vincendon, M.

    2017-12-01

    Diverse gully morphologies are seen on Mars and differences are often neglected for simplification. Here we describe in detail the morphology and present-day activity of two gully-systems on the Kaiser dune field in the southern hemisphere of Mars. We then compare their activity with that of the morphologically distinct linear dune gullies present on the same dunes. The studied gully-systems have large depositional aprons (named "large apron gullies") and occur on dune faces oriented westward. They are active from mid-autumn to late winter (i.e. from Ls 50° to Ls 180°) coinciding with CO2 ice condensation/sublimation cycles. Sandy material collapses from the alcove flanks onto the alcove floor sporadically throughout this period. This accumulated sand is remobilized by punctuated mass flows which we estimate to be up to 7100 m3 in volume. These flows run out on to the apron and occur between Ls 120° and Ls 160°. These mass flow events occur when the number of "digitate flows" is at its seasonal maximum. Digitate flows are characterized by long-narrow zig-zagging low-albedo tracks and do not seem to transport appreciable sediment, and they can number in the hundreds. Small pits appear at their termini or midway along and sometimes these pits are re-deepened by subsequent flows. These events repeat every year and using volume balance calculations we find that the whole system could be built on a timescale of hundreds of martian ears. These large apron gullies differ in morphology and timing from the linear dune gullies. The linear dune gullies are active in late winter, or beginning of spring when the CO2 frost finally sublimates, which occurs after the activity of the large apron gullies. Due to the difference of orientation between large apron gullies and linear dune as well as timing, we infer that insolation, which may influence (i) the depth to ground ice, (ii) the amount of volatiles deposits, is the main cause their differences. Sediment transport by CO2

  1. Modern Processes of Hydrocarbon Migration and Re-Formation of Oil and Gas Fields (Based on the Results of Monitoring and Geochemical Studies)

    Science.gov (United States)

    Plotnikova, Irina; Salakhidinova, Gulmira; Nosova, Fidania; Pronin, Nikita; Ostroukhov, Sergey

    2015-04-01

    Special geochemical studies of oils allowed to allocate a movable migration component of oils in the industrial oil deposits. In the field the migration component of oils varies in different parts of the field. The largest percentage of the light migration component (gas condensate of the oil) was detected in the central part of the Kama-Kinel troughs system. Monitoring of the composition of water, oil and gas (condensate light oil component) in the sedimentary cover and ni crystalline basement led to the conclusion of modern migration of hydrocarbons in sedimentary cover. This proves the existence of the modern processes of formation and reformation of oil and gas fields. This presentation is dedicated to the problem of definition of geochemical criteria of selection of hydrocarbons deposit reformation zone in the sample wells of Minibaevskaya area of Romashkinskoye field. While carrying out this work we examined 11 samples of oil from the Upper Devonian Pashiysky horizon. Four oil samples were collected from wells reckoned among the "anomalous" zones that were marked out according to the results of geophysical, oil field and geological research. Geochemical studies of oils were conducted in the laboratory of geochemistry of the Kazan (Volga-region) Federal University. The wells where the signs of hydrocarbons influx from the deep zones of the crust were recorded are considered to be "anomalous". A number of scientists connect this fact to the hypothesis about periodic influx of deep hydrocarbons to the oil deposits of Romashkinskoye field. Other researchers believe that the source rocks of the adjacent valleys sedimentary cover generate gases when entering the main zone of gas formation, which then migrate up the section and passing through the previously formed deposits of oil, change and "lighten" their composition. Regardless of the point of view on the source of the hydrocarbons, the study of the process of deposits refilling with light hydrocarbons is an

  2. High-throughput phenotyping (HTP) identifies seedling root traits linked to variation in seed yield and nutrient capture in field-grown oilseed rape (Brassica napus L.).

    Science.gov (United States)

    Thomas, C L; Graham, N S; Hayden, R; Meacham, M C; Neugebauer, K; Nightingale, M; Dupuy, L X; Hammond, J P; White, P J; Broadley, M R

    2016-04-06

    Root traits can be selected for crop improvement. Techniques such as soil excavations can be used to screen root traits in the field, but are limited to genotypes that are well-adapted to field conditions. The aim of this study was to compare a low-cost, high-throughput root phenotyping (HTP) technique in a controlled environment with field performance, using oilseed rape (OSR;Brassica napus) varieties. Primary root length (PRL), lateral root length and lateral root density (LRD) were measured on 14-d-old seedlings of elite OSR varieties (n = 32) using a 'pouch and wick' HTP system (∼40 replicates). Six field experiments were conducted using the same varieties at two UK sites each year for 3 years. Plants were excavated at the 6- to 8-leaf stage for general vigour assessments of roots and shoots in all six experiments, and final seed yield was determined. Leaves were sampled for mineral composition from one of the field experiments. Seedling PRL in the HTP system correlated with seed yield in four out of six (r = 0·50, 0·50, 0·33, 0·49;P emergence in three out of five (r = 0·59, 0·22, 0·49;P emergence, general early vigour or yield in the field. Associations between PRL and field performance are generally related to early vigour. These root traits might therefore be of limited additional selection value, given that vigour can be measured easily on shoots/canopies. In contrast, LRD cannot be assessed easily in the field and, if LRD can improve nutrient uptake, then it may be possible to use HTP systems to screen this trait in both elite and more genetically diverse, non-field-adapted OSR. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company.

  3. Field-trip guide to subaqueous volcaniclastic facies in the Ancestral Cascades arc in southern Washington State—The Ohanapecosh Formation and Wildcat Creek beds

    Science.gov (United States)

    Jutzeler, Martin; McPhie, Jocelyn

    2017-06-27

    Partly situated in the idyllic Mount Rainier National Park, this field trip visits exceptional examples of Oligocene subaqueous volcaniclastic successions in continental basins adjacent to the Ancestral Cascades arc. The >800-m-thick Ohanapecosh Formation (32–26 Ma) and the >300-m-thick Wildcat Creek (27 Ma) beds record similar sedimentation processes from various volcanic sources. Both show evidence of below-wave-base deposition, and voluminous accumulation of volcaniclastic facies from subaqueous density currents and suspension settling. Eruption-fed facies include deposits from pyroclastic flows that crossed the shoreline, from tephra fallout over water, and from probable Surtseyan eruptions, whereas re-sedimented facies comprise subaqueous density currents and debris flow deposits.

  4. High-field magnetization curve of random-anisotropy amorphous magnet: Observation of a crossover and link to structural short-range order

    Science.gov (United States)

    Filippi, J.; Amaral, V. S.; Barbara, B.

    1991-08-01

    High-field magnetization curves of the series of amorphous alloys DyxGd1-xNi have been measured up to 15 tesla and interpreted in the framework of the theory of Chudnovsky et al. The results show several features (high-field crossovers, correlation volume of local-anisotropy directions, ferromagnetic correlation length) all consistent with each other and in agreement with theoretical predictions.

  5. High-field magnetization curve of random-anisotropy amorphous magnet: Observation of a crossover and link to structural short-range order

    International Nuclear Information System (INIS)

    Filippi, J.; Amaral, V.S.; Barbara, B.

    1991-01-01

    High-field magnetization curves of the series of amorphous alloys Dy x Gd 1-x Ni have been measured up to 15 tesla and interpreted in the framework of the theory of Chudnovsky et al. The results show several features (high-field crossovers, correlation volume of local-anisotropy directions, ferromagnetic correlation length) all consistent with each other and in agreement with theoretical predictions

  6. Effect of Pulsed Electromagnetic Field on Bone Formation and Lipid Metabolism of Glucocorticoid-Induced Osteoporosis Rats through Canonical Wnt Signaling Pathway

    Directory of Open Access Journals (Sweden)

    Yuan Jiang

    2016-01-01

    Full Text Available Pulsed electromagnetic field (PEMF has been suggested as a promising method alternative to drug-based therapies for treating osteoporosis (OP, but the role of PEMF in GIOP animal models still remains unknown. This study was performed to investigate the effect of PEMF on bone formation and lipid metabolism and further explored the several important components and targets of canonical Wnt signaling pathway in GIOP rats. After 12 weeks of intervention, bone mineral density (BMD level of the whole body increased significantly, serum lipid levels decreased significantly, and trabeculae were thicker in GIOP rats of PEMF group. PEMF stimulation upregulated the mRNA and protein expression of Wnt10b, LRP5, β-catenin, OPG, and Runx2 and downregulated Axin2, PPAR-γ, C/EBPα, FABP4, and Dkk-1. The results of this study suggested that PEMF stimulation can prevent bone loss and improve lipid metabolism disorders in GIOP rats. Canonical Wnt signaling pathway plays an important role in bone formation and lipid metabolism during PEMF stimulation.

  7. Effect of Pulsed Electromagnetic Field on Bone Formation and Lipid Metabolism of Glucocorticoid-Induced Osteoporosis Rats through Canonical Wnt Signaling Pathway

    Science.gov (United States)

    Jiang, Yuan; Gou, Hui; Wang, Sanrong; Zhu, Jiang; Tian, Si; Yu, Lehua

    2016-01-01

    Pulsed electromagnetic field (PEMF) has been suggested as a promising method alternative to drug-based therapies for treating osteoporosis (OP), but the role of PEMF in GIOP animal models still remains unknown. This study was performed to investigate the effect of PEMF on bone formation and lipid metabolism and further explored the several important components and targets of canonical Wnt signaling pathway in GIOP rats. After 12 weeks of intervention, bone mineral density (BMD) level of the whole body increased significantly, serum lipid levels decreased significantly, and trabeculae were thicker in GIOP rats of PEMF group. PEMF stimulation upregulated the mRNA and protein expression of Wnt10b, LRP5, β-catenin, OPG, and Runx2 and downregulated Axin2, PPAR-γ, C/EBPα, FABP4, and Dkk-1. The results of this study suggested that PEMF stimulation can prevent bone loss and improve lipid metabolism disorders in GIOP rats. Canonical Wnt signaling pathway plays an important role in bone formation and lipid metabolism during PEMF stimulation. PMID:26941827

  8. Secondary organic aerosol formation in cloud droplets and aqueous particles (aqSOA: a review of laboratory, field and model studies

    Directory of Open Access Journals (Sweden)

    B. Ervens

    2011-11-01

    Full Text Available Progress has been made over the past decade in predicting secondary organic aerosol (SOA mass in the atmosphere using vapor pressure-driven partitioning, which implies that SOA compounds are formed in the gas phase and then partition to an organic phase (gasSOA. However, discrepancies in predicting organic aerosol oxidation state, size and product (molecular mass distribution, relative humidity (RH dependence, color, and vertical profile suggest that additional SOA sources and aging processes may be important. The formation of SOA in cloud and aerosol water (aqSOA is not considered in these models even though water is an abundant medium for atmospheric chemistry and such chemistry can form dicarboxylic acids and "humic-like substances" (oligomers, high-molecular-weight compounds, i.e. compounds that do not have any gas phase sources but comprise a significant fraction of the total SOA mass. There is direct evidence from field observations and laboratory studies that organic aerosol is formed in cloud and aerosol water, contributing substantial mass to the droplet mode.

    This review summarizes the current knowledge on aqueous phase organic reactions and combines evidence that points to a significant role of aqSOA formation in the atmosphere. Model studies are discussed that explore the importance of aqSOA formation and suggestions for model improvements are made based on the comprehensive set of laboratory data presented here. A first comparison is made between aqSOA and gasSOA yields and mass predictions for selected conditions. These simulations suggest that aqSOA might contribute almost as much mass as gasSOA to the SOA budget, with highest contributions from biogenic emissions of volatile organic compounds (VOC in the presence of anthropogenic pollutants (i.e. NOx at high relative humidity and cloudiness. Gaps in the current understanding of aqSOA processes are discussed and further studies (laboratory, field, model

  9. The CMS Experiment: on and under Ground Motions of Structures Due to the Magnetic Field Forces as Observed by the Link Alignment System

    International Nuclear Information System (INIS)

    Alberdi, J.; Arce, J.; Barcala, J. M.; Calvo, E.; Ferrando, A.; Josa, M. I.; Molinero, A.; Navarrete, J.; Oller, J. C.; Yuste, C.; Brochero, J.; Calderon, A.; Fernandez, M. G.; Gomez, G.; Gonzalez-Sanchez, F. J.; Martinez-Ribero, C.; Matorras, F.; Rodrigo, T.; Rui-Arbol, P.; Scodellaro, L.; Sobron, M.; Vila, I.; Virto, A. L.; Fernandez, J.

    2010-01-01

    This document describes results obtained from the Link Alignment System data recorded during the CMS Magnet Test (at SX5 on ground Hall) and the CRAFT08 and 09 periods data taking in the point P5 (UX5), 100 m underground. A brief description of the system is followed by the discussion of the detected relative displacements (from micrometres to centimetres) between detector elements and rotation of detector structures (from microradiants to milliradiants). Observed motions are studied as functions of the magnetic fi eld intensity. Comparisons between recorded data on and under ground are made. (Author) 23 refs.

  10. The CMS Experiment: on and under Ground Motions of Structures Due to the Magnetic Field Forces as Observed by the Link Alignment System

    Energy Technology Data Exchange (ETDEWEB)

    Alberdi, J.; Arce, J.; Barcala, J. M.; Calvo, E.; Ferrando, A.; Josa, M. I.; Molinero, A.; Navarrete, J.; Oller, J. C.; Yuste, C.; Brochero, J.; Calderon, A.; Fernandez, M. G.; Gomez, G.; Gonzalez-Sanchez, F. J.; Martinez-Ribero, C.; Matorras, F.; Rodrigo, T.; Rui-Arbol, P.; Scodellaro, L.; Sobron, M.; Vila, I.; Virto, A. L.; Fernandez, J.

    2010-05-01

    This document describes results obtained from the Link Alignment System data recorded during the CMS Magnet Test (at SX5 on ground Hall) and the CRAFT08 and 09 periods data taking in the point P5 (UX5), 100 m underground. A brief description of the system is followed by the discussion of the detected relative displacements (from micrometres to centimetres) between detector elements and rotation of detector structures (from microradiants to milliradiants). Observed motions are studied as functions of the magnetic fi eld intensity. Comparisons between recorded data on and under ground are made. (Author) 23 refs.

  11. Linked Ocean Data

    Science.gov (United States)

    Leadbetter, Adam; Arko, Robert; Chandler, Cynthia; Shepherd, Adam

    2014-05-01

    "Linked Data" is a term used in Computer Science to encapsulate a methodology for publishing data and metadata in a structured format so that links may be created and exploited between objects. Berners-Lee (2006) outlines the following four design principles of a Linked Data system: Use Uniform Resource Identifiers (URIs) as names for things. Use HyperText Transfer Protocol (HTTP) URIs so that people can look up those names. When someone looks up a URI, provide useful information, using the standards (Resource Description Framework [RDF] and the RDF query language [SPARQL]). Include links to other URIs so that they can discover more things. In 2010, Berners-Lee revisited his original design plan for Linked Data to encourage data owners along a path to "good Linked Data". This revision involved the creation of a five star rating system for Linked Data outlined below. One star: Available on the web (in any format). Two stars: Available as machine-readable structured data (e.g. An Excel spreadsheet instead of an image scan of a table). Three stars: As two stars plus the use of a non-proprietary format (e.g. Comma Separated Values instead of Excel). Four stars: As three stars plus the use of open standards from the World Wide Web Commission (W3C) (i.e. RDF and SPARQL) to identify things, so that people can point to your data and metadata. Five stars: All the above plus link your data to other people's data to provide context Here we present work building on the SeaDataNet common vocabularies served by the NERC Vocabulary Server, connecting projects such as the Rolling Deck to Repository (R2R) and the Biological and Chemical Oceanography Data Management Office (BCO-DMO) and other vocabularies such as the Marine Metadata Interoperability Ontology Register and Repository and the NASA Global Change Master Directory to create a Linked Ocean Data cloud. Publishing the vocabularies and metadata in standard RDF XML and exposing SPARQL endpoints renders them five-star Linked

  12. Operative links

    DEFF Research Database (Denmark)

    Wistoft, Karen

    2010-01-01

    and have been the object of great expectations concerning the ability to incorporate health concerns into every welfare area through health promotion strategies. The paper draws on results and analyses of a collective research project funded by the Danish National Research Council and carried out...... as networks: second, a semantic perspective on discourses and concepts of health, and, third, a health pedagogical perspective on participation, intervention, and roles. This paper argues for the importance of 'operative links' between different levels in health strategies. It is proposed that such links...

  13. Operative Links

    DEFF Research Database (Denmark)

    Wistoft, Karen; Højlund, Holger

    2012-01-01

    and have been the object of great expectations concerning the ability to incorporate health concerns into every welfare area through health promotion strategies. The paper draws on results and analyses of a collective research project funded by the Danish National Research Council and carried out...... links' that indicate cooperative levels which facilitate a creative and innovative effort in disease prevention and health promotion targeted at children and adolescents - across traditional professional boundaries. It is proposed that such links are supported by network structures, shared semantics...

  14. Paleomorphology of the upper part of the Macae formation, Namorado field, Campos basin; Paleomorfologia do intervalo superior da formacao Macae, Campo de Namorado, Bacia de Campos

    Energy Technology Data Exchange (ETDEWEB)

    Barboza, Eduardo Guimaraes [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Inst. de Geociencias. Programa de Pos-Graduacao em Geociencias; Tomazelli, Luiz Jose; Ayup-Zouain, Ricardo Norberto [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Inst. de Geociencias. Centro de Estudos de Geologia Costeira e Oceanica; Viana, Adriano Roessler [PETROBRAS, Rio de Janeiro, RJ (Brazil). Exploracao e Producao. Edificio Sede

    2004-07-01

    The Macae Formation (Late Albian-Turonian of the Campos Basin) is represented by a thick column of carbonate sediments whose deposition began soon after the evaporitic phase that marks the beginning of the marine occupation of the basin. The top of this interval is represented by an unconformity (Type I), indicative of a variation in the base level of the basin, on which the turbidities of the basal sequence of the Namorado Field were deposited. For a better understanding of the depositional geometry of these turbidities, the paleogeomorphology analysis demonstrated to be quite efficient. The method of work used for so was a combination among the seismic 3D visualization (VoxelGeo{sup R}), from the characterization of different physical attributes of the seismic signal, and the facies analysis of wells profiles of the referred field. The developed analysis allowed the individualization and the three-dimensional visualization of a sinuous paleochannel in the top of the interval, until then not described in previous interpretations of this depositional system. With the information coming from this study, a better understanding of the genesis of this accumulation can be reached, especially in the part regarding to the units of important economic character, represented by the turbidities deposits and whose occurrences are related with stages of relative lowering of the sea level. (author)

  15. Delineating chalk sand distribution of Ekofisk formation using probabilistic neural network (PNN) and stepwise regression (SWR): Case study Danish North Sea field

    Science.gov (United States)

    Haris, A.; Nafian, M.; Riyanto, A.

    2017-07-01

    Danish North Sea Fields consist of several formations (Ekofisk, Tor, and Cromer Knoll) that was started from the age of Paleocene to Miocene. In this study, the integration of seismic and well log data set is carried out to determine the chalk sand distribution in the Danish North Sea field. The integration of seismic and well log data set is performed by using the seismic inversion analysis and seismic multi-attribute. The seismic inversion algorithm, which is used to derive acoustic impedance (AI), is model-based technique. The derived AI is then used as external attributes for the input of multi-attribute analysis. Moreover, the multi-attribute analysis is used to generate the linear and non-linear transformation of among well log properties. In the case of the linear model, selected transformation is conducted by weighting step-wise linear regression (SWR), while for the non-linear model is performed by using probabilistic neural networks (PNN). The estimated porosity, which is resulted by PNN shows better suited to the well log data compared with the results of SWR. This result can be understood since PNN perform non-linear regression so that the relationship between the attribute data and predicted log data can be optimized. The distribution of chalk sand has been successfully identified and characterized by porosity value ranging from 23% up to 30%.

  16. Impact of low-frequency pulsed electromagnetic fields and interference currents in the formation of heterotopic ossification after total hip instalation in the hip joint

    Directory of Open Access Journals (Sweden)

    Ivković S.

    2015-01-01

    Full Text Available Due to the extension of life expectancy, the number of elderly people increases, and thus the number of disease and injuries of the locomotor system, especially the hip joint. One of the persistent trend is an increasing trend in the number of patients with coxarthrosis and implanted total hip endoprosthesis. One of the postoperative complications that occurred after implantation a total hip endoprosthesis is heterotopic ossification (HO. HO is the most common complication that occurs after the implantation a total hip endoprosthesis with recorded cases in the range of 9-90%. HO are insufficiently understood phenomenon, which is characterized by the formation of bone in periarticular tissues. We prospectively followed patients who implanted total hip endoprostheses in the department of orthopedics ZC in Kos. Mitrovica in 2008. and 2009. year. We examined the influence of physical agents on the prevention of HO near the hip joint. In these patients the treatment was carried out kinesiotherapeutic at the Center for Rehabilitation Health Center Kosovska Mitrovica, as well as pulse therapy low frequency magnetic field frequency of 30 Hz, 30 minutes, 8 mT intensity and 15 minutes interferential current, 0-100 Hz frequency. All patients were on the rehabilitation of one month (20 days. Based on this research we confirmed the assumption that the use of low frequency pulsed magnetic fields, interference currents and kinesitherapy prevents HO in patients after implantation of total endoprosthesis of the hip joint.

  17. Linking Signatures of Accretion with Magnetic Field Measurements–Line Profiles are not Significantly Different in Magnetic and Non-magnetic Herbig Ae/Be Stars

    Science.gov (United States)

    Reiter, Megan; Calvet, Nuria; Thanathibodee, Thanawuth; Kraus, Stefan; Cauley, P. Wilson; Monnier, John; Rubinstein, Adam; Aarnio, Alicia; Harries, Tim J.

    2018-01-01

    Herbig Ae/Be stars are young, pre-main-sequence stars that sample the transition in structure and evolution between low- and high-mass stars, providing a key test of accretion processes in higher-mass stars. Few Herbig Ae/Be stars have detected magnetic fields, calling into question whether the magnetospheric accretion paradigm developed for low-mass stars can be scaled to higher masses. We present He I 10830 Å line profiles for 64 Herbig Ae/Be stars with a magnetic field measurement in order to test magnetospheric accretion in the physical regime where its efficacy remains uncertain. Of the five stars with a magnetic field detection, one shows redshifted absorption, indicative of infall, and two show blueshifted absorption, tracing mass outflow. The fraction of redshifted and blueshifted absorption profiles in the non-magnetic Herbig Ae/Be stars is remarkably similar, suggesting that the stellar magnetic field does not affect gas kinematics traced by He I 10830 Å. Line profile morphology does not correlate with the luminosity, rotation rate, mass accretion rate, or disk inclination. Only the detection of a magnetic field and a nearly face-on disk inclination show a correlation (albeit for a few sources). This provides further evidence for weaker dipoles and more complex field topologies as stars develop a radiative envelope. The small number of magnetic Herbig Ae/Be stars has already called into question whether magnetospheric accretion can be scaled to higher masses; accretion signatures are not substantially different in magnetic Herbig Ae/Be stars, casting further doubt that they accrete in the same manner as classical T Tauri stars.

  18. Formation and subdivision of the head field in the centipede Strigamia maritima, as revealed by the expression of head gap gene orthologues and hedgehog dynamics

    Directory of Open Access Journals (Sweden)

    Vera S. Hunnekuhl

    2017-10-01

    Full Text Available Abstract Background There have been few studies of head patterning in non-insect arthropods, and even in the insects, much is not yet understood. In the fly Drosophila three head gap genes, orthodenticle (otd, buttonhead (btd and empty spiracles (ems are essential for patterning the head. However, they do not act through the same pair-rule genes that pattern the trunk from the mandibular segment backwards. Instead they act through the downstream factors collier (col and cap‘n’collar (cnc, and presumably other unknown factors. In the beetle Tribolium, these same gap and downstream genes are also expressed during early head development, but in more restricted domains, and some of them have been shown to be of minor functional importance. In the spider Parasteatoda tepidariorum, hedgehog (hh and otd have been shown to play an important role in head segmentation. Results We have investigated the expression dynamics of otx (otd, SP5/btd, ems, and the downstream factors col, cnc and hh during early head development of the centipede Strigamia maritima. Our results reveal the process of head condensation and show that the anteroposterior sequence of specific gene expression is conserved with that in insects. SP5/btd and otx genes are expressed prior to and during head field formation, whereas ems is not expressed until after the initial formation of the head field, in an emerging gap between SP5/btd and otx expression. Furthermore, we observe an early domain of Strigamia hh expression in the head field that splits to produce segmental stripes in the ocular, antennal and intercalary segments. Conclusions The dynamics of early gene expression in the centipede show considerable similarity with that in the beetle, both showing more localised expression of head gap genes than occurs in the fly. This suggests that the broad overlapping domains of head gap genes observed in Drosophila are derived in this lineage. We also suggest that the splitting of the

  19. Formation and subdivision of the head field in the centipede Strigamia maritima, as revealed by the expression of head gap gene orthologues and hedgehog dynamics.

    Science.gov (United States)

    Hunnekuhl, Vera S; Akam, Michael

    2017-01-01

    There have been few studies of head patterning in non-insect arthropods, and even in the insects, much is not yet understood. In the fly Drosophila three head gap genes, orthodenticle ( otd ), buttonhead ( btd ) and empty spiracles ( ems ) are essential for patterning the head. However, they do not act through the same pair-rule genes that pattern the trunk from the mandibular segment backwards. Instead they act through the downstream factors collier ( col ) and cap ' n ' collar ( cnc ), and presumably other unknown factors. In the beetle Tribolium , these same gap and downstream genes are also expressed during early head development, but in more restricted domains, and some of them have been shown to be of minor functional importance. In the spider Parasteatoda tepidariorum , hedgehog ( hh ) and otd have been shown to play an important role in head segmentation. We have investigated the expression dynamics of otx ( otd ), SP5 / btd , ems , and the downstream factors col , cnc and hh during early head development of the centipede Strigamia maritima . Our results reveal the process of head condensation and show that the anteroposterior sequence of specific gene expression is conserved with that in insects. SP5 / btd and otx genes are expressed prior to and during head field formation, whereas ems is not expressed until after the initial formation of the head field, in an emerging gap between SP5 / btd and otx expression. Furthermore, we observe an early domain of Strigamia hh expression in the head field that splits to produce segmental stripes in the ocular, antennal and intercalary segments. The dynamics of early gene expression in the centipede show considerable similarity with that in the beetle, both showing more localised expression of head gap genes than occurs in the fly. This suggests that the broad overlapping domains of head gap genes observed in Drosophila are derived in this lineage. We also suggest that the splitting of the early hh segmental stripes

  20. Covalently linked immunomagnetic separation/adenosine triphosphate technique (Cov-IMS/ATP) enables rapid, in-field detection and quantification of Escherichia coli and Enterococcus spp. in freshwater and marine environments.

    Science.gov (United States)

    Lee, C M; Griffith, J F; Kaiser, W; Jay, J A

    2010-07-01

    Developing a rapid method for detection of faecal pollution is among the critical goals set forth by the Environmental Protection Agency in its revision of water quality criteria. The purpose of this study is to devise and test covalently linked antibody-bead complexes for faecal indicator bacteria (FIB), specifically Escherichia coli or Enterococcus spp., in measuring water quality in freshwater and marine systems. Covalently linked complexes were 58-89% more robust than antibody-bead complexes used in previous studies. Freshwater and marine water samples analysed using covalently linked immunomagnetic separation/adenosine triphosphate quantification technique (Cov-IMS/ATP) and culture-based methods yielded good correlations for E. coli (R = 0·87) and Enterococcus spp. (R = 0·94), with method detection limits below EPA recreational water quality health standards for single standard exceedances (E. coli- 38 cells per 100 ml; Enterococcus spp. - 25 cells per 100 ml). Cov-IMS/ATP correctly classified 87% of E. coli and 94% of Enterococcus spp. samples based on these water quality standards. Cov-IMS/ATP was also used as a field method to rapidly distinguish differential loading of E. coli between two stream channels to their confluence. Cov-IMS/ATP is a robust, in-field detection method for determining water quality of both fresh and marine water systems as well as differential loading of FIB from two converging channels. To our knowledge, this is the first work to present a viable rapid, in-field assay for measuring FIB concentrations in marine water environments. Cov-IMS/ATP is a potential alternative detection method, particularly in areas with limited laboratory support and resources, because of its increased economy and portability. © 2010 The Authors. Journal compilation © 2010 The Society for Applied Microbiology.

  1. Electro-facies analysis of the Sarvak Formation (Middle Cretaceous) and compliance with sedimentary micro facies in an oil field, SW Iran

    International Nuclear Information System (INIS)

    Eghbalkiani, Z.; Goli, T.; Jalilian, A. H.; Kadkhodaie, R.

    2016-01-01

    Electro-facies analysis is a sure method in clustering petrophysical logs analysis that can well indicates the changes of geologic characteristic's of the different lithostratigraphic units as well. Petrographic studies of 120 prepared thin sections of the upper parts of the Sarvak Formation in studied oil field, Southwestern Iran, has resulted in definition of 6 micro facies sedimentary types. These data suggested that the middle Creataceous sediments in the studied area were predominantly deposited in two subenviornments of patch organic barrier and lagoon corresponding to inner and shallow a homoclinal ramp. In addition, using petrophysical logs in the studied well, 10 electrical facies were determined. By analyzing the data petrophysical in Geology software, 10 electrical facies were optimized and then their number was reduced to six. According to good adaptation of optimized electrical facies with sedimentary micro facies, we would generalized obtained dresults to all parts of the Sarvak Formation. Study of porosity changes in the electrical diagrams such as CGR corrected Gamma, and sonic curves in mentioned well, indicated a significant reduction in facies porosity of 1 to 6. In addition, the results showed that the reservoir quality reduction in studied micro facies is corresponded to Bioclastic Rudist debris floatstone/ Rudstone, Benthic foraminifera Rudist debris wackestone / packstone, Benthic Foraminifera peloid Grainstone/Packstone, with High diversity benthic foraminifera wackestone / packstone, Peloid bioclastic wackestone /packstone with Low diversity benthic Foraminifera and Mudestone/Wackestone, respectively. In this study, we concluded that comparison and correlation sedimentary facies with electric microfacies provide an efficient method to study the quality of the hydrocarbon reservoir system that especially can be used in other wells with no core.

  2. Operative Links

    DEFF Research Database (Denmark)

    Wistoft, Karen; Højlund, Holger

    2012-01-01

    educational approaches. Methods: Mixed qualitative design: survey based on telephone interviews with health managers (n=72), personal and focus group interviews with health professionals (n=84) and pupils (n=108) from 18 school classes, and comparative case studies in five selected municipalities of various...... educational goals, learning content, or value clarification. Health pedagogy is often a matter of retrospective rationalization rather than the starting point of planning. Health and risk behaviour approaches override health educational approaches. Conclusions: Operational links between health education...

  3. Potential of energy harvesting in barium titanate based laminates from room temperature to cryogenic/high temperatures: measurements and linking phase field and finite element simulations

    Science.gov (United States)

    Narita, Fumio; Fox, Marina; Mori, Kotaro; Takeuchi, Hiroki; Kobayashi, Takuya; Omote, Kenji

    2017-11-01

    This paper studies the energy harvesting characteristics of piezoelectric laminates consisting of barium titanate (BaTiO3) and copper (Cu) from room temperature to cryogenic/high temperatures both experimentally and numerically. First, the output voltages of the piezoelectric BaTiO3/Cu laminates were measured from room temperature to a cryogenic temperature (77 K). The output power was evaluated for various values of load resistance. The results showed that the maximum output power density is approximately 2240 nW cm‑3. The output voltages of the BaTiO3/Cu laminates were also measured from room temperature to a higher temperature (333 K). To discuss the output voltages of the BaTiO3/Cu laminates due to temperature changes, phase field and finite element simulations were combined. A phase field model for grain growth was used to generate grain structures. The phase field model was then employed for BaTiO3 polycrystals, coupled with the time-dependent Ginzburg–Landau theory and the oxygen vacancies diffusion, to calculate the temperature-dependent piezoelectric coefficient and permittivity. Using these properties, the output voltages of the BaTiO3/Cu laminates from room temperature to both 77 K and 333 K were analyzed by three dimensional finite element methods, and the results are presented for several grain sizes and oxygen vacancy densities. It was found that electricity in the BaTiO3 ceramic layer is generated not only through the piezoelectric effect caused by a thermally induced bending stress but also by the temperature dependence of the BaTiO3 piezoelectric coefficient and permittivity.

  4. Self-consistent modeling of entangled network strands and linear dangling structures in a single-strand mean-field slip-link model

    DEFF Research Database (Denmark)

    Jensen, Mette Krog; Khaliullin, Renat; Schieber, Jay D.

    2012-01-01

    knowledge about the effect of dangling ends and soluble structures. To interpret our recent experimental results, we exploit a molecular model that can predict LVE data and non-linear stress–strain data. The slip-link model has proven to be a robust tool for both LVE and non-linear stress–strain predictions...... strands in the ensemble are attached to the network in both ends. Next we add dangling strands to the network representing the stoichiometric imbalance, or imperfections during curing. By considering monodisperse network strands without dangling ends, we find that the relative low-frequency plateau, G0/GN......0G0G0N, decreases linearly with the average number of entanglements. The decrease from GN0G0N to G 0 is a result of monomer fluctuations between entanglements, which is similar to “longitudinal modes” in tube theory. It is found that the slope of G′ is dependent on the fraction of network strands...

  5. Field estimation of the flock-level diagnostic specificity of an enzyme-linked immunosorbent assay for Avian metapneumovirus antibodies in turkeys.

    Science.gov (United States)

    Muñoz-Zanzi, Claudia; Trampel, Darrell; Hanson, Tim; Harrison, Kristen; Goyal, Sagar; Cortinas, Roberto; Lauer, Dale

    2009-03-01

    Routine serologic testing for Avian metapneumovirus (AMPV) infection of turkey flocks at slaughter is currently being used to monitor changes in the occurrence of AMPV infection in endemic areas and can also be used to detect the emergence of infection in currently unaffected areas. Because of the costs associated with false-positive results, particularly in areas that are free of AMPV infection, there is a need to obtain improved estimates of flock-level specificity (SP). The objective of this study was to estimate flock-level SP of a program to monitor AMPV infection in turkey flocks at processing using a standard enzyme-linked immunosorbent assay (ELISA). A study was carried out in which 37 AMPV-free flocks from 7 Midwest operations were followed serologically. Six percent, 3%, and 0.2% of total samples tested AMPV positive at 8 weeks, 12 weeks, and at processing, respectively. Overall, flock-level SP increased as the cutoff increased and as age increased. Flock-level SP at processing was 97%, if a cutoff of 1 was used (the flock was classified as positive if at least 1 sample tested positive), and 100%, if any other cutoff was used. Administration of antibiotics (P = 0.02) and vaccination for Bordetella avium (P = 0.08) were positively associated with the probability of (false) positive test results. These findings suggest possible cross-reactions with other infections and highlight the need to consider variable diagnostic performance depending on farm conditions.

  6. Extremely Low-Frequency Magnetic Fields and Redox-Responsive Pathways Linked to Cancer Drug Resistance: Insights from Co-Exposure-Based In Vitro Studies

    Directory of Open Access Journals (Sweden)

    Stefano Falone

    2018-02-01

    Full Text Available Electrical devices currently used in clinical practice and common household equipments generate extremely low-frequency magnetic fields (ELF-MF that were classified by the International Agency for Research on Cancer as “possible carcinogenic.” Assuming that ELF-MF plays a role in the carcinogenic process without inducing direct genomic alterations, ELF-MF may be involved in the promotion or progression of cancers. In particular, ELF-MF-induced responses are suspected to activate redox-responsive intracellular signaling or detoxification scavenging systems. In fact, improved protection against oxidative stress and redox-active xenobiotics is thought to provide critical proliferative and survival advantage in tumors. On this basis, an ever-growing research activity worldwide is attempting to establish whether tumor cells may develop multidrug resistance through the activation of essential cytoprotective networks in the presence of ELF fields, and how this might trigger relevant changes in tumor phenotype. This review builds a framework around how the activity of redox-responsive mediators may be controlled by co-exposure to ELF-MF and reactive oxygen species-generating agents in tumor and cancer cells, in order to clarify whether and how such potential molecular targets could help to minimize or neutralize the functional interaction between ELF-MF and malignancies.

  7. Composition and Formation of Gabbro-Peridotite Hosted Seafloor Massive Sulfide Deposits from the Ashadze-1 Hydrothermal Field, Mid-Atlantic Ridge

    Directory of Open Access Journals (Sweden)

    Anna Firstova

    2016-03-01

    Full Text Available This paper presents mineralogical and geochemical data on seafloor massive sulfides (SMS from the Ashadze-1 hydrothermal field at the Mid-Atlantic Ridge (MAR. The Ashadze-1 deposit is associated with the uplifted lower crust and upper mantle (oceanic core complex, OCC of the MAR segment characterized by asymmetric mode of accretion. The OCC is represented by deep-seated gabbro-peridotite rocks exhumed on the rift valley slope along the detachment fault, during seafloor spreading. Hydrothermal processes in OCC environments result in different deposit composition and morphology compared to basalt-hosted systems. Abundant chimneys and enrichment in particular metals, including copper, zinc, gold, cobalt and tin are typical for this type of SMS deposit. The Ashadze-1 deposit is considered an example of a hydrothermal system in the initial stage of evolution marked by the young age of the sulfides (<7.2 kyr. The mineralogy of Ashadze-1 reflects primary ore-forming processes unaffected by post formation alteration. We propose a model for the primary ore-forming hydrothermal process in an ultramafic-hosted environment on the modern seafloor.

  8. Differential intensity-dependent effects of pulsed electromagnetic fields on RANKL-induced osteoclast formation, apoptosis, and bone resorbing ability in RAW264.7 cells.

    Science.gov (United States)

    Wang, Pan; Liu, Juan; Yang, Yuefan; Zhai, Mingming; Shao, Xi; Yan, Zedong; Zhang, Xuhui; Wu, Yan; Cao, Lu; Sui, Bingdong; Luo, Erping; Jing, Da

    2017-12-01

    Pulsed electromagnetic fields (PEMF) have been proven to be effective for promoting bone mass and regulating bone turnover both experimentally and clinically. However, the exact mechanisms for the regulation of PEMF on osteoclastogenesis as well as optical exposure parameters of PEMF on inhibiting osteoclastic activities and functions remain unclear, representing significant limitations for extensive scientific application of PEMF in clinics. In this study, RAW264.7 cells incubated with RANKL were exposed to 15 Hz PEMF (2 h/day) at various intensities (0.5, 1, 2, and 3 mT) for 7 days. We demonstrate that bone resorbing capacity was significantly decreased by 0.5 mT PEMF mainly by inhibiting osteoclast formation and maturation, but enhanced at 3 mT by promoting osteoclast apoptosis. Moreover, gene expression of RANK, NFATc1, TRAP, CTSK, BAX, and BAX/BCL-2 was significantly decreased by 0.5 mT PEMF, but increased by 3 mT. Our findings reveal a significant intensity window for low-intensity PEMF in regulating bone resorption with diverse nature for modulating osteoclastogenesis and apoptosis. This study not only enriches our basic knowledge for the regulation of PEMF in osteoclastogenesis, but also may lead to more efficient and scientific clinical application of PEMF in regulating bone turnover and inhibiting osteopenia/osteoporosis. Bioelectromagnetics. 38:602-612, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  9. Shrub mound formation and stability on semi-arid slopes in the Northern Negev Desert of Israel: A field and simulation study

    NARCIS (Netherlands)

    Buis, E.; Temme, A.J.A.M.; Veldkamp, A.; Boeken, B.; Jongmans, A.G.; Breemen, van N.; Schoorl, J.M.

    2010-01-01

    In semi-arid areas vegetation is scarce and often dominated by individual shrubs on raised mounds. The processes of formation of these mounds are diverse and still debated. Often, shrub mound formation is directly related to the formation of vegetation patterns, thereby assuming that shrub mound

  10. Tutorat en ligne et création d'un espace formatif E-tutoring: how to design a formative field

    Directory of Open Access Journals (Sweden)

    Jean-François Bourdet

    2007-03-01

    Full Text Available Cette conférence traite de la construction en ligne d'un espace formatif. Nous entendons par là la représentation et la mise en œuvre par les usagers d'un dispositif de formation en ligne, d'une conception de celui-ci permettant d'en saisir et d'en interpréter les buts, d'en dégager les implications en termes d'attitudes d'apprentissage, de modes d'échanges, d'interactions au sens le plus large. Dans cette perspective, le tutorat comme fonction formative se caractérise par l'exercice de rôles variés et parfois contradictoires (empathie paritaire / validation d'étapes, guidage général / adaptation aux spécificités. Une conséquence est alors l'exigence de distribution de ces rôles sur des acteurs différents, tant humains (tutorat statutaire exercé par une enseignant ou paritaire dans un groupe en formation que logiciels (agents de type compagnon voués à des rôles d'alertes et de propositions d'activités contextualisées par exemple. L'hypothèse est qu'un tel partage contribue à valider l'"ouverture" d'une formation et ce d'autant plus qu'il est conçu de manière à pouvoir évoluer au fil des échanges en ligne. On présentera donc les concepts clés de cette problématique : conception et développement des dispositifs, espace de communication, fonctionnalités offertes par les environnements, outils dédiés au tutorat, afin de mettre en évidence la spécificité de telles situations éducatives.The main goal of the paper is to provide an insight concerning a specific field of research in On line learning. Beside teaching devices design (program, tutoring, tools, we have to think on which way users develop a system representation including conception of the tasks, interactions with others users (students, tutors and interpretation of user's actions by him(herself.This paper suggests that an important part of On line learning experience is the building (design of a virtual space of communication where any user implant

  11. Promising Links between Meditation and Reduced (Brain Aging: An Attempt to Bridge Some Gaps between the Alleged Fountain of Youth and the Youth of the Field

    Directory of Open Access Journals (Sweden)

    Florian Kurth

    2017-05-01

    Full Text Available Over the last decade, an increasing number of studies has reported a positive impact of meditation on cerebral aging. However, the underlying mechanisms for these seemingly brain-protecting effects are not well-understood. This may be due to the fact, at least partly, that systematic empirical meditation research has emerged only recently as a field of scientific scrutiny. Thus, on the one hand, critical questions remain largely unanswered; and on the other hand, outcomes of existing research require better integration to build a more comprehensive and holistic picture. In this article, we first review theories and mechanisms pertaining to normal (brain aging, specifically focusing on telomeres, inflammation, stress regulation, and macroscopic brain anatomy. Then, we summarize existing research integrating the developing evidence suggesting that meditation exerts positive effects on (brain aging, while carefully discussing possible mechanisms through which these effects may be mediated.

  12. Genesis of nanostructured, magnetically tunable ceramics from the pyrolysis of cross-linked polyferrocenylsilane networks and formation of shaped macroscopic objects and micron scale patterns by micromolding inside silicon wafers.

    Science.gov (United States)

    Ginzburg, Madlen; MacLachlan, Mark J; Yang, San Ming; Coombs, Neil; Coyle, Thomas W; Raju, Nandyala P; Greedan, John E; Herber, Rolfe H; Ozin, Geoffrey A; Manners, Ian

    2002-03-20

    The ability to form molded or patterned metal-containing ceramics with tunable properties is desirable for many applications. In this paper we describe the evolution of a ceramic from a metal-containing polymer in which the variation of pyrolysis conditions facilitates control of ceramic structure and composition, influencing magnetic and mechanical properties. We have found that pyrolysis under nitrogen of a well-characterized cross-linked polyferrocenylsilane network derived from the ring-opening polymerization (ROP) of a spirocyclic [1]ferrocenophane precursor gives shaped macroscopic magnetic ceramics consisting of alpha-Fe nanoparticles embedded in a SiC/C/Si(3)N(4) matrix in greater than 90% yield up to 1000 degrees C. Variation of the pyrolysis temperature and time permitted control over the nucleation and growth of alpha-Fe particles, which ranged in size from around 15 to 700 A, and the crystallization of the surrounding matrix. The ceramics contained smaller alpha-Fe particles when prepared at temperatures lower than 900 degrees C and displayed superparamagnetic behavior, whereas the materials prepared at 1000 degrees C contained larger alpha-Fe particles and were ferromagnetic. This flexibility may be useful for particular materials applications. In addition, the composition of the ceramic was altered by changing the pyrolysis atmosphere to argon, which yielded ceramics that contain Fe(3)Si(5). The ceramics have been characterized by a combination of physical techniques, including powder X-ray diffraction, TEM, reflectance UV-vis/near-IR spectroscopy, elemental analysis, XPS, SQUID magnetometry, Mössbauer spectroscopy, nanoindentation, and SEM. Micromolding of the spirocyclic [1]ferrocenophane precursor within soft lithographically patterned channels housed inside silicon wafers followed by thermal ROP and pyrolysis enabled the formation of predetermined micron scale designs of the magnetic ceramic.

  13. Interactive effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin and retinoids on proliferation and differentiation in cultured human keratinocytes: quantification of cross-linked envelope formation

    International Nuclear Information System (INIS)

    Berkers, J.A.M.; Hassing, I.; Spenkelink, B.; Brouwer, A.; Blaauboer, B.J.

    1995-01-01

    Dioxins are potent inducers of chloracne in humans. This skin aberration can be interpreted as an altered differentiation pattern of acinar sebaceous base cells and a change in the rate of terminal differentiation of the keratinocytes. We measured this rate induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in primary cultures of human keratinocytes. As parameters for differentiation, we quantified the 35 S-methionine incorporation into cross-linked envelopes (revealing the total CLE biomass), as well as the number of microscopically visible CLEs. It was shown that TCDD is a very potent inducer of both CLE biomass and number with a half-maximal effect concentration (EC 50 ) of 1.4 nM. CLE biomass was maximally increased 10-fold and the number of cells in culture producing a CLE was increased from 15% in control cultures to maximally 75% of the cells in TCDD-treated cultures. Both effects were Ca 2+ -dependent and increased with elevated cell density, being optimal in post-confluent cultures. Retinoic acid dose-dependently decreased the effect of 10 -8 M TCDD, 10 -6 M having a nearly complete antagonistic action. This interaction of retinoic acid with TCDD-induced differentiation was non-competitive. Retinol was equally potent as an antagonist of the TCDD-induced elevation of CLE formation as compared with retinoic acid. Retinyl palmitate and etretinate were not very effective as TCDD antagonists. Supplementation of hydrocortisone suppressed the TCDD-induced keratinocyte differentiation. It was concluded that CLE biomass quantification provides a reliable and sensitive parameter for keratinocyte differentiation. In this in vitro system it is shown that TCDD strongly induces a switch from proliferation to terminal differentiation and that this effect can be antagonized effectively by retinoic acid and retinol. (orig.)

  14. Linking Plant Water-Use Efficiency and Depth of Water Uptake to Field­-Level Productivity Under Surplus and Deficit Irrigation in Almond Orchards

    Science.gov (United States)

    Seely, T.; Shackel, K.; Silva, L. C. R.

    2016-12-01

    The impact of water stress on depth of water uptake, as well as water­-use efficiency (WUE) at the tree-level and field-level was examined in almond orchards under varying degrees of deficit and surplus irrigation treatments. Three different orchards, spanning a latitudinal gradient (35° to 39° N) were sampled during two growing seasons in the central valley of CA. The orchards encompass a range of climatic and edaphic conditions, providing an opportunity for comparisons of WUE and orchard yield under contrasting environmental conditions. In each orchard, the control treatment received 100% replacement of water lost to evapotranspiration (ET), while the surplus treatment received 110% and the deficit treatment received 70% replenishment of ET, the latter simulating conditions of water stress. Preliminary results based on the analysis of carbon isotope ratios (δ13C) in leaves throughout the 2015 and 2016 growing seasons, reveal a significant change in WUE in all three orchard sites, increasing up to 20% on average in the deficit irrigation treatment relative to controls. In contrast, trees growing under surplus irrigation had the lowest WUE across all orchard sites. The difference in WUE between surplus irrigated trees and control irrigated trees within each orchard was not always statistically significant. These physiological responses to levels of water availability were not reflected in field-level orchard productivity, which was highly variable across orchard sites and treatments. Additionally, analysis of oxygen (δ18O) and hydrogen (δ2H) isotope ratios of stem, leaf, and soil water has been undertaken to determine the effect of water stress on the depth of root water uptake. The hypothesis that almond trees can effectively acclimate to water stress through higher WUE and deeper root water uptake compared to well-watered trees will be tested. This multi-scale, ecohydrological study will elucidate the impacts of drought on almond orchards, one of the most

  15. Study on formation process of layered MMEs based on field observation and petrographic characteristics: A case study from Taejongdae, Busan Korea.

    Science.gov (United States)

    Adam, M. S. A.; Kim, Y. S.; Kim, T.

    2016-12-01

    Mafic Magmatic Enclaves (MME) are a common feature in granitic rocks. However, the Multi-layered MME developed in the outcrop of Cretaceous granite in Taejongdae National Geopark, Busan is a unique phenomenon providing useful information on the formation of MMEs. Multi-layered MME is defined here as MME composed of several contrasting rock shells. Characteristics and origin of MMEs have been studied by several ways; descriptively, geochemically and isotopically due to their importance in the evolution of igneous rocks. This study focuses on the understanding of the formation mechanism of the multi-layers and their rock type diversity. To achieve these goals, field observation between the MMEs and the host granite, petrographic studies and XRF analysis have been carried out. The results show that the MMEs have different shapes and sizes, ranging from elliptical to angular, and from a few centimeters to a meter, respectively. Based on the lithology and the number of layers, the studied MMEs are subdivided into three types as followed; a) single layer type, b) double layer type, and c) triple layer type. The single and double layer types have relatively angular shapes, and their contacts with the host granite are commonly sharp. Layer-forming rocks are variable from mafic porphyritic, mafic fine- to medium- and felsic coarse-grained. The triple layer type has a circular to elliptical shape, while its contact with the host granite is gradual indicating diffusion. It also shows gradual compositional change from mafic to felsic. It is interesting that some of the triple MMEs are injected by granitic materials through cracks. That may indicate brittle deformation during cooling process. The two internal layers of the triple layer MMEs have almost the same mineral composition with different textures indicating the result of cooling process. However, the outer dioritic layer shows mixing composition of mafic and felsic magma, and thus it may indicate that it was generated

  16. Stomatal ozone fluxes over a barley field in Italy. "Effective exposure" as a possible link between exposure- and flux-based approaches

    Science.gov (United States)

    Gerosa, Giacomo; Marzuoli, Riccardo; Cieslik, Stanislaw; Ballarin-Denti, Antonio

    Fluxes of ozone as well as of sensible and latent heat were measured over a barley field in Northern Italy from April to June 2002 with the eddy-correlation technique in order to determine the dose of ozone taken up by plants during the whole grain filling and maturation period. Stomatal ozone fluxes were then calculated by using the similarity between gaseous exchange processes occurring inside the stomata involving ozone and water vapour, whose flux was available from the measurements. The dose was then obtained by integrating the stomatal flux over time. On the average, the stomatal flux was found to be approximately 50% of the total flux. This approach was compared to the currently used ozone risk assessment procedure based on the use of the exposure index AOT40, calculated from routine ozone concentration records. Important differences between these two approaches appeared. In order to assess ozone risk to vegetation in a realistic way, a new concept of "effective exposure", which combines both exposure and uptake approaches, is developed. A new risk assessment index is obtained by weighting exposure by a factor which includes stomatal conductance, obtained by a modelling procedure, which uses observational data available from routine monitoring stations. This new index, formally similar to AOT40, uses a lower ozone concentration threshold (evolution than the original AOT40 index. This approach permits to calculate ozone exposure taking physiological aspects into account, for situations where only ozone concentrations and meteorological observations are available, as direct flux data are difficult to obtain on a routine basis.

  17. Interfacial insertion of a poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) layer between the poly(3-hexyl thiophene) semiconductor and cross-linked poly(vinyl alcohol) insulator layer in organic field-effect transistors

    International Nuclear Information System (INIS)

    Cruz-Cruz, Isidro; Tavares, Ana C B; Hümmelgen, Ivo A; Reyes-Reyes, Marisol; López-Sandoval, Román

    2014-01-01

    The role of a thin layer of conductive poly(3,4-ethylenedioxythiophene) doped with polystyrene sulfonate (PEDOT : PSS), inserted between the gate dielectric and the active layer in poly(3-hexylthiophene)-based transistors was investigated. The devices were fabricated in the bottom-gate top-contact geometry by using cross-linked poly(vinyl alcohol) as the dielectric, whereas the PEDOT : PSS layer was prepared by using an aged aqueous dispersion with addition of different amounts of dimethyl sulfoxide (DMSO) as a secondary dopant. Under these conditions, both a significant reduction in the number of electrically active traps at the interface with the semiconductor and an improvement in the field-effect mobility were obtained, whereas the low power consumption was preserved. The threshold voltage was also displaced by approximately −1 V. (paper)

  18. SetLink the CERN Document Server Link Manager

    CERN Document Server

    Le Meur, Jean-Yves

    2000-01-01

    This paper analyses the problems encountered by electronic libraries to cope with long term keeping of on-line documents. What is thebest solution not to fill in a library system with non persistent addresses ? Different possible solutions are studied, based on theexperience of the CERN Document Server and its library. This paper will stress the importance of using a Link Manager for any long term Web server. It will explain how the CERN SetLink Link Manager is designed to handle a wide range of document types and formats, from photos in JPEG to eprints in PDF. It will also focus onother possibilities offered by using such an application, like automatic figures extraction or concatenation, full text searching andon-the-fly format conversions.

  19. X-ray induced formation of γ-H2AX foci after full-field digital mammography and digital breast-tomosynthesis.

    Directory of Open Access Journals (Sweden)

    Siegfried A Schwab

    Full Text Available PURPOSE: To determine in-vivo formation of x-ray induced γ-H2AX foci in systemic blood lymphocytes of patients undergoing full-field digital mammography (FFDM and to estimate foci after FFDM and digital breast-tomosynthesis (DBT using a biological phantom model. MATERIALS AND METHODS: The study complies with the Declaration of Helsinki and was performed following approval by the ethic committee of the University of Erlangen-Nuremberg. Written informed consent was obtained from every patient. For in-vivo tests, systemic blood lymphocytes were obtained from 20 patients before and after FFDM. In order to compare in-vivo post-exposure with pre-exposure foci levels, the Wilcoxon matched pairs test was used. For in-vitro experiments, isolated blood lymphocytes from healthy volunteers were irradiated at skin and glandular level of a porcine breast using FFDM and DBT. Cells were stained against the phosphorylated histone variant γ-H2AX, and foci representing distinct DNA damages were quantified. RESULTS: Median in-vivo foci level/cell was 0.086 (range 0.067-0.116 before and 0.094 (0.076-0.126 after FFDM (p = 0.0004. In the in-vitro model, the median x-ray induced foci level/cell after FFDM was 0.120 (range 0.086-0.140 at skin level and 0.035 (range 0.030-0.050 at glandular level. After DBT, the median x-ray induced foci level/cell was 0.061 (range 0.040-0.081 at skin level and 0.015 (range 0.006-0.020 at glandular level. CONCLUSION: In patients, mammography induces a slight but significant increase of γ-H2AX foci in systemic blood lymphocytes. The introduced biological phantom model is suitable for the estimation of x-ray induced DNA damages in breast tissue in different breast imaging techniques.

  20. Observations of the Hubble Deep Field with the Infrared Space Observatory .5. Spectral energy distributions, starburst models and star formation history

    DEFF Research Database (Denmark)

    Rowan Robinson, M.; Mann, R.G.; Oliver, S.J.

    1997-01-01

    the star formation rate can be deduced from the far-infrared luminosity, and derive star formation rates for these galaxies of 8-1000 phi M. yr(-1), where phi takes account of the uncertainty in the initial mass function, The HDF galaxies detected by ISO are clearly forming stars at, a prodigious rate...... compared with nearby normal galaxies, We discuss the implications of our detections for the history of star and heavy element formation in the Universe, Although uncertainties in the calibration, reliability of source detection, associations and starburst models remain, it is clear that dust plays...

  1. Sex-linked dominant

    Science.gov (United States)

    Inheritance - sex-linked dominant; Genetics - sex-linked dominant; X-linked dominant; Y-linked dominant ... can be either an autosomal chromosome or a sex chromosome. It also depends on whether the trait ...

  2. Ferrofluid spiral formations and continuous-to-discrete phase transitions under simultaneously applied DC axial and AC in-plane rotating magnetic fields

    International Nuclear Information System (INIS)

    Rhodes, Scott; Perez, Juan; Elborai, Shihab; Lee, Se-Hee; Zahn, Markus

    2005-01-01

    New flows and instabilities are presented for a ferrofluid drop contained in glass Hele-Shaw cells with simultaneously applied in-plane clockwise rotating and DC axial uniform magnetic fields. When a ferrofluid drop is stressed by a uniform DC axial magnetic field, up to ∼250 G in 0.9-1.4 mm gap Hele-Shaw cells, the drop forms a labyrinth pattern. With subsequent application of an in-plane uniform rotating magnetic field, up to ∼100 G rms at frequency 20-40 Hz, smooth spirals form from viscous shear due to ferrofluid flow. If the rotating magnetic field is applied first, the drop is held together without a labyrinth. Gradual increase of the DC axial magnetic field, to a critical magnetic field value, results in an abrupt phase transformation from a large drop to many small discrete droplets. A preliminary minimum magnetization and surface energy analysis is presented to model the phase transformation

  3. Modeling the kinetics of hydrates formation using phase field method under similar conditions of petroleum pipelines; Modelagem da cinetica de formacao de hidratos utilizando o Modelo do Campo de Fase em condicoes similares a dutos de petroleo

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Mabelle Biancardi; Castro, Jose Adilson de; Silva, Alexandre Jose da [Universidade Federal Fluminense (UFF), Volta Redonda, RJ (Brazil). Programa de Pos-Graduacao em Engenharia Metalurgica], e-mails: mabelle@metal.eeimvr.uff.br; adilson@metal.eeimvr.uff.br; ajs@metal.eeimvr.uff.br

    2008-10-15

    Natural hydrates are crystalline compounds that are ice-like formed under oil extraction transportation and processing. This paper deals with the kinetics of hydrate formation by using the phase field approach coupled with the transport equation of energy. The kinetic parameters of the hydrate formation were obtained by adjusting the proposed model to experimental results in similar conditions of oil extraction. The effect of thermal and nucleation conditions were investigated while the rate of formation and morphology were obtained by numerical computation. Model results of kinetics growth and morphology presented good agreement with the experimental ones. Simulation results indicated that super-cooling and pressure were decisive parameters for hydrates growth, morphology and interface thickness. (author)

  4. Fields Medallists

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 4; Issue 11. Fields Medallists - Curtis T. McMullen. Nimish A Shah. Research News Volume 4 Issue 11 November 1999 pp 80-83. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/004/11/0080-0083 ...

  5. Anthropogenic soil formation and agricultural history of the open fields of Valthe (Drenthe, the Netherlands) in mediaeval and early modern times

    NARCIS (Netherlands)

    Smeerdijk, van D.G.; Spek, T.; Kooistra, M.J.

    1995-01-01

    An interdisciplinary study on anthropogenic arable soils in the Dutch Province of Drenthe resulted in valuable information on reclamation history, soil formation and arable farming in the Middle Ages and Early Modern Times. This paper describes a genetic typology of Drenthe plaggen soils, based on

  6. Fossilized iron bacteria reveal a pathway to the biological origin of banded iron formation.

    Science.gov (United States)

    Chi Fru, Ernest; Ivarsson, Magnus; Kilias, Stephanos P; Bengtson, Stefan; Belivanova, Veneta; Marone, Federica; Fortin, Danielle; Broman, Curt; Stampanoni, Marco

    2013-01-01

    Debates on the formation of banded iron formations in ancient ferruginous oceans are dominated by a dichotomy between abiotic and biotic iron cycling. This is fuelled by difficulties in unravelling the exact processes involved in their formation. Here we provide fossil environmental evidence for anoxygenic photoferrotrophic deposition of analogue banded iron rocks in shallow marine waters associated with an Early Quaternary hydrothermal vent field on Milos Island, Greece. Trace metal, major and rare earth elemental compositions suggest that the deposited rocks closely resemble banded iron formations of Precambrian origin. Well-preserved microbial fossils in combination with chemical data imply that band formation was linked to periodic massive encrustation of anoxygenic phototrophic biofilms by iron oxyhydroxide alternating with abiotic silica precipitation. The data implicate cyclic anoxygenic photoferrotrophy and their fossilization mechanisms in the construction of microskeletal fabrics that result in the formation of characteristic banded iron formation bands of varying silica and iron oxide ratios.

  7. Metal Catalysis with Nanostructured Metals Supported Inside Strongly Acidic Cross-linked Polymer Frameworks: Influence of Reduction Conditions of AuIII-containing Resins on Metal Nanoclusters Formation in Macroreticular and Gel-Type Materials

    Czech Academy of Sciences Publication Activity Database

    Calore, L.; Cavinato, g.; Canton, P.; Peruzzo, L.; Banavali, R.; Jeřábek, Karel; Corain, B.

    2012-01-01

    Roč. 391, AUG 30 (2012), s. 114-120 ISSN 0020-1693 Institutional support: RVO:67985858 Keywords : strongly acidic cross-linked polymer * frameworks * gold(0) nanoclusters Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 1.687, year: 2012

  8. The CCSDS Next Generation Space Data Link Protocol (NGSLP)

    Science.gov (United States)

    Kazz, Greg J.; Greenberg, Edward

    2014-01-01

    next leap in performance for space link communications. Field Programmable Gate Arrays (FPGAs) provide the capability to incorporate high performance forward error correcting codes implemented within software transponders providing improved performance in data transfer, ranging, link security, and time correlation. Given these synergistic technological breakthroughs, the time has come to take advantage of them in applying them to both on going (e.g., command, telemetry) and emerging (e.g., space link security, optical communication) space link applications. However one of the constraining factors within the Data Link Layer in realizing these performance gains is the lack of a generic transfer frame format and common supporting services amongst the existing CCSDS link layer protocols. Currently each of the four CCSDS link layer protocols (TM, TC, AOS, and Proximity-1) have unique formats and services which prohibits their reuse across the totality of all space link applications of CCSDS member space agencies. For example, Mars missions. These missions implement their proximity data link layer using the Proximity-1 frame format and the services it supports but is still required to support the direct from Earth (TC) protocols and the Direct To Earth (AOS/TM) protocols. The prime purpose of this paper, is to describe a new general purpose CCSDS Data Link layer protocol, the NGSLP that will provide the required services along with a common transfer frame format for all the CCSDS space links (ground to/from space and space to space links) targeted for emerging missions after a CCSDS agency-wide coordinated date. This paper will also describe related options that can be included for the Coding and Synchronization sub-layer of the Data Link layer to extend the capacities of the link and additionally provide an independence of the transfer frame sub-layer from the coding sublayer. This feature will provide missions the option of running either the currently performed

  9. Linking numbers and variational method

    International Nuclear Information System (INIS)

    Oda, I.; Yahikozawa, S.

    1989-09-01

    The ordinary and generalized linking numbers for two surfaces of dimension p and n-p-1 in an n dimensional manifold are derived. We use a variational method based on the properties of topological quantum field theory in order to derive them. (author). 13 refs, 2 figs

  10. Effects of soil macrofauna on other soil biota and soil formation in reclaimed and unreclaimed post mining sites: Results of a field microcosm experiment

    Czech Academy of Sciences Publication Activity Database

    Frouz, Jan; Elhottová, Dana; Kuráž, V.; Šourková, Monika

    2006-01-01

    Roč. 33, č. 3, (2006), s. 308-320 ISSN 0929-1393 R&D Projects: GA ČR(CZ) GA526/01/1055; GA ČR(CZ) GA526/03/1259; GA AV ČR(CZ) 1QS600660505 Institutional research plan: CEZ:AV0Z6066911 Keywords : fauna * soil formation * microbial community Subject RIV: EH - Ecology, Behaviour Impact factor: 1.929, year: 2006

  11. Origin and evolution of formation water at the Jujo-Tecominoacan oil reservoir, Gulf of Mexico. Part 2: Isotopic and field-production evidence for fluid connectivity

    Energy Technology Data Exchange (ETDEWEB)

    Birkle, Peter, E-mail: birkle@iie.org.mx [Instituto de Investigaciones Electricas (IIE), Gerencia de Geotermia, Cuernavaca 62490, Morelos (Mexico); Garcia, Bernardo Martinez; Milland Padron, Carlos M. [PEMEX Exploracion y Produccion, Region Sur, Activo Integral Bellota-Jujo, Diseno de Explotacion, Cardenas, Tabasco (Mexico); Eglington, Bruce M. [Saskatchewan Isotope Laboratory, University of Saskatchewan, Saskatoon, Canada SK S7N 5E2 (Canada)

    2009-04-15

    The chemical and isotopic characterization of formation water from 18 oil production wells, extracted from 5200 to 6100 m b.s.l. at the Jujo-Tecominoacan carbonate reservoir in SE-Mexico, and interpretations of historical production records, were undertaken to determine the origin and hydraulic behavior of deep groundwater systems. The infiltration of surface water during Late Pleistocene to Early Holocene time is suggested by {sup 14}C-concentrations from 2.15 to 31.86 pmC, and by {sup 87}Sr/{sup 86}Sr-ratios for high-salinity formation water (0.70923-0.70927) that are close to the composition of Holocene to modern seawater. Prior to infiltration, the super-evaporation of seawater reached maximum TDS concentrations of 385 g/L, with lowest {delta}{sup 18}O values characterizing the most hypersaline samples. Minor deviations of formation water and dolomite host rocks from modern and Jurassic {sup 87}Sr/{sup 86}Sr-seawater composition, respectively, suggest ongoing water-rock interaction, and partial isotopic equilibration between both phases. The abundance of {sup 14}C in all sampled formation water, {sup 87}Sr/{sup 86}Sr-ratios for high-salinity water close to Holocene - present seawater composition, a water salinity distribution that is independent of historic water-cut, and a total water extraction volume of 2.037 MMm{sup 3} (1/83-4/07) excludes a connate, oil-leg origin for the produced water of the Jurassic-Cretaceous mudstone-dolomite sequence. Temporal fluctuations of water chemistry in production intervals, the accelerated migration of water fronts from the reservoir flanks, and isotopic mixing trends between sampled wells confirms the existence of free aquifer water below oil horizons. Vertical and lateral hydraulic mobility has probably been accelerated by petroleum extraction. The combination of interpreting historical fluctuations of salinity and water percentage in production wells with chemical-isotopic analysis of formation water resulted in a

  12. Origin and evolution of formation water at the Jujo-Tecominoacan oil reservoir, Gulf of Mexico. Part 2: Isotopic and field-production evidence for fluid connectivity

    International Nuclear Information System (INIS)

    Birkle, Peter; Garcia, Bernardo Martinez; Milland Padron, Carlos M.; Eglington, Bruce M.

    2009-01-01

    The chemical and isotopic characterization of formation water from 18 oil production wells, extracted from 5200 to 6100 m b.s.l. at the Jujo-Tecominoacan carbonate reservoir in SE-Mexico, and interpretations of historical production records, were undertaken to determine the origin and hydraulic behavior of deep groundwater systems. The infiltration of surface water during Late Pleistocene to Early Holocene time is suggested by 14 C-concentrations from 2.15 to 31.86 pmC, and by 87 Sr/ 86 Sr-ratios for high-salinity formation water (0.70923-0.70927) that are close to the composition of Holocene to modern seawater. Prior to infiltration, the super-evaporation of seawater reached maximum TDS concentrations of 385 g/L, with lowest δ 18 O values characterizing the most hypersaline samples. Minor deviations of formation water and dolomite host rocks from modern and Jurassic 87 Sr/ 86 Sr-seawater composition, respectively, suggest ongoing water-rock interaction, and partial isotopic equilibration between both phases. The abundance of 14 C in all sampled formation water, 87 Sr/ 86 Sr-ratios for high-salinity water close to Holocene - present seawater composition, a water salinity distribution that is independent of historic water-cut, and a total water extraction volume of 2.037 MMm 3 (1/83-4/07) excludes a connate, oil-leg origin for the produced water of the Jurassic-Cretaceous mudstone-dolomite sequence. Temporal fluctuations of water chemistry in production intervals, the accelerated migration of water fronts from the reservoir flanks, and isotopic mixing trends between sampled wells confirms the existence of free aquifer water below oil horizons. Vertical and lateral hydraulic mobility has probably been accelerated by petroleum extraction. The combination of interpreting historical fluctuations of salinity and water percentage in production wells with chemical-isotopic analysis of formation water resulted in a successful method to distinguish four groundwater bodies

  13. Development of a geothermal resource in a fractured volcanic formation: Case study of the Sumikawa Geothermal Field, Japan. Final report, May 1, 1995--November 30, 1997

    Energy Technology Data Exchange (ETDEWEB)

    Garg, S.K.; Combs, J.; Pritchett, J.W. [and others

    1997-07-01

    The principal purpose of this case study of the Sumikawa Geothermal Field is to document and to evaluate the use of drilling logs, surface and downhole geophysical measurements, chemical analyses and pressure transient data for the assessment of a high temperature volcanic geothermal field. This comprehensive report describes the work accomplished during FY 1993-1996. A brief review of the geological and geophysical surveys at the Sumikawa Geothermal Field is presented (Section 2). Chemical data, consisting of analyses of steam and water from Sumikawa wells, are described and interpreted to indicate compositions and temperatures of reservoir fluids (Section 3). The drilling information and downhole pressure, temperature and spinner surveys are used to determine feedzone locations, pressures and temperatures (Section 4). Available injection and production data from both slim holes and large-diameter wells are analyzed to evaluate injectivity/productivity indices and to investigate the variation of discharge rate with borehole diameter (Section 5). New interpretations of pressure transient data from several wells are discussed (Section 6). The available data have been synthesized to formulate a conceptual model for the Sumikawa Geothermal Field (Section 7).

  14. Late Devonian (Frasnian) bivalves from the Nocedo Formation: the results of Wilhelm Kegel’s 1927 field trip to northern Spain

    NARCIS (Netherlands)

    Amler, M.R.W.

    2010-01-01

    During a field trip to the Peña-Corada Unit of the southernmost Esla region of the Cantabrian Mountains in 1927, the German stratigrapher Wilhelm Kegel sampled brachiopods and bivalves from a section in the Laoz valley near La Ercina. The stratigraphic position is believed to be part of the Nocedo

  15. Observations of the Hubble Deep Field with the Infrared Space Observatory .5. Spectral energy distributions, starburst models and star formation history

    DEFF Research Database (Denmark)

    Rowan Robinson, M.; Mann, R.G.; Oliver, S.J.

    1997-01-01

    We have modelled the spectral energy distributions of the 13 Hubble Deep Field (HDF) galaxies reliably detected by the Infrared Space Observatory (ISO). For two galaxies the emission detected by ISO is consistent with being starlight or the infrared 'cirrus' in the galaxies. For the remaining II...

  16. Cosmic Rays and Clouds, 1. Formation of Lead Mesoatoms In Neutron Monitor By Soft Negative Muons and Expected Atmospheric Electric Field Effect In The Cosmic Ray Neutron Component

    Science.gov (United States)

    Dorman, L. I.; Dorman, I. V.

    We extend our model (Dorman and Dorman, 1995) of cosmic ray atmospheric electric field effect on the case of neutron monitor. We take into account that about 0.07 of neu- tron monitor counting rate caused by negative soft muons captured by lead nucleons and formed mesoatoms with generation of several MeV energy neutrons from lead. In this case the neutron monitor or neutron supermonitor works as analyzer which de- tects muons of only one, negative sign. It is very important because the atmospheric electric field effect have opposite signs for positive and negative muons that main part of this effect in the muon telescope or in ionization chamber is compensated and we can observe only small part of total effect of one sign muons. On the basis of our gen- eral theory of cosmic ray meteorological effects with taking into account of negative soft muon acceleration and deceleration in the Earth atmosphere (in dependence of di- rection and intensity of electric field) we discuss the possibility of existing this effect in cosmic ray neutron component and made some rough estimations. REFERENCES: Dorman L.I. and Dorman I.V., 1995. "Cosmic-ray atmospheric electric field effects". Canadian J. of Physics, Vol. 73, pp. 440-443.

  17. Effect of 2-propenyltrimethylsilane and magnetic field effect on photochemical Fe/Co fine particle formation from a ternary gaseous mixture

    Czech Academy of Sciences Publication Activity Database

    Morita, H.; Hattori, K.; Šubrt, Jan

    2011-01-01

    Roč. 218, č. 1 (2011), s. 111-116 ISSN 1010-6030 Institutional research plan: CEZ:AV0Z40320502 Keywords : gas phase photochemical reaction * aerosol particle * magnetic field effect * iron pentacarbonyl * cobalt tricarbonyl nitrosyl Subject RIV: CA - Inorganic Chemistry Impact factor: 2.421, year: 2011

  18. Magnetic fields

    International Nuclear Information System (INIS)

    Mestel, L.; Arizona Univ., Tucson)

    1985-01-01

    The role of the Galactic magnetic field in the early stages of star formation is examined. The dynamical and observational consequences of the anisotropic collapse of cool gas clouds permeated by the local Galactic magnetic field are discussed. Magneto-gravitational equilibria of such clouds with subcritical mass-flux ratios, especially in the thin disk approximation, are addressed. Magnetic braking of both subcritical and supercritical masses is considered, and the consequences of flux leakage during the molecular cloud phase are discussed, including the effect on field topology

  19. Field Observation of Heterogeneous Formation of Dicarboxylic acids, Keto-carboxylic acids, α-Dicarbonyls and Nitrate in Xi'an, China during Asian dust storm periods

    Science.gov (United States)

    Wang, G.; Wang, J.; Ren, Y.; Li, J.

    2015-12-01

    To understand the formation mechanism of secondary organic aerosols (SOA) on dust surfaces, this study investigated the concentrations and compositions of dicarboxylic acids (C2-C11), keto-carboxylic acids (C3-C7), α-dicarbonyls and inorganic ions in size-segregated aerosols (9-stages) collected in Xi'an, China during the nondust storm and dust storm periods of 2009 and 2011. During the events the ambient particulate dicarboxylic acids were 932-2240 ng m-3, which are comparable and even higher than those in nondust periods. Molecular compositions of the above SOA are similar to those in nondust periods with oxalic acid being the leading species. In the presence of the dust storms, all the above mentioned SOA species in Xi'an were predominantly enriched on the coarse particles (>2.1μm), and oxalic acid well correlated with NO3- (R2=0.72, pfine particles and a strong correlation of oxalic acid with SO42-. Our results further demonstrate that NO3- in the dust periods in Xi'an was mostly derived from secondary oxidation, whereas SO42- during the events was largely derived from surface soil of Gobi deserts. We propose a formation pathway to explain these observations, in which nitric acid and/or nitrogen oxides react with dust to produce Ca(NO3)2 and form a liquid phase on the surface of dust aerosols via water vapor-absorption of Ca(NO3)2, followed by a partitioning of the gas-phase water-soluble organic precursors (e.g.,glyoxal and methylglyoxal) into the aqueous-phase and a subsequent oxidation into oxalic acid. To the best of our knowledge, we found for the first time the enrichment of glyoxal and methylglyoxal on dust surface. Our data suggest an important role of nitrate in the heterogeneous formation process of SOA on the surface of Asian dust.

  20. Field observation on secondary organic aerosols during Asian dust storm periods: Formation mechanism of oxalic acid and related compounds on dust surface

    Science.gov (United States)

    Wang, Gehui; Cheng, Chunlei; Meng, Jingjing; Huang, Yao; Li, Jianjun; Ren, Yanqin

    2015-07-01

    Chemical evolution of East Asian dust during transpacific transport has been given much attention for inorganic species such as sulfate, nitrate and ammonium. However, the role of organic species during the transport has almost entirely been ignored. To understand the formation mechanism of secondary organic aerosols (SOA) on dust surfaces, this study investigated the concentrations and compositions of dicarboxylic acids, keto-carboxylic acids, α-dicarbonyls and inorganic ions in size-segregated aerosols (9-stages) collected in Xi'an, central China during the two dust storm episodes in the springs of 2009 and 2011 and compared with those in nondust storm periods. During the events the ambient particulate dicarboxylic acids were 932-2240 ng m-3, which are comparable and even higher than those in nondust periods. Molecular compositions of the above SOA are similar to those in nondust periods with oxalic acid being the leading species. In the presence of the dust storms, all the above mentioned SOA species in Xi'an were predominantly enriched on the coarse particles (>2.1 μm), and oxalic acid well correlated with NO3- (R2 = 0.72, p fine mode and a strong correlation of oxalic acid with SO42-. We propose a formation pathway to explain these observations, in which nitric acid and/or nitrogen oxides react with dust to produce Ca(NO3)2 and form a liquid phase on the surface of dust aerosols via water vapor-absorption of Ca(NO3)2, followed by a partitioning of the gas-phase water-soluble organic precursors (e.g.,glyoxal and methylglyoxal) into the aqueous-phase and a subsequent oxidation into oxalic acid. To the best of our knowledge, we found for the first time the enrichment of glyoxal and methylglyoxal on dust surface. Our data suggest an important role of nitrate in the heterogeneous formation process of SOA on the surface of dust.

  1. Linked Metadata - lightweight semantics for data integration (Invited)

    Science.gov (United States)

    Hendler, J. A.

    2013-12-01

    The "Linked Open Data" cloud (http://linkeddata.org) is currently used to show how the linking of datasets, supported by SPARQL endpoints, is creating a growing set of linked data assets. This linked data space has been growing rapidly, and the last version collected is estimated to have had over 35 billion 'triples.' As impressive as this may sound, there is an inherent flaw in the way the linked data story is conceived. The idea is that all of the data is represented in a linked format (generally RDF) and applications will essentially query this cloud and provide mashup capabilities between the various kinds of data that are found. The view of linking in the cloud is fairly simple -links are provided by either shared URIs or by URIs that are asserted to be owl:sameAs. This view of the linking, which primarily focuses on shared objects and subjects in RDF's subject-predicate-object representation, misses a critical aspect of Semantic Web technology. Given triples such as * A:person1 foaf:knows A:person2 * B:person3 foaf:knows B:person4 * C:person5 foaf:name 'John Doe' this view would not consider them linked (barring other assertions) even though they share a common vocabulary. In fact, we get significant clues that there are commonalities in these data items from the shared namespaces and predicates, even if the traditional 'graph' view of RDF doesn't appear to join on these. Thus, it is the linking of the data descriptions, whether as metadata or other vocabularies, that provides the linking in these cases. This observation is crucial to scientific data integration where the size of the datasets, or even the individual relationships within them, can be quite large. (Note that this is not restricted to scientific data - search engines, social networks, and massive multiuser games also create huge amounts of data.) To convert all the triples into RDF and provide individual links is often unnecessary, and is both time and space intensive. Those looking to do on the

  2. Final Report for Project DE-SC0006958: "An Investigation of the Effects of magnetic Fields and Collisionality on Shock Formation in Radiatively Cooled Plasma Flows"

    Energy Technology Data Exchange (ETDEWEB)

    Bott-Suzuki, Simon

    2014-11-05

    We have developed a new experimental platform to study bow-shock formation in plasma flows generated using an inverse wire array z-pinch. We have made significant progress on the analysis of both hydrodynamic and magnetized shocks using this system. The hydrodynamic experiments show formation of a well-defined Mach cone, and highly localized shock strong associated with radiative losses and rapidly cooling over the shock. Magnetized shocks show that the balance of magnetic and ram pressures dominate the evolution of the shock region, generating a low plasma beta void around the target. Manuscripts are in preparation for publication on both these topics. We have also published the development of a novel diagnostic method which allow recovery of interferometry and self-emission data along the same line of sight. Finally, we have carried out work to integrate a kinetic routine with the 3D MHD code Gorgon, however it remains to complete this process. Both undergraduate and graduate students have been involved in both the experimental work and publications.

  3. Stellar formation

    CERN Document Server

    Reddish, V C

    1978-01-01

    Stellar Formation brings together knowledge about the formation of stars. In seeking to determine the conditions necessary for star formation, this book examines questions such as how, where, and why stars form, and at what rate and with what properties. This text also considers whether the formation of a star is an accident or an integral part of the physical properties of matter. This book consists of 13 chapters divided into two sections and begins with an overview of theories that explain star formation as well as the state of knowledge of star formation in comparison to stellar structure

  4. Strategies for the formation of human resources in the mexican nuclear field; Estrategias para la formacion de recursos humanos en el campo nuclear mexicano

    Energy Technology Data Exchange (ETDEWEB)

    Gomez T, A.M. [ININ, Carretera Mexico-Toluca s/n, 52750 La Marquesa, Ocoyoacac, Estado de Mexico (Mexico); Valle G, E. del [ESFM, IPN, Unidad Profesional ' Adolfo LopezMateos' , Av. Politecnico Nacional, 07738 Mexico D.F. (Mexico); Francois L, J.L. [Facultad de Ingenieria, UNAM, Paseo Cuauhnahuac 8532, Jiutepec, 62550 Morelos (Mexico); Espinosa P, G. [Universidad Autonoma Metropolitana Iztapalapa, Av. San Rafael Atlixco 186 Col. Vicentina, 09340 Mexico D.F. (Mexico); Mireles G, F. [Universidad Autonoma de Zacatecas, CREN, Av. Ramon Lopez Velarde 801, 98000 Zacatecas (Mexico); Croche B, R. [Universidad Veracruzana, FIME-Xalapa Lomas de Estadio s/n, Xalapa, 91090 Veracruz (Mexico); Lartigue G, J. [Facultad de Quimica-D-UNAM Ciudad Universitaria, 04510 Mexico D.F. (Mexico)]. e-mail: amgt@nuclear.inin.mx

    2007-07-01

    This work looks for to put in the discussion table the topic of the formation of human resources highly qualified that doubtless will need the country in the short term, same that will have to begin to be formed from now on to be able to satisfy the demand in the next future. They take like base several studies carried out by the NEA/OECD and the recommendations that have emanated of the same ones for later to make an approach of the current Mexican situation and to conclude with a series of recommendations that have been identified. The recommendations here exposed, they are only the thought of the authors and in no way they are based on an already carried out study. However it will be important to open the debate on the real strategies to have a national nuclear politics based on solid resultant foundations of the production and training of brilliant human resources. (Author)

  5. Bone formation in axial spondyloarthritis.

    Science.gov (United States)

    Lories, Rik J; Haroon, Nigil

    2014-10-01

    The success of targeted therapies directed against tumor necrosis factor for patients with spondyloarthritis has shifted the focus of physicians and scientists towards the prevention of structural damage to the involved structures, in particular the sacroiliac joints and the spine, to avoid loss of function and disability. Structural damage to the skeleton as witnessed by radiography mainly consists of new bone formation potentially progressively leading to spine or joint ankylosis. This important long-term outcome parameter has been difficult to study, not alone because the time window for change may be long but also because human tissues with direct translational relevance are rarely available. Data from rodent models have identified growth factor signaling pathways as relevant targets. Both human and animal studies have tried to understand the link between inflammation and new bone formation. At the current moment, most evidence points towards a strong link between both but with the question still lingering about the sequence of events, disease triggers, and the interdependence of both features of disease. New discoveries such as a masterswitch T cell population that carries the IL23 receptor and the analysis of auto-antibodies directed again noggin and sclerostin are contributing to innovative insights into the pathophysiology of disease. Long-term data with tumor necrosis factor (TNF) inhibitors also suggest that some window of opportunity may exist to inhibit structural disease progression. All these data provide support for a further critical analysis of the available datasets and boost research in the field. The introduction of novel disease definitions, in particular the characterization of non-radiographic axial spondyloarthritis patients, will likely be instrumental in our further understanding of structural damage. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Linked data management

    CERN Document Server

    Hose, Katja; Schenkel, Ralf

    2014-01-01

    Linked Data Management presents techniques for querying and managing Linked Data that is available on today’s Web. The book shows how the abundance of Linked Data can serve as fertile ground for research and commercial applications. The text focuses on aspects of managing large-scale collections of Linked Data. It offers a detailed introduction to Linked Data and related standards, including the main principles distinguishing Linked Data from standard database technology. Chapters also describe how to generate links between datasets and explain the overall architecture of data integration systems based on Linked Data. A large part of the text is devoted to query processing in different setups. After presenting methods to publish relational data as Linked Data and efficient centralized processing, the book explores lookup-based, distributed, and parallel solutions. It then addresses advanced topics, such as reasoning, and discusses work related to read-write Linked Data for system interoperation. Desp...

  7. The cross linking of EPDM and NBR rubber

    Directory of Open Access Journals (Sweden)

    Samardžija-Jovanović Suzana

    2005-01-01

    Full Text Available In the process of macromolecule cross linking, the choice of type and quantity of the components and the experimental conditions are important to obtain the new cross linked materials with better mechanical and chemical characteristics. The cross linking method depends on the rubber type and structure. Intermolecular cross linking results in the formation elastomer network. The basis of the cross linking process, between ethylene propylene diene rubber (EPDM and acrylonitrile butadiene rubber (NBR, is a chemical reaction. Fillers and other additives are present in different mass ratios in the material. The exploitation properties of the cross linked materials depend on the quantity of additive in the cross linked systems.

  8. TWSTFT Link Calibration Report

    Science.gov (United States)

    2015-09-01

    traveling calibration station (calibrator) consisting of N (≥2) GNSS receivers+antennas+cables and PPS/frequency-distributors. It is a pre-cabled black...the PTB is taken as the reference of the calibration, a GNSS time link correction is equal to the classic GNSS equipment calibration correction [8...TWSTFT link calibration. If we replace the TWSTFT link by a GNSS link or a optical fiber (OF), it becomes a GNSS or an OF time link calibration. This

  9. Enhancing Micro-Cathode Arc Thruster (muCAT) Plasma Generation to Analyze Magnetic Field Angle Effects on Sheath Formation in Hall Thrusters

    Science.gov (United States)

    Lukas, Joseph Nicholas

    Using a Delta IV or Atlas V launch vehicle to send a payload into Low Earth Orbit can cost between 13,000 and 14,000 per kilogram. With payloads that utilize a propulsion system, maximizing the efficiency of that propulsion system would not only be financially beneficial, but could also increase the range of possible missions and allow for a longer mission lifetime. This dissertation looks into efficiency increases in the Micro-Cathode Arc Thruster (muCAT) and Hall Thruster. The muCAT is an electric propulsion device that ablates solid cathode material, through an electrical arc discharge, to create plasma and ultimately produce thrust. About 90% of the arc discharge current is conducted by electrons, which go toward heating the anode and contribute very little to thrust, with only the remaining 10% going toward thrust in the form of ion current. I will discuss the results of an experiment in which electron heating on a low melting point anode was shown to increase ion current, which theoretically should increase thrust levels at low frequencies. Another feature of the muCAT is the use of an external magnetic solenoid which increases thrust, ion current, and causes uniform cathode erosion. An experiment has shown that efficiency can also be increased by removing the external magnetic field power supply and, instead, utilizing the residual arc current to power the magnetic solenoid. A Hall Thruster is a type of electric propulsion device that accelerates ions across an electric potential between an anode and magnetically trapped electrons. The limiting factor in Hall Thruster operation is the lifetime of the wall material. During operation, a positively charged layer forms over the surface of the walls, known as a plasma sheath, which contributes to wall erosion. Therefore, by reducing or eliminating the sheath layer, Hall Thruster operational lifetime can increase. Computational modeling has shown that large magnetic field angles and large perpendicular electric

  10. Project and analysis of the toroidal magnetic field production circuits and the plasma formation of the ETE (Spherical Tokamak Experiment) tokamak

    International Nuclear Information System (INIS)

    Barbosa, Luis Filipe F.P.W.; Bosco, Edson del.

    1994-01-01

    This report presents the project and analysis of the circuit for production of the toroidal magnetic field in the Tokamak ETE (Spherical Tokamak Experiment). The ETE is a Tokamak with a small-aspect-ratio parameter to be used for studying the plasma physics for the research on thermonuclear fusion. This machine is being constructed at the Laboratorio Associado de Plasma (LAP) of the Instituto Nacional de Pesquisas Espaciais (INPE) in Sao Jose dos Campos, SP, Brazil. (author). 20 refs., 39 figs., 4 tabs

  11. Modelling of Continental Lithosphere Breakup and Rifted Margin Formation in Response to an Upwelling Divergent Flow Field Incorporating a Temperature Dependent Rheology

    Science.gov (United States)

    Tymms, V. J.; Kusznir, N. J.

    2005-05-01

    We numerically model continental lithosphere deformation leading to breakup and sea floor spreading initiation in response to an imposed upwelling and divergent flow field applied to continental lithosphere and asthenosphere. The model is used to predict rifted continental margin lithosphere thinning and temperature structure. Model predictions are compared with observed rifted margin structure for four diverse case studies. Prior to application of the upwelling divergent flow field the continental lithosphere is undeformed with a uniform temperature gradient. The upwelling divergent flow field is defined kinematically using boundary conditions consisting of the upwelling velocity Vz at the divergence axis and the half divergence rate Vx . The resultant velocity field throughout the continuum is computed using finite element (FE) code incorporating a Newtonian temperature dependent rheology. The flow field is used to advect the continental lithosphere material and lithospheric and asthenospheric temperatures. Viscosity structure is hence modified and the velocities change correspondingly in a feedback loop. We find the kinematic boundary conditions Vz and Vx to be of first order importance. A high Vz/Vx (greater than10), corresponding to buoyancy assisted flow, leads to minimal mantle exhumation and a well defined continent ocean transition consistent with observations at volcanic margins. For Vz/Vx near unity, corresponding to plate boundary driven divergence, mantle exhumation over widths of up to 100 km is predicted which is consistent with observations at non-volcanic margins. The FE method allows the upwelling velocity Vz to be propagated upwards from the top of the asthenosphere to the Earth's surface without the requirement of imposing Vx. When continental breakup is achieved the half divergence velocity Vx can be applied at the lithosphere surface and the upwelling velocity Vz left free. We find this time and space dependent set of boundary conditions is

  12. Modeling the formation and aging of secondary organic aerosols in the Los Angeles metropolitan region during the CalNex 2010 field campaign

    Science.gov (United States)

    Hayes, P. L.; Ma, P. K.; Jimenez, J. L.; Zhao, Y.; Robinson, A. L.; Carlton, A. M. G.; Baker, K. R.; Ahmadov, R.; Washenfelder, R. A.; Alvarez, S. L.; Rappenglück, B.; Gilman, J.; Kuster, W.; De Gouw, J. A.; Prevot, A. S.; Zotter, P.; Szidat, S.; Kleindienst, T. E.; Offenberg, J. H.

    2015-12-01

    Several different literature parameterizations for the formation and evolution of urban secondary organic aerosol (SOA) are evaluated using a box model representing the Los Angeles Region during CalNex. The model SOA formed only from the oxidation of VOCs (V-SOA) is insufficient to explain the observed SOA concentrations, even when using SOA parameterizations with multi-generation oxidation that produce much higher yields than have been observed in chamber experiments, or when increasing yields to their upper limit estimates accounting for recently reported losses of vapors to chamber walls. Including SOA from primary semi-volatile and intermediate volatility organic compounds (P-S/IVOCs) following the parameterizations of Robinson et al. (2007), Grieshop et al. (2009), or Pye and Seinfeld (2010) improves model/measurement agreement for mass concentration at shorter photochemical ages (0.5 days). Our results strongly suggest that other precursors besides VOCs are needed to explain the observed SOA concentrations. In contrast, all of the literature P-S/IVOC parameterizations over-predict urban SOA formation at long photochemical ages (3 days) compared to observations from multiple sites, which can lead to problems in regional and global modeling. Sensitivity studies that reduce the IVOC emissions by one-half in the model improve SOA predictions at these long ages. In addition, when IVOC emissions in the Robinson et al. parameterization are constrained using recently reported measurements of these species model/measurement agreement is achieved. The amounts of SOA mass from diesel vehicles, gasoline vehicles, and cooking emissions are estimated to be 16 - 27%, 35 - 61%, and 19 - 35%, respectively, depending on the parameterization used, which is consistent with the observed fossil fraction of urban SOA, 71(±3)%. The percentage of SOA from diesel vehicle emissions is the same, within the estimated uncertainty, as reported in previous work that analyzed the weekly

  13. Osnovy formirovanija sistemy upravlenija riskami proektov innovacionnogo razvitija akvakul'tury v regione (Na primere Kaliningradskoj oblasti [The formation of a risk management system for projects in the field of aquaculture innovative development in the Kaliningrad region: a case study

    Directory of Open Access Journals (Sweden)

    Serbulov Alexey

    2012-01-01

    Full Text Available This article sets out to develop the concept and the principal scheme of the formation of a risk management system for innovative economic development projects in the field of aquaculture. The research carried out by the authors helps identify the main problems and characteristics of risk management projects for the development of aquaculture in presentday Russia. The authors outline the status and features of aquaculture development projects in the North-western federal district and the Kaliningrad region. The article formulates and justifies the concept of “risk management projects in innovative development of aquaculture in the region” focusing on the classification of aquaculture risks in relation to innovative development projects, which expands the conceptual framework of risk management in view of the specific risks relating to economic development projects in the field of aquaculture. The authors characterize modern methods and approaches to risk management projects and organizations in the context of their application in the framework of aquaculture development projects and offer mechanisms for risk management of aquaculture development projects, which make it possible to include risk management activity in the general context of activities of parent project organizations. The authors develop the concept and principal scheme of the formation of risk management system for innovative development projects in aquaculture.

  14. Soil formation.

    NARCIS (Netherlands)

    Breemen, van N.; Buurman, P.

    1998-01-01

    Soil Formation deals with qualitative and quantitative aspects of soil formation (or pedogenesis) and the underlying chemical, biological, and physical processes. The starting point of the text is the process - and not soil classification. Effects of weathering and new formation of minerals,

  15. Direct comparison of the histidine-rich protein-2 enzyme-linked immunosorbent assay (HRP-2 ELISA) and malaria SYBR green I fluorescence (MSF) drug sensitivity tests in Plasmodium falciparum reference clones and fresh ex vivo field isolates from Cambodia.

    Science.gov (United States)

    Chaorattanakawee, Suwanna; Tyner, Stuart D; Lon, Chanthap; Yingyuen, Kritsanai; Ruttvisutinunt, Wiriya; Sundrakes, Siratchana; Sai-gnam, Piyaporn; Johnson, Jacob D; Walsh, Douglas S; Saunders, David L; Lanteri, Charlotte A

    2013-07-12

    Performance of the histidine-rich protein-2 enzyme-linked immunosorbent assay (HRP-2 ELISA) and malaria SYBR Green I fluorescence (MSF) drug sensitivity tests were directly compared using Plasmodium falciparum reference strains and fresh ex vivo isolates from Cambodia against a panel of standard anti-malarials. The objective was to determine which of these two common assays is more appropriate for studying drug susceptibility of "immediate ex vivo" (IEV) isolates, analysed without culture adaption, in a region of relatively low malaria transmission. Using the HRP-2 and MSF methods, the 50% inhibitory concentration (IC50) values against a panel of malaria drugs were determined for P. falciparum reference clones (W2, D6, 3D7 and K1) and 41 IEV clinical isolates from an area of multidrug resistance in Cambodia. Comparison of the IC50 values from the two methods was made using Wilcoxon matched pair tests and Pearson's correlation. The lower limit of parasitaemia detection for both methods was determined for reference clones and IEV isolates. Since human white blood cell (WBC) DNA in clinical samples is known to reduce MSF assay sensitivity, SYBR Green I fluorescence linearity of P. falciparum samples spiked with WBCs was evaluated to assess the relative degree to which MSF sensitivity is reduced in clinical samples. IC50 values correlated well between the HRP-2 and MSF methods when testing either P. falciparum reference clones or IEV isolates against 4-aminoquinolines (chloroquine, piperaquine and quinine) and the quinoline methanol mefloquine (Pearson r = 0.85-0.99 for reference clones and 0.56-0.84 for IEV isolates), whereas a weaker IC50 value correlation between methods was noted when testing artemisinins against reference clones and lack of correlation when testing IEV isolates. The HRP-2 ELISA produced a higher overall success rate (90% for producing IC50 best-fit sigmoidal curves), relative to only a 40% success rate for the MSF assay, when evaluating ex

  16. Fracture corridors as seal-bypass systems in siliciclastic reservoir-cap rock successions: Field-based insights from the Jurassic Entrada Formation (SE Utah, USA)

    Science.gov (United States)

    Ogata, Kei; Senger, Kim; Braathen, Alvar; Tveranger, Jan

    2014-09-01

    Closely spaced, sub-parallel fracture networks contained within localized tabular zones that are fracture corridors may compromise top seal integrity and form pathways for vertical fluid flow between reservoirs at different stratigraphic levels. This geometry is exemplified by fracture corridors found in outcrops of the Jurassic Entrada Formation in Utah (USA). These fracture corridors exhibit discolored (bleached) zones, interpreted as evidence of ancient fracture-enhanced circulation of reducing fluids within an exhumed siliciclastic reservoir-cap rock succession. Extensive structural and stratigraphic mapping and logging provided fracture data for analysis with respect to their occurrence and relationships to larger faults and folds. Three types of fracture corridors, representing end-members of a continuum of possibly interrelated structures were identified: 1) fault damage zone including segment relays; 2) fault-tip process zone; and 3) fold-related crestal-zone fracture corridors. The three types exhibit intrinsic orientations and patterns, which in sum define a local- to regional network of inferred vertical and lateral, high-permeability conduits. The results from our analysis may provide improved basis for the evaluation of trap integrity and flow paths across the reservoir-cap rock interface, applicable to both CO2 storage operations and the hydrocarbon industry.

  17. Influence of oil and gas field operations on spatial and temporal distributions of atmospheric non-methane hydrocarbons and their effect on ozone formation in winter

    Science.gov (United States)

    Field, R. A.; Soltis, J.; McCarthy, M. C.; Murphy, S.; Montague, D. C.

    2015-03-01

    Emissions from oil and natural gas development during winter in the Upper Green River basin of Wyoming are known to drive episodic ozone (O3) production. Contrasting O3 distributions were observed in the winters of 2011 and 2012, with numerous episodes (hourly O3 ≥ 85 ppbv) in 2011 compared to none in 2012. The lack of O3 episodes in 2012 coincided with a reduction in measured ambient levels of total non-methane hydrocarbons (NMHC). Measurements of speciated NMHC, and other air quality parameters, were performed to better understand emission sources and to determine which compounds are most active in promoting O3 formation. Positive matrix factorization (PMF) analyses of the data were carried out to help achieve these goals. PMF analyses revealed three contributing factors that were identified with different emission source types: factor 1, combustion/traffic; factor 2, fugitive natural gas; and factor 3, fugitive condensate. Compositional signatures of the three contributing factors were identified through comparison with independently derived emission source profiles. Fugitive emissions of natural gas and of condensate were the two principal emission source types for NMHC. A water treatment and recycling facility was found to be a significant source of NMHC that are abundant in condensate, in particular toluene and m+p-xylene. Emissions from water treatment have an influence upon peak O3 mixing ratios at downwind measurement sites.

  18. Radiochemical problems of radiation chemical synthesis in n,. gamma. -field of nuclear reactor. 1. Formation and accumulation of chemically non-separable radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Mironov, V.P.; Freidus, N.V.; Bugaenko, L.T.; Kalyazin, E.P.; Petryaev, E.P.

    1981-01-01

    A wide applicability of products of radiation chemical synthesis (RCS), using n, ..gamma..-irradiation, is limited by possible contamination of the latter with long-lived radioactive isotopes of chemical elements included in the composition of the reagent and compounds synthesized (chemically non-separable radionuclides - CNR). A technique of the determination of the limit accumulation CNR on the basis of radiation chemical parameters of the synthesis (radiation-chemical yield, the dose rate absorbed, singleness of purpose of RCS etc.) and radiochemical parameters of formation and accumulation of CNR (radiochemical yields of CNR in the products of radiolysis, neutron fluence, the reagent purity etc.) is suggested. The radiochemical evaluation of CNR accumulation (tritium and carbon-14), formed at the expense of activation with neutrons of chemical elements of water and organic substances, consisting of hydrogen, carbon and oxygen has shown that at relatively low yields of final products (> or approximately 3 molecules/100 eV) no accumulation of radionuclides in concentrations reaching the average admissible concentration takes place.

  19. Context Based Wikipedia Linking

    Science.gov (United States)

    Granitzer, Michael; Seifert, Christin; Zechner, Mario

    Automatically linking Wikipedia pages can be done either content based by exploiting word similarities or structure based by exploiting characteristics of the link graph. Our approach focuses on a content based strategy by detecting Wikipedia titles as link candidates and selecting the most relevant ones as links. The relevance calculation is based on the context, i.e. the surrounding text of a link candidate. Our goal was to evaluate the influence of the link-context on selecting relevant links and determining a links best-entry-point. Results show, that a whole Wikipedia page provides the best context for resolving link and that straight forward inverse document frequency based scoring of anchor texts achieves around 4% less Mean Average Precision on the provided data set.

  20. Field Evaluation of Melolure, a Formate Analogue of Cuelure, and Reassessment of Fruit Fly Species Trapped in Sydney, New South Wales, Australia.

    Science.gov (United States)

    Dominiak, Bernard C; Campbell, Angus J; Jang, Eric B; Ramsey, Amanda; Fanson, Benjamin G

    2015-06-01

    In Australia, tephritids are usually attracted to either cuelure or methyl eugenol. Methyl eugenol is a very effective lure, but cuelure is less effective likely due to low volatility. A new formate analogue of cuelure, melolure, has increased volatility, resulting in improved efficacy with the melon fruit fly, Bactrocera cucurbitae Coquillett. We tested the efficacy of melolure with fruit fly species in Sydney as part of the National Exotic Fruit Fly Monitoring programme. This monitoring programme has 71 trap sites across Sydney, with each trap site comprising separate Lynfield traps containing either cuelure, methyl eugenol, or capilure lure. In 2008, an additional Lynfield trap with melolure plugs was added to seven sites. In 2009 and 2010, an additional Lynfield trap with melolure wicks was added to 11 trap sites and traps were monitored fortnightly for 2 yr. Capture rates for melolure traps were similar to cuelure traps for Dacus absonifacies (May) and Dacus aequalis (Coquillet), but melolure traps consistently caught fewer Bactrocera tryoni (Froggatt) than cuelure traps. However, trap sites with both a cuelure and melolure traps had increased capture rates for D. absonifacies and D. aequalis, and a marginally significant increase for B. tryoni. Melolure plugs were less effective than melolure wicks, but this effect may be related to lure concentration. The broader Bactrocera group species were attracted more to cuelure than melolure while the Dacus group species were attracted more to melolure than cuelure. There is no benefit in switching from cuelure to melolure to monitor B. tryoni, the most important fruit fly pest in Australia. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. Tokamak formation and sustainment by tokamak injection

    International Nuclear Information System (INIS)

    Farengo, R.; Jarboe, T.R.

    1991-01-01

    The authors propose here a new helicity injection method for tokamak formation and sustainment that has high efficiency, conserves toroidal symmetry and is inductively driven. The basic idea is to inject a small tokamak (source tokamak) into a larger tokamak (steady tokamak). This current drive scheme eliminates the need for the ohmic heating transformer in the steady tokamak allowing the formation of very small aspect ratio tokamaks (Spherical Tori). Thus, steady state operation and high beta can be realized simultaneously. The method can also be applied to a larger aspect ratio tokamak and used in conjunction with the standard inductive formation technique. In order to allow for translation the ohmic heating coil used to produce the source tokamaks must be fed from one end (as in the CSS device) and the toroidal field coil must link both tokamaks. After formation the source tokamaks are accelerated towards the steady tokamak by a mirror field and the tension of the field lines that wrap around both tokamaks (producing a doublet type configuration). In a tokamak the helicity is proportional to the current. This indicates that (assuming helicity is conserved during the merging process) a steady state situation will result if the helicity supplied by the source tokamaks is equal to the helicity dissipated by the steady tokamak. Assuming that source tokamaks of helicity K s are injected with frequency f, the steady state condition can be written as: fK s = 2V t Ψ t = K t /τ K where V t , Ψ t , K t and τ K are the ohmic loop voltage, toroidal flux, helicity and helicity decay time of the steady tokamak. A simple calculation shows that the DIII-D tokamak could be sustained by injecting source tokamaks with R = 1.20 m, a = 0.23 m and I = 151 kA at a frequency of 120 Hz. 1 ref

  2. Manuel UNIMARC format bibliographique

    CERN Document Server

    2007-01-01

    This manual is the French translation of the second edition of UNIMARC Manual: bibliographic format published in English in 1994 and completed by 5 updates published from 1996 to 2005. This 5th French edition is composite. It reproduces identically a part of the 4th edition published in 2002 and, for the fields of the format modified in the Update 5, it offers a new more structured presentation. This is a handbook dedicated to French-speaking users of the UNIMARC format for bibliographic descriptions.

  3. Link mining models, algorithms, and applications

    CERN Document Server

    Yu, Philip S; Faloutsos, Christos

    2010-01-01

    This book presents in-depth surveys and systematic discussions on models, algorithms and applications for link mining. Link mining is an important field of data mining. Traditional data mining focuses on 'flat' data in which each data object is represented as a fixed-length attribute vector. However, many real-world data sets are much richer in structure, involving objects of multiple types that are related to each other. Hence, recently link mining has become an emerging field of data mining, which has a high impact in various important applications such as text mining, social network analysi

  4. Device for Controlled Distribution of FePt Nanoparticles Formations in a Stream of Liquid Medium under Influence of Magnetic Field

    Directory of Open Access Journals (Sweden)

    Karolis ŠILEIKA

    2014-04-01

    Full Text Available In this research paper a design of magnetic device comprising Halbach arrays which maximizes the magnetic forces acting on magnetic nanoparticles and which can be used for successful steering of said particles to a zone of interest and captured thereat while exhibiting a certain flow and accumulation pattern after injection into a stream of a liquid medium is presented. The aim was to investigate efficiency of such design of a magnetic device for application in magnetic targeting techniques. The presented construction was assembled from 10 magnetic elements having the same dimensions and residual magnetic field, and casing of Plexiglas material. Aggregating of clusters of FePt nanoparticles was evidently successful at preferable region located between two opposing parts of a magnetic device, which was tested for flow rates of (1 – 10 mL/min of main stream medium. To simulate the viscosity of blood a 1.5 % PVP 90 solution was used as the flowing medium. The shallow depth of targeting was chosen for practical reason: to ensure a maximum visibility of particle "steering" pattern obtainable by the magnetic device consisting of two adjacent parts comprising Halbach arrays. DOI: http://dx.doi.org/10.5755/j01.ms.20.1.3371

  5. Instability and electrical response of small laminar coflow diffusion flames under AC electric fields: Toroidal vortex formation and oscillating and spinning flames

    KAUST Repository

    Xiong, Yuan

    2016-06-24

    Dynamical and electrical responses of a small coflow diffusion flame were investigated by applying a high-voltage alternating current (AC), to a fuel jet nozzle. High-speed imaging and electrical diagnostics were adopted to capture flame dynamics and electrical signals, such as voltage (V ), frequency (f ) and current (I ). In the V -f domain of 0-5kV and 0-5kHz, AC-driven instabilities, resulting in various flame modes such as an oscillation, pinch-off and spinning of flames were identified. Characteristic frequency of each mode was determined and a visualization of near-nozzle flow structures suggested a close causality of initial counter-rotating vortices (inner and outer toroidal vortices - ITV and OTV), to the other observed flame. An axisymmetric ITV shedding was identified within oscillating and pinch-off modes, while asymmetric ITV shedding was identified with the spinning mode. Integrated electric power over several AC periods correlated well with variation in the flame surface area for these instabilities, demonstrating that measured electric power is a potential indicator of combustion instabilities in electric-field-assisted combustion.

  6. Linking to the Future

    Science.gov (United States)

    Moore, John W.

    1999-09-01

    When I began subscribing to this Journal, I was an undergraduate chemistry major. One of my professors suggested that I should read JCE because I had expressed interest in both chemistry and teaching. I did so, and I have never regretted subscribing. To me the Journal seemed an incredible bargain. It cost less than a textbook and brought a similar quantity of information each yearand that information was often presented in a more interesting fashion than I was used to in textbooks. As we move into a new millennium, it is useful to reflect on what a current undergraduate with interests in chemistry and teaching might expect of this Journal. How should the Journal develop over the next decades to serve that student most effectively? Younger readers are often more attuned to computers and information technology than are their elders. They expecteven demanda format that recognizes and adapts to the advantages and opportunities presented by such new media. This is a good thing, because by adapting to these readers' interests, this Journal can continue to grow with the times, serving all of us better. During the past decade it has become clear that the print medium can deliver only a fraction of the broad range of information that you or I could use effectively to help students learn. Chemistry content and learning aids are no longer limited to what can be printed on paper, and even what can be printed is often more useful in electronic format. My goal for this Journal is to make use of various ways to deliver information, capitalizing on the strengths of each, but also accommodating the experience and interests of a broad range of readers. We recognize that no single medium is best for all our content or all our clientele, and we are working toward a seamless integration of everything our authors contribute to JCE. We want you to be able to find what interests you, obtain and peruse it in an appropriate format, and use it effectively with students. I like to get my copy

  7. Effects of metallicity, star-formation conditions, and evolution in B and Be stars. II. Small Magellanic Cloud, field of NGC 330

    Science.gov (United States)

    Martayan, C.; Frémat, Y.; Hubert, A.-M.; Floquet, M.; Zorec, J.; Neiner, C.

    2007-02-01

    Aims:We search for the effects of metallicity on B and Be stars in the Small and Large Magellanic Clouds (SMC and LMC) and in the Milky Way (MW), by extending our previous analysis of B and Be star populations in the LMC to the SMC. The rotational velocities of massive stars and the evolutionary status of Be stars are examined with respect to their environments. Methods: Spectroscopic observations of hot stars belonging to the young cluster SMC-NGC 330 and its surrounding region were obtained with the VLT-GIRAFFE facilities in MEDUSA mode. We determined fundamental parameters for B and Be stars with the GIRFIT code, taking the effect of fast rotation and the age of observed clusters into account. We compared the mean V sin i obtained by spectral type- and mass-selection for field and cluster B and Be stars in the SMC with the one in the LMC and MW. Results: We find that (i) B and Be stars rotate faster in the SMC than in the LMC and in the LMC than in the MW; (ii) at a given metallicity, Be stars begin their main sequence life with a higher initial rotational velocity than B stars. Consequently, only a fraction of the B stars that reach the ZAMS with a sufficiently high initial rotational velocity can become Be stars; (iii) the distributions of initial rotational velocities at the ZAMS for Be stars in the SMC, LMC, and MW are mass- and metallicity-dependent; (iv) the angular velocities of B and Be stars are higher in the SMC than in the LMC and MW; (v) in the SMC and LMC, massive Be stars appear in the second part of the main sequence, in contrast to massive Be stars in the MW. Tables 1-6, 8 and 11 are only available in electronic form at http://www.aanda.org

  8. MORPHOLOGICAL PROPERTIES OF Lyα EMITTERS AT REDSHIFT 4.86 IN THE COSMOS FIELD: CLUMPY STAR FORMATION OR MERGER?

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Masakazu A. R.; Taniguchi, Yoshiaki; Kajisawa, Masaru; Shioya, Yasuhiro; Nagao, Tohru [Research Center for Space and Cosmic Evolution, Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577 (Japan); Murata, Katsuhiro L. [Department of Physics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602 (Japan); Koekemoer, Anton M. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Murayama, Takashi [Astronomical Institute, Graduate School of Science, Tohoku University, Aramaki, Aoba, Sendai 980-8578 (Japan); Scoville, Nick Z.; Capak, Peter L., E-mail: kobayashi@cosmos.phys.sci.ehime-u.ac.jp [Department of Astronomy, MS 105-24, California Institute of Technology, Pasadena, CA 91125 (United States)

    2016-03-01

    We investigate morphological properties of 61 Lyα emitters (LAEs) at z = 4.86 identified in the COSMOS field, based on Hubble Space Telescope Advanced Camera for Surveys (ACS) imaging data in the F814W band. Out of the 61 LAEs, we find the ACS counterparts for 54 LAEs. Eight LAEs show double-component structures with a mean projected separation of 0.″63 (∼4.0 kpc at z = 4.86). Considering the faintness of these ACS sources, we carefully evaluate their morphological properties, that is, size and ellipticity. While some of them are compact and indistinguishable from the point-spread function (PSF) half-light radius of 0.″07 (∼0.45 kpc), the others are clearly larger than the PSF size and spatially extended up to 0.″3 (∼1.9 kpc). We find that the ACS sources show a positive correlation between ellipticity and size and that the ACS sources with large size and round shape are absent. Our Monte Carlo simulation suggests that the correlation can be explained by (1) the deformation effects via PSF broadening and shot noise or (2) the source blending in which two or more sources with small separation are blended in our ACS image and detected as a single elongated source. Therefore, the 46 single-component LAEs could contain the sources that consist of double (or multiple) components with small spatial separation (i.e., ≲0.″3 or 1.9 kpc). Further observation with high angular resolution at longer wavelengths (e.g., rest-frame wavelengths of ≳4000 Å) is inevitable to decipher which interpretation is adequate for our LAE sample.

  9. Efficacy of the Combination of a PARP Inhibitor and UVC on Cancer Cells as Imaged by Focus Formation by the DNA Repair-related Protein 53BP1 Linked to Green Fluorescent Protein.

    Science.gov (United States)

    Tome, Yasunori; Uehara, Fuminari; Miwa, Shinji; Yano, Shuya; Mii, Sumiyuki; Efimova, Elena V; Bouvet, Michael; Kimura, Hiroaki; Tsuchiya, Hiroyuki; Kanaya, Fuminori; Hoffman, Robert M

    2016-08-01

    The ability to image DNA repair in cancer cells after irradiation, as well as its inhibition by potential therapeutic agents, is important for the further development of effective cancer therapy. 53BP1 is a DNA repair protein that is overexpressed and forms foci when double-stranded DNA breaks occur in DNA. The re-localization of green fluorescent protein (GFP) fused to the chromatin-binding domain of 53BP1 to form foci was imaged after UVC irradiation of breast and pancreatic cancer cells expressing 53BP1-GFP using confocal microscopy. During live-cell imaging, 53BP1-GFP focus formation was observed within 10 minutes after UVC irradiation. Most 53BP1 foci resolved by 100 minutes. To block UVC-induced double-strand break repair in cancer cells, poly(ADP-ribose) polymerase (PARP) was targeted with ABT-888 (veliparib). PARP inhibition markedly enhanced UVC-irradiation-induced persistence of 53BP1-foci, even beyond 100 minutes after UVC irradiation, and reduced proliferation of breast and pancreatic cancer cells. Confocal microscopy of 53BP1-GFP is a powerful method for imaging UVC-induced DNA damage and repair, as well as inhibition of repair. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  10. An Accurate Link Correlation Estimator for Improving Wireless Protocol Performance

    Directory of Open Access Journals (Sweden)

    Zhiwei Zhao

    2015-02-01

    Full Text Available Wireless link correlation has shown significant impact on the performance of various sensor network protocols. Many works have been devoted to exploiting link correlation for protocol improvements. However, the effectiveness of these designs heavily relies on the accuracy of link correlation measurement. In this paper, we investigate state-of-the-art link correlation measurement and analyze the limitations of existing works. We then propose a novel lightweight and accurate link correlation estimation (LACE approach based on the reasoning of link correlation formation. LACE combines both long-term and short-term link behaviors for link correlation estimation. We implement LACE as a stand-alone interface in TinyOS and incorporate it into both routing and flooding protocols. Simulation and testbed results show that LACE: (1 achieves more accurate and lightweight link correlation measurements than the state-of-the-art work; and (2 greatly improves the performance of protocols exploiting link correlation.

  11. A statistical model for telecommunication link design

    Science.gov (United States)

    Yuen, J. H.

    1975-01-01

    An evaluation is conducted of the current telecommunication link design technique and a description is presented of an alternative method, called the probability distribution method (PDM), which is free of the disadvantages of the current technique while retaining its advantages. The PDM preserves the simplicity of the design control table (DCT) format. The use of the DCT as a management design control tool is continued. The telecommunication link margin probability density function used presents the probability of achieving any particular value of link performance. It is, therefore, possible to assess the performance risk and other tradeoffs.

  12. Dynamic link: user's manual

    International Nuclear Information System (INIS)

    Harada, Hiroo; Asai, Kiyoshi; Kihara, Kazuhisa.

    1981-09-01

    The purpose of dynamic link facility is to link a load module dynamically only when it is used in execution time. The facility is very useful for development, execution and maintenance of a large scale computer program which is too big to be saved as one load module in main memory, or it is poor economy to save it due to many unused subroutines depending on an input. It is also useful for standardization and common utilization of programs. Standard usage of dynamic link facility of FACOM M-200 computer system, a software tool which analyzes the effect of dynamic link facility and application of dynamic link to nuclear codes are described. (author)

  13. Predicting Porosity and Permeability for the Canyon Formation, SACROC Unit (Kelly-Snyder Field), Using the Geologic Analysis via Maximum Likelihood System

    International Nuclear Information System (INIS)

    Reinaldo Gonzalez; Scott R. Reeves; Eric Eslinger

    2007-01-01

    -based, probabilistic clustering analysis procedure is successfully applied to generate a high-resolution reservoir characterization outcome. The approach was applied in the Pennsylvanian-Permian reef carbonates (Cisco and Canyon Formations) of a subregion of the SACROC Unit, Horseshoe Atoll, Permian Basin, Texas, and acknowledged as a highly complex carbonate reservoir. Due to the modest results achieved with the application of soft-computing methodologies to the available information (no crosswell data at hand), the original project target about creating a data-driven device relating surface seismic information, crosswell seismic attributes, geophysical logs and core parameters for the prediction of core-scale porosity and permeability profiles in locations where only 3D surface seismic data was available, had to be reformulated. It was shown that 3D seismic information was not capable of capturing the degree of vertical variability of SACROC. As a consequence, available seismic information was unincorporated from posterior reservoir characterization tasks, and a combination of data-driven procedures and geostatistical methods was utilized for reservoir characterization purposes. A selected area within the SACROC Unit platform was used for this study. The suitable logs for the creation of an 'intelligent' log-to-core device were not present for all wells. These logs were gamma ray (GR), neutron porosity (NPHI), bulk density (RHOB), and delta time (DT). It was necessary to create a first 'intelligent' tool, a log-to-log model to provide synthetic logs of RHOB and DT (or eventually of acoustic impedance derived from them) at well locations where only GR and NPHI were available (the most common situation in this reservoir). Once the 'ideal' logs were completed, a second model, a log-to-core device, provides core scale estimates of porosity and permeability (P and P). The validity of these soft-computing devices was checked using 'holdout' wells. In this way, 'core' parameter profiles

  14. Biogeographic patterns of microbial communities from different oil-contaminated fields in China

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Yuting; Li, Guanghe [School of Environment, Tsinghua University (China); Zhou, Ji zhong [Institute for Environmental Genomics, Department of Botany and Microbiology, University of Oklahoma (United States)], email: jzhou@ou.edu

    2011-07-01

    Some striking biological challenges of the 21st century include linking biodiversity to ecosystem functions, information scaling, and linking genomics to ecology. This paper discusses the biogeographic patterns of microbial communities from various oil-contaminated fields in China. Two kinds of high throughput approaches are used, open format and closed format. Key differences between them are outlined. The GeoChip, or functional gene array (FGA) approach is presented. This is a high throughput tool for linking community structure to functions. Its main advantages are its high resolution and detecting functions. This approach was applied to soils, bioreactors and ground waters, among others. Issues related to specificity, sensitivity and quantification are listed. An overview of the microarray analysis is given. This is applied to the BP oil spill. 100 samples were chosen from representative oil fields to study the biogeographic patterns of microbial communities in China. The complete study is presented with the results.

  15. Galaxy formation and evolution

    CERN Document Server

    Mo, Houjun; White, Simon

    2010-01-01

    The rapidly expanding field of galaxy formation lies at the interface between astronomy, particle physics, and cosmology. Covering diverse topics from these disciplines, all of which are needed to understand how galaxies form and evolve, this book is ideal for researchers entering the field. Individual chapters explore the evolution of the Universe as a whole and its particle and radiation content; linear and nonlinear growth of cosmic structure; processes affecting the gaseous and dark matter components of galaxies and their stellar populations; the formation of spiral and elliptical galaxies; central supermassive black holes and the activity associated with them; galaxy interactions; and the intergalactic medium. Emphasizing both observational and theoretical aspects, this book provides a coherent introduction for astronomers, cosmologists, and astroparticle physicists to the broad range of science underlying the formation and evolution of galaxies.

  16. Preparation and characterization of platinum(II) and (IV) complexes of 1,3-diaminepropane and 1,4-diaminebutane: circumvention of cisplatin resistance and DNA interstrand cross-link formation in CH1cisR ovarian tumor cells.

    Science.gov (United States)

    Alvarez-Valdés, Amparo; Pérez, José Manuel; López-Solera, Isabel; Lannegrand, Raúl; Continente, José Manuel; Amo-Ochoa, Pilar; Camazón, María José; Solans, Xavier; Font-Bardía, Mercè; Navarro-Ranninger, Carmen

    2002-04-25

    The reaction of Pt(dimethyl sulfoxide)(2)CBDCA (CBDCA = 1,1-cyclobutanedicarboxylate) with 1,4-diaminebutane and 1,3-diaminepropane ligands yields, under certain conditions, new [Pt(diamine)(2)]CBDCA complexes (1a,b), where the CBDCA ligand has been removed from the coordination sphere of the platinum atom by the diamine ligand, instead of forming the expected [Pt(diamine)CBDCA] complexes (1'a,b). The structure of complexes 1a and 1'b was solved by X-ray diffraction. Complex 1a crystallizes in the orthorhombic system, in the noncentrosymmetric C222 space group, with unit cell parameters: a = 20.053(2) A; b = 8.655(2) A, c = 5.711(3) A; V = 991.2(6) A(3); delta (calcd) = 1.627 mg/m(3); and R = 0.050. The Pt atom displays an unexpected distorted tetrahedral coordination with a N-Pt-N inner bond angle equal to 81(2) degrees for N atoms of the same 1,3-propanediamine ligand and a N-Pt-N bond angle for different ligands equal to 135.4(9) degrees. Complex 1'b crystallizes in the monoclinic system, in the centrosymmetric P2(1)/c space group, with unit cell parameters: a = 6.007(2) A; b = 15.336(4) A, c = 13.232(5) A; beta = 101.90(3) degrees; V = 1192.8(7) A(3); delta (calcd) = 2.369 mg/m(3); and R = 0.067. Cytotoxicity data show that of all the synthesized compounds, only complexes 1'a and 1'b exhibit remarkable cytotoxic properties. Thus, in contrast with carboplatin (cis-diammine-1,1-cyclobutane dicarboxilatoplatinum(II)), compounds 1'a and 1'b, which also contain the CBDCA ligand, are able to circumvent cisplatin (cis-diamminedichloroplatinum(II)) resistance in several tumor cells. Moreover, after 24 h of incubation of CH1cisR ovarian tumor cells with 10 microM of compounds 1'a and 1'b, the level of DNA interstrand cross-links (ICLs) induced by compounds 1'a and 1'b is 3.3 and 3.8 times higher, respectively, than that of carboplatin and 3.5 and 4.0 times higher, respectively, than that of cisplatin. Interestingly, under the same conditions, the intracellular

  17. Satellite formation flying relative dynamics, formation design, fuel optimal maneuvers and formation maintenance

    CERN Document Server

    Wang, Danwei; Poh, Eng Kee

    2017-01-01

    This book systematically describes the concepts and principles for multi-satellite relative motion, passive and near passive formation designs, trajectory planning and control for fuel optimal formation maneuvers, and formation flying maintenance control design. As such, it provides a sound foundation for researchers and engineers in this field to develop further theories and pursue their implementations. Though satellite formation flying is widely considered to be a major advance in space technology, there are few systematic treatments of the topic in the literature. Addressing that gap, the book offers a valuable resource for academics, researchers, postgraduate students and practitioners in the field of satellite science and engineering.

  18. Visualisierung von typisierten Links in Linked Data

    Directory of Open Access Journals (Sweden)

    Georg Neubauer

    2017-09-01

    Full Text Available Das Themengebiet der Arbeit behandelt Visualisierungen von typisierten Links in Linked Data. Die wissenschaftlichen Gebiete, die im Allgemeinen den Inhalt des Beitrags abgrenzen, sind das Semantic Web, das Web of Data und Informationsvisualisierung. Das Semantic Web, das von Tim Berners Lee 2001 erfunden wurde, stellt eine Erweiterung zum World Wide Web (Web 2.0 dar. Aktuelle Forschungen beziehen sich auf die Verknüpfbarkeit von Informationen im World Wide Web. Um es zu ermöglichen, solche Verbindungen wahrnehmen und verarbeiten zu können sind Visualisierungen die wichtigsten Anforderungen als Hauptteil der Datenverarbeitung. Im Zusammenhang mit dem Sematic Web werden Repräsentationen von zuhammenhängenden Informationen anhand von Graphen gehandhabt. Der Grund des Entstehens dieser Arbeit ist in erster Linie die Beschreibung der Gestaltung von Linked Data-Visualisierungskonzepten, deren Prinzipien im Rahmen einer theoretischen Annäherung eingeführt werden. Anhand des Kontexts führt eine schrittweise Erweiterung der Informationen mit dem Ziel, praktische Richtlinien anzubieten, zur Vernetzung dieser ausgearbeiteten Gestaltungsrichtlinien. Indem die Entwürfe zweier alternativer Visualisierungen einer standardisierten Webapplikation beschrieben werden, die Linked Data als Netzwerk visualisiert, konnte ein Test durchgeführt werden, der deren Kompatibilität zum Inhalt hatte. Der praktische Teil behandelt daher die Designphase, die Resultate, und zukünftige Anforderungen des Projektes, die durch die Testung ausgearbeitet wurden.

  19. Linking open vocabularies

    CERN Document Server

    Greifender, Elke; Seadle, Michael

    2013-01-01

    Linked Data (LD), Linked Open Data (LOD) and generating a web of data, present the new knowledge sharing frontier. In a philosophical context, LD is an evolving environment that reflects humankinds' desire to understand the world by drawing on the latest technologies and capabilities of the time. LD, while seemingly a new phenomenon did not emerge overnight; rather it represents the natural progression by which knowledge structures are developed, used, and shared. Linked Open Vocabularies is a significant trajectory of LD. Linked Open Vocabularies targets vocabularies that have traditionally b

  20. Radiation-induced linking reactions in polyethylene

    International Nuclear Information System (INIS)

    Zoepfl, F.J.

    1983-01-01

    Three types of measurements are reported relating to chemical reactions in polyethylene induced by ionizing radiation: 1) visco