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Sample records for length density profiles

  1. Scattering length density profile of Ni film under controlled corrosion ...

    Indian Academy of Sciences (India)

    Abstract. We report the density depth profile of an as-deposited Ni film and density profile for the same film after controlled electrochemical corrosion by chloride ions, mea- sured by unpolarized neutron reflectometry. The neutron reflectometry measurement of the film after corrosion shows density degradation along the ...

  2. Scattering length density profile of Ni film under controlled corrosion ...

    Indian Academy of Sciences (India)

    We report the density depth profile of an as-deposited Ni film and density profile for the same film after controlled electrochemical corrosion by chloride ions, measured by unpolarized neutron reflectometry. The neutron reflectometry measurement of the film after corrosion shows density degradation along the thickness of ...

  3. Scattering length density profile of Ni film under controlled corrosion ...

    Indian Academy of Sciences (India)

    the fundamental aspects of the mechanisms operating in the early stages of pitting. (leading to passivity breakdown ... The sample thickness was monitored by quartz crystal system during growth. The electrochemical ... system, N is the number density at a depth z and b is the coherent nuclear scat- tering length. From the ...

  4. Two aspects of thin film analysis: boron profile and scattering length density profile

    Energy Technology Data Exchange (ETDEWEB)

    Chen-Mayer, H.H. E-mail: chen-mayer@nist.gov; Lamaze, G.P.; Coakley, K.J.; Satija, S.K

    2003-06-01

    Boron/phosphorus-doped silicate glass (BPSG) thin films are widely used in microelectronic circuit devices. We employ two neutron techniques to investigate a 200-nm thick BPSG film: neutron depth profiling (NDP) and neutron reflectometry (NR) to obtain complementary information on the boron containing layer.

  5. Density profile of terminally attached polymer chains

    International Nuclear Information System (INIS)

    Venema, P.; Odijk, T.

    1992-01-01

    Scaling theory hypothesizes a step-function profile for the segment density of polymer chains terminally attached to a planar wall. Using a self-consistent-field theory we give a perturbation analysis of the first-order correction to the step-function profile in order to gauge the impact of a possible tail. The new profile decays smoothly to zero without a discontinuity in the derivative (except near the wall). The segment density profile as scaled by the amplitude of the step-function profile has a tail that decays essentially as 1/βz*2, with β a dimensionless parameter and z* the distance from the wall scaled by the step length of the step-function profile. A scaling analysis would yield z*-4/3. 13 refs., 4 figs

  6. Minimal length, Friedmann equations and maximum density

    International Nuclear Information System (INIS)

    Awad, Adel; Ali, Ahmed Farag

    2014-01-01

    Inspired by Jacobson’s thermodynamic approach, Cai et al. have shown the emergence of Friedmann equations from the first law of thermodynamics. We extend Akbar-Cai derivation http://dx.doi.org/10.1103/PhysRevD.75.084003 of Friedmann equations to accommodate a general entropy-area law. Studying the resulted Friedmann equations using a specific entropy-area law, which is motivated by the generalized uncertainty principle (GUP), reveals the existence of a maximum energy density closed to Planck density. Allowing for a general continuous pressure p(ρ,a) leads to bounded curvature invariants and a general nonsingular evolution. In this case, the maximum energy density is reached in a finite time and there is no cosmological evolution beyond this point which leaves the big bang singularity inaccessible from a spacetime prospective. The existence of maximum energy density and a general nonsingular evolution is independent of the equation of state and the spacial curvature k. As an example we study the evolution of the equation of state p=ωρ through its phase-space diagram to show the existence of a maximum energy which is reachable in a finite time.

  7. Minimal length, Friedmann equations and maximum density

    Energy Technology Data Exchange (ETDEWEB)

    Awad, Adel [Center for Theoretical Physics, British University of Egypt,Sherouk City 11837, P.O. Box 43 (Egypt); Department of Physics, Faculty of Science, Ain Shams University,Cairo, 11566 (Egypt); Ali, Ahmed Farag [Centre for Fundamental Physics, Zewail City of Science and Technology,Sheikh Zayed, 12588, Giza (Egypt); Department of Physics, Faculty of Science, Benha University,Benha, 13518 (Egypt)

    2014-06-16

    Inspired by Jacobson’s thermodynamic approach, Cai et al. have shown the emergence of Friedmann equations from the first law of thermodynamics. We extend Akbar-Cai derivation http://dx.doi.org/10.1103/PhysRevD.75.084003 of Friedmann equations to accommodate a general entropy-area law. Studying the resulted Friedmann equations using a specific entropy-area law, which is motivated by the generalized uncertainty principle (GUP), reveals the existence of a maximum energy density closed to Planck density. Allowing for a general continuous pressure p(ρ,a) leads to bounded curvature invariants and a general nonsingular evolution. In this case, the maximum energy density is reached in a finite time and there is no cosmological evolution beyond this point which leaves the big bang singularity inaccessible from a spacetime prospective. The existence of maximum energy density and a general nonsingular evolution is independent of the equation of state and the spacial curvature k. As an example we study the evolution of the equation of state p=ωρ through its phase-space diagram to show the existence of a maximum energy which is reachable in a finite time.

  8. Variation of basic density and fibre length in Lonchocarpus capassa ...

    African Journals Online (AJOL)

    Within tree radial and axial variations of wood basic density and fibre length of. Lonchocarpus capassa (Rolfe) were investigated using three mature defect free trees from Kilosa District, Tanzania. Samples for determination of wood basic density and fibre length were collected from the butt, the middle and the tip of the

  9. Chemical theory and modelling through density across length scales

    International Nuclear Information System (INIS)

    Ghosh, Swapan K.

    2016-01-01

    One of the concepts that has played a major role in the conceptual as well as computational developments covering all the length scales of interest in a number of areas of chemistry, physics, chemical engineering and materials science is the concept of single-particle density. Density functional theory has been a versatile tool for the description of many-particle systems across length scales. Thus, in the microscopic length scale, an electron density based description has played a major role in providing a deeper understanding of chemical binding in atoms, molecules and solids. Density concept has been used in the form of single particle number density in the intermediate mesoscopic length scale to obtain an appropriate picture of the equilibrium and dynamical processes, dealing with a wide class of problems involving interfacial science and soft condensed matter. In the macroscopic length scale, however, matter is usually treated as a continuous medium and a description using local mass density, energy density and other related property density functions has been found to be quite appropriate. The basic ideas underlying the versatile uses of the concept of density in the theory and modelling of materials and phenomena, as visualized across length scales, along with selected illustrative applications to some recent areas of research on hydrogen energy, soft matter, nucleation phenomena, isotope separation, and separation of mixture in condensed phase, will form the subject matter of the talk. (author)

  10. ?Linear Gas Jet with Tailored Density Profile"

    Energy Technology Data Exchange (ETDEWEB)

    KRISHNAN, Mahadevan

    2012-12-10

    Supersonic, highly collimated gas jets and gas-filled capillary discharge waveguides are two primary targets of choice for Laser Plasma Accelerators (LPA) . Present gas jets have lengths of only 2-4 mm at densities of 1-4E19 cm-3, sufficient for self trapping and electron acceleration to energies up to ~150 MeV. Capillary structures 3 cm long have been used to accelerate beams up to 1 GeV. Capillary discharges used in LPAs serve to guide the pump laser and optimize the energy gain. A wall-stabilized capillary discharge provides a transverse profile across the channel that helps guide the laser and combat diffraction. Gas injection via a fast nozzle at one end provides some longitudinal density control, to improve the coupling. Gas jets with uniform or controlled density profiles may be used to control electron bunch injection and are being integrated into capillary experiments to add tuning of density. The gas jet for electron injection has not yet been optimized. Our Ph-I results have provided the LPA community with an alternative path to realizing a 2-3GeV electron bunch using just a gas jet. For example, our slit/blade combination gives a 15-20mm long acceleration path with tunable density profile, serving as an alternative to a 20-mm long capillary discharge with gas injection at one end. In Ph-II, we will extend these results to longer nozzles, to see whether we can synthesize 30 or 40-mm long plasma channels for LPAs.

  11. Measurements of electron density profiles using an angular filter refractometer

    Energy Technology Data Exchange (ETDEWEB)

    Haberberger, D., E-mail: dhab@lle.rochester.edu; Ivancic, S.; Hu, S. X.; Boni, R.; Barczys, M.; Craxton, R. S.; Froula, D. H. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14636 (United States)

    2014-05-15

    A novel diagnostic technique, angular filter refractometry (AFR), has been developed to characterize high-density, long-scale-length plasmas relevant to high-energy-density physics experiments. AFR measures plasma densities up to 10{sup 21} cm{sup −3} with a 263-nm probe laser and is used to study the plasma expansion from CH foil and spherical targets that are irradiated with ∼9 kJ of ultraviolet (351-nm) laser energy in a 2-ns pulse. The data elucidate the temporal evolution of the plasma profile for the CH planar targets and the dependence of the plasma profile on target radius for CH spheres.

  12. Vacuum heating evaluation for plasmas of exponentially decreasing density profile

    International Nuclear Information System (INIS)

    Pestehe, S.J.; Mohammadnejad, M.

    2008-01-01

    Ultra-short pulse lasers have opened a regime of laser-plasma interaction where plasmas have scale lengths shorter than the laser wavelength and allow the possibility of generating near-solid density plasmas. The interaction of high-intensity laser beams with sharply bounded high-density and small scale length plasmas is considered. Absorption of the laser energy associated with the mechanism of dragging electrons out of the plasma into the vacuum and sending them back into the plasma with the electric field component along the density gradient, so called vacuum heating, is studied. An exponentially decreasing electron density profile is assumed. The vector potential of the electromagnetic field propagating through the plasma is calculated and the behaviour of the electric and magnetic components of the electromagnetic field is studied. The fraction of laser power absorbed in this process is calculated and plotted versus the laser beam incidence angle, illumination energy, and the plasma scale length

  13. Maximum length scale in density based topology optimization

    DEFF Research Database (Denmark)

    Lazarov, Boyan Stefanov; Wang, Fengwen

    2017-01-01

    The focus of this work is on two new techniques for imposing maximum length scale in topology optimization. Restrictions on the maximum length scale provide designers with full control over the optimized structure and open possibilities to tailor the optimized design for broader range...... of manufacturing processes by fulfilling the associated technological constraints. One of the proposed methods is based on combination of several filters and builds on top of the classical density filtering which can be viewed as a low pass filter applied to the design parametrization. The main idea...

  14. Research Notes Patterns of thorn length, density, type and colour in ...

    African Journals Online (AJOL)

    Research Notes Patterns of thorn length, density, type and colour in African Acacias. JJ Midgley, MA Botha, D Balfour. Abstract. In Acacia no trade-off occurs between thorn length and thorn density and no correlation exists between thorn length and leaf length. By relating thorn length and density to leaf length it is clear that ...

  15. Current density profile evolution in JET

    International Nuclear Information System (INIS)

    Stubberfield, P.M.; Balet, B.; Campbell, D.; Challis, C.D.; Cordey, J.G.; O'Rourke, J.; Hammett, G.; Schmidt, G.L.

    1989-01-01

    Simulation studies have been made of the current density profile evolution in discharges where the bootstrap current is expected to be significant. The changes predicted in the total current profile have been confirmed by comparison with experimental results. (author) 8 refs., 6 figs

  16. Density Functional Theory and Materials Modeling at Atomistic Length Scales

    Directory of Open Access Journals (Sweden)

    Swapan K. Ghosh

    2002-04-01

    Full Text Available Abstract: We discuss the basic concepts of density functional theory (DFT as applied to materials modeling in the microscopic, mesoscopic and macroscopic length scales. The picture that emerges is that of a single unified framework for the study of both quantum and classical systems. While for quantum DFT, the central equation is a one-particle Schrodinger-like Kohn-Sham equation, the classical DFT consists of Boltzmann type distributions, both corresponding to a system of noninteracting particles in the field of a density-dependent effective potential, the exact functional form of which is unknown. One therefore approximates the exchange-correlation potential for quantum systems and the excess free energy density functional or the direct correlation functions for classical systems. Illustrative applications of quantum DFT to microscopic modeling of molecular interaction and that of classical DFT to a mesoscopic modeling of soft condensed matter systems are highlighted.

  17. Effects of fine root length density and root biomass on soil preferential flow in forest ecosystems

    Directory of Open Access Journals (Sweden)

    Yinghu Zhang

    2015-04-01

    Full Text Available Aim of study: The study was conducted to characterize the impacts of plant roots systems (e.g., root length density and root biomass on soil preferential flow in forest ecosystems. Area of study: The study was carried out in Jiufeng National Forest Park, Beijing, China. Material and methods: The flow patterns were measured by field dye tracing experiments. Different species (Sophora japonica Linn,Platycladus orientalis Franco, Quercus dentata Thunbwere quantified in two replicates, and 12 soil depth were applied. Plant roots were sampled in the sieving methods. Root length density and root biomass were measured by WinRHIZO. Dye coverage was implied in the image analysis, and maximum depth of dye infiltration by direct measurement. Main results: Root length density and root biomass decreased with the increasing distance from soil surface, and root length density was 81.6% higher in preferential pathways than in soil matrix, and 66.7% for root biomass with respect to all experimental plots. Plant roots were densely distributed in the upper soil layers. Dye coverage was almost 100% in the upper 5-10 cm, but then decreased rapidly with soil depth. Root length density and root biomass were different from species: Platycladus orientalis Franco > Quercus dentata Thunb > Sophora japonica Linn. Research highlights: The results indicated that fine roots systems had strong effects on soil preferential flow, particularly root channels enhancing nutrition transport across soil profiles in forest dynamics.

  18. Profile shape parameterization of JET electron temperature and density profiles

    International Nuclear Information System (INIS)

    Schunke, B.

    1997-01-01

    The temperature and density profiles of the Joint European Torus (JET) are parametrized using log additive models in the control variables. Predictive error criteria are used to determine which terms in the log linear model to include. The density and temperature profiles are normalized to their line averages (n-bar and T-bar). The normalized ohmic density shape depends primarily on the parameter n-bar/B t , where B t is the toroidal magnetic field. Both the low mode (L mode) and the edge localized mode-free (ELM-free) high mode (H mode) temperature profiles shapes depend strongly on the type of heating power, with ion cyclotron resonant heating (ICRH) producing a more peaked profile than neutral beam injection (NBI). Given the heating type dependence, the L mode temperature shape is nearly independent of the other control variables. The H mode temperature shape broadens as the effective charge, Z eff , increases. The line average L mode temperature scales as B 0.96 t (power per particle) 0.385 . The L mode normalized density shape depends primarily on the ratio of line average density, n-bar, to the edge safety factor, q 95 . As n-bar/q 95 increases, the profile shape broadens. The current, I p , is the most important control variable for the normalized H mode density. As the current increases, the profile broadens and the gradient at the edge sharpens. Increasing the heating power, especially ICRH, or decreasing the average density, peaks the H mode density profile slightly. (author). 15 refs, 12 figs, 10 tabs

  19. Edge density profiles in high-performance JET plasmas

    International Nuclear Information System (INIS)

    Summers, D.D.R.; Viaccoz, B.; Vince, J.

    1997-01-01

    Detailed electron density profiles of the scrape-off layer in high-performance JET plasmas (plasma current, I p nbi ∝17 MW) have been measured by means of a lithium beam diagnostic system featuring high spatial resolution [Kadota (1978)[. Measurements were taken over a period of several seconds, allowing examination of the evolution of the edge profile at a location upstream from the divertor target. The data clearly show the effects of the H-mode transition - an increase in density near the plasma separatrix and a reduction in density scrape-off length. The profiles obtained under various plasma conditions are compared firstly with data from other diagnostics, located elsewhere in the vessel, and also with the predictions of an 'onion-skin' model (DIVIMP), which used, as initial parameters, data from an array of probes located in the divertor target. (orig.)

  20. Length scale and manufacturability in density-based topology optimization

    DEFF Research Database (Denmark)

    Lazarov, Boyan Stefanov; Wang, Fengwen; Sigmund, Ole

    2016-01-01

    Since its original introduction in structural design, density-based topology optimization has been applied to a number of other fields such as microelectromechanical systems, photonics, acoustics and fluid mechanics. The methodology has been well accepted in industrial design processes where it can...... performance and in many cases can completely destroy the optimality of the solution. Therefore, the goal of this paper is to review recent advancements in obtaining manufacturable topology-optimized designs. The focus is on methods for imposing minimum and maximum length scales, and ensuring manufacturable...

  1. A SURVEY OF CORONAL CAVITY DENSITY PROFILES

    International Nuclear Information System (INIS)

    Fuller, J.; Gibson, S. E.

    2009-01-01

    Coronal cavities are common features of the solar corona that appear as darkened regions at the base of coronal helmet streamers in coronagraph images. Their darkened appearance indicates that they are regions of lowered density embedded within the comparatively higher density helmet streamer. Despite interfering projection effects of the surrounding helmet streamer (which we refer to as the cavity rim), Fuller et al. have shown that under certain conditions it is possible to use a Van de Hulst inversion of white-light polarized brightness (pB) data to calculate the electron density of both the cavity and cavity rim plasma. In this article, we apply minor modifications to the methods of Fuller et al. in order to improve the accuracy and versatility of the inversion process, and use the new methods to calculate density profiles for both the cavity and cavity rim in 24 cavity systems. We also examine trends in cavity morphology and how departures from the model geometry affect our density calculations. The density calculations reveal that in all 24 cases the cavity plasma has a flatter density profile than the plasma of the cavity rim, meaning that the cavity has a larger density depletion at low altitudes than it does at high altitudes. We find that the mean cavity density is over four times greater than that of a coronal hole at an altitude of 1.2 R sun and that every cavity in the sample is over twice as dense as a coronal hole at this altitude. Furthermore, we find that different cavity systems near solar maximum span a greater range in density at 1.2 R sun than do cavity systems near solar minimum, with a slight trend toward higher densities for systems nearer to solar maximum. Finally, we found no significant correlation of cavity density properties with cavity height-indeed, cavities show remarkably similar density depletions-except for the two smallest cavities that show significantly greater depletion.

  2. New description of the electron density profile

    International Nuclear Information System (INIS)

    Rawer, K.

    1984-01-01

    Several methods are described by which the entire electron density profile of the International Reference Ionosphere (IRI) could be respresented analytically while emphasizing the most important physical features. Consideration is given to the use of absolute values as a sum of individual Ne (height) functions in order to eliminate conventional time-consuming fitting procedures. It is recommended that three Epstein steps be integrated in the skeleton function, thereby providing a total of eleven parameters for the profile. Some of the parameters might be only slowly variable (HX2, HX3, SC2, SC3). 9 references

  3. The probability density function of completed length of service (CLS ...

    African Journals Online (AJOL)

    ... functions this paper estimates the functions for some secondary schools in Enugu State. Wastage probabilities are calculated, survivor functions estimated. The accompanying standard errors are also obtained. Key words: Manpower Planning, Length of Service, Modelling, Survivor Functions. [Global Jnl Mathematical Sci ...

  4. MGS RS: IONOSPHERIC ELECTRON DENSITY PROFILES V1.0

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains 5600 ionospheric electron density profiles (EDS files) derived from Mars Global Surveyor (MGS) radio occultation data. The profiles were...

  5. Radial stability of density profiles for obliquely incident light

    International Nuclear Information System (INIS)

    Powers, L.V.; Montry, G.R.; Tanner, D.J.; Berger, R.L.

    1980-01-01

    Self-consistent steady-state plasma density profiles including the effects of the ponderomotive force for obliquely incident light have been obtained for the case of supersonic upstream flow velocity. The radial stability of these density profiles is studied in one-dimensional spherical geometry. Above a modest threshold laser field, these density profiles are found to be unstable and exhibit unsteady flow. The absorption for unstable profiles is found to vary markedly in time. Radiation and plasma waves can be trapped in density troughs which may be unstable to kink or sausage instabilities in two dimensions. (author)

  6. The relationship between fission track length and track density in apatite

    International Nuclear Information System (INIS)

    Laslett, G.M.; Gleadow, A.J.W.; Duddy, I.R.

    1984-01-01

    Fission track dating is based upon an age equation derived from a random line segment model for fission tracks. This equation contains the implicit assumption of a proportional relationship between the true mean length of fission tracks and their track density in an isotropic medium. Previous experimental investigation of this relationship for both spontaneous and induced tracks in apatite during progressive annealment model in an obvious fashion. Corrected equations relating track length and density for apatite, an anisotropic mineral, show that the proportionality in this case is between track density and a length factor which is a generalization of the mean track length combining the actual length and crystallographic orientation of the track. This relationship has been experimentally confirmed for induced tracks in Durango apatite, taking into account bias in sampling of the track lengths, and the effect of the bulk etching velocity. (author)

  7. NEW CONCEPTS AND TEST METHODS OF CURVE PROFILE AREA DENSITY IN SURFACE: ESTIMATION OF AREAL DENSITY ON CURVED SPATIAL SURFACE

    OpenAIRE

    Hong Shen

    2011-01-01

    The concepts of curve profile, curve intercept, curve intercept density, curve profile area density, intersection density in containing intersection (or intersection density relied on intersection reference), curve profile intersection density in surface (or curve intercept intersection density relied on intersection of containing curve), and curve profile area density in surface (AS) were defined. AS expressed the amount of curve profile area of Y phase in the unit containing surface area, S...

  8. Lee-Yang-inspired functional with a density-dependent neutron-neutron scattering length

    Science.gov (United States)

    Grasso, M.; Lacroix, D.; Yang, C. J.

    2017-05-01

    Inspired by the low-density Lee-Yang expansion for the energy of a dilute Fermi gas of density ρ and momentum kF, we introduce here a Skyrme-type functional that contains only s -wave terms and provides, at the mean-field level, (i) a satisfactory equation of state for neutron matter from extremely low densities up to densities close to the equilibrium point, and (ii) a good-quality equation of state for symmetric matter at density scales around the saturation point. This is achieved by using a density-dependent neutron-neutron scattering length a (ρ ) which satisfies the low-density limit (for Fermi momenta going to zero) and has a density dependence tuned in such a way that the low-density constraint |a (ρ ) kF|≤1 is satisfied at all density scales.

  9. On the length-scale of the wind profile

    DEFF Research Database (Denmark)

    Pena Diaz, Alfredo; Gryning, Sven-Erik; Mann, Jakob

    2010-01-01

    We present the results of an analysis of simultaneous sonic anemometer observations of wind speed and velocity spectra over flat and homogeneous terrain from 10 up to 160 m height performed at the National Test Station for Wind Turbines at Høvsøre, Denmark. The mixing length, l, derived from the ...

  10. Modeling relaxation length and density of acacia mangium wood using gamma - ray attenuation technique

    International Nuclear Information System (INIS)

    Tamer A Tabet; Fauziah Abdul Aziz

    2009-01-01

    Wood density measurement is related to the several factors that influence wood quality. In this paper, density, relaxation length and half-thickness value of eight ages, 3, 5, 7, 10, 11, 13 and 15 year-old of Acacia mangium wood were determined using gamma radiation from 137 Cs source. Results show that Acacia mangium tree of age 3 year has the highest relaxation length of 83.33 cm and least density of 0.43 gcm -3 , while the tree of age 15 year has the least Relaxation length of 28.56 cm and highest density of 0.76 gcm -3 . Results also show that the 3 year-old Acacia mangium wood has the highest half thickness value of 57.75 cm and 15 year-old tree has the least half thickness value of 19.85 cm. Two mathematical models have been developed for the prediction of density, variation with relaxation length and half-thickness value of different age of tree. A good agreement (greater than 85% in most cases) was observed between the measured values and predicted ones. Very good linear correlation was found between measured density and the age of tree (R2 = 0.824), and between estimated density and Acacia mangium tree age (R2 = 0.952). (Author)

  11. Modification of SOL profiles and fluctuations with line-average density and divertor flux expansion in TCV

    DEFF Research Database (Denmark)

    Vianello, N.; Tsui, C.; Theiler, C.

    2017-01-01

    A set of Ohmic density ramp experiments addressing the role of parallel connection length in modifying scrape off layer (SOL) properties has been performed on the TCV tokamak. The parallel connection length has been modified by varying the poloidal flux expansion fx. It will be shown that this mo......A set of Ohmic density ramp experiments addressing the role of parallel connection length in modifying scrape off layer (SOL) properties has been performed on the TCV tokamak. The parallel connection length has been modified by varying the poloidal flux expansion fx. It will be shown...... that this modification does not influence neither the detachment density threshold, nor the development of a flat SOL density profile which instead depends strongly on the increase of the core line average density. The modification of the SOL upstream profile, with the appearance of what is generally called a density...... shoulder, has been related to the properties of filamentary blobs. Blob size increases with density, without any dependence on the parallel connection length both in the near and far SOL. The increase of the density decay length, corresponding to a profile flattening, has been related to the variation...

  12. Ion acceleration in electrostatic collisionless shock: on the optimal density profile for quasi-monoenergetic beams

    Science.gov (United States)

    Boella, E.; Fiúza, F.; Stockem Novo, A.; Fonseca, R.; Silva, L. O.

    2018-03-01

    A numerical study on ion acceleration in electrostatic shock waves is presented, with the aim of determining the best plasma configuration to achieve quasi-monoenergetic ion beams in laser-driven systems. It was recently shown that tailored near-critical density plasmas characterized by a long-scale decreasing rear density profile lead to beams with low energy spread (Fiúza et al 2012 Phys. Rev. Lett. 109 215001). In this work, a detailed parameter scan investigating different plasma scale lengths is carried out. As result, the optimal plasma spatial scale length that allows for minimizing the energy spread while ensuring a significant reflection of ions by the shock is identified. Furthermore, a new configuration where the required profile has been obtained by coupling micro layers of different densities is proposed. Results show that this new engineered approach is a valid alternative, guaranteeing a low energy spread with a higher level of controllability.

  13. A parameterization of momentum roughness length and displacement height for a wide range of canopy densities

    Directory of Open Access Journals (Sweden)

    A. Verhoef

    1997-01-01

    Full Text Available Values of the momentum roughness length, z0, and displacement height, d, derived from wind profiles and momentum flux measurements, are selected from the literature for a variety of sparse canopies. These include savannah, tiger-bush and several row crops. A quality assessment of these data, conducted using criteria such as available fetch, height of wind speed measurement and homogeneity of the experimental site, reduced the initial total of fourteen sites to eight. These datapoints, combined with values carried forward from earlier studies on the parameterization of z0 and d, led to a maximum number of 16 and 24 datapoints available for d and z0, respectively. The data are compared with estimates of roughness length and displacement height as predicted from a detailed drag partition model, R92 (Raupach, 1992, and a simplified version of this model, R94 (Raupach, 1994. A key parameter in these models is the roughness density or frontal area index, λ. Both the comprehensive and the simplified model give accurate predictions of measured z0 and d values, but the optimal model coefficients are significantly different from the ones originally proposed in R92 and R94. The original model coefficients are based predominantly on measured aerodynamic parameters of relatively closed canopies and they were fitted `by eye'. In this paper, best-fit coefficients are found from a least squares minimization using the z0 and d values of selected good-quality data for sparse canopies and for the added, mainly closed canopies. According to a statistical analysis, based on the coefficient of determination (r2, the number of observations and the number of fitted model coefficients, the simplified model, R94, is deemed to be the most appropriate for future z0 and d predictions. A CR value of 0.35 and a cd1 value of about 20 are found to be appropriate for a large range of canopies varying in density from closed to very sparse. In this case, 99% of the total variance

  14. Electron Density Profile Data Contains Virtual Height/Frequency Pairs from a Profile or Profiles (Composite Months) of Ionograms

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Electron Density Profile, N(h), data set contains both individual profiles and composite months. The data consist of virtual height/frequency pairs from a...

  15. On the neutron scattering length density of proteins in H2O/D2O

    Science.gov (United States)

    Efimova, Y. M.; van Well, A. A.; Hanefeld, U.; Wierczinski, B.; Bouwman, W. G.

    2004-07-01

    The structure of the protein layers adsorbed at different interfaces can be determined by using neutron-reflection and small-angle neutron scattering. For highlighting the adsorbed protein layer at the interface, the technique of contrast-variation by changing the H2O/D2O ratio, is often used. For determining the scattering length density, both the protein volume in solution and the total scattering length of the protein is needed. The volume is calculated from the amino-acid sequence. For calculating the scattering length, the H/D exchange of the labile protons of the protein should be taken into account. For monitoring the H/D exchange, Positive Electrospray Ionization Mass Spectroscopy was applied. We compare experimental results for the exchange in lysozyme and β-casein with theoretical calculations. The importance of using the correct protein scattering-length density is elucidated by simultaneous model fitting to neutron reflection data at different water contrasts.

  16. On the neutron scattering length density of proteins in H2O/D2O

    International Nuclear Information System (INIS)

    Efimova, Y.M.; Well, A.A. van; Hanefeld, U.; Wierczinski, B.; Bouwman, W.G.

    2004-01-01

    The structure of the protein layers adsorbed at different interfaces can be determined by using neutron-reflection and small-angle neutron scattering. For highlighting the adsorbed protein layer at the interface, the technique of contrast-variation by changing the H 2 O/D 2 O ratio, is often used. For determining the scattering length density, both the protein volume in solution and the total scattering length of the protein is needed. The volume is calculated from the amino-acid sequence. For calculating the scattering length, the H/D exchange of the labile protons of the protein should be taken into account. For monitoring the H/D exchange, Positive Electrospray Ionization Mass Spectroscopy was applied. We compare experimental results for the exchange in lysozyme and β-casein with theoretical calculations. The importance of using the correct protein scattering-length density is elucidated by simultaneous model fitting to neutron reflection data at different water contrasts

  17. Space potential, temperature, and density profile measurements on RENTOR

    International Nuclear Information System (INIS)

    Schoch, P.M.

    1983-05-01

    Radial profiles of the space potential, electron temperature, and density have been measured on RENTOR with a heavy-ion-beam probe. The potential profile has been compared to predictions from a stochastic magnetic field fluctuation theory, using the measured temperature and density profiles. The comparison shows strong qualitative agreement in that the potential is positive and the order of T/sub e//e. There is some quantitative disagreement in that the measured radial electric fields are somewhat smaller than the theoretical predictions. To facilitate this comparison, a detailed analysis of the possible errors has been completed

  18. Self-organized edge density profile with turbulent pinch

    Science.gov (United States)

    Zhu, Ben; Francisquez, Manaura; Rogers, Barrett

    2017-10-01

    In many tokamak operations, plasma is only fueled by ionization of neutrals in the periphery which subsequently penetrate inward toward core and form a peaked density profile - a process commonly referred as density pinch. Although the Ware effect, and drift wave-/ITG-/TEM-based turbulent transport theory are proposed to explain density pinch in the core region (r / a fluid edge turbulence code, GDB. GDB is a flux-driven electromagnetic model self-consistently evolving plasma density, temperature as well as the sheared flow profiles in both closed-flux surfaces and the SOL. In this study, the effective simulation domain is 0.8 < r / a < 1.1 with a heat source located at r / a < 0.8 and a Gaussian particle source located in a relatively small region near the separatrix (0.96 < r / a < 1.05). An inward (up-gradient) particle flux in the closed flux region is observed once the particle source is turned on until the system reaches quasi-steady-state with a slightly peaked density profile. The final density profile seems insensitive to particle source profiles but largely depends on the other plasma parameters, e.g., plasma temperature. This work was supported by DOE-SC-0010508. This research used resources of the National Energy Research Scientific Computing Center.

  19. Characterization of laser-produced plasma density profiles using grid image refractometry

    International Nuclear Information System (INIS)

    Craxton, R.S.; Turner, F.S.; Hoefen, R.; Darrow, C.; Gabl, E.F.; Busch, G.E.

    1993-01-01

    Grid image refractometry (GIR) is proposed as a technique for determining the two-dimensional density profiles of long scale-length laser-produced plasmas. Its distinctive feature is that an optical probe beam is broken up into ''rays'' by being passed through a grid before traversing the plasma. The refraction angles of the rays are measured by imaging the plasma at two or more object planes and are integrated to yield the phase front. For cylindrically symmetric plasmas the density profile is then determined using Abel inversion. The feasibility of GIR is illustrated by an experiment in which a thick CH target was irradiated with ∼100 J of 527 nm radiation and diagnosed with a 20 ps, 263 nm probe. The resulting density profile is substantially larger than any that have previously been reported using interferometry and compares quite closely with hydrodynamic simulations

  20. Sugarcane root length density and distribution from root intersection counting on a trench-profile Densidade de comprimento e distribuição de raízes de cana-de-açúcar a partir da contagem de intersecção de raízes na parede do perfil

    Directory of Open Access Journals (Sweden)

    Mateus Carvalho Basilio de Azevedo

    2011-02-01

    Full Text Available Root length density (RLD is a critical feature in determining crops potential to uptake water and nutrients, but it is difficult to be measured. No standard method is currently available for assessing RLD in the soil. In this study, an in situ method used for other crops for studying root length density and distribution was tested for sugarcane (Saccharum spp.. This method involved root intersection counting (RIC on a Rhodic Eutrudox profile using grids with 0.05 x 0.05 m and modeling RLD from RIC. The results were compared to a conventional soil core-sampled method (COR (volume 0.00043 m³. At four dates of the cropping season in three tillage treatments (plowing soil, minimum tillage and direct planting, with eight soil depths divided in 0.1 m soil layer (between 0-0.6 and 1.6-1.8 m and three horizontal distances from the row (0-0.23, 0.23-0.46 and 0.46-0.69 m, COR and RIC methods presented similar RLD results. A positive relationship between COR and RIC was found (R² = 0.76. The RLD profiles considering the average of the three row distances per depth obtained using COR and RIC (mean of four dates and 12 replications were close and did not differ at each depth of 0.1 m within a total depth of 0.6 m. Total RLD between 0 and 0.6 m was 7.300 and 7.100 m m-2 for COR and RIC respectively. For time consumption, the RIC method was tenfold less time-consuming than COR and RIC can be carried out in the field with no need to remove soil samples. The RLD distribution in depth and row distance (2-D variability by RIC can be assessed in relation to the soil properties in the same soil profiles. The RIC method was suitable for studying these 2-D (depth and row distance in the soil profile relationships between soil, tillage and root distribution in the field.A densidade de comprimento de raízes (DCR é uma característica importante para determinar o potencial de absorção de água e nutrientes das plantas, mas é difícil de ser medida. Nenhum m

  1. The flat density profiles of massive, and relaxed galaxy clusters

    Energy Technology Data Exchange (ETDEWEB)

    Popolo, A. Del, E-mail: adelpopolo@oact.inaf.it [Dipartimento di Fisica e Astronomia, University Of Catania, Viale Andrea Doria 6, Catania, 95125 (Italy)

    2014-07-01

    The present paper is an extension and continuation of Del Popolo (2012a) which studied the role of baryon physics on clusters of galaxies formation. In the present paper, we studied by means of the SIM introduced in Del Popolo (2009), the total and DM density profiles, and the correlations among different quantities, observed by Newman et al. (2012a,b), in seven massive and relaxed clusters, namely MS2137, A963, A383, A611, A2537, A2667, A2390. As already found in Del Popolo 2012a, the density profiles depend on baryonic fraction, angular momentum, and the angular momentum transferred from baryons to DM through dynamical friction. Similarly to Newman et al. (2012a,b), the total density profile, in the radius range 0.003–0.03r{sub 200}, has a mean total density profile in agreement with dissipationless simulations. The slope of the DM profiles of all clusters is flatter than -1. The slope, α, has a maximum value (including errors) of α = −0.88 in the case of A2390, and minimum value α = −0.14 for A2537. The baryonic component dominates the mass distribution at radii < 5–10 kpc, while the outer distribution is dark matter dominated. We found an anti-correlation among the slope α, the effective radius, R{sub e}, and the BCG mass, and a correlation among the core radius r{sub core}, and R{sub e}. Moreover, the mass in 100 kpc (mainly dark matter) is correlated with the mass inside 5 kpc (mainly baryons). The behavior of the total mass density profile, the DM density profile, and the quoted correlations can be understood in a double phase scenario. In the first dissipative phase the proto-BCG forms, and in the second dissipationless phase, dynamical friction between baryonic clumps (collapsing to the center) and the DM halo flattens the inner slope of the density profile. In simple terms, the large scatter in the inner slope from cluster to cluster, and the anti-correlation among the slope, α and R{sub e} is due to the fact that in order to have a total

  2. Influence of an axial magnetic field on the density profile of capillary plasma channels

    CERN Document Server

    Ivanov, V V; Toma, E S; Bijkerk, F

    2003-01-01

    A narrow capillary plasma channel, with a sizeable depletion of the electron density on the channel axis, has been proposed to guide a laser pulse over a length of several to several tens of centimetres. We discuss the possibility to significantly improve the wave-guiding properties of such a channel by applying an axial magnetic field. Our analytical and numerical studies show that a pulsed axial magnetic field of 10 T in a hydrogen capillary plasma at a pressure of 50 Torr will reduce the on-axis plasma density by a factor of three, and the full width at half maximum of the density profile by a factor of two. The resulting parabolic plasma density profile is expected to be more efficient in guiding laser pulses.

  3. Flame Treatment of Low-Density Polyethylene: Surface Chemistry Across the Length Scale

    NARCIS (Netherlands)

    Song, Jing; Gunst, Ullrich; Arlinghaus, Heinrich F.; Vancso, Gyula J.

    2007-01-01

    The relationship between surface chemistry and morphology of flame treated low-density polyethylene (LDPE) was studied by various characterization techniques across different length scales. The chemical composition of the surface was determined on the micrometer scale by X-ray photoelectron

  4. Compensation in Root Water Uptake Models Combined with Three-Dimensional Root Length Density Distribution

    NARCIS (Netherlands)

    Heinen, M.

    2014-01-01

    A three-dimensional root length density distribution function is introduced that made it possible to compare two empirical uptake models with a more mechanistic uptake model. Adding a compensation component to the more empirical model resulted in predictions of root water uptake distributions

  5. Use of dispersive effects for density profile reconstruction from pulse radar reflectometry measurements alone

    International Nuclear Information System (INIS)

    Hacquin, S.; Heuraux, S.; Colin, M.; Leclert, G.

    2000-01-01

    Reflectometry deduces the density profiles from the time of flight measurements for different frequencies of the probing wave. Pulse radar reflectometry allows the time of flight measurements at only a few discrete frequencies (typically 10 frequencies), which can lead to bad profile reconstruction. In order to improve the profile determination, it is proposed to use a dispersive effect of higher order, namely the pulse broadening. It is shown that usual methods of profile reconstruction are then improved. Particular attention is paid to the initialization problem, which is crucial in O-mode reflectometry. Initialization methods that use only reflectometry measurements have been developed. The sensitivity of each method to the measurement errors is discussed. Errors due to density fluctuations have been investigated numerically. For density fluctuations with moderate amplitude, the time of flight can be significantly modified whereas the pulse broadening is mostly unchanged. It is shown that, even with significant errors (10% on the time of flight, up to 40% on the pulse broadening) the profile initialization can be improved by using both time of flight and optimal length. The density profile is then reconstructed with an acceptable accuracy. (author)

  6. Ionospheric electron density profile estimation using commercial AM broadcast signals

    Science.gov (United States)

    Yu, De; Ma, Hong; Cheng, Li; Li, Yang; Zhang, Yufeng; Chen, Wenjun

    2015-08-01

    A new method for estimating the bottom electron density profile by using commercial AM broadcast signals as non-cooperative signals is presented in this paper. Without requiring any dedicated transmitters, the required input data are the measured elevation angles of signals transmitted from the known locations of broadcast stations. The input data are inverted for the QPS model parameters depicting the electron density profile of the signal's reflection area by using a probabilistic inversion technique. This method has been validated on synthesized data and used with the real data provided by an HF direction-finding system situated near the city of Wuhan. The estimated parameters obtained by the proposed method have been compared with vertical ionosonde data and have been used to locate the Shijiazhuang broadcast station. The simulation and experimental results indicate that the proposed ionospheric sounding method is feasible for obtaining useful electron density profiles.

  7. [Changes in bone mineral density of postmenopausal women in relation to the menstrual cycle length].

    Science.gov (United States)

    Enchev, E; Dimitrakova, E

    2010-01-01

    There is a strong relationship between the age of menarche, the length of the menstrual cycle and menstrual bleeding and fracture risk in the postmenopausal period. Evaluation of the menstrual cycle length and lumbar bone mineral density in postmenopausal women. We investigated three groups of postmenopausal women (each - n = 50). The first group included women with menstrual duration of 27 days during reproductive age, the second group included postmenopausal women with menstrual duration of 28 days during the reproductive age, and the third group consisted of postmenopausal women with menstrual duration of 30 days during reproductive age. The average age of women was 58.80 +/- 0.94 y. in the first group, 60.36 +/- 5.12 y. in the second group and -61.84 +/- 0.80 y. in the third group. Age, age of menarche, number of childbirths, length of the menstrual cycle and menstrual bleeding, and lumbar bone density were assessed and registered for each woman. We used DXA in a anterior-posterior projection to assess the bone density of the lumbar spine; the obtained results are shown in gram/cm2. The women from the third group, with average menstrual cycle length of 30 days, reach menopause at a significantly later age, have longer menstrual cycle and shorter menstrual bleeding, and higher lumbar spine bone density, compared to the other two groups. The data from our research show that women with anamnesis for average normal menstrual cycle length of 30 days reach menopausal period at a significantly later age, have shorter menstrual bleeding, and higher lumbar spine bone density compared to those with shorter menstrual cycle duration (27 and 28 days).

  8. Length-scale effect due to periodic variation of geometrically necessary dislocation densities

    DEFF Research Database (Denmark)

    Oztop, M. S.; Niordson, Christian Frithiof; Kysar, J. W.

    2013-01-01

    Strain gradient plasticity theories have been successful in predicting qualitative aspects of the length scale effect, most notably the increase in yield strength and hardness as the size of the deforming volume decreases. However new experimental methodologies enabled by recent developments...... the microstructure of deformed metals in addition to the size effect. Recent GND measurements have revealed a distribution of length scales that evolves within a metal undergoing plastic deformation. Furthermore, these experiments have shown an accumulation of GND densities in cell walls as well as a variation...... of the saturation value of dislocation densities in these cell walls and dislocation structures. In this study, a strain gradient plasticity framework is extended by incorporating the physical quantities obtained from experimental observations: the quasi-periodicity and the saturation value of GND densities...

  9. Charnock's Roughness Length Model and Non-dimensional Wind Profiles Over the Sea

    DEFF Research Database (Denmark)

    Pena Diaz, Alfredo; Gryning, Sven-Erik

    2008-01-01

    An analysis tool for the study of wind speed profiles over the water has been developed. The profiles are analysed using a modified dimensionless wind speed and dimensionless height, assuming that the sea surface roughness can be predicted by Charnock's roughness length model. In this form, the r...

  10. Modification of SOL profiles and fluctuations with line-average density and divertor flux expansion in TCV

    Science.gov (United States)

    Vianello, N.; Tsui, C.; Theiler, C.; Allan, S.; Boedo, J.; Labit, B.; Reimerdes, H.; Verhaegh, K.; Vijvers, W. A. J.; Walkden, N.; Costea, S.; Kovacic, J.; Ionita, C.; Naulin, V.; Nielsen, A. H.; Rasmussen, J. Juul; Schneider, B.; Schrittwieser, R.; Spolaore, M.; Carralero, D.; Madsen, J.; Lipschultz, B.; Militello, F.; The TCV Team; The EUROfusion MST1 Team

    2017-11-01

    A set of Ohmic density ramp experiments addressing the role of parallel connection length in modifying scrape off layer (SOL) properties has been performed on the TCV tokamak. The parallel connection length has been modified by varying the poloidal flux expansion f x . It will be shown that this modification does not influence neither the detachment density threshold, nor the development of a flat SOL density profile which instead depends strongly on the increase of the core line average density. The modification of the SOL upstream profile, with the appearance of what is generally called a density shoulder, has been related to the properties of filamentary blobs. Blob size increases with density, without any dependence on the parallel connection length both in the near and far SOL. The increase of the density decay length, corresponding to a profile flattening, has been related to the variation of the divertor normalized collisionality Λ_div (Myra et al 2006 Phys. Plasmas 13 112502, Carralero et al, ASDEX Upgrade Team, JET Contributors and EUROfusion MST1 Team 2015 Phys. Rev. Let. 115 215002), showing that in TCV the increase of Λ_div is not sufficient to guarantee the SOL upstream profile flattening.

  11. Effects of wall roughness and entry length on void profile in vertical bubbly flow

    International Nuclear Information System (INIS)

    Takamasa, Tomoji

    1988-01-01

    An experimental study of upward air-water bubbly two-phase flow in an entry region was performed with various rough wall test tubes. The objective of the work is to clarify the effects of wall roughness and entry length on void profile. The fluid flows in the vertical circular test tube of 25 mm I.D. under nearly atmospheric pressure, at room temperature. The void profile changes from a pattern similar in appearance to the saddle shape which has local void peaks near the wall, into the power law shape whose curve is approximated by a power law formula, with increasing wall roughness and/or entry length. That is, wall roughness and entry length have a similar effect upon void profile. There are two patterns in the power law shape, a pattern with sharp center peak and a pattern with obtuse center peak. As wall roughness and/or entry length increase, the void profile changes from the former pattern to the latter pattern. At enough long entry length (L/D ≅ 150), every void profile has almost the same power law shape independent of wall roughness. Some void profiles are asymmetric to the axis. (author)

  12. Behavior of the bottomside electron density profile over Pruhonice

    Czech Academy of Sciences Publication Activity Database

    Mosert, M.; Burešová, Dalia; Ezquer, R.; Mansilla, G.

    2004-01-01

    Roč. 34, č. 9 (2004), s. 1982-1989 ISSN 0273-1177 R&D Projects: GA AV ČR IAA3042102 Institutional research plan: CEZ:AV0Z3042911 Keywords : Electron density profiles * Variability Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 0.548, year: 2004

  13. Study of density and temperature profile across the magnetic island

    International Nuclear Information System (INIS)

    Qingquan Yu; Yuping Huo

    1991-01-01

    It is well known that the magnetic island develops near the rational surface in tokamak due to the tearing mode instability. In the magnetic island region the energy and particle diffusivity are much larger than those outside the magnetic island due to the magnetic field fluctuations and the reconnection of the magnetic field lines of force. It is therefore considered previously that the plasma density and temperature profile are flattened there. In this paper it is found that the following question exists in the previous theories. That is whether the equilibrium condition ∇p=jxB/c can be satisfied if the plasma density and temperature profile are flattened across the magnetic island. Here p is plasma pressure, p=nT, n and j are plasma and current density, T is plasma temperature, B is the equilibrium magnetic field. If the plasma density and temperature profile are flattened across the magnetic island, the equilibrium condition will not be satisfied unless the plasma current density j and the equilibrium magnetic field B become much less inside the magnetic island than those in the case of no magnetic island. (author) 7 refs

  14. Ionospheric topside models compared with experimental electron density profiles

    Directory of Open Access Journals (Sweden)

    S. M. Radicella

    2005-06-01

    Full Text Available Recently an increasing number of topside electron density profiles has been made available to the scientific community on the Internet. These data are important for ionospheric modeling purposes, since the experimental information on the electron density above the ionosphere maximum of ionization is very scarce. The present work compares NeQuick and IRI models with the topside electron density profiles available in the databases of the ISIS2, IK19 and Cosmos 1809 satellites. Experimental electron content from the F2 peak up to satellite height and electron densities at fixed heights above the peak have been compared under a wide range of different conditions. The analysis performed points out the behavior of the models and the improvements needed to be assessed to have a better reproduction of the experimental results. NeQuick topside is a modified Epstein layer, with thickness parameter determined by an empirical relation. It appears that its performance is strongly affected by this parameter, indicating the need for improvements of its formulation. IRI topside is based on Booker's approach to consider two parts with constant height gradients. It appears that this formulation leads to an overestimation of the electron density in the upper part of the profiles, and overestimation of TEC.

  15. New signal processing technique for density profile reconstruction using reflectometry

    International Nuclear Information System (INIS)

    Clairet, F.; Bottereau, C.; Ricaud, B.; Briolle, F.; Heuraux, S.

    2011-01-01

    Reflectometry profile measurement requires an accurate determination of the plasma reflected signal. Along with a good resolution and a high signal to noise ratio of the phase measurement, adequate data analysis is required. A new data processing based on time-frequency tomographic representation is used. It provides a clearer separation between multiple components and improves isolation of the relevant signals. In this paper, this data processing technique is applied to two sets of signals coming from two different reflectometer devices used on the Tore Supra tokamak. For the standard density profile reflectometry, it improves the initialization process and its reliability, providing a more accurate profile determination in the far scrape-off layer with density measurements as low as 10 16 m -1 . For a second reflectometer, which provides measurements in front of a lower hybrid launcher, this method improves the separation of the relevant plasma signal from multi-reflection processes due to the proximity of the plasma.

  16. Current density profile inside q=1 on Tore Supra

    International Nuclear Information System (INIS)

    Joffrin, E.; Desgranges, C.; Sabot, R.; Dubois, M.A.

    1995-01-01

    The Tore Supra polarimeter used to measure the poloidal field distribution is described. The current density profiles are computed in two different ways using the interferometric and polarimetric data in conjunction with the magnetic data and the location of the inversion radius determined by the soft X-ray camera. The current density inside the q=1 surface is investigated for normal and monster sawteeth. Its variation are also measured by the polarimeter and compared with that predicted by the current diffusion equation assuming complete reconnection. Finally, the safety factor profile is compared with that obtained with the striation data of the pellet ablation. The results of the evolution of the q profile during sawteeth are in good agreement with those obtained in other devices. (author) 9 refs.; 4 figs

  17. Single crystal cupric oxide nanowires: Length- and density-controlled growth and gas-sensing characteristics

    Science.gov (United States)

    Duc, Le Duy; Le, Dang Thi Thanh; Duy, Nguyen Van; Hoa, Nguyen Duc; Hieu, Nguyen Van

    2014-04-01

    Nanowire structured p-type CuO semiconductor is a promising material for gas-sensing applications because of its unique electrical and optical properties. In this study, we demonstrate the length and density controlled synthesis of single crystal CuO nanowires (CuO NWs) by a simple and convenient thermal oxidation of high-purity copper foils in ambient atmosphere. The density and length of the CuO NWs are controlled by varying the oxidation temperature and heating duration to investigate their growth mechanism. As-synthesized materials are characterized by different techniques, such as X-ray diffraction, field emission-scanning electron microscopy, and high-resolution transmission electron microscopy. The gas-sensing characteristics of the CuO NWs are tested using hydrogen and ethanol gases. The results show that the CuO NWs could potentially sense hydrogen and ethanol gases given a working temperature of 400 °C.

  18. Kernel density estimation applied to bond length, bond angle, and torsion angle distributions.

    Science.gov (United States)

    McCabe, Patrick; Korb, Oliver; Cole, Jason

    2014-05-27

    We describe the method of kernel density estimation (KDE) and apply it to molecular structure data. KDE is a quite general nonparametric statistical method suitable even for multimodal data. The method generates smooth probability density function (PDF) representations and finds application in diverse fields such as signal processing and econometrics. KDE appears to have been under-utilized as a method in molecular geometry analysis, chemo-informatics, and molecular structure optimization. The resulting probability densities have advantages over histograms and, importantly, are also suitable for gradient-based optimization. To illustrate KDE, we describe its application to chemical bond length, bond valence angle, and torsion angle distributions and show the ability of the method to model arbitrary torsion angle distributions.

  19. Axial length and cone density as assessed with adaptive optics in myopia

    Directory of Open Access Journals (Sweden)

    Supriya Dabir

    2015-01-01

    Full Text Available Aim: To assess the variations in cone mosaic in myopia and its correlation with axial length (AL. Subjects and Methods: Twenty-five healthy myopic volunteers underwent assessment of photoreceptors using adaptive optics retinal camera at 2° and 3° from the foveal center in four quadrants superior, inferior, temporal and nasal. Data was analyzed using SPSS version 17 (IBM. Multivariable regression analysis was conducted to study the relation between cone density and AL, quadrant around the fovea and eccentricity from the fovea. Results: The mean cone density was significantly lower as the eccentricity increased from 2° from the fovea to 3° (18,560 ± 5455-16,404 ± 4494/mm 2 respectively. There was also a statistically significant difference between four quadrants around the fovea. The correlation of cone density and spacing with AL showed that there was a significant inverse relation of AL with the cone density. Conclusion: In myopic patients with good visual acuity cone density around the fovea depends on the quadrant, distance from the fovea as well as the AL. The strength of the relation of AL with cone density depends on the quadrant and distance.

  20. Analytic expressions for mode conversion in a plasma with a parabolic density profile: Generalized results

    International Nuclear Information System (INIS)

    Hinkel-Lipsker, D.E.; Fried, B.D.; Morales, G.J.

    1993-01-01

    This study provides an analytic solution to the general problem of mode conversion in an unmagnetized plasma. Specifically, an electromagnetic wave of frequency ω propagating through a plasma with a parabolic density profile of scale length L p is examined. The mode conversion points are located a distance Δ 0 from the peak of the profile, where the electron plasma frequency ω p (z) matches the wave frequency ω. The corresponding reflection, transmission, and mode conversion coefficients are expressed analytically in terms of parabolic cylinder functions for all values of Δ 0 . The method of solution is based on a source approximation technique that is valid when the electromagnetic and electrostatic scale lengths are well separated. For large Δ 0 , i.e., (cL p /ω) 1/2 much-lt Δ 0 p , the appropriately scaled result [D. E. Hinkel-Lipsker et al., Phys. Fluids B 4, 559 (1992)] for a linear density profile is recovered as the parabolic cylinder functions asymptotically become Airy functions. When Δ 0 →0, the special case of conversion at the peak of the profile [D. E. Hinkel-Lipsker et al., Phys. Fluids B 4, 1772 (1992)] is obtained

  1. Atmospheric turbulence profiling with unknown power spectral density

    Science.gov (United States)

    Helin, Tapio; Kindermann, Stefan; Lehtonen, Jonatan; Ramlau, Ronny

    2018-04-01

    Adaptive optics (AO) is a technology in modern ground-based optical telescopes to compensate for the wavefront distortions caused by atmospheric turbulence. One method that allows to retrieve information about the atmosphere from telescope data is so-called SLODAR, where the atmospheric turbulence profile is estimated based on correlation data of Shack–Hartmann wavefront measurements. This approach relies on a layered Kolmogorov turbulence model. In this article, we propose a novel extension of the SLODAR concept by including a general non-Kolmogorov turbulence layer close to the ground with an unknown power spectral density. We prove that the joint estimation problem of the turbulence profile above ground simultaneously with the unknown power spectral density at the ground is ill-posed and propose three numerical reconstruction methods. We demonstrate by numerical simulations that our methods lead to substantial improvements in the turbulence profile reconstruction compared to the standard SLODAR-type approach. Also, our methods can accurately locate local perturbations in non-Kolmogorov power spectral densities.

  2. Comparing mixing-length models of the diabatic wind profile over homogeneous terrain

    DEFF Research Database (Denmark)

    Pena Diaz, Alfredo; Gryning, Sven-Erik; Hasager, Charlotte Bay

    2010-01-01

    Models of the diabatic wind profile over homogeneous terrain for the entire atmospheric boundary layer are developed using mixing-length theory and are compared to wind speed observations up to 300 m at the National Test Station for Wind Turbines at Høvsøre, Denmark. The measurements are performed...

  3. Automated Processing of ISIS Topside Ionograms into Electron Density Profiles

    Science.gov (United States)

    Reinisch, bodo W.; Huang, Xueqin; Bilitza, Dieter; Hills, H. Kent

    2004-01-01

    Modeling of the topside ionosphere has for the most part relied on just a few years of data from topside sounder satellites. The widely used Bent et al. (1972) model, for example, is based on only 50,000 Alouette 1 profiles. The International Reference Ionosphere (IRI) (Bilitza, 1990, 2001) uses an analytical description of the graphs and tables provided by Bent et al. (1972). The Alouette 1, 2 and ISIS 1, 2 topside sounder satellites of the sixties and seventies were ahead of their times in terms of the sheer volume of data obtained and in terms of the computer and software requirements for data analysis. As a result, only a small percentage of the collected topside ionograms was converted into electron density profiles. Recently, a NASA-funded data restoration project has undertaken and is continuing the process of digitizing the Alouette/ISIS ionograms from the analog 7-track tapes. Our project involves the automated processing of these digital ionograms into electron density profiles. The project accomplished a set of important goals that will have a major impact on understanding and modeling of the topside ionosphere: (1) The TOPside Ionogram Scaling and True height inversion (TOPIST) software was developed for the automated scaling and inversion of topside ionograms. (2) The TOPIST software was applied to the over 300,000 ISIS-2 topside ionograms that had been digitized in the fkamework of a separate AISRP project (PI: R.F. Benson). (3) The new TOPIST-produced database of global electron density profiles for the topside ionosphere were made publicly available through NASA s National Space Science Data Center (NSSDC) ftp archive at . (4) Earlier Alouette 1,2 and ISIS 1, 2 data sets of electron density profiles from manual scaling of selected sets of ionograms were converted fiom a highly-compressed binary format into a user-friendly ASCII format and made publicly available through nssdcftp.gsfc.nasa.gov. The new database for the topside ionosphere established

  4. Element-specific density profiles in interacting biomembrane models

    International Nuclear Information System (INIS)

    Schneck, Emanuel; Rodriguez-Loureiro, Ignacio; Bertinetti, Luca; Gochev, Georgi; Marin, Egor; Novikov, Dmitri; Konovalov, Oleg

    2017-01-01

    Surface interactions involving biomembranes, such as cell–cell interactions or membrane contacts inside cells play important roles in numerous biological processes. Structural insight into the interacting surfaces is a prerequisite to understand the interaction characteristics as well as the underlying physical mechanisms. Here, we work with simplified planar experimental models of membrane surfaces, composed of lipids and lipopolymers. Their interaction is quantified in terms of pressure–distance curves using ellipsometry at controlled dehydrating (interaction) pressures. For selected pressures, their internal structure is investigated by standing-wave x-ray fluorescence (SWXF). This technique yields specific density profiles of the chemical elements P and S belonging to lipid headgroups and polymer chains, as well as counter-ion profiles for charged surfaces. (paper)

  5. Current density profile measurements in the Proto-Cleo Torsatron

    International Nuclear Information System (INIS)

    Schaeffer, R.C.; Shohet, J.L.

    1979-10-01

    Current density profile measurements were obtained in the Proto-Cleo Torsatron (R = 40 cm, a = 5 cm, l = 3, B/sub T/ = 3 kG, anti n approx. 10 11 cm -3 , T/sub e/ approx. 20 eV) by using a small, back-to-back flat double probe. Three different operating circuits used with this probe are presented, along with experimental results, all showing good agreement. Current is seen to flow only within the separatrix, in channels which follow the magnetic surfaces as they move radially inward with time due to changing vertical magnetic flux

  6. Reflectometry techniques for density profile measurements on fusion plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Laviron, C. [Association Euratom-CEA, Centre d`Etudes de Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. de Recherches sur la Fusion Controlee; Donne, A.J.H. [Associatie Euratom-FOM, Nieuwegein (Netherlands). FOM-Instituut voor Plasmafysica; Manso, M.E. [Instituto Superior Tecnico, Lisbon (Portugal). Lab. de Quimica Organica; Sanchez, J. [EURATOM-CIEMAT for Fusion Association, Madrid (Spain)

    1996-03-01

    Reflectometry applied to the measurement of density profiles on fusion plasmas has been subject to many recent developments. After a brief reminder of the principles of reflectometry, the theoretical accuracy of reflectometry measurements is discussed. The main difficulties limiting the performance, namely the plasma fluctuations and the quality of the transmission lines, are analysed. The different techniques used for reflectometry are then presented. The present status and achievements of actual implementations of these techniques are shown, with an analysis of their respective limitations and merits, as well as foreseen developments. (author). 70 refs.

  7. Angular filter refractometry analysis using simulated annealing [An improved method for characterizing plasma density profiles using angular filter refractometry

    International Nuclear Information System (INIS)

    Angland, P.; Haberberger, D.; Ivancic, S. T.; Froula, D. H.

    2017-01-01

    Here, a new method of analysis for angular filter refractometry images was developed to characterize laser-produced, long-scale-length plasmas using an annealing algorithm to iterative converge upon a solution. Angular filter refractometry (AFR) is a novel technique used to characterize the density pro files of laser-produced, long-scale-length plasmas. A synthetic AFR image is constructed by a user-defined density profile described by eight parameters, and the algorithm systematically alters the parameters until the comparison is optimized. The optimization and statistical uncertainty calculation is based on a minimization of the χ2 test statistic. The algorithm was successfully applied to experimental data of plasma expanding from a flat, laser-irradiated target, resulting in average uncertainty in the density profile of 5-10% in the region of interest.

  8. Electron Profile Stiffness and Critical Gradient Length Studies in the Alcator C-Mod Tokamak

    Science.gov (United States)

    Houshmandyar, Saeid; Hatch, David R.; Liao, Kenneth T.; Zhao, Bingzhe; Phillips, Perry E.; Rowan, William L.; Cao, Norman; Ernst, Darin R.; Rice, John E.

    2017-10-01

    Electron temperature profile stiffness was investigated at Alcator C-Mod L-mode discharges. Electrons were heated by ion cyclotron range of frequencies (ICRF) through minority heating. The intent of the heating mechanism was to vary the heat flux and simultaneously, gradually change the local gradient. The electron temperature gradient scale length (LTe- 1 = | ∇Te |/Te) was accurately measured through a novel technique, using the high-resolution radiometer ECE diagnostic. The TRANSP power balance analysis (Q/QGB) and the measured scale length (a/LTe) result in critical scale length measurements at all major radius locations. These measurements suggest that the profiles are already at the critical values. Furthermore, the dependence of the stiffness on plasma rotation and magnetic shear will be discussed. In order to understand the underlying mechanism of turbulence for these discharges, simulations using the gyrokinetic code, GENE, were carried out. For linear runs at electron scales, it was found that the largest growth rates are very sensitive to a/LTe variation, which suggests the presence of ETG modes, while the sensitivity studies in the ion scales indicate ITG/TEM modes. Supported by USDoE awards DE-FG03-96ER54373 and DE-FC02-99ER54512.

  9. Discrimination among individuals using terminal restriction fragment length polymorphism profiling of bacteria derived from forensic evidence.

    Science.gov (United States)

    Nishi, Eiji; Tashiro, Yukihiro; Sakai, Kenji

    2015-05-01

    DNA typing from forensic evidence is commonly used to identify individuals. However, when the quantity of the forensic evidence is insufficient, successful identification using DNA typing is impossible. Such evidence may also contain DNA from bacteria that occur naturally on the skin. In this study, we aimed to establish a profiling method using terminal restriction fragment length polymorphisms (T-RFLPs) of the amplified bacterial 16S ribosomal RNA (rRNA) gene. First, the extraction and digestion processes were investigated, and the T-RFLP profiling method using the 16S rRNA gene amplicon was optimized. We then used this method to compare the profiles of bacterial flora from the hands of 12 different individuals. We found that the T-RFLP profiles from one person on different days displayed higher similarity than those between individuals. In a principal component analysis (PCA), T-RFLPs from each individual were closely clustered in 11 out of 12 cases. The clusters could be distinguished from each other, even when the samples were collected from different conditions. No major change of the profile was observed after six months except in two cases. When handprints on glass plates were compared, 11 of 12 individuals were assigned to a few clusters including the cluster corresponding to the correct individual. In conclusion, a method for reproducible T-RFLP profiling of bacteria from trace amounts of handprints was established. The profiles were obtained for particular individuals clustered in PCA and were experimentally separable from other individuals in most cases. This technique could provide useful information for narrowing down a suspect in a criminal investigation.

  10. Effects of density profile of MDF on stiffness and strength of nailed joints

    OpenAIRE

    Sawata, Kei; Shibusawa, Tatsuya; Ohashi, Kazuo; Sotomayor Castellanos, Javier Ramon; Hatano, Yasunori

    2008-01-01

    Nail-head pull-through, lateral nail resistance, and single shear nailed joint tests were conducted on medium density fiberboard (MDF) with different density profiles, and the relations between the results of these tests and the density profiles of MDF were investigated. The maximum load of nail-head pull-through and the maximum load of nailed joints were little affected by the density profile. However, the ultimate strength of lateral nail resistance, the stiffness, and the yield strength of...

  11. Surface density profile and surface tension of the one-component classical plasma

    International Nuclear Information System (INIS)

    Ballone, P.; Senatore, G.; Trieste Univ.; Tosi, M.P.; Oxford Univ.

    1982-08-01

    The density profile and the interfacial tension of two classical plasmas in equilibrium at different densities are evaluated in the square-density-gradient approximation. For equilibrium in the absence of applied external voltage, the profile is oscillatory in the higher-density plasma and the interfacial tension is positive. The amplitude and phase of these oscillations and the magnitude of the interfacial tension are related to the width of the background profile. Approximate representations of the equilibrium profile by matching of its asymptotic forms are analyzed. A comparison with computer simulation data and a critical discussion of a local-density theory are also presented. (author)

  12. CO2 laser diagnostics for measurements of the plasma density profile and plasma density fluctuations on LHD

    International Nuclear Information System (INIS)

    Vyacheslavov, L.N.; Tanaka, K.; Kawahata, K.

    2001-04-01

    A CO 2 laser based diagnostics complimentary to the existing FIR interferometer is proposed. It combines interferometry for plasma density profile measurement under conditions of large density gradients, and both imaging and scattering techniques for observation of plasma fluctuations. Two-colour interferometer with a slablike probe beam and a single multichannel linear detector array provide observation of plasma density profile and density fluctuations at two locations along the probe beam. Basic characteristics of the diagnostics are considered as well as some effects that include dispersion and are critical for two colour imaging technique. The results of the bench-top experiments with the prototype of the interferometer are presented. (author)

  13. Localization and density of phoretic deutonymphs of the mite Uropoda orbicularis (Parasitiformes: Mesostigmata) on Aphodius beetles (Aphodiidae) affect pedicel length

    Science.gov (United States)

    Bajerlein, Daria; Witaliński, Wojciech

    2014-04-01

    The phoretic stage of Uropodina mites is a deutonymph with developed morphological adaptations for dispersal by insects. Phoretic deutonymphs are able to produce a pedicel, a stalk-like temporary attachment structure that connects the mite with the carrier. The aim of our study was to determine whether localization and density of phoretic deutonymphs on the carrier affect pedicel length. The study was conducted on a common phoretic mite— Uropoda orbicularis (Uropodina) and two aphodiid beetles— Aphodius prodromus and Aphodius distinctus. Our results show that pedicel length is influenced by the localization of deutonymphs on the body of the carrier. The longest pedicels are produced by deutonymphs attached to the upper part of elytra, whereas deutonymphs attached to femora and trochanters of the third pair of legs and the apex of elytra construct the shortest pedicels. In general, deutonymphs attached to more exposed parts of the carrier produce longer pedicels, whereas shorter pedicels are produced when deutonymphs are fixed to non-exposed parts of the carrier. A second factor influencing pedicel length is the density of attached deutonymphs. Mean pedicel length and deutonymph densities were highly correlated: higher deutonymph density leads to the formation of longer pedicels. The cause for this correlation is discussed, and we conclude that pedicel length variability can increase successful dispersal.

  14. Electron number density profiles derived from radio occultation on the CASSIOPE spacecraft

    DEFF Research Database (Denmark)

    Shume, E. B.; Vergados, P.; Komjathy, A.

    2017-01-01

    This paper presents electron number density profiles derived from high resolution Global Positioning System (GPS) radio occultation (RO) observations performed using the Enhanced Polar Outflow Probe (e-POP) payload on the high inclination CAScade, Smallsat and IOnospheric Polar Explorer (CASSIOPE......) spacecraft. We have developed and applied a novel inverse Abel transform algorithm on high rate RO total electron content (TEC) measurements performed along GPS to CASSIOPE radio links to recover electron density profiles. The high resolution density profiles inferred from the CASSIOPE RO are: (1) in very...... number density profiles retrieved over landmasses and oceans. The density profiles over oceans exhibit wide-spread values and scale heights compared to density profiles over landmasses. We provide an explanation for the ocean-landmass discrepancy in terms of the unique wave coupling mechanisms operating...

  15. Effects of the Length of Jet Grouted Columns and Soil Profile on the Settlement of Shallow Foundations

    Directory of Open Access Journals (Sweden)

    Zaheer Ahmed Almani

    2012-07-01

    Full Text Available In this paper, the effect of length of jet grouted columns and varying soil profile under shallow foundations of buildings constructed on the liquefiable ground was studied. The isolated shallow footing pad which supports a typical simple frame structure was constructed on the liquefiable ground. This ground was reinforced with jet grouted column rows under the shallow foundations of structure. The system was modeled as plane-strain using the FLAC 2D (Fast Lagrangian Analysis of Continua dynamic modelling and analysis code. This case focuses on the length of jet grouted columns in a soil profile and the effect of soil profiles of varying thickness on the settlements of building structure when the soil is liquefied during an earthquake. The results show that liquefaction-induced large settlements of shallow foundation of building decrease to tolerable limits with the increase in the length of columns. For soil profiles, with a relatively thinner liquefiable layer, a certain minimum length of columns (extended in base non liquefiable layer is required to meet the settlement tolerable limits. For soil profiles, with a relatively thicker liquefiable layer, this length should be equal to the thickness of the liquefiable layer from the footing base plus some extension in the base non liquefiable dense layer. In the soil profile with the base liquefiable layer underlying the non liquefiable layer, settlements could not be reduced to the tolerable limits even with columns of relatively larger length which may be critical.

  16. Size distribution and radial density profile of synaptic vesicles by SAXS and light scattering

    Energy Technology Data Exchange (ETDEWEB)

    Castorph, Simon; Salditt, Tim [Institute for X-ray Physics, Goettingen (Germany); Holt, Matthew; Jahn, Reinhard [Max Plank Institute for Biophysical Chemistry, Goettingen (Germany); Sztucki, Michael [European Synchrotron Radiation Facility, Grenoble (France)

    2008-07-01

    Synaptic vesicles are small membraneous organelles within the nerve terminal, encapsulating neurotransmitters by a lipid bilayer. The transport of the neurotransmitter, the fusion at the plasma membrane, and the release of the stored neurotransmitters into the synaptic cleft are since long know as essential step in nerve conduction of the chemical synapse. A detailed structural view of these molecular mechanisms is still lacking, not withstanding the enormous progress in the field during recent years. From measurements and quantitative fitting of small angle X-ray scattering curves and dynamic light scattering the averaged structural properties of synaptic vesicles can be determined. We present SAXS measurements and fits revealing the width of the size distribution function and details of the radial scattering length profile of synaptic vesicles from rat brain. Representative values for the inner and outer radius and the size polydispersity as well as the density and width of the outer protein layer are obtained.

  17. RELATIONSHIPS BETWEEN ANATOMICAL FEATURES AND INTRA-RING WOOD DENSITY PROFILES IN Gmelina arborea APPLYING X-RAY DENSITOMETRY

    Directory of Open Access Journals (Sweden)

    Mario Tomazelo-Filho

    2007-12-01

    Full Text Available Four annual tree-rings (2 of juvenile wood and 2 of mature wood were sampled from fast-growth plantations ofGmelina arborea in two climatic conditions (dry and wet tropical in Costa Rica. Each annual tree-ring was divided in equal parts ina radial direction. For each part, X-ray density as well as vessel percentage, length and width fiber, cell wall thickness and lumendiameter were measured. Wood density and profile patterns of cell dimension demonstrated inconsistency between juvenile andmature wood and climatic conditions. The Pearson correlation matrix showed that intra-ring wood density was positively correlatedwith the cell wall thickness and negatively correlated with vessel percentage, fiber length, lumen diameter and width. The forwardstepwise regressions determined that: (i intra-ring wood density variation could be predicted from 76 to 96% for anatomicalvariation; (ii cell wall thickness was the most important anatomical feature to produce intra-ring wood density variation and (iii thevessel percentage, fiber length, lumen diameter and width were the second most statically significant characteristics to intra-ring wooddensity, however, with low participation of the determination coefficient of stepwise regressions.

  18. Metastable atom probe for measuring electron beam density profiles

    Science.gov (United States)

    Lockhart, J. M.; Zorn, J. C.

    1972-01-01

    Metastable atom probe was developed for measuring current density in electron beam as function of two arbitrary coordinates, with spatial resolution better than 0.5 mm. Probe shows effects of space charge, magnetic fields, and other factors which influence electron current density, but operates with such low beam densities that introduced perturbation is very small.

  19. Dental plaque microcosm response to bonding agents containing quaternary ammonium methacrylates with different chain lengths and charge densities.

    Science.gov (United States)

    Zhou, Han; Li, Fang; Weir, Michael D; Xu, Hockin H K

    2013-11-01

    Antibacterial bonding agents are promising to combat bacteria and caries at tooth-restoration margins. The objectives of this study were to incorporate new quaternary ammonium methacrylates (QAMs) to bonding agent and determine the effects of alkyl chain length (CL) and quaternary amine charge density on dental plaque microcosm bacteria response for the first time. Six QAMs were synthesized with CL=3, 6, 9, 12, 16, 18. Each QAM was incorporated into Scotchbond multi-purpose (SBMP). To determine the charge density effect, dimethylaminododecyl methacrylate (DMAHDM, CL=16) was mixed into SBMP at mass fraction=0%, 2.5%, 5%, 7.5%, 10%. Charge density was measured using a fluorescein dye method. Dental plaque microcosm using saliva from ten donors was tested. Bacteria were inoculated on resins. Early-attachment was tested at 4h. Biofilm colony-forming units (CFU) were measured at 2 days. Incorporating QAMs into SBMP reduced bacteria early-attachment. Microcosm biofilm CFU for CL=16 was 4 log lower than SBMP control. Charge density of bonding agent increased with DMAHDM content. Bacteria early-attachment decreased with increasing charge density. Biofilm CFU at 10% DMAHDM was reduced by 4 log. The killing effect was similarly-strong against total microorganisms, total streptococci, and mutans streptococci. Increasing alkyl chain length and charge density of bonding agent was shown for the first time to decrease microcosm bacteria attachment and reduce biofilm CFU by 4 orders of magnitude. Novel antibacterial resins with tailored chain length and charge density are promising for wide applications in bonding, cements, sealants and composites to inhibit biofilms and caries. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Dental plaque microcosm response to bonding agents containing quaternary ammonium methacrylates with different chain lengths and charge densities

    Science.gov (United States)

    Zhou, Han; Li, Fang; Weir, Michael D.; Xu, Hockin H.K.

    2013-01-01

    Objectives Antibacterial bonding agents are promising to combat bacteria and caries at tooth-restoration margins. The objectives of this study were to incorporate new quaternary ammonium methacrylates (QAMs) to bonding agent and determine the effects of alkyl chain length (CL) and quaternary amine charge density on dental plaque microcosm bacteria response for the first time. Methods Six QAMs were synthesized with CL = 3, 6, 9, 12, 16, 18. Each QAM was incorporated into Scotchbond Multi-purpose (SBMP). To determine the charge density effect, dimethylaminododecyl methacrylate (DMAHDM, CL = 16) was mixed into SBMP at mass fraction = 0%, 2.5%, 5%, 7.5%, 10%. Charge density was measured using a fluorescein dye method. Dental plaque microcosm using saliva from ten donors was tested. Bacteria were inoculated on resins. Early-attachment was tested at 4 hours. Biofilm colony-forming units (CFU) were measured at 2 days. Results Incorporating QAMs into SBMP reduced bacteria early-attachment. Microcosm biofilm CFU for CL = 16 was 4 log lower than SBMP control. Charge density of bonding agent increased with DMAHDM content. Bacteria early-attachment decreased with increasing charge density. Biofilm CFU at 10% DMAHDM was reduced by 4 log. The killing effect was similarly-strong against total microorganisms, total streptococci, and mutans streptococci. Conclusions Increasing alkyl chain length and charge density of bonding agent was shown for the first time to decrease microcosm bacteria attachment and reduce biofilm CFU by 4 orders of magnitude. Novel antibacterial resins with tailored chain length and charge density are promising for wide applications in bonding, cements, sealants and composites to inhibit biofilms and caries. PMID:23948394

  1. Modeling root length density of field grown potatoes under different irrigation strategies and soil textures using artificial neural networks

    DEFF Research Database (Denmark)

    Ahmadi, Seyed Hamid; Sepaskhah, Ali Reza; Andersen, Mathias Neumann

    2014-01-01

    Root length density (RLD) is a highly wanted parameter for use in crop growth modeling but difficult to measure under field conditions. Therefore, artificial neural networks (ANNs) were implemented to predict the RLD of field grown potatoes that were subject to three irrigation strategies and three...... soil textures with different soil water status and soil densities. The objectives of the study were to test whether soil textural information, soil water status, and soil density might be used by ANN to simulate RLD at harvest. In the study 63 data pairs were divided into data sets of training (80......) of the eight input variables: soil layer intervals (D), percentages of sand (Sa), silt (Si), and clay (Cl), bulk density of soil layers (Bd), weighted soil moisture deficit during the irrigation strategies period (SMD), geometric mean particle size diameter (dg), and geometric standard deviation (σg...

  2. Momentum densities and Compton profiles of alkali-metal atoms

    Indian Academy of Sciences (India)

    Home; Journals; Pramana – Journal of Physics; Volume 60; Issue 3 ... Quantum defect theory; wave functions of alkali-metal atoms; momentum properties. ... to study the momentum properties of atoms from 3Li to 37Rb. The numerical results obtained for the momentum density, moments of momentum density and Compton ...

  3. [Profile of human milk bank donors and relationship with the length of the donation].

    Science.gov (United States)

    Sierra Colomina, G; García Lara, N; Escuder Vieco, D; Vázquez Román, S; Cabañes Alonso, E; Pallás Alonso, C R

    2014-04-01

    The promotion of Human Milk Banks is an important social service. The Human Milk Banks depend on donors, and knowing the profile of donors seems quite important. To study the demographics and lifestyles of the donors, the reasons or influences for donating, and to associate these variables with the length of the donation. This is a descriptive, cross-sectional study conducted on 168 mothers who answered the written questionnaire when they agreed to become donors. 98 (58%) responded to the telephone interview. The mean age was 33.1 ± 4.5 years. Of the total 27.9% lived outside Madrid and 21.4% were immigrants, with 23.7% working full time, 65.3% had a university education, and 96.2% had a stable partner. The main reasons for donating were too much milk (77%), and to help others (75%). The main obstacle was transportation to the Human Milk Bank for 20% of the donors, and for 61% the main reason for terminating donation was due to reaching the end of lactation. A longer donation is associated with: having a term newborn, with birth weight over 1500 g, starting donating early and reconciling the donation to the work situation. The most common donor profile was a young woman, with university education and a stable partner. Having a term new born, starting donating early, and the conciliation with work is associated with longer donations. Milk pick-up at home would make donation easier. Copyright © 2013 Asociación Española de Pediatría. Published by Elsevier Espana. All rights reserved.

  4. Cardiovascular profile in critically ill elderly medical patients: prevalence, mortality and length of stay.

    Science.gov (United States)

    Puchades, Ramón; González, Begoña; Contreras, Mar; Gullón, Alejandra; de Miguel, Rosa; Martín, Daniel; Gutiérrez, Carlos; Navarro, Ricardo

    2015-01-01

    Data are demonstrating the increase in utilization of critical care by the elderly. Around 11% of ICU patients are ≥80years-old. An observational retrospective study was conducted between 2003 and 2011, including elderly patients (≥80years old) admitted from medical services to the intensive care unit (ICU) in a tertiary university hospital. The final sample size was N=202. Mortality rates were: ICU 34.1%, in-hospital 44% and 1-year cumulative mortality 55.4% (20.4% for hospital survivors). Multivariate analysis showed that APACHE II score: OR 1.10, 95% CI (1.03-1.18), SAPS II score: OR 1.03, 95% CI (1.01-1.06), a score Cruz Roja Hospital mental scale: 0.51 OR, 95% CI (0.01-0.57) and ICU admission for cardiovascular disease: OR 5.05, 95% CI (1.98-12.84) were independently associated with mortality ICU. Factors independently associated with 1-year mortality were: dyslipidemia OR 7.25 (1.47-35.60), chronic kidney failure OR 13.23, 95% CI (2.28-76.6), stroke OR 10.44, 95% CI (2.26-48.25) and antihypertensive treatment OR 0.08, 95% CI (0.01-0.48). In multiple linear regression, ICU length of stay was associated with mechanical ventilation B coefficient 6.41, 95% CI (1.18-11.64) and in-hospital length of stay was related to age: B coefficient -2.17, 95% CI (-4.02 to -0.33). Prevalence of cardiovascular risk factors and cardiovascular disease was high, and basal cardiovascular treatment was underused. Primary diagnosis for cardiovascular disease at ICU admission should be assessed as predictor of ICU mortality. Intensifying cardiovascular basal treatment could decrease 1-year mortality. Cardiovascular profile did not show an effect on in-hospital mortality and length of stay. Copyright © 2014 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

  5. An analytical calculation of the axial density profile for 1-d slab expansion

    International Nuclear Information System (INIS)

    Ho, D

    1999-01-01

    Obtaining an analytical expression for the axial density profile can provide us with a quick and convenient way to evaluate the density evolution for targets with different densities and dimensions. In this note, we show that such an analytical expression can be obtained based on the self-similar solutions and the method of characteristics for 1-D slab expansion

  6. PEG spacers of different length influence the biological profile of bombesin-based radiolabeled antagonists

    International Nuclear Information System (INIS)

    Jamous, Mazen; Tamma, Maria L.; Gourni, Eleni; Waser, Beatrice; Reubi, Jean C.; Maecke, Helmut R.; Mansi, Rosalba

    2014-01-01

    Introduction: The gastrin-releasing peptide receptor (GRPR) was shown to be expressed with high density on several types of cancers. Radiolabeled peptides for imaging and targeted radionuclide therapy have been developed. In this study, we evaluated the potential of statine-based bombesin antagonists, conjugated to 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) through oligoethyleneglycol spacers, labeled with 177 Lu and we determined the effect of polyethyleneglycol (PEG) spacer length on in vitro and in vivo properties. Methods: The bombesin antagonists were synthesized on solid phase using Fmoc chemistry; the spacers Fmoc-dPEG x -OH (x = 2, 4, 6 and 12) and the DOTA(tBu) 3 were coupled using a standard procedure. The peptides were labeled with 177 Lu and evaluated in vitro (lipophilicity, serum stability, internalization and binding affinity assays). Biodistribution studies were performed in PC-3 tumor-bearing nude mice. Results: The solid-phase synthesis was straightforward with an overall yield ranging from 30% to 35% based on the first Fmoc cleavage. The hydrophilicity increased with spacer length (logD: − 1.95 vs − 2.22 of PEG 2 and PEG 12 analogs, respectively). There is a tendency of increased serum stability by increasing the spacer length (T 1/2 = 246 ± 4 and 584 ± 20 for PEG 2 and PEG 6 analogs, respectively) which seems to reverse with the PEG 12 analog. The IC 50 values are similar with the only significant difference of the PEG 12 analog. The 177 Lu-labeled PEG 4 and PEG 6 conjugates showed similar pharmacokinetic with high tumor uptake and excellent tumor-to-kidney ratios (7.8 and 9.7 at 4 h for the PEG 4 and PEG 6 derivatives, respectively). The pancreas uptake was relatively high at 1 h but it shows fast washout (0.46% ± 0.02% IA/g and 0.29% ± 0.08% IA/g already at 4 h). Conclusion: Among all the studied analogs the PEG 4 and PEG 6 showed significantly better properties. The very high tumor-to-non-target organ ratios, in

  7. The distribution of fine root length density for six artificial afforestation tree species in Loess Plateau of Northwest China

    Directory of Open Access Journals (Sweden)

    Shengqi Jian

    2015-04-01

    Full Text Available Aim of the study: Data about the distribution of fine root length density (FRLD is important to understand the ecophysiology of vegetation. This is particularly true when models are applied to describe ecohydrology and vegetation function. However, there is yet limited knowledge of root distributions in semi-arid regions. The aim of this study is to investigate the distribution of fine roots for six typical afforestation tree species in Loess Plateau and its relationships with soil environmental factors. Area of study: Loess Plateau (NW of China. Material and methods: We quantified the fine root length density distribution of six typical afforestation tree species by soil core method, and the soil properties also were investigated. Main results: More than 50% of fine root length was concentrated at depths between 0 and 40 cm in vertical direction. In horizontal direction, most of fine roots concentrated near the trunk. Results showed a significant negative correlation between vertical distribution of FRLD and soil water content, a positive correlation between FRLD and organic matter and total N is significant, and a negative correlation with bulk density. No relationships were found with total C and particle size distribution in any soil layer for the six tree species. Stepwise multiple linear regression confirmed that changes in different soil properties significantly affected the variation in FRLD for each tree species, total N had strong and positive relationships with FRLD. Research highlights: These measurements provide valuable data for modelling of ecosystem water use and productivity.

  8. Data description and quality assessment of ionospheric electron density profiles for ARPA modeling project. Technical report

    International Nuclear Information System (INIS)

    Conkright, R.O.

    1977-03-01

    This report presents a description of the automated method used to produce electron density (N(h)) profiles from ionograms recorded on 35mm film and an assessment of the resulting data base. A large data base of about 30,000 profiles was required for an ionospheric modeling project. This motivated a search for an automated method of producing profiles. The automated method used is fully described, the resulting data are given a quality grade, and the noon and midnight profiles are presented. Selected portions of this data base are compared with profiles produced by the standard profiling method in use by the Environmental Data Service at Boulder, Colorado

  9. Effects of cloud-point grafting, chain length, and density of PEG layers on competitive adsorption of ocular proteins

    DEFF Research Database (Denmark)

    Kingshott, P.; Thissen, H.; Griesser, H.J.

    2002-01-01

    The effects of pinning density, chain length, and 'cloud point' (CP) versus non-CP grafting conditions have been studied on the ability of polyethylene glycol (PEG) layers to minimize adsorption from a multicomponent (lysozyme, human serum albumin (HSA), IgG and lactoferrin) protein solution......-ray photoelectron spectroscopy (XPS) showed that under these conditions, PEG(ald)(2) produced a thick linear PEG layer, most likely by aldol condensation. Protein adsorption was assessed using XPS and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-ToF-MS) in the surface mode...... density) r.f.g.d. polymer layers. The PEG graft density was varied also by increasing the temperature and salt (K2SO4) content of the grafting solution; it reached a maximum at the CP of the PEGs. The CP reaction conditions were critical for producing PEG layers capable of minimizing protein adsorption. X...

  10. Using tomography of GPS TEC to routinely determine ionospheric average electron density profiles

    Science.gov (United States)

    Yizengaw, E.; Moldwin, M. B.; Dyson, P. L.; Essex, E. A.

    2007-03-01

    This paper introduces a technique that calculates average electron density (Ne) profiles over a wide geographic area of coverage, using tomographic ionospheric Ne profiles. These Ne profiles, which can provide information of the Ne distribution up to global positioning system (GPS) orbiting altitude (with the coordination of space-based GPS tomographic profiles), can be incorporated into the next generation of the international reference ionosphere (IRI) model. An additional advantage of tomography is that it enables accurate modeling of the topside ionosphere. By applying the tomographic reconstruction approach to ground-based GPS slant total electron content (STEC), we calculate 3-h average Ne profiles over a wide region. Since it uses real measurement data, tomographic average Ne profiles describe the ionosphere during quiet and disturbed periods. The computed average Ne profiles are compared with IRI model profiles and average Ne profiles obtained from ground-based ionosondes.

  11. Dependence of the outer density profiles of halos on their mass accretion rate

    International Nuclear Information System (INIS)

    Diemer, Benedikt; Kravtsov, Andrey V.

    2014-01-01

    We present a systematic study of the density profiles of ΛCDM halos, focusing on the outer regions, 0.1 < r/R vir < 9. We show that the median and mean profiles of halo samples of a given peak height exhibit significant deviations from the universal analytic profiles discussed previously in the literature, such as the Navarro-Frenk-White and Einasto profiles, at radii r ≳ 0.5R 200m . In particular, at these radii the logarithmic slope of the median density profiles of massive or rapidly accreting halos steepens more sharply than predicted. The steepest slope of the profiles occurs at r ≈ R 200m , and its absolute value increases with increasing peak height or mass accretion rate, reaching slopes of –4 and steeper. Importantly, we find that the outermost density profiles at r ≳ R 200m are remarkably self-similar when radii are rescaled by R 200m . This self-similarity indicates that radii defined with respect to the mean density are preferred for describing the structure and evolution of the outer profiles. However, the inner density profiles are most self-similar when radii are rescaled by R 200c . We propose a new fitting formula that describes the median and mean profiles of halo samples selected by their peak height or mass accretion rate with accuracy ≲ 10% at all radii, redshifts, and masses we studied, r ≲ 9R vir , 0 < z < 6, and M vir > 1.7 × 10 10 h –1 M ☉ . We discuss observational signatures of the profile features described above and show that the steepening of the outer profile should be detectable in future weak-lensing analyses of massive clusters. Such observations could be used to estimate the mass accretion rate of cluster halos.

  12. CASSINI RSS: IONOSPHERIC ELECTRON DENSITY PROFILES EDP1 V1.0

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains the complete collection of the published Cassini radio occultation electron density profiles of the Titan ionosphere as of September 2008.

  13. Age-dependence of relative telomere length profiles during spermatogenesis in man

    DEFF Research Database (Denmark)

    Jørgensen, Pernille Bach; Fedder, Jens; Koelvraa, Steen

    2013-01-01

    by telomere QFISH. Our data revealed no difference in the TL profile during spermatogenesis between younger and older men. All men had a similar profile which strongly resembled the telomerase expression profile found by others. This indicates that the longer telomeres in older men are not caused by a wider...

  14. Comparison of neutral density profiles measured using Dα and C5+ in NSTX-U

    Science.gov (United States)

    Bell, R. E.; Scotti, F.; Diallo, A.; Leblanc, B. P.; Podesta, M.; Sabbagh, S. A.

    2017-10-01

    Edge neutral density profiles determined from two different measurements are compared on NSTX-U plasmas. Neutral density measurements were not typical on NSTX plasmas. An array of fibers dedicated to the measurement of passive emission of C5+, used to subtract background emission for charge exchange recombination spectroscopy (CHERS), can be used to infer deuterium neutral density near the plasma edge. The line emission from C5+ is dominated by charge exchange with neutral deuterium near the plasma edge. An edge neutral density diagnostic consisting of a camera with a Dα filter was installed on NSTX-U. The line-integrated measurements from both diagnostics are inverted to obtain local emissivity profiles. Neutral density is then inferred using atomics rates from ADAS and profile measurements from Thomson scattering and CHERS. Comparing neutral density profiles from the two diagnostic measurements helps determine the utility of using the more routinely available C5+ measurements for neutral density profiles. Initial comparisons show good agreement between the two measurements inside the separatrix. Supported by US DoE Contracts DE-AC02-09CH11466 and DE-AC52-07NA27344.

  15. Direct calculation of optimized laser power density profiles for laser heating

    NARCIS (Netherlands)

    Römer, Gerardus Richardus, Bernardus, Engelina; de Graaf, R.F.

    2000-01-01

    Laser surface heating requires a well defined temperature profile. In this paper the inverse problem of heat conduction in solids is solved, based on the two-dimensional Fourier transform. That is, the required power density profile of the laser beam can be calculated directly from a desired

  16. Role of substituents on the reactivity and electron density profile of ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Chemical Sciences; Volume 125; Issue 5. Role of substituents on the reactivity and electron density profile of diimine ligands: A density functional theory based study. Bhakti S Kulkarni Deepti Mishra Sourav Pal. Volume 125 Issue 5 September 2013 pp 1247-1258 ...

  17. A high-density genetic map of cucumber derived from Specific Length Amplified Fragment sequencing (SLAF-seq).

    Science.gov (United States)

    Xu, Xuewen; Xu, Ruixue; Zhu, Biyun; Yu, Ting; Qu, Wenqin; Lu, Lu; Xu, Qiang; Qi, Xiaohua; Chen, Xuehao

    2014-01-01

    High-density genetic map provides an essential framework for accurate and efficient genome assembly and QTL fine mapping. Construction of high-density genetic maps appears more feasible since the advent of next-generation sequencing (NGS), which eases SNP discovery and high-throughput genotyping of large population. In this research, a high-density genetic map of cucumber (Cucumis sativus L.) was successfully constructed across an F2 population by a recently developed Specific Length Amplified Fragment sequencing (SLAF-seq) method. In total, 18.69 GB of data containing 93,460,000 paired-end reads were obtained after preprocessing. The average sequencing depth was 44.92 in the D8 (female parent), 42.16 in the Jin5-508 (male parent), and 5.01 in each progeny. 79,092 high-quality SLAFs were detected, of which 6784 SLAFs were polymorphic, and 1892 of the polymorphic markers met the requirements for constructing genetic map. The genetic map spanned 845.87 cm with an average genetic distance of 0.45 cm. It is a reliable linkage map for fine mapping and molecular breeding of cucumber for its high marker density and well-ordered markers.

  18. Influence of shrub cover vegetal and slope length on soil bulk density

    International Nuclear Information System (INIS)

    Bienes, R.; Jimenez, R.; Ruiz, M.; Garcia-Estringana, P.; Marques, M. J.

    2009-01-01

    In arid and semiarid environments of the Mediterranean climate, the shrub species play an important role in the revegetation of abandoned lands, which enables to control the soil losses, organic material and water. In this article are compared the results obtained under different revegetation in abandoned lands in the central area of Spain. In these revegetation has been used two native shrubs: A triplex halimus (Ah) and Retama sphaerocarpa (Rs), and were analyzed the influence of these revegetation in the contents of organic material of soil and apparent density in 5 years time after planting. As control, have been considered the pieces of ground with spontaneous vegetation abandoned in the same date that the shrubs revegetation. Atriplex halimus gives to the soil a covering capable to intercept a big amount of water drops absorbing a great amount part of the kinetic energy of the rain, while provides a microclimates as a result of be able to soften the wind, the temperature and the evaporation-transpiration, which makes it efficient to control the erosion and the desertification (Le Houerou, 2000). Retama sphaerocarpa was chosen because it is a native shrub very characteristic, and, due to its symbiosis with the Bradyrhizobium, enriches the soil in nitrogen, which is taken by the nitrophilous species enhancing the spontaneous vegetal covering. (Author) 9 refs.

  19. Experimental electron density profiles of the mid-latitude lower ionosphere and winter anomaly

    International Nuclear Information System (INIS)

    Rapoport, Z.Ts.; Sinel'nikov, V.M.

    1996-01-01

    Summarized measurements of high-latitude electron density profiles of N e lower ionosphere, obtained at M100B meteorological rockets by precision method of coherent frequencies during 1979-1990 at the Volgograd test site (φ = 48 deg 41' N; λ = 44 deg 21 E), are presented. The profiles obtained represent average values of electron density at various altitudes of lower ionosphere (h = 70-100 km) during night and day time hours in winter and non winter periods. Increased electron density values during daytime hours in winter are related to winter anomaly phenomenon. 36 refs.; 1 fig

  20. 2D electron density profile measurement in tokamak by laser-accelerated ion-beam probe.

    Science.gov (United States)

    Chen, Y H; Yang, X Y; Lin, C; Wang, L; Xu, M; Wang, X G; Xiao, C J

    2014-11-01

    A new concept of Heavy Ion Beam Probe (HIBP) diagnostic has been proposed, of which the key is to replace the electrostatic accelerator of traditional HIBP by a laser-driven ion accelerator. Due to the large energy spread of ions, the laser-accelerated HIBP can measure the two-dimensional (2D) electron density profile of tokamak plasma. In a preliminary simulation, a 2D density profile was reconstructed with a spatial resolution of about 2 cm, and with the error below 15% in the core region. Diagnostics of 2D density fluctuation is also discussed.

  1. Semi-analytical model of laser resonance absorption in plasmas with a parabolic density profile

    International Nuclear Information System (INIS)

    Pestehe, S J; Mohammadnejad, M

    2010-01-01

    Analytical expressions for mode conversion and resonance absorption of electromagnetic waves in inhomogeneous, unmagnetized plasmas are required for laboratory and simulation studies. Although most of the analyses of this problem have concentrated on the linear plasma density profile, there are a few research works that deal with different plasma density profiles including the parabolic profile. Almost none of them could give clear analytical formulae for the electric and magnetic components of the electromagnetic field propagating through inhomogeneous plasmas. In this paper, we have considered the resonant absorption of laser light near the critical density of plasmas with parabolic electron density profiles followed by a uniform over-dense region and have obtained expressions for the electric and magnetic vectors of laser light propagating through the plasma. An estimation of the fractional absorption of laser energy has also been carried out. It has been shown that, in contrast to the linear density profile, the energy absorption depends explicitly on the value of collision frequency as well as on a new parameter, N, called the over-dense density order.

  2. ICRF power-deposition profiles and heating in monster sawtooth and peaked-density profile discharges in JET

    International Nuclear Information System (INIS)

    Bhatnagar, V.P.; Taroni, A.; Ellis, J.J.; Jacquinot, J.; Stuart, D.F.

    1989-01-01

    In this paper, we compare experimental results of electron and ion-heating in discharges that feature monster sawtooth with those in pellet-produced peaked-density profile discharges which were heated with ICRF. Also we carry out a comprehensive analysis of ICRF-heated peaked-density profile discharges by a transport code to simulate the evolution of JET discharges and to provide an insight into the improved heating and confinement found in these discharges. In this analysis, the ICRF power-deposition profile in the minority-heating scenario is computed by the ray-tracing code BRAYCO that self-consistently takes the finite antenna geometry, its radiation spectrum and the hot-plasma damping into account. The power delivered to ions and electrons is calculated based on Stix model. (author) 10 refs., 5 figs

  3. Multiple scattering corrections for density profile unfolding from Compton scattering signals in reflection geometry

    International Nuclear Information System (INIS)

    Fernandez, Jorge E.; Badiali, Marco; Guidetti, Alessandro; Scot, Viviana

    2007-01-01

    Recently, a mathematical procedure was reported to unfold the density profile of wood panels from the measurement of the integrated scatter signal that contains prevalently the Compton component. An experimental device (patent claimed) has been used for these measurements. It uses reflection geometry to maximize the Compton signal. The influence of multiple scattering (MS) is not negligible as has been estimated using the Monte Carlo code MCSHAPE3D. However, Monte Carlo computations are time consuming. Therefore, in practice, the MS correction is computed off-line for few thicknesses of the specimen assuming known composition and density. Then, an original 2D interpolation algorithm is used to apply the MS correction to an arbitrary thickness scatterer, in order to improve the precision of the unfolded density profile in real time at the production line. The MS corrected density profiles are in good agreement with direct measurements performed with other means

  4. The Density Profiles of Massive, Relaxed Galaxy Clusters. I. The Total Density Over Three Decades in Radius

    Science.gov (United States)

    Newman, Andrew B.; Treu, Tommaso; Ellis, Richard S.; Sand, David J.; Nipoti, Carlo; Richard, Johan; Jullo, Eric

    2013-03-01

    Clusters of galaxies are excellent locations to probe the distribution of baryons and dark matter (DM) over a wide range of scales. We study a sample of seven massive (M 200 = 0.4-2 × 1015 M ⊙), relaxed galaxy clusters with centrally located brightest cluster galaxies (BCGs) at z = 0.2-0.3. Using the observational tools of strong and weak gravitational lensing, combined with resolved stellar kinematics within the BCG, we measure the total radial density profile, comprising both dark and baryonic matter, over scales of ~= 3-3000 kpc. We present Keck spectroscopy yielding seven new spectroscopic redshifts of multiply imaged sources and extended stellar velocity dispersion profiles of the BCGs. Lensing-derived mass profiles typically agree with independent X-ray estimates within ~= 15%, suggesting that departures from hydrostatic equilibrium are small and that the clusters in our sample (except A383) are not strongly elongated or compressed along the line of sight. The inner logarithmic slope γtot of the total density profile measured over r/r 200 = 0.003-0.03, where ρ_{tot} ∝ r^{-γ_{tot}}, is found to be nearly universal, with a mean langγtotrang = 1.16 ± 0.05(random)+0.05 -0.07 (systematic) and an intrinsic scatter σγ numerical simulations that contain only DM, despite the significant contribution of stellar mass on the scales we probe. The Navarro-Frenk-White profile characteristic of collisionless cold DM is a better description of the total mass density at radii >~ 5-10 kpc than that of DM alone. Hydrodynamical simulations that include baryons, cooling, and feedback currently provide a poorer match. We discuss the significance of our findings for understanding the physical processes governing the assembly of BCGs and cluster cores, particularly the influence of baryons on the inner DM halo.

  5. Earth-mass haloes and the emergence of NFW density profiles

    Science.gov (United States)

    Angulo, Raul E.; Hahn, Oliver; Ludlow, Aaron D.; Bonoli, Silvia

    2017-11-01

    We simulate neutralino dark matter (χDM) haloes from their initial collapse, at ˜ earth mass, up to a few percent solar. Our results confirm that the density profiles of the first haloes are described by a ˜r-1.5 power law. As haloes grow in mass, their density profiles evolve significantly. In the central regions, they become shallower and reach on average ˜r-1, the asymptotic form of an NFW profile. Using non-cosmological controlled simulations, we observe that temporal variations in the gravitational potential caused by major mergers lead to a shallowing of the inner profile. This transformation is more significant for shallower initial profiles and for a higher number of merging systems. Depending on the merger details, the resulting profiles can be shallower or steeper than NFW in their inner regions. Interestingly, mergers have a much weaker effect when the profile is given by a broken power law with an inner slope of -1 (such as NFW or Hernquist profiles). This offers an explanation for the emergence of NFW-like profiles: after their initial collapse, r-1.5 χDM haloes suffer copious major mergers, which progressively shallows the profile. Once an NFW-like profile is established, subsequent merging does not change the profile anymore. This suggests that halo profiles are not universal but rather a combination of (1) the physics of the formation of the microhaloes and (2) their early merger history - both set by the properties of the dark matter particle - as well as (3) the resilience of NFW-like profiles to perturbations.

  6. The effect of the cation alkyl chain length on density and diffusion in dialkylpyrrolidinium bis(mandelato)borate ionic liquids.

    Science.gov (United States)

    Filippov, Andrei; Taher, Mamoun; Shah, Faiz Ullah; Glavatskih, Sergei; Antzutkin, Oleg N

    2014-12-28

    The physicochemical properties of ionic liquids are strongly affected by the selective combination of the cations and anions comprising the ionic liquid. In particular, the length of the alkyl chains of ions has a clear influence on the ionic liquid's performance. In this paper, we study the self-diffusion of ions in a series of halogen-free boron-based ionic liquids (hf-BILs) containing bis(mandelato)borate anions and dialkylpyrrolidinium cations with long alkyl chains CnH2n+1 with n from 4 to 14 within a temperature range of 293-373 K. It was found that the hf-BILs with n = 4-7 have very similar diffusion coefficients, while hf-BILs with n = 10-14 exhibit two liquid sub-phases in almost the entire temperature range studied (293-353 K). Both liquid sub-phases differ in their diffusion coefficients, while values of the slower diffusion coefficients are close to those of hf-BILs with shorter alkyl chains. To explain the particular dependence of diffusion on the alkyl chain length, we examined the densities of the hf-BILs studied here. It was shown that the dependence of the density on the number of CH2 groups in long alkyl chains of cations can be accurately described using a "mosaic type" model, where regions of long alkyl chains of cations (named 'aliphatic' regions) and the residual chemical moieties in both cations and anions (named 'ionic' regions) give additive contributions. Changes in density due to an increase in temperature and the number of CH2 groups in the long alkyl chains of cations are determined predominantly by changes in the free volume of the 'ionic' regions, while 'aliphatic' regions are already highly compressed by van der Waals forces, which results in only infinitesimal changes in their free volumes with temperature.

  7. Quasi-quadrature interferometer for plasma density radial profile measurements

    International Nuclear Information System (INIS)

    Lowenthal, D.D.; Hoffman, A.L.

    1979-01-01

    A cw Mach Zehnder multichannel interferometer has been developed to measure time-dependent fractional fringe shifts with an accuracy of one-fortieth fringe. The design is quasi-quadrature in that known phase shifts, introduced in the reference beam, are time multiplexed with the normal reference beam. This technique requires only one detector per interferometer channel as compared to two detectors for most quadrature designs. The quadrature information makes the sense of density changes unambiguous, it automatically calibrates the instrument during the plasma event, and it makes fringe shift measurements virtually independent of fringe contrast fluctuations caused by plasma refractive and/or absorptive effects. The interferometer optical design is novel in that the electro-optic crystal used to introduce the 90 0 phase shifts is located in the common 2-mm-diam HeNe entrance beam to the interferometer, by exploiting polarization techniques, rather than in the expanded 1--2-cm reference beam itself. This arrangement greatly reduces the size, cost, and high-voltage requirements for the phase modulating crystal

  8. Confinement properties of JET plasmas with different temperature and density profiles

    International Nuclear Information System (INIS)

    Watkins, M.L.; Balet, B.; Bhatnagar, V.P.

    1989-01-01

    The confinement properties of plasmas with substantially different temperature and density profiles have been analysed. The effects of fast particles and energy pedestals on the overall confinement of plasma energy in limiter (L-mode) and X-point (L- and H-modes) discharges heated by NBI or ICRF or both are determined. The importance of the bootstrap current when such energy pedestals are formed is noted. Using sets of consistent experimental data, including ion temperature profile measurements, the local transport properties are compared in the L- and H-phases of a single null X-point medium density NBI heated discharge, the ''enhanced'' confinement phase of a limiter high density pellet-fuelled and ICRF heated discharge, the hot-ion phase of a double null X-point low density NBI heated discharge and the hot-ion and H-phases of a double null X-point low density high temperature NBI heated discharge. (author)

  9. Response of temperature and density profiles to heat deposition profile and its impact on global scaling in LHD

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, H.; Murakami, S.; Yamazaki, K. [and others

    2002-10-01

    Energy confinement and heat transport of net current-free NBI-heated plasmas in the Large Helical Device (LHD) are discussed with an emphasis on density dependence. Although the apparent density dependence of the energy confinement time has been demonstrated in a wide parameter range in LHD, the loss of this dependence has been observed in the high density regime under the specific condition. Broad heat deposition due to off-axis alignment and shallow penetration of neutral beams degrades the global energy confinement while the local heat transport maintains a clear temperature dependence lying between Bohm and gyro-Bohm characteristics. The central heat deposition inclines towards an intrinsic density dependence like {tau}{sub E} {proportional_to} (n-bar{sub e}/P){sup 0.6} from the saturated state. The broadening of the temperature profile due to the broad heat deposition profile contrasts with the invariant property which has observed widely as profile consistency and stiffness in tokamak experiments. (author)

  10. Numerical analysis of the optimal length and profile of a linearly chirped fiber Bragg grating for dispersion compensation.

    Science.gov (United States)

    Thibault, S; Lauzon, J; Cliche, J F; Martin, J; Duguay, M A; Têtu, M

    1995-03-15

    We propose a theoretical investigation of the length and coupling profile of a linearly chirped fiber Bragg grating for maximum dispersion compensation in a repeaterless optical communication system. The system consists of 100 km of standard optical fiber in which a 1550-nm signal, directly modulated at 2.5 Gbits/s, is launched. We discuss the results obtained with 6-, 4.33-, and 1-cm-long linearly chirped fiber Bragg gratings having Gaussian and uniform coupling profiles. We numerically show that a 4.33-cm-long chirped fiber Bragg grating having a uniform coupling profile is capable of compensating efficiently for the dispersion of our optical communication system.

  11. Real-time control of the plasma density profile on ASDEX upgrade

    International Nuclear Information System (INIS)

    Mlynek, Alexander

    2010-01-01

    The tokamak concept currently is the most promising approach to future power generation by controlled thermonuclear fusion. The spatial distribution of the particle density in the toroidally confined fusion plasma is of particular importance. This thesis work therefore focuses on the question as to what extent the shape of the density profile can be actively controlled by a feedback loop in the fusion experiment ASDEX Upgrade. There are basically two essential requirements for such feedback control of the density profile, which has been experimentally demonstrated within the scope of this thesis work: On the one hand, for this purpose the density profile must be continuously calculated under real-time constraints during a plasma discharge. The calculation of the density profile is based on the measurements of a sub-millimeter interferometer, which provides the line-integrated electron density along 5 chords through the plasma. Interferometric density measurements can suffer from counting errors by integer multiples of 2π when detecting the phase difference between a probing and a reference beam. As such measurement errors have severe impact on the reconstructed density profile, one major part of this work consists in the development of new readout electronics for the interferometer, which allows for detection of such measurement errors in real-time with high reliability. A further part of this work is the design of a computer algorithm which reconstructs the spatial distribution of the plasma density from the line-integrated measurements. This algorithm has to be implemented on a computer which communicates the measured data to other computers in real-time, especially to the tokamak control system. On the other hand, a second fundamental requirement for the successful implementation of a feedback controller is the identification of at least one actuator which enables a modification of the density profile. Here, electron cyclotron resonance heating (ECRH) has been

  12. Association between leukocyte telomere length and bone mineral density in women 25-93 years of age

    DEFF Research Database (Denmark)

    Nielsen, Barbara Rubek; Linneberg, Allan; Bendix, Laila

    2015-01-01

    completed a health and lifestyle questionnaire. The associations were estimated by regression models that considered age, body mass index (BMI), menopause, physical activity, alcohol consumption and smoking habits. We found a statistically significant unadjusted association between LTL and age (estimate......Leukocyte telomere length (LTL) and bone mineral density (BMD) are associated with health and mortality. Because osteoporosis is an age-related condition and LTL is considered to be a biomarker of aging, we hypothesized that shorter LTL could predict lower BMD. The aim of our study was to assess...... whether there is an association of LTL with BMD and to determine whether this possible association is independent of age. The BMDs of the lumbar spine (LS), femoral neck (FN) and total hip (TH) were evaluated in 460 women using DXA. LTL was analyzed using quantitative polymerase chain reaction. The women...

  13. Axial Length Variation Impacts on Superficial Retinal Vessel Density and Foveal Avascular Zone Area Measurements Using Optical Coherence Tomography Angiography.

    Science.gov (United States)

    Sampson, Danuta M; Gong, Peijun; An, Di; Menghini, Moreno; Hansen, Alex; Mackey, David A; Sampson, David D; Chen, Fred K

    2017-06-01

    To evaluate the impact of image magnification correction on superficial retinal vessel density (SRVD) and foveal avascular zone area (FAZA) measurements using optical coherence tomography angiography (OCTA). Participants with healthy retinas were recruited for ocular biometry, refraction, and RTVue XR Avanti OCTA imaging with the 3 × 3-mm protocol. The foveal and parafoveal SRVD and FAZA were quantified with custom software before and after correction for magnification error using the Littman and the modified Bennett formulae. Relative changes between corrected and uncorrected SRVD and FAZA were calculated. Forty subjects were enrolled and the median (range) age of the participants was 30 (18-74) years. The mean (range) spherical equivalent refractive error was -1.65 (-8.00 to +4.88) diopters and mean (range) axial length was 24.42 mm (21.27-28.85). Images from 13 eyes were excluded due to poor image quality leaving 67 for analysis. Relative changes in foveal and parafoveal SRVD and FAZA after correction ranged from -20% to +10%, -3% to +2%, and -20% to +51%, respectively. Image size correction in measurements of foveal SRVD and FAZA was greater than 5% in 51% and 74% of eyes, respectively. In contrast, 100% of eyes had less than 5% correction in measurements of parafoveal SRVD. Ocular biometry should be performed with OCTA to correct image magnification error induced by axial length variation. We advise caution when interpreting interocular and interindividual comparisons of SRVD and FAZA derived from OCTA without image size correction.

  14. Avalanche consumption and the stationary regions of the density profile around the droplets in the theory of condensation

    OpenAIRE

    Kurasov, V.

    1998-01-01

    The contradiction between the stationary aproach to the density profile and the avalanche character of the metastable phase consumption is investigated. The exact solution for the metastable phase profile is obtained. The reconsidered value for the special parameter responsible for the hierarchy in the structure of the density profile around the droplet is presented.

  15. The diverse density profiles of galaxy clusters with self-interacting dark matter plus baryons

    Science.gov (United States)

    Robertson, Andrew; Massey, Richard; Eke, Vincent; Tulin, Sean; Yu, Hai-Bo; Bahé, Yannick; Barnes, David J.; Bower, Richard G.; Crain, Robert A.; Dalla Vecchia, Claudio; Kay, Scott T.; Schaller, Matthieu; Schaye, Joop

    2018-02-01

    We present the first simulated galaxy clusters (M200 > 1014 M⊙) with both self-interacting dark matter (SIDM) and baryonic physics. They exhibit a greater diversity in both dark matter and stellar density profiles than their counterparts in simulations with collisionless dark matter (CDM), which is generated by the complex interplay between dark matter self-interactions and baryonic physics. Despite variations in formation history, we demonstrate that analytical Jeans modelling predicts the SIDM density profiles remarkably well, and the diverse properties of the haloes can be understood in terms of their different final baryon distributions.

  16. ICRF power-deposition profiles, heating and confinement of monster sawtooth and peaked-density profile discharges in JET

    International Nuclear Information System (INIS)

    Bhatnagar, V.P.; Taroni, A.; Ellis, J.J.; Jacquinot, J.; Start, D.F.H.

    1989-01-01

    The ion cyclotron resonance heating of monster sawtooth (period greater than the energy confinement time) and pellet-fueled peaked-density profiles in limiter discharges of JET Tokamak are studied. The monster sawtooth is a characteristic JET regime which is related to fast ions generated during the minority ion heating. In the ICRF heating of peaked-density profile discharges, we find typically the T i0 is higher roughly by a factor of 2 and T e0 roughly by 35% at a fixed P TOT /n e0 when compared to non-peaked profile cases. Here, T e0 and T i0 are central electron and ion temperatures, respectively, n e0 is the central electron density and P TOT is the total input power. The ion heating is improved in the pellet case, in part, due to a higher collisionality between the background ions and the energetic minority, but more significantly by a reduction of local ion energy transport in the central region. The transport-code simulation of these discharges reveals that there is a reduction of both χ e and χ i in the central region of the plasma in the ICRF heated peaked-profile discharges where χ e and χ i are the electron and ion heat conductivities, respectively. The improvement of confinement is not explained quantitatively by any of the existing η i -driven turbulence theories as the n i parameter (η i = d ln T i /d ln n i where T i is the ion temperature and n i is the ion density), instead of dropping below the critical value, remains above it for most of the duration of the improved confinement phase. The physical mechanism(s) that plays a role in this improvement is not yet clear. (author)

  17. Fitting of the Thomson scattering density and temperature profiles on the COMPASS tokamak

    International Nuclear Information System (INIS)

    Stefanikova, E.; Peterka, M.; Bohm, P.; Bilkova, P.; Aftanas, M.; Urban, J.; Hron, M.; Panek, R.; Sos, M.

    2016-01-01

    A new technique for fitting the full radial profiles of electron density and temperature obtained by the Thomson scattering diagnostic in H-mode discharges on the COMPASS tokamak is described. The technique combines the conventionally used modified hyperbolic tangent function for the edge transport barrier (pedestal) fitting and a modification of a Gaussian function for fitting the core plasma. Low number of parameters of this combined function and their straightforward interpretability and controllability provide a robust method for obtaining physically reasonable profile fits. Deconvolution with the diagnostic instrument function is applied on the profile fit, taking into account the dependence on the actual magnetic configuration.

  18. On the contact values of the density profiles in an electric double layer using density functional theory

    Directory of Open Access Journals (Sweden)

    L.B. Bhuiyan

    2012-06-01

    Full Text Available A recently proposed, local second contact value theorem [Henderson D., Boda D., J. Electroanal. Chem., 2005, Vol. 582, 16] for the charge profile of an electric double layer is used in conjunction with existing Monte Carlo data from the literature to assess the contact behavior of the electrode-ion distributions predicted by the density functional theory. The results for the contact values of the co- and counterion distributions and their product are obtained for the symmetric valency, restricted primitive model planar double layer for a range of electrolyte concentrations and temperatures. Overall the theoretical results satisfy the second contact value theorem reasonably well the agreement with the simulations being semi-quantitative or better. The product of the co- and counterion contact values as a function of the electrode surface charge density is qualitative with the simulations with increasing deviations at higher concentrations.

  19. Fast electron current density profile and diffusion studies during LHCD in PBX-M

    Energy Technology Data Exchange (ETDEWEB)

    Jones, S.E.; Kesner, J.; Luckhardt, S.; Paoletti, F. [Massachusetts Inst. of Tech., Cambridge, MA (United States). Plasma Fusion Center; von Goeler, S.; Bernabei, S.; Kaita, R. [Princeton Univ., NJ (United States). Plasma Physics Lab.; Rimini, F. [JET Joint Undertaking, Abingdon (United Kingdom)

    1993-08-01

    Successful current profile control experiments using lower hybrid current drive (LCHD) clearly require knowledge of (1) the location of the driven fast electrons and (2) the ability to maintain that location from spreading due to radial diffusion. These issues can be addressed by examining the data from the hard x-ray camera on PBX-M, a unique diagnostic producing two-dimensional, time resolved tangential images of fast electron bremsstrahlung. Using modeling, these line-of-sight images are inverted to extract a radial fast electron current density profile. We note that ``hollow`` profiles have been observed, indicative of off-axis current drive. These profiles can then be used to calculate an upper bound for an effective fast electron diffusion constant: assuming an extremely radially narrow lower hybrid absorption profile and a transport model based on Rax and Moreau, a model fast electron current density profile is calculated and compared to the experimentally derived profile. The model diffusion constant is adjusted until a good match is found. Applied to steady-state quiescent modes on PBX-M, we obtain an upper limit for an effective diffusion constant of about D*=1.1 m{sup 2}/sec.

  20. Measurement of the density profile of pure and seeded molecular beams by femtosecond ion imaging

    NARCIS (Netherlands)

    Meng, C.; Janssen, M.H.M.

    2015-01-01

    Here, we report on femtosecond ion imaging experiments to measure the density profile of a pulsed supersonic molecular beam. Ion images are measured for both a molecular beam and bulk gas under identical experimental conditions via femtosecond multiphoton ionization of Xe atoms. We report the

  1. Methodology for extraction of space charge density profiles at nanoscale from Kelvin probe force microscopy measurements.

    Science.gov (United States)

    Villeneuve-Faure, C; Boudou, L; Makasheva, K; Teyssedre, G

    2017-12-15

    To understand the physical phenomena occurring at metal/dielectric interfaces, determination of the charge density profile at nanoscale is crucial. To deal with this issue, charges were injected applying a DC voltage on lateral Al-electrodes embedded in a SiN x thin dielectric layer. The surface potential induced by the injected charges was probed by Kelvin probe force microscopy (KPFM). It was found that the KPFM frequency mode is a better adapted method to probe accurately the charge profile. To extract the charge density profile from the surface potential two numerical approaches based on the solution to Poisson's equation for electrostatics were investigated: the second derivative model method, already reported in the literature, and a new 2D method based on the finite element method (FEM). Results highlight that the FEM is more robust to noise or artifacts in the case of a non-flat initial surface potential. Moreover, according to theoretical study the FEM appears to be a good candidate for determining charge density in dielectric films with thicknesses in the range from 10 nm to 10 μm. By applying this method, the charge density profile was determined at nanoscale, highlighting that the charge cloud remains close to the interface.

  2. Methodology for extraction of space charge density profiles at nanoscale from Kelvin probe force microscopy measurements

    Science.gov (United States)

    Villeneuve-Faure, C.; Boudou, L.; Makasheva, K.; Teyssedre, G.

    2017-12-01

    To understand the physical phenomena occurring at metal/dielectric interfaces, determination of the charge density profile at nanoscale is crucial. To deal with this issue, charges were injected applying a DC voltage on lateral Al-electrodes embedded in a SiN x thin dielectric layer. The surface potential induced by the injected charges was probed by Kelvin probe force microscopy (KPFM). It was found that the KPFM frequency mode is a better adapted method to probe accurately the charge profile. To extract the charge density profile from the surface potential two numerical approaches based on the solution to Poisson’s equation for electrostatics were investigated: the second derivative model method, already reported in the literature, and a new 2D method based on the finite element method (FEM). Results highlight that the FEM is more robust to noise or artifacts in the case of a non-flat initial surface potential. Moreover, according to theoretical study the FEM appears to be a good candidate for determining charge density in dielectric films with thicknesses in the range from 10 nm to 10 μm. By applying this method, the charge density profile was determined at nanoscale, highlighting that the charge cloud remains close to the interface.

  3. Magnetically Filtered Faraday Probe for Measuring the Ion Current Density Profile of a Hall Thruster

    National Research Council Canada - National Science Library

    Rovey, Joshua L; Walker, Mitchell L. R; Gallimore, Alec D; Peterson, Peter Y

    2006-01-01

    .... In this study, a MFFP, Faraday probe with a reduced acceptance angle (BFP), and nude Faraday probe are used to measure the ion current density profile of a 5 kW Hall thruster operating over the range of 300-500 V and 5-10 mg...

  4. Low-latitude Model Electron Density Profiles using the IRI and CCIR ...

    African Journals Online (AJOL)

    empirical basis with the International Reference Ionosphere (IRI-90) and the CCIR models. Electron density profiles are computed using the median values of ionospheric data routinely scaled from ionograms at Ibadan (7.40N, 3.90E) and ...

  5. Effects of time-series length and gauge network density on rainfall climatology estimates in Latin America

    Science.gov (United States)

    Maeda, E.; Arevalo, J.; Carmona-Moreno, C.

    2012-04-01

    Despite recent advances in the development of satellite sensors for monitoring precipitation at high spatial and temporal resolutions, the assessment of rainfall climatology still relies strongly on ground-station measurements. The Global Historical Climatology Network (GHCN) is one of the most popular stations database available for the international community. Nevertheless, the spatial distribution of these stations is not always homogeneous and the record length largely varies for each station. This study aimed to evaluate how the number of years recorded in the GHCN stations and the density of the network affect the uncertainties of annual rainfall climatology estimates in Latin America. The method applied was divided in two phases. In the first phase, Monte Carlo simulations were performed to evaluate how the number of samples and the characteristics of rainfall regime affect estimates of annual average rainfall. The simulations were performed using gamma distributions with pre-defined parameters, which generated synthetic annual precipitation records. The average and dispersion of the synthetic records were then estimated through the L-moments approach and compared with the original probability distribution that was used to produce the samples. The number of records (n) used in the simulation varied from 10 to 150, reproducing the range of number of years typically found in meteorological stations. A power function, in the form RMSE= f(n) = c.na, where the coefficients were defined as a function of the rainfall statistical dispersion, was applied to fit the errors. In the second phase of the assessment, the results of the simulations were extrapolated to real records obtained by the GHCN over Latin America, creating estimates of errors associated with number of records and rainfall characteristics in each station. To generate a spatially-explicit representation of the uncertainties, the errors in each station were interpolated using the inverse distance

  6. Psychological Profiles in the Prediction of Leukocyte Telomere Length in Healthy Individuals.

    Directory of Open Access Journals (Sweden)

    Louisia Starnino

    Full Text Available Shorter telomere length (TL may signal premature cellular aging and increased risk for disease. While depression and psychosocial stress have been associated with shorter telomeres, other psychological risk factors for cardiovascular disease have received less attention.To evaluate the association between TL and psychological risk factors (symptoms of anxiety and depression, hostility and defensiveness traits for heart disease, and to examine whether chronological age and sex moderate the associations observed.132 healthy men and women (Mage = 45.34 years completed the Marlowe-Crowne Social Desirability Scale, the Beck Depression Inventory II, The Beck Anxiety Inventory and the Cook-Medley Hostility Scale. Relative TL was measured by quantitative polymerase chain reaction (PCR of total genomic DNA samples. A series of hierarchical linear regressions were performed controlling for pertinent covariates.Shorter TL was observed among individuals high in defensiveness (β = -.221 and depressive symptoms (β = -.213, as well as in those with less hostility (β =.256 and anxiety (β =.220(all Ps<.05. Psychological variables explained 19% of the variance over and above that explained by covariates (age, sex, exercise, alcohol consumption, systemic inflammation, and 24-hr mean arterial pressure. Age moderated the relation between TL and defensiveness (β =.179, p =.03. Sex did not influence any of the relations.Telomere length is associated with psychological burden though the direction of effect differs depending on the psychological variables under study. Further research is needed to determine the reasons for and implications of these seemingly contradictory findings.

  7. Analysis of Total Electron Content and Electron Density Profile during Different Geomagnetic Storms

    Science.gov (United States)

    Chapagain, N. P.; Rana, B.; Adhikari, B.

    2017-12-01

    Total Electron content (TEC) and electron density are the key parameters in the mitigation of ionospheric effects on radio communication system. Detail study of the TEC and electron density variations has been carried out during geomagnetic storms, with longitude and latitude, for four different locations: (13˚N -17˚N, 88˚E -98˚E), (30˚N-50˚N, 120˚W -95˚W), (29˚S-26˚S, 167˚W-163˚W,) and (60˚S-45˚S, 120˚W-105˚W) using the Gravity Recovery and Climate Experiment (GRACE) satellite observations. In order to find the geomagnetic activity, the solar wind parameters such as north-south component of inter planetary magnetic field (Bz), plasma drift velocity (Vsw), flow pressure (nPa), AE, Dst and Kp indices were obtained from Operating Mission as Nodes on the Internet (OMNI) web system. The data for geomagnetic indices have been correlated with the TEC and electron density for four different events of geomagnetic storms on 6 April 2008, 27 March 2008, 4 September 2008, and 11 October 2008. The result illustrates that the observed TEC and electron density profile significantly vary with longitudes and latitudes. This study illustrates that the values of TEC and the vertical electron density profile are influenced by the solar wind parameters associated with solar activities. The peak values of electron density and TEC increase as the geomagnetic storms become stronger. Similarly, the electron density profile varies with altitudes, which peaks around the altitude range of about 250- 350 km, depending on the strength of geomagnetic storms. The results clearly show that the peak electron density shifted to higher altitude (from about 250 km to 350 km) as the geomagnetic disturbances becomes stronger.

  8. A thermodynamic perturbation theory for the surface tension and ion density profile of a liquid metal

    International Nuclear Information System (INIS)

    Evans, R.; Kumaravadivel, R.

    1976-01-01

    A simple scheme for determining the ion density profile and the surface tension of a liquid metal is described. Assuming that the interaction between metallic pseudo-ions is of the form introduced by Evans, an approximate expression for the excess free energy of the system is derived using the thermodynamic perturbation theory of Weeks, Chandler and Anderson. This excess free energy is then minimized with respect to a parameter which specifies the ion density profile, and the surface tension is given directly. From a consideration of the dependence of the interionic forces on the electron density it is predicted that the ions should take up a very steep density profile at the liquid metal surface. This behaviour is contrasted with that to be expected for rare-gas fluids in which the interatomic forces are density-independent. The values of the surface tension calculated for liquid Na, K and Al from a simplified version of the theory are in reasonable agreement with experiment. (author)

  9. Influence of anterior chamber depth, anterior chamber volume, axial length, and lens density on postoperative endothelial cell loss.

    Science.gov (United States)

    Reuschel, Anna; Bogatsch, Holger; Oertel, Nicole; Wiedemann, Renate

    2015-05-01

    To evaluate the influence of anterior chamber depth (ACD), anterior chamber volume (ACV), lens density (LD), and axial length (AL) as risk factors on endothelial cell loss 3 months after cataract surgery. We enrolled 47 patients with senile cataract who were operated between July 2012 and March 2013 by the same surgeon using torsional phacoemulsification. Preoperatively, we measured ACD, ACV, and LD using the Oculus Pentacam®. The AL was determined using the IOL Master®. Primary outcomes were central endothelial density (ECD) and corrected distance visual acuity (CDVA) 3 months after surgery We evaluated the effect of ACD, ACV, LD, and AL as possible risk factors of postoperative percentage endothelial cell loss (ECL). The median age was 72 years. The median CDVA before surgery was 0.5 improving to 1.0 postoperatively. The median ECL was 5.2 % (range 1.7 %-7.6 %). These results are comparable to our previous study (median ECL 6.9 % after 3 months) [Reuschel et al. (2010) J Cataract Refract Surg]. The median ACD in our study was 2.56 mm (range 2.26 mm-2.8 mm). Median ACV was 144 mm(3) (range 121 mm(3)-158 mm(3)]. The median LD was 12.4 (range 11.4-13.7). Median AL was 23.1 mm (range 22.7 mm-23.9 mm). Our correlation analysis showed no significant correlation between ACD, ACV, LD, AL, and postoperative ECL. ACD, ACV, AL, and LD were not identified as risk factors of postoperative endothelial cell loss in our analysis.

  10. Loss of PiT-2 results in abnormal bone development and decreased bone mineral density and length in mice.

    Science.gov (United States)

    Yamada, Shunsuke; Wallingford, Mary C; Borgeia, Suhaib; Cox, Timothy C; Giachelli, Cecilia M

    2018-01-01

    Normal bone mineralization requires phosphate oversaturation in bone matrix vesicles, as well as normal regulation of phosphate metabolism via the interplay among bone, intestine, and kidney. In turn, derangement of phosphate metabolism greatly affects bone function and structure. The type III sodium-dependent phosphate transporters, PiT-1 and PiT-2, are believed to be important in tissue phosphate metabolism and physiological bone formation, but their requirement and molecular roles in bone remain poorly investigated. In order to decipher the role of PiT-2 in bone, we examined normal bone development, growth, and mineralization in global PiT-2 homozygous knockout mice. PiT-2 deficiency resulted in reduced vertebral column, femur, and tibia length as well as mandibular dimensions. Micro-computed tomography analysis revealed that bone mineral density in the mandible, femur, and tibia were decreased, indicating that maintenance of bone function and structure is impaired in both craniofacial and long bones of PiT-2 deficient mice. Both cortical and trabecular thickness and mineral density were reduced in PiT-2 homozygous knockout mice compared with wild-type mice. These results suggest that PiT-2 is involved in normal bone development and growth and plays roles in cortical and trabecular bone metabolism feasibly by regulating local phosphate transport and mineralization processes in the bone. Further studies that evaluate bone cell-specific loss of PiT-2 are now warranted and may yield insight into complex mechanisms of bone development and growth, leading to identification of new therapeutic options for patients with bone diseases. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Bayesian modeling of JET Li-BES for edge electron density profiles using Gaussian processes

    Science.gov (United States)

    Kwak, Sehyun; Svensson, Jakob; Brix, Mathias; Ghim, Young-Chul; JET Contributors Collaboration

    2015-11-01

    A Bayesian model for the JET lithium beam emission spectroscopy (Li-BES) system has been developed to infer edge electron density profiles. The 26 spatial channels measure emission profiles with ~15 ms temporal resolution and ~1 cm spatial resolution. The lithium I (2p-2s) line radiation in an emission spectrum is calculated using a multi-state model, which expresses collisions between the neutral lithium beam atoms and the plasma particles as a set of differential equations. The emission spectrum is described in the model including photon and electronic noise, spectral line shapes, interference filter curves, and relative calibrations. This spectral modeling gets rid of the need of separate background measurements for calculating the intensity of the line radiation. Gaussian processes are applied to model both emission spectrum and edge electron density profile, and the electron temperature to calculate all the rate coefficients is obtained from the JET high resolution Thomson scattering (HRTS) system. The posterior distributions of the edge electron density profile are explored via the numerical technique and the Markov chain Monte Carlo (MCMC) samplings. See the Appendix of F. Romanelli et al., Proceedings of the 25th IAEA Fusion Energy Conference 2014, Saint Petersburg, Russia.

  12. A two-dimensional regularization algorithm for density profile evaluation from broadband reflectometry

    International Nuclear Information System (INIS)

    Nunes, F.; Varela, P.; Silva, A.; Manso, M.; Santos, J.; Nunes, I.; Serra, F.; Kurzan, B.; Suttrop, W.

    1997-01-01

    Broadband reflectometry is a current technique that uses the round-trip group delays of reflected frequency-swept waves to measure density profiles of fusion plasmas. The main factor that may limit the accuracy of the reconstructed profiles is the interference of the probing waves with the plasma density fluctuations: plasma turbulence leads to random phase variations and magneto hydrodynamic activity produces mainly strong amplitude and phase modulations. Both effects cause the decrease, and eventually loss, of signal at some frequencies. Several data processing techniques can be applied to filter and/or interpolate noisy group delay data obtained from turbulent plasmas with a single frequency sweep. Here, we propose a more powerful algorithm performing two-dimensional regularization (in space and time) of data provided by multiple consecutive frequency sweeps, which leads to density profiles with improved accuracy. The new method is described and its application to simulated data corrupted by noise and missing data is considered. It is shown that the algorithm improves the identification of slowly varying plasma density perturbations by attenuating the effect of fast fluctuations and noise contained in experimental data. First results obtained with this method in ASDEX Upgrade tokamak are presented. copyright 1997 American Institute of Physics

  13. A two-dimensional regularization algorithm for density profile evaluation from broadband reflectometry

    Science.gov (United States)

    Nunes, F.; Varela, P.; Silva, A.; Manso, M.; Santos, J.; Nunes, I.; Serra, F.; Kurzan, B.; Suttrop, W.

    1997-01-01

    Broadband reflectometry is a current technique that uses the round-trip group delays of reflected frequency-swept waves to measure density profiles of fusion plasmas. The main factor that may limit the accuracy of the reconstructed profiles is the interference of the probing waves with the plasma density fluctuations: plasma turbulence leads to random phase variations and magneto hydrodynamic activity produces mainly strong amplitude and phase modulations. Both effects cause the decrease, and eventually loss, of signal at some frequencies. Several data processing techniques can be applied to filter and/or interpolate noisy group delay data obtained from turbulent plasmas with a single frequency sweep. Here, we propose a more powerful algorithm performing two-dimensional regularization (in space and time) of data provided by multiple consecutive frequency sweeps, which leads to density profiles with improved accuracy. The new method is described and its application to simulated data corrupted by noise and missing data is considered. It is shown that the algorithm improves the identification of slowly varying plasma density perturbations by attenuating the effect of fast fluctuations and noise contained in experimental data. First results obtained with this method in ASDEX Upgrade tokamak are presented.

  14. Quantum Hall states of atomic Bose gases: Density profiles in single-layer and multilayer geometries

    International Nuclear Information System (INIS)

    Cooper, N. R.; Lankvelt, F. J. M. van; Reijnders, J. W.; Schoutens, K.

    2005-01-01

    We describe the density profiles of confined atomic Bose gases in the high-rotation limit, in single-layer and multilayer geometries. We show that, in a local-density approximation, the density in a single layer shows a landscape of quantized steps due to the formation of incompressible liquids, which are analogous to fractional quantum Hall liquids for a two-dimensional electron gas in a strong magnetic field. In a multilayered setup we find different phases, depending on the strength of the interlayer tunneling t. We discuss the situation where a vortex lattice in the three-dimensional condensate (at large tunneling) undergoes quantum melting at a critical tunneling t c 1 . For tunneling well below t c 1 one expects weakly coupled or isolated layers, each exhibiting a landscape of quantum Hall liquids. After expansion, this gives a radial density distribution with characteristic features (cusps) that provide experimental signatures of the quantum Hall liquids

  15. Dwarf galaxy dark matter density profiles inferred from stellar and gas kinematics

    International Nuclear Information System (INIS)

    Adams, Joshua J.; Simon, Joshua D.; Fabricius, Maximilian H.; Bender, Ralf; Thomas, Jens; Van den Bosch, Remco C. E.; Van de Ven, Glenn; Barentine, John C.; Gebhardt, Karl; Hill, Gary J.; Murphy, Jeremy D.; Swaters, R. A.

    2014-01-01

    We present new constraints on the density profiles of dark matter (DM) halos in seven nearby dwarf galaxies from measurements of their integrated stellar light and gas kinematics. The gas kinematics of low-mass galaxies frequently suggest that they contain constant density DM cores, while N-body simulations instead predict a cuspy profile. We present a data set of high-resolution integral-field spectroscopy on seven galaxies and measure the stellar and gas kinematics simultaneously. Using Jeans modeling on our full sample, we examine whether gas kinematics in general produce shallower density profiles than are derived from the stars. Although two of the seven galaxies show some localized differences in their rotation curves between the two tracers, estimates of the central logarithmic slope of the DM density profile, γ, are generally robust. The mean and standard deviation of the logarithmic slope for the population are γ = 0.67 ± 0.10 when measured in the stars and γ = 0.58 ± 0.24 when measured in the gas. We also find that the halos are not under-concentrated at the radii of half their maximum velocities. Finally, we search for correlations of the DM density profile with stellar velocity anisotropy and other baryonic properties. Two popular mechanisms to explain cored DM halos are an exotic DM component or feedback models that strongly couple the energy of supernovae into repeatedly driving out gas and dynamically heating the DM halos. While such models do not yet have falsifiable predictions that we can measure, we investigate correlations that may eventually be used to test models. We do not find a secondary parameter that strongly correlates with the central DM density slope, but we do find some weak correlations. The central DM density slope weakly correlates with the abundance of α elements in the stellar population, anti-correlates with H I fraction, and anti-correlates with vertical orbital anisotropy. We expect, if anything, the opposite of these

  16. Measuring Density Profiles of Electrons and Heavy Particles in a Stable Axially Blown Arc

    Science.gov (United States)

    Carstensen, J.; Stoller, P.; Galletti, B.; Doiron, C. B.; Sokolov, A.

    2017-08-01

    Two-color spatial carrier wave interferometry employing pulsed 532- and 671-nm lasers is used to measure the electron-density and heavy-particle-density profiles in the stagnation point of a stable, axially blown arc in argon for currents of 50 to 200 A and stagnation point pressures of 0.2 to 16 bar. This technique takes advantage of the fact that the free-electron contribution to the refractive index depends strongly on the wavelength, while that of the heavy particles does not. The high spatial resolution achieved allows the hot core of the arc to be readily distinguished from the surrounding boundary layer. A custom-built test device is used to ensure flow conditions that lead to a stable, axisymmetric arc; this permits the reconstruction of the density and temperature profiles using a single projection (interferometric image) of the refractive-index distribution through the arc (at two wavelengths). The arc radius determined from the heavy-particle density decreases with increasing stagnation pressure and increases with the current. These measurements are in good agreement with a simple axially blown arc model taking into account Ohmic heating, radiation losses, and enthalpy flow for core temperatures of approximately 16 500 K. The measured electron density at the center of the arc agrees well with a prediction based on local thermodynamic equilibrium.

  17. Aphid aerial density profiles are consistent with turbulent advection amplifying flight behaviours: abandoning the epithet 'passive'.

    Science.gov (United States)

    Reynolds, Andy M; Reynolds, Don R

    2009-01-07

    Seminal field studies led by C. G. Johnson in the 1940s and 1950s showed that aphid aerial density diminishes with height above the ground such that the linear regression coefficient, b, of log density on log height provides a single-parameter characterization of the vertical density profile. This coefficient decreases with increasing atmospheric stability, ranging from -0.27 for a fully convective boundary layer to -2.01 for a stable boundary layer. We combined a well-established Lagrangian stochastic model of atmospheric dispersal with simple models of aphid behaviour in order to account for the range of aerial density profiles. We show that these density distributions are consistent with the aphids producing just enough lift to become neutrally buoyant when they are in updraughts and ceasing to produce lift when they are in downdraughts. This active flight behaviour in a weak flier is thus distinctly different from the aerial dispersal of seeds and wingless arthropods, which is passive once these organisms have launched into the air. The novel findings from the model indicate that the epithet 'passive' often applied to the windborne migration of small winged insects is misleading and should be abandoned. The implications for the distances traversed by migrating aphids under various boundary-layer conditions are outlined.

  18. Analytical solution for the mode conversion equations with steep exponential density profiles

    International Nuclear Information System (INIS)

    Alava, M.J.; Heikkinen, J.A.

    1992-01-01

    A general analytical solution for the converted power from the fast magnetosonic wave to an ion Bernstein wave in a magnetized plasma with an exponential steeply increasing density profile is given in the closed form. The solution covers both the conversion at the lower-hybrid resonance and the conversion through the density gradient for small parallel wave numbers. As an application, the conversion coefficients at the scrape-off layer plasma are estimated in the context of ion cyclotron heating of a tokamak plasma

  19. Reconstruction and analysis of temperature and density spatial profiles inertial confinement fusion implosion cores

    International Nuclear Information System (INIS)

    Mancini, R. C.

    2007-01-01

    We discuss several methods for the extraction of temperature and density spatial profiles in inertial confinement fusion implosion cores based on the analysis of the x-ray emission from spectroscopic tracers added to the deuterium fuel. The ideas rely on (1) detailed spectral models that take into account collisional-radiative atomic kinetics, Stark broadened line shapes, and radiation transport calculations, (2) the availability of narrow-band, gated pinhole and slit x-ray images, and space-resolved line spectra of the core, and (3) several data analysis and reconstruction methods that include a multi-objective search and optimization technique based on a novel application of Pareto genetic algorithms to plasma spectroscopy. The spectroscopic analysis yields the spatial profiles of temperature and density in the core at the collapse of the implosion, and also the extent of shell material mixing into the core. Results are illustrated with data recorded in implosion experiments driven by the OMEGA and Z facilities

  20. Method of measuring a profile of the density of charged particles in a particle beam

    International Nuclear Information System (INIS)

    Hyman, L.G.; Jankowski, D.J.

    1975-01-01

    A profile of the relative density of charged particles in a beam is obtained by disposing a number of rods parallel to each other in a plane perpendicular to the beam and shadowing the beam. A second number of rods is disposed perpendicular to the first rods in a plane perpendicular to the beam and also shadowing the beam. Irradiation of the rods by the beam of charged particles creates radioactive isotopes in a quantity proportional to the number of charged particles incident upon the rods. Measurement of the radioactivity of each of the rods provides a measure of the quantity of radioactive material generated thereby and, together with the location of the rods, provides information sufficient to identify a profile of the density of charged particles in the beam

  1. The Splashback Feature around DES Galaxy Clusters: Galaxy Density and Weak Lensing Profiles

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Chihway; et al.

    2017-10-18

    Splashback refers to the process of matter that is accreting onto a dark matter halo reaching its first orbital apocenter and turning around in its orbit. The cluster-centric radius at which this process occurs, r_sp, defines a halo boundary that is connected to the dynamics of the cluster, in contrast with other common halo boundary definitions such as R_200. A rapid decline in the matter density profile of the halo is expected near r_sp. We measure the galaxy number density and weak lensing mass profiles around RedMapper galaxy clusters in the first year Dark Energy Survey (DES) data. For a cluster sample with mean mass ~2.5 x 10^14 solar masses, we find strong evidence of a splashback-like steepening of the galaxy density profile and measure r_sp=1.16 +/- 0.08 Mpc/h, consistent with earlier SDSS measurements of More et al. (2016) and Baxter et al. (2017). Moreover, our weak lensing measurement demonstrates for the first time the existence of a splashback-like steepening of the matter profile of galaxy clusters. We measure r_sp=1.28 +/- 0.18 Mpc/h from the weak lensing data, in good agreement with our galaxy density measurements. Applying our analysis to different cluster and galaxy samples, we find that consistent with LambdaCDM simulations, r_sp scales with R_200m and does not evolve with redshift over the redshift range of 0.3--0.6. We also find that potential systematic effects associated with the RedMapper algorithm may impact the location of r_sp, in particular the choice of scale used to estimate cluster richness. We discuss progress needed to understand the systematic uncertainties and fully exploit forthcoming data from DES and future surveys, emphasizing the importance of more realistic mock catalogs and independent cluster samples.

  2. Dependence of capacitance of metal-molten salt interface on local density profiles near electrode

    International Nuclear Information System (INIS)

    Ballone, P.; Pastore, G.; Tosi, M.P.; Painter, K.R.; Grout, P.J.; March, N.H.

    1983-09-01

    The mean spherical approximation applied to a metal-molten salt interface is generalized to take further account of the local density profiles near the electrode. The temperature dependence of the differential capacitance is shown to arise, in large measure from such local structure. However, the hard wall assumption for the electrode is retained and this must be kept in mind in comparing our model results with experiment. (author)

  3. Application of seamless vertical profiles for use in the topside electron density modeling

    Czech Academy of Sciences Publication Activity Database

    Třísková, Ludmila; Galkin, I.; Truhlík, Vladimír; Reinisch, B. W.

    2007-01-01

    Roč. 39, č. 5 (2007), s. 774-778 ISSN 0273-1177 R&D Projects: GA AV ČR IAA300420603; GA MŠk ME 651 Grant - others:US National Science Foundation(US) 0245457 Institutional research plan: CEZ:AV0Z30420517 Keywords : Topside ionosphere * Electron density * Ionospheric model * Altitude profile Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.774, year: 2007

  4. Role of Density Profiles for the Nonlinear Propagation of Intense Laser Beam through Plasma Channel

    Directory of Open Access Journals (Sweden)

    Sonu Sen

    2014-01-01

    Full Text Available In this work role of density profiles for the nonlinear propagation of intense laser beam through plasma channel is analyzed. By employing the expression for the dielectric function of different density profile plasma, a differential equation for beamwidth parameter is derived under WKB and paraxial approximation. The laser induces modifications of the dielectric function through nonlinearities. It is found that density profiles play vital role in laser-plasma interaction studies. To have numerical appreciation of the results the propagation equation for plasma is solved using the fourth order Runge-Kutta method for the initial plane wave front of the beam, using boundary conditions. The spot size of the laser beam decreases as the beam penetrates into the plasma and significantly adds self-focusing in plasma. This causes the laser beam to become more focused by reduction of diffraction effect, which is an important phenomenon in inertial confinement fusion and also for the understanding of self-focusing of laser pulses. Numerical computations are presented and discussed in the form of graphs for typical parameters of laser-plasma interaction.

  5. Retrieval of stratospheric ozone density profiles from OSIRIS scattered sunlight observations

    Energy Technology Data Exchange (ETDEWEB)

    Von Savigny, C. H. A.

    2002-07-01

    A new satellite instrument has been developed in Canada to monitor stratospheric ozone concentrations. The Optical Spectrograph and InfraRed Imager System (OSIRIS) has played a major contribution to global change research. The OSIRIS measures ozone densities with a powerful new method based on measurements of sunlight scattered by the atmosphere. This thesis reports the first global distribution ozone measurements made during the first months of OSIRIS operation. Ozone densities were obtained through a method based on the analysis of normalized limb radiance profiles measured at wavelengths of the Chappuis-Wulf absorption bands of ozone. The OSIRIS limb radiance measurements were analyzed by recounting the non-linear Newtonian version of the Optimal Estimation coupled with the LIMBTRAN multiple scattering radiative transfer model. In August 2001, several sets of OSIRIS limb observations were acquired for the northern hemisphere. Limb scans of stratospheric ozone density profiles were shown to correlate well with current knowledge of the global morphology of ozone. Tropospheric ozone column densities were inferred from OSIRIS stratospheric ozone densities using a residual approach and the total ozone columns measured by the Total Ozone Mapping Spectrometer on the Earth Probe satellite. Tropospheric estimates were shown to correlate reasonably well with those by Fishman. Observations in the southern hemisphere were made in October 2001 in the Antarctic ozone hole region. The data showed that the OSIRIS is capable of accurately monitoring the evolution of the 3-dimensional structure of the Antarctic ozone hole. It was concluded that OSIRIS can obtain global ozone profiles with high accuracy and high vertical resolution.

  6. Line profiles of hydrogenic ions from high-temperature and high-density plasmas

    International Nuclear Information System (INIS)

    Hou Qing; Li Jianming

    1991-01-01

    Applying the Hooper's first-order theory, the authors calculate the static micro-electric field distributions in plasmas containing various multiply-charged ions. The influences of the impurity concentrations on the micro electric field distributions and on the Lyman profiles (n→1) from hydrogenic ions are analysed. Based on the optical-thin line profiles, the radiation transfer equation in sphere plasmas with various optical depths is solved. The results confirm that the opacity-broadening of the line profiles has almost no effect on the separation of Lyman β splitted peaks. Such separation is determined by electric field at which the static micro-electric field distribution has a maximum. The separation can be utilized for spatially resolved and temporally resolved density diagnostic of fusion plasmas

  7. Modeling of flame lift-off length in diesel low-temperature combustion with multi-dimensional CFD based on the flame surface density and extinction concept

    Science.gov (United States)

    Azimov, Ulugbek; Kim, Ki-Seong; Bae, Choongsik

    2010-07-01

    Low-Temperature Combustion (LTC) is becoming a promising technology for simultaneously reducing soot and NOx emissions from diesel engines. LTC regimes are evaluated by the flame lift-off length - the distance from the injector orifice to the location of hydroxyl luminescence closest to the injector in the flame jet. Various works have been dedicated to successful simulations of lifted flames of a diesel jet by use of various combustion modeling approaches. In this work, flame surface density and flamelet concepts were used to model the diesel lift-off length under LTC conditions. Numerical studies have been performed with the ECFM3Z model, n-Heptane and diesel fuels to determine the flame lift-off length and its correlation with soot formation under quiescent conditions. The numerical results showed good agreement with experimental data, which were obtained from an optically accessible constant volume chamber and presented at the Engine Combustion Network (ECN) of Sandia National Laboratories. It was shown that at a certain distance downstream from the injector orifice, stoichiometric scalar dissipation rate matched the extinction scalar dissipation rate. This computed extinction scalar dissipation rate correlated well with the flame lift-off length. For the range of conditions investigated, adequate quantitative agreement was obtained with the experimental measurements of lift-off length under various ambient gas O2 concentrations, ambient gas temperatures, ambient gas densities and fuel injection pressures. The results showed that the computed lift-off length values for most of the conditions lay in a reasonable range within the quasi-steady lift-off length values obtained from experiments. However, at ambient temperatures lower than 1000 K, the lift-off length values were under-predicted by the numerical analysis. This may be due to the use of the droplet evaporation model as it is believed that evaporation has a strong effect on the lift-off length.

  8. Influence of facial hair length, coarseness, and areal density on seal leakage of a tight-fitting half-face respirator.

    Science.gov (United States)

    Floyd, Evan L; Henry, J Blake; Johnson, David L

    2018-04-01

    OSHA regulations state that an employer shall not permit tight-fitting respirators to be worn by employees who have facial hair that comes between the skin and facepiece seal. Studies have shown that facial hair in the face seal zone can increase penetration and decrease the fit factor (FF), although the relationship between the amount and characteristics of facial hair and the increase in penetration is not well quantified. This article examines the influence of facial hair length, areal density, and coarseness on FF for one model of half-face elastomeric negative-pressure air purifying respirator. Quantitative fit tests (QNFT) were performed on 19 subjects with beards initially 0.500-in long and subsequently trimmed to 0.250, 0.125, and 0.063 in, then after a razor shave. Three fit tests were performed at each of the 5 lengths, for 285 total tests. The average diameter and areal density of cheek and chin hair were measured. Penetration was modeled as a function of hair length category, beard areal density, and hair coarseness. FF decreased with beard length, especially beyond 0.125 in. However, passing FF scores were achieved on all tests by all subjects at the smooth shave and 0.063 in conditions, and 98% of tests were passed at 0.125 in; seven subjects passed all tests at all conditions. Chin and cheek areal densities were significantly different and were only weakly correlated. Beard hair diameters were normally distributed across subjects (mean 76 µm, standard deviation 7.4 µm). Beard length and areal density, but not coarseness, were statistically significant predictors of fit using an arcsine transformed penetration model. FF decreased with increasing beard length, especially beyond 0.125 in, although FF with a "stubble" beard did not differ significantly from a smooth shave. FF also decreased with increasing areal beard hair density. Beard length and areal density negatively influence FF. However, tight-fitting half-face negative-pressure respirator

  9. TIDAL STIRRING OF SATELLITES WITH SHALLOW DENSITY PROFILES PREVENTS THEM FROM BEING TOO BIG TO FAIL

    Energy Technology Data Exchange (ETDEWEB)

    Tomozeiu, Mihai; Mayer, Lucio [Institute for Computational Science, University of Zurich, Winterthurerstrasse 190, CH-8057 Zürich (Switzerland); Quinn, Thomas, E-mail: mihai@physik.uzh.ch [Astronomy Department, University of Washington, Box 351580, Seattle, WA 98195 (United States)

    2016-08-10

    The “too big to fail” problem is revisited by studying the tidal evolution of populations of dwarf satellites with different density profiles. The high-resolution cosmological ΛCDM “ErisMod” set of simulations is used. These simulations can model both the stellar and dark matter components of the satellites, and their evolution under the action of the tides of a Milky Way (MW)-sized host halo at a force resolution better than 10 pc. The stronger tidal mass loss and re-shaping of the mass distribution induced in satellites with γ = 0.6 dark matter density distributions, as those resulting from the effect of feedback in hydrodynamical simulations of dwarf galaxy formation, are sufficient to bring the circular velocity profiles in agreement with the kinematics of MW’s dSphs. In contrast, in simulations in which the satellites retain cusps at z = 0 there are several “massive failures” with circular velocities in excess of the observational constraints. Various sources of deviations in the conventionally adopted relation between the circular velocity at the half-light radius and the one-dimensional line of sight velocity dispersions are found. Such deviations are caused by the response of circular velocity profiles to tidal effects, which also varies depending on the initially assumed inner density profile and by the complexity of the stellar kinematics, which include residual rotation and anisotropy. In addition, tidal effects naturally induce large deviations in the stellar mass–halo mass relation for halo masses below 10{sup 9} M {sub ⊙}, preventing any reliable application of the abundance matching technique to dwarf galaxy satellites.

  10. Radial Surface Density Profiles of Gas and Dust in the Debris Disk around 49 Ceti

    Energy Technology Data Exchange (ETDEWEB)

    Hughes, A. Meredith; Lieman-Sifry, Jesse; Flaherty, Kevin M.; Daley, Cail M. [Department of Astronomy, Van Vleck Observatory, Wesleyan University, 96 Foss Hill Drive, Middletown, CT 06459 (United States); Roberge, Aki [Exoplanets and Stellar Astrophysics Laboratory, NASA Goddard Space Flight Center, Code 667, Greenbelt, MD 20771 (United States); Kóspál, Ágnes; Moór, Attila; Ábrahám, Peter [Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Hungarian Academy of Sciences, P.O. Box 67, 1525 Budapest (Hungary); Kamp, Inga [Kapteyn Astronomical Institute, University of Groningen, Postbus 800, 9700 AV Groningen (Netherlands); Wilner, David J.; Andrews, Sean M. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS-51, Cambridge, MA 02138 (United States); Kastner, Joel H., E-mail: amhughes@astro.wesleyan.edu [Rochester Institute of Technology, 54 Lomb Memorial Drive, Rochester, NY 14623 (United States)

    2017-04-20

    We present ∼0.″4 resolution images of CO(3–2) and associated continuum emission from the gas-bearing debris disk around the nearby A star 49 Ceti, observed with the Atacama Large Millimeter/Submillimeter Array (ALMA). We analyze the ALMA visibilities in tandem with the broadband spectral energy distribution to measure the radial surface density profiles of dust and gas emission from the system. The dust surface density decreases with radius between ∼100 and 310 au, with a marginally significant enhancement of surface density at a radius of ∼110 au. The SED requires an inner disk of small grains in addition to the outer disk of larger grains resolved by ALMA. The gas disk exhibits a surface density profile that increases with radius, contrary to most previous spatially resolved observations of circumstellar gas disks. While ∼80% of the CO flux is well described by an axisymmetric power-law disk in Keplerian rotation about the central star, residuals at ∼20% of the peak flux exhibit a departure from axisymmetry suggestive of spiral arms or a warp in the gas disk. The radial extent of the gas disk (∼220 au) is smaller than that of the dust disk (∼300 au), consistent with recent observations of other gas-bearing debris disks. While there are so far only three broad debris disks with well characterized radial dust profiles at millimeter wavelengths, 49 Ceti’s disk shows a markedly different structure from two radially resolved gas-poor debris disks, implying that the physical processes generating and sculpting the gas and dust are fundamentally different.

  11. Modeling the kinematic effect of horizontal strain rates on firn depth-density profiles

    Science.gov (United States)

    Horlings, A. N.; Stevens, C. M.; Holschuh, N.; Christianson, K. A.; Waddington, E. D.

    2017-12-01

    Firn compaction must be considered in interpretation of satellite repeat-altimetry measurements for ice-sheet mass balance estimates that are used to determine land-ice contribution to sea-level change. Firn compaction models remain the largest source of uncertainty in determining ice-sheet mass balance from repeat altimetry because the physical processes responsible for firn compaction are not fully understood. Most commonly used firn compaction models are 1-D, empirical or semi-empirical, and built on steady-state assumptions. These assumptions may be inappropriate in some regions, particularly areas of dynamic flow. In many of these regions, the horizontal strain rate due to dynamic ice flow can be similar in magnitude to the vertical strain rate from firn compaction. Therefore, horizontal stresses are important to consider in calculating firn depth-density profiles, yet are not represented in the current generation of firn compaction models. Here, we incorporate the kinematic effect of longitudinal strain on firn depth-density profiles in the dry snow zone. In every time step, the firn first densifies and consequently thins via a firn densification model; then, the firn stretches (thins) as stipulated by an imposed longitudinal strain rate without further density changes. Idealized tests show that the kinematic effect for longitudinal strain rates larger than 10-4 yr-1 can significantly decrease the depth-integrated porosity (> 0.5m) for climatic conditions representative of northeast Greenland. For conditions common on Thwaites Glacier, West Antarctica, results indicate that the kinematic effect on the firn column can shallow the bubble close-off depth by 20m and decrease the depth-integrated porosity by 7m. These results suggest that incorporating horizontal stresses into firn compaction models is essential to accurately model firn depth-density profiles in regions of ice sheets with high horizontal strain rates.

  12. Comparison of current density profiles based on particle orbit-driven current in steady-state plasma on QUEST

    Energy Technology Data Exchange (ETDEWEB)

    Alam, Md Mahbub, E-mail: m.alam@triam.kyushu-u.ac.jp [IGSES, Kyushu University, 6-1 Kasuga-koen, Kasuga, Fukuoka 816-8580 (Japan); Nakamura, Kazuo [RIAM, Kyushu University, 6-1 Kasuga-koen, Kasuga, Fukuoka 816-8580 (Japan); Xia, Fan [CFS, SWIP, P.O. Box 432, 610041 Chengdu (China); Mitarai, Osamu [Tokai University, Kumamoto 862-8652 (Japan); Hasegawa, Makoto; Tokunaga, Kazutoshi; Araki, Kuniaki; Zushi, Hideki; Hanada, Kazuaki; Fujisawa, Akihide; Idei, Hiroshi; Nagashima, Yoshihiko; Kawasaki, Shoji; Nakashima, Hisatoshi; Higashijima, Aki; Nagata, Takahiro [RIAM, Kyushu University, 6-1 Kasuga-koen, Kasuga, Fukuoka 816-8580 (Japan)

    2016-11-01

    Highlights: • Electron cyclotron resonance heating (ECRH) of QUEST. • Particle guiding center orbit calculation. • Orbit-driven current density profile. • Hollow current density. • Equilibrium condition for steady-state operation of QUEST. - Abstract: In the present RF-driven divertor plasma of QUEST, it has been observed that orbit-driven current flows in the open magnetic surfaces outside of the closed magnetic surfaces. To observe this phenomenon and the characteristics of the orbit-driven current, current density profiles have been calculated on two different equilibrium conditions. We calculated current density profiles from particle guiding center orbits both for the fundamental and the second harmonic resonances for the 8.2 GHz electron cyclotron current drive. From this calculation, hollow current density profiles have been obtained with significant characteristics on both conditions. Only positive current distribution has been observed in the open magnetic surfaces outside of the closed magnetic surfaces.

  13. Revisiting internal gravity waves analysis using GPS RO density profiles: comparison with temperature profiles and application for wave field stability study

    Science.gov (United States)

    Pisoft, Petr; Sacha, Petr; Miksovsky, Jiri; Huszar, Peter; Scherllin-Pirscher, Barbara; Foelsche, Ulrich

    2018-01-01

    We revise selected findings regarding the utilization of Global Positioning System radio occultation (GPS RO) density profiles for the analysis of internal gravity waves (IGW), introduced by Sacha et al. (2014). Using various GPS RO datasets, we show that the differences in the IGW spectra between the dry-temperature and dry-density profiles that were described in the previous study as a general issue are in fact present in one specific data version only. The differences between perturbations in the temperature and density GPS RO profiles do not have any physical origin, and there is not the information loss of IGW activity that was suggested in Sacha et al. (2014). We investigate the previously discussed question of the temperature perturbations character when utilizing GPS RO dry-temperature profiles, derived by integration of the hydrostatic balance. Using radiosonde profiles as a proxy for GPS RO, we provide strong evidence that the differences in IGW perturbations between the real and retrieved temperature profiles (which are based on the assumption of hydrostatic balance) include a significant nonhydrostatic component that is present sporadically and might be either positive or negative. The detected differences in related spectra of IGW temperature perturbations are found to be mostly about ±10 %. The paper also presents a detailed study on the utilization of GPS RO density profiles for the characterization of the wave field stability. We have analyzed selected stability parameters derived from the density profiles together with a study of the vertical rotation of the wind direction. Regarding the Northern Hemisphere the results point to the western border of the Aleutian high, where potential IGW breaking is detected. These findings are also supported by an analysis of temperature and wind velocity profiles. Our results confirm advantages of the utilization of the density profiles for IGW analysis.

  14. Revisiting internal gravity waves analysis using GPS RO density profiles: comparison with temperature profiles and application for wave field stability study

    Directory of Open Access Journals (Sweden)

    P. Pisoft

    2018-01-01

    Full Text Available We revise selected findings regarding the utilization of Global Positioning System radio occultation (GPS RO density profiles for the analysis of internal gravity waves (IGW, introduced by Sacha et al. (2014. Using various GPS RO datasets, we show that the differences in the IGW spectra between the dry-temperature and dry-density profiles that were described in the previous study as a general issue are in fact present in one specific data version only. The differences between perturbations in the temperature and density GPS RO profiles do not have any physical origin, and there is not the information loss of IGW activity that was suggested in Sacha et al. (2014. We investigate the previously discussed question of the temperature perturbations character when utilizing GPS RO dry-temperature profiles, derived by integration of the hydrostatic balance. Using radiosonde profiles as a proxy for GPS RO, we provide strong evidence that the differences in IGW perturbations between the real and retrieved temperature profiles (which are based on the assumption of hydrostatic balance include a significant nonhydrostatic component that is present sporadically and might be either positive or negative. The detected differences in related spectra of IGW temperature perturbations are found to be mostly about ±10 %. The paper also presents a detailed study on the utilization of GPS RO density profiles for the characterization of the wave field stability. We have analyzed selected stability parameters derived from the density profiles together with a study of the vertical rotation of the wind direction. Regarding the Northern Hemisphere the results point to the western border of the Aleutian high, where potential IGW breaking is detected. These findings are also supported by an analysis of temperature and wind velocity profiles. Our results confirm advantages of the utilization of the density profiles for IGW analysis.

  15. Recent measurements of electron density profiles of plasmas in PLADIS I, a plasma disruption simulator

    International Nuclear Information System (INIS)

    Bradley, J. III; Sharp, G.; Gahl, J.M. Kuznetsov, V.; Rockett, P.; Hunter, J.

    1995-01-01

    Tokamak disruption simulation experiments are being conducted at the University of New Mexico (UNM) using the PLADIS I plasma gun system. PLADIS I is a high power, high energy coaxial plasma gun configured to produce an intense plasma beam. First wall candidate materials are placed in the beam path to determine their response under disruption relevant energy densities. An optically thick vapor shield plasma has been observed to form above the target surface in PLADIS I. Various diagnostics have been used to determine the characteristics of the incident plasma and the vapor shielding plasma. The cross sectional area of the incident plasma beam is a critical characteristic, as it is used in the calculation of the incident plasma energy density. Recently, a HeNe interferometer in the Mach-Zehnder configuration has been constructed and used to probe the electron density of the incident plasma beam and vapor shield plasma. The object beam of the interferometer is scanned across the plasma beam on successive shots, yielding line integrals of beam density on different chords through the plasma. Data from the interferometer is used to determine the electron density profile of the incident plasma beam as a function of beam radius. This data is then used to calculate the effective beam area. Estimates. of beam area, obtained from other diagnostics such as damage targets, calorimeter arrays and off-axis measurements of surface pressure, will be compared with data from the interferometer to obtain a better estimate of the beam cross sectional area

  16. Generalized saddle point condition for ignition in a tokamak reactor with temperature and density profiles

    International Nuclear Information System (INIS)

    Mitari, O.; Hirose, A.; Skarsgard, H.M.

    1989-01-01

    In this paper, the concept of a generalized ignition contour map, is extended to the realistic case of a plasma with temperature and density profiles in order to study access to ignition in a tokamak reactor. The generalized saddle point is found to lie between the Lawson and ignition conditions. If the height of the operation path with Goldston L-mode scaling is higher than the generalized saddle point, a reactor can reach ignition with this scaling for the case with no confinement degradation effect due to alpha-particle heating. In this sense, the saddle point given in a general form is a new criterion for reaching ignition. Peaking the profiles for the plasma temperature and density can lower the height of the generalized saddle point and help a reactor to reach ignition. With this in mind, the authors can judge whether next-generation tokamaks, such as Compact Ignition Tokamak, Tokamak Ignition/Burn Experimental Reactor, Next European Torus, Fusion Experimental Reactor, International Tokamak Reactor, and AC Tokamak Reactor, can reach ignition with realistic profile parameters and an L-mode scaling law

  17. Relativistic self-focusing of intense laser beam in thermal collisionless quantum plasma with ramped density profile

    Directory of Open Access Journals (Sweden)

    S. Zare

    2015-04-01

    Full Text Available Propagation of a Gaussian x-ray laser beam has been analyzed in collisionless thermal quantum plasma with considering a ramped density profile. In this density profile due to the increase in the plasma density, an earlier and stronger self-focusing effect is noticed where the beam width oscillates with higher frequency and less amplitude. Moreover, the effect of the density profile slope and the initial plasma density on the laser propagation has been studied. It is found that, by increasing the initial density and the ramp slope, the laser beam focuses faster with less oscillation amplitude, smaller laser spot size and more oscillations. Furthermore, a comparison is made among the laser self-focusing in thermal quantum plasma, cold quantum plasma and classical plasma. It is realized that the laser self-focusing in the quantum plasma becomes stronger in comparison with the classical regime.

  18. Standard Test Method for Obtaining Char Density Profile of Ablative Materials by Machining and Weighing

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1996-01-01

    1.1 This test method covers the determination of the char density profile of a charred ablator that can be used with the following limitations: 1.1.1 The local surface imperfections must be removed, and the char must be able to be machined off in a plane parallel to the char-virgin material interface before the density profiles can be determined. 1.1.2 The char must be strong enough to withstand the machining and handling techniques employed. 1.1.3 The material should have orderly density variations. The total thickness of the char and degradation zone must be larger than the machining thicknesses required. 1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.2.1 Exception—Certain inch-pound equivalent units are included in parentheses for information only. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establis...

  19. Effect of plasma density profile of tokamak on Kelvin-Helmholtz instability

    International Nuclear Information System (INIS)

    Tang Fulin

    1984-01-01

    The purpose of this paper is to study the effect of radial distribution of plasma density profile of tokamak on Kelvin-Helmholtz instability caused by toroidal rotation. The effect of radial distribution of plasma rotational velocity on stability is also examine for comparison. It is found that within the range of tokamak parameters the only radial distribution of plasma rotational velocity cannot induce Kelvin-Helmholtz instability. On the contrary, when there is a radial distribution of plasma density, i.e. P 01 =P 0 e -tx and V 0 1 = const, plasma becomes unstable, and instability will increase proportionally to the value of t. Meanwhile when the value of t remains constant, the instability growth rate will decrease if P 0 grows or the distance between plasma and wall of container decreases too. It shows that the Kelvin-Helmoltz instability is not only influenced by the steepness of density profile but also by the inertia of plasma in central region, which is helpful for depressing the instability. (author). 5 refs, 4 figs, 2 tabs

  20. Fluid and gyrokinetic modelling of particle transport in plasmas with hollow density profiles

    International Nuclear Information System (INIS)

    Tegnered, D; Oberparleiter, M; Nordman, H; Strand, P

    2016-01-01

    Hollow density profiles occur in connection with pellet fuelling and L to H transitions. A positive density gradient could potentially stabilize the turbulence or change the relation between convective and diffusive fluxes, thereby reducing the turbulent transport of particles towards the center, making the fuelling scheme inefficient. In the present work, the particle transport driven by ITG/TE mode turbulence in regions of hollow density profiles is studied by fluid as well as gyrokinetic simulations. The fluid model used, an extended version of the Weiland transport model, Extended Drift Wave Model (EDWM), incorporates an arbitrary number of ion species in a multi-fluid description, and an extended wavelength spectrum. The fluid model, which is fast and hence suitable for use in predictive simulations, is compared to gyrokinetic simulations using the code GENE. Typical tokamak parameters are used based on the Cyclone Base Case. Parameter scans in key plasma parameters like plasma β, R/L T , and magnetic shear are investigated. It is found that β in particular has a stabilizing effect in the negative R/L n region, both nonlinear GENE and EDWM show a decrease in inward flux for negative R/L n and a change of direction from inward to outward for positive R/L n . This might have serious consequences for pellet fuelling of high β plasmas. (paper)

  1. Constraining the Milky Way dark matter density profile with gamma-rays with Fermi-LAT

    International Nuclear Information System (INIS)

    Bernal, Nicolás; Palomares-Ruiz, Sergio

    2012-01-01

    We study the abilities of the Fermi-LAT instrument on board of the Fermi mission to simultaneously constrain the Milky Way dark matter density profile and some dark matter particle properties, as annihilation cross section, mass and branching ratio into dominant annihilation channels. A single dark matter density profile is commonly assumed to determine the capabilities of gamma-ray experiments to extract dark matter properties or to set limits on them. However, our knowledge of the Milky Way halo is far from perfect, and thus in general, the obtained results are too optimistic. Here, we study the effect these astrophysical uncertainties would have on the determination of dark matter particle properties and conversely, we show how gamma-ray searches could also be used to learn about the structure of the Milky Way halo, as a complementary tool to other type of observational data that study the gravitational effect caused by the presence of dark matter. In addition, we also show how these results would improve if external information on the annihilation cross section and on the local dark matter density were included and compare our results with the predictions from numerical simulations

  2. On the scattering length density of proteins in H2O/D2O. Determination of H-D exchange using ES+I-MS

    International Nuclear Information System (INIS)

    Efimova, Y.M.; Wierczinski, B.; Well, A.A. Van; Bouwman, W.G.; Hanefeld, U.

    2005-01-01

    Neutron reflectometry is an excellent technique to determine the structure of a protein layer adsorbed at a solid interface. The use of contrast-variation makes it possible to highlight the adsorbed protein layer. The neutron scattering lengths of D and H have opposite signs. By choosing the H 2 O/D 2 O ratio, the scattering length density can be made equal to that of the adsorbing substrate. To determine the scattering length density of protein, both its volume and its scattering length in solution is needed. To calculate the scattering length, the H-D exchange of the labile protons of the protein should be taken into account. For monitoring the H-D exchange, electrospray ionization mass spectroscopy (ES + I-MS) was applied. It is shown that ES + I-MS is the appropriate technique for quantitative analysis of the H-D exchange. Experimental results for the exchange in lysozyme and β-casein with theoretical calculations are compared. (author)

  3. Iterative noise removal from temperature and density profiles in the TJ-II Thomson scattering

    International Nuclear Information System (INIS)

    Farias, G.; Dormido-Canto, S.; Vega, J.; Santos, M.; Pastor, I.; Fingerhuth, S.; Ascencio, J.

    2014-01-01

    TJ-II Thomson Scattering diagnostic provides temperature and density profiles of plasma. The CCD camera acquires images that are corrupted with some kind of noise called stray-light. This noise degrades both image contrast and measurement accuracy, which could produce unreliable profiles of the diagnostic. So far, several approaches have been applied in order to decrease the noise in the TJ-II Thomson scattering images. Since the presence of the noise is not global but located in some particular regions of the image, advanced processing techniques are needed. However such methods require of manual fine-tuning of parameters to reach a good performance. In this contribution, an iterative image processing approach is applied in order to reduce the stray light effects in the images of the TJ-II Thomson scattering diagnostic. The proposed solution describes how the noise can be iteratively reduced in the images when a key parameter is automatically adjusted during the iterative process

  4. Iterative noise removal from temperature and density profiles in the TJ-II Thomson scattering

    Energy Technology Data Exchange (ETDEWEB)

    Farias, G., E-mail: gonzalo.farias@ucv.cl [Pontificia Universidad Católica de Valparaíso, Av. Brasil 2147, Valparaíso (Chile); Dormido-Canto, S., E-mail: sebas@dia.uned.es [Departamento de Informática y Automática, UNED, 28040 Madrid (Spain); Vega, J., E-mail: jesus.vega@ciemat.es [Asociación EURATOM/CIEMAT para Fusión, Avd. Complutense 22, 28040 Madrid (Spain); Santos, M., E-mail: msantos@ucm.es [Departamento de Arquitectura de Computadores y Automática, Universidad Complutense de Madrid, 28040 Madrid (Spain); Pastor, I., E-mail: ignacio.pastor@ciemat.es [Asociación EURATOM/CIEMAT para Fusión, Avd. Complutense 22, 28040 Madrid (Spain); Fingerhuth, S., E-mail: sebastian.fingerhuth@ucv.cl [Pontificia Universidad Católica de Valparaíso, Av. Brasil 2147, Valparaíso (Chile); Ascencio, J., E-mail: j_ascencio21@hotmail.com [Pontificia Universidad Católica de Valparaíso, Av. Brasil 2147, Valparaíso (Chile)

    2014-05-15

    TJ-II Thomson Scattering diagnostic provides temperature and density profiles of plasma. The CCD camera acquires images that are corrupted with some kind of noise called stray-light. This noise degrades both image contrast and measurement accuracy, which could produce unreliable profiles of the diagnostic. So far, several approaches have been applied in order to decrease the noise in the TJ-II Thomson scattering images. Since the presence of the noise is not global but located in some particular regions of the image, advanced processing techniques are needed. However such methods require of manual fine-tuning of parameters to reach a good performance. In this contribution, an iterative image processing approach is applied in order to reduce the stray light effects in the images of the TJ-II Thomson scattering diagnostic. The proposed solution describes how the noise can be iteratively reduced in the images when a key parameter is automatically adjusted during the iterative process.

  5. Density profiles of granular gases studied by molecular dynamics and Brownian bridges

    Science.gov (United States)

    Peñuñuri, F.; Montoya, J. A.; Carvente, O.

    2018-02-01

    Despite the inherent frictional forces and dissipative collisions, confined granular matter can be regarded as a system in a stationary state if we inject energy continuously. Under these conditions, both the density and the granular temperature are, in general, non-monotonic variables along the height of the container. In consequence, an analytical description of a granular system is hard to conceive. Here, by using molecular dynamics simulations, we measure the packing fraction profiles for a vertically vibrating three-dimensional granular system in several gaseous-like stationary states. We show that by using the Brownian bridge concept, the determined packing fraction profiles can be reproduced accurately and give a complete description of the distribution of the particles inside the simulation box.

  6. On the choice of lens density profile in time delay cosmography

    Science.gov (United States)

    Sonnenfeld, Alessandro

    2018-03-01

    Time delay lensing is a mature and competitive cosmological probe. However, it is limited in accuracy by the well-known problem of the mass-sheet degeneracy: too rigid assumptions on the density profile of the lens can potentially bias the inference on cosmological parameters. I investigate the degeneracy between the choice of the lens density profile and the inference on the Hubble constant, focusing on double image systems. By expanding lensing observables in terms of the local derivatives of the lens potential around the Einstein radius, and assuming circular symmetry, I show that 3 degrees of freedom in the radial direction are necessary to achieve a few per cent accuracy in the time-delay distance. Additionally, while the time delay is strongly dependent on the second derivative of the potential, observables typically used to constrain lens models in time-delay studies, such as image position and radial magnification information, are mostly sensitive to the first and third derivatives, making it very challenging to accurately determine time-delay distances with lensing data alone. Tests on mock observations show that the assumption of a power-law density profile results in a 5 per cent average bias on H0, with a 6 per cent scatter. Using a more flexible model and adding unbiased velocity dispersion constraints allows me to obtain an inference with 1 per cent accuracy. A power-law model can still provide 3 per cent accuracy if velocity dispersion measurements are used to constrain its slope. Although this study is based on the assumption of axisymmetry, its main findings can be generalized to cases with moderate ellipticity.

  7. Near-Infrared Properties of Moderate-Redshift Galaxy Clusters: Luminosity Functions and Density Profiles

    Science.gov (United States)

    Muzzin, Adam; Yee, H. K. C.; Hall, Patrick B.; Ellingson, E.; Lin, H.

    2007-04-01

    We present K-band imaging for 15 of the CNOC1 clusters. The extensive spectroscopic data set available for these clusters allows us to determine the cluster K-band luminosity function and density profile without the need for statistical background subtraction. The luminosity density and number density profiles can be described by NFW models with concentration parameters of cl=4.28+/-0.70 and cg=4.13+/-0.57, respectively. Comparing these to the dynamical mass analysis of the same clusters shows that they are similar to the cluster dark matter profile. The luminosity functions show that the evolution of K* over the redshift range 0.2cluster galaxies form at high redshift (zf>1.5) and evolve passively thereafter. The best fit for the faint-end slope of the luminosity function is α=-0.84+/-0.08, which indicates that it does not evolve between z=0 and 0.3. Using principal component analysis of the spectra, we classify cluster galaxies as either star-forming/recently star-forming (EM+BAL) or non-star-forming (ELL) and compute their respective luminosity functions. The faint-end slope of the ELL luminosity function is much shallower than for the EM+BAL galaxies at z=0.3 and suggests that the number of faint ELL galaxies in clusters decreases by a factor of ~3 from z=0 to 0.3. The redshift evolution of K* for both EM+BAL and ELL types is consistent with a passively evolving stellar population formed at high redshift. Passive evolution in both classes demonstrates that the bulk of the stellar population in all bright cluster galaxies is formed at high redshift, and subsequent transformations in morphology/color/spectral type have little effect on the total stellar mass.

  8. Near-Infrared Properties of Moderate-Redshift Galaxy Clusters: Luminosity Functions and Density Profiles

    Energy Technology Data Exchange (ETDEWEB)

    Muzzin, Adam; Yee, H.K.C.; /Toronto U., Astron. Dept.; Hall, Patrick B.; /York U., Canada; Ellingson, E.; /Colorado U., CASA; Lin, Huan; /Fermilab

    2006-12-01

    We present K-band imaging for 15 of the Canadian Network for Observational Cosmology (CNOC1) clusters. The extensive spectroscopic dataset available for these clusters allows us to determine the cluster K-band luminosity function and density profile without the need for statistical background subtraction. The luminosity density and number density profiles can be described by NFW models with concentration parameters of c{sub l} = 4.28 {+-} 0.70 and c{sub g} = 4.13 {+-} 0.57 respectively. Comparing these to the dynamical mass analysis of the same clusters shows that the galaxy luminosity and number density profiles are similar to the dark matter profile, and are not less concentrated like in local clusters. The luminosity functions show that the evolution of K. over the redshift range 0.2 < z < 0.5 is consistent with a scenario where the majority of stars in cluster galaxies form at high-redshift (z{sub f} > 1.5) and evolve passively thereafter. The best-fit for the faint-end slope of the luminosity function is {alpha} = -0.84 {+-} 0.08, which indicates that it does not evolve between z = 0 and z = 0.3. Using Principal Component Analysis of the spectra we classify cluster galaxies as either star-forming/recently-star-forming (EM+BAL) or non-star forming (ELL) and compute their respective luminosity functions. The faint-end slope of the ELL luminosity function is much shallower than for the EM+BAL galaxies at z = 0.3, and suggests the number of faint ELL galaxies in clusters decreases by a factor of {approx} 3 from z = 0 to z = 0.3. The redshift evolution of K* for both EM+BAL and ELL types is consistent with a passively evolving stellar population formed at high-redshift. Passive evolution in both classes, as well as the total cluster luminosity function, demonstrates that the bulk of the stellar population in all bright cluster galaxies is formed at high-redshift and subsequent transformations in morphology/color/spectral-type have little effect on the total stellar

  9. Simple neutral density profile calculation for tokamaks with lambda/sub mfp/<

    International Nuclear Information System (INIS)

    Goldston, R.J.

    1978-05-01

    A simple and expeditious technique is developed for calculating the neutral density profile in the dense region of large tokamak plasmas, where lambda/sub mfp/ much less than a. The method rests on determining the local logarithmic derivative of n 0 from a self-consistent calculation of the radial flux of neutrals, GAMMA, combined with the condition that NABLA . GAMMA = n 0 n/sub e/ (sigma v)/sub ei/. The results from this simple technique are compared with a more time-consuming Monte-Carlo calculaion, and good agreement is found

  10. A simple neutral density profile calculation for Tokamaks with lambdasub(mfp) << a

    International Nuclear Information System (INIS)

    Goldston, R.J.

    1978-01-01

    A simple and expeditious technique is developed for calculating the neutral density profile in the dense region of large Tokamak plasmas, where lambdasub(mfp) << a. The method rests on determining the local logarithmic derivative of nsub(o) from a self-consistent calculation of the radial flux of neutrals GAMMA, combined with the condition that Del.GAMMA +nsub(o)nsub(e)(σν)sub(ei) = 0. The results from this simple technique are compared with a more time-consuming Monte-Carlo calculation, and good agreement is found. (author)

  11. Measurements of electron density and temperature profiles in a gas blanket experiment

    International Nuclear Information System (INIS)

    Kuthy, A.

    1979-02-01

    Radial profiles of electron density, temperature and H sub(β) intensity are presented for the rotating plasma device F-1. The hydrogen filling pressure, the average magnetic field strength at the midplane, and the power input to the discharge have been varied in the ranges 10-100 mTorr, 0.25-0.5 Tesla, and 0.1 to 1.5 MW, respectively. These experiments have been performed with the main purpose of studying the gas blanket (cold-mantle) state of the plasma. It is shown, that a simple spectroscopic method can be used to derive the radial distribution of the electron temperature in such plasmas. The observed peak temperatures and densities are in agreement with earlier theoretical estimates. (author)

  12. Fast-scan monitor examines neutral-beam ion-density profile

    International Nuclear Information System (INIS)

    Anon.

    1978-01-01

    All of the magnetic mirror confinement fusion experiments at LLL and at other laboratories depend on pulsed, energetic neutral-beam injection for fueling and imparting energy to the trapped plasma for density build-up and stability studies. It is vital to be able to monitor how well the injected ion beam is aimed and focused. To do this, we have designed an ion-beam current-density profile monitor that uses a commercial minimodular data acquisition system. Our prototype model monitors a single 20-kV, 50-A, 10-ms beam. However, the method is applicable to any number of beams with similar sampling target arrays. Also, the electronics can be switched to monitor any one of several target collectors

  13. Specific Modulus and Density Profile as Characterization Criteria of Prefabricated Wood Composite Materials

    Directory of Open Access Journals (Sweden)

    Pavel Král

    2015-01-01

    Full Text Available Wood based product industry has developed and modified a wide range of products to cater changing demands of construction industry. Development of a product necessitates characterization to ensure compliance to established standards. Traditionally a product was characterized by properties like bending properties, density and swelling factor etc. Whereas, advances in technology has introduced more sophisticated parameters which represent a combination of various classical factors and provide more practical and detailed information. In this study, we procured four different types of commercial products, viz. Gypsum board, cement board, oriented strand board and gypsum fiber board and tried to characterized them using density profile ratio and stiffness ratio. We observed some interesting empirical relations between various parameters as represented in various plots.

  14. Density profiles and collective excitations of a trapped two-component Fermi vapour

    International Nuclear Information System (INIS)

    Amoruso, M.; Meccoli, I.; Minguzzi, A.; Tosi, M.P.

    1999-08-01

    We discuss the ground state and the small-amplitude excitations of a degenerate vapour of fermionic atoms placed in two hyperfine states inside a spherical harmonic trap. An equations-of-motion approach is set up to discuss the hydrodynamic dissipation processes from the interactions between the two components of the fluid beyond mean-field theory and to emphasize analogies with spin dynamics and spin diffusion in a homogeneous Fermi liquid. The conditions for the establishment of a collisional regime via scattering against cold-atom impurities are analyzed. The equilibrium density profiles are then calculated for a two-component vapour of 40 K atoms: they are little modified by the interactions for presently relevant values of the system parameters, but spatial separation of the two components will spontaneously arise as the number of atoms in the trap is increased. The eigenmodes of collective oscillation in both the total particle number density and the concentration density are evaluated analytically in the special case of a symmetric two-component vapour in the collisional regime. The dispersion relation of the surface modes for the total particle density reduces in this case to that of a one-component Fermi vapour, whereas the frequencies of all other modes are shifted by the interactions. (author)

  15. On Lowering the Error Floor of Short-to-Medium Block Length Irregular Low Density Parity Check Codes

    OpenAIRE

    Abdu-Aguye, Umar-Faruk

    2018-01-01

    Edited version embargoed until 22.03.2019 Full version: Access restricted permanently due to 3rd party copyright restrictions. Restriction set on 22.03.2018 by SE, Doctoral College Gallager proposed and developed low density parity check (LDPC) codes in the early 1960s. LDPC codes were rediscovered in the early 1990s and shown to be capacity approaching over the additive white Gaussian noise (AWGN) channel. Subsequently, density evolution (DE) optimized symbol node degree distributions ...

  16. Aluminum integral foams with tailored density profile by adapted blowing agents

    Science.gov (United States)

    Hartmann, Johannes; Fiegl, Tobias; Körner, Carolin

    2014-05-01

    The goal of the present work is the variation of the structure of aluminum integral foams regarding the thickness of the integral solid skin as well as the density profile. A modified die casting process, namely integral foam molding, is used in which an aluminum melt and blowing agent particles (magnesium hydride MgH2) are injected in a permanent steel mold. The high solidification rates at the cooled walls of the mold lead to the formation of a solid skin. In the inner region, hydrogen is released by thermal decomposition of MgH2 particles. Thus, the pore formation takes place parallel to the continuing solidification of the melt. The thickness of the solid skin and the density profile of the core strongly depend on the interplay between solidification velocity and kinetics of hydrogen release. By varying the melt and blowing agent properties, the structure of integral foams can be systematically changed to meet the requirements of the desired field of application of the produced component.

  17. Influence of screw length and diameter on tibial strain energy density distribution after anterior cruciate ligament reconstruction

    Science.gov (United States)

    Yao, Jie; Kuang, Guan-Ming; Wong, Duo Wai-Chi; Niu, Wen-Xin; Zhang, Ming; Fan, Yu-Bo

    2014-04-01

    Postoperative tunnel enlargement has been frequently reported after anterior cruciate ligament (ACL) reconstruction. Interference screw, as a surgical implant in ACL reconstruction, may influence natural loading transmission and contribute to tunnel enlargement. The aims of this study are (1) to quantify the alteration of strain energy den sity (SED) distribution after the anatomic single-bundle ACL reconstruction; and (2) to characterize the influence of screw length and diameter on the degree of the SED alteration. A validated finite element model of human knee joint was used. The screw length ranging from 20 to 30mm with screw diameter ranging from 7 to 9 mm were investigated. In the post-operative knee, the SED increased steeply at the extra-articular tunnel aperture under compressive and complex loadings, whereas the SED decreased beneath the screw shaft and nearby the intra-articular tunnel aperture. Increasing the screw length could lower the SED deprivation in the proximal part of the bone tunnel; whereas increasing either screw length or diameter could aggravate the SED deprivation in the distal part of the bone tunnel. Decreasing the elastic modulus of the screw could lower the bone SED deprivation around the screw. In consideration of both graft stability and SED alteration, a biodegradable interference screw with a long length is recommended, which could provide a beneficial mechanical environment at the distal part of the tunnel, and meanwhile decrease the bone-graft motion and synovial fluid propagation at the proximal part of the tunnel. These findings together with the clinical and histological factors could help to improve surgical outcome, and serve as a preliminary knowledge for the following study of biodegradable interference screw. [Figure not available: see fulltext.

  18. A Simultaneous Density-Integral System for Estimating Stem Profile and Biomass: Slash Pine and Willow Oak

    Science.gov (United States)

    Bernard R. Parresol; Charles E. Thomas

    1996-01-01

    In the wood utilization industry, both stem profile and biomass are important quantities. The two have traditionally been estimated separately. The introduction of a density-integral method allows for coincident estimation of stem profile and biomass, based on the calculus of mass theory, and provides an alternative to weight-ratio methodology. In the initial...

  19. Effects of volcano profile on dilute pyroclastic density currents: Numerical simulations

    Science.gov (United States)

    Doronzo, D. M.; Valentine, G. A.; Dellino, P.; de Tullio, M. D.

    2012-04-01

    Explosive activity and lava dome collapse at stratovolcanoes can lead to pyroclastic density currents (PDCs; mixtures of volcanic gas, air, and volcanic particles) that produce complex deposits and pose a hazard to surrounding populations. Two-dimensional numerical simulations of dilute PDCs (characterized by a turbulent suspended load and deposition through a bed load) are carried out with the Euler-Lagrange approach of multiphase physics. The fluid phase is modeled as a dusty gas (1.88 kg/m3 dense), and the solid phase is modeled as discrete particles (1 mm, 5 mm, and 10 mm; 1500 kg/m3 dense and irregularly-shaped), which are two-way coupled to the gas, i.e. they affect the fluid turbulence. The initial PDC, which enters a volcano domain 5 km long and 1.9 km high, has the following characteristics: thickness of 200 m, velocity of 20 m/s, temperature of 573 K, turbulence of 5 %, and sediment concentration of 3 % by volume. The actual physics of flow boundary zone is simulated at the PDC base, by monitoring the sediment flux toward the substrate, which acts through the flow boundary zone, and the grain-size distribution. Also, the PDC velocity and dynamic pressure are calculated. The simulations show that PDC transport, deposition, and hazard potential are sensitive to the shape of the volcano slope (profile) down which they flow. In particular, three generic volcano profiles, straight, concave-upward, and convex-upward are focused on. Dilute PDCs that flow down a constant slope gradually decelerate over the simulated run-out distance (5 km in the horizontal direction) due to a combination of sedimentation, which reduces the density of the PDC, and mixing with the atmosphere. However, dilute PDCs down a concave-upward slope accelerate high on the volcano flanks and have less sedimentation until they begin to decelerate over the shallow lower slopes. A convex-upward slope causes dilute PDCs to lose relatively more of their pyroclast load on the upper slopes of a

  20. Density and length of stomatal and epidermal cells in "living fossil" trees grown under elevated CO 2 and a polar light regime

    Science.gov (United States)

    Ogaya, R.; Llorens, L.; Peñuelas, J.

    2011-07-01

    During the Cretaceous and early Tertiary, when the climate was warm and the atmospheric CO 2 concentration ([CO 2]) was at least double that of the present-day, polar forests populated high latitude landmasses. We investigated the density and length of stomata and other epidermal cells of two deciduous and three evergreen "living fossil" tree species representative of these ancient forests. These tree species were grown in a simulated Cretaceous high latitude environment at either ambient (400 ppmv) or elevated (800 ppmv) [CO 2] during four years. After 4 years growing at elevated [CO 2], the leaf stomatal density and index (percentage of leaf epidermal cells that are stomata) of these plants were similar to those of their counterparts growing at ambient [CO 2]. While the CO 2 enrichment only modified the stomatal pore length in two of the five studied species, it increased significantly the overall length of the epidermal cells of all the species, reducing their density. These results revealed that leaf epidermal cells of these "living fossil" species were more sensitive than stomata to an experimental doubling of atmospheric CO 2 concentration.

  1. X mode reflectometry for edge density profile measurements on Tore Supra

    International Nuclear Information System (INIS)

    Clairet, F.; Bottereau, C.; Chareau, J.M.; Paume, M.; Sabot, R.

    1999-01-01

    X mode heterodyne reflectometry associated with fast sweep capabilities demonstrates very precise measurement on Tore Supra and a high sensitivity (∼10 17 m -3 ) to density variations. Very good agreement with Thomson scattering measurement is observed. Fluctuations of the radial positions of the profile are no more than ± 0.5 cm. However, edge magnetic field ripple can be a concern since it is not easy to stand precisely for the wave trajectory into the plasma and for the toroidal position of the cutoff layer; nevertheless if the error can be estimated to be less than than 3 cm in the position of the whole profile, addition work is needed combining 3-D ray tracing and different antenna systems. Additional LH heating generates an ECE noise in the same frequency range of the reflectometer and is detected. This emission throughout the plasma is fortunately stopped by the upper X mode cutoff and is also reabsorbed by the electron cyclotron resonance. But at the very edge, due to a misalignment of the antenna to the plasma magnetic field and the low optical thickness of the plasma, the first cutoff frequency, i.e. the profile initialization, may be determined less precisely. (authors)

  2. Simulating the Effects of the Airborne Lidar Scanning Angle, Flying Altitude, and Pulse Density for Forest Foliage Profile Retrieval

    Directory of Open Access Journals (Sweden)

    Haiming Qin

    2017-07-01

    Full Text Available Foliage profile is a key biophysical parameter for forests. Airborne Light Detection and Ranging is an effective tool for vegetation parameter retrieval. Data acquisition conditions influence the estimation of biophysical parameters. To acquire accurate foliage profiles at the lowest cost, we used simulations to explore the effects of data acquisition conditions on forest foliage profile retrieval. First, a 3-D forest scene and the airborne small-footprint full-waveform LiDAR data were simulated by the DART model. Second, the foliage profile was estimated from LiDAR data based on a Geometric Optical and Radiative Transfer model. Lastly, the effects of the airborne LiDAR scanning angle, flying altitude, and pulse density on foliage profile retrieval were explored. The results indicated that the scanning angle was an important factor in the foliage profile retrieval, and the optimal scanning angle was 20°. The optimal scanning angle was independent of flying altitude and pulse density, and combinations of multiple scanning angles could improve the accuracy of the foliage profile estimation. The flying altitude and pulse density had little influence on foliage profile retrieval at plot level and could be ignored. In general, our study provides reliable information for selecting the optimal instrument operational parameters to acquire more accurate foliage profiles and minimize data acquisition costs.

  3. Constraining Saturn's interior density profile from precision gravity field measurement obtained during Grand Finale

    Science.gov (United States)

    Movshovitz, N.; Fortney, J. J.; Helled, R.; Hubbard, W. B.; Mankovich, C.; Thorngren, D.; Wahl, S. M.; Militzer, B.; Durante, D.

    2017-12-01

    The external gravity field of a planetary body is determined by the distribution of mass in its interior. Therefore, a measurement of the external field, properlyinterpreted, tells us about the interior density profile, ρ(r), which in turn can be used to constrain the composition in the interior and thereby learn about theformation mechanism of the planet. Recently, very high precision measurements of the gravity coefficients for Saturn have been made by the radio science instrument on the Cassini spacecraft during its Grand Finale orbits. The resulting coefficients come with an associated uncertainty. The task of matching a given density profile to a given set of gravity coefficients is relatively straightforward, but the question of how to best account for the uncertainty is not. In essentially all prior work on matching models to gravity field data inferences about planetary structure have rested on assumptions regarding the imperfectly known H/He equation of state and the assumption of an adiabatic interior. Here we wish to vastly expand the phase space of such calculations. We present a framework for describing all the possible interior density structures of a Jovian planet constrained by a given set of gravity coefficients and their associated uncertainties. Our approach is statistical. We produce a random sample of ρ(a) curves drawn from the underlying (and unknown) probability distribution of all curves, where ρ is the density on an interior level surface with equatorial radius a. Since the resulting set of density curves is a random sample, that is, curves appear with frequency proportional to the likelihood of their being consistent with the measured gravity, we can compute probability distributions for any quantity that is a function of ρ, such as central pressure, oblateness, core mass and radius, etc. Our approach is also Bayesian, in that it can utilize any prior assumptions about the planet's interior, as necessary, without being overly

  4. Constraining the interior density profile of a Jovian planet from precision gravity field data

    Science.gov (United States)

    Movshovitz, Naor; Fortney, Jonathan J.; Helled, Ravit; Hubbard, William B.; Thorngren, Daniel; Mankovich, Chris; Wahl, Sean; Militzer, Burkhard; Durante, Daniele

    2017-10-01

    The external gravity field of a planetary body is determined by the distribution of mass in its interior. Therefore, a measurement of the external field, properly interpreted, tells us about the interior density profile, ρ(r), which in turn can be used to constrain the composition in the interior and thereby learn about the formation mechanism of the planet. Planetary gravity fields are usually described by the coefficients in an expansion of the gravitational potential. Recently, high precision measurements of these coefficients for Jupiter and Saturn have been made by the radio science instruments on the Juno and Cassini spacecraft, respectively.The resulting coefficients come with an associated uncertainty. And while the task of matching a given density profile with a given set of gravity coefficients is relatively straightforward, the question of how best to account for the uncertainty is not. In essentially all prior work on matching models to gravity field data, inferences about planetary structure have rested on imperfect knowledge of the H/He equation of state and on the assumption of an adiabatic interior. Here we wish to vastly expand the phase space of such calculations. We present a framework for describing all the possible interior density structures of a Jovian planet, constrained only by a given set of gravity coefficients and their associated uncertainties. Our approach is statistical. We produce a random sample of ρ(a) curves drawn from the underlying (and unknown) probability distribution of all curves, where ρ is the density on an interior level surface with equatorial radius a. Since the resulting set of density curves is a random sample, that is, curves appear with frequency proportional to the likelihood of their being consistent with the measured gravity, we can compute probability distributions for any quantity that is a function of ρ, such as central pressure, oblateness, core mass and radius, etc. Our approach is also bayesian, in that

  5. Emission spectra from super-critical rippled plasma density profiles illuminated by intense laser pulses

    International Nuclear Information System (INIS)

    Ondarza R, R.; Boyd, T.J.M.

    2000-01-01

    High-order harmonic emission from the interaction of intense femtosecond laser pulses with super-critical plasmas characterized by a rippled density profile at the vacuum-plasma interface has been observed from particle-in-cell (PIC) simulations. A plasma simulation box several laser wavelengths in extent was prepared with a rippled density of a fraction of a laser wavelength. Emission spectra at the very initial stage of the interaction were recorded with spectral characteristics dissimilar to those previously reported in the literature. The reflected light spectra were characterized by a strong emission at the plasma line and by a series of harmonics at multiples of the ripple frequency. Harmonic spectra were obtained for different values of the plasma ripple frequency. In all cases the harmonics were emitted at the precise multiple harmonic number of the ripple frequency. Another important feature apparent from the simulations was that the emission peaks appeared to havea complex structure as compared with those for unrippled plasmas. For the cases when the plasma was rippled the peaks that corresponded to the multiples of the rippled density typically showed a double peak for the first few harmonics. The reflected emission plots for the main laser pulse showed strong emission at the plasma frequency and at multiples of that frequency as reported by the authors in the literature. (Author)

  6. Determination of CT number and density profile of binderless, pre-treated and tannin-based Rhizophora spp. particleboards using computed tomography imaging and electron density phantom

    Energy Technology Data Exchange (ETDEWEB)

    Yusof, Mohd Fahmi Mohd, E-mail: mfahmi@usm.my; Hamid, Puteri Nor Khatijah Abdul; Tajuddin, Abdul Aziz [School of Physics, Universiti Sains Malaysia, 11800 Penang (Malaysia); Bauk, Sabar [School of Distance Education, Universiti Sains Malaysia, 11800 Penang (Malaysia); Hashim, Rokiah [School of Industrial Technologies, Universiti Sains Malaysia, 11800 Penang (Malaysia)

    2015-04-29

    Plug density phantoms were constructed in accordance to CT density phantom model 062M CIRS using binderless, pre-treated and tannin-based Rhizophora Spp. particleboards. The Rhizophora Spp. plug phantoms were scanned along with the CT density phantom using Siemens Somatom Definition AS CT scanner at three CT energies of 80, 120 and 140 kVp. 15 slices of images with 1.0 mm thickness each were taken from the central axis of CT density phantom for CT number and CT density profile analysis. The values were compared to water substitute plug phantom from the CT density phantom. The tannin-based Rhizophora Spp. gave the nearest value of CT number to water substitute at 80 and 120 kVp CT energies with χ{sup 2} value of 0.011 and 0.014 respectively while the binderless Rhizphora Spp. gave the nearest CT number to water substitute at 140 kVp CT energy with χ{sup 2} value of 0.023. The tannin-based Rhizophora Spp. gave the nearest CT density profile to water substitute at all CT energies. This study indicated the suitability of Rhizophora Spp. particleboard as phantom material for the use in CT imaging studies.

  7. Determination of CT number and density profile of binderless, pre-treated and tannin-based Rhizophora spp. particleboards using computed tomography imaging and electron density phantom

    Science.gov (United States)

    Yusof, Mohd Fahmi Mohd; Hamid, Puteri Nor Khatijah Abdul; Bauk, Sabar; Hashim, Rokiah; Tajuddin, Abdul Aziz

    2015-04-01

    Plug density phantoms were constructed in accordance to CT density phantom model 062M CIRS using binderless, pre-treated and tannin-based Rhizophora Spp. particleboards. The Rhizophora Spp. plug phantoms were scanned along with the CT density phantom using Siemens Somatom Definition AS CT scanner at three CT energies of 80, 120 and 140 kVp. 15 slices of images with 1.0 mm thickness each were taken from the central axis of CT density phantom for CT number and CT density profile analysis. The values were compared to water substitute plug phantom from the CT density phantom. The tannin-based Rhizophora Spp. gave the nearest value of CT number to water substitute at 80 and 120 kVp CT energies with χ2 value of 0.011 and 0.014 respectively while the binderless Rhizphora Spp. gave the nearest CT number to water substitute at 140 kVp CT energy with χ2 value of 0.023. The tannin-based Rhizophora Spp. gave the nearest CT density profile to water substitute at all CT energies. This study indicated the suitability of Rhizophora Spp. particleboard as phantom material for the use in CT imaging studies.

  8. Determination of CT number and density profile of binderless, pre-treated and tannin-based Rhizophora spp. particleboards using computed tomography imaging and electron density phantom

    International Nuclear Information System (INIS)

    Yusof, Mohd Fahmi Mohd; Hamid, Puteri Nor Khatijah Abdul; Tajuddin, Abdul Aziz; Bauk, Sabar; Hashim, Rokiah

    2015-01-01

    Plug density phantoms were constructed in accordance to CT density phantom model 062M CIRS using binderless, pre-treated and tannin-based Rhizophora Spp. particleboards. The Rhizophora Spp. plug phantoms were scanned along with the CT density phantom using Siemens Somatom Definition AS CT scanner at three CT energies of 80, 120 and 140 kVp. 15 slices of images with 1.0 mm thickness each were taken from the central axis of CT density phantom for CT number and CT density profile analysis. The values were compared to water substitute plug phantom from the CT density phantom. The tannin-based Rhizophora Spp. gave the nearest value of CT number to water substitute at 80 and 120 kVp CT energies with χ 2 value of 0.011 and 0.014 respectively while the binderless Rhizphora Spp. gave the nearest CT number to water substitute at 140 kVp CT energy with χ 2 value of 0.023. The tannin-based Rhizophora Spp. gave the nearest CT density profile to water substitute at all CT energies. This study indicated the suitability of Rhizophora Spp. particleboard as phantom material for the use in CT imaging studies

  9. Measurements of neutral density profiles using a deuterium Balmer-alpha diagnostic in the C-2 FRC plasma

    International Nuclear Information System (INIS)

    Gupta, Deepak K.; Deng, B. H.; Knapp, K.; Sun, X.; Thompson, M. C.

    2012-01-01

    In C-2 field-reversed configuration (FRC) device, low neutral density outside the FRC separatrix is required to minimize the charge exchange loss of fast particles. Titanium gettering is used in C-2 to reduce the wall recycling and keep the neutral density low in plasma edge. The measurements of neutral density radial profile are desirable to understand the plasma recycling and the effects of titanium gettering. These measurements are also needed to study the interaction of neutral beams with FRC plasma and confinement of fast ions. Diagnostic based on absolute deuterium Balmer-alpha (D-alpha) radiation measurements is developed and deployed on C-2 device to measure the radial profile of neutral density. Simultaneous measurements of electron density and temperature are done using CO 2 interferometer, Thomson scattering, and triple probes diagnostics along with absolute D-alpha radiation. Abel inversion was performed to get the time dependent radial profile of the local D-alpha emission density. Neutral density profiles are obtained under different machine conditions of titanium deposition.

  10. Global SAXS Data Analysis for Multilamellar Vesicles: Evolution of the Scattering Density Profile (SDP) Model

    Energy Technology Data Exchange (ETDEWEB)

    Heftberger, Peter [University of Graz, Institute of Molecular Biosciences, Austria; Kollmitzer, Benjamin [University of Graz, Institute of Molecular Biosciences, Austria; Heberle, Frederick A [ORNL; Pan, Jianjun [ORNL; Rappolt, Michael [University of Leeds, UK; Amenitsch, Heinz [Graz University of Technology; Kucerka, Norbert [Atomic Energy of Canada Limited (AECL), Canadian Neutron Beam Centre (CNBC) and Comenius University,; Katsaras, John [ORNL; Pabst, georg [University of Graz, Institute of Molecular Biosciences, Austria

    2014-01-01

    The highly successful scattering density profile (SDP) model, used to jointly analyze small-angle X-ray and neutron scattering data from unilamellar vesicles, has been adapted for use with data from fully hydrated, liquid crystalline multilamellar vesicles (MLVs). Using a genetic algorithm, this new method is capable of providing high-resolution structural information, as well as determining bilayer elastic bending fluctuations from standalone X-ray data. Structural parameters such as bilayer thickness and area per lipid were determined for a series of saturated and unsaturated lipids, as well as binary mixtures with cholesterol. The results are in good agreement with previously reported SDP data, which used both neutron and X-ray data. The inclusion of deuterated and non-deuterated MLV neutron data in the analysis improved the lipid backbone information but did not improve, within experimental error, the structural data regarding bilayer thickness and area per lipid.

  11. Current density profile control by programming of gas puffing and plasma current waveform in the JIPPT-II tokamak

    International Nuclear Information System (INIS)

    Toi, K.; Itoh, S.; Kadota, K.; Kawahata, K.; Noda, N.

    1979-03-01

    In the resistive shell tokamak, JIPP T-II, the current density profile control is carried out by pre-programming of both gas puffing and plasma current waveform. The major disruptions are completely suppressed by the method and a high density tokamak plasma with low q(a) is obtained with better MHD stability, where the line-average electron density n sub(e) 13 cm -3 and safety factor at plasma surface q(a) >= 2.2. The control criterion that the current density profile is successfully controlled is derived as a function of the ratio of plasma current to the electron density I sub(p)/n sub(e) in the current rising phase, i.e., 20 x 10 -13 -13 kA.cm 3 . (author)

  12. Tidal Disruption of Milky Way Satellites with Shallow Dark Matter Density Profiles

    Directory of Open Access Journals (Sweden)

    Ewa L. Łokas

    2016-11-01

    Full Text Available Dwarf galaxies of the Local Group provide unique possibilities to test current theories of structure formation. Their number and properties have put the broadly accepted cold dark matter model into question, posing a few problems. These problems now seem close to resolution due to the improved treatment of baryonic processes in dwarf galaxy simulations which now predict cored rather than cuspy dark matter profiles in isolated dwarfs with important consequences for their subsequent environmental evolution. Using N-body simulations, we study the evolution of a disky dwarf galaxy with such a shallow dark matter profile on a typical orbit around the Milky Way. The dwarf survives the first pericenter passage but is disrupted after the second due to tidal forces from the host. We discuss the evolution of the dwarf’s properties in time prior to and at the time of disruption. We demonstrate that the dissolution occurs on a rather short timescale as the dwarf expands from a spheroid into a stream with non-zero mean radial velocity. We point out that the properties of the dwarf at the time of disruption may be difficult to distinguish from bound configurations, such as tidally induced bars, both in terms of surface density and line-of-sight kinematics.

  13. Study of flow profile distortions and efficiency in counter pressure moderated partial filling micellar electrokinetic chromatography in relation to the relative buffer zone lengths.

    Science.gov (United States)

    Michalke, Daniela; Welsch, Thomas

    2002-06-25

    The influence of the relative buffer zone lengths on the efficiency was investigated in partial filling micellar electrokinetic chromatography using sodium dodecyl sulfate as separation additive. Varying relative zone lengths were obtained by applying identical initial separation zone lengths but different total lengths of the capillaries. Plate numbers of a homologous series of omega-phenylalcohols were measured to indicate the effect of both a changing relative zone length during the run and a counter pressure applied on the cathodic buffer reservoir. The magnitude and the course of these plate numbers are discussed on the basis of models for flow profile superposition and flow profile deformation which are caused by an intersegmental pressure arising at the boundary between the two buffer zones with different electroosmotic flow velocities. Calculation of the intersegmental pressure and of the resulting laminar flow components in the buffer zones on the basis of some equations for electroosmotic and hydrodynamic flow supported the interpretation that a long background buffer zone should be avoided

  14. Comparison of collisional radiative models for edge electron density reconstruction from Li I (2s-2p) emission profiles

    International Nuclear Information System (INIS)

    Stoschus, H.; Hudson, B.; Muñoz Burgos, J. M.; Thomas, D. M.; Schweinzer, J.

    2012-01-01

    Four collisional radiative models (CRMs) for reconstruction of the edge electron density profile from the measured Li I (2s-2p) emission profile of an accelerated lithium beam are compared using experimental data from DIII-D. It is shown for both L- and H-mode plasmas that edge density profiles reconstructed with the CRMs DDD2, ABSOLUT, [Sasaki et al. Rev. Sci. Instrum. 64, 1699 (1993)] and a new model developed at DIII-D agree in a density scan from n e ped = (2.0–6.5) × 10 19 m −3 within 20%, 20%, eff = 1–6 up to a factor of two but agree with Thomson data for Z eff = 1–2 within the error bars.

  15. Petrophysical Properties (Density and Magnetization of Rocks from the Suhbaatar-Ulaanbaatar-Dalandzadgad Geophysical Profile in Mongolia and Their Implications

    Directory of Open Access Journals (Sweden)

    Tao Yang

    2013-01-01

    Full Text Available Petrophysical properties of 585 rock samples from the Suhbaatar-Ulaanbaatar-Dalandzadgad geophysical profile in Mongolia are presented. Based on the rock classifications and tectonic units, petrophysical parameters (bulk density, magnetic susceptibility, intensity of natural remanent magnetization, and Köenigsberger ratio of these rocks are summarized. Results indicate that (1 significant density contrast of different rocks would result in variable gravity anomalies along the profile; (2 magnetic susceptibility and natural remanent magnetization of all rocks are variable, covering 5-6 orders of magnitude, which would make a variable induced magnetization and further links to complex magnetic anomalies in ground surface; (3 the distribution of rocks with different lithologies controls the pattern of lithospheric magnetic anomaly along the profile. The petrophysical database thus provides not only one of the keys to understand the geological history and structure of the profile, but also essential information for analysis and interpretation of the geophysical (e.g., magnetic and gravity survey data.

  16. Petrophysical properties (density and magnetization) of rocks from the Suhbaatar-Ulaanbaatar-Dalandzadgad geophysical profile in Mongolia and their implications.

    Science.gov (United States)

    Yang, Tao; Gao, Jintian; Gu, Zuowen; Dagva, Baatarkhuu; Tserenpil, Batsaikhan

    2013-01-01

    Petrophysical properties of 585 rock samples from the Suhbaatar-Ulaanbaatar-Dalandzadgad geophysical profile in Mongolia are presented. Based on the rock classifications and tectonic units, petrophysical parameters (bulk density, magnetic susceptibility, intensity of natural remanent magnetization, and Köenigsberger ratio) of these rocks are summarized. Results indicate that (1) significant density contrast of different rocks would result in variable gravity anomalies along the profile; (2) magnetic susceptibility and natural remanent magnetization of all rocks are variable, covering 5-6 orders of magnitude, which would make a variable induced magnetization and further links to complex magnetic anomalies in ground surface; (3) the distribution of rocks with different lithologies controls the pattern of lithospheric magnetic anomaly along the profile. The petrophysical database thus provides not only one of the keys to understand the geological history and structure of the profile, but also essential information for analysis and interpretation of the geophysical (e.g., magnetic and gravity) survey data.

  17. Note: Interpolation for evaluation of a two-dimensional spatial profile of plasma densities at low gas pressures

    International Nuclear Information System (INIS)

    Oh, Se-Jin; Kim, Young-Chul; Chung, Chin-Wook

    2011-01-01

    An interpolation algorithm for the evaluation of the spatial profile of plasma densities in a cylindrical reactor was developed for low gas pressures. The algorithm is based on a collisionless two-dimensional fluid model. Contrary to the collisional case, i.e., diffusion fluid model, the fitting algorithm depends on the aspect ratio of the cylindrical reactor. The spatial density profile of the collisionless fitting algorithm is presented in two-dimensional images and compared with the results of the diffusion fluid model.

  18. First observation of density profile in directly laser-driven polystyrene targets for ablative Rayleigh-Taylor instability research

    International Nuclear Information System (INIS)

    Fujioka, Shinsuke; Shiraga, Hiroyuki; Nishikino, Masaharu; Shigemori, Keisuke; Sunahara, Atsushi; Nakai, Mitsuo; Azechi, Hiroshi; Nishihara, Katsunobu; Yamanaka, Tatsuhiko

    2003-01-01

    The temporal evolution of the density profile of a directly laser-driven polystyrene target was observed for the first time using an x-ray penumbral imaging technique coupled with side-on x-ray backlighting at the GEKKO XII [C. Yamanaka et al., IEEE J. Quantum Electron. QE-17, 1639 (1981)]-High Intensity Plasma Experimental Research laser facility (I L =0.7x10 14 W/cm 2 , λ L =0.35 μm). This density measurement makes it possible to experimentally confirm all physical parameters [γ(k),k,g,m,ρ a ,L m ] appearing in the modified Takabe formula for the growth rate of the ablative Rayleigh-Taylor instability. The measured density profiles were well reproduced by a one-dimensional hydrodynamic simulation code. The density measurement contributes toward fully understanding the ablative Rayleigh-Taylor instability

  19. Uncovering genes and ploidy involved in the high diversity in root hair density, length and response to local scarce phosphate in Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Markus G Stetter

    Full Text Available Plant root hairs increase the root surface to enhance the uptake of sparingly soluble and immobile nutrients, such as the essential nutrient phosphorus, from the soil. Here, root hair traits and the response to scarce local phosphorus concentration were studied in 166 accessions of Arabidopsis thaliana using split plates. Root hair density and length were correlated, but highly variable among accessions. Surprisingly, the well-known increase in root hair density under low phosphorus was mostly restricted to genotypes that had less and shorter root hairs under P sufficient conditions. By contrast, several accessions with dense and long root hairs even had lower hair density or shorter hairs in local scarce phosphorus. Furthermore, accessions with whole-genome duplications developed more dense but phosphorus-insensitive root hairs. The impact of genome duplication on root hair density was confirmed by comparing tetraploid accessions with their diploid ancestors. Genome-wide association mapping identified candidate genes potentially involved in root hair responses tp scarce local phosphate. Knock-out mutants in identified candidate genes (CYR1, At1g32360 and RLP48 were isolated and differences in root hair traits in the mutants were confirmed. The large diversity in root hair traits among accessions and the diverse response when local phosphorus is scarce is a rich resource for further functional analyses.

  20. Analysis of plasma equilibrium based on orbit-driven current density profile in steady-state plasma on QUEST

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, K., E-mail: nakamura@triam.kyushu-u.ac.jp [RIAM, Kyushu University, Kasuga 816-8580 (Japan); Alam, M.M. [IGSES, Kyushu University, Kasuga 816-8580 (Japan); Jiang, Y.Z. [Tsinghua University, Beijing 100084 (China); Mitarai, O. [Tokai University, Kumamoto 862-8652 (Japan); Kurihara, K.; Kawamata, Y.; Sueoka, M.; Takechi, M. [Japan Atomic Energy Agency, Naka 311-0193 (Japan); Hasegawa, M.; Tokunaga, K.; Araki, K.; Zushi, H.; Hanada, K.; Fujisawa, A.; Idei, H.; Nagashima, Y.; Kawasaki, S.; Nakashima, H.; Higashijima, A.; Nagata, T. [RIAM, Kyushu University, Kasuga 816-8580 (Japan); and others

    2016-11-01

    Highlights: • High energy particle guiding center orbit is calculated as a contour plot of conserved variable. • Current density profile is analyzed based on the orbit-driven current. • Plasma equilibrium is reconstructed by considering the hollow current profile. - Abstract: In the present RF-driven (ECCD) steady-state plasma on QUEST (B{sub t} = 0.25 T, R = 0.68 m, a = 0.40 m), plasma current seems to flow in the open magnetic surface outside of the closed magnetic surface in the low-field region according to plasma current fitting (PCF) method. We consider that the current in the open magnetic surface is due to orbit-driven current by high-energy particles in RF-driven plasma. So based on the analysis of current density profile based on the orbit-driven current, plasma equilibrium is to be calculated. We calculated high energy particles guiding center orbits as a contour plot of conserved variable in Hamiltonian formulation and considered particles initial position with different levels of energy and pitch angles that satisfy resonance condition. Then the profile of orbit-driven current is estimated by multiplying the particle density on the resonance surface and the velocity on the orbits. This analysis shows negative current near the magnetic axis and hollow current profile is expected even if pressure driven current is considered. Considering the hollow current profile shifted toward the low-field region, the equilibrium is fitted by J-EFIT coded by MATLAB.

  1. Formulation of detector response function to calculate the power density profiles using in-core neutron detectors

    International Nuclear Information System (INIS)

    Ahmed, S. A.; Peter, J. K.; Semmler, W.; Shultis, J. K.

    2007-01-01

    By measuring neutron fluxes at different locations throughout a core, it's possible to derive the power-density profile P k (W cm - 3), at an axial depth z of fuel rod k. Micro-pocket fission detectors (MPFD) have been fabricated to perform such in-core neutron flux measurements. The purpose of this study is to develop a mathematical model to obtain axial power density distributions in the fuel rods from the in-core responses of the MPFDs

  2. Construction of an SNP-based high-density linkage map for flax (Linum usitatissimum L.) using specific length amplified fragment sequencing (SLAF-seq) technology.

    Science.gov (United States)

    Yi, Liuxi; Gao, Fengyun; Siqin, Bateer; Zhou, Yu; Li, Qiang; Zhao, Xiaoqing; Jia, Xiaoyun; Zhang, Hui

    2017-01-01

    Flax is an important crop for oil and fiber, however, no high-density genetic maps have been reported for this species. Specific length amplified fragment sequencing (SLAF-seq) is a high-resolution strategy for large scale de novo discovery and genotyping of single nucleotide polymorphisms. In this study, SLAF-seq was employed to develop SNP markers in an F2 population to construct a high-density genetic map for flax. In total, 196.29 million paired-end reads were obtained. The average sequencing depth was 25.08 in male parent, 32.17 in the female parent, and 9.64 in each F2 progeny. In total, 389,288 polymorphic SLAFs were detected, from which 260,380 polymorphic SNPs were developed. After filtering, 4,638 SNPs were found suitable for genetic map construction. The final genetic map included 4,145 SNP markers on 15 linkage groups and was 2,632.94 cM in length, with an average distance of 0.64 cM between adjacent markers. To our knowledge, this map is the densest SNP-based genetic map for flax. The SNP markers and genetic map reported in here will serve as a foundation for the fine mapping of quantitative trait loci (QTLs), map-based gene cloning and marker assisted selection (MAS) for flax.

  3. Confinement bifurcation by current density profile perturbation in TUMAN-3M tokamak

    International Nuclear Information System (INIS)

    Lebedev, S.V.; Andreiko, M.V.; Askinazi, L.G.

    2001-01-01

    In the recent experiments performed on TUMAN-3M the possibility to switch on/off the H-mode by current density profile perturbations has been shown. The j(r) perturbations were created by fast Current Ramp Up/Down or by Magnetic Compression produced by a fast increase of the toroidal magnetic field. It was found that the Current Ramp Up (CRU) and Magnetic Compression (MC) are useful means for H-mode triggering. The Current Ramp Down (CRD) triggers H-L transition. The difference in the j(r) behavior in these experiments suggests the peripheral current density may not be the critical parameter controlling L-H and H-L transitions. Confinement bifurcation in the above experiments could be explained by the unified mechanism: variation of a turbulent transport resulting from radial electric field emerging near the edge in the conditions of alternating toroidal electric field Ej and different electron and ion collisionalities. According to the suggested model the toroidal field E φ arising in the periphery during the CRU and MC processes amplifies Ware drift, which mainly influences electron component. As a result the favorable for the transition negative (inward directed) E r emerges. In the CRD scenario, when E φ is opposite to the total plasma current direction, the mechanism should generate positive E r , which is thought to be unfavorable for the H-mode. The experimental data on L-H and H-L transitions in various scenarios and the results of the modeling of E r emerging in the CRU experiment are presented in the paper. (author)

  4. Using specific length amplified fragment sequencing to construct the high-density genetic map for Vitis ( Vitis vinifera L. × Vitis amurensis Rupr.

    Directory of Open Access Journals (Sweden)

    yinshan eGuo

    2015-06-01

    Full Text Available In this study, 149 F1 plants from the interspecific cross between ‘Red Globe’ (Vitis vinifera L. and ‘Shuangyou’ (Vitis amurensis Rupr. and the parent were used to construct a molecular genetic linkage map by using the specific length amplified fragment sequencing technique. DNA sequencing generated 41.282 Gb data consisting of 206,411,693 paired-end reads. The average sequencing depths were 68.35 for ‘Red Globe,’ 63.65 for ‘Shuangyou,’ and 8.01 for each progeny. In all, 115,629 high-quality specific length amplified fragments were detected, of which 42,279 were polymorphic. The genetic map was constructed using 7,199 of these polymorphic markers. These polymorphic markers were assigned to 19 linkage groups; the total length of the map was 1929.13 cM, with an average distance of 0.28 cM between each maker. To our knowledge, the genetic maps constructed in this study contain the largest number of molecular markers. These high-density genetic maps might form the basis for the fine quantitative trait loci mapping and molecular-assisted breeding of grape.

  5. Comparison of apical transportation and change of working length in K3, NRT AND PROFILE rotary instruments using transparent resin block

    Directory of Open Access Journals (Sweden)

    Min-Jung Yoon

    2011-01-01

    Full Text Available Objectives The purpose of this study is to compare the apical transportation and working length change in curved root canals created in resin blocks, using 3 geometrically different types of Ni-Ti files, K3, NRT, and Profile. Materials and Methods The curvature of 30 resin blocks was measured by Schneider technique and each groups of Ni-Ti files were allocated with 10 resin blocks at random. The canals were shaped with Ni-Ti files by Crown-down technique. It was analyzed by Double radiograph superimposition method (Backman CA 1992, and for the accuracy and consistency, specially designed jig, digital X-ray, and CAD/CAM software for measurement of apical transportation were used. The amount of apical transportation was measured at 0, 1, 3, 5 mm from 'apical foramen - 0.5 mm' area, and the alteration of the working length before and after canal shaping was also measured. For statistics, Kruskal-Wallis One Way Analysis was used. Results There was no significant difference between the groups in the amount of working length change and apical transportation at 0, 1, and 3 mm area (p = 0.027, however, the amount of apical transportation at 5 mm area showed significant difference between K3 and Profile system (p = 0.924. Conclusions As a result of this study, the 3 geometrically different Ni-Ti files showed no significant difference in apical transportation and working length change and maintained the original root canal shape.

  6. Novel lipoprotein density profiling in healthy dogs of various breeds, healthy miniature schnauzers, and miniature schnauzers with hyperlipidemia

    Science.gov (United States)

    2013-01-01

    Background Despite the importance of abnormalities in lipoprotein metabolism in clinical canine medicine, the fact that most previously used methods for lipoprotein profiling are rather laborious and time-consuming has been a major obstacle to the wide clinical application and use of lipoprotein profiling in this species. The aim of the present study was to assess the feasibility of a continuous lipoprotein density profile (CLPDP) generated within a bismuth sodium ethylenediaminetetraacetic acid (NaBiEDTA) density gradient to characterize and compare the lipoprotein profiles of healthy dogs of various breeds, healthy Miniature Schnauzers, and Miniature Schnauzers with primary hypertriacylglycerolemia. A total of 35 healthy dogs of various breeds with serum triacylglycerol (TAG) and cholesterol concentrations within their respective reference intervals were selected for use as a reference population. Thirty-one Miniature Schnauzers with serum TAG and cholesterol concentrations within their respective reference intervals and 31 Miniature Schnauzers with hypertriacylglyceridemia were also included in the study. Results The results suggest that CLPDP using NaBiEDTA provides unique diagnostic information in addition to measurements of serum TAG and cholesterol concentrations and that it is a useful screening method for dogs with suspected lipoprotein metabolism disorders. Using the detailed and continuous density distribution information provided by the CLPDP, important differences in lipoprotein profiles can be detected even among dogs that have serum TAG and cholesterol concentrations within the reference interval. Miniature Schnauzers with serum TAG and cholesterol concentrations within the reference interval had significantly different lipoprotein profiles than dogs of various other breeds. In addition, it was further established that specific lipoprotein fractions are associated with hypertriacylglyceridemia in Miniature Schnauzers. Conclusions The results of the

  7. Gravimetric and density profiling using the combination of surface acoustic waves and neutron reflectivity.

    Science.gov (United States)

    Toolan, Daniel T W; Barker, Robert; Gough, Tim; Topham, Paul D; Howse, Jonathan R; Glidle, Andrew

    2017-02-01

    A new approach is described herein, where neutron reflectivity measurements that probe changes in the density profile of thin films as they absorb material from the gas phase have been combined with a Love wave based gravimetric assay that measures the mass of absorbed material. This combination of techniques not only determines the spatial distribution of absorbed molecules, but also reveals the amount of void space within the thin film (a quantity that can be difficult to assess using neutron reflectivity measurements alone). The uptake of organic solvent vapours into spun cast films of polystyrene has been used as a model system with a view to this method having the potential for extension to the study of other systems. These could include, for example, humidity sensors, hydrogel swelling, biomolecule adsorption or transformations of electroactive and chemically reactive thin films. This is the first ever demonstration of combined neutron reflectivity and Love wave-based gravimetry and the experimental caveats, limitations and scope of the method are explored and discussed in detail. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  8. Classification of X-ray solar flares regarding their effects on the lower ionosphere electron density profile

    Directory of Open Access Journals (Sweden)

    D. P. Grubor

    2008-06-01

    Full Text Available The classification of X-ray solar flares is performed regarding their effects on the Very Low Frequency (VLF wave propagation along the Earth-ionosphere waveguide. The changes in propagation are detected from an observed VLF signal phase and amplitude perturbations, taking place during X-ray solar flares. All flare effects chosen for the analysis are recorded by the Absolute Phase and Amplitude Logger (AbsPal, during the summer months of 2004–2007, on the single trace, Skelton (54.72 N, 2.88 W to Belgrade (44.85 N, 20.38 E with a distance along the Great Circle Path (GCP D≈2000 km in length.

    The observed VLF amplitude and phase perturbations are simulated by the computer program Long-Wavelength Propagation Capability (LWPC, using Wait's model of the lower ionosphere, as determined by two parameters: the sharpness (β in 1/km and reflection height (H' in km. By varying the values of β and H' so as to match the observed amplitude and phase perturbations, the variation of the D-region electron density height profile Ne(z was reconstructed, throughout flare duration. The procedure is illustrated as applied to a series of flares, from class C to M5 (5×10−5 W/m2 at 0.1–0.8 nm, each giving rise to a different time development of signal perturbation.

    The corresponding change in electron density from the unperturbed value at the unperturbed reflection height, i.e. Ne(74 km=2.16×108 m−3 to the value induced by an M5 class flare, up to Ne(74 km=4×1010 m−3 is obtained. The β parameter is found to range from 0.30–0.49 1/km and the reflection height H' to vary from 74–63 km. The changes in Ne(z during the flares, within height range z=60 to 90 km are determined, as well.

  9. Classification of X-ray solar flares regarding their effects on the lower ionosphere electron density profile

    Directory of Open Access Journals (Sweden)

    D. P. Grubor

    2008-06-01

    Full Text Available The classification of X-ray solar flares is performed regarding their effects on the Very Low Frequency (VLF wave propagation along the Earth-ionosphere waveguide. The changes in propagation are detected from an observed VLF signal phase and amplitude perturbations, taking place during X-ray solar flares. All flare effects chosen for the analysis are recorded by the Absolute Phase and Amplitude Logger (AbsPal, during the summer months of 2004–2007, on the single trace, Skelton (54.72 N, 2.88 W to Belgrade (44.85 N, 20.38 E with a distance along the Great Circle Path (GCP D≈2000 km in length. The observed VLF amplitude and phase perturbations are simulated by the computer program Long-Wavelength Propagation Capability (LWPC, using Wait's model of the lower ionosphere, as determined by two parameters: the sharpness (β in 1/km and reflection height (H' in km. By varying the values of β and H' so as to match the observed amplitude and phase perturbations, the variation of the D-region electron density height profile Ne(z was reconstructed, throughout flare duration. The procedure is illustrated as applied to a series of flares, from class C to M5 (5×10−5 W/m2 at 0.1–0.8 nm, each giving rise to a different time development of signal perturbation. The corresponding change in electron density from the unperturbed value at the unperturbed reflection height, i.e. Ne(74 km=2.16×108 m−3 to the value induced by an M5 class flare, up to Ne(74 km=4×1010 m−3 is obtained. The β parameter is found to range from 0.30–0.49 1/km and the reflection height H' to vary from 74–63 km. The changes in Ne(z during the flares, within height range z=60 to 90 km are determined, as well.

  10. Density profile and cholesterol concentration of serum lipoproteins in experimental animals and human subjects on hypercholesterolaemic diets

    NARCIS (Netherlands)

    Beynen, A.C.; Terpstra, A.H.M.

    1984-01-01

    1. 1. The density profile of Sudan black stained serum lipoproteins was studied in human subjects and various animal species on diets supplemented with cholesterol. 2. 2. In the animals studied (rabbits, calves, mice, chickens, rats and guinea-pigs), the feeding of cholesterol resulted in an

  11. Charge and current density profiles of a degenerate magnetized free-electron gas near a hard wall

    NARCIS (Netherlands)

    Kettenis, M.M.; Suttorp, L.G.

    1998-01-01

    The charge and current densities of a completely degenerate free-electron gas in a uniform magnetic field are found to have a damped oscillatory spatial dependence near a wall that is parallel to the magnetic field. For large distances from the wall the behaviour of the associated profile functions

  12. Evaluation of a Magnetically-Filtered Faraday Probe for Measuring the ion Current Density Profile of a Hall Thruster

    National Research Council Canada - National Science Library

    Rovey, Joshua L; Walker, Micthell L; Gallimore, Alec D; Peterson, Peter Y

    2004-01-01

    .... In this study, a MFFP, boxed Faraday probe (BFP), and nude Faraday probe are used to measure the ion current density profile of a 5 kW Hall thruster operated over the range of 300-500 V and 5-10 mg...

  13. Electron density profiles for middle latitudes. Theoretical model results and its comparisons with observations for the bottomside F region

    International Nuclear Information System (INIS)

    Zhang, S.R.; Radicella, S.M.; Zhang, M.L.; Huang, X.Y.

    1996-01-01

    Results of the theoretical models for electron density profile in the F region are used in IRI (International Reference Ionosphere) to provide complementary data to the experimental database, for a better understanding of physical processes and characteristics involved. 8 refs, 6 figs

  14. Simulations of current density profile control using lower hybrid current drive in the TdeV tokamak

    International Nuclear Information System (INIS)

    Fuchs, V.; Bonoli, P.T.; Shkarofsky, I.P.; Cote, A.; Demers, Y.; Janicki, C.

    1995-01-01

    The physics basis of a simulation model for lower hybrid current drive (LHCD) is discussed. Issues associated with LH power deposition - wave propagation, mode conversion and cut-offs in toroidal geometry, as well as linear and quasi-linear Landau damping - are analysed. A simulation model (ACCOME) is applied to the LHCD experiment now operating on the Tokamak de Varennes (TdeV). The profiles and values of density and temperature needed as inputs to ACCOME are taken from the experiment. The predictions of current density and loop voltage from ACCOME are then compared with experimental LHCD results. Possible LH current profile control experiments are also analysed for TdeV using composite LH spectra to control the location of RF power deposition. Finally, the relevance of these current profile control results to future devices is discussed and an example is shown for ITER-like parameters. (author). 44 refs, 15 figs, 4 tabs

  15. Expression profiling on high-density DNA grids to detect novel targets in dendritic cells

    International Nuclear Information System (INIS)

    Weissmann, M.

    2000-10-01

    Gene expression analyzes on a large scale using DNA microarrays is a novel approach to study transcription of thousands of genes in parallel. By comparing gene expression profiles of different cell-types and of cells in different activation, novel regulatory networks will be identified that are unique to a cell-type and hence, important in its biological function. Among the differentially expressed genes many novel drug targets will be found. The Genetic department of the Novartis Research Institute was following this approach to identify novel genes, which are critical in the antigen presenting function of DCs and could become promising drug targets. Drugs that modulate effector functions of DCs towards induction of energy or tolerance in T-cells could be useful in the treatment of chronic inflammatory or autoimmune diseases. By using specific robotics equipment high-density cDNA grids on nylon membranes have been produced for hybridizations with various radioactive labeled DNA probes. By our format, based on 384 well plates and limited by the resolution power of our current image analysis software, 27.648 cDNA clones, bacterial colonies or pure DNA, were spotted on one filter. For RNA profiling, we generated filters containing a collection of genes expressed in peripheral blood DCs or monocytes and characterized by oligonucleotide fingerprinting (ONF) as being differentially expressed. The gene collection contained many unknown genes. Sequence analysis of to date 18.000 cDNA clones led to an estimate of 5.000 non-redundant genes being represented in the collection. 10 % of them are either completely unknown or homologous to rare ESTs (expressed sequence tags) in the public EST database. These clones occurred predominantly in small fingerprint clusters and were therefore assumed to be rarely expressed in DCs or monocytes. Some of those genes may become novel drug targets if their expression is DC specific or induced by external stimuli driving DCs into

  16. Improved density profile measurements in the C-2U advanced beam-driven Field-Reversed Configuration (FRC) plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Beall, M., E-mail: mbeall@trialphaenergy.com; Deng, B. H.; Gota, H. [Tri Alpha Energy, Inc., P.O. Box 7010, Rancho Santa Margarita, California 92688 (United States)

    2016-11-15

    In the prior C-2 experiment, electron density was measured using a two-color 6-chord CO{sub 2}/HeNe interferometer. Analysis shows that high-frequency common mode phase noise can be reduced by a factor of 3 by constructing a reference chord. In the system upgrade from C-2 to C-2U a 4-chord far-infrared laser interferometer was developed, which demonstrated superior sensitivity (1 × 10{sup 16} m{sup −2} at >1 MHz bandwidth) and solved the under spatial sampling issue of the C-2 interferometer system. Improved density-profile measurement results are presented in this paper, including evidence of fast-ion modified density profile and stabilization of the n = 1 plasma wobble mode.

  17. Measurement of radiation profile at density ramp-up phase by using AXUV photodiode arrays in Heliotron J

    International Nuclear Information System (INIS)

    Watanabe, S.; Matsuoka, H.; Nagasaki, K.

    2008-01-01

    Measurement of radiation profiles has been made in electron cyclotron resonance heated (ECRH) plasmas on Heliotron J by using AXUV photodiode arrays. The measured radiation in low density is attributed to the effect of low energy photon below about 10 eV at edge region, and the profile in the chord-integrated signal is found to be broad. The radiation collapse at density ramp-up is also investigated. The radiation starts to decrease from the edge side at the collapse, and then the reduction in the radiation gradually shifts to the core plasma during the collapse event. The plasma starts to collapse when the edge radiation intensity reaches a certain value, independent of the density. (author)

  18. Restricted primitive model for electrical double layers: modified HNC theory of density profiles and Monte Carlo study of differential capacitance

    International Nuclear Information System (INIS)

    Ballone, P.; Pastore, G.; Tosi, M.P.

    1986-02-01

    Interfacial properties of an ionic fluid next to a uniformly charged planar wall are studied in the restricted primitive model by both theoretical and Monte Carlo methods. The system is a 1:1 fluid of equisized charged hard spheres in a state appropriate to 1M aqueous electrolyte solutions. The interfacial density profiles of counterions and coions are evaluated by extending the hypernetted chain approximation (HNC) to include the leading bridge diagrams for the wall-ion correlations. The theoretical results compare well with those of grand canonical Monte Carlo computations of Torrie and Valleau over the whole range of surface charge density considered by these authors, thus resolving the earlier disagreement between statistical mechanical theories and simulation data at large charge densities. In view of the importance of the model as a testing ground for theories of the diffuse layer, the Monte Carlo calculations are tested by considering alternative choices for the basic simulation cell and are extended so as to allow an evaluation of the differential capacitance of the model interface by two independent methods. These involve numerical differentiation of the mean potential drop as a function of the surface charge density or alternatively an appropriate use of a fluctuation theory formula for the capacitance. The results of these two Monte Carlo approaches consistently indicate an initially smooth increase of the diffuse layer capacitance followed by structure at large charge densities, this behaviour being connected with layering of counterions as already revealed in the density profiles reported by Torrie and Valleau. (author)

  19. The predominant effect of stroke length on velocity profiles at the exit of axisymmetric synthetic jet actuators

    Czech Academy of Sciences Publication Activity Database

    Kordík, Jozef; Trávníček, Zdeněk; Timchenko, V.; Ismail, N.A.

    2017-01-01

    Roč. 66, August (2017), s. 197-208 ISSN 0142-727X R&D Projects: GA ČR(CZ) GA16-16596S Institutional support: RVO:61388998 Keywords : synthetic jet * stroke length * reynolds number Subject RIV: BK - Fluid Dynamics OBOR OECD: Fluids and plasma physics (including surface physics) Impact factor: 1.873, year: 2016 http://www.sciencedirect.com/science/article/pii/S0142727X17300073

  20. Implementation of reflectometry as a standard density profile diagnostic on DIII-D

    International Nuclear Information System (INIS)

    Zeng, L.; Doyle, E. J.; Luce, T. C.; Peebles, W. A.

    2001-01-01

    The profile reflectometer system on the DIII-D tokamak has been significantly upgraded in order to improve time coverage, data quality, and profile availability. The performance of the reflectometer system, which utilizes continuous frequency modulated (FMCW) radar techniques, has been improved as follows: First, a new PC-based data acquisition system has been installed, providing higher data sampling rates and larger memory depth. The higher sampling rate enables use of faster frequency sweeps of the FMCW microwave source, improving time resolution, and increasing profile accuracy. The larger memory depth enables longer data records, so that profiles can now be obtained throughout 5 s discharges at 100 Hz profile measurement rates, while continuous sampling at 10 MHz is available for 1 s for high time resolution physics studies. Second, an initial automated between-shots profile analysis capability is now available. Third, availability of the profiles to end users has been significantly improved

  1. Transport studies in FTU with decoupled temperature and current density profiles

    International Nuclear Information System (INIS)

    Bracco, G.; Buratti, P.; Micozzi, P.; Tudisco, O.

    1994-01-01

    Electron temperature profiles in tokamaks are subject to global constraints that can be attributed either to their link with current profiles, i.e. to MHD stability conditions, a clear example being sawtooth activity, or to other mechanisms like marginal stability. Also a direct effect on transport coefficients was attributed to the current profile. Fast current ramps in FTU ohmic pulses have been used to study the effect of current profile variations on the energy confinement time. The global profile constraint was transiently removed in these pulses, and variations in the shape of temperature profiles could be observed. Modified profiles were also observed in pulses with a strong central radiative sink; in this case the modification was not transient. Finally, the transport properties in the central region have been studied by the analysis of temperature evolution between crashes of very long period sawteeth; very small electron heat transport was found. (author) 6 refs., 5 figs

  2. A decentralised model of psychiatric care: Profile, length of stay and outcome of mental healthcare users admitted to a district-level public hospital in the Western Cape

    Directory of Open Access Journals (Sweden)

    Eileen Thomas

    2015-02-01

    Full Text Available Background. There is a lack of studies assessing the profile and outcome of psychiatric patients at entry-level public hospitals that are prescribed by the Mental Health Care Act to provide a decentralised model of psychiatric care. Objective. To assess the demographic and clinical profile as well as length of stay and outcomes of mental healthcare users admitted to a district-level public hospital in the Western Cape.  Method. Demographic data, clinical diagnosis, length of stay, referral profile and outcomes of patients (N=487 admitted to Helderberg Hospital during the period 1 January 2011 - 31 December 2011 were collected.  Results. Psychotic disorders were the most prevalent (n=287, 59% diagnoses, while 228 (47% of admission episodes had comorbid/secondary diagnoses. Substance use disorders were present in 184 (38% of admission episodes, 37 (57% of readmissions and 19 (61% of abscondments. Most admission episodes (n=372, 76% were discharged without referral to specialist/tertiary care.  Conclusion. Methamphetamine use places a significant burden on the provision of mental healthcare services at entry-level care. Recommendations for improving service delivery at this district-level public hospital are provided.

  3. Design of an O-mode frequency modulated reflectometry system for the measurement of Alborz Tokamak plasma density profile

    Energy Technology Data Exchange (ETDEWEB)

    Koohestani, Saeideh [Department of Energy Engineering and physics, Amirkabir University of Technology, Tehran, 15875-4413, Islamic Republic of Iran (Iran, Islamic Republic of); Amrollahi, Reza, E-mail: amrollahi@aut.ac.ir [Department of Energy Engineering and physics, Amirkabir University of Technology, Tehran, 15875-4413, Islamic Republic of Iran (Iran, Islamic Republic of); Moradi, Gholamreza [Department of Electrical Engineering, Amirkabir University of Technology, Tehran, 15875-4413, Islamic Republic of Iran (Iran, Islamic Republic of)

    2016-12-15

    Reflectometry is a common method for plasma diagnostic, in which microwaves are launched into the plasma and reflected at the critical surfaces. Comparing the reflected microwave signals with the launched waves would give rise to the plasma density profiles. In the present study, an ordinary mode (O-mode) frequency modulation (FM) reflectometry system has been designed for the electron density profile measurement of the Alborz Tokamak plasma. This system has been considered to operate at K-band (18–26.5 GHz) frequency range and scan the frequency band between 18 to 26 GHz in 40 μS. The density profile from major radius r = 47.9–51.55 cm can be measured in Alborz Tokamak plasma. Based on the Alborz Tokamak operational conditions, the characteristic frequencies, and some dimensional limitations, all parts of reflectometer have been designed so that an appropriate efficiency with minimum attenuation, especially in transmitting/receiving system would be achieved. A dual antenna and an oversized waveguide of X-band (8–12 GHz) for transmitting and receiving purposes and a balanced detector for absolute phase determination have been utilized. The details of the Alborz Tokamak FM reflectometry components focusing on the antenna and waveguide design and mounting are described in this paper. Additionally, the procedure of plasma profile reconstruction using the system output signal is discussed. This system uses signal phase shift to determine the position of the cutoff layer.

  4. Short-length and high-density TiO2 nanorod arrays for the efficient charge separation interface in perovskite solar cells

    International Nuclear Information System (INIS)

    Xiao, Guannan; Shi, Chengwu; Zhang, Zhengguo; Li, Nannan; Li, Long

    2017-01-01

    The TiO 2 nanorod arrays with the length of 70 nm, the diameter of 20 nm, and the areal density of 1000 µm −2 were firstly prepared by the hydrothermal method using the aqueous grown solution of 38 mM titanium isopropoxide and 6 M hydrochloric acid at 170 °C for 60 min. Over-500 nm-thickness CH 3 NH 3 PbI 3−x Br x absorber layers were successfully obtained by sequential deposition routes using 1.7 M PbI 2 ·DMSO complex precursor solution and 0.465 M isopropanol solution of the methylammonium halide mixture with the molar ratio of CH 3 NH 3 I/CH 3 NH 3 Br=85/15. The perovskite solar cells based on the TiO 2 nanorod array and 560 nm-thickness CH 3 NH 3 PbI 3−x Br x absorber layer exhibited the best photoelectric conversion efficiency (PCE) of 15.93%, while the corresponding planar perovskite solar cells without the TiO 2 nanorod array and with 530 nm-thickness CH 3 NH 3 PbI 3−x Br x absorber layer gave the best PCE of 12.82% at the relative humidity of 50–54%. - Graphical abstract: The TiO 2 nanorod arrays with the length of 70 nm, the diameter of 20 nm, and the areal density of 1000 µm −2 were prepared by the hydrothermal method using the aqueous grown solution of 38 mM titanium isopropoxide and 6 M hydrochloric acid at 170 °C for 60 min. The optimal annealing temperature of TiO 2 nanorod arrays was 450 °C. The perovskite solar cells based on the TiO 2 nanorod array and 560 nm-thickness CH 3 NH 3 PbI 3−x Br x absorber layer exhibited the best photoelectric conversion efficiency (PCE) of 15.93% and the average PCE of 13.41±2.52%, while the corresponding planar perovskite solar cells without the TiO 2 nanorod array and with 530 nm-thickness CH 3 NH 3 PbI 3−x Br x absorber layer gave the best PCE of 12.82% and the average PCE of 10.54±2.28% at the relative humidity of 50–54%. - Highlights: • Preparation of TiO 2 nanorod array with length of 70 nm and density of 1000 µm −2 . • Influence of annealing temperatures on the -OH content of Ti

  5. Short-length and high-density TiO{sub 2} nanorod arrays for the efficient charge separation interface in perovskite solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Guannan; Shi, Chengwu, E-mail: shicw506@foxmail.com; Zhang, Zhengguo; Li, Nannan; Li, Long

    2017-05-15

    The TiO{sub 2} nanorod arrays with the length of 70 nm, the diameter of 20 nm, and the areal density of 1000 µm{sup −2} were firstly prepared by the hydrothermal method using the aqueous grown solution of 38 mM titanium isopropoxide and 6 M hydrochloric acid at 170 °C for 60 min. Over-500 nm-thickness CH{sub 3}NH{sub 3}PbI{sub 3−x}Br{sub x} absorber layers were successfully obtained by sequential deposition routes using 1.7 M PbI{sub 2}·DMSO complex precursor solution and 0.465 M isopropanol solution of the methylammonium halide mixture with the molar ratio of CH{sub 3}NH{sub 3}I/CH{sub 3}NH{sub 3}Br=85/15. The perovskite solar cells based on the TiO{sub 2} nanorod array and 560 nm-thickness CH{sub 3}NH{sub 3}PbI{sub 3−x}Br{sub x} absorber layer exhibited the best photoelectric conversion efficiency (PCE) of 15.93%, while the corresponding planar perovskite solar cells without the TiO{sub 2} nanorod array and with 530 nm-thickness CH{sub 3}NH{sub 3}PbI{sub 3−x}Br{sub x} absorber layer gave the best PCE of 12.82% at the relative humidity of 50–54%. - Graphical abstract: The TiO{sub 2} nanorod arrays with the length of 70 nm, the diameter of 20 nm, and the areal density of 1000 µm{sup −2} were prepared by the hydrothermal method using the aqueous grown solution of 38 mM titanium isopropoxide and 6 M hydrochloric acid at 170 °C for 60 min. The optimal annealing temperature of TiO{sub 2} nanorod arrays was 450 °C. The perovskite solar cells based on the TiO{sub 2} nanorod array and 560 nm-thickness CH{sub 3}NH{sub 3}PbI{sub 3−x}Br{sub x} absorber layer exhibited the best photoelectric conversion efficiency (PCE) of 15.93% and the average PCE of 13.41±2.52%, while the corresponding planar perovskite solar cells without the TiO{sub 2} nanorod array and with 530 nm-thickness CH{sub 3}NH{sub 3}PbI{sub 3−x}Br{sub x} absorber layer gave the best PCE of 12.82% and the average PCE of 10.54±2.28% at the relative humidity of 50–54%. - Highlights:

  6. Measurements of Pfirsch-Schlueter current and pressure profile for the high density ECH plasmas in Heliotron DR

    International Nuclear Information System (INIS)

    Morimoto, S.; Yanagi, N.; Nakasuga, M.; Obiki, T.; Iiyoshi, A.; Uo, K.

    1988-01-01

    The Pfirsch-Schlueter current and pressure profiles are estimated from magnetic measurements for high density electron cyclotron heating (ECH) plasmas (n-bar e =(2-3)x10 13 cm -3 , T e0 =200-400 eV, (β) 0 (1-(r/a) 2 ) s , is about two in macroscopically stable plasmas. A fast loss of plasma energy from the centre to the periphery is observed during the onset of the MHD instability. This method of measuring the pressure profile shape is simple and useful for heliotron type devices. (author). 20 refs, 8 figs, 1 tab

  7. Aphid aerial density profiles are consistent with turbulent advection amplifying flight behaviours: abandoning the epithet ‘passive’

    Science.gov (United States)

    Reynolds, Andy M; Reynolds, Don R

    2008-01-01

    Seminal field studies led by C. G. Johnson in the 1940s and 1950s showed that aphid aerial density diminishes with height above the ground such that the linear regression coefficient, b, of log density on log height provides a single-parameter characterization of the vertical density profile. This coefficient decreases with increasing atmospheric stability, ranging from −0.27 for a fully convective boundary layer to −2.01 for a stable boundary layer. We combined a well-established Lagrangian stochastic model of atmospheric dispersal with simple models of aphid behaviour in order to account for the range of aerial density profiles. We show that these density distributions are consistent with the aphids producing just enough lift to become neutrally buoyant when they are in updraughts and ceasing to produce lift when they are in downdraughts. This active flight behaviour in a weak flier is thus distinctly different from the aerial dispersal of seeds and wingless arthropods, which is passive once these organisms have launched into the air. The novel findings from the model indicate that the epithet ‘passive’ often applied to the windborne migration of small winged insects is misleading and should be abandoned. The implications for the distances traversed by migrating aphids under various boundary-layer conditions are outlined. PMID:18782743

  8. Tokamak plasma self-organization and the possibility to have the peaked density profile in ITER

    NARCIS (Netherlands)

    Razumova, K. A.; Andreev, V. F.; Kislov, A. Y.; Kirneva, N. A.; Lysenko, S. E.; Pavlov, Y. D.; Shafranov, T. V.; Donne, A. J. H.; Hogeweij, G. M. D.; Spakman, G. W.; R. Jaspers,; Kantor, M.; Walsh, M.

    2009-01-01

    The self-organization of a tokamak plasma is a fundamental turbulent plasma phenomenon, which leads to the formation of a self-consistent pressure profile. This phenomenon has been investigated in several tokamaks with different methods of heating. It is shown that the normalized pressure profile

  9. 'Length'at Length

    Indian Academy of Sciences (India)

    Admin

    He was interested to know how `large' is the set of numbers x for which the series is convergent. Here large refers to its length. But his set is not in the class ♢. Here is another problem discussed by Borel. Consider .... have an infinite collection of pairs of new shoes and want to choose one shoe from each pair. We have an ...

  10. Ultrafast broadband frequency modulation of a continuous wave reflectometry system to measure density profiles on ASDEX Upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Silva, A.; Manso, M.E.; Cupido, L.; Albrecht, M.; Serra, F.; Varela, P.; Santos, J.; Vergamota, S.; Eusebio, F.; Fernandes, J.; Grossmann, T.; Kallenbach, A.; Kurzan, B.; Loureiro, C.; Meneses, L.; Nunes, I.; Silva, F.; Suttrop, W. [Associacao EURATOM/IST-Centro de Fusao Nuclear/Instituto Superior Tecnico, 1096 Lisboa Codex (Portugal); the ASDEX Upgrade Team

    1996-12-01

    A reflectometry system has been developed for ASDEX Upgrade to measure the plasma profile from the scrape-off layer until the bulk plasma, simultaneously at the high and low field sides. Unique features of the system are the ultrafast broadband frequency modulation of a continuous wave using solid state stable hyper abrupt tuned oscillators (down to 10 {mu}s), high and low field side channels and fully remote control operation, via optical fiber links. Due to the special design of the transmission line, with decoupled in going and out going lines and one-antenna configuration, the system is optimized for reception and spurious reflections are eliminated. The ultrafast operation guarantees that the effect of plasma turbulence is greatly reduced. Both features determine the high performance of the diagnostic. A dedicated data acquisition system handles the large amounts of data generated by the broadband operation. Recent developments include the operation of new channels and an automatic and accurate frequency calibration circuit. Also, advanced digital signal processing techniques were applied to obtain density profiles with high spatial and temporal (20 {mu}s) resolutions under turbulent plasma regions, e.g., the scrape-off layer. Experimental results are presented showing the great sensitivity of the diagnostic to plasma radial movements and its tolerance to vertical movements of the plasma. Density profiles measured in ELMy regimes illustrate the capabilities of the diagnostic to detect fast profile changes. {copyright} {ital 1996 American Institute of Physics.}

  11. Cross-correlation Weak Lensing of SDSS galaxy Clusters II: Cluster Density Profiles and the Mass--Richness Relation

    Energy Technology Data Exchange (ETDEWEB)

    Johnston, David E.; Sheldon, Erin S.; Wechsler, Risa H.; Rozo, Eduardo; Koester, Benjamin P.; Frieman, Joshua A.; McKay, Timothy A.; Evrard, August E.; Becker, Matthew; Annis, James

    2007-09-28

    We interpret and model the statistical weak lensing measurements around 130,000 groups and clusters of galaxies in the Sloan Digital Sky Survey presented by Sheldon et al. (2007). We present non-parametric inversions of the 2D shear profiles to the mean 3D cluster density and mass profiles in bins of both optical richness and cluster i-band luminosity. Since the mean cluster density profile is proportional to the cluster-mass correlation function, the mean profile is spherically symmetric by the assumptions of large-scale homogeneity and isotropy. We correct the inferred 3D profiles for systematic effects, including non-linear shear and the fact that cluster halos are not all precisely centered on their brightest galaxies. We also model the measured cluster shear profile as a sum of contributions from the brightest central galaxy, the cluster dark matter halo, and neighboring halos. We infer the relations between mean cluster virial mass and optical richness and luminosity over two orders of magnitude in cluster mass; the virial mass at fixed richness or luminosity is determined with a precision of {approx} 13% including both statistical and systematic errors. We also constrain the halo concentration parameter and halo bias as a function of cluster mass; both are in good agreement with predictions from N-body simulations of LCDM models. The methods employed here will be applicable to deeper, wide-area optical surveys that aim to constrain the nature of the dark energy, such as the Dark Energy Survey, the Large Synoptic Survey Telescope and space-based surveys.

  12. The large-scale correlations of multicell densities and profiles: implications for cosmic variance estimates

    Science.gov (United States)

    Codis, Sandrine; Bernardeau, Francis; Pichon, Christophe

    2016-08-01

    In order to quantify the error budget in the measured probability distribution functions of cell densities, the two-point statistics of cosmic densities in concentric spheres is investigated. Bias functions are introduced as the ratio of their two-point correlation function to the two-point correlation of the underlying dark matter distribution. They describe how cell densities are spatially correlated. They are computed here via the so-called large deviation principle in the quasi-linear regime. Their large-separation limit is presented and successfully compared to simulations for density and density slopes: this regime is shown to be rapidly reached allowing to get sub-percent precision for a wide range of densities and variances. The corresponding asymptotic limit provides an estimate of the cosmic variance of standard concentric cell statistics applied to finite surveys. More generally, no assumption on the separation is required for some specific moments of the two-point statistics, for instance when predicting the generating function of cumulants containing any powers of concentric densities in one location and one power of density at some arbitrary distance from the rest. This exact `one external leg' cumulant generating function is used in particular to probe the rate of convergence of the large-separation approximation.

  13. Wood density-moisture profiles in old-growth Douglas-fir and western hemlock.

    Science.gov (United States)

    W.Y. Pong; Dale R. Waddell; Lambert Michael B.

    1986-01-01

    Accurate estimation of the weight of each load of logs is necessary for safe and efficient aerial logging operations. The prediction of green density (lb/ft3) as a function of height is a critical element in the accurate estimation of tree bole and log weights. Two sampling methods, disk and increment core (Bergstrom xylodensimeter), were used to measure the density-...

  14. A full vectorial contrast source inversion scheme for three-dimensional acoustic imaging of both compressibility and density profiles.

    Science.gov (United States)

    van Dongen, Koen W A; Wright, William M D

    2007-03-01

    Imaging the two acoustic medium parameters density and compressibility requires the use of both the acoustic pressure and velocity wave fields, described via integral equations. Imaging is based on solving for the unknown medium parameters using known measured scattered wave fields, and it is difficult to solve this ill-posed inverse problem directly using a conjugate gradient inversion scheme. Here, a contrast source inversion method is used in which the contrast sources, defined via the product of changes in compressibility and density with the pressure and velocity wave fields, respectively, are computed iteratively. After each update of the contrast sources, an update of the medium parameters is obtained. Total variation as multiplicative regularization is used to minimize blurring in the reconstructed contrasts. The method successfully reconstructed three-dimensional contrast profiles based on changes in both density and compressibility, using synthetic data both with and without 50% white noise. The results were compared with imaging based only on the pressure wave field, where speed of sound profiles were solely based on changes in compressibility. It was found that the results improved significantly by using the full vectorial method when changes in speed of sound depended on changes in both compressibility and density.

  15. Determination of dislocation density by electron backscatter diffraction and X-ray line profile analysis in ferrous lath martensite

    International Nuclear Information System (INIS)

    Berecz, Tibor; Jenei, Péter; Csóré, András; Lábár, János; Gubicza, Jenő

    2016-01-01

    The microstructure and the dislocation density in as-quenched ferrous lath martensite were studied by different methods. The blocks, packets and variants formed due to martensitic transformation were identified and their sizes were determined by electron backscatter diffraction (EBSD). Concomitant transmission electron microscopy (TEM) investigation revealed that the laths contain subgrains with the size between 50 and 100 nm. A novel evaluation procedure of EBSD images was elaborated for the determination of the density and the space distribution of geometrically necessary dislocations from the misorientation distribution. The total dislocation density obtained by X-ray diffraction line profile analysis was in good agreement with the value determined by EBSD, indicating that the majority of dislocations formed due to martensitic transformation during quenching are geometrically necessary dislocations.

  16. Experimental and numerical investigations on the density profile of CO2 laser-produced Sn plasma for an EUVL source

    Science.gov (United States)

    Tao, Y.; Ueno, Y.; Yuspeh, S.; Burdt, R. A.; Amin, N.; Shaikh, N. M.; Tillack, M. S.; Najmabadi, F.

    2010-04-01

    Experimentally observed density profile of CO2 laser-produced Sn plasma was compared with that predicted by one dimensional hydrodynamic radiation numerical code. Experimental data showed a much smaller corona and a much shorter shift distance of the critical density from the initial target surface as compared with those predicted by an isothermal model and the numerical simulation. The possible reason may come from thin localized laser deposition region, less energy transport into the corona and into the dense region beyond the critical density. This research suggests that more efforts to understand the fundamental dominating the interaction of CO2 laser with high Z plasma are necessary to form a more solid foundation for the application of numerical method to the development of the EUVL source.

  17. Effect of L-arginine methyl ester (L-NAME) on hormonal profile and estrous cycle length in buffaloes (Bubalus bubalis).

    Science.gov (United States)

    Sagar, Pushp; Prasad, Jai Kishan; Prasad, Shiv; Gupta, Harihar Prasad; Das, Arup

    2012-10-01

    The present study was undertaken to evaluate the effect of L-arginine methyl ester (L-NAME), a nitric oxide synthase inhibitor on serum nitric oxide, progesterone, estradiol profiles and estrous cycle length in buffaloes. Murrah buffaloes (n = 16) exhibiting regular estrous cycles were randomly allocated to two groups of eight animals. In the treatment group, buffaloes were administered 400 mg/h L-NAME over 2 h (total dose = 800 mg) via the coccygeal artery and the aorta abdominalis on day 15 of the estrous cycle. In the control group, normal saline was infused on the same day of the cycle by the same route. Blood samples were collected every 4 h on days 15 and 16, and once daily from days 17 to 21 of the estrous cycle for the assay of progesterone, estradiol and nitric oxide. L-NAME treatment significantly (p cycle. Serum progesterone concentration increased significantly (p cycle length was 19.8 ± 0.36 and 23.6 ± 0.17 days for control and treated group buffalo (p cycle inhibited serum nitric oxide concentration resulting in increased progesterone production and extension of the effective life of the corpus luteum, thus prolonging the estrous cycle length.

  18. ROSCOE Manual, Volume 14C - Further Density Profiles of Selected Atmospheric Species.

    Science.gov (United States)

    1979-06-30

    Atmospheric Models and Profiles 20 ABSTRACT (Continue on reverse side If necessary and identify by block number) Profiles and models of ambient...World-Wide Atmospheric Models (Surface to 25-km Altitude)," NASA CR-2082 (Allied Research Associates, Inc. 9G-88F), July 1972. SG-71 D.B. Spiegler...and J.R. Greaves, "Development of Four-Dimensional Atmospheric Models (World-Wide)," NASA CR61362 (Allied Research Associates, Inc.), August 1971. Si-77

  19. Modelling of the energy density deposition profiles of ultrashort laser pulses focused in optical media

    International Nuclear Information System (INIS)

    Vidal, F; Lavertu, P-L; Bigaouette, N; Moore, F; Brunette, I; Giguere, D; Kieffer, J-C; Olivie, G; Ozaki, T

    2007-01-01

    The propagation of ultrashort laser pulses in dense optical media is investigated theoretically by solving numerically the nonlinear Schroedinger equation. It is shown that the maximum energy density deposition as a function of the pulse energy presents a well-defined threshold that increases with the pulse duration. As a consequence of plasma defocusing, the maximum energy density deposition is generally smaller and the size of the energy deposition zone is generally larger for shorter pulses. Nevertheless, significant values of the energy density deposition can be obtained near threshold, i.e., at lower energy than for longer pulses

  20. Development of high-polarization Fe/Ge neutron polarizing supermirror: Possibility of fine-tuning of scattering length density in ion beam sputtering

    Science.gov (United States)

    Maruyama, R.; Yamazaki, D.; Akutsu, K.; Hanashima, T.; Miyata, N.; Aoki, H.; Takeda, M.; Soyama, K.

    2018-04-01

    The multilayer structure of Fe/Si and Fe/Ge systems fabricated by ion beam sputtering (IBS) was investigated using X-ray and polarized neutron reflectivity measurements and scanning transmission electron microscopy with energy-dispersive X-ray analysis. The obtained result revealed that the incorporation of sputtering gas particles (Ar) in the Ge layer gives rise to a marked reduction in the neutron scattering length density (SLD) and contributes to the SLD contrast between the Fe and Ge layers almost vanishing for spin-down neutrons. Bundesmann et al. (2015) have shown that the implantation of primary Ar ions backscattered at the target is responsible for the incorporation of Ar particles and that the fraction increases with increasing ion incidence angle and increasing polar emission angle. This leads to a possibility of fine-tuning of the SLD for the IBS, which is required to realize a high polarization efficiency of a neutron polarizing supermirror. Fe/Ge polarizing supermirror with m = 5 fabricated under the same condition showed a spin-up reflectivity of 0.70 at the critical momentum transfer. The polarization was higher than 0.985 for the qz range where the correction for the polarization inefficiencies of the beamline works properly. The result of the polarized neutron reflectivity measurement suggests that the "magnetically-dead" layers formed at both sides of the Fe layer, together with the SLD contrast, play a critical role in determining the polarization performance of a polarizing supermirror.

  1. Density functional theory study of silodithiophene thiophenepyrrolopyrroledion-based small molecules: The effect of alkyl side chain length in electron donor materials

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Dong Kyun; Yeo, Hak; Kwak, Kyung Won [Dept. of Chemistry, Chung-Ang University, Seoul (Korea, Republic of); Yoon, Young Woon; Kim, Bong Soo [Photo-electronic Hybrids Research Center, Korea Institute of Science and Technology, Seoul (Korea, Republic of); Lee, Kyung Koo [Dept. of Chemistry, Kunsan National University, Gunsan (Korea, Republic of)

    2015-02-15

    Push–pull small molecules are promising electron-donor materials for organic solar cells. Thus, precise prediction of their electronic structures is of paramount importance to control the optical and electrical properties of the solar cells. Various types of alkyl chains are usually introduced to increase solubility and modify the morphology of the resulting molecular films. Here, using density functional theory (DFT) and time-dependent DFT (TD-DFT), we report the precise effect of increasing the length of the alkyl chain on the electronic structure of an electron donor molecule 6,60-((4,4-dialkyl-4H-silolo[3,2-b:4,5-b′]-dithiophene-2,6-diyl) bis(thiophene-5,2-diyl))bis(2,5-alkyl-3-(thiophen-2-yl) -2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dione) (DTS1TDPP). Alkyl groups were attached to the bridging position (silicon atom) of the fused rings and nitrogen atom of the pyrrolopyrroledione groups. We demonstrate that the alkyl groups do not perturb the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels, π-delocalized backbone structure, and UV–Vis absorption spectrum when they are placed at the least steric effect positions.

  2. Short-length and high-density TiO2 nanorod arrays for the efficient charge separation interface in perovskite solar cells

    Science.gov (United States)

    Xiao, Guannan; Shi, Chengwu; Zhang, Zhengguo; Li, Nannan; Li, Long

    2017-05-01

    The TiO2 nanorod arrays with the length of 70 nm, the diameter of 20 nm, and the areal density of 1000 μm-2 were firstly prepared by the hydrothermal method using the aqueous grown solution of 38 mM titanium isopropoxide and 6 M hydrochloric acid at 170 °C for 60 min. Over-500 nm-thickness CH3NH3PbI3-xBrx absorber layers were successfully obtained by sequential deposition routes using 1.7 M PbI2·DMSO complex precursor solution and 0.465 M isopropanol solution of the methylammonium halide mixture with the molar ratio of CH3NH3I/CH3NH3Br=85/15. The perovskite solar cells based on the TiO2 nanorod array and 560 nm-thickness CH3NH3PbI3-xBrx absorber layer exhibited the best photoelectric conversion efficiency (PCE) of 15.93%, while the corresponding planar perovskite solar cells without the TiO2 nanorod array and with 530 nm-thickness CH3NH3PbI3-xBrx absorber layer gave the best PCE of 12.82% at the relative humidity of 50-54%.

  3. FULL-LENGTH PEPTIDE ASSAY OF ANTIGENIC PROFILE OF ENVELOPE PROTEINS FROM SIBERIAN ISOLATES OF HEPATITIS C VIRUS

    Directory of Open Access Journals (Sweden)

    A. A. Grazhdantseva

    2010-01-01

    Full Text Available Antigenic profiles of envelope glycoproteins of hepatitis C virus presented by three genotypes 1b, 2a/2c and 3a, which are most widespread in the territory of Russia and, in particular, in Novosibirsk, were studied using a panel of overlapping synthetic peptides. It was shown that highly immunogenic peptide epitopes of Е1 and Е2 proteins common for all HCV genotypes, are located in amino acid positions 250-260, 315-325 (Е1 protein, 390-400 (hypervariable region 1, 430-440, and 680-690 (Е2 protein. The greatest inter-genotypic differences were recorded in positions 280-290, 410-430 and 520-540. A novel antigenic determinant was detected in the region of aa 280-290 of the Е1 protein which was typical only for HCV 2a/2c genotype. A broad variation in the boundaries for the most epitopes suggests a high variability of the Е1 and Е2 viral proteins; however, a similar repertoire of antibodies induced by different HCV genotypes indicates to an opportunity of designing a new generation of cross-reactive HCV vaccines based on mapping of the E1 and E2 antigenic regions.

  4. Space charge profiles in low density polyethylene samples containing a permittivity/conductivity gradient

    DEFF Research Database (Denmark)

    Bambery, K.R.; Fleming, R.J.; Holbøll, Joachim

    2001-01-01

    Laser induced pressure pulse space charge measurements were made on 1.5 mm thick plaques of high purity low density polyethylene equipped with vacuum-evaporated aluminium electrodes. Temperature differences up to 20 °C were maintained across the samples, which were subjected to dc fields up to 1.......5×107 V m-1. Current density was also measured as a function of temperature and field. Space charge due exclusively to the temperature gradient was detected, with density of order 0.01 C m-3. The activation energy associated with the transport of electrons through the bulk was calculated as 0.09 e...... were inferred by combining the space charge and current density measurements...

  5. Psuedo-3D, isodensity and density profiles from fiber optic output of a MACH-130 air shock

    International Nuclear Information System (INIS)

    Dittmore, C.H.; Glenn, H.D.

    1981-01-01

    A modified Voitenko compressor generated a Mach-130 air shock in an outlet pipe open to the atmosphere. Fiber optics transmitted luminosity associated with propagation of the air shock to an external display board, which was scanned with a high-speed streaking camera. We describe the computerized microdensitometer scanning technique for converting the film records to pseudo-3D, isodensity, and density profiles. The isodensity contours can be displayed using different colors to facilitate analysis. This technique can achieve resolutions of 1 ns and 2 μm. We give examples of the pseudo-3D, isodensity, and density profile plots for the experiment. The microdensitometer output was digitized for input to data display programs run on a CDC 7600. These results were used to provide submicrosecond accuracy for shock propagation over a 5 m of the outlet pipes. In addition, we obtained information about gas flow behind the shock front. Other current or possible applications for the technique are measurement of: target implosion in laser fusion, flash x-ray data in hydrodynamic and ballistic experiments, temperature profiles for high energy (> 10 5 K) gas dynamics, and dynamic events in weapons testing

  6. Improved fluid mixing and power density in reverse electrodialysis stacks with chevron-profiled membranes

    NARCIS (Netherlands)

    Pawlowski, Sylwin; Rijnaarts, Timon; Saakes, Michel; Nijmeijer, Kitty; Crespo, João G.; Velizarov, Svetlozar

    2017-01-01

    Spacer-less RED stacks using membranes with integrated spacer profiles have been investigated during the last years to eliminate the spacer shadow effect. The presence of spacers partially blocks the membrane surface and creates a tortuous and thus longer path for ions in the channel, meaning higher

  7. Role of substituents on the reactivity and electron density profile of ...

    Indian Academy of Sciences (India)

    Theoretical descriptors using conceptual density functional theory have been used ... of these diimines will be studied within the framework of Frozen Core Approximation (FCA). The reliability of FCA has been already discussed by Kulkarni et al. in analysing the ligand characteristics.27d. The present paper has been ...

  8. Visualization and analysis of pulsed ion beam energy density profile with infrared imaging

    Science.gov (United States)

    Isakova, Y. I.; Pushkarev, A. I.

    2018-03-01

    Infrared imaging technique was used as a surface temperature-mapping tool to characterize the energy density distribution of intense pulsed ion beams on a thin metal target. The technique enables the measuring of the total ion beam energy and the energy density distribution along the cross section and allows one to optimize the operation of an ion diode and control target irradiation mode. The diagnostics was tested on the TEMP-4M accelerator at TPU, Tomsk, Russia and on the TEMP-6 accelerator at DUT, Dalian, China. The diagnostics was applied in studies of the dynamics of the target cooling in vacuum after irradiation and in the experiments with target ablation. Errors caused by the target ablation and target cooling during measurements have been analyzed. For Fluke Ti10 and Fluke Ti400 infrared cameras, the technique can achieve surface energy density sensitivity of 0.05 J/cm2 and spatial resolution of 1-2 mm. The thermal imaging diagnostics does not require expensive consumed materials. The measurement time does not exceed 0.1 s; therefore, this diagnostics can be used for the prompt evaluation of the energy density distribution of a pulsed ion beam and during automation of the irradiation process.

  9. The improved DGR analytical model of electron density height profile and total electron content in the ionosphere

    OpenAIRE

    Radicella, S. M.; Zhang, M. L.

    1995-01-01

    Tests of the analytical model of the electron density profile originally proposed by G, Di Giovanni and S.M. Radicella (DGR model) have shown the need to introduce improvements in order to obtain a model able to reproduce the ionosphere in a larger spectrum of geophysical and time conditions. The present paper reviews the steps toward such progress and presents the final formulation of the model. It gives also a brief re- view of tests of the improved model done by different authors.

  10. Transcriptomic Profiling of High-Density Giardia Foci Encysting in the Murine Proximal Intestine.

    Science.gov (United States)

    Pham, Jonathan K; Nosala, Christopher; Scott, Erica Y; Nguyen, Kristofer F; Hagen, Kari D; Starcevich, Hannah N; Dawson, Scott C

    2017-01-01

    Giardia is a highly prevalent, understudied protistan parasite causing significant diarrheal disease worldwide. Its life cycle consists of two stages: infectious cysts ingested from contaminated food or water sources, and motile trophozoites that colonize and attach to the gut epithelium, later encysting to form new cysts that are excreted into the environment. Current understanding of parasite physiology in the host is largely inferred from transcriptomic studies using Giardia grown axenically or in co-culture with mammalian cell lines. The dearth of information about the diversity of host-parasite interactions occurring within distinct regions of the gastrointestinal tract has been exacerbated by a lack of methods to directly and non-invasively interrogate disease progression and parasite physiology in live animal hosts. By visualizing Giardia infections in the mouse gastrointestinal tract using bioluminescent imaging (BLI) of tagged parasites, we recently showed that parasites colonize the gut in high-density foci. Encystation is initiated in these foci throughout the entire course of infection, yet how the physiology of parasites within high-density foci in the host gut differs from that of cells in laboratory culture is unclear. Here we use BLI to precisely select parasite samples from high-density foci in the proximal intestine to interrogate in vivo Giardia gene expression in the host. Relative to axenic culture, we noted significantly higher expression (>10-fold) of oxidative stress, membrane transporter, and metabolic and structural genes associated with encystation in the high-density foci. These differences in gene expression within parasite foci in the host may reflect physiological changes associated with high-density growth in localized regions of the gut. We also identified and verified six novel cyst-specific proteins, including new components of the cyst wall that were highly expressed in these foci. Our in vivo transcriptome data support an

  11. Water Quality and Sediment Profile in Shrimp Culture with Different Sediment Redox Potential and Stocking Densities Under Laboratory Condition

    Directory of Open Access Journals (Sweden)

    Wiyoto Wiyoto

    2016-06-01

    Full Text Available Sediment quality has been considered as one of the prime factors influencing the environment quality that support maximum shrimp production.The aim of the study was toevaluate the effects of sediment redox potential and shrimp stocking density on the profile of some sediment and water quality parameters. Two factors randomized factorial design was applied, with stocking density (60 and 120 shrimps.m-2 as the first variable and sediment redox potential (-65 mV, -108 mV and -206 mV as the second variable. Some significant changes in TP, total Mn, and total S concentrations in the sediment were observed after the experimentation (P<0.05. Sediment redox potential significantly affected the dissolved oxygen, TAN, NO2, NO3, and H2S concentrations in the water. Whereas shrimp stocking density affected all water quality parameters except H2S concentration. Significant interactions between redox potential and stocking densities were observed in the nitrite and alkalinity concentrations. The significant effects of both shrimp density and redox potential on the sediment and water parameters in particular those that are known to directly affect the shrimp welfare (e.g. oxygen, ammonia, nitrite and H2S indicate that these variables are of important aspects in shrimp pond management. Furthermore, the results clearly showed that -206mV redox potential significantly reduced the dissolved oxygen concentration in the sediment-water interface and increased the generation of H2S in water column. Thereby, this redox potential level is not advisable for shrimp culture system. Keywords: redox potential, stocking density.

  12. Core and Wing Densities of Asymmetric Coronal Spectral Profiles: Implications for the Mass Supply of the Solar Corona

    Science.gov (United States)

    Patsourakos, S.; Klimchuk, J. A.; Young, P. R.

    2014-01-01

    Recent solar spectroscopic observations have shown that coronal spectral lines can exhibit asymmetric profiles, with enhanced emissions at their blue wings. These asymmetries correspond to rapidly upflowing plasmas at speeds exceeding approximately equal to 50 km per sec. Here, we perform a study of the density of the rapidly upflowing material and compare it with that of the line core that corresponds to the bulk of the plasma. For this task, we use spectroscopic observations of several active regions taken by the Extreme Ultraviolet Imaging Spectrometer of the Hinode mission. The density sensitive ratio of the Fe(sub XIV) lines at 264.78 and 274.20 Angstroms is used to determine wing and core densities.We compute the ratio of the blue wing density to the core density and find that most values are of order unity. This is consistent with the predictions for coronal nanoflares if most of the observed coronal mass is supplied by chromospheric evaporation driven by the nanoflares. However, much larger blue wing-to-core density ratios are predicted if most of the coronal mass is supplied by heated material ejected with type II spicules. Our measurements do not rule out a spicule origin for the blue wing emission, but they argue against spicules being a primary source of the hot plasma in the corona. We note that only about 40% of the pixels where line blends could be safely ignored have blue wing asymmetries in both Fe(sub XIV) lines. Anticipated sub-arcsecond spatial resolution spectroscopic observations in future missions could shed more light on the origin of blue, red, and mixed asymmetries.

  13. Improvement of Lipid Profile Is Accompanied by Atheroprotective Alterations in High-Density Lipoprotein Composition Upon Tumor Necrosis Factor Blockade A Prospective Cohort Study in Ankylosing Spondylitis

    NARCIS (Netherlands)

    Eijk, van I.C.; Vries, de M.K.; Levels, J.H.M.; Peters, M.J.L.; Huizer, E.E.; Dijkmans, B.A.C.; Horst - Bruinsma, van der I.E.; Hazenberg, B.P.C.; Stadt, van de R.J.; Wolbink, G.; Nurmohamed, M.T.

    2009-01-01

    Objective. Cardiovascular mortality is increased in ankylosing spondylitis (AS), and inflammation plays an important role. Inflammation deteriorates the lipid profile and alters high-density lipoprotein cholesterol (HDL-c) composition, reflected by increased concentrations of serum amyloid A (SAA)

  14. Recreational football improves bone mineral density and bone turnover marker profile in elderly men

    DEFF Research Database (Denmark)

    Helge, Eva Wulff; Rostgaard Andersen, Thomas; Schmidt, Jakob Friis

    2014-01-01

    This study examined the effect of recreational football and resistance training on bone mineral density (BMD) and bone turnover markers (BTMs) in elderly men. Twenty-six healthy sedentary men (age 68.2 ± 3.2 years) were randomized into three groups: football (F; n = 9) and resistance training (R; n...... training had no effect. The anabolic response may be due to increased bone turnover, especially improved bone formation....

  15. Correlated magnetic impurities in a superconductor: electron density profiles and robustness of superconductivity.

    Science.gov (United States)

    Sacramento, P D; Dugaev, V K; Vieira, V R; Araújo, M A N

    2010-01-20

    The insertion of magnetic impurities in a conventional superconductor leads to various effects. In this work we show that the electron density is affected by the spins (considered as classical) both locally and globally. The charge accumulation is solved self-consistently. This affects the transport properties along magnetic domain walls. Also, we show that superconductivity is more robust if the spin locations are not random but correlated. © 2010 IOP Publishing Ltd

  16. Sub-millisecond electron density profile measurement at the JET tokamak with the fast lithium beam emission spectroscopy system

    Science.gov (United States)

    Réfy, D. I.; Brix, M.; Gomes, R.; Tál, B.; Zoletnik, S.; Dunai, D.; Kocsis, G.; Kálvin, S.; Szabolics, T.; JET Contributors

    2018-04-01

    Diagnostic alkali atom (e.g., lithium) beams are routinely used to diagnose magnetically confined plasmas, namely, to measure the plasma electron density profile in the edge and the scrape off layer region. A light splitting optics system was installed into the observation system of the lithium beam emission spectroscopy diagnostic at the Joint European Torus (JET) tokamak, which allows simultaneous measurement of the beam light emission with a spectrometer and a fast avalanche photodiode (APD) camera. The spectrometer measurement allows density profile reconstruction with ˜10 ms time resolution, absolute position calculation from the Doppler shift, spectral background subtraction as well as relative intensity calibration of the channels for each discharge. The APD system is capable of measuring light intensities on the microsecond time scale. However ˜100 μs integration is needed to have an acceptable signal to noise ratio due to moderate light levels. Fast modulation of the beam up to 30 kHz is implemented which allows background subtraction on the 100 μs time scale. The measurement covers the 0.9 localized modes.

  17. Interspecies Interactions in Relation to Root Distribution Across the Rooting Profile in Wheat-Maize Intercropping Under Different Plant Densities

    Directory of Open Access Journals (Sweden)

    Yifan Wang

    2018-04-01

    Full Text Available In wheat-maize intercropping systems, the maize is often disadvantageous over the wheat during the co-growth period. It is unknown whether the impaired growth of maize can be recovered through the enhancement of the belowground interspecies interactions. In this study, we (i determined the mechanism of the belowground interaction in relation to root growth and distribution under different maize plant densities, and (ii quantified the “recovery effect” of maize after wheat harvest. The three-year (2014–2016 field experiment was conducted at the Oasis Agriculture Research Station of Gansu Agricultural University, Wuwei, Northwest China. Root weight density (RWD, root length density (RLD, and root surface area density (RSAD, were measured in single-cropped maize (M, single-cropped wheat (W, and three intercropping systems (i wheat-maize intercropping with no root barrier (i.e., complete belowground interaction, IC, (ii nylon mesh root barrier (partial belowground interaction, IC-PRI, and (iii plastic sheet root barrier (no belowground interaction, IC-NRI. The intercropped maize was planted at low (45,000 plants ha−1 and high (52,000 plants ha−1 densities. During the wheat/maize co-growth period, the IC treatment increased the RWD, RLD, and RSAD of the intercropped wheat in the 20–100 cm soil depth compared to the IC-PRI and IC-NRI systems; intercropped maize had 53% lower RWD, 81% lower RLD, and 70% lower RSAD than single-cropped maize. After wheat harvest, the intercropped maize recovered the growth with the increase of RWD by 40%, RLD by 44% and RSAD by 11%, compared to the single-cropped maize. Comparisons among the three intercropping systems revealed that the “recovery effect” of the intercropped maize was attributable to complete belowground interspecies interaction by 143%, the compensational effect due to root overlap by 35%, and the compensational effect due to water and nutrient exchange (CWN by 80%. The higher maize plant

  18. Density profile evolution and nonequilibrium effects in partial and full spreading measurements of surface diffusion

    DEFF Research Database (Denmark)

    Nikunen, P.; Vattulainen, Ilpo Tapio; Ala-Nissila, T.

    2001-01-01

    in D-C(theta) depend on the initial density gradient and the initial state from which the spreading starts. To this end, we carry out extensive Monte Carlo simulations for a lattice-gas model of the O/W(110) system. Studies of submonolayer spreading from an initially ordered p(2x1) phase at theta = 1....../2 reveal that the spreading and diffusion rates in directions parallel and perpendicular to rows of oxygen atoms are significantly different within the ordered phase. Aside from this effect, we find that the degree of ordering in the initial phase has a relatively small impact on the overall behavior of D...

  19. Density profile in shock wave fronts of partially ionized xenon plasmas

    CERN Document Server

    Reinholz, H; Morozov, I; Mintsev, V; Zaparoghets, Y; Fortov, V; Wierling, A

    2003-01-01

    Results for the reflection coefficient of shock-compressed dense xenon plasmas at pressures of 1.6-20 GPa and temperatures around 30 000 K are interpreted. In addition to former experiments using laser beams with lambda = 1.06 mu m, measurements at lambda = 0.694 mu m have been performed recently. Reflectivities typical for metallic systems are found at high densities. Besides free carriers, the theoretical description also takes into account the influence of the neutral component of the plasma on the reflectivity. A consistent description of the measured reflectivities is achieved only if a finite width of the shock wave front is considered.

  20. Radio occultation electron density profiles from the FORMOSAT-3/COSMIC satellites over the Brazilian region: A comparison with Digisonde data

    Science.gov (United States)

    Ely, C. V.; Batista, I. S.; Abdu, M. A.

    2012-06-01

    This study aims to validate the electron density profiles from the FORMOSAT-3/COSMIC satellites with data from Digisondes in Brazil during the low solar activity period of the years 2006, 2007 and 2008. Data from three Brazilian Digisondes located in Cachoeira Paulista (22.7°S, 45°W), São Luís (2.5°S, 44.2°W) and Fortaleza (3.8°S, 38°W) were used in the comparisons. Only the profiles whose density peak have been obtained near the stations coordinates were chosen for the comparison. Although there is generally good agreement, some cases of discrepancies are observed. Some of these discrepancies cannot be explained simply by the differences in the position and local time of the measurements made by the satellite and the ground-based station. In such cases it is possible that local conditions, such as the presence of a trans-equatorial wind or electron density gradients, could contribute to the observed differences. Comparison of the F2 layer peak parameters, the NmF2 and hmF2, obtained from the two techniques showed that, in general, the agreement for NmF2 is pretty good and the NmF2 has a better correlation than hmF2. Cachoeira Paulista had the worst correlation for hmF2 possibly because this station is situated in the region under the influence of the equatorial ionization anomaly, a region where it is more difficult to apply the RO technique without violating the spherical symmetry condition.

  1. Spatial profiles of electron and metastable atom densities in positive polarity fast ionization waves sustained in helium

    International Nuclear Information System (INIS)

    Weatherford, Brandon R.; Barnat, E. V.; Xiong, Zhongmin; Kushner, Mark J.

    2014-01-01

    Fast ionization waves (FIWs), often generated with high voltage pulses over nanosecond timescales, are able to produce large volumes of ions and excited states at moderate pressures. The mechanisms of FIW propagation were experimentally and computationally investigated to provide insights into the manner in which these large volumes are excited. The two-dimensional structure of electron and metastable densities produced by short-pulse FIWs sustained in helium were measured using laser-induced fluorescence and laser collision-induced fluorescence diagnostics for times of 100–120 ns after the pulse, as the pressure was varied from 1 to 20 Torr. A trend of center-peaked to volume-filling to wall-peaked electron density profiles was observed as the pressure was increased. Instantaneous FIW velocities, obtained from plasma-induced emission, ranged from 0.1 to 3 × 10 9  cm s −1 , depending on distance from the high voltage electrode and pressure. Predictions from two-dimensional modeling of the propagation of a single FIW correlated well with the experimental trends in electron density profiles and wave velocity. Results from the model show that the maximum ionization rate occurs in the wavefront, and the discharge continues to propagate forward after the removal of high voltage from the powered electrode due to the potential energy stored in the space charge. As the pressure is varied, the radial distribution of the ionization rate is shaped by changes in the electron mean free path, and subsequent localized electric field enhancement at the walls or on the centerline of the discharge.

  2. Profile of cortisol, glycaemia, and blood parameters of American Bullfrog tadpoles Lithobates catesbeianus exposed to density and hypoxia stressors

    Directory of Open Access Journals (Sweden)

    Patricia C. Teixeira

    2012-12-01

    Full Text Available The aim of this study was to evaluate alterations to the physiological profile (cortisol, glycaemia, and blood parameters of Lithobates catesbeianus caused by the stressors density and hypoxia. The organisms were in the prometamorphosis stage and exposed to different tadpole densities: 1 tadpole/L (T1, 5 tadpoles/L (T2, and 10 tadpoles/L (T3 for 12 days. The blood was collected through the rupture of the caudal blood vessel and collected under normoxia (immediate collection and hypoxia (after 15 minutes of air exposure conditions. Cortisol levels rose on the fourth and eighth days of treatment and returned to basal levels by the end of the experiment. The stressor mechanisms tested did not affect glycaemia. White blood cells (total number of lymphocytes, neutrophils, and eosinophils showed a significant difference at the twelfth day of the experiment when compared with the start of the experiment. We concluded that, under controlled conditions, a density of up to 10 tadpoles/L and air exposure for 15 minutes did not cause harmful physiological alterations during the experimental period. The answer to these stressors maybe was in another hormonal level (corticosterone.

  3. The control of plasma density profile in Tore Supra. Comparison of different fueling techniques

    International Nuclear Information System (INIS)

    Commaux, N.

    2007-09-01

    The behaviour of a reactor-class plasma when fuelled using the existing techniques (gas puffing, supersonic molecular beam injection and pellet injection) is still very difficult to foresee. The present work has been initiated on Tore Supra in order to extrapolate the consequences of the different fuelling systems on ITER. Two main topics have been studied: the comparison of the plasma behaviour when fuelled using the different techniques at high Greenwald density fractions and the study of the homogenization following a pellet injection (main fuelling technique for ITER burning plasmas). The experiments at high Greenwald density fractions performed on Tore Supra showed that the plasma behaviour is very dependent on the fuelling method. The plasma energy confinement is following the scaling laws determined at low density when fuelled using pellet injection. which is better than for gas puffing and SMBI. both inducing a significant confinement loss. This behaviour is nor related to a transport modification: the ratio between effective diffusion and convection is similar to the pellet case. The difference between these shots is related only to the position of the matter source (at the edge for gas and close to the center for pellets). The study concerning the homogenization phenomena following a pellet injection aims mainly to study the ∇B-drift effect that expels the mater deposited by a pellet toward the low field side. A new phenomenon. which appears to be particularly important for the ∇B-drift during low field side injections. was then discovered: the influence of magnetic surfaces with an integer-valued safety factor (q). When the mater drifting toward low field side crosses an integer q surface. it experiences an important braking effect which stops the drift motion. It implies that the pellet material is mainly deposited on the last integer q surface crossed by the pellet during its injection. This study allows also to determine that the

  4. Lipid, fatty acid and energy density profiles of white sharks: insights into the feeding ecology and ecophysiology of a complex top predator.

    Science.gov (United States)

    Pethybridge, Heidi R; Parrish, Christopher C; Bruce, Barry D; Young, Jock W; Nichols, Peter D

    2014-01-01

    Lipids are major sources of metabolic energy in sharks and are closely linked to environmental conditions and biological cycles, such as those related to diet, reproduction and migration. In this study, we report for the first time, the total lipid content, lipid class composition and fatty acid profiles of muscle and liver tissue of white sharks, Carcharodon carcharias, of various lengths (1.5-3.9 m), sampled at two geographically separate areas off southern and eastern Australia. Muscle tissue was low in total lipid content (90% of total lipid) and polyunsaturated fatty acids (34±12% of total fatty acids). In contrast, liver was high in total lipid which varied between 51-81% wm and was dominated by triacylglycerols (>93%) and monounsaturated fatty acids (36±12%). With knowledge of total lipid and dry tissue mass, we estimated the energy density of muscle (18.4±0.1 kJ g-1 dm) and liver (34.1±3.2 kJ g-1 dm), demonstrating that white sharks have very high energetic requirements. High among-individual variation in these biochemical parameters and related trophic markers were observed, but were not related to any one biological or environmental factor. Signature fatty acid profiles suggest that white sharks over the size range examined are generalist predators with fish, elasmobranchs and mammalian blubber all contributing to the diet. The ecological applications and physiological influences of lipids in white sharks are discussed along with recommendations for future research, including the use of non-lethal sampling to examine the nutritional condition, energetics and dietary relationships among and between individuals. Such knowledge is fundamental to better understand the implications of environmental perturbations on this iconic and threatened species.

  5. Time Ordering Effects on Hydrogen Zeeman-Stark Line Profiles in Low-Density Magnetized Plasmas

    Directory of Open Access Journals (Sweden)

    J. Rosato

    2010-01-01

    Full Text Available Stark broadening of hydrogen lines is investigated in low-density magnetized plasmas, at typical conditions of magnetic fusion experiments. The role of time ordering is assessed numerically, by using a simulation code accounting for the evolution of the microscopic electric field generated by the charged particles moving at the vicinity of the atom. The Zeeman effect due to the magnetic field is also retained. Lyman lines with a low principal quantum number n are first investigated, for an application to opacity calculations; next Balmer lines with successively low and high principal quantum numbers are considered for diagnostic purposes. It is shown that neglecting time ordering results in a dramatic underestimation of the Stark effect on the low-n lines. Another conclusion is that time ordering becomes negligible only when ion dynamics effects vanish, as shown in the case of high-n lines.

  6. Using X-mode L, R and O-mode reflectometry cutoffs to measure scrape-off-layer density profiles for upgraded ORNL reflectometer on NSTX-U.

    Science.gov (United States)

    Lau, C; Wilgen, J B; Caughman, J B; Hanson, G R; Hosea, J; Perkins, R; Ryan, P M; Taylor, G

    2014-11-01

    The pre-existing ORNL scrape-off-layer (SOL) reflectometer that operated with the X-mode R-cutoff at 6-27 GHz to measure SOL density profiles on NSTX is being upgraded to be functional at the increased magnetic fields on NSTX-U spherical tokamak. Rather than increasing the operating frequencies to measure the higher X-mode R-cutoff frequencies on NSTX-U, it will be shown that the combined use of the X-mode R, L and O-mode cutoffs at 6-27 GHz can obtain the desired SOL density profiles. The potential capabilities and obstacles of this technique to measure SOL density profiles and possibly SOL magnetic field profiles on NSTX-U will be discussed.

  7. Determination of density profiles of unevenly compressed wood of Po­pu­lus tremula using the X – RAY DENSE – LAB laboratory device

    Directory of Open Access Journals (Sweden)

    Aleš Dejmal

    2009-01-01

    Full Text Available The paper deals with the measuring of the density profile of unevenly pressed wood of European aspen (Populus tremula L.. The main aim of the work is to examine in an experimental way the possibilities of using the X – RAY DENSE – LAB laboratory equipment designed for the determination of density profiles of agglomerated and plied large-area materials. The work uses the X – RAY DENSE – LAB equipment to determine the density profile of the cross-section of unevenly pressed aspen wood, plasticized hydrothermically, without the presence of chemical substances. The work also presents calculations of the level of compression/densification in dependence on the density and it describes the factors that can influence the density profile of compressed/densified wood; at the same time, it presents the possible ways to determine the density profile in the cross-section. Further, it includes the creation of the methodology for sample preparation so that the results do not get distorted during measuring. It describes the preparation of sample pieces, the orientation of the anatomic structure, the methodology of pressing, air conditioning, sample preparation, their measuring and analysis. The paper also describes the theory and the principles of measuring with use of X – RAY DENSE – LAB and its calibration. The paper analyses the obtained results of density profiles and searches for and describes the causes of the uneven distribution of the density in the cross-section. It concludes by summarizing the results and recommending the procedure for future measuring.

  8. Finite length thermal equilibria of a pure electron plasma column

    International Nuclear Information System (INIS)

    Prasad, S.A.; O'Neil, T.M.

    1979-01-01

    The electrons of a pure electron plasma may be in thermal equilibrium with each other and still be confined by static magnetic and electric fields. Since the electrons make a significant contribution to the electric field, only certain density profiles are consistent with Poisson's equation. The class of such distributions for a finite length cylindrical column is investigated. In the limit where the Debye length is small compared with the dimensions of the column, the density is essentially constant out to some surface of revolution and then falls off abruptly. The falloff in density is a universal function when measured along the local normal to the surface of revolution and scaled in terms of the Debye length. The solution for the shape of the surface of revolution is simplified by passage to the limit of zero Debye length

  9. Transcription profiling of the early gravitropic response in Arabidopsis using high-density oligonucleotide probe microarrays

    Science.gov (United States)

    Moseyko, Nick; Zhu, Tong; Chang, Hur-Song; Wang, Xun; Feldman, Lewis J.

    2002-01-01

    Studies of plant tropisms, the directed growth toward or away from external stimuli such as light and gravity, began more than a century ago. Yet biochemical, physiological, and especially molecular mechanisms of plant tropic responses remain for the most part unclear. We examined expression of 8,300 genes during early stages of the gravitropic response using high-density oligonucleotide probe microarrays. Approximately 1.7% of the genes represented on the array exhibited significant expression changes within the first 30 min of gravity stimulation. Among gravity-induced genes were a number of genes previously implicated to be involved in gravitropism. However, a much larger number of the identified genes have not been previously associated with gravitropism. Because reorientation of plants may also expose plants to mechanical perturbations, we also compared the effects of a gentle mechanical perturbation on mRNA levels during the gravity response. It was found that approximately 39% of apparently gravity-regulated genes were also regulated by the mechanical perturbation caused by plant reorientation. Our study revealed the induction of complex gene expression patterns as a consequence of gravitropic reorientation and points to an interplay between the gravitropic and mechanical responses and to the extreme sensitivity of plants to even very gentle mechanical perturbations.

  10. Measurement of Pion and Proton Response and Longitudinal Shower Profiles up to 20 Nuclear Interaction Lengths with the ATLAS Tile Calorimeter

    CERN Document Server

    Adragna, P; Anderson, K; Antonaki, A; Arabidze, A; Batkova, L; Batusov, V; Beck, H P; Bergeaas Kuutmann, E; Biscarat, C; Blanchot, G; Bogush, A; Bohm, C; Boldea, V; Bosman, M; Bromberg, C; Budagov, J; Burckhart-Chromek, D; Caprini, M; Caloba, L; Calvet, D; Carli, T; Carvalho, J; Cascella, M; Castelo, J; Castillo, M V; Cavalli-Sforza, M; Cavasinni, V; Cerqueira, A S; Clement, C; Cobal, M; Cogswell, F; Constantinescu, S; Costanzo, D; Corso-Radu, A; Cuenca, C; Damazio, D O; Davidek, T; De, K; Del Prete, T; Di Girolamo, B; Dita, S; Djobava, T; Dobson, M; Dotti, A; Downing, R; Efthymiopoulos, I; Eriksson, D; Errede, D; Errede, S; Farbin, A; Fassouliotis, D; Febbraro, R; Fenyuk, A; Ferdi, C; Ferrer, A; Flaminio, V; Francis, D; Fullana, E; Gadomski, S; Gameiro, S; Garde, V; Gellerstedt, K; Giakoumopoulou, V; Gildemeister, O; Gilewsky, V; Giokaris, N; Gollub, N; Gomes, A; Gonzalez, V; Gorini, B; Grenier, P; Gris, P; Gruwe, M; Guarino, V; Guicheney, C; Gupta, A; Haeberli, C; Hakobyan, H; Haney, M; Hellman, S; Henriques, A; Higon, E; Holmgren, S; Hurwitz, M; Huston, J; Iglesias, C; Isaev, A; Jen-La Plante, I; Jon-And, K; Joos, M; Junk, T; Karyukhin, A; Kazarov, A; Khandanyan, H; Khramov, J; Khubua, J; Kolos, S; Korolkov, I; Krivkova, P; Kulchitsky, Y; Kurochkin, Yu; Kuzhir, P; LeCompte, T; Lefevre, R; Lehmann, G; Leitner, R; Lembesi, M; Lesser, J; Li, J; Liablin, M; Lokajicek, M; Lomakin, Y; Lupi, A; Maidanchik, C; Maio, A; Makouski, M; Maliukov, S; Manousakis, A; Mapelli, L; Marques, C; Marroquim, F; Martin, F; Mazzoni, E; Merritt, F; Miagkov, A; Miller, R; Minashvili, I; Miralles, L; Montarou, G; Mosidze, M; Myagkov, A; Nemecek, S; Nessi, M; Nodulman, L; Nordkvist, B; Norniella, O; Novakova, J; Onofre, A; Oreglia, M; Pallin, D; Pantea, D; Petersen, J; Pilcher, J; Pina, J; Pinhao, J; Podlyski, F; Portell Bueso, X; Poveda, J; Pribyl, L; Price, L E; Proudfoot, J; Ramstedt, M; Richards, R; Roda, C; Romanov, V; Rosnet, P; Roy, P; Ruiz, A; Rumiantsev, V; Russakovich, N; Salto, O; Salvachua, B; Sanchis, E; Sanders, H; Santoni, C; Saraiva, J G; Sarri, F; Satsunkevitch, I; Says, L P; Schlager, G; Schlereth, J; Seixas, J M; Sellden, B; Shalanda, N; Shevtsov, P; Shochet, M; Silva, J; Da Silva, P; Simaitis, V; Simonyan, M; Sissakian, A; Sjolin, J; Solans, C; Solodkov, A; Soloviev, I; Solovyanov, O; Sosebee, M; Spano, F; Stanek, R; Starchenko, E; Starovoitov, P; Stavina, P; Suk, M; Sykora, I; Tang, F; Tas, P; Teuscher, R; Tokar, S; Topilin, N; Torres, J; Tremblet, L; Tsiareshka, P; Tylmad, M; Underwood, D; Unel, G; Usai, G; Valero, A; Valkar, S; Valls, J A; Vartapetian, A; Vazeille, F; Vichou, I; Vinogradov, V; Vivarelli, I; Volpi, M; White, A; Zaitsev, A; Zenine, A; Zenis, T

    2010-01-01

    The response of pions and protons in the energy range of 20 to 180 GeV produced at CERN's SPS H8 test beam line in the ATLAS iron-scintillator Tile hadron calorimeter has been measured. The test-beam configuration allowed to measure the longitudinal shower development for pions and protons up to 20 nuclear interaction lengths. It is found that pions penetrate deeper in the calorimeter than protons. However, protons induce showers that are wider laterally to the direction of the impinging particle. Including the measured total energy response, the pion to proton energy ratio and the resolution, all observations are consistent with a higher electromagnetic energy fraction in pion induced showers. The data are compared with GEANT4 simulations using several hadronic physics lists. The measured longitudinal shower profiles are described by an analytical shower parameterization within an accuracy of 5-10%. The amount of energy leaking out behind the calorimeter is determined and parameterised as a function of the b...

  11. Identifying the 630 nm auroral arc emission height: A comparison of the triangulation, FAC profile, and electron density methods

    Science.gov (United States)

    Megan Gillies, D.; Knudsen, D.; Donovan, E.; Jackel, B.; Gillies, R.; Spanswick, E.

    2017-08-01

    We present a comprehensive survey of 630 nm (red-line) emission discrete auroral arcs using the newly deployed Redline Emission Geospace Observatory. In this study we discuss the need for observations of 630 nm aurora and issues with the large-altitude range of the red-line aurora. We compare field-aligned currents (FACs) measured by the Swarm constellation of satellites with the location of 10 red-line (630 nm) auroral arcs observed by all-sky imagers (ASIs) and find that a characteristic emission height of 200 km applied to the ASI maps gives optimal agreement between the two observations. We also compare the new FAC method against the traditional triangulation method using pairs of all-sky imagers (ASIs), and against electron density profiles obtained from the Resolute Bay Incoherent Scatter Radar-Canadian radar, both of which are consistent with a characteristic emission height of 200 km.

  12. Defining the bone morphometry, micro-architecture and volumetric density profile in osteopenic vs non-osteopenic adolescent idiopathic scoliosis.

    Science.gov (United States)

    Wang, Zhi-Wei; Lee, Wayne Yuk-Wai; Lam, Tsz-Ping; Yip, Benjamin Hon-Kei; Yu, Fiona Wai-Ping; Yu, Wing-Sze; Zhu, Feng; Ng, Bobby Kin-Wah; Qiu, Yong; Cheng, Jack Chun-Yiu

    2017-06-01

    Osteopenia has been widely reported in about 30 % of girls with adolescent idiopathic scoliosis (AIS). However, the bone quality profile of the 70 % non-osteopenic AIS defined by areal bone mineral density (BMD) with conventional dual-energy X-ray absorptiometry (DXA) has not been adequately studied. Our purpose was to verify whether abnormal volumetric BMD (vBMD) and bone structure (morphometry and micro-architecture) also existed in the non-osteopenic AIS when compared with matched controls using both DXA and high-resolution peripheral computed tomography (HR-pQCT). This was a case-control cross-sectional study. 257 AIS girls with a mean age of 12.7 (SD = 0.8) years old and 187 age- and gender-matched normal controls with an average age of 12.9 (SD = 0.5) years old were included. Areal BMD (aBMD) and bone quality were measured with standard DXA and HR-pQCT, respectively. The parameters of HR-pQCT could be categorized as bone morphometry, vBMD and bone micro-architecture. The results were compared between the osteopenic AIS and osteopenic control, and between the non-osteopenic AIS and non-osteopenic control. In addition to the lower aBMD and vBMD, osteopenic AIS showed significantly greater cortical perimeter and trabecular area than the osteopenic control even after adjustments of age (P architecture and volumetric density profile compared with their normal matched controls. The observed abnormalities were suggestive of decreased endocortical bone apposition or active endocortical resorption that could affect the mechanical bone strength in AIS. The underlying pathomechanism might be attributed to abnormal bone modeling/remodeling that could be associated with the etiopathogenesis of AIS.

  13. Vitamin D is associated with atheroprotective high-density lipoprotein profile in postmenopausal women

    Science.gov (United States)

    Kazlauskaite, Rasa; Powell, Lynda H.; Mandapakala, Chaitanya; Cursio, John F.; Avery, Elizabeth F.; Calvin, James

    2012-01-01

    BACKGROUND Low vitamin D has been associated with low levels of high-density lipoprotein (HDL) cholesterol, a marker of coronary risk. Whether atheroprotective HDL particle composition accounts for this association and whether fat affects this association is not known. OBJECTIVE To explore the association between HDL particle composition and 25-hydroxy vitamin D (25[OH]D) in post-menopausal women. METHODS Vitamin D levels and lipoprotein composition were assessed in fasting blood samples of apparently healthy women from a diverse Chicago community. Visceral (VAT) and subcutaneous (SAT) abdominal fat area were assessed using computed tomography. Total body fat mass was measured by dual-energy X-ray absorptiometry. RESULTS We enrolled 78 women (50% black; 50% white), age 48 to 64 years, all of whom were participants in a longitudinal study of fat patterning. They had a mean 25[OH]D of 31 ± 15 µg/L, HDL cholesterol 57 ± 11 mg/dL, and large HDL particle subclass 8.6 ± 3.4 µmol/L. In a multivariable-adjusted regression model, each 5 µg/L higher 25[OH]D predicted 0.57 µmol/L (95%CI 0.20–0.95) higher large HDL particles, independent of race, season, and total HDL particle concentration. This association was only partially confounded by total body fat mass (0.49, 95%CI 0.10–0.89), SAT (0.50, 95%CI 0.11–0.90), or VAT (0.37, 95%CI 0.01–0.74). Age did not significantly influence the strength of associations. CONCLUSIONS Higher 25[OH]D levels are associated with large HDL particles. This association is stronger than that of HDL cholesterol and only partially confounded by body fat. Theoretically, vitamin D may protect against cardiovascular risk by promoting formation of large HDL particles, affecting reverse cholesterol transport. PMID:21122638

  14. An investigation of magnetic field effects on plume density and temperature profiles of an applied-field MPD thruster

    Science.gov (United States)

    Bullock, S. Ray; Myers, R. M.

    1994-01-01

    Applied-field magnetoplasmadynamic (MPD) thruster performance is below levels required for primary propulsion missions. While MPD thruster performance has been found to increase with the magnitude of the applied-field strength, there is currently little understanding of the impact of applied-field shape on thruster performance. The results of a study in which a single applied-field thruster was operated using three solenoidal magnets with diameters of 12.7, 15.2, and 30.4-cm are presented. Thruster voltage and anode power deposition were measured for each applied field shape over a range of field strengths. Plume electron number density and temperature distributions were measured using a Langmuir probe in an effort to determine the effect of field shape on plume confinement by the diverging magnetic-field for each of the three magnetic field shapes. Results show that the dependence of the measured thruster characteristics on field shape were non-monotonic and that the field shape had a significant effect on the plume density and temperature profiles.

  15. Improving the AGR Fuel Testing Power Density Profile Versus Irradiation-Time in the Advanced Test Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Gray S. Chang; David A. Petti; John T. Maki; Misti A. Lillo

    2009-05-01

    The Very High Temperature gas-cooled Reactor (VHTR), which is currently being developed, achieves simplification of safety through reliance on ceramic-coated fuel particles. Each TRISO-coated fuel particle has its own containment which serves as the principal barrier against radionuclide release under normal operating and accident conditions. These fuel particles, in the form of graphite fuel compacts, are currently undergoing a series of irradiation tests in the Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL) to support the Advanced Gas-Cooled Reactor (AGR) fuel qualification program. A representive coated fuel particle with an 235U enrichment of 19.8 wt% was used in this analysis. The fuel burnup analysis tool used to perform the neutronics study reported herein, couples the Monte Carlo transport code MCNP, with the radioactive decay and burnup code ORIGEN2. The fuel burnup methodology known as Monte-Carlo with ORIGEN2 (MCWO) was used to evaluate the AGR experiment assembly and demonstrate compliance with ATR safety requirements. For the AGR graphite fuel compacts, the MCWO-calculated fission power density (FPD) due to neutron fission in 235U is an important design parameter. One of the more important AGR fuel testing requirements is to maintain the peak fuel compact temperature close to 1250°C throughout the proposed irradiation campaign of 550 effective full power days (EFPDs). Based on the MCWO-calculated FPD, a fixed gas gap size was designed to allow regulation of the fuel compact temperatures throughout the entire fuel irradiation campaign by filling the gap with a mixture of helium and neon gases. The chosen fixed gas gap can only regulate the peak fuel compact temperature in the desired range during the irradiation test if the ratio of the peak power density to the time-dependent low power density (P/T) at 550 EFPDs is less than 2.5. However, given the near constant neutron flux within the ATR driver core and the depletion of 235U in

  16. Automatic evaluation of density profiles with high temporal resolution (20μs) from FM broadband reflectometry on ASDEX-upgrade

    International Nuclear Information System (INIS)

    Varela, P.; Manso, M.E.

    1999-01-01

    The relevant information needed for the density profile evaluation from broadband reflectometry data is the group delay of the probing waves, due to the propagation and reflection at the cut-off layer, as a function of the probing frequency. In the presence of plasma fluctuations, it is difficult to detect the probing frequency curve due to the underlaying unperturbed density profile. The paper presents a novel spectral technique that is able to track the group delay curve under the presence of high levels of turbulence. The new method is based on the application of a best-path search algorithm to the energy time-frequency distribution obtained from the short-time Fourier transform of the reflected signal. This technique does not require narrow filtering or any fine adjustment of parameters, which makes it specially suitable for the automatic routine evaluation of density profiles. (A.L.B.)

  17. Lipid Profile

    Science.gov (United States)

    ... Known As Coronary Risk Panel Formal Name Lipid Profile This article was last reviewed on June 29, ... phospholipid molecules. The particles measured with a lipid profile are classified by their density into high-density ...

  18. Improving the Automatic Inversion of Digital ISIS-2 Ionogram Reflection Traces into Topside Vertical Electron-Density Profiles

    Science.gov (United States)

    Benson, R. F.; Truhlik, V.; Huang, X.; Wang, Y.; Bilitza, D.

    2011-01-01

    The topside-sounders on the four satellites of the International Satellites for Ionospheric Studies (ISIS) program were designed as analog systems. The resulting ionograms were displayed on 35-mm film for analysis by visual inspection. Each of these satellites, launched between 1962 and 1971, produced data for 10 to 20 years. A number of the original telemetry tapes from this large data set have been converted directly into digital records. Software, known as the TOPside Ionogram Scalar with True-height (TOPIST) algorithm has been produced that enables the automatic inversion of ISIS-2 ionogram reflection traces into topside vertical electron-density profiles Ne(h). More than million digital Alouette/ISIS topside ionograms have been produced and over 300,000 are from ISIS 2. Many of these ISIS-2 ionograms correspond to a passive mode of operation for the detection of natural radio emissions and thus do not contain ionospheric reflection traces. TOPIST, however, is not able to produce Ne(h) profiles from all of the ISIS-2 ionograms with reflection traces because some of them did not contain frequency information. This information was missing due to difficulties encountered during the analog-to-digital conversion process in the detection of the ionogram frame-sync pulse and/or the frequency markers. Of the many digital topside ionograms that TOPIST was able to process, over 200 were found where direct comparisons could be made with Ne(h) profiles that were produced by manual scaling in the early days of the ISIS program. While many of these comparisons indicated excellent agreement (<10% average difference over the entire profile) there were also many cases with large differences (more than a factor of two). Here we will report on two approaches to improve the automatic inversion process: (1) improve the quality of the digital ionogram database by remedying the missing frequency-information problem when possible, and (2) using the above-mentioned comparisons as

  19. Profiles

    International Nuclear Information System (INIS)

    2004-01-01

    Profiles is a synthetic overview of more than 100 national energy markets in the world, providing insightful facts and key energy statistics. A Profile is structured around 6 main items and completed by key statistics: Ministries, public agencies, energy policy are concerned; main companies in the oil, gas, electricity and coal sectors, status, shareholders; reserve, production, imports and exports, electricity and refining capacities; deregulation of prices, subsidies, taxes; consumption trends by sector, energy market shares; main energy projects, production and consumption prospects. Statistical Profiles are present in about 3 pages the main data and indicators on oil, gas, coal and electricity. (A.L.B.)

  20. Dislocation density and Burgers vector population in fiber-textured Ni thin films determined by high-resolution X-ray line profile analysis

    DEFF Research Database (Denmark)

    Csiszár, Gábor; Pantleon, Karen; Alimadadi, Hossein

    2012-01-01

    distribution are determined by high-resolution X-ray diffraction line profile analysis. The substructure parameters are correlated with the strength of the films by using the combined Taylor and Hall-Petch relations. The convolutional multiple whole profile method is used to obtain the substructure parameters......Nanocrystalline Ni thin films have been produced by direct current electrodeposition with different additives and current density in order to obtain 〈100〉, 〈111〉 and 〈211〉 major fiber textures. The dislocation density, the Burgers vector population and the coherently scattering domain size...

  1. Gemini NIFS survey of feeding and feedback processes in nearby active galaxies - II. The sample and surface mass density profiles

    Science.gov (United States)

    Riffel, R. A.; Storchi-Bergmann, T.; Riffel, R.; Davies, R.; Bianchin, M.; Diniz, M. R.; Schönell, A. J.; Burtscher, L.; Crenshaw, M.; Fischer, T. C.; Dahmer-Hahn, L. G.; Dametto, N. Z.; Rosario, D.

    2018-02-01

    We present and characterize a sample of 20 nearby Seyfert galaxies selected for having BAT 14-195 keV luminosities LX ≥ 1041.5 erg s-1, redshift z ≤ 0.015, being accessible for observations with the Gemini Near-Infrared Field Spectrograph (NIFS) and showing extended [O III]λ5007 emission. Our goal is to study Active Galactic Nucleus (AGN) feeding and feedback processes from near-infrared integral-field spectra, which include both ionized (H II) and hot molecular (H2) emission. This sample is complemented by other nine Seyfert galaxies previously observed with NIFS. We show that the host galaxy properties (absolute magnitudes MB, MH, central stellar velocity dispersion and axial ratio) show a similar distribution to those of the 69 BAT AGN. For the 20 galaxies already observed, we present surface mass density (Σ) profiles for H II and H2 in their inner ˜500 pc, showing that H II emission presents a steeper radial gradient than H2. This can be attributed to the different excitation mechanisms: ionization by AGN radiation for H II and heating by X-rays for H2. The mean surface mass densities are in the range (0.2 ≤ ΣH II ≤ 35.9) M⊙ pc-2, and (0.2 ≤ ΣH2 ≤ 13.9)× 10-3 M⊙ pc-2, while the ratios between the H II and H2 masses range between ˜200 and 8000. The sample presented here will be used in future papers to map AGN gas excitation and kinematics, providing a census of the mass inflow and outflow rates and power as well as their relation with the AGN luminosity.

  2. Fundamental length and relativistic length

    International Nuclear Information System (INIS)

    Strel'tsov, V.N.

    1988-01-01

    It si noted that the introduction of fundamental length contradicts the conventional representations concerning the contraction of the longitudinal size of fast-moving objects. The use of the concept of relativistic length and the following ''elongation formula'' permits one to solve this problem

  3. Hydrolysis Profiles of Formalin Fixed Paraffin-Embedded Tumors Based on IOD (Integrated Optical Density and Nuclear Texture Feature Measurements

    Directory of Open Access Journals (Sweden)

    Margareta Fležar

    1999-01-01

    Full Text Available The aim of the study was to determine optimal hydrolysis time for the Feulgen DNA staining of archival formalin fixed paraffin‐embedded surgical samples, prepared as single cell suspensions for image cytometric measurements. The nuclear texture features along with the IOD (integrated optical density of the tumor nuclei were analysed by an automated high resolution image cytometer as a function of duration of hydrolysis treatment (in 5 N HCl at room temperature. Tissue blocks of breast carcinoma, ovarian serous carcinoma, ovarian serous tumor of borderline malignancy and leiomyosarcoma were included in the study. IOD hydrolysis profiles showed plateau between 30 and 60 min in the breast carcinoma and leiomyosarcoma, and between 40 and 60 min in the ovarian serous carcinoma and ovarian serous tumor of borderline malignancy. Most of the nuclear texture features remained stable after 20 min of hydrolysis treatment. Our results indicate that the optimal hydrolysis time for IOD and for nuclear texture feature measurements, was between 40 and 60 min in the cell preparations from tissue blocks of three epithelial and one soft tissue tumor.

  4. Density functional study of pressure profile for hard-sphere fluids confined in a nano-cavity

    Directory of Open Access Journals (Sweden)

    Zongli Sun

    2014-02-01

    Full Text Available To gain a deeper understanding and to master the mechanical properties of classical fluids confined in nano-geometry, the pressure tensor applicable to confined fluids is derived by taking into account more correlation among the particles. First, based on classical statistical theory, the expression for the pressure tensor is calculated by expanding the stress tensor and considering further the correlation effect among the particles. Our numerical result is compared with that of molecular dynamics simulation and the agreement between them is quite good. Then, the dependence of the bulk density and the dimension of the cavity on the pressure profile is computed and studied. The curvature dependence of contact pressure and net pressure on the cavity wall is also studied. Finally, the solid–fluid interfacial tension is calculated and compared with Monte Carlo results. The results derived in this work indicate the importance and necessity of correlation among particles in the prediction of the mechanical properties of confined fluids.

  5. Flame Length

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — Flame length was modeled using FlamMap, an interagency fire behavior mapping and analysis program that computes potential fire behavior characteristics. The tool...

  6. Effect of Different Rearing Density on Survival Rate and Growth of Giant Gouramy Osphronemus gouramy Lac. Fry at Size of 2 cm in Length

    Directory of Open Access Journals (Sweden)

    I. Effendi

    2007-07-01

    Full Text Available Giant gouramy Osphronemus gouramy Lac is one of the fish for food that has high economic value, but its production is not  met with the market demand yet.  The effort is needed to be done in order to increase production of giant gouramy fry by an intensive hatchery system through high rearing density.  This study was performed to determine the effect of rearing density on survival rate and growth of fry.  Fry were reared in aquaria 60x29x33 cm filled with 35 liters water, and fed by Tubifex at satiation as much as  0.23-0.28 g/fry/day with feeding frequency  2 times a day.   Collected  data were survival rate, growth, feed consumption, feed efficiency, and water quality.  The result of study showed that survival rate and feed efficiency did not affected by rearing density, while growth and feed quantity were did.  Survival rate of fish was high; 90.14-99.52%.  Growth and feed consumption were decreased by increasing of  rearing density. Keywords: giant gouramy, Osphronemus gouramy, rearing density, growth   ABSTRAK Ikan gurame, Osphronemus gouramy Lac. merupakan salah satu jenis ikan konsumsi yang memiliki nilai ekonomi yang cukup tinggi, tetapi hasil produksinya masih belum dapat memenuhi permintaan pasar. Upaya perlu dilakukan untuk meningkatkan produksi benih ikan gurame dengan pembenihan secara intensif melalui peningkatan padat penebaran. Penelitian ini dilakukan untuk mengetahui pengaruh padat penebaran terhadap kelangsungan hidup dan pertumbuhan benih ikan gurami. Benih ikan gurami dipelihara pada akuarium berukuran 60×29×33 cm3 yang diisi air sebanyak 35 liter. Pakan berupa cacing sutera diberikan secara at satiation sebanyak 0,23 - 0,28 g/ekor/hari dengan frekuensi 2 kali/hari. Data yang diambil meliputi kelangsungan hidup, pertumbuhan, jumlah pakan yang dikonsumsi, efisiensi pakan dan kualitas air.  Hasil penelitian menunjukkan bahwa padat penebaran tidak mempengaruhi kelangsungan hidup dan efisiensi pakan, namun

  7. Monitoring of the mass density profile along the 0° geomagnetic longitude during magnetic storms with the use of ground magnetometers.

    Science.gov (United States)

    Romanova, N.; Stepanova, M. V.; Kozyreva, O. V.; Pilipenko, V.; Zesta, E.

    2015-12-01

    Ground magnetometers offer a very cheap and robust means of globally monitoring the magnetospheric mass density, by determining the ULF field line resonant frequency. ULF waves are almost always present in near-Earth environment and are generated by the solar wind interaction with the terrestrial magnetosphere. These waves from the magnetopause propagate through the magnetosphere. When they encounter a field line that resonates at the same frequency, coupling to the Alfven field line oscillations occurs and the resonance can be detected on the ground at that particular latitude. There are different methods for determining resonant frequencies from ground ULF waves. the density profiles along the 0° geomagnetic longitude were obtained using both the gradient and the amplitude-phase methods for the analysis of the magnetic field data from the magnetometer arrays: SAMBA (South American Meridional B-field Array), MAGDAS and American Antarctic bases (Palmer, WAIS-D). We compared the density profiles during quiet magnetic conditions and during strong magnetic storms (recovery phase). It is shown that in the recovery phase of strong magnetic storms (Dst <-150 nT) profile of the equatorial mass density varies greatly in comparison with the density distribution in quiet days.

  8. Optical mode engineering and high power density per facet length (>8.4 kW/cm) in tilted wave laser diodes

    Science.gov (United States)

    Ledentsov, N. N.; Shchukin, V. A.; Maximov, M. V.; Gordeev, N. Y.; Kaluzhniy, N. A.; Mintairov, S. A.; Payusov, A. S.; Shernyakov, Yu. M.

    2016-03-01

    Tilted Wave Lasers (TWLs) based on optically coupled thin active waveguide and thick passive waveguide offer an ultimate solution for thick-waveguide diode laser, preventing catastrophic optical mirror damage and thermal smile in laser bars, providing robust operation in external cavity modules thus enabling wavelength division multiplexing and further increase in brightness enabling direct applications of laser diodes in the mainstream material processing. We show that by proper engineering of the waveguide one can realize high performance laser diodes at different tilt angles of the vertical lobes. Two vertical lobes directed at various angles (namely, +/-27° or +/-9°) to the junction plane are experimentally realized by adjusting the compositions and the thicknesses of the active and the passive waveguide sections. The vertical far field of a TWL with the two +/-9° vertical beams allows above 95% of all the power to be concentrated within a vertical angle below 25°, the fact which is important for laser stack applications using conventional optical coupling schemes. The full width at half maximum of each beam of the value of 1.7° evidences diffraction- limited operation. The broad area (50 μm) TWL chips at the cavity length of 1.5 mm reveal a high differential efficiency ~90% and a current-source limited pulsed power >42W for as-cleaved TWL device. Thus the power per facet length in a laser bar in excess of 8.4 kW/cm can be realized. Further, an ultimate solution for the smallest tilt angle is that where the two vertical lobes merge forming a single lobe directed at the zero angle is proposed.

  9. The effect of ingestion of egg and low density lipoprotein (LDL oxidation on serum lipid profiles in hypercholesterolemic women

    Directory of Open Access Journals (Sweden)

    Taweesak Techakriengkrai1

    2012-04-01

    Full Text Available Egg is a major source of dietary cholesterol. The serum lipid response to egg shows marked individual variation, beingpartly genetically determined, and influence by ethnic groups and the overall diet response. In the present investigation, weinvestigated the effect of ingestion of egg and low density lipoprotein (LDL oxidation on serum lipid profile in hypercholesterolemicwomen. Forty hypercholesterolemic women volunteers on a cholesterol-lowering diet (CLD divided into 2 groups ina randomized controlled cross-over study of one egg per day (CLD + 1 egg for 4-week and three eggs per day (CLD + 3 eggsfor 4-week, separated by 4-week period egg-free. The body weight, blood pressure, serum lipid profiles and LDL oxidationwere measured at 4-week intervals. Cholesterol-lowering diet was applied throughout the study by a dietitian using a foodexchange program and 3-day dietary recall every 4 weeks. Compared to the values obtained at baseline, the mean serum totalcholesterol and LDL cholesterol of CLD + 3 eggs was not significantly different from baseline whereas of those of 4-week ofegg-free period and CLD + 1 egg were significantly decreased (238.3±2.9 mg/dL and 228.3±4.7 mg/dL compared to thebaseline (252.2±5.9 mg/dL as was LDL cholesterol (161.2±3.0 mg/dL and 155.7±4.8 mg/dL compared to the baseline (177.5±6.0 mg/dL (p<0.05. The study showed there were no significantly difference the body weight, blood pressure, HDL cholesterol,triglycerides or LDL oxidation during the study. However, serum total cholesterol and LDL cholesterol of 1 or 3 eggsper day after 4-week of egg consumption was not significantly higher than the egg-free period. The study suggests that inhypercholesterolemic women who are on cholesterol-lowering diet, consuming one or three eggs per day did not raise serumcholesterol or LDL cholesterol levels at 4 weeks or result in any change in LDL oxidation.

  10. Common Genetic Variation in the DKK1 Gene is Associated with Hip Axis Length but not with Bone Mineral Density and Bone Turnover Markers in Young Adult Men: Results from the Odense Androgen Study

    DEFF Research Database (Denmark)

    Piters, Elke; Balemans, Wendy; Nielsen, Torben Leo

    2010-01-01

    LRP5 was recently confirmed as an important susceptibility gene for osteoporosis. Our objective was to evaluate the effect of DKK1 polymorphisms on bone mineral density (BMD), hip geometry, and bone turnover. DKK1 is a secreted protein that binds to LRP5/6 receptors and inhibits canonical Wnt...... with hip axis length (HAL), independent of BMD and height. Moreover, the association seemed to be driven by the nonsedentary subgroup (P = 0.004). Haplotype analysis further confirmed the association of rs1569198 with HAL. Furthermore, we obtained indications for interaction between DKK1 and LRP5 genotypes...

  11. From slant column densities to trace gas profiles: Post processing data from the new MAX-DOAS network in Mexico City

    Science.gov (United States)

    Friedrich, M. M.; Stremme, W.; Rivera, C. I.; Arellano, E. J.; Grutter, M.

    2014-12-01

    The new MAX-DOAS network in Mexico City provides results of O4, HCHO and NO2 slant column densities (SCD). Here, we present a new numerical code developed to retrieve gas profiles of NO2 and HCHO using radiative transfer simulations. We present first results of such profiles from the MAX-DOAS station located at UNAM campus. The code works in two steps: First, the O4 slant column density information is used to retrieve an aerosol profile. As an a-priori aerosol profile, we use averaged ceilometer data measured at UNAM and scaled to the total optical depth provided by the Aeronet data base. In the second step, the retrieved aerosol profile information is used together with the trace gas (HCHO or NO2) SCDs to retrieve the trace gas profiles. The inversion is based on a gauss-newton iteration scheme and uses constrained least square fitting with either optimal estimation or Tihkonov regularization. For the latter, the regulation matrix is currently constructed from the discrete first derivative operator. The forward model uses the radiative transfer code VLIDORT. The inputs to VLIDORT are calculated using temperature and pressure information from daily radiosounde measurements and aerosol single scattering optical depths and asymmetry factors from the Aeronet data base for Mexico City. For the gas absorption cross sections we use the same values as were used for the SCD calculation from the recorded spectra using QDOAS. Besides demonstrating the functionality of the algorithm showing profile retrievals of simulated SCDs with added random noise, we present HCHO and NO2 profiles retrieved from SCDs calculated from the MAX-DOAS measurements at UNAM campus at selected days.

  12. A gravity study along a profile across the Sichuan Basin, the Qinling Mountains and the Ordos Basin (central China): Density, isostasy and dynamics

    Science.gov (United States)

    Zhang, Yongqian; Teng, Jiwen; Wang, Qianshen; Lü, Qingtian; Si, Xiang; Xu, Tao; Badal, José; Yan, Jiayong; Hao, Zhaobing

    2017-10-01

    In order to investigate the structure of the crust beneath the Middle Qinling Mountains (MQL) and neighboring areas in the North China Block and South China Block, a north-south gravity profile from Yuquan in the Sichuan Basin to Yulin in the Ordos Basin was conducted in 2011. The Bouguer gravity anomaly is determined from a high-quality gravity dataset collected between 31°N and 36°N of latitude, and varies between -200 and -110 mGal in the study region. Using accredited velocity density relationships, an initial crust-mantle density model is constructed for MQL and adjacent areas, which is later refined interactively to simulate the observed gravity anomaly. The present study reveals the features of the density and Bouguer gravity with respect to the tectonic units sampled by the profile. The lithosphere density model shows typical density values that depict a layered structure and allow differentiate the blocks that extend along the reference profile. The gravity field calculated by forward modeling from the final density distribution model correlates well with the measured gravity field within a standard deviation of 1.26 mGal. The density in the crystalline crust increases with depth from 2.65 g/cm3 up to the highest value of 2.95 g/cm3 near the bottom of the crust. The Conrad interface is identified as a density jump of about 0.05 g/cm3. The average density of the crust in MQL is clearly lower than the density in the formations on both sides. Starting from a combined Airy-Pratt isostatic compensation model, a partly compensated crust is found below MQL, suggesting future growth of the crust, unlike the Ordos and Sichuan basins that will remain stable. On the basis of the density and isostatic state of the crust and additional seismological research, such as the P-wave velocity model and Poisson's ratio, it is concluded that the lower crust delamination is a reasonable interpretation for the geophysical characteristics below the Qinling Orogen.

  13. Fundamental length

    International Nuclear Information System (INIS)

    Pradhan, T.

    1975-01-01

    The concept of fundamental length was first put forward by Heisenberg from purely dimensional reasons. From a study of the observed masses of the elementary particles known at that time, it is sumrised that this length should be of the order of magnitude 1 approximately 10 -13 cm. It was Heisenberg's belief that introduction of such a fundamental length would eliminate the divergence difficulties from relativistic quantum field theory by cutting off the high energy regions of the 'proper fields'. Since the divergence difficulties arise primarily due to infinite number of degrees of freedom, one simple remedy would be the introduction of a principle that limits these degrees of freedom by removing the effectiveness of the waves with a frequency exceeding a certain limit without destroying the relativistic invariance of the theory. The principle can be stated as follows: It is in principle impossible to invent an experiment of any kind that will permit a distintion between the positions of two particles at rest, the distance between which is below a certain limit. A more elegant way of introducing fundamental length into quantum theory is through commutation relations between two position operators. In quantum field theory such as quantum electrodynamics, it can be introduced through the commutation relation between two interpolating photon fields (vector potentials). (K.B.)

  14. Bond length and electric current oscillation of long linear carbon chains: Density functional theory, MpB model, and quantum spin transport studies

    International Nuclear Information System (INIS)

    Oeiras, R. Y.; Silva, E. Z. da

    2014-01-01

    Carbon linear atomic chains attached to graphene have experimentally been produced. Motivated by these results, we study the nature of the carbon bonds in these nanowires and how it affects their electrical properties. In the present study we investigate chains with different numbers of atoms and we observe that nanowires with odd number of atoms present a distinct behavior than the ones with even numbers. Using graphene nanoribbons as leads, we identify differences in the quantum transport of the chains with the consequence that even and odd numbered chains have low and high electrical conduction, respectively. We also noted a dependence of current with the wire size. We study this unexpected behavior using a combination of first principles calculations and simple models based on chemical bond theory. From our studies, the electrons of carbon nanowires present a quasi-free electron behavior and this explains qualitatively the high electrical conduction and the bond lengths with unexpected values for the case of odd nanowires. Our study also allows the understanding of the electric conduction dependence with the number of atoms and their parity in the chain. In the case of odd number chains a proposed π-bond (MpB) model describes unsaturated carbons that introduce a mobile π-bond that changes dramatically the structure and transport properties of these wires. Our results indicate that the nature of bonds plays the main role in the oscillation of quantum electrical conduction for chains with even and odd number of atoms and also that nanowires bonded to graphene nanoribbons behave as a quasi-free electron system, suggesting that this behavior is general and it could also remain if the chains are bonded to other materials

  15. A method for the retrieval of atomic oxygen density and temperature profiles from ground-based measurements of the O(+)(2D-2P) 7320 A twilight airglow

    Science.gov (United States)

    Fennelly, J. A.; Torr, D. G.; Richards, P. G.; Torr, M. R.; Sharp, W. E.

    1991-01-01

    This paper describes a technique for extracting thermospheric profiles of the atomic-oxygen density and temperature, using ground-based measurements of the O(+)(2D-2P) doublet at 7320 and 7330 A in the twilight airglow. In this method, a local photochemical model is used to calculate the 7320-A intensity; the method also utilizes an iterative inversion procedure based on the Levenberg-Marquardt method described by Press et al. (1986). The results demonstrate that, if the measurements are only limited by errors due to Poisson noise, the altitude profiles of neutral temperature and atomic oxygen concentration can be determined accurately using currently available spectrometers.

  16. rRNA:mRNA pairing alters the length and the symmetry of mRNA-protected fragments in ribosome profiling experiments

    OpenAIRE

    O?Connor, Patrick B. F.; Li, Gene-Wei; Weissman, Jonathan S.; Atkins, John F.; Baranov, Pavel V.

    2013-01-01

    Motivation: Ribosome profiling is a new technique that allows monitoring locations of translating ribosomes on mRNA at a whole transcriptome level. A recent ribosome profiling study demonstrated that internal Shine?Dalgarno (SD) sequences have a major global effect on translation rates in bacteria: ribosomes pause at SD sites in mRNA. Therefore, it is important to understand how SD sites effect mRNA movement through the ribosome and generation of ribosome footprints. Results: Here, we provide...

  17. Profiles of plasma parameters and density of negative hydrogen ions by laser detachment measurements in RF-driven ion sources; Profile der Plasmaparameter und Dichte negativer Wasserstoffionen mittels Laserdetachmentmessungen in HF-angeregten Ionenquellen

    Energy Technology Data Exchange (ETDEWEB)

    Christ-Koch, Sina

    2007-12-20

    This work shows the application of the Laserdetachment method for spatially resolved measurements of negative Hydrogen/Deuterium ion density. It was applied on a high power low pressure RF-driven ion source. The Laser detachment method is based on the measurement of electron currents on a positively biased Langmuir probe before and during/after a laser pulse. The density ratio of negative ions to electrons can be derived from the ratio of currents to the probe. The absolute density of negative ions can be obtained when the electron density is measured with the standard Langmuir probe setup. Measurements with the Langmuir probe additionally yield information about the floating and plasma potential, the electron temperature and the density of positive ions. The Laser detachment setup had to be adapted to the special conditions of the RF-driven source. In particular the existence of RF fields (1 MHz), high source potential (-20 kV), magnetic fields ({proportional_to} 7 mT) and caesium inside the source had to be considered. The density of negative ions could be identified in the range of n(H{sup -})=1.10{sup 17} 1/m{sup 3}, which is in the same order of magnitude as the electron density. Only the application of the Laser detachment method with the Langmuir probe measurements will yield spatially resolved plasma parameters and H- density profiles. The influence of diverse external parameters, such as pressure, RF-power, magnetic fields on the plasma parameters and their profiles were studied and explained. Hence, the measurements lead to a detailed understanding of the processes inside the source. (orig.)

  18. The large-scale correlations of multi-cell densities and profiles, implications for cosmic variance estimates

    OpenAIRE

    Codis, Sandrine; Bernardeau, Francis; Pichon, Christophe

    2016-01-01

    In order to quantify the error budget in the measured probability distribution functions of cell densities, the two-point statistics of cosmic densities in concentric spheres is investigated. Bias functions are introduced as the ratio of their two-point correlation function to the two-point correlation of the underlying dark matter distribution. They describe how cell densities are spatially correlated. They are computed here via the so-called large deviation principle in the quasi-linear reg...

  19. Evaluation of the methodologies used to generate random pavement profiles based on the power spectral density: An approach based on the International Roughness Index

    Directory of Open Access Journals (Sweden)

    Boris Jesús Goenaga

    2017-01-01

    Full Text Available The pavement roughness is the main variable that produces the vertical excitation in vehicles. Pavement profiles are the main determinant of (i discomfort perception on users and (ii dynamic loads generated at the tire-pavement interface, hence its evaluation constitutes an essential step on a Pavement Management System. The present document evaluates two specific techniques used to simulate pavement profiles; these are the shaping filter and the sinusoidal approach, both based on the Power Spectral Density. Pavement roughness was evaluated using the International Roughness Index (IRI, which represents the most used index to characterize longitudinal road profiles. Appropriate parameters were defined in the simulation process to obtain pavement profiles with specific ranges of IRI values using both simulation techniques. The results suggest that using a sinusoidal approach one can generate random profiles with IRI values that are representative of different road types, therefore, one could generate a profile for a paved or an unpaved road, representing all the proposed categories defined by ISO 8608 standard. On the other hand, to obtain similar results using the shaping filter approximation a modification in the simulation parameters is necessary. The new proposed values allow one to generate pavement profiles with high levels of roughness, covering a wider range of surface types. Finally, the results of the current investigation could be used to further improve our understanding on the effect of pavement roughness on tire pavement interaction. The evaluated methodologies could be used to generate random profiles with specific levels of roughness to assess its effect on dynamic loads generated at the tire-pavement interface and user’s perception of road condition.

  20. The role of concavo-convex walls of a nanopore on the density profile, adsorption, solvation force, and capillary condensation of confined fluids: A DFT study

    International Nuclear Information System (INIS)

    Helmi, Abbas; Keshavarzi, Ezat

    2014-01-01

    Highlights: • The effect of concavo-convex walls of nanopores on the density profile was studied. • For HS fluids the contact density at concave wall is greater than for convex wall. • For Yukawa fluid the contact density at concave wall can be less than convex wall. • Capillary condensation was observed for Yukawa fluids in the homocentric pores. - Abstract: We investigate the effects of concavo-convex walls of a nanopore on the structure and certain thermodynamic properties of confined fluids. Adsorption, solvation force, and capillary condensation in a nanopore formed between two homocentric spheres will be determined using the MFMT. For hard sphere fluids, contact density is greater at the concave wall than it is at the convex wall. In Yukawa fluids, for the thermodynamic state in which the energy effect is the dominant factor, contact density at a concave wall is less than that at a convex wall; this will be reversed for the thermodynamic state in which the entropy effect is the dominant factor. It is possible to find thermodynamic states in which contact densities at concave and convex walls become identical. The adsorption and solvation force of hard sphere fluid show an oscillatory behavior versus H. Capillary condensation is in certain cases observed for Yukawa fluids

  1. Retrieval of Stratospheric O3 and NO2 Density Profiles From a DOAS Analysis of UV-Visible Limb Scatter Measured by OSIRIS

    Science.gov (United States)

    Haley, C. S.; Sioris, C. E.; von Savigny, C.; McDade, I. C.; Griffioen, E.; McLinden, C. A.; Llewellyn, E. J.; ODIN Team

    2001-12-01

    Space-based atmospheric remote sounding measurements of minor species in the stratosphere using UV-visible radiances have traditionally been of two types: occultation measurements (POAM, SAGE) and nadir measurements (TOMS, GOME). These types of measurements are limited by either restricted spatial coverage (occultation) or poor vertical resolution (nadir). A new type of measurement, with the potential of providing both good spatial coverage and good vertical resolution, is limb scattered sunlight. This type of measurement has been used to recover O3 in the mesosphere and NO2 in the stratosphere from SME measurements and recently has been used to retrieve stratospheric ozone density profiles from SOLSE/LORE measurements. A number of new instruments are employing this method, including OSIRIS, onboard the recently launched Odin satellite, and SCIAMACHY, which will be launched on ENVISAT in late 2001. Though the measurements themselves are relatively straightforward to make, the process of retrieving minor species densities and other information from the radiances is complicated due to the viewing geometry. A method that has proved successful for analysing UV-visible measurements made with ground-based instruments and with satellite nadir-viewing instruments has been that of Differential Optical Absorption Spectroscopy (DOAS). With the DOAS method absorption features are used to recover slant column densities which are then converted to vertical column densities through calculated air mass factors. Here we present the application of the DOAS method to limb scattered sunlight. In this application, apparent column densities are calculated through an analysis of measured limb radiances in a similar fashion as the calculation of the slant column densities in other applications. The complication here is that there is no straightforward relationship between these apparent column densities and the vertical column density. We describe how these apparent column densities

  2. Scale-free gravitational collapse as the origin of ρ ˜ r-2 density profile - a possible role of turbulence in regulating gravitational collapse

    Science.gov (United States)

    Li, Guang-Xing

    2018-03-01

    Astrophysical systems, such as clumps that form star clusters share a density profile that is close to ρ ˜ r-2. We prove analytically this density profile is the result of the scale-free nature of the gravitational collapse. Therefore, it should emerge in many different situations as long as gravity is dominating the evolution for a period that is comparable or longer than the free-fall time, and this does not necessarily imply an isothermal model, as many have previously believed. To describe the collapse process, we construct a model called the turbulence-regulated gravitational collapse model, where turbulence is sustained by accretion and dissipates in roughly a crossing time. We demonstrate that a ρ ˜ r-2 profile emerges due to the scale-free nature the system. In this particular case, the rate of gravitational collapse is regulated by the rate at which turbulence dissipates the kinetic energy such that the infall speed can be 20-50% of the free-fall speed(which also depends on the interpretation of the crossing time based on simulations of driven turbulence). These predictions are consistent with existing observations, which suggests that these clumps are in the stage of turbulence-regulated gravitational collapse. Our analysis provides a unified description of gravitational collapse in different environments.

  3. Control of quasi-monoenergetic electron beams from laser-plasma accelerators by adjusting shock density profile

    Science.gov (United States)

    Tsai, Hai-En; Swanson, Kelly K.; Lehe, Remi; Barber, Sam K.; Isono, Fumika; Otero, Jorge G.; Liu, Xinyao; Mao, Hann-Shin; Steinke, Sven; Tilborg, Jeroen Van; Geddes, Cameron G. R.; Leemans, Wim

    2017-10-01

    High-level control of a laser-plasma accelerator (LPA) using a shock injector was demonstrated by systematically varying the shock injector profile, including the shock angle, up-ramp width and shock position. Particle-in-cell (PIC) simulation explored how variations in the shock profile impacted the injection process and confirmed results obtained through acceleration experiments. These results establish that, by adjusting shock position, up-ramp, and angle, beam energy, energy spread, and pointing can be controlled. As a result, e-beam were highly tunable from 25 to 300 MeV with Administration, Defense Nuclear Nonproliferation R&D (NA22).

  4. CLASH-VLT: The stellar mass function and stellar mass density profile of the z=0.44 cluster of galaxies MACS J1206.2-0847

    CERN Document Server

    Annunziatella, M; Mercurio, A.; Nonino, M.; Rosati, P.; Balestra, I.; Presotto, V.; Girardi, M.; Gobat, R.; Grillo, C.; Medezinski, E.; Kelson, D.; Postman, M.; Scodeggio, M.; Brescia, M.; Sartoris, B.; Demarco, R.; Fritz, A.; Koekemoer, A.; Lemze, D.; Lombardi, M.; Bradley, L.; Coe, D.; Donahue, M.; Regös, E.; Umetsu, K.; Vanzella, E.; Infante, L.; Kuchner, U.; Maier, C.; Verdugo, M.; Ziegler, B.

    2014-01-01

    Context. The study of the galaxy stellar mass function (SMF) in relation to the galaxy environment and the stellar mass density profile, rho(r), is a powerful tool to constrain models of galaxy evolution. Aims. We determine the SMF of the z=0.44 cluster of galaxies MACS J1206.2-0847 separately for passive and star-forming (SF) galaxies, in different regions of the cluster, from the center out to approximately 2 virial radii. We also determine rho(r) to compare it to the number density and total mass density profiles. Methods. We use the dataset from the CLASH-VLT survey. Stellar masses are obtained by SED fitting on 5-band photometric data obtained at the Subaru telescope. We identify 1363 cluster members down to a stellar mass of 10^9.5 Msolar. Results. The whole cluster SMF is well fitted by a double Schechter function. The SMFs of cluster SF and passive galaxies are statistically different. The SMF of the SF cluster galaxies does not depend on the environment. The SMF of the passive population has a signif...

  5. Evaluation of column length and particle size effect on the untargeted profiling of a phytochemical mixture by using UHPLC coupled to high-resolution mass spectrometry.

    Science.gov (United States)

    Zenezini Chiozzi, Riccardo; Capriotti, Anna Laura; Cavaliere, Chiara; Ferraris, Francesca; La Barbera, Giorgia; Piovesana, Susy; Laganà, Aldo

    2017-06-01

    Liquid chromatography coupled to high-resolution mass spectrometry is the technique of choice for the untargeted profiling of food matrices. Despite the high potential of high-resolution mass spectrometry, when dealing with complex mixtures, an efficient separation technique is also needed. The novel core-shell chromatographic columns packed with sub-2 μm sized particles are claimed to show very good resolution. However, the analytes retention can be significantly altered when working under ultra-high performance chromatographic conditions. In this work, an evaluation of four chromatographic systems, with either a single or two in-series Kinetex™ C 18 columns, either packed with 2.6 or 1.7 μm particles, is presented for the targeted analysis of a standard mixture and the untargeted analysis of a strawberry extract. An ultra-high performance chromatographic system coupled via an electrospray source to a hybrid quadrupole-Orbitrap mass spectrometer was used. From the extensive comparison, a surprising result was obtained, namely, that the system identifying the largest number of features was the one with two in-series connected columns with the larger particle size. The inconsistency among the theoretical assumptions and the applicative findings points out the importance of an extensive chromatographic evaluation for the comprehensive untargeted profiling of complex real samples. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Genetic relatedness among Campylobacter jejuni serotyped isolates of diverse origin as determined by numerical analysis of amplified fragment length polymorphism (AFLP) profiles

    DEFF Research Database (Denmark)

    Siemer, B.L.; Harrington, C.S.; Nielsen, E.M.

    2004-01-01

    health. The remaining 30 groups contained isolates from humans, chickens and associated food products, cattle, sheep, turkeys, ostriches and/or dogs. Strains assigned to serotypes 2, 6/7, 11 and 12 formed major clusters at the 77.6% S-level. Most other serotypes did not form homogeneous clusters......Aims: To use amplified fragment length polymorphism (AFLP) analysis to evaluate the genetic relatedness among 254 Campylobacter jejuni reference and field strains of diverse origin representing all defined 'Penner' serotypes for this species. Methods and Results: Field strains (n = 207) from human...... diarrhoea and diverse animal and environmental sources were collected mainly through a National surveillance programme in Denmark and serotyped by use of the established 'Penner' scheme. Genetic relationships among these isolates, and the archetypal serotype reference strains, were assessed by numerical...

  7. Tailoring high-density oligonucleotide arrays for transcript profiling of different Arabidopsis thaliana accessions using a sequence-based approach.

    Science.gov (United States)

    Boudichevskaia, Anastassia; Cao, Hieu Xuan; Schmidt, Renate

    2017-08-01

    Excluding polymorphic probes from GeneChip ® transcript profiling experiments via a sequence-based approach results in improved detection of differentially expressed genes in developing seeds of Arabidopsis thaliana accessions Col-0 and C24. GeneChip ® arrays represent a powerful tool for transcript profiling experiments. The ATH1 GeneChip ® has been designed based on the sequence of the Arabidopsis thaliana reference genome Col-0, hence the features on the array exactly match the sequences of Col-0 transcripts. In contrast, transcripts of other A. thaliana accessions or related species may show nucleotide differences and/or insertions/deletions when compared to the corresponding Col-0 transcripts, therefore, comparisons of transcript abundance involving different A. thaliana accessions or related species may be compromised for a certain number of transcripts. To tackle this limitation, a sequence-based strategy was developed. Only features on the array that were identical in sequence for the specimen to be compared were considered for transcript profiling. The impact of the proposed strategy was evaluated for transcript profiles that were established for developing seeds of A. thaliana accessions Col-0 and C24.

  8. Novel insights into structure-function mechanism and tissue-specific expression profiling of full-length dxr gene from Cymbopogon winterianus.

    Science.gov (United States)

    Devi, Kamalakshi; Dehury, Budheswar; Phukon, Munmi; Modi, Mahendra Kumar; Sen, Priyabrata

    2015-01-01

    The 1-deoxy-d-xylulose-5-phosphate reductoisomerase (DXR; EC1.1.1.267), an NADPH-dependent reductase, plays a pivotal role in the methylerythritol 4-phosphate pathway (MEP), in the conversion of 1-deoxy-d-xylulose-5-phosphate (DXP) into MEP. The sheath and leaf of citronella (Cymbopogon winterianus) accumulates large amount of terpenes and sesquiterpenes with proven medicinal value and economic uses. Thus, sequencing of full length dxr gene and its characterization seems to be a valuable resource in metabolic engineering to alter the flux of isoprenoid active ingredients in plants. In this study, full length DXR from citronella was characterized through in silico and tissue-specific expression studies to explain its structure-function mechanism, mode of cofactor recognition and differential expression. The modelled DXR has a three-domain architecture and its active site comprised of a cofactor (NADPH) binding pocket and the substrate-binding pocket. Molecular dynamics simulation studies indicated that DXR model retained most of its secondary structure during 10 ns simulation in aqueous solution. The modelled DXR superimposes well with its closest structural homolog but subtle variations in the charge distribution over the cofactor recognition site were noticed. Molecular docking study revealed critical residues aiding tight anchoring NADPH within the active pocket of DXR. Tissue-specific differential expression analysis using semi-quantitative RT-PCR and qRT-PCR in various tissues of citronella plant revealed distinct differential expression of DXR. To our knowledge, this is the first ever report on DXR from the important medicinal plant citronella and further characterization of this gene will open up better avenues for metabolic engineering of secondary metabolite pathway genes from medicinal plants in the near future.

  9. Novel insights into structure–function mechanism and tissue-specific expression profiling of full-length dxr gene from Cymbopogon winterianus

    Science.gov (United States)

    Devi, Kamalakshi; Dehury, Budheswar; Phukon, Munmi; Modi, Mahendra Kumar; Sen, Priyabrata

    2015-01-01

    The 1-deoxy-d-xylulose-5-phosphate reductoisomerase (DXR; EC1.1.1.267), an NADPH-dependent reductase, plays a pivotal role in the methylerythritol 4-phosphate pathway (MEP), in the conversion of 1-deoxy-d-xylulose-5-phosphate (DXP) into MEP. The sheath and leaf of citronella (Cymbopogon winterianus) accumulates large amount of terpenes and sesquiterpenes with proven medicinal value and economic uses. Thus, sequencing of full length dxr gene and its characterization seems to be a valuable resource in metabolic engineering to alter the flux of isoprenoid active ingredients in plants. In this study, full length DXR from citronella was characterized through in silico and tissue-specific expression studies to explain its structure–function mechanism, mode of cofactor recognition and differential expression. The modelled DXR has a three-domain architecture and its active site comprised of a cofactor (NADPH) binding pocket and the substrate-binding pocket. Molecular dynamics simulation studies indicated that DXR model retained most of its secondary structure during 10 ns simulation in aqueous solution. The modelled DXR superimposes well with its closest structural homolog but subtle variations in the charge distribution over the cofactor recognition site were noticed. Molecular docking study revealed critical residues aiding tight anchoring NADPH within the active pocket of DXR. Tissue-specific differential expression analysis using semi-quantitative RT-PCR and qRT-PCR in various tissues of citronella plant revealed distinct differential expression of DXR. To our knowledge, this is the first ever report on DXR from the important medicinal plant citronella and further characterization of this gene will open up better avenues for metabolic engineering of secondary metabolite pathway genes from medicinal plants in the near future. PMID:25941629

  10. Estimating vertical plant area density profile and growth parameters of a wheat canopy at different growth stages using three-dimensional portable lidar imaging

    Science.gov (United States)

    Hosoi, Fumiki; Omasa, Kenji

    Vertical plant area density profiles of wheat ( Triticum aestivum L.) canopy at different growth stages (tillering, stem elongation, flowering, and ripening stages) were estimated using high-resolution portable scanning lidar based on the voxel-based canopy profiling method. The canopy was scanned three-dimensionally by laser beams emitted from several measuring points surrounding the canopy. At the ripening stage, the central azimuth angle was inclined about 23 ∘ to the row direction to avoid obstruction of the beam into the lower canopy by the upper part. Plant area density profiles were estimated, with root mean square errors of 0.28-0.79 m 2 m -3 at each growth stage and of 0.45 m 2 m -3 across all growth stages. Plant area index was also estimated, with absolute errors of 4.7%-7.7% at each growth stage and of 6.1% across all growth stages. Based on lidar-derived plant area density, the area of each type of organ (stem, leaves, ears) per unit ground area was related to the actual dry weight of each organ type, and regression equations were obtained. The standard errors of the equations were 4.1 g m -2 for ears and 26.6 g m -2 for stems and leaves. Based on these equations, the estimated total dry weight was from 63.3 to 279.4 g m -2 for ears and from 35.8 to 375.3 g m -2 for stems and leaves across the growth stages. Based on the estimated dry weight at ripening and the ratio of carbon to dry weight in wheat plants, the carbon stocks were 76.3 g C m -2 for grain, 225.0 g C m -2 for aboveground residue, and 301.3 g C m -2 for all aboveground organs.

  11. Micrometry combined with profile mapping for the absolute measurement of Integrated Column Density (ICD) and for accurate X-ray mass attenuation coefficients using XERT

    Energy Technology Data Exchange (ETDEWEB)

    Islam, M. Tauhidul; Rae, Nicholas A.; Glover, Jack L.; Barnea, Zwi [School of Physics, University of Melbourne, Victoria 3010 (Australia); Chantler, Christopher T., E-mail: chantler@physics.unimelb.edu.a [School of Physics, University of Melbourne, Victoria 3010 (Australia)

    2010-07-21

    Absolute values of the column densities [{rho}t]{sub c} of four gold foils were measured using micrometry combined with the 2D X-ray attenuation profile. The absolute calibration of [{rho}t]{sub c} was made with a reference foil and the [{rho}t]{sub c} of other foils were determined following the thickness transfer method. By this method, we obtain absolute calibration to 0.1% or better which was not possible using only the X-ray map of a single foil over its central region.

  12. Possible influence of the Kuramoto length in a photo-catalytic water splitting reaction revealed by Poisson-Nernst-Planck equations involving ionization in a weak electrolyte

    Science.gov (United States)

    Suzuki, Yohichi; Seki, Kazuhiko

    2018-03-01

    We studied ion concentration profiles and the charge density gradient caused by electrode reactions in weak electrolytes by using the Poisson-Nernst-Planck equations without assuming charge neutrality. In weak electrolytes, only a small fraction of molecules is ionized in bulk. Ion concentration profiles depend on not only ion transport but also the ionization of molecules. We considered the ionization of molecules and ion association in weak electrolytes and obtained analytical expressions for ion densities, electrostatic potential profiles, and ion currents. We found the case that the total ion density gradient was given by the Kuramoto length which characterized the distance over which an ion diffuses before association. The charge density gradient is characterized by the Debye length for 1:1 weak electrolytes. We discuss the role of these length scales for efficient water splitting reactions using photo-electrocatalytic electrodes.

  13. Effects of atorvastatin and simvastatin on low-density lipoprotein subfraction profile, low-density lipoprotein oxidizability, and antibodies to oxidized low-density lipoprotein in relation to carotid intima media thickness in familial hypercholesterolemia.

    NARCIS (Netherlands)

    Tits, L.J.H. van; Smilde, T.J.; Wissen, S. van; Graaf, J. de; Kastelein, J.J.P.; Stalenhoef, A.F.H.

    2004-01-01

    BACKGROUND: Little is known about the effects of statins on the quality of circulating low-density lipoprotein (LDL) in relation to atherosclerosis progression. METHODS: In a double-blind, randomized trial of 325 patients with familial hypercholesterolemia (FH), we assessed the effects of high-dose

  14. Rayleigh-Brillouin scattering to determine one-dimensional temperature and number density profiles of a gas flow field

    Science.gov (United States)

    Lock, James A.; Seasholtz, Richard G.; John, W. T.

    1992-01-01

    Rayleigh-Brillouin spectra for heated nitrogen gas were measured by imaging the output of a Fabry-Perot interferometer onto a CCD array. The spectra were compared with the theoretical 6-moment model of Rayleigh-Brillouin scattering convolved with the Fabry-Perot instrument function. Estimates of the temperature and a dimensionless parameter proportional to the number density of the gas as functions of position in the laser beam were calculated by least-squares deviation fits between theory and experiment.

  15. Is Lipid Profile Associated with Bone Mineral Density and Bone Formation in Subjects with Spinal Cord Injury?

    Directory of Open Access Journals (Sweden)

    Hadis Sabour

    2014-01-01

    Full Text Available Purpose. The association between serum lipids and bone mineral density (BMD has been investigated previously but, up to now, these relationships have not yet been described in spinal cord injury (SCI. We tried to assess the correlation between serum triglyceride (TG, total cholesterol (TC, high-density lipoprotein (HDL, and low-density lipoprotein (LDL and BMD in male subjects with SCI. Methods. Dual-energy X-ray absorptiometry (DXA was used to assess BMD in femoral neck, trochanter, intertrochanteric zone, and lumbar vertebras. Blood samples were taken to measure serums lipids and bone biomarkers including osteocalcin, cross-linked type I collagen (CTX, and bone alkaline phosphatase (BALP. Partial correlation analysis was used to evaluate the relationships between mentioned measurements after adjustment for weight and age. Results. We found a positive correlation between HDL and femoral neck BMD (P: 0.004, r=0.33. HDL was negatively correlated with osteocalcin (P: 0.017, r=-0.31 which was not in consistency with its relationship with BMD. TC and LDL were not related to CTX, BALP and BMD. Conclusion. This study does not support a strong association between serum lipids and BMD in subjects with SCI. Moreover it seems that positive association between HDL and BMD is not mediated through increased bone formation.

  16. Determination of the solvent density profiles across mesopores of silica-C18 bonded phases in contact with acetonitrile/water mixtures: A semi-empirical approach.

    Science.gov (United States)

    Gritti, Fabrice

    2015-09-04

    The local volume fractions of water, acetonitrile, and C18-bonded chains across the 96Åmesopores of 5μm Symmetry particles were determined semi-empirically. The semi-empirical approach was based on previous molecular dynamics studies, which provided relevant mathematical expressions for the density profiles of C18 chains and water molecules, and on minor disturbance experiments, which measured the excess amount of acetonitrile adsorbed in the pores of Symmetry-C18 particles. The pore walls of the Symmetry-C18 material were in thermodynamic equilibrium with a series of binary mixtures of water and acetonitrile. The results show that C18 chains are mostly solvated by acetonitrile molecules, water is excluded from the C18-bonded layer, and acetonitrile concentrates across a 15-25Åthick interface region between the C18 layer and the bulk phase. These actual density profiles are expected to have a direct impact on the retention behaviour of charged, polar, and neutral analytes in RPLC. They also provide clues to predict the local mobility of analytes inside the pores and a sound physico-chemical description of the phenomenon of surface diffusion observed in RPLC. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. High-throughput immuno-profiling of mamba (Dendroaspis) venom toxin epitopes using high-density peptide microarrays

    DEFF Research Database (Denmark)

    Engmark, Mikael; Andersen, Mikael Rørdam; Laustsen, Andreas Hougaard

    2016-01-01

    Snakebite envenoming is a serious condition requiring medical attention and administration of antivenom. Current antivenoms are antibody preparations obtained from the plasma of animals immunised with whole venom(s) and contain antibodies against snake venom toxins, but also against other antigens....... In order to better understand the molecular interactions between antivenom antibodies and epitopes on snake venom toxins, a high-throughput immuno-profiling study on all manually curated toxins from Dendroaspis species and selected African Naja species was performed based on custom-made high...

  18. Intercomparison of density and temperature profiles obtained by lidar, ionizatoin gauges, falling spheres, datasondes and radiosondes during the DYANA campaign

    Science.gov (United States)

    Lubken, F.-J.; Hillert, W.; Lehmacher, G.; Von Zahn, U.; Bittner, M.; Offermann, D.; Schmidlin, F. J.; Hauchecorne, A.; Mourier, M.; Czechowsky, P.

    1994-01-01

    During the course of the DYnamics Adapted Network for the Atmosphere (DYANA) campaign in early 1990, various techniques to measure densities and temperatures from the ground up to the lower thermosphere were employed. Some of these measurements were performed near simultaneously (maximum allowed time difference: 1 h) and at the same location, and therefore offered the unique chance of intercomparison of different techniques. In this study, we will report on intercomparisons of data from ground-based instruments (Rayleigh- and sodium-lidar), balloon-borne methods (datasondes and radiosondes) and rocket-borne techniques (falling spheres and ionization gauges). The main result is that there is good agreement between the various measurements when considering the error bars. Only occasionally did we notice small but systematic differences (e.g. for the datasondes above 65 km). The most extensive intercomparison was possible between the Rayleigh lidar and the falling sphere technique, both employed in Biscarrosse (44 deg N, 1 deg W). Concerning densities, excellent agreement was found below 63 km: the mean of the deviations is less than 1% and the root mean square (RMS) is approximately 3%. Systematic differences of the order of 5% were noticed around 67 km and above 80 km. The former can be accounted for by an instrumental effect of the falling sphere (Ma = 1 transition; Ma = Mach number), whereas the latter is tentatively explained by the presence of Mie scatterers in the upper mesosphere. Concerning temperatures, the agreement is excellent between 35 and 65 km: the mean of the deviations is less than +/- 3 K and the variability is +/- 5 K. The two systematic density differences mentioned above also affect the temperatures: between 65 and 80 km, the Rayleigh lidar temperatures are systematically lower than the falling sphere values by approximately 5 K.

  19. Storage affects the phenolic profiles and antioxidant activities of cherries (Prunus avium L) on human low-density lipoproteins

    DEFF Research Database (Denmark)

    Goncalves, B.; Landbo, Anne-Katrine Regel; Let, Mette Bruni

    2004-01-01

    -performance liquid chromatography. Hydroxycinnamates dominated in all samples and represented 60-74% by weight of the phenols in the fresh and stored samples of the cvs Saco, Summit and Van, and 45% by weight of the phenols in the cv Burlat samples, which were richer in anthocyanins. The relative and total levels...... levels in the cvs Burlat and Saco. Phenolic cherry extracts inhibited low-density lipoprotein oxidation in vitro in a dose-dependent manner. Extracts of freshly harvested cherries exhibited significantly higher antioxidant activities than extracts of stored samples. The cv Summit samples had the highest...

  20. Similar Spectral Power Densities Within the Schumann Resonance and a Large Population of Quantitative Electroencephalographic Profiles: Supportive Evidence for Koenig and Pobachenko.

    Directory of Open Access Journals (Sweden)

    Kevin S Saroka

    Full Text Available In 1954 and 1960 Koenig and his colleagues described the remarkable similarities of spectral power density profiles and patterns between the earth-ionosphere resonance and human brain activity which also share magnitudes for both electric field (mV/m and magnetic field (pT components. In 2006 Pobachenko and colleagues reported real time coherence between variations in the Schumann and brain activity spectra within the 6-16 Hz band for a small sample. We examined the ratios of the average potential differences (~3 μV obtained by whole brain quantitative electroencephalography (QEEG between rostral-caudal and left-right (hemispheric comparisons of 238 measurements from 184 individuals over a 3.5 year period. Spectral densities for the rostral-caudal axis revealed a powerful peak at 10.25 Hz while the left-right peak was 1.95 Hz with beat-differences of ~7.5 to 8 Hz. When global cerebral measures were employed, the first (7-8 Hz, second (13-14 Hz and third (19-20 Hz harmonics of the Schumann resonances were discernable in averaged QEEG profiles in some but not all participants. The intensity of the endogenous Schumann resonance was related to the 'best-of-fitness' of the traditional 4-class microstate model. Additional measurements demonstrated real-time coherence for durations approximating microstates in spectral power density variations between Schumann frequencies measured in Sudbury, Canada and Cumiana, Italy with the QEEGs of local subjects. Our results confirm the measurements reported by earlier researchers that demonstrated unexpected similarities in the spectral patterns and strengths of electromagnetic fields generated by the human brain and the earth-ionospheric cavity.

  1. Similar Spectral Power Densities Within the Schumann Resonance and a Large Population of Quantitative Electroencephalographic Profiles: Supportive Evidence for Koenig and Pobachenko.

    Science.gov (United States)

    Saroka, Kevin S; Vares, David E; Persinger, Michael A

    2016-01-01

    In 1954 and 1960 Koenig and his colleagues described the remarkable similarities of spectral power density profiles and patterns between the earth-ionosphere resonance and human brain activity which also share magnitudes for both electric field (mV/m) and magnetic field (pT) components. In 2006 Pobachenko and colleagues reported real time coherence between variations in the Schumann and brain activity spectra within the 6-16 Hz band for a small sample. We examined the ratios of the average potential differences (~3 μV) obtained by whole brain quantitative electroencephalography (QEEG) between rostral-caudal and left-right (hemispheric) comparisons of 238 measurements from 184 individuals over a 3.5 year period. Spectral densities for the rostral-caudal axis revealed a powerful peak at 10.25 Hz while the left-right peak was 1.95 Hz with beat-differences of ~7.5 to 8 Hz. When global cerebral measures were employed, the first (7-8 Hz), second (13-14 Hz) and third (19-20 Hz) harmonics of the Schumann resonances were discernable in averaged QEEG profiles in some but not all participants. The intensity of the endogenous Schumann resonance was related to the 'best-of-fitness' of the traditional 4-class microstate model. Additional measurements demonstrated real-time coherence for durations approximating microstates in spectral power density variations between Schumann frequencies measured in Sudbury, Canada and Cumiana, Italy with the QEEGs of local subjects. Our results confirm the measurements reported by earlier researchers that demonstrated unexpected similarities in the spectral patterns and strengths of electromagnetic fields generated by the human brain and the earth-ionospheric cavity.

  2. Effects of exposure to moderate levels of ethanol during prenatal brain development on dendritic length, branching, and spine density in the nucleus accumbens and dorsal striatum of adult rats.

    Science.gov (United States)

    Rice, James P; Suggs, Lisa E; Lusk, Alexandra V; Parker, Matthew O; Candelaria-Cook, Felicha T; Akers, Katherine G; Savage, Daniel D; Hamilton, Derek A

    2012-09-01

    Reductions in measures of dendritic morphology in the agranular insular cortex have been identified as consequences of prenatal exposure to moderate levels of ethanol in the rat. Motivated by the strong connectivity between this region of frontal cortex and the striatum and a growing body of data linking specific components of the mesocortical/limbic system to effects of ethanol and ethanol self-administration, the current study investigated the effects of moderate fetal ethanol exposure on the dendritic morphology of medium spiny neurons (MSNs) in several regions of the striatum. Throughout gestation, pregnant rat dams either consumed a saccharin solution (control) or achieved average daily blood ethanol concentrations of 84 mg% via voluntary consumption of a 5% ethanol solution. The brains of adult male offspring were extracted and processed for Golgi-Cox staining. MSNs from the dorsomedial striatum, dorsolateral striatum and the nucleus accumbens core and shell were sampled for analysis. Relative to saccharin controls, robust reductions in dendritic length and branching, but not spine density, were observed in the shell of the nucleus accumbens in fetal-ethanol-exposed rats. No significant prenatal ethanol effects were found in the other regions of the striatum. These findings suggest that exposure to moderate levels of ethanol in utero can have profound effects on brain regions related to reward processing and provide possible clues relevant to understanding increased self-administration of drugs of abuse in animals exposed to ethanol during brain development. Copyright © 2012 Elsevier Inc. All rights reserved.

  3. A multichannel 118.8 μm-CH3OH laser interferometer for electron density profile measurements in LHD

    International Nuclear Information System (INIS)

    Kawahata, K.; Tanaka, K.; Tokuzawa, T.; Ito, Y.; Ejiri, A.; Okajima, S.

    2001-01-01

    A 13-channel far infrared laser interferometer has been developed and routinely operated for the measurements of the spatial and temporal behaviours of the electron density in the Large Helical Device (LHD). The optical configuration is of the Michelson interferometer type with a heterodyne detection system. The light source is a highly stable twin 118.8-μm CH 3 OH laser pumped by a cw CO 2 laser, which is developed in NIFS. All the optical components of the interferometer except laser sources are mounted on a massive stainless steel frame, which encircles the plasma vacuum vessel and is placed on three vibration-isolating mounts. The observed fringe shifts caused by the mechanical vibrations of the system is 1/100 fringes for the high frequency components of f > 1 Hz and 1/50 fringes for the low frequency components. The phase-shift measurement is made with an accuracy of 1/100 of a fringe, corresponding to a minimum measurable line-averaged density of 5.6 x 10 16 m -3 at the central chord. (author)

  4. Measurement of radial profiles of density ratio of helium to hydrogen ion using charge exchange spectroscopy with two-wavelength spectrometer.

    Science.gov (United States)

    Ida, K; Yoshinuma, M; Wieland, B; Goto, M; Nakamura, Y; Kobayashi, M; Murakami, I; Moon, C

    2015-12-01

    Radial profiles of density ratio of helium to hydrogen ions are measured using the charge exchange spectroscopy technique with the two-wavelength spectrometer system in the large helical device. The two-wavelength spectrometer system consists of a dichroic mirror box, a spectrometer with two grating and two camera lenses, and one CCD detector. The dichroic mirror box is used to divide the light of one fiber from the plasma to two fibers, one for HeII (λ = 468.6 nm) and the other for H(α) (λ = 656.3 nm), that are connected to the entrance slit of the spectrometer to eliminate the interference between the HeII and the H(α) spectra on the CCD. This system provides a simultaneous measurement of helium and hydrogen ion density ratio at 8 exact same locations (8 spatial channels) with a time resolution of >40 ms in the wide range of the density ratio of 0.05-5.

  5. CORRELATION OF H-MODE BARRIER WIDTH AND NEUTRAL PENTRATION LENGTH

    International Nuclear Information System (INIS)

    GROEBNER, R.J.; MAHDAVI, M.A.; LEONARD, A.W.; OSBORNE, T.H.; WOLF, N.S.; PORTER, G.D.; STANGEBY, P.C.; BROOKS, N.H.; COLCHIN, R.J.; HEIDBRINK, W.W.; LUCE, T.C.; MCKEE, G.R.; OWEN, L.W.; WANG, G.; WHYTE, D.G.

    2002-01-01

    OAK A271 CORRELATION OF H-MODE BARRIER WIDTH AND NEUTRAL PENTRATION LENGTH. Pedestal studies in DIII-D find a good correlation between the width of the region of steep gradient in the H-mode density and the neutral penetration length. These results are obtained by comparing experimental density profiles to the predictions of an analytic model for the profile, obtained from the particle continuity equations for electrons and deuterium atoms. In its range of validity (edge temperature between 40-500 eV), the analytic model quantitatively predicts the observed decrease of the width as the pedestal density increases, the observed strong increase of the gradient of the density as the pedestal density increases and the observation that L-mode and H-mode profiles with the same pedestal density have very similar shapes. The width of the density barrier, measured from the edge of the electron temperature barrier, is the lower limit for the observed width of the temperature barrier. These results support the hypothesis that particle fueling provides a dominant control for the size of the H-mode transport barrier

  6. Convective equilibrium and mixing-length theory for stellarator reactors

    Energy Technology Data Exchange (ETDEWEB)

    Ho, D.D.M.; Kulsrud, R.M.

    1985-09-01

    In high ..beta.. stellarator and tokamak reactors, the plasma pressure gradient in some regions of the plasma may exceed the critical pressure gradient set by ballooning instabilities. In these regions, convective cells break out to enhance the transport. As a result, the pressure gradient can rise only slightly above the critical gradient and the plasma is in another state of equilibrium - ''convective equilibrium'' - in these regions. Although the convective transport cannot be calculated precisely, it is shown that the density and temperature profiles in the convective region can still be estimated. A simple mixing-length theory, similar to that used for convection in stellar interiors, is introduced in this paper to provide a qualitative description of the convective cells and to show that the convective transport is highly efficient. A numerical example for obtaining the density and temperature profiles in a stellarator reactor is given.

  7. Convective equilibrium and mixing-length theory for stellarator reactors

    International Nuclear Information System (INIS)

    Ho, D.D.M.; Kulsrud, R.M.

    1985-09-01

    In high β stellarator and tokamak reactors, the plasma pressure gradient in some regions of the plasma may exceed the critical pressure gradient set by ballooning instabilities. In these regions, convective cells break out to enhance the transport. As a result, the pressure gradient can rise only slightly above the critical gradient and the plasma is in another state of equilibrium - ''convective equilibrium'' - in these regions. Although the convective transport cannot be calculated precisely, it is shown that the density and temperature profiles in the convective region can still be estimated. A simple mixing-length theory, similar to that used for convection in stellar interiors, is introduced in this paper to provide a qualitative description of the convective cells and to show that the convective transport is highly efficient. A numerical example for obtaining the density and temperature profiles in a stellarator reactor is given

  8. Development of an x-ray Talbot-Lau moire deflectometer for fast density profile measurements of dense plasmas generated by beam-target interactions

    Energy Technology Data Exchange (ETDEWEB)

    Clayton, Dan [National Security Technol., LLC, Los Alamos, NM (United States); Berninger, M; Meidinger, A; Stutman, Dan; Valdivia, Maria Pia

    2015-05-01

    For the first time an x-ray Talbot-Lau moire deflectometer is being developed that will use a flash tube source and fast detector for dynamic density gradient measurements. In Talbot-Lau moire deflectometry, an x-ray grating makes an image of itself on a second grating (the Talbot effect) to produce a moire pattern on a detector. The test object is placed between these gratings, with variations in index of refraction changing the pattern. A third grating in front of an incoherent x-ray source produces an array of coherent sources. With a 150 kV x-ray flash tube as the source, the gratings are placed in a glancing angle setup for performance at ~60 keV. The detector is a gated CCD with a fast scintillator for x-ray conversion. This diagnostic, designed for the Dual-Axis Radiographic Hydrodynamic Test facility (DARHT) at Los Alamos National Laboratory, measures the density profile of dense plasma plumes ejected from beam-target interactions. DARHT has two high-current, pulsed, inductive linear electron accelerators with bremsstrahlung targets at the end of each beam line to create 2-D radiographic images of hydrodynamic tests. One multi-pulse accelerator has up to four beam pulses striking the same target within 2 μs. Computer simulations that model target evolution and ejected material between pulses are used to design these targets for optimal radiographic performance; the x-ray deflectometer will directly measure density gradients in the ejected plumes and provide the first experimental constraints to these models. During the first year, currently underway, the diagnostic systems are being designed. In year two, the flash tube and fast detector will be deployed at DARHT for radiographic imaging while the deflectometer is built and tested on the bench with a continuous source. Finally, in year three, the fast deflectometer will be installed on DARHT and density measurements will be performed.

  9. On the relation between plasma and neutral gas profiles in a cold gas-blanket system

    International Nuclear Information System (INIS)

    Bures, M.

    1981-01-01

    A solution for the neutral density profile using the measured plasma density and temperature gradients is presented. The fluid model is used. It is found that the penetration length for neutrals is underestimated in the situation where the integrated profiles are used. The ionization rate need not be inferred in the present calculation, because the ionization of neutrals diffusing into the plasma is implicitly included in measured profiles. This calculation is advantageous in the low temperature range where the ionization rate is a strongly varying function of temperature. Finally the presented solution indicates that the temperature gradient plays the essential role in the determination of the neutral density profile. (Auth.)

  10. High-density PhyloChip profiling of stimulated aquifer microbial communities reveals a complex response to acetate amendment.

    Science.gov (United States)

    Handley, Kim M; Wrighton, Kelly C; Piceno, Yvette M; Andersen, Gary L; DeSantis, Todd Z; Williams, Kenneth H; Wilkins, Michael J; N'Guessan, A Lucie; Peacock, Aaron; Bargar, John; Long, Philip E; Banfield, Jillian F

    2012-07-01

    There is increasing interest in harnessing the functional capacities of indigenous microbial communities to transform and remediate a wide range of environmental contaminants. Information about which community members respond to stimulation can guide the interpretation and development of remediation approaches. To comprehensively determine community membership and abundance patterns among a suite of samples associated with uranium bioremediation experiments, we employed a high-density microarray (PhyloChip). Samples were unstimulated, naturally reducing, or collected during Fe(III) (early) and sulfate reduction (late biostimulation) from an acetate re-amended/amended aquifer in Rifle, Colorado, and from laboratory experiments using field-collected materials. Deep community sampling with PhyloChip identified hundreds-to-thousands of operational taxonomic units (OTUs) present during amendment, and revealed close similarity among highly enriched taxa from drill core and groundwater well-deployed column sediment. Overall, phylogenetic data suggested that stimulated community membership was most affected by a carryover effect between annual stimulation events. Nevertheless, OTUs within the Fe(III)- and sulfate-reducing lineages, Desulfuromonadales and Desulfobacterales, were repeatedly stimulated. Less consistent, co-enriched taxa represented additional lineages associated with Fe(III) and sulfate reduction (e.g. Desulfovibrionales; Syntrophobacterales; Peptococcaceae) and autotrophic sulfur oxidation (Sulfurovum; Campylobacterales). Data implies complex membership among highly stimulated taxa and, by inference, biogeochemical responses to acetate, a nonfermentable substrate. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  11. Mixed and monospecific stands of eucalyptus and black-wattle: I - fine root length density Plantios monoespecíficos e mistos de eucalipto e acácia-negra: I - densidade do comprimento de raízes finas

    Directory of Open Access Journals (Sweden)

    Márcio Viera

    2012-10-01

    Full Text Available Fine root length density (FRLD was evaluated in mixed and monospecific stands of Eucalyptus grandis x E. urophylla and Acacia mearnsii in Southern Brazil. FRLD (≤2,0mm at 8 and 18 months after planting in the treatments: 100E (100% of eucalyptus; 100A (100% of Acacia mearnsii; 50E:50A (50% of eucalyptus + 50% of Acacia mearnsii. The findings demonstrated that the FRLD at 8 months of age have the same distribution, in the two different species, in the distribution of the different soil layers, reaching the maximum projection of 125cm from the tree trunk. For the age of 18 months after planting, it was verified that the FRLD in the monospecific stand of Acacia mearnsii was higher than in the monoculture and mixed stand of Eucalyptus grandis x E. urophylla. Therefore, no interaction, neither positive nor negative, between the root systems of Eucalyptus grandis x E. urophylla and Acacia mearnsii during the 18 months after planting was found. The higher FRLD is found at the soil layers surface, next to the tree trunk and in the planting line, followed by the diagonal and planting rows. The initial growth in length of the root system of Acacia mearnsii is more dynamic with higher density than the eucalyptus, but without interfering directly in the global growth of fine roots in mixed stands.Avaliou-se a densidade do comprimento de raízes finas (DCRF de plantios monoespecíficos e misto de Eucalyptus grandis x E. urophylla e de Acacia mearnsii na região sul do Brasil. A DCRF (≤2,0mm foi determinada aos 8 e 18 meses após o plantio nos tratamentos: 100E (100% de eucalipto; 100A (100% de Acacia mearnsii; 50E:50A (50% de eucalipto + 50% de Acacia mearnsii. A DCRF aos oito meses de idade possui o mesmo comportamento para a ocupação das diferentes camadas do solo, atingindo uma projeção máxima de 125cm de distância em relação ao tronco da árvore. Já, aos 18 meses após o plantio, verificou-se que, no cultivo monoespecífico de Acacia

  12. [Number of teeth and hormonal profile of postmenopausal women with osteoporosis, osteopenia and normal bone mineral density--a preliminary study].

    Science.gov (United States)

    Stagraczyński, Maciej; Kulczyk, Tomasz; Leszczyński, Piotr; Męczekalski, Błażej

    2015-10-01

    Profound hypoestrogenism causes increased risk of osteoporosis and bone fracture in menopause. This period of women life is also characterized by decrease number of teeth and deterioration of oral cavity health. The aim of the study was to assess the number of teeth, hormonal profile (Follicle-stimualting hormone (FSH), estradiol (E2), testosterone (T) and dehydroepiandrosterone sulphate (DHEA-S) and the bone mineral density (BMD) of the lumbar part of the spine in postmenopausal women with osteoporosis, osteopenia and normal BMD. The next step of the study was to determine whether there was a correlation between vertebral mineral bone density, the hormonal profile and the number of teeth. A total number of 47 women was involved in the study. Based on the results of densitometry tests (DEXA) of vertebral column the subjects were divided into 3 groups: 10 with osteoporosis, 20 with osteopenia and 17 with normal BMD. All the subjects had undergone a hormonal assessment which included blood serum estimation for FSH, E2, DHEA-S and T levels. Also the total number of teeth present was recorded. Serum estradiol and testosterone levels in postmenopausal women were found to be positively correlated with the number of teeth present. A negative correlation was found between age and the number of maxillary teeth in postmenopausal women with osteopenia. There was no influence of serum FSH, estradiol, testosterone and DHEA-S levels on vertebral BMD loss in postmenopausal women. There was no correlation between teeth number and BMD of vertebral column. Serum levels of estradiol and testosterone in postmenopausal women positively correlate with teeth numbers. Age is the main risk factor for teeth loss in postmenopausal women. © 2015 MEDPRESS.

  13. Development of a heterodyne micro-wave reflectometer with ultra-fast sweeping. The study of the plasma turbulence influence on the measurements of electron density profile

    International Nuclear Information System (INIS)

    Moreau, Philippe

    1997-01-01

    The density profile of the fusion plasmas can be investigated by the reflectometry diagnostics. The measurement principle is based on the radar techniques which calculate the phase shift of a millimeter wave propagating into the plasma and reflected at a cut-off layer. However, this propagation is perturbed by the plasma turbulence. These phenomena affect the phase delay measurement by not well understood a process. In this work we have tried to find the mechanisms and origin of the turbulence which is responsible for the phase disturbance. We point out the role of collisionality and plasma radiation in controlling the instability and also, demonstrate that the phase delay of the probing wave is very sensitive to the plasma MHD phenomena and is less affected by the micro-turbulence. The second part of this work is the development and the use of a new heterodyne reflectometer. The principal characteristics are given. Its heterodyne detection allows the separation of phase and amplitude information from the detected signal and then to study their contribution to the mechanism of signal perturbation. The use of this reflectometer allows us to point out the following points: - a high dynamic availability, required by the large amplitude drops, often greater than 30 db; - fast sweep operation requirement to 'freeze' the plasma turbulence; - multiple reflection effects which modulate the amplitude and phase of the probing wave if they are not suppressed by filtering the detected signal; - very good localisation of the measurement (of the order of millimeter). The heterodyne reflectometer developed during this work offers several advantages of different distinct reflectometry techniques (fast sweep, absolute and differential phase measurements, heterodyne detection). It could be developed to work over higher frequency range so as to measure density profile over larger radial extension with very high performances. (author)

  14. Auroral E-region electron density height profile modificationby electric field driven vertical plasma transport:some evidence in EISCAT CP-1 data statistics

    Directory of Open Access Journals (Sweden)

    T. Bösinger

    2004-03-01

    Full Text Available A model developed several years ago by Huuskonen et al. (1984 predicted that vertical transport of ions in the nocturnal auroral E-region ionosphere can shift the electron density profiles in altitude during times of sufficiently large electric fields. If the vertical plasma transport effect was to operate over a sufficiently long enough time, then the real height of the E-region electron maximum should be shifted some km upwards (downwards in the eastward (westward auroral electrojet, respectively, when the electric field is strong, exceeding, say, 50 mV/m. Motivated by these predictions and the lack of any experimental verification so far, we made use of the large database of the European Incoherent Scatter (EISCAT radar to investigate if the anticipated vertical plasma transport is at work in the auroral E-region ionosphere and thus to test the Huuskonen et al. (1984 model. For this purpose a new type of EISCAT data display was developed which enabled us to order a large number of electron density height profiles, collected over 16 years of EISCAT operation, according to the electric field magnitude and direction as measured at the same time at the radar's magnetic field line in the F-region. Our analysis shows some signatures in tune with a vertical plasma transport in the auroral E-region of the type predicted by the Huuskonen et al. model. The evidence brought forward is, however, not unambiguous and requires more rigorous analysis.

    Key words. Ionosphere (auroral ionosphere; plasma convection; electric fields and currents

  15. High-density PhyloChip profiling of stimulated aquifer microbial communities reveals a complex response to acetate amendment

    Energy Technology Data Exchange (ETDEWEB)

    Handley, Kim M.; Wrighton, Kelly E.; Piceno, Y. M.; Anderson, Gary L.; DeSantis, Todd; Williams, Kenneth H.; Wilkins, Michael J.; N' Guessan, A. L.; Peacock, Aaron; Bargar, John R.; Long, Philip E.; Banfield, Jillian F.

    2012-06-13

    There is increasing interest in harnessing the functional diversity of indigenous microbial communities to transform and remediate a wide range of environmental contaminants. Understanding the response of communities to stimulation, including flanking taxa, presents important opportunities for optimizing remediation approaches. We used high-density PhyloChip microarray analysis to comprehensively determine community membership and abundance patterns amongst a suite of samples from U(VI) bioremediation experiments. Samples were unstimulated or collected during Fe(III) and sulfate reduction from an acetate-augmented aquifer in Rifle, Colorado, and from laboratory experiments using field-collected materials. Results showed the greatest diversity in abundant SRB lineages was present in naturally-reduced sediment. Desulfuromonadales and Desulfobacterales were consistently identified as the dominant Fe(III)- and sulfate-reducing bacteria (IRB and SRB) throughout acetate amendment experiments. Stimulated communities also exhibited a high degree of functional redundancy amongst enriched flanking members. Not surprisingly, competition for both sulfate and iron was evident amongst abundant taxa, but the distribution and abundance of these ancillary SRB (Peptococcaceae, Desulfovibrionales and Syntrophobacterales), and lineages containing IRB (excluding Desulfobacteraceae) was heterogeneous amongst sample types. Interesting, amongst the most abundant taxa, particularly during sulfate reduction, were Epsilonproteobacteria that perform microaerobic or nitrate-dependant sulfur oxidation, and a number of bacteria other than Geobacteraceae that may enzymatically reduce U(VI). Finally, in depth community probing with PhyloChip determined the efficacy of experimental approaches, notably revealing striking similarity amongst stimulated sediment (from drill cores and in-situ columns) and groundwater communities, and demonstrating that sediment-packed in-situ (down-well) columns served

  16. High-density marker profiling confirms ancestral genomes of Avena species and identifies D-genome chromosomes of hexaploid oat.

    Science.gov (United States)

    Yan, Honghai; Bekele, Wubishet A; Wight, Charlene P; Peng, Yuanying; Langdon, Tim; Latta, Robert G; Fu, Yong-Bi; Diederichsen, Axel; Howarth, Catherine J; Jellen, Eric N; Boyle, Brian; Wei, Yuming; Tinker, Nicholas A

    2016-11-01

    Genome analysis of 27 oat species identifies ancestral groups, delineates the D genome, and identifies ancestral origin of 21 mapped chromosomes in hexaploid oat. We investigated genomic relationships among 27 species of the genus Avena using high-density genetic markers revealed by genotyping-by-sequencing (GBS). Two methods of GBS analysis were used: one based on tag-level haplotypes that were previously mapped in cultivated hexaploid oat (A. sativa), and one intended to sample and enumerate tag-level haplotypes originating from all species under investigation. Qualitatively, both methods gave similar predictions regarding the clustering of species and shared ancestral genomes. Furthermore, results were consistent with previous phylogenies of the genus obtained with conventional approaches, supporting the robustness of whole genome GBS analysis. Evidence is presented to justify the final and definitive classification of the tetraploids A. insularis, A. maroccana (=A. magna), and A. murphyi as containing D-plus-C genomes, and not A-plus-C genomes, as is most often specified in past literature. Through electronic painting of the 21 chromosome representations in the hexaploid oat consensus map, we show how the relative frequency of matches between mapped hexaploid-derived haplotypes and AC (DC)-genome tetraploids vs. A- and C-genome diploids can accurately reveal the genome origin of all hexaploid chromosomes, including the approximate positions of inter-genome translocations. Evidence is provided that supports the continued classification of a diverged B genome in AB tetraploids, and it is confirmed that no extant A-genome diploids, including A. canariensis, are similar enough to the D genome of tetraploid and hexaploid oat to warrant consideration as a D-genome diploid.

  17. Reinvestigation on mixing length in an open channel turbulent flow

    Science.gov (United States)

    Kundu, Snehasis; Kumbhakar, Manotosh; Ghoshal, Koeli

    2018-02-01

    The present study proposes a model on vertical distribution of streamwise velocity in an open channel turbulent flow through a newly proposed mixing length, which is derived for both clear water and sediment-laden turbulent flows. The analysis is based on a theoretical consideration which explores the effect of density stratification on the streamwise velocity profile. The derivation of mixing length makes use of the diffusion equation where both the sediment diffusivity and momentum diffusivity are taken as a function of height from the channel bed. The damping factor present in the mixing length of sediment-fluid mixture contains velocity and concentration gradients. This factor is capable of describing the dip-phenomenon of velocity distribution. From the existing experimental data of velocity, the mixing length data are calculated. The pattern shows that mixing length increases from bed to the dip-position, having a larger value at dip-position and then decreases up to the water surface with a zero value thereat. The present model agrees well with these data sets and this behavior cannot be described by any other existing model. Finally, the proposed mixing length model is applied to find the velocity distribution in wide and narrow open channels. The derived velocity distribution is compared with laboratory channel data of velocity, and the comparison shows good agreement.

  18. Modeling the Lower Part of the Topside Ionospheric Vertical Electron Density Profile Over the European Region by Means of Swarm Satellites Data and IRI UP Method

    Science.gov (United States)

    Pignalberi, A.; Pezzopane, M.; Rizzi, R.

    2018-03-01

    An empirical method to model the lower part of the ionospheric topside region from the F2 layer peak height to about 500-600 km of altitude over the European region is proposed. The method is based on electron density values recorded from December 2013 to June 2016 by Swarm satellites and on foF2 and hmF2 values provided by IRI UP (International Reference Ionosphere UPdate), which is a method developed to update the IRI model relying on the assimilation of foF2 and M(3000)F2 data routinely recorded by a network of European ionosonde stations. Topside effective scale heights are calculated by fitting some definite analytical functions (α-Chapman, β-Chapman, Epstein, and exponential) through the values recorded by Swarm and the ones output by IRI UP, with the assumption that the effective scale height is constant in the altitude range considered. Calculated effective scale heights are then modeled as a function of foF2 and hmF2, in order to be operationally applicable to both ionosonde measurements and ionospheric models, like IRI. The method produces two-dimensional grids of the median effective scale height binned as a function of foF2 and hmF2, for each of the considered topside profiles. A statistical comparison with Constellation Observing System for Meteorology, Ionosphere, and Climate/FORMOsa SATellite-3 collected Radio Occultation profiles is carried out to assess the validity of the proposed method and to investigate which of the considered topside profiles is the best one. The α-Chapman topside function displays the best performance compared to the others and also when compared to the NeQuick topside option of IRI.

  19. Effect of the microenvironment and embryo density on developmental characteristics and gene expression profile of bovine preimplantative embryos cultured in vitro.

    Science.gov (United States)

    Hoelker, Michael; Rings, Franka; Lund, Qamaruddin; Ghanem, Nasser; Phatsara, Chirawath; Griese, Josef; Schellander, Karl; Tesfaye, Dawit

    2009-03-01

    The Well of the Well (WOW) system has been developed to culture embryos in small groups or to track the development of single embryos. In the present study, we aimed to examine the effects of the microenvironment provided by the WOW system and embryo density on developmental rates, embryo quality and preimplantative gene expression profile of the resulting embryos. Embryos cultured in a group of 16 reached the blastocyst stage at a significantly lower level than zygotes cultured in a group of 50 (22.2 vs 30.3%), whereas zygotes cultured in WOW were able to compensate against low embryo densities, reaching a blastocyst rate as high as embryos cultured in a group of 50 (31.3 vs 30.3%). Moreover, embryos derived from WOW culture did not differ in terms of differential cell counts and apoptotic cell index compared with controls. The gene expression analysis revealed 62 transcripts to be upregulated and 33 transcripts to be downregulated by WOW culture. Comparing the in vivo derived blastocysts with the blastocysts derived from WOW culture, and group culture, expression of ATP5A1, PLAC8 and KRT8 was more similar to the embryos derived from WOW culture, whereas expression of S100A10 and ZP3 genes was more similar to blastocysts cultured in a group. In conclusion, microenvironment as well as embryo density significantly affected developmental rates. While subsequent blastocysts did not differ in terms of differential cell counts and apoptotic cell index, significant differences were observed in terms of the relative abundance of transcripts in the resulting embryos.

  20. Characterization of gut microbiota profiles in coronary artery disease patients using data mining analysis of terminal restriction fragment length polymorphism: gut microbiota could be a diagnostic marker of coronary artery disease.

    Science.gov (United States)

    Emoto, Takuo; Yamashita, Tomoya; Kobayashi, Toshio; Sasaki, Naoto; Hirota, Yushi; Hayashi, Tomohiro; So, Anna; Kasahara, Kazuyuki; Yodoi, Keiko; Matsumoto, Takuya; Mizoguchi, Taiji; Ogawa, Wataru; Hirata, Ken-Ichi

    2017-01-01

    The association between atherosclerosis and gut microbiota has been attracting increased attention. We previously demonstrated a possible link between gut microbiota and coronary artery disease. Our aim of this study was to clarify the gut microbiota profiles in coronary artery disease patients using data mining analysis of terminal restriction fragment length polymorphism (T-RFLP). This study included 39 coronary artery disease (CAD) patients and 30 age- and sex- matched no-CAD controls (Ctrls) with coronary risk factors. Bacterial DNA was extracted from their fecal samples and analyzed by T-RFLP and data mining analysis using the classification and regression algorithm. Five additional CAD patients were newly recruited to confirm the reliability of this analysis. Data mining analysis could divide the composition of gut microbiota into 2 characteristic nodes. The CAD group was classified into 4 CAD pattern nodes (35/39 = 90 %), while the Ctrl group was classified into 3 Ctrl pattern nodes (28/30 = 93 %). Five additional CAD samples were applied to the same dividing model, which could validate the accuracy to predict the risk of CAD by data mining analysis. We could demonstrate that operational taxonomic unit 853 (OTU853), OTU657, and OTU990 were determined important both by the data mining method and by the usual statistical comparison. We classified the gut microbiota profiles in coronary artery disease patients using data mining analysis of T-RFLP data and demonstrated the possibility that gut microbiota is a diagnostic marker of suffering from CAD.

  1. Scattered light evidence for short density scale heights near critical density in laser-irradiated plasmas

    International Nuclear Information System (INIS)

    Phillion, D.W.; Lerche, R.A.; Rupert, V.C.; Haas, R.A.; Boyle, M.J.

    1976-01-01

    Experimental evidence is presented of a steepened electron density profile near critical density obtained from studying the time-integrated scattered light from targets illuminated by linearly polarized, 1.06 μ light. Both 10 μ thick disks and DT-filled glass microshells were irradiated by light focused by f/1 or f/2.5 lenses in one and two-beam experiments, respectively. From the dependence of the asymmetry of the scattered light about the beam axis upon the scattering angle, we infer scale lengths on the order of one micron. Scale lengths have also been deduced from measurements on the polarization state of the reflected light. Both analytic and numerical results are presented to show how the polarization state varies with the incidence angle and the scale length

  2. Scattered light evidence for short density scale heights near critical density in laser-irradiated plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Phillion, D.W.; Lerche, R.A.; Rupert, V.C.; Haas, R.A.; Boyle, M.J.

    1976-09-15

    Experimental evidence is presented of a steepened electron density profile near critical density obtained from studying the time-integrated scattered light from targets illuminated by linearly polarized, 1.06 ..mu.. light. Both 10 ..mu.. thick disks and DT-filled glass microshells were irradiated by light focused by f/1 or f/2.5 lenses in one and two-beam experiments, respectively. From the dependence of the asymmetry of the scattered light about the beam axis upon the scattering angle, we infer scale lengths on the order of one micron. Scale lengths have also been deduced from measurements on the polarization state of the reflected light. Both analytic and numerical results are presented to show how the polarization state varies with the incidence angle and the scale length.

  3. Density functional theory for polymeric systems in 2D.

    Science.gov (United States)

    Słyk, Edyta; Roth, Roland; Bryk, Paweł

    2016-06-22

    We propose density functional theory for polymeric fluids in two dimensions. The approach is based on Wertheim's first order thermodynamic perturbation theory (TPT) and closely follows density functional theory for polymers proposed by Yu and Wu (2002 J. Chem. Phys. 117 2368). As a simple application we evaluate the density profiles of tangent hard-disk polymers at hard walls. The theoretical predictions are compared against the results of the Monte Carlo simulations. We find that for short chain lengths the theoretical density profiles are in an excellent agreement with the Monte Carlo data. The agreement is less satisfactory for longer chains. The performance of the theory can be improved by recasting the approach using the self-consistent field theory formalism. When the self-avoiding chain statistics is used, the theory yields a marked improvement in the low density limit. Further improvements for long chains could be reached by going beyond the first order of TPT.

  4. High-Resolution Sedimentation Rates at IODP Sites U1424 and U1427 since the late Pliocene from spectral-analyzing GRA Bulk Density and RGB Color Profiles

    Science.gov (United States)

    Gorgas, Thomas; Irino, Tomohisa; Tada, Ryuji

    2016-04-01

    Sedimentation Rates (SRs) for IODP Sites U1424 (lat/lon coordinates: 40o11.40'N, 138o13.90'E; water depth: 2808 mbsl) and U1427 (lat/lon coordinates: 35o57.92'N, 134o26.06'E; water depth: 330 mbsl) were calculated by performing spectral analysis in the depth domain on both RGB color and Gamma-Ray-Attenuation (GRA) bulk density data. Inversion and integration of SRs versus depth from spectral analysis yielded detailed SR profiles in both time and depth domains. Our results show a greater variability in calculated SRs and differed from those established through coarse-scaled biostratigraphy and paleo-magnetic data. Our data analyses produces pulses of distinct high SRs for certain depth/age intervals at both sites, with time lags for such features possibly due to variable oceanographic conditions near-shore for Site U1427 versus those at Site U1424 further offshore. Both GRA and RGB profiles reveal a distinct periodicity in the waveband of Milankovitch cycles and other prominent periodicities in the 10-to-1ky period range. This observation suggests climate variabilities and trends in SRs responding to insolation patterns during the past 1 Myr at both sites and extending to 4.5 Myr for Site U1424. With only few identified eccentricity (100ky) cycle segments throughout the entire normalized spectral amplitude profile, our high-resolution Age-Depth model was tuned to obliquity (41ky) and precessional (19-23ky) cycles to achieving a strong fit with corresponding low-resolution models based on biostratigraphy, paleo-magnetic and, at least for Site U1424, augmenting volcanostratigraphy data. According to our Age-Depth models, relatively low SRs occur when evolutive amplitude spectra are dominated by periods in the range of obliquity and eccentricity. In contrast, significant SR peaks at both sites often occur when strong precessional amplitudes coexist with all other cycles. Lower SRs at Site U1424 have been interpreted to reflect a decrease in diatom flux and relative

  5. Vertical profiles of specific surface area, thermal conductivity and density of mid-latitude, Arctic and Antarctic snow: relationships between snow physics and climat

    Science.gov (United States)

    Domine, F.; Arnaud, L.; Bock, J.; Carmagnola, C.; Champollion, N.; Gallet, J.; Lesaffre, B.; Morin, S.; Picard, G.

    2011-12-01

    We have measured vertical profiles of specific surface area (SSA), thermal conductivity (TC) and density in snow from 12 different climatic regions featuring seasonal snowpacks of maritime, Alpine, taiga and tundra types, on Arctic sea ice, and from ice caps in Greenland and Antarctica. We attempt to relate snow physical properties to climatic variables including precipitation, temperature and its yearly variation, wind speed and its short scale temporal variations. As expected, temperature is a key variable that determines snow properties, mostly by determining the metamorphic regime (temperature gradient or equi-temperature) in conjunction with precipitation. However, wind speed and wind speed distribution also seem to have an at least as important role. For example high wind speeds determine the formation of windpacks of high SSA and high TC instead of depth hoar with lower values of these variables. The distribution of wind speed also strongly affects properties, as for example frequent moderate winds result in frequent snow remobilization, producing snow with higher SSA and lower TC than regions with the same average wind speeds, but with less frequent and more intense wind episodes. These strong effects of climate on snow properties imply that climate change will greatly modify snow properties, which in turn will affect climate, as for example changes in snow SSA modify albedo and changes in TC affect permafrost and the release of greenhouse gases from thawing permafrost. Some of these climate-snow feedbacks will be discussed.

  6. Detecting many-body-localization lengths with cold atoms

    Science.gov (United States)

    Guo, Xuefei; Li, Xiaopeng

    2018-03-01

    Considering ultracold atoms in optical lattices, we propose experimental protocols to study many-body-localization (MBL) length and criticality in quench dynamics. Through numerical simulations with exact diagonalization, we show that in the MBL phase the perturbed density profile following a local quench remains exponentially localized in postquench dynamics. The size of this density profile after long-time-dynamics defines a localization length, which tends to diverge at the MBL-to-ergodic transition as we increase the system size. The determined localization transition point agrees with previous exact diagonalization calculations using other diagnostics. Our numerical results provide evidence for violation of the Harris-Chayes bound for the MBL criticality. The critical exponent ν can be extracted from our proposed dynamical procedure, which can then be used directly in experiments to determine whether the Harris-Chayes-bound holds for the MBL transition. These proposed protocols to detect localization criticality are justified by benchmarking to the well-established results for the noninteracting three-dimensional Anderson localization.

  7. Analysis and Optimization of "Full-Length" Diodes

    Energy Technology Data Exchange (ETDEWEB)

    Schock, Alfred

    2012-01-19

    A method of analyzing the axial variation of the heat generation rate, temperature, voltage, current density and emitter heat flux in a thermionic converter is described. The method is particularly useful for the case of "long" diodes, each extending over the full length of the reactor core. For a given diode geometry and fuel distribution, the analysis combines a nuclear solution of the axial fission density profile with the iterative solution of four differential equations representing the thermal, electrical, and thermionic interactions within the diode. The digital computer program developed to solve these equations can also perform a design optimization with respect to lead resistance, load voltage, and emitter thickness, for a specified maximum emitter temperature. Typical results are presented, and the use of this analysis for predicting the diode operating characteristics is illustrated.

  8. Association between the biochemical profiles in blood and bone mineral density in Chinese Han population: findings from a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Chen HX

    2016-11-01

    Full Text Available Hong-Xia Chen,1,2,* Li-Bing Wu,3,* Zhong-Ji Meng1 1Institute of Biomedicine, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei Province, People’s Republic of China; 2Department of Environmental, Agricultural, & Occupational Health, College of Public Health, University of Nebraska Medical Center, Omaha, NE, USA; 3Department of Nuclear Medicine, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei Province, People’s Republic of China *These authors contributed equally to this work. Abstract: This study investigated the possible correlation between blood biochemical profiles and bone mineral density (BMD in the Chinese Han population. We conducted a cross-sectional analysis using participants randomly selected from the Health Screening Center of Taihe Hospital, Hubei University of Medicine, which included a total of 285 individuals, varied in ages from 31 years to 63 years. The height, weight, and body mass index (BMI of each subject were measured, as well as fasting blood glucose (FBG, triglycerides, total cholesterol, blood uric acid (UA, blood urea nitrogen, and blood creatinine. We evaluated BMD at the wrist (grams per centimeter square using a dual-energy X-ray absorptiometry scan. The mean ages of female and male groups were 45.32±8.24 years and 46.76±9.01 years, respectively. The mean age of the study population was 46.14±8.79 years, which is similar to the general population. The mean BMI values were 22.08±2.38 kg/m2 and 24.50±2.67 kg/m2 in the female and male population, respectively, representing a statistically significant difference (P<0.05. No significant differences in levels of FBG total cholesterol, or triglycerides were seen among the male and female population. Multiple linear regression analysis was performed using BMD as outcome variables and BMI, blood UA, FBG, total cholesterol, triglycerides, urea nitrogen, and blood creatinine as covariates, and the regression equation was established as Y=0

  9. Application of Thomson scattering at 1.06{mu}m as a diagnostic for spatial profile measurements of electron temperature and density on the TCV tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Franke, S. [Ecole Polytechnique Federale, Lausanne (Switzerland). Centre de Recherche en Physique des Plasma (CRPP)

    1997-04-01

    The variable configuration tokamak, TCV, in operation at CRPP since the end of 1991, is a particularly challenging machine with regard to the experimental system that must provide essential information regarding properties of confined plasmas with strongly shaped, non-circular cross-sections. The importance of the energy confinement issue in a machine designed specifically for the investigation of the effect of plasma shape on confinement and stability is self-evident, as is the necessity for a diagnostic capable of providing the profiles of electron temperature and density required for evaluation of this confinement. For TCV, a comprehensive Thomson Scattering (TS) diagnostic was the natural choice, specifically owing to the resulting spatially localized and time resolved measurement. The details of the system installed on TCV, together with the results obtained from the diagnostic comprise the subject matter of this thesis. A first version of the diagnostic was equipped with only ten observation volumes. In this case, adequate spatial resolution can only be maintained if measurements are limited to plasmas located in the upper half of the highly elongated TCV vacuum vessel. The system has recently been upgraded through the addition of a further fifteen observation volumes, together with major technical improvements in the scattered light detection system. This new version now permits TS observations in all TCV plasma configurations, including equilibria produced in the lower and upper halves of the vacuum vessel and the highly elongated plasmas now routinely created. Whilst a description of the new detection system along with some results obtained using the extended set of observation volumes are included, this thesis reports principally on the hardware details of and the interpretation of data from the original, ten observation volume system. (author) figs., tabs., 75 refs.

  10. Application of Thomson scattering at 1.06μm as a diagnostic for spatial profile measurements of electron temperature and density on the TCV tokamak

    International Nuclear Information System (INIS)

    Franke, S.

    1997-04-01

    The variable configuration tokamak, TCV, in operation at CRPP since the end of 1991, is a particularly challenging machine with regard to the experimental system that must provide essential information regarding properties of confined plasmas with strongly shaped, non-circular cross-sections. The importance of the energy confinement issue in a machine designed specifically for the investigation of the effect of plasma shape on confinement and stability is self-evident, as is the necessity for a diagnostic capable of providing the profiles of electron temperature and density required for evaluation of this confinement. For TCV, a comprehensive Thomson Scattering (TS) diagnostic was the natural choice, specifically owing to the resulting spatially localized and time resolved measurement. The details of the system installed on TCV, together with the results obtained from the diagnostic comprise the subject matter of this thesis. A first version of the diagnostic was equipped with only ten observation volumes. In this case, adequate spatial resolution can only be maintained if measurements are limited to plasmas located in the upper half of the highly elongated TCV vacuum vessel. The system has recently been upgraded through the addition of a further fifteen observation volumes, together with major technical improvements in the scattered light detection system. This new version now permits TS observations in all TCV plasma configurations, including equilibria produced in the lower and upper halves of the vacuum vessel and the highly elongated plasmas now routinely created. Whilst a description of the new detection system along with some results obtained using the extended set of observation volumes are included, this thesis reports principally on the hardware details of and the interpretation of data from the original, ten observation volume system. (author) figs., tabs., 75 refs

  11. Profiling and Racial Profiling: An Interactive Exercise

    Science.gov (United States)

    Semple, Philip

    2013-01-01

    Racial Profiling has been recognized as a serious problem that affects many segments of our society and is especially notable in law enforcement. Governments and police services have pronounced that racial profiling is not acceptable and will not be tolerated. They have gone to great lengths in trying to eradicate racial profiling through…

  12. A New well-constrained surface density profile of solids in Sun's protoplanetary disk: Implications for the formation of the inner Solar System

    Science.gov (United States)

    Aggarwal, Y. P.

    2016-12-01

    We present a highly correlated and significant relationship between a planet's rock mass of solids/heavy elements and its orbital radius found by non-linear regression analysis using existing data for all 8 planets except Mars. On its basis, we define the area A(r) of a planet's accretionary zone (AZ) and the surface density of solids σ(r) in Sun's disk that differs markedly from the commonly used minimum-mass solar nebula (MMSN) profile, and unlike MMSN is well constrained and does not produce contradictory results. A(r) ≈ π (1.59 r2 ̶ 0.16); and σ(r) = (5.95±0.1) (r - 6.4)- α where r is the heliocentric distance in astronomical units (AU), A(r) in AU², σ(r) in gm/cm², and α=0 for r ≤7.4AU, and α=1.39±0.04 for r ˃7.4AU. Using these relationships we determine the isolation masses of planetary embryos, define each planet's AZ, and analyze the size and spatial distribution of protoplanets within the AZ of terrestrial planets assuming typical protoplanet separations of 7-10 mutual Hill radii. The results: 1) show that Mars mass matches (±1%) with the isolation mass of its embryo and that its orbit at 1.52AU lies within its predicted AZ (1.47-1.54AU), establishing that Mars is a planetary embryo that formed in situ; 2) reveal that Mars failed to grow fully because there were not enough solids interior to Mars orbit to fully form all four terrestrial planets and because Jupiter accreted planetary embryos and planetesimals from the Mars-asteroid region, essentially depleting it; 3) imply that asteroids are remnant planetesimals that escaped accretion by Jupiter; 4) indicate that despite its small mass, Mercury is not a planetary embryo and that it probably completed its formation much earlier than Earth; and 5) suggest that Theia, the protoplanet thought to have impacted proto-Earth forming the Moon, originated near 1.45 AU with a mass and possibly composition similar to that of Mars. Notably, the results do not support the Grand Tack model or the

  13. Simulation of density measurements in plasma wakefields using photon acceleration

    Directory of Open Access Journals (Sweden)

    Muhammad Firmansyah Kasim

    2015-03-01

    Full Text Available One obstacle in plasma accelerator development is the limitation of techniques to diagnose and measure plasma wakefield parameters. In this paper, we present a novel concept for the density measurement of a plasma wakefield using photon acceleration, supported by extensive particle in cell simulations of a laser pulse that copropagates with a wakefield. The technique can provide the perturbed electron density profile in the laser’s reference frame, averaged over the propagation length, to be accurate within 10%. We discuss the limitations that affect the measurement: small frequency changes, photon trapping, laser displacement, stimulated Raman scattering, and laser beam divergence. By considering these processes, one can determine the optimal parameters of the laser pulse and its propagation length. This new technique allows a characterization of the density perturbation within a plasma wakefield accelerator.

  14. Simulation of density measurements in plasma wakefields using photo acceleration

    CERN Document Server

    Kasim, Muhammad Firmansyah; Ceurvorst, Luke; Sadler, James; Burrows, Philip N; Trines, Raoul; Holloway, James; Wing, Matthew; Bingham, Robert; Norreys, Peter

    2015-01-01

    One obstacle in plasma accelerator development is the limitation of techniques to diagnose and measure plasma wakefield parameters. In this paper, we present a novel concept for the density measurement of a plasma wakefield using photon acceleration, supported by extensive particle in cell simulations of a laser pulse that copropagates with a wakefield. The technique can provide the perturbed electron density profile in the laser’s reference frame, averaged over the propagation length, to be accurate within 10%. We discuss the limitations that affect the measurement: small frequency changes, photon trapping, laser displacement, stimulated Raman scattering, and laser beam divergence. By considering these processes, one can determine the optimal parameters of the laser pulse and its propagation length. This new technique allows a characterization of the density perturbation within a plasma wakefield accelerator.

  15. Two-dimensional density and density fluctuation diagnostic for the edge plasma in fusion devices

    Science.gov (United States)

    Zoletnik, S.; Petravich, G.; Bencze, A.; Berta, M.; Fiedler, S.; McCormick, K.; Schweinzer, J.

    2005-07-01

    A technique is described for the two-dimensional measurement of electron density profile and fluctuations in edge regions of magnetically confined fusion plasmas. The method is based on existing lithium beam beam emission spectroscopy technique, two-dimensional resolution is achieved by electrostatically scanning the beam. If scanning is performed faster than the lifetime of the turbulent structures in the plasma, the diagnostic is capable of measuring the structure of electron density fluctuations as well. The beam strength of currently available beams makes the detection of single fluctuation events impossible, but the full two-dimensional spatial structure of correlations can still be determined. The article describes the technique and fast beam deflection tests up to 250kHz. The capabilities of such a diagnostic for fluctuation measurement are explored by simulating measurement signals. Measurement of both the two-dimensional density profile, fluctuation correlation function and poloidal flow velocity are demonstrated at the Wendelstein 7-AS stellarator. The shape of the density profile, the radial and poloidal correlation lengths and the flow velocity are in agreement with expectations and previous Langmuir probe measurement.

  16. Telomere length analysis.

    Science.gov (United States)

    Canela, Andrés; Klatt, Peter; Blasco, María A

    2007-01-01

    Most somatic cells of long-lived species undergo telomere shortening throughout life. Critically short telomeres trigger loss of cell viability in tissues, which has been related to alteration of tissue function and loss of regenerative capabilities in aging and aging-related diseases. Hence, telomere length is an important biomarker for aging and can be used in the prognosis of aging diseases. These facts highlight the importance of developing methods for telomere length determination that can be employed to evaluate telomere length during the human aging process. Telomere length quantification methods have improved greatly in accuracy and sensitivity since the development of the conventional telomeric Southern blot. Here, we describe the different methodologies recently developed for telomere length quantification, as well as their potential applications for human aging studies.

  17. Density limits in Tokamaks

    International Nuclear Information System (INIS)

    Tendler, M.

    1984-06-01

    The energy loss from a tokamak plasma due to neutral hydrogen radiation and recycling is of great importance for the energy balance at the periphery. It is shown that the requirement for thermal equilibrium implies a constraint on the maximum attainable edge density. The relation to other density limits is discussed. The average plasma density is shown to be a strong function of the refuelling deposition profile. (author)

  18. Comparison of gemfibrozil versus simvastatin in familial combined hyperlipidemia and effects on apolipoprotein-B-containing lipoproteins, low-density lipoprotein subfraction profile, and low-density lipoprotein oxidizability

    NARCIS (Netherlands)

    Bredie, S. J.; de Bruin, T. W.; Demacker, P. N.; Kastelein, J. J.; Stalenhoef, A. F.

    1995-01-01

    We evaluated in a double-blind, placebo-controlled, randomized trial of 45 well-defined patients with familial combined hyperlipidemia, the effect of gemfibrozil (1,200 mg/day) or simvastatin (20 mg/day) on apolipoprotein-B (apo-B)-containing lipoproteins, low-density lipoprotein (LDL) subfraction

  19. Influence of shrub cover vegetal and slope length on soil bulk density; Influencia de la cubierta vegetal arbustiva y la longitud de la ladera sobre la densidad aparente del suelo

    Energy Technology Data Exchange (ETDEWEB)

    Bienes, R.; Jimenez, R.; Ruiz, M.; Garcia-Estringana, P.; Marques, M. J.

    2009-07-01

    In arid and semiarid environments of the Mediterranean climate, the shrub species play an important role in the revegetation of abandoned lands, which enables to control the soil losses, organic material and water. In this article are compared the results obtained under different revegetation in abandoned lands in the central area of Spain. In these revegetation has been used two native shrubs: A triplex halimus (Ah) and Retama sphaerocarpa (Rs), and were analyzed the influence of these revegetation in the contents of organic material of soil and apparent density in 5 years time after planting. As control, have been considered the pieces of ground with spontaneous vegetation abandoned in the same date that the shrubs revegetation. Atriplex halimus gives to the soil a covering capable to intercept a big amount of water drops absorbing a great amount part of the kinetic energy of the rain, while provides a microclimates as a result of be able to soften the wind, the temperature and the evaporation-transpiration, which makes it efficient to control the erosion and the desertification (Le Houerou, 2000). Retama sphaerocarpa was chosen because it is a native shrub very characteristic, and, due to its symbiosis with the Bradyrhizobium, enriches the soil in nitrogen, which is taken by the nitrophilous species enhancing the spontaneous vegetal covering. (Author) 9 refs.

  20. Fluid mixing in stratified gravity currents: the Prandtl mixing length.

    Science.gov (United States)

    Odier, P; Chen, J; Rivera, M K; Ecke, R E

    2009-04-03

    Shear-induced vertical mixing in a stratified flow is a key ingredient of thermohaline circulation. We experimentally determine the vertical flux of momentum and density of a forced gravity current using high-resolution velocity and density measurements. A constant eddy-viscosity model provides a poor description of the physics of mixing, but a Prandtl mixing length model relating momentum and density fluxes to mean velocity and density gradients works well. For the average gradient Richardson number Ri(g) approximately 0.08 and a Taylor Reynolds number Re(lambda) approximately 100, the mixing lengths are fairly constant, about the same magnitude, comparable to the turbulent shear length.

  1. Telomere length and depression

    DEFF Research Database (Denmark)

    Wium-Andersen, Marie Kim; Ørsted, David Dynnes; Rode, Line

    2017-01-01

    BACKGROUND: Depression has been cross-sectionally associated with short telomeres as a measure of biological age. However, the direction and nature of the association is currently unclear. AIMS: We examined whether short telomere length is associated with depression cross-sectionally as well...... as prospectively and genetically. METHOD: Telomere length and three polymorphisms, TERT, TERC and OBFC1, were measured in 67 306 individuals aged 20-100 years from the Danish general population and associated with register-based attendance at hospital for depression and purchase of antidepressant medication....... RESULTS: Attendance at hospital for depression was associated with short telomere length cross-sectionally, but not prospectively. Further, purchase of antidepressant medication was not associated with short telomere length cross-sectionally or prospectively. Mean follow-up was 7.6 years (range 0...

  2. Myofilament length dependent activation

    Energy Technology Data Exchange (ETDEWEB)

    de Tombe, Pieter P.; Mateja, Ryan D.; Tachampa, Kittipong; Mou, Younss Ait; Farman, Gerrie P.; Irving, Thomas C. (IIT); (Loyola)

    2010-05-25

    The Frank-Starling law of the heart describes the interrelationship between end-diastolic volume and cardiac ejection volume, a regulatory system that operates on a beat-to-beat basis. The main cellular mechanism that underlies this phenomenon is an increase in the responsiveness of cardiac myofilaments to activating Ca{sup 2+} ions at a longer sarcomere length, commonly referred to as myofilament length-dependent activation. This review focuses on what molecular mechanisms may underlie myofilament length dependency. Specifically, the roles of inter-filament spacing, thick and thin filament based regulation, as well as sarcomeric regulatory proteins are discussed. Although the 'Frank-Starling law of the heart' constitutes a fundamental cardiac property that has been appreciated for well over a century, it is still not known in muscle how the contractile apparatus transduces the information concerning sarcomere length to modulate ventricular pressure development.

  3. Upper Extremity Length Equalization

    OpenAIRE

    DeCoster, Thomas A.; Ritterbusch, John; Crawford, Mark

    1992-01-01

    Significant upper extremity length inequality is uncommon but can cause major functional problems. The ability to position and use the hand may be impaired by shortness of any of the long bones of the upper extremity. In many respects upper and lower extremity length problems are similar. They most commonly occur after injury to a growing bone and the treatment modalities utilized in the lower extremity may be applied to the upper extremity. These treatment options include epiphysiodesis, sho...

  4. Markers of lutein and zeaxanthin status in two age groups of men and women: dietary intake, serum concentrations, lipid profile and macular pigment optical density

    Science.gov (United States)

    2014-01-01

    Background & aims Lutein and zeaxanthin accumulate in retina (macular pigment). Their nutritional status can be assessed using dietary or biochemical markers and both have been associated with macular pigment optical density. We proposed to assess dietary and status markers of lutein and zeaxanthin in a group of healthy Spanish volunteers, considering the potential influence of age, gender and serum lipids to investigate the predictors of the macular pigment optical density. Methods Serum lutein and zeaxanthin concentrations, dietary intake and macular pigment optical density were determined in 108 healthy men and women (20–35 and 45–65 years), using high-performance liquid chromatography, 3-day food records and heterochromic flicker photometry, respectively. Mann–Whitney U-test, Spearman correlation coefficient and multivariate regression analysis were used for the statistical study. Results Serum concentrations and dietary intake of lutein plus zeaxanthin (p lutein (ρ = 0.452, p lutein + zeaxanthin (ρ = 0.431, p lutein and zeaxanthin were expressed in relation to serum lipids in older subjects (ρ = 0.262, p = 0.006). Multivariate regression analysis identified age and serum lutein as major predictors of macular pigment optical density (total sample), and a coefficient of determination of 29.7% for the model including lutein + zeaxathin/cholesterol + triglycerides, sex and fruit + vegetables in the older group. Conclusions The establishment of normal/reference ranges for serum lutein and zeaxanthin should consider age ranges and be expressed in relation to lipid concentrations, at least in subjects over 45 years, as this could influence macular pigment optical density. The macular pigment optical density showed age-specific correlations with lutein plus zeaxanthin expressed in relation to serum lipid concentrations as well as with the fruit and vegetable intake. PMID:24889185

  5. Relationships between seismic wave-Speed, density, and electrical conductivity beneath Australia from seismology, mineralogy, and laboratory-based conductivity profiles

    DEFF Research Database (Denmark)

    Khan, A.; Koch, S.; Shankland, T. J.

    2015-01-01

    We present maps of the three-dimensional density (ρ), electrical conductivity (σ), and shear-wave speed (VS) structure of the mantle beneath Australia and surrounding ocean in the depth range of 100–800 km. These maps derived from stochastic inversion of seismic surface-wave dispersion data, ther...

  6. Relativistic Length Agony Continued

    Science.gov (United States)

    Redzic, D. V.

    2014-06-01

    We made an attempt to remedy recent confusing treatments of some basic relativistic concepts and results. Following the argument presented in an earlier paper (Redzic 2008b), we discussed the misconceptions that are recurrent points in the literature devoted to teaching relativity such as: there is no change in the object in Special Relativity, illusory character of relativistic length contraction, stresses and strains induced by Lorentz contraction, and related issues. We gave several examples of the traps of everyday language that lurk in Special Relativity. To remove a possible conceptual and terminological muddle, we made a distinction between the relativistic length reduction and relativistic FitzGerald-Lorentz contraction, corresponding to a passive and an active aspect of length contraction, respectively; we pointed out that both aspects have fundamental dynamical contents. As an illustration of our considerations, we discussed briefly the Dewan-Beran-Bell spaceship paradox and the 'pole in a barn' paradox.

  7. Telomere Length and Mortality

    DEFF Research Database (Denmark)

    Kimura, Masayuki; Hjelmborg, Jacob V B; Gardner, Jeffrey P

    2008-01-01

    Leukocyte telomere length, representing the mean length of all telomeres in leukocytes, is ostensibly a bioindicator of human aging. The authors hypothesized that shorter telomeres might forecast imminent mortality in elderly people better than leukocyte telomere length. They performed mortality...... telomeres predicted the death of the first co-twin better than the mTRFL did (mTRFL: 0.56, 95% confidence interval (CI): 0.49, 0.63; mTRFL(50): 0.59, 95% CI: 0.52, 0.66; mTRFL(25): 0.59, 95% CI: 0.52, 0.66; MTRFL: 0.60, 95% CI: 0.53, 0.67). The telomere-mortality association was stronger in years 3-4 than...

  8. Quantitative analysis of Terminal Restriction Fragment Length Polymorphism (T-RFLP microbial community profiles: peak height data showed to be more reproducible than peak area Análise quantitativa de perfis de T-RFLP de comunidades microbianas: dados de altura de picos mostraram-se mais reprodutíveis do que os de área

    Directory of Open Access Journals (Sweden)

    Roberto A. Caffaro-Filho

    2007-12-01

    Full Text Available Terminal Restriction Fragment Length Polymorphism (T-RFLP is a culture-independent fingerprinting method for microbial community analysis. Profiles generated by an automated electrophoresis system can be analysed quantitatively using either peak height or peak area data. Statistical testing demontrated that peak height data showed to be more reproducible than peak area data.Terminal Restriction Fragment Length Polymorphism (T-RFLP é um método molecular, independente de cultivo, para análise de comunidades microbianas. Perfis gerados por um sistema automatizado de eletroforese podem ser analisados quantitativamente usando dados de altura ou área dos picos. Os dados de altura mostraram-se mais reprodutíveis do que os de área.

  9. Kink and Sausage Modes in Nonuniform Magnetic Slabs with Continuous Transverse Density Distributions

    Science.gov (United States)

    Yu, Hui; Li, Bo; Chen, Shao-Xia; Guo, Ming-Zhe

    2015-11-01

    We examine the influence of a continuous density structuring transverse to coronal slabs on the dispersive properties of fundamental standing kink and sausage modes supported therein. We derive generic dispersion relations (DRs) governing linear fast waves in pressureless straight slabs with general transverse density distributions, and focus on cases where the density inhomogeneity takes place in a layer of arbitrary width and in arbitrary form. The physical relevance of the solutions to the DRs is demonstrated by the corresponding time-dependent computations. For all profiles examined, the lowest order kink modes are trapped regardless of longitudinal wavenumber k. A continuous density distribution introduces a difference to their periods of ≲13% when k is the observed range relative to the case where the density profile takes a step function form. Sausage modes and other branches of kink modes are leaky at small k, and their periods and damping times are heavily influenced by how the transverse density profile is prescribed, in particular the length scale. These modes have sufficiently high quality to be observable only for physical parameters representative of flare loops. We conclude that while the simpler DR pertinent to a step function profile can be used for the lowest order kink modes, the detailed information on the transverse density structuring needs to be incorporated into studies of sausage modes and higher order kink modes.

  10. KINK AND SAUSAGE MODES IN NONUNIFORM MAGNETIC SLABS WITH CONTINUOUS TRANSVERSE DENSITY DISTRIBUTIONS

    International Nuclear Information System (INIS)

    Yu, Hui; Li, Bo; Chen, Shao-Xia; Guo, Ming-Zhe

    2015-01-01

    We examine the influence of a continuous density structuring transverse to coronal slabs on the dispersive properties of fundamental standing kink and sausage modes supported therein. We derive generic dispersion relations (DRs) governing linear fast waves in pressureless straight slabs with general transverse density distributions, and focus on cases where the density inhomogeneity takes place in a layer of arbitrary width and in arbitrary form. The physical relevance of the solutions to the DRs is demonstrated by the corresponding time-dependent computations. For all profiles examined, the lowest order kink modes are trapped regardless of longitudinal wavenumber k. A continuous density distribution introduces a difference to their periods of ≲13% when k is the observed range relative to the case where the density profile takes a step function form. Sausage modes and other branches of kink modes are leaky at small k, and their periods and damping times are heavily influenced by how the transverse density profile is prescribed, in particular the length scale. These modes have sufficiently high quality to be observable only for physical parameters representative of flare loops. We conclude that while the simpler DR pertinent to a step function profile can be used for the lowest order kink modes, the detailed information on the transverse density structuring needs to be incorporated into studies of sausage modes and higher order kink modes

  11. Full Length Research Article

    African Journals Online (AJOL)

    Administrator

    Out of the 320 male sheep examined, 87(27.2%) were infected, while 9(19.1%) of the 47 females examined were infected (Table 2). Infection varied from one abattoir to another. Age related distribution of P. cervi is shown in Table 3. Out of 356 adult sheep (>2yrs) examined, 35. Full Length Research Article. 12 ...

  12. Mixing lengths scaling in a gravity flow

    Energy Technology Data Exchange (ETDEWEB)

    Ecke, Robert E [Los Alamos National Laboratory; Rivera, Micheal [Los Alamos National Laboratory; Chen, Jun [Los Alamos National Laboratory; Ecke, Robert E [Los Alamos National Laboratory

    2009-01-01

    We present an experimental study of the mixing processes in a gravity current. The turbulent transport of momentum and buoyancy can be described in a very direct and compact form by a Prandtl mixing length model [1]: the turbulent vertical fluxes of momentum and buoyancy are found to scale quadraticatly with the vertical mean gradients of velocity and density. The scaling coefficient is the square of the mixing length, approximately constant over the mixing zone of the stratified shear layer. We show in this paper how, in different flow configurations, this length can be related to the shear length of the flow {radical}({var_epsilon}/{partial_derivative}{sub z}u{sup 3}).

  13. Does the nutrition profile of vitamins, fatty acids and microelements counteract the negative impact from organohalogen pollutants on bone mineral density in Greenland sledge dogs (Canis familiaris)?

    DEFF Research Database (Denmark)

    Sonne, Christian; Rigét, Frank F; Beck Jensen, Jens-Erik

    2008-01-01

    There is a great need for understanding the impact from dietary OHCs (organohalogen compounds) on bone mineral composition - and thereby osteoporosis - in especially arctic wildlife such as polar bears (Ursus maritimus) as well as humans. For that purpose, we measured BMD (bone mineral density...... an impact on BMD using the present time frame and OHC concentrations (threshold levels not reached), or the difference in food composition (mainly vitamins and n3 fatty acids) conceal the potential OHC impact on BMD. Such information is important when evaluating the positive and negative health consequences...

  14. Does the nutrition profile of vitamins, fatty acids and microelements counteract the negative impact from organohalogen pollutants on bone mineral density in Greenland sledge dogs (Canis familiaris)?

    DEFF Research Database (Denmark)

    Sonne, Christian; Riget, Frank F.; Jensen, Jens-Erik Beck

    2008-01-01

    There is a great need for understanding the impact from dietary OHCs (organohalogen compounds) on bone mineral composition - and thereby osteoporosis - in especially arctic wildlife such as polar bears (Ursus maritimus) as well as humans. For that purpose, we measured BMD (bone mineral density...... using the present time frame and OHC concentrations (threshold levels not reached), or the difference in food composition (mainly vitamins and n3 fatty acids) conceal the potential OHC impact on BMD. Such information is important when evaluating the positive and negative health consequences from eating...

  15. Gap length distributions by PEPR

    International Nuclear Information System (INIS)

    Warszawer, T.N.

    1980-01-01

    Conditions guaranteeing exponential gap length distributions are formulated and discussed. Exponential gap length distributions of bubble chamber tracks first obtained on a CRT device are presented. Distributions of resulting average gap lengths and their velocity dependence are discussed. (orig.)

  16. Length of excitable knots

    Science.gov (United States)

    Maucher, Fabian; Sutcliffe, Paul

    2017-07-01

    In this paper, we present extensive numerical simulations of an excitable medium to study the long-term dynamics of knotted vortex strings for all torus knots up to crossing number 11. We demonstrate that FitzHugh-Nagumo evolution preserves the knot topology for all the examples presented, thereby providing a field theory approach to the study of knots. Furthermore, the evolution yields a well-defined minimal length for each knot that is comparable to the ropelength of ideal knots. We highlight the role of the medium boundary in stabilizing the length of the knot and discuss the implications beyond torus knots. We also show that there is not a unique attractor within a given knot topology.

  17. Pion nucleus scattering lengths

    International Nuclear Information System (INIS)

    Huang, W.T.; Levinson, C.A.; Banerjee, M.K.

    1971-09-01

    Soft pion theory and the Fubini-Furlan mass dispersion relations have been used to analyze the pion nucleon scattering lengths and obtain a value for the sigma commutator term. With this value and using the same principles, scattering lengths have been predicted for nuclei with mass number ranging from 6 to 23. Agreement with experiment is very good. For those who believe in the Gell-Mann-Levy sigma model, the evaluation of the commutator yields the value 0.26(m/sub σ//m/sub π/) 2 for the sigma nucleon coupling constant. The large dispersive corrections for the isosymmetric case implies that the basic idea behind many of the soft pion calculations, namely, slow variation of matrix elements from the soft pion limit to the physical pion mass, is not correct. 11 refs., 1 fig., 3 tabs

  18. Negative Ion Density Fronts

    International Nuclear Information System (INIS)

    Igor Kaganovich

    2000-01-01

    Negative ions tend to stratify in electronegative plasmas with hot electrons (electron temperature Te much larger than ion temperature Ti, Te > Ti ). The boundary separating a plasma containing negative ions, and a plasma, without negative ions, is usually thin, so that the negative ion density falls rapidly to zero-forming a negative ion density front. We review theoretical, experimental and numerical results giving the spatio-temporal evolution of negative ion density fronts during plasma ignition, the steady state, and extinction (afterglow). During plasma ignition, negative ion fronts are the result of the break of smooth plasma density profiles during nonlinear convection. In a steady-state plasma, the fronts are boundary layers with steepening of ion density profiles due to nonlinear convection also. But during plasma extinction, the ion fronts are of a completely different nature. Negative ions diffuse freely in the plasma core (no convection), whereas the negative ion front propagates towards the chamber walls with a nearly constant velocity. The concept of fronts turns out to be very effective in analysis of plasma density profile evolution in strongly non-isothermal plasmas

  19. Length-weight and length-length relationships of freshwater wild ...

    African Journals Online (AJOL)

    Length-weight and length-length relationships of freshwater wild catfish Mystus bleekeri from Nala Daik, Sialkot, Pakistan. ... Linear regression analysis was used, first to compute the degree of relationship between length and weight and then among total (TL), standard (SL) and fork lengths (FL). LWR exhibited a highly ...

  20. Relativistic length agony continued

    Directory of Open Access Journals (Sweden)

    Redžić D.V.

    2014-01-01

    Full Text Available We made an attempt to remedy recent confusing treatments of some basic relativistic concepts and results. Following the argument presented in an earlier paper (Redžić 2008b, we discussed the misconceptions that are recurrent points in the literature devoted to teaching relativity such as: there is no change in the object in Special Relativity, illusory character of relativistic length contraction, stresses and strains induced by Lorentz contraction, and related issues. We gave several examples of the traps of everyday language that lurk in Special Relativity. To remove a possible conceptual and terminological muddle, we made a distinction between the relativistic length reduction and relativistic FitzGerald-Lorentz contraction, corresponding to a passive and an active aspect of length contraction, respectively; we pointed out that both aspects have fundamental dynamical contents. As an illustration of our considerations, we discussed briefly the Dewan-Beran-Bell spaceship paradox and the ‘pole in a barn’ paradox. [Projekat Ministarstva nauke Republike Srbije, br. 171028

  1. HOW TO MAKE AN ULTRA-FAINT DWARF SPHEROIDAL GALAXY: TIDAL STIRRING OF DISKY DWARFS WITH SHALLOW DARK MATTER DENSITY PROFILES

    International Nuclear Information System (INIS)

    Łokas, Ewa L.; Kazantzidis, Stelios; Mayer, Lucio

    2012-01-01

    In recent years the Sloan Digital Sky Survey has unraveled a new population of ultra-faint dwarf galaxies (UFDs) whose origin remains a puzzle in the vicinity of the Milky Way (MW). Using a suite of collisionless N-body simulations, we investigate the formation of UFDs in the context of the tidal stirring model for the formation of dwarf spheroidal galaxies in the Local Group (LG). Our simulations are designed to reproduce the tidal interactions between MW-sized host galaxies and rotationally supported dwarfs embedded in 10 9 M ☉ dark matter (DM) halos. We explore a variety of inner density slopes ρ∝r –α for the dwarf DM halos, ranging from core-like (α = 0.2) to cuspy (α = 1), and different dwarf orbital configurations. Our experiments demonstrate that UFDs can be produced via tidal stirring of disky dwarfs on relatively tight orbits, consistent with a redshift of accretion by the host galaxy of z ∼ 1, and with intermediate values for the halo inner density slopes (ρ∝r –0.6 ). The inferred slopes are in excellent agreement with those resulting from both the modeling of the rotation curves of dwarf galaxies and recent cosmological simulations of dwarf galaxy formation. Comparing the properties of observed UFDs with those of their simulated counterparts, we find remarkable similarities in terms of basic observational parameters. We conclude that tidal stirring of rotationally supported dwarfs represents a viable mechanism for the formation of UFDs in the LG environment.

  2. Scaling of confinement and profiles in the EXTRAP T2 reversed-field pinch

    Science.gov (United States)

    Welander, A.

    1999-01-01

    In the EXTRAP T2 reversed-field pinch the diagnostic techniques for the measurement of electron density and temperature include; Thomson scattering which gives values at three radial positions in the core (r/a = 0, 0.28, 0.56), Langmuir probes which give values at the edge (r/a > 0.9) and interferometry which gives a line-averaged density. The empirical scaling of electron density and temperature including profile information with global plasma parameters has been studied. The density profile is subject to large variations, with an average parabolic shape when the density is low and flatter shapes when the density is increased. The change in the profile shape can be attributed to a shift in the penetration length of neutrals from the vicinity of the wall. The temperature scales roughly as I/n1/2 where I is the plasma current and n is the density. The temperature profile is always quite flat with lower variations and there is a tendency for a flatter profile at higher temperatures.

  3. Anomalous length dependence of the conductance of graphene nanoribbons with zigzag edges

    KAUST Repository

    Bilić, Ante

    2013-01-01

    Charge transport through two sets of symmetric graphene nanoribbons with zigzag shaped edges in a two-terminal device has been investigated, using density functional theory combined with the non-equilibrium Green\\'s function method. The conductance has been explored as a function of nanoribbon length, bias voltage, and the strength of terminal coupling. The set of narrower nanoribbons, in the form of thiolated linear acenes, shows an anomalous length dependence of the conductance, which at first exhibits a drop and a minimum, followed by an evident rise. The length trend is shown to arise because of a gradual transformation in the transport mechanism, which changes from being governed by a continuum of out-of-plane π type and in-plane state channels to being fully controlled by a single, increasingly more resonant, occupied π state channel. For the set of nanoribbons with a wider profile, a steady increase is observed across the whole length range, owing to the absence of the former transport mechanism. The predicted trends are confirmed by the inclusion of self-interaction correction in the calculations. For both sets of nanoribbons the replacement of the strongly coupling thiol groups by weakly bonding phenathroline has been found to cause a strong attenuation with the length and a generally low conductance. © 2013 American Institute of Physics.

  4. The control of plasma density profile in Tore Supra. Comparison of different fueling techniques; Controle du profil de densite dans le plasma de Tore Supra. Comparaison de differentes methodes d'alimentation en particules

    Energy Technology Data Exchange (ETDEWEB)

    Commaux, N

    2007-09-15

    The behaviour of a reactor-class plasma when fuelled using the existing techniques (gas puffing, supersonic molecular beam injection and pellet injection) is still very difficult to foresee. The present work has been initiated on Tore Supra in order to extrapolate the consequences of the different fuelling systems on ITER. Two main topics have been studied: the comparison of the plasma behaviour when fuelled using the different techniques at high Greenwald density fractions and the study of the homogenization following a pellet injection (main fuelling technique for ITER burning plasmas). The experiments at high Greenwald density fractions performed on Tore Supra showed that the plasma behaviour is very dependent on the fuelling method. The plasma energy confinement is following the scaling laws determined at low density when fuelled using pellet injection. which is better than for gas puffing and SMBI. both inducing a significant confinement loss. This behaviour is nor related to a transport modification: the ratio between effective diffusion and convection is similar to the pellet case. The difference between these shots is related only to the position of the matter source (at the edge for gas and close to the center for pellets). The study concerning the homogenization phenomena following a pellet injection aims mainly to study the {nabla}B-drift effect that expels the mater deposited by a pellet toward the low field side. A new phenomenon. which appears to be particularly important for the {nabla}B-drift during low field side injections. was then discovered: the influence of magnetic surfaces with an integer-valued safety factor (q). When the mater drifting toward low field side crosses an integer q surface. it experiences an important braking effect which stops the drift motion. It implies that the pellet material is mainly deposited on the last integer q surface crossed by the pellet during its injection. This study allows also to determine that the {nabla

  5. Scrape-off layer profile modifications by convective cells

    International Nuclear Information System (INIS)

    Myra, J.R.; DIppolito, D.A.

    1996-01-01

    Convective cells (CC close-quote s) are important in understanding density profile modifications induced by ion cyclotron range of frequencies (ICRF) antennas. This has motivated the present work in which the effect of CC close-quote s on transport in the scrape-off layer is studied, in the regime where the density gradient scale length L n and the cell size L are comparable. Monte Carlo simulations show that closed cell convection acts to flatten the density profile, and that open cells enhance the particle flow to the wall, depleting the density and yielding profiles similar to those measured near ICRF antennas. A new one-dimensional, two-branch model of CC transport is shown to agree well with the simulations. The model gives rise to two characteristic scale lengths, only one of which is retained in the enhanced diffusion models that are applicable for L n >L. The two-branch model is expected to be useful in analyzing ICRF experiments. copyright 1996 American Institute of Physics

  6. High density lipoprotein structural changes and drug response in lipidomic profiles following the long-term fenofibrate therapy in the FIELD substudy.

    Directory of Open Access Journals (Sweden)

    Laxman Yetukuri

    Full Text Available In a recent FIELD study the fenofibrate therapy surprisingly failed to achieve significant benefit over placebo in the primary endpoint of coronary heart disease events. Increased levels of atherogenic homocysteine were observed in some patients assigned to fenofibrate therapy but the molecular mechanisms behind this are poorly understood. Herein we investigated HDL lipidomic profiles associated with fenofibrate treatment and the drug-induced Hcy levels in the FIELD substudy. We found that fenofibrate leads to complex HDL compositional changes including increased apoA-II, diminishment of lysophosphatidylcholines and increase of sphingomyelins. Ethanolamine plasmalogens were diminished only in a subgroup of fenofibrate-treated patients with elevated homocysteine levels. Finally we performed molecular dynamics simulations to qualitatively reconstitute HDL particles in silico. We found that increased number of apoA-II excludes neutral lipids from HDL surface and apoA-II is more deeply buried in the lipid matrix than apoA-I. In conclusion, a detailed molecular characterization of HDL may provide surrogates for predictors of drug response and thus help identify the patients who might benefit from fenofibrate treatment.

  7. On the use of the Prandtl mixing length model in the cutting torch modeling

    International Nuclear Information System (INIS)

    Mancinelli, B; Minotti, F O; Kelly, H

    2011-01-01

    The Prandtl mixing length model has been used to take into account the turbulent effects in a 30 A high-energy density cutting torch model. In particular, the model requires the introduction of only one adjustable coefficient c corresponding to the length of action of the turbulence. It is shown that the c value has little effect on the plasma temperature profiles outside the nozzle (the differences being less than 10 %), but severely affects the plasma velocity distribution, with differences reaching about 100% at the middle of the nozzle-anode gap. Within the experimental uncertainties it was also found that the value c = 0.08 allows to reproduce both, the experimental data of velocity and temperature

  8. "Depth-profiling" and quantitative characterization of the size, composition, shape, density, and morphology of fine particles with SPLAT, a single-particle mass spectrometer.

    Science.gov (United States)

    Zelenyuk, Alla; Yang, Juan; Song, Chen; Zaveri, Rahul A; Imre, Dan

    2008-01-31

    A significant fraction of atmospheric particles are composed of inorganic substances that are mixed or coated with organic compounds. The properties and behavior of these particles depend on the internal composition and arrangement of the specific constituents in each particle. It is important to know which constituent is on the surface and whether it covers the particle surface partially or entirely. We demonstrate here an instrument consisting of an ultrasensitive single-particle mass spectrometer coupled with a differential mobility analyzer to quantitatively measure in real time individual particle composition, size, density, and shape and to determine which substance is on the surface and whether it entirely covers the particle. For this study, we use NaCl particles completely coated with liquid dioctyl phthalate to generate spherical particles, and NaCl particles partially coated with pyrene, a solid poly aromatic hydrocarbon, to produce aspherical particles with pyrene nodules and an exposed NaCl core. We show that the behavior of the mass spectral intensities as a function of laser fluence yields information that can be used to determine the morphological distribution of individual particle constituents.

  9. Short cervical length dilemma.

    Science.gov (United States)

    Suhag, Anju; Berghella, Vincenzo

    2015-06-01

    Preterm birth (PTB) is a leading cause of neonatal morbidity and mortality. With research efforts, the rate of PTB decreased to 11.4% in 2013. Transvaginal ultrasound (TVU) cervical length (CL) screening predicts PTB. In asymptomatic singletons without prior spontaneous PTB (sPTB), TVU CL screening should be done. If the cervix is 20 mm or less, vaginal progesterone is indicated. In asymptomatic singletons with prior sPTB, serial CL screening is indicated. In multiple gestations, routine cervical screening is not indicated. In symptomatic women with preterm labor, TVU CL screening and fetal fibronectin testing is recommended. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. discouraged by queue length

    Directory of Open Access Journals (Sweden)

    P. R. Parthasarathy

    2001-01-01

    Full Text Available The transient solution is obtained analytically using continued fractions for a state-dependent birth-death queue in which potential customers are discouraged by the queue length. This queueing system is then compared with the well-known infinite server queueing system which has the same steady state solution as the model under consideration, whereas their transient solutions are different. A natural measure of speed of convergence of the mean number in the system to its stationarity is also computed.

  11. Primary length standard adjustment

    Science.gov (United States)

    Ševčík, Robert; Guttenová, Jana

    2007-04-01

    This paper deals with problems and techniques connected with primary length standard adjusting, which includes disassembling of the device and by use of the secondary laser with collimated beam and diffraction laws successively reassembling of the laser. In the reassembling process the device was enhanced with substituting the thermal grease cooling of cold finger by copper socket cooler. This improved external cooling system enables more effective cooling of molecular iodine in the cell, which allows better pressure stability of iodine vapor and easier readjustment of the system.

  12. Density functional theory and multiscale materials modeling

    Indian Academy of Sciences (India)

    In the macroscopic length scale, however, matter is usually treated as a continuous medium and a description using local mass density, energy density and other related density functions has been found to be quite appropriate. A unique single unified theoretical framework that emerges through the density concept at these ...

  13. Vertical profile of the specific surface area and density of the snow at Dome C and on a transect to Dumont D'Urville, Antarctica – albedo calculations and comparison to remote sensing products

    Directory of Open Access Journals (Sweden)

    J.-C. Gallet

    2011-08-01

    Full Text Available The specific surface area (SSA of snow determines in part the albedo of snow surfaces and the capacity of the snow to adsorb chemical species and catalyze reactions. Despite these crucial roles, almost no value of snow SSA are available for the largest permanent snow expanse on Earth, the Antarctic. We report the first extensive study of vertical profiles of snow SSA near Dome C (DC: 75°06' S, 123°20' E, 3233 m a.s.l. on the Antarctic plateau, and at seven sites during the logistical traverse between Dome C and the French coastal base Dumont D'Urville (DDU: 66°40' S, 140°01' E during the Austral summer 2008–2009. We used the DUFISSS system, which measures the IR reflectance of snow at 1310 nm with an integrating sphere. At DC, the mean SSA of the snow in the top 1 cm is 38 m2 kg−1, decreasing monotonically to 14 m2 kg−1 at a depth of 50 cm. Along the traverse, the snow SSA profile is similar to that at DC in the first 600 km from DC. Closer to DDU, the SSA of the top 5 cm is 23 m2 kg−1, decreasing to 19 m2 kg−1 at 50 cm depth. This difference is attributed to wind, which causes a rapid decrease of surface snow SSA, but forms hard windpacks whose SSA decrease more slowly with time. Since light-absorbing impurities are not concentrated enough to affect albedo, the vertical profiles of SSA and density were used to calculate the spectral albedo of the snow for several realistic illumination conditions, using the DISORT radiative transfer model. A preliminary comparison with MODIS data is presented and our calculations and MODIS data show similar trends.

  14. Road density

    Data.gov (United States)

    U.S. Environmental Protection Agency — Road density is generally highly correlated with amount of developed land cover. High road densities usually indicate high levels of ecological disturbance. More...

  15. Information-theoretic lengths of Jacobi polynomials

    Energy Technology Data Exchange (ETDEWEB)

    Guerrero, A; Dehesa, J S [Departamento de Fisica Atomica, Molecular y Nuclear, Universidad de Granada, Granada (Spain); Sanchez-Moreno, P, E-mail: agmartinez@ugr.e, E-mail: pablos@ugr.e, E-mail: dehesa@ugr.e [Instituto ' Carlos I' de Fisica Teorica y Computacional, Universidad de Granada, Granada (Spain)

    2010-07-30

    The information-theoretic lengths of the Jacobi polynomials P{sup ({alpha}, {beta})}{sub n}(x), which are information-theoretic measures (Renyi, Shannon and Fisher) of their associated Rakhmanov probability density, are investigated. They quantify the spreading of the polynomials along the orthogonality interval [- 1, 1] in a complementary but different way as the root-mean-square or standard deviation because, contrary to this measure, they do not refer to any specific point of the interval. The explicit expressions of the Fisher length are given. The Renyi lengths are found by the use of the combinatorial multivariable Bell polynomials in terms of the polynomial degree n and the parameters ({alpha}, {beta}). The Shannon length, which cannot be exactly calculated because of its logarithmic functional form, is bounded from below by using sharp upper bounds to general densities on [- 1, +1] given in terms of various expectation values; moreover, its asymptotics is also pointed out. Finally, several computational issues relative to these three quantities are carefully analyzed.

  16. Lung density

    DEFF Research Database (Denmark)

    Garnett, E S; Webber, C E; Coates, G

    1977-01-01

    The density of a defined volume of the human lung can be measured in vivo by a new noninvasive technique. A beam of gamma-rays is directed at the lung and, by measuring the scattered gamma-rays, lung density is calculated. The density in the lower lobe of the right lung in normal man during quiet...

  17. Density functional theory and multiscale materials modeling

    Indian Academy of Sciences (India)

    One of the vital ingredients in the theoretical tools useful in materials modeling at all the length scales of interest is the concept of density. In the microscopic length scale, it is the electron density that has played a major role in providing a deeper understanding of chemical binding in atoms, molecules and solids.

  18. Curvature profiles as initial conditions for primordial black hole formation

    International Nuclear Information System (INIS)

    Polnarev, Alexander G; Musco, Ilia

    2007-01-01

    This work is part of an ongoing research programme to study possible primordial black hole (PBH) formation during the radiation-dominated era of the early universe. Working within spherical symmetry, we specify an initial configuration in terms of a curvature profile, which represents initial conditions for the large amplitude metric perturbations, away from the homogeneous Friedmann-Robertson-Walker model, which are required for PBH formation. Using an asymptotic quasi-homogeneous solution, we relate the curvature profile with the density and velocity fields, which at an early enough time, when the length scale of the configuration is much larger than the cosmological horizon, can be treated as small perturbations of the background values. We present general analytic solutions for the density and velocity profiles. These solutions enable us to consider in a self-consistent way the formation of PBHs in a wide variety of cosmological situations with the cosmological fluid being treated as an arbitrary mixture of different components with different equations of state. We obtain the analytical solutions for the density and velocity profiles as functions of the initial time. We then use two different parametrizations for the curvature profile and follow numerically the evolution of initial configurations

  19. Correlation lengths of electrostatic turbulence

    International Nuclear Information System (INIS)

    Guiziou, L.; Garbet, X.

    1995-01-01

    This document deals with correlation length of electrostatic turbulence. First, the model of drift waves turbulence is presented. Then, the radial correlation length is determined analytically with toroidal coupling and non linear coupling. (TEC). 5 refs

  20. Direct Laser Writing of Low-Density Interdigitated Foams for Plasma Drive Shaping [Direct Laser Writing of Low Density Nanostitched Foams for Plasma Drive Shaping

    International Nuclear Information System (INIS)

    Oakdale, James S.; Smith, Raymond F.; Forien, Jean-Baptiste; Smith, William L.; Ali, Suzanne J.

    2017-01-01

    Monolithic porous bulk materials have many promising applications ranging from energy storage and catalysis to high energy density physics. High resolution additive manufacturing techniques, such as direct laser writing via two photon polymerization (DLW-TPP), now enable the fabrication of highly porous microlattices with deterministic morphology control. In this work, DLW-TPP is used to print millimeter-sized foam reservoirs (down to 0.06 g cm –3 ) with tailored density-gradient profiles, where density is varied by over an order of magnitude (for instance from 0.6 to 0.06 g cm –3 ) along a length of <100 µm. Taking full advantage of this technology, however, is a multiscale materials design problem that requires detailed understanding of how the different length scales, from the molecular level to the macroscopic dimensions, affect each other. The design of these 3D-printed foams is based on the brickwork arrangement of 100 × 100 × 16 µm 3 log-pile blocks constructed from sub-micrometer scale features. A block-to-block interdigitated stitching strategy is introduced for obtaining high density uniformity at all length scales. Lastly, these materials are used to shape plasma-piston drives during ramp-compression of targets under high energy density conditions created at the OMEGA Laser Facility.

  1. Correlation lengths of electrostatic turbulence

    International Nuclear Information System (INIS)

    Guiziou, L.; Garbet, X.

    1995-01-01

    In this paper, the radial correlation length of an electrostatic drift wave turbulence is analytically determined in various regimes. The analysis relies on the calculation of a range of mode non linear interaction, which is an instantaneous correlation length. The link with the usual correlation length has not been investigated yet. (TEC). 5 refs

  2. MODEL COMPARISON FOR THE DENSITY STRUCTURE ACROSS SOLAR CORONAL WAVEGUIDES

    Energy Technology Data Exchange (ETDEWEB)

    Arregui, I.; Asensio Ramos, A. [Instituto de Astrofísica de Canarias, Vía Láctea s/n, E-38205 La Laguna, Tenerife (Spain); Soler, R., E-mail: iarregui@iac.es [Solar Physics Group, Departament de Física, Universitat de les Illes Balears, E-07122 Palma de Mallorca (Spain)

    2015-10-01

    The spatial variation of physical quantities, such as the mass density, across solar atmospheric waveguides governs the timescales and spatial scales for wave damping and energy dissipation. The direct measurement of the spatial distribution of density, however, is difficult, and indirect seismology inversion methods have been suggested as an alternative. We applied Bayesian inference, model comparison, and model-averaging techniques to the inference of the cross-field density structuring in solar magnetic waveguides using information on periods and damping times for resonantly damped magnetohydrodynamic transverse kink oscillations. Three commonly employed alternative profiles were used to model the variation of the mass density across the waveguide boundary. Parameter inference enabled us to obtain information on physical quantities such as the Alfvén travel time, the density contrast, and the transverse inhomogeneity length scale. The inference results from alternative density models were compared and their differences quantified. Then, the relative plausibility of the considered models was assessed by performing model comparison. Our results indicate that the evidence in favor of any of the three models is minimal, unless the oscillations are strongly damped. In such a circumstance, the application of model-averaging techniques enables the computation of an evidence-weighted inference that takes into account the plausibility of each model in the calculation of a combined inversion for the unknown physical parameters.

  3. Localized Density/Drag Prediction for Improved Onboard Orbit Propagation

    Science.gov (United States)

    Stastny, N.; Lin, C.; Lovell, A.; Luck, J.; Chavez, F.

    Since the development of Luigi G. Jacchia's first density model in 1970 (J70), atmospheric density modeling has steadily focused on large monolithic codes that provide global density coverage. The most recent instantiation of the global density model is the Jacchia-Bowman 2008 (JB08) model developed by Bruce Bowman of the Air Force Space Command. As the models have evolved and improved, their complexity has grown as well. Where the J70 model required 2 indices and various time averages to determine density, the JB08 model requires 5 indices to determine density. Due to computational complexity, the number of real-time inputs required, and limited forecasting abilities, these models are not well suited for onboard satellite orbit propagation. In contrast to the global models, this paper proposes the development of a density prediction tool that is only concerned with the trajectory of a specific satellite. Since the orbital parameters of most low Earth orbiting satellites remain relatively constant in the short term, there is also minimal variation in the density profile observed by the satellite. Limiting the density model to a smaller orbit regime will also increase the ability to forecast the density along that orbital track. As a first step, this paper evaluates the feasibility of using a localized density prediction algorithm to generate the density profile that will be seen by satellite, allowing for high-accuracy orbit propagation with minimal or no input from the ground. The algorithm evaluated in this paper is a simple Yule-Walker auto-regressive filter that, given previously measured density values, provides predictions on the upcoming density profile. This first approach requires zero information about the satellite's current orbit, but does require an onboard method for determining the current, local density. Though this aspect of the onboard system is not analyzed here, it is envisioned that this current, local density (or equivalently drag acceleration

  4. Development of a heterodyne micro-wave reflectometer with ultra-fast sweeping. The study of the plasma turbulence influence on the measurements of electron density profile; Developppement d`un reflectometre micro-onde heterodyne a balayage ultra rapide. Etude de l`influence de la turbulence du plasma sur la mesure des profils de densite electronique

    Energy Technology Data Exchange (ETDEWEB)

    Moreau, Philippe [Aix-Marseille-1 Univ., 13 - Marseille (France)

    1997-10-17

    The density profile of the fusion plasmas can be investigated by the reflectometry diagnostics. The measurement principle is based on the radar techniques which calculate the phase shift of a millimeter wave propagating into the plasma and reflected at a cut-off layer. However, this propagation is perturbed by the plasma turbulence. These phenomena affect the phase delay measurement by not well understood a process. In this work we have tried to find the mechanisms and origin of the turbulence which is responsible for the phase disturbance. We point out the role of collisionality and plasma radiation in controlling the instability and also, demonstrate that the phase delay of the probing wave is very sensitive to the plasma MHD phenomena and is less affected by the micro-turbulence. The second part of this work is the development and the use of a new heterodyne reflectometer. The principal characteristics are given. Its heterodyne detection allows the separation of phase and amplitude information from the detected signal and then to study their contribution to the mechanism of signal perturbation. The use of this reflectometer allows us to point out the following points: - a high dynamic availability, required by the large amplitude drops, often greater than 30 db; - fast sweep operation requirement to `freeze` the plasma turbulence; - multiple reflection effects which modulate the amplitude and phase of the probing wave if they are not suppressed by filtering the detected signal; - very good localisation of the measurement (of the order of millimeter). The heterodyne reflectometer developed during this work offers several advantages of different distinct reflectometry techniques (fast sweep, absolute and differential phase measurements, heterodyne detection). It could be developed to work over higher frequency range so as to measure density profile over larger radial extension with very high performances. (author) 93 refs., 101 figs., 8 tabs. 3 ills.

  5. Local Variability in Firn Layering and Compaction Rates Using GPR Data, Depth-Density Profiles, and In-Situ Reflectors in the Dry Snow Zone Near Summit Station, Greenland

    Science.gov (United States)

    Lines, A.; Elliott, J.; Ray, L.; Albert, M. R.

    2017-12-01

    Understanding the surface mass balance (SMB) of the Greenland ice sheet is critical to evaluating its response to a changing climate. A key factor in translating satellite and airborne elevation measurements of the ice sheet to SMB is understanding natural variability of firn layer depth and the relative compaction rate of these layers. A site near Summit Station, Greenland was chosen to investigate the variation in layering across a 100m by 100m grid using a 900 MHz and a 2.6 GHz ground penetrating radar (GPR) antenna. These radargrams were ground truthed by taking depth density profiles of five 2m snow pits and five 5m firn cores within the 100m by 100m grid. Combining these measurements with the accumulation data from the nearby ICECAPS weekly bamboo forest measurements, it's possible to see how the snow deposition from individual storm events can vary over a small area. Five metal reflectors were also placed on the surface of the snow in the bounds of the grid to serve as reference reflectors for similar measurements that will be taken in the 2018 field season at Summit Station. This will assist in understanding how one year of accumulation in the dry snow zone impacts compaction and how this rate can vary over a small area.

  6. Blood chemistry profile of Surubim hybrid fish (Pseudoplatystoma reticulatum X P. corruscans raised in different stocking densities Perfil bioquímico do híbrido de Surubim (Pseudoplatystoma reticulatum X P. corruscans criado em diferentes densidades

    Directory of Open Access Journals (Sweden)

    Carla Rosa Labarrère

    2013-06-01

    Full Text Available Massive production, such as fish growing in water recirculation system, imposes challenges to animals capable of altering their homeostatic balance, and is able to affect their physiological performance. Therefore, the levels of ions and serum enzymes can be used as indicators of fish health. This study aimed to analyze the blood biochemistry profile of hybrid surubim (P. reticulatum X P. corruscans submitted to different stocking densities in water recirculation system, in two distinct stages of production, from 150 to 400 g (first trial, and 400 to 1000 g (second trial. In the first trial, the five stocking rates were: 27.5, 47.5, 67.5, 87.5 and 107.5 fish/m³ of water. To obtain these densities, it was used 11, 19, 27, 35 and 43 fish per tank, respectively. In the second trial, five stocking rates were: 10, 20, 30, 40 and 50 fish/m³ of water. To obtain these densities we used 4, 8, 12, 16 and 20 fish per tank, respectively. The concentrations of glucose, cholesterol, triglycerides, urea, creatinine, alkaline phosphatase (ALP, aspartate aminotransferase (AST, lactate dehydrogenase (LDH, calcium, phosphorus, potassium and magnesium were obtained. Only urea concentrations in first trial and ALP and AST concentrations in second trial were influenced by stocking density, presenting a significant difference between groups. Thus, in both trials the hybrid fish studied maintained homeostasis when reared in different stocking densities.Dentre os sistemas de produção, o de recirculação de água impõe desafios para os animais que podem ser capazes de alterar o seu equilíbrio homeostático, afetando o índice de desempenho. Por conseguinte, os níveis de ions e enzimas séricas podem ser utilizados como indicadores de saúde dos peixes. Neste estudo, objetivo-se analisar o perfil de bioquímico do sangue do híbrido de Surubim (P. reticulatum X P. corruscans, submetido a diferentes densidades de estocagem em sistema de recirculação de água, em

  7. High density LHCD experiments and recent progress on HT-7 superconducting tokamak

    International Nuclear Information System (INIS)

    2000-01-01

    The quasi-steady state (τ H > 10 τ Eoh ) H-mode was obtained with very high plasma density by Lower Hybrid Current Drive (LHCD). The line average density during improved confinement phase is about 4.5∼6.0x10 13 cm -3 which is very close to the Greenwald density limit (78 ∼ 96% of Greenwald density limit). The τ E is about 1.5 ∼ 2.0 times than the L-mode scaling during H-phase. The experimental results show a good agreement with code simulation for the LH off-axis power deposition profile with a reproducible manner. These off-axis hollow current profiles and enhanced confinement improvements are attributed to a strong reduction of electron thermal diffusivity in the reversed shear region. Steady state full LH wave current drive has been achieved. The pulse length is 3.5 seconds, which reaches the present limit of PF system. The good plasma condition is obtained by ICRF boronization, which makes Z eff close to 1.0. High density shots are obtained by two different fueling methods: multi pellet injection and supersonic beam injection. The later shows a high fueling efficiency that could be used for steady-state operation and the plasma density exceeds the Greenwald density limit. ICRH preionization, start-up, heating and its synergy with LHCD have been tested during recent experiments and some interesting results have been obtained. (author)

  8. 7 Length-weight relationship

    African Journals Online (AJOL)

    Administrator

    Length-weight measurements were taken from well-preserved fish specimens from which stomachs were extracted for the analysis of the food contents, using frequency of occurrence, numerical and gravimetric methods, as well as index of relative importance. The length-frequency analysis showed a size distribution with a ...

  9. Comparison of fiber length analyzers

    Science.gov (United States)

    Don Guay; Nancy Ross Sutherland; Walter Rantanen; Nicole Malandri; Aimee Stephens; Kathleen Mattingly; Matt Schneider

    2005-01-01

    In recent years, several fiber new fiber length analyzers have been developed and brought to market. The new instruments provide faster measurements and the capability of both laboratory and on-line analysis. Do the various fiber analyzers provide the same length, coarseness, width, and fines measurements for a given fiber sample? This paper provides a comparison of...

  10. Profile consistency on TFTR

    International Nuclear Information System (INIS)

    Fredrickson, E.D.; McGuire, K.M.; Goldston, R.J.

    1987-01-01

    Electron heat transport on TFTR and other tokamaks is several orders of magnitude larger than neoclassical calculations predict. Despite considerable effort, there is still no clear theoretical understanding of this anomalous transport. The electron temperature profile, T e (r), has shown a marked consistency on many machines for a wide range of plasma parameters and heating profiles. This could be an important clue as to the process responsible for this enhanced thermal transport. In the first section of the paper the result is presented that TFTR electron temperature profile shapes are even more constrained than previous models of profile consistency suggested. The profile shapes, T e (r)/T e (a/2), are found to be invariant (for r>0.4 a) for a wide range of parameters, including q(a). In the second section, an experiment is discussed which uses a fast current ramp to transiently decouple the current density profile, J(r), and the T e (r) profiles. From this experiment, it has been determined that the J(r) profile can be strongly modified with no measureable effect on the electron temperature profile shape. Thus, while the electron temperature profile is apparently constrained, the current profile is not. (author). Letter-to-the-editor. 25 refs, 9 figs

  11. Electron Bunch Length Diagnostic With Coherent Smith-Purcell Radiation

    International Nuclear Information System (INIS)

    Nguyen, D.C.

    1997-01-01

    The authors have designed a new technique for measuring subpicosecond electron bunch lengths using coherent Smith-Purcell radiation. This new diagnostic technique involves passing the electron beam in close proximity of a grating with a period comparable to the electron bunch length. The emitted Smith-Purcell radiation will have a coherent component whose angular position and distribution are directly related to the electron bunch length and longitudinal profile, respectively. This new diagnostic technique is inherently simple, inexpensive and non-intercepting. The authors show that the new technique is also scaleable to femtosecond regime

  12. Tomography of the ionospheric electron density with geostatistical inversion

    Directory of Open Access Journals (Sweden)

    D. Minkwitz

    2015-08-01

    Full Text Available In relation to satellite applications like global navigation satellite systems (GNSS and remote sensing, the electron density distribution of the ionosphere has significant influence on trans-ionospheric radio signal propagation. In this paper, we develop a novel ionospheric tomography approach providing the estimation of the electron density's spatial covariance and based on a best linear unbiased estimator of the 3-D electron density. Therefore a non-stationary and anisotropic covariance model is set up and its parameters are determined within a maximum-likelihood approach incorporating GNSS total electron content measurements and the NeQuick model as background. As a first assessment this 3-D simple kriging approach is applied to a part of Europe. We illustrate the estimated covariance model revealing the different correlation lengths in latitude and longitude direction and its non-stationarity. Furthermore, we show promising improvements of the reconstructed electron densities compared to the background model through the validation of the ionosondes Rome, Italy (RO041, and Dourbes, Belgium (DB049, with electron density profiles for 1 day.

  13. Spin-Charge Separation in Finite Length Metallic Carbon Nanotubes

    KAUST Repository

    Zhang, Yongyou

    2017-10-17

    Using time-dependent density functional theory, we study the optical excitations in finite length carbon nanotubes. Evidence of spin-charge separation is given in the spacetime domain. We demonstrate that the charge density wave is due to collective excitations of electron singlets, while the accompanying spin density wave is due to those of electron triplets. The Tomonaga–Luttinger liquid parameter and density–density interaction are extrapolated from the first-principles excitation energies. We show that the density–density interaction increases with the length of the nanotube. The singlet and triplet excitation energies, on the other hand, decrease for increasing length of the nanotube. Their ratio is used to establish a first-principles approach for deriving the Tomonaga–Luttinger parameter (in excellent agreement with experimental data). Time evolution analysis of the charge and spin line densities evidences that the charge and spin density waves are elementary excitations of metallic carbon nanotubes. Their dynamics show no dependence on each other.

  14. Density structures inside the plasmasphere: Cluster observations

    DEFF Research Database (Denmark)

    Darrouzet, F.; Decreau, P.M.E.; De Keyser, J.

    2004-01-01

    The electron density profiles derived from the EFW and WHISPER instruments on board the four Cluster spacecraft reveal density structures inside the plasmasphere and at its outer boundary, the plasmapause. We have conducted a statistical study to characterize these density structures. We focus on...

  15. Impact of Cyclic Prefix length on OFDM system Capacity

    DEFF Research Database (Denmark)

    Rom, Christian; Sørensen, Troels Bundgaard; Mogensen, Preben Elgaard

    2005-01-01

    This paper is a study on the impact of the Cyclic Prefix (CP) length on the downlink Capacity in a base-band synchronized SISO-OFDM context. To measure this impact, the capacity, measured in bits per second per hertz, is chosen as quality parameter. The study shows how the lengthening of the CP......) the useful OFDM symbol duration, 2) the Signal to Noise Ratio (SNR) at the receiver and 3) the channel Power Delay Profile (PDP). Depending on the values of these parameters different optimum CP lengths are obtained. For a system using only one value of CP length we suggest an optimum value to be 4us...... for an OFDM symbol length of 40us and 6us for an OFDM symbol length of 80us....

  16. Low Bone Density

    Science.gov (United States)

    ... Bone Density Exam/Testing › Low Bone Density Low Bone Density Low bone density is when your bone ... to people with normal bone density. Detecting Low Bone Density A bone density test will determine whether ...

  17. Electron plasma oscillations at arbitrary Debye lengths

    International Nuclear Information System (INIS)

    Lehnert, B.

    1990-12-01

    A solution is presented for electron plasma oscillation in a thermalized homogeneous plasma, at arbitrary ratios between the Debye length λ D and the perturbation wave length λ. The limit λ D D >> λ corresponds to the free-streaming limit of strong kinetic phase-mixing due to large particle excursions. A strong large Debye distance (LDD) effect already appears when λ D > approx λ. The initial amplitude of the fluid-like contribution to the macroscopic density perturbation then becomes small as compared to the contribution from the free-streaming part. As a consequence, only a small fraction of the density perturbation remains after a limited number of kinetic damping times of the free-streaming part. The analysis further shows that a representation in terms of normal model of the form exp(-iωt) leads to amplitude factors of these modes which are related to each other and which depend on the combined free-streaming and fluid behaviour of the plasma. Consequently, these modes are coupled and cannot be treated as being independent of each other. (au)

  18. A pedagogical look at Jeans' density scale

    International Nuclear Information System (INIS)

    Chu, K-H W

    2007-01-01

    We illustrate the derivations of Jeans' criteria for the gravitational instabilities in a static homogeneous Newtonian system for pedagogical objectives. The critical Jeans density surface is presented in terms of dimensionless sound speeds and (characteristic) length scales

  19. Hydrogen concentration and mass density of diamondlike carbon films obtained by x-ray and neutron reflectivity

    DEFF Research Database (Denmark)

    Findeisen, E.; Feidenhans'l, R.; Vigild, Martin Etchells

    1994-01-01

    the mass density, but also the concentration of hydrogen, which varies in our case between 0 and 30 at.%. This method is a new and nondestructive way to determine the concentration of hydrogen within an error of less than 2 at.% in samples with sharp interfaces. It is especially suited for diamondlike......Specular reflectivity of neutrons and x rays can be used to determine the scattering length density profile of a material perpendicular to its surface. We have applied these techniques to study amorphous, diamondlike, hydrocarbon films. By the combination of these two techniques we obtain not only...

  20. Deep sea animal density and size estimated using a Dual-frequency IDentification SONar (DIDSON) offshore the island of Hawaii

    Science.gov (United States)

    Giorli, Giacomo; Drazen, Jeffrey C.; Neuheimer, Anna B.; Copeland, Adrienne; Au, Whitlow W. L.

    2018-01-01

    Pelagic animals that form deep sea scattering layers (DSLs) represent an important link in the food web between zooplankton and top predators. While estimating the composition, density and location of the DSL is important to understand mesopelagic ecosystem dynamics and to predict top predators' distribution, DSL composition and density are often estimated from trawls which may be biased in terms of extrusion, avoidance, and gear-associated biases. Instead, location and biomass of DSLs can be estimated from active acoustic techniques, though estimates are often in aggregate without regard to size or taxon specific information. For the first time in the open ocean, we used a DIDSON sonar to characterize the fauna in DSLs. Estimates of the numerical density and length of animals at different depths and locations along the Kona coast of the Island of Hawaii were determined. Data were collected below and inside the DSLs with the sonar mounted on a profiler. A total of 7068 animals were counted and sized. We estimated numerical densities ranging from 1 to 7 animals/m3 and individuals as long as 3 m were detected. These numerical densities were orders of magnitude higher than those estimated from trawls and average sizes of animals were much larger as well. A mixed model was used to characterize numerical density and length of animals as a function of deep sea layer sampled, location, time of day, and day of the year. Numerical density and length of animals varied by month, with numerical density also a function of depth. The DIDSON proved to be a good tool for open-ocean/deep-sea estimation of the numerical density and size of marine animals, especially larger ones. Further work is needed to understand how this methodology relates to estimates of volume backscatters obtained with standard echosounding techniques, density measures obtained with other sampling methodologies, and to precisely evaluate sampling biases.

  1. Effect of sodium fluoride on bone density in chickens.

    Science.gov (United States)

    Lundy, M W; Russell, J E; Avery, J; Wergedal, J E; Baylink, D J

    1992-05-01

    In addition to increasing bone volume, fluoride has been demonstrated to increase ash weight and mineral density. To determine whether newly formed or older bone is most affected by fluoride treatment, bone from chickens receiving fluoridated water was fractionated into lower density (recently formed) and higher density (more mature) specific gravity fractions. Fluoride was administered to the chickens for different lengths of time (4 or 13 weeks) or at varying doses for a 4-week period (0, 4.2, 16.8 mmol/liter drinking water). Fluoride treatment caused a shift in the mineral density profile, showing an increased proportion of mineral distribution in the more mature, higher density fractions. To determine whether this density gradient shift was due to increased maturation rate of bone or decreased resorption and mineralization rates, [3H]proline and 45Ca were injected 5 days and 24 hours prior to sacrifice, respectively. The distributions of both 3H or 45Ca, as percentages of total counts incorporated, were shifted by fluoride treatment into more mature, higher density fractions. Expressing the number of counts as a percent of the bone in each fraction (total hydroxyproline or Ca) revealed an increased incorporation of both 3H and 45Ca into the higher specific gravity fractions 2.0-2.2. These results suggest that fluoride treatment increases bone maturation and the rate of secondary mineralization in the cortical bone. Such changes in the quality of more mature, well-mineralized bone, in humans as well as animals, may have a significant influence on brittleness and strength.

  2. The ideal dimensions of a Halbach cylinder of finite length

    DEFF Research Database (Denmark)

    Bjørk, Rasmus

    2011-01-01

    In this paper the smallest or optimal dimensions of a Halbach cylinder of a finite length for a given sample volume and desired flux density are determined using numerical modeling and parameter variation. A sample volume that is centered in and shaped as the Halbach cylinder bore but with a poss...

  3. Experimental observations of anomalous potential drops over ion density cavities

    International Nuclear Information System (INIS)

    Bohm, M.

    1991-08-01

    Experiments are reported showing the plasma potential response when a step voltage is applied over the plasma column between the two plasma sources in a triple plasma machine. The time resolution is sufficient to resolve potential variations caused essentially by the electron motion, and two independent probe methods are used to obtain this time resolution. Depending on the initial conditions two different responses were observed on the time scale of the electron motion. When the initial ion density varies along the plasma column and has a local minimum (that is, forms an ion density cavity), the applied potential drop becomes distributed over the cavity after a few electron transit times. Later the profile steepens to a double layer on the time scale of the ion motion. The width of the cavity is comparable to the length of the plasma column. When the initial density is axially uniform, most of the potential drop instead concentrates to a narrow region at the low potential end of the plasma column after a few electron transit times. On the time scale of the ion motion this potential drop begins to propagate into the plasma as a double layer. The results obtained are consistent with those from numerical simulations with similar boundary conditions. Further experiments are necessary to get conclusive insight into the voltage supporting capability of an ion density cavity. (au) (34 refs.)

  4. CEBAF Upgrade Bunch Length Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Mahmoud [Old Dominion Univ., Norfolk, VA (United States)

    2016-05-01

    Many accelerators use short electron bunches and measuring the bunch length is important for efficient operations. CEBAF needs a suitable bunch length because bunches that are too long will result in beam interruption to the halls due to excessive energy spread and beam loss. In this work, bunch length is measured by invasive and non-invasive techniques at different beam energies. Two new measurement techniques have been commissioned; a harmonic cavity showed good results compared to expectations from simulation, and a real time interferometer is commissioned and first checkouts were performed. Three other techniques were used for measurements and comparison purposes without modifying the old procedures. Two of them can be used when the beam is not compressed longitudinally while the other one, the synchrotron light monitor, can be used with compressed or uncompressed beam.

  5. Continuously variable focal length lens

    Science.gov (United States)

    Adams, Bernhard W; Chollet, Matthieu C

    2013-12-17

    A material preferably in crystal form having a low atomic number such as beryllium (Z=4) provides for the focusing of x-rays in a continuously variable manner. The material is provided with plural spaced curvilinear, optically matched slots and/or recesses through which an x-ray beam is directed. The focal length of the material may be decreased or increased by increasing or decreasing, respectively, the number of slots (or recesses) through which the x-ray beam is directed, while fine tuning of the focal length is accomplished by rotation of the material so as to change the path length of the x-ray beam through the aligned cylindrical slows. X-ray analysis of a fixed point in a solid material may be performed by scanning the energy of the x-ray beam while rotating the material to maintain the beam's focal point at a fixed point in the specimen undergoing analysis.

  6. Overview of bunch length measurements

    International Nuclear Information System (INIS)

    Lumpkin, A. H.

    1999-01-01

    An overview of particle and photon beam bunch length measurements is presented in the context of free-electron laser (FEL) challenges. Particle-beam peak current is a critical factor in obtaining adequate FEL gain for both oscillators and self-amplified spontaneous emission (SASE) devices. Since measurement of charge is a standard measurement, the bunch length becomes the key issue for ultrashort bunches. Both time-domain and frequency-domain techniques are presented in the context of using electromagnetic radiation over eight orders of magnitude in wavelength. In addition, the measurement of microbunching in a micropulse is addressed

  7. Kondo length in bosonic lattices

    Science.gov (United States)

    Giuliano, Domenico; Sodano, Pasquale; Trombettoni, Andrea

    2017-09-01

    Motivated by the fact that the low-energy properties of the Kondo model can be effectively simulated in spin chains, we study the realization of the effect with bond impurities in ultracold bosonic lattices at half filling. After presenting a discussion of the effective theory and of the mapping of the bosonic chain onto a lattice spin Hamiltonian, we provide estimates for the Kondo length as a function of the parameters of the bosonic model. We point out that the Kondo length can be extracted from the integrated real-space correlation functions, which are experimentally accessible quantities in experiments with cold atoms.

  8. Polysome Profile Analysis - Yeast

    Czech Academy of Sciences Publication Activity Database

    Pospíšek, M.; Valášek, Leoš Shivaya

    2013-01-01

    Roč. 530, č. 2013 (2013), s. 173-181 ISSN 0076-6879 Institutional support: RVO:61388971 Keywords : grow yeast cultures * polysome profile analysis * sucrose density gradient centrifugation Subject RIV: CE - Biochemistry Impact factor: 2.194, year: 2013

  9. Density games.

    Science.gov (United States)

    Novak, Sebastian; Chatterjee, Krishnendu; Nowak, Martin A

    2013-10-07

    The basic idea of evolutionary game theory is that payoff determines reproductive rate. Successful individuals have a higher payoff and produce more offspring. But in evolutionary and ecological situations there is not only reproductive rate but also carrying capacity. Individuals may differ in their exposure to density limiting effects. Here we explore an alternative approach to evolutionary game theory by assuming that the payoff from the game determines the carrying capacity of individual phenotypes. Successful strategies are less affected by density limitation (crowding) and reach higher equilibrium abundance. We demonstrate similarities and differences between our framework and the standard replicator equation. Our equation is defined on the positive orthant, instead of the simplex, but has the same equilibrium points as the replicator equation. Linear stability analysis produces the classical conditions for asymptotic stability of pure strategies, but the stability properties of internal equilibria can differ in the two frameworks. For example, in a two-strategy game with an internal equilibrium that is always stable under the replicator equation, the corresponding equilibrium can be unstable in the new framework resulting in a limit cycle. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

  10. Absolute density measurements in the middle atmosphere

    Directory of Open Access Journals (Sweden)

    M. Rapp

    2001-05-01

    Full Text Available In the last ten years a total of 25 sounding rockets employing ionization gauges have been launched at high latitudes ( ~ 70° N to measure total atmospheric density and its small scale fluctuations in an altitude range between 70 and 110 km. While the determination of small scale fluctuations is unambiguous, the total density analysis has been complicated in the past by aerodynamical disturbances leading to densities inside the sensor which are enhanced compared to atmospheric values. Here, we present the results of both Monte Carlo simulations and wind tunnel measurements to quantify this aerodynamical effect. The comparison of the resulting ‘ram-factor’ profiles with empirically determined density ratios of ionization gauge measurements and falling sphere measurements provides excellent agreement. This demonstrates both the need, but also the possibility, to correct aerodynamical influences on measurements from sounding rockets. We have determined a total of 20 density profiles of the mesosphere-lower-thermosphere (MLT region. Grouping these profiles according to season, a listing of mean density profiles is included in the paper. A comparison with density profiles taken from the reference atmospheres CIRA86 and MSIS90 results in differences of up to 40%. This reflects that current reference atmospheres are a significant potential error source for the determination of mixing ratios of, for example, trace gas constituents in the MLT region.Key words. Middle atmosphere (composition and chemistry; pressure, density, and temperature; instruments and techniques

  11. Absolute density measurements in the middle atmosphere

    Directory of Open Access Journals (Sweden)

    M. Rapp

    Full Text Available In the last ten years a total of 25 sounding rockets employing ionization gauges have been launched at high latitudes ( ~ 70° N to measure total atmospheric density and its small scale fluctuations in an altitude range between 70 and 110 km. While the determination of small scale fluctuations is unambiguous, the total density analysis has been complicated in the past by aerodynamical disturbances leading to densities inside the sensor which are enhanced compared to atmospheric values. Here, we present the results of both Monte Carlo simulations and wind tunnel measurements to quantify this aerodynamical effect. The comparison of the resulting ‘ram-factor’ profiles with empirically determined density ratios of ionization gauge measurements and falling sphere measurements provides excellent agreement. This demonstrates both the need, but also the possibility, to correct aerodynamical influences on measurements from sounding rockets. We have determined a total of 20 density profiles of the mesosphere-lower-thermosphere (MLT region. Grouping these profiles according to season, a listing of mean density profiles is included in the paper. A comparison with density profiles taken from the reference atmospheres CIRA86 and MSIS90 results in differences of up to 40%. This reflects that current reference atmospheres are a significant potential error source for the determination of mixing ratios of, for example, trace gas constituents in the MLT region.

    Key words. Middle atmosphere (composition and chemistry; pressure, density, and temperature; instruments and techniques

  12. Bunch Length Measurements using Coherent Radiation

    CERN Document Server

    Ischebeck, Rasmus; Barnes, Christopher; Blumenfeld, Ian; Clayton, Chris; Decker, Franz Josef; Deng, Suzhi; Hogan, Mark; Huang Cheng Kun; Iverson, Richard; Johnson, Devon K; Krejcik, Patrick; Lu, Wei; Marsh, Kenneth; Oz, Erdem; Siemann, Robert; Walz, Dieter

    2005-01-01

    The accelerating field that can be obtained in a beam-driven plasma wakefield accelerator depends on the current of the electron beam that excites the wake. In the E-167 experiment, a peak current above 10kA will be delivered at a particle energy of 28GeV. The bunch has a length of a few ten micrometers and several methods are used to measure its longitudinal profile. Among these, autocorrelation of coherent transition radiation (CTR) is employed. The beam passes a thin metallic foil, where it emits transition radiation. For wavelengths greater than the bunch length, this transition radiation is emitted coherently. This amplifies the long-wavelength part of the spectrum. A scanning Michelson interferometer is used to autocorrelate the CTR. However, this method requires the contribution of many bunches to build an autocorrelation trace. The measurement is influenced by the transmission characteristics of the vacuum window and beam splitter. We present here an analysis of materials, as well as possible layouts ...

  13. Measurement of the diffusion length of thermal neutrons inside graphite

    International Nuclear Information System (INIS)

    Ertaud, A.; Beauge, R.; Fauquez, H.; De Laboulay, H.; Mercier, C.; Vautrey, L.

    1948-11-01

    The diffusion length of thermal neutrons inside a given industrial graphite is determined by measuring the neutron density inside a parallelepipedal piling up of graphite bricks (2.10 x 2.10 x 2.442 m). A 3.8 curies (Ra α → Be) source is placed inside the parallelepipedal block of graphite and thin manganese detectors are used. Corrections are added to the unweighted measurements to take into account the effects of the damping of supra-thermal neutrons in the measurement area. These corrections are experimentally deduced from the differential measurements made with a cadmium screen interposed between the source and the first plane of measurement. An error analysis completes the report. The diffusion length obtained is: L = 45.7 cm ± 0.3. The average density of the graphite used is 1.76 and the average apparent density of the piling up is 1.71. (J.S.)

  14. Cyclic codes of length 2

    Indian Academy of Sciences (India)

    Springer Verlag Heidelberg #4 2048 1996 Dec 15 10:16:45

    [X]/〈X2m. − 1〉 are given. Cyclic codes of length 2m over the finite field Fq, of odd characteristic, are defined in terms of their generator polynomials. The exact minimum distance and the dimension of the codes are obtained. Keywords.

  15. Diet, nutrition and telomere length.

    Science.gov (United States)

    Paul, Ligi

    2011-10-01

    The ends of human chromosomes are protected by DNA-protein complexes termed telomeres, which prevent the chromosomes from fusing with each other and from being recognized as a double-strand break by DNA repair proteins. Due to the incomplete replication of linear chromosomes by DNA polymerase, telomeric DNA shortens with repeated cell divisions until the telomeres reach a critical length, at which point the cells enter senescence. Telomere length is an indicator of biological aging, and dysfunction of telomeres is linked to age-related pathologies like cardiovascular disease, Parkinson disease, Alzheimer disease and cancer. Telomere length has been shown to be positively associated with nutritional status in human and animal studies. Various nutrients influence telomere length potentially through mechanisms that reflect their role in cellular functions including inflammation, oxidative stress, DNA integrity, DNA methylation and activity of telomerase, the enzyme that adds the telomeric repeats to the ends of the newly synthesized DNA. Copyright © 2011 Elsevier Inc. All rights reserved.

  16. Fractional baud-length coding

    Directory of Open Access Journals (Sweden)

    J. Vierinen

    2011-06-01

    Full Text Available We present a novel approach for modulating radar transmissions in order to improve target range and Doppler estimation accuracy. This is achieved by using non-uniform baud lengths. With this method it is possible to increase sub-baud range-resolution of phase coded radar measurements while maintaining a narrow transmission bandwidth. We first derive target backscatter amplitude estimation error covariance matrix for arbitrary targets when estimating backscatter in amplitude domain. We define target optimality and discuss different search strategies that can be used to find well performing transmission envelopes. We give several simulated examples of the method showing that fractional baud-length coding results in smaller estimation errors than conventional uniform baud length transmission codes when estimating the target backscatter amplitude at sub-baud range resolution. We also demonstrate the method in practice by analyzing the range resolved power of a low-altitude meteor trail echo that was measured using a fractional baud-length experiment with the EISCAT UHF system.

  17. Femur length and biparietal diameter

    African Journals Online (AJOL)

    2014-12-02

    Dec 2, 2014 ... Shipp TD, Bromley B, Mascola M, Benacerraf B. Variation in fetal femur length with respect to maternal race. J Ultrasound Med 2001;20:141‑4. 25. Deter RL, Harrist RB, Birnholz JC, Hadlock FP. Quantitative Obstetrical. Ultrasonography. New York: Wiley; 1986. 26. Yeh MN, Bracero L, Reilly KB, Murtha L, ...

  18. The Distribution of Lightning Channel Lengths in Northern Alabama Thunderstorms

    Science.gov (United States)

    Peterson, H. S.; Koshak, W. J.

    2010-01-01

    Lightning is well known to be a major source of tropospheric NOx, and in most cases is the dominant natural source (Huntreiser et al 1998, Jourdain and Hauglustaine 2001). Production of NOx by a segment of a lightning channel is a function of channel segment energy density and channel segment altitude. A first estimate of NOx production by a lightning flash can be found by multiplying production per segment [typically 104 J/m; Hill (1979)] by the total length of the flash s channel. The purpose of this study is to determine average channel length for lightning flashes near NALMA in 2008, and to compare average channel length of ground flashes to the average channel length of cloud flashes.

  19. Canonical profiles in tokamaks

    International Nuclear Information System (INIS)

    Dnestrovskij, Yu.N.

    2002-01-01

    We consider the problem of the canonical profiles for tokamak plasma with arbitrary cross-section, taking into account two principles: 1) the free plasma energy minimum with the constraint of total current conservation and 2) the profile consistency. We deduce the Euler differential equation for the canonical profile of μ=1/q with two types of the boundary conditions: soft and stiff. The soft conditions correspond to the Kadomtsev solution for the circular cylinder. The stiff conditions describe a fast response of the plasma over the whole cross-section on the edge impact. Using the canonical profile of the current density, we calculate the critical gradients for the temperature, and create the transport model for the electron and ion temperatures and density. We show that, when the aspect ratio is diminished, or when the elongation increases, the canonical profiles become flatten. The similar tendency for the real profiles of the electron temperature was found in analysis of JET and START experiments. The obtained critical gradients were used to analysis of the experiments in tokamaks with moderate and tight aspect ratios. (author)

  20. Temperature, salinity, oxygen, pressure, and density profiles from CTD casts from chartered fishing boats taken along line off Grays Harbor, WA from 2000-11-15 to 2005-10-20 (NODC Accession 0119769)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This set of CTD profiles are from 10 cruises. These cruises were part of the NOAA sponsored program entitled Olympic Region Harmful Algal Blooms (ORHAB). The aim of...

  1. The probabilistic distribution of metal whisker lengths

    Energy Technology Data Exchange (ETDEWEB)

    Niraula, D., E-mail: Dipesh.Niraula@rockets.utoledo.edu; Karpov, V. G., E-mail: victor.karpov@utoledo.edu [Department of Physics and Astronomy, University of Toledo, Toledo, Ohio 43606 (United States)

    2015-11-28

    Significant reliability concerns in multiple industries are related to metal whiskers, which are random high aspect ratio filaments growing on metal surfaces and causing shorts in electronic packages. We derive a closed form expression for the probabilistic distribution of metal whisker lengths. Our consideration is based on the electrostatic theory of metal whiskers, according to which whisker growth is interrupted when its tip enters a random local “dead region” of a weak electric field. Here, we use the approximation neglecting the possibility of thermally activated escapes from the “dead regions,” which is later justified. We predict a one-parameter distribution with a peak at a length that depends on the metal surface charge density and surface tension. In the intermediate range, it fits well the log-normal distribution used in the experimental studies, although it decays more rapidly in the range of very long whiskers. In addition, our theory quantitatively explains how the typical whisker concentration is much lower than that of surface grains. Finally, it predicts the stop-and-go phenomenon for some of the whiskers growth.

  2. Length of a Hanging Cable

    Directory of Open Access Journals (Sweden)

    Eric Costello

    2011-01-01

    Full Text Available The shape of a cable hanging under its own weight and uniform horizontal tension between two power poles is a catenary. The catenary is a curve which has an equation defined by a hyperbolic cosine function and a scaling factor. The scaling factor for power cables hanging under their own weight is equal to the horizontal tension on the cable divided by the weight of the cable. Both of these values are unknown for this problem. Newton's method was used to approximate the scaling factor and the arc length function to determine the length of the cable. A script was written using the Python programming language in order to quickly perform several iterations of Newton's method to get a good approximation for the scaling factor.

  3. Keeping disease at arm's length

    DEFF Research Database (Denmark)

    Lassen, Aske Juul

    2015-01-01

    and physical activities at the activity centre. In this way, keeping disease at arm’s length is analysed as an ambiguous health strategy. The article shows the importance of looking into how active ageing is practised, as active ageing seems to work well in the everyday life of the older people by not giving......Many older people live with a range of chronic diseases. However, these diseases do not necessarily impede an active lifestyle. In this article the author analyses the relation between the active ageing discourse and the way older people at two Danish activity centres handle disease. How does...... active ageing change everyday life with chronic disease, and how do older people combine an active life with a range of chronic diseases? The participants in the study use activities to keep their diseases at arm’s length, and this distancing of disease at the same time enables them to engage in social...

  4. An Excel™-VBA programme for the analysis of current velocity profiles

    Science.gov (United States)

    Le Roux, J. P.; Brodalka, M.

    2004-10-01

    VPA is an Excel spreadsheet to facilitate the analysis of current velocity profiles and its application to sediment transport studies in steady, uniform, open-channel flows. The program requires input values such as the water temperature (from which the density and dynamic viscosity are calculated), the channel depth and slope, current velocities as measured at different heights above the bed, bedform length and height, as well as the sediment density and median size. The latter can be provided as sieve diameters, fall diameters or as phi values. The velocity profiles are plotted on two graphs, one being a traditional plot of velocity versus height or distance from the bed and the other comparing the observed profile with theoretical profiles for smooth, transitional and rough boundary conditions. VBA macros are provided to clear the spreadsheet before new profiles are analysed, update the formulas, straighten out the velocity profiles, calculate the shear velocity, and save the data on a separate sheet for further analysis. The programme is applied to a new and more accurate method to determine the shear velocity, which can be used to predict the bedload discharge over plane beds and is also incorporated into a dimensionally correct suspended load transport equation combining the parameters most important in sediment transport. A dimensionally correct bedload discharge equation based upon the mean excess flow velocity is also proposed for plane beds, ripples and dunes.

  5. Ion temperature profiles in JET

    International Nuclear Information System (INIS)

    Hellermann, M. von; Mandl, W.; Summers, H.P.; Weisen, H.

    1989-01-01

    The results presented in this paper have shown some extreme cases of ion temperature profiles illustrating the different operation modes of the JET tokamak. In the three examples of low-density high temperature, high-density moderates and high-density high-confinement plasmas comparable values of a maximum fusion product n d T i τ E in the order of 10 20 keV m -3 sec are achieved. (author) 1 ref., 7 figs

  6. Density Development During Erosion Experiments of Cohesive Sediments

    DEFF Research Database (Denmark)

    Johansen, Claus; Larsen, Torben

    1998-01-01

    The density development during erosion experiments was investigated. The calculation of the erosion rate requires the knowledge of the density profile with respect to the consolidation time(Parchure, 1984). At present, the basic assumption in the calculations is that the density profile is achieved...... from consolidation experiments conducted with the same consolidation period (Malta, 1986; Metha and Partheniades, 1979). Furthermore, the density is assumed constant throughout the erosion experiment. Therefore, experiments were conducted in order to investigate this assumption. Kaolinite was used...

  7. Microinstabilities in weak density gradient tokamak systems

    International Nuclear Information System (INIS)

    Tang, W.M.; Rewoldt, G.; Chen, L.

    1986-04-01

    A prominent characteristic of auxiliary-heated tokamak discharges which exhibit improved (''H-mode type'') confinement properties is that their density profiles tend to be much flatter over most of the plasma radius. Depsite this favorable trend, it is emphasized here that, even in the limit of zero density gradient, low-frequency microinstabilities can persist due to the nonzero temperature gradient

  8. Data Profiling

    OpenAIRE

    Hladíková, Radka

    2010-01-01

    Title: Data Profiling Author: Radka Hladíková Department: Department of Software Engineering Supervisor: Ing. Vladimír Kyjonka Supervisor's e-mail address: Abstract: This thesis puts mind on problems with data quality and data profiling. This Work analyses and summarizes problems of data quality, data defects, process of data quality, data quality assessment and data profiling. The main topic is data profiling as a process of researching data available in existing...

  9. Critical length scales for flow phenomena in liquid metal batteries

    Science.gov (United States)

    Kelley, Douglas; Weier, Tom

    2017-11-01

    Liquid metal batteries, a new technology for grid-scale energy storage, are composed of three liquid layers and therefore subject to a wide variety of fluid dynamical phenomena, both beneficial and detrimental. Some, like thermal convection and electrovortex flow, drive finite flow regardless of the size, current density, and temperature of the battery. Others, like the Tayler instability and the metal pad instability, occur only in certain parameter regimes - almost always dependent on length scale. I will discuss critical length scales, considering implications for battery design in light of fundamental fluid dynamics. This work was supported by the National Science Foundation under Award Number CBET-1552182.

  10. Profile constraining mechanism for Te profile invariance in tokamaks

    International Nuclear Information System (INIS)

    Becker, G.

    1993-03-01

    A new model for the electron temperature profile resilience in the outer half of tokamak plasmas is proposed and investigated. It is shown that introducing a negative feedback term into the scaling of the electron heat diffusivity χ e (r) = χ ee (r)(1-αa 2 /T eo d 2 T e /dr 2 ) with α > or ∼ 3 results in the observed T e profile stiffness against variations of the density and heating profiles. In addition, the feedback by itself yields the measured approximately linear T e (r) shape for r/a > or ∼ 0.5 in contrast to previous profile constraining models. (orig.). 6 figs

  11. Karolinske psychodynamic profile (KAPP)

    DEFF Research Database (Denmark)

    Mathiesen, Birgit Bork; Søgaard, Ulf

    2006-01-01

    psykologiske testmetoder, assesment, Karolinska psychodynamic profile (KAPP), psykodynamisk profil......psykologiske testmetoder, assesment, Karolinska psychodynamic profile (KAPP), psykodynamisk profil...

  12. SURVIVAL ANALYSIS AND LENGTH-BIASED SAMPLING

    Directory of Open Access Journals (Sweden)

    Masoud Asgharian

    2010-12-01

    Full Text Available When survival data are colleted as part of a prevalent cohort study, the recruited cases have already experienced their initiating event. These prevalent cases are then followed for a fixed period of time at the end of which the subjects will either have failed or have been censored. When interests lies in estimating the survival distribution, from onset, of subjects with the disease, one must take into account that the survival times of the cases in a prevalent cohort study are left truncated. When it is possible to assume that there has not been any epidemic of the disease over the past period of time that covers the onset times of the subjects, one may assume that the underlying incidence process that generates the initiating event times is a stationary Poisson process. Under such assumption, the survival times of the recruited subjects are called “lengthbiased”. I discuss the challenges one is faced with in analyzing these type of data. To address the theoretical aspects of the work, I present asymptotic results for the NPMLE of the length-biased as well as the unbiased survival distribution. I also discuss estimating the unbiased survival function using only the follow-up time. This addresses the case that the onset times are either unknown or known with uncertainty. Some of our most recent work and open questions will be presented. These include some aspects of analysis of covariates, strong approximation, functional LIL and density estimation under length-biased sampling with right censoring. The results will be illustrated with survival data from patients with dementia, collected as part of the Canadian Study of Health and Aging (CSHA.

  13. Toothbrush probe for instantaneous measurement of radial profile in tokamak boundary plasma

    Energy Technology Data Exchange (ETDEWEB)

    Uehara, Kazuya; Sengoku, Seio [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Amemiya, Hiroshi

    1997-04-01

    A new probe for the instantaneous measurement of radial profiles of the boundary scrape-off layer (SOL) plasma has been developed in a tokamak. Five asymmetric double-probe chips are aligned in parallel to a strong magnetic field in the boundary plasma in a tokamak. This probe is named the `toothbrush probe` and can measure the ion temperature as well as the electron temperature and the plasma density in the SOL plasma within only one tokamak plasma shot. First, only one asymmetric probe is mounted on the divertor plate and it is tried to determine the ion temperature. Then, a manufactured toothbrush probe is mounted in the SOL plasma and the radial plasma profiles are simultaneously obtained. Data on the e-folding length of the plasma profile obtained by the toothbrush probe can determine the information on the transport properties such as the diffusion coefficient and the thermal conductivity of electrons and ions. (author)

  14. Adaptive treatment-length optimization in spatiobiologically integrated radiotherapy

    Science.gov (United States)

    Ajdari, Ali; Ghate, Archis; Kim, Minsun

    2018-04-01

    Recent theoretical research on spatiobiologically integrated radiotherapy has focused on optimization models that adapt fluence-maps to the evolution of tumor state, for example, cell densities, as observed in quantitative functional images acquired over the treatment course. We propose an optimization model that adapts the length of the treatment course as well as the fluence-maps to such imaged tumor state. Specifically, after observing the tumor cell densities at the beginning of a session, the treatment planner solves a group of convex optimization problems to determine an optimal number of remaining treatment sessions, and a corresponding optimal fluence-map for each of these sessions. The objective is to minimize the total number of tumor cells remaining (TNTCR) at the end of this proposed treatment course, subject to upper limits on the biologically effective dose delivered to the organs-at-risk. This fluence-map is administered in future sessions until the next image is available, and then the number of sessions and the fluence-map are re-optimized based on the latest cell density information. We demonstrate via computer simulations on five head-and-neck test cases that such adaptive treatment-length and fluence-map planning reduces the TNTCR and increases the biological effect on the tumor while employing shorter treatment courses, as compared to only adapting fluence-maps and using a pre-determined treatment course length based on one-size-fits-all guidelines.

  15. Step styles of pedestrians at different densities

    Science.gov (United States)

    Wang, Jiayue; Weng, Wenguo; Boltes, Maik; Zhang, Jun; Tordeux, Antoine; Ziemer, Verena

    2018-02-01

    Stepping locomotion is the basis of human movement. The investigation of stepping locomotion and its affecting factors is necessary for a more realistic knowledge of human movement, which is usually referred to as walking with equal step lengths for the right and left leg. To study pedestrians’ stepping locomotion, a set of single-file movement experiments involving 39 participants of the same age walking on a highly curved oval course is conducted. The microscopic characteristics of the pedestrians including 1D Voronoi density, speed, and step length are calculated based on a projected coordinate. The influence of the projection lines with different radii on the measurement of these quantities is investigated. The step lengths from the straight and curved parts are compared using the Kolmogorov–Smirnov test. During the experiments, six different step styles are observed and the proportions of different step styles change with the density. At low density, the main step style is the stable-large step style and the step lengths of one pedestrian are almost constant. At high density, some pedestrians adjust and decrease their step lengths. Some pedestrians take relatively smaller and larger steps alternately to adapt to limited space.

  16. Determining the influence of muscle operating length on muscle performance during frog swimming using a bio-robotic model.

    Science.gov (United States)

    Clemente, Christofer J; Richards, Christopher

    2012-09-01

    Frogs are capable of impressive feats of jumping and swimming. Recent work has shown that anuran hind limb muscles can operate at lengths longer than the 'optimal length'. To address the implications of muscle operating length on muscle power output and swimming mechanics, we built a robotic frog hind limb model based upon Xenopus laevis. The model simulated the force-length and force-velocity properties of vertebrate muscle, within the skeletal environment. We tested three muscle starting lengths, representing long, optimal and short starting lengths. Increasing starting length increased maximum muscle power output by 27% from 98.1 W kg(-1) when muscle begins shortening from the optimal length, to 125.1 W kg(-1) when the muscle begins at longer initial lengths. Therefore, longer starting lengths generated greater hydrodynamic force for extended durations, enabling faster swimming speeds of the robotic frog. These swimming speeds increased from 0.15 m s(-1) at short initial muscle lengths, to 0.39 m s(-1) for the longest initial lengths. Longer starting lengths were able to increase power as the muscle's force-length curve was better synchronized with the muscle's activation profile. We further dissected the underlying components of muscle force, separating force-length versus force-velocity effects, showing a transition from force-length limitations to force-velocity limitations as starting length increased.

  17. Sensing the wind profile

    Energy Technology Data Exchange (ETDEWEB)

    Pena, A.

    2009-03-15

    This thesis consists of two parts. The first is a synopsis of the theoretical progress of the study that is based on a number of journal papers. The papers, which constitute the second part of the report, aim to analyze, measure, and model the wind prole in and beyond the surface layer by combining observations from cup anemometers with lidars. The lidar is necessary to extend the measurements on masts at the Horns Rev offshore wind farm and over at land at Hoevsoere, Denmark. Both sensing techniques show a high degree of agreement for wind speed measurements performed at either sites. The wind speed measurements are averaged for several stability conditions and compare well with the surface-layer wind profile. At Hoevsoere, it is sufficient to scale the wind speed with the surface friction velocity, whereas at Horns Rev a new scaling is added, due to the variant roughness length. This new scaling is coupled to wind prole models derived for flow over the sea and tested against the wind proles up to 160 m at Horns Rev. The models, which account for the boundary-layer height in stable conditions, show better agreement with the measurements than compared to the traditional theory. Mixing-length parameterizations for the neutral wind prole compare well with length-scale measurements up to 300 m at Hoevsoere and 950 m at Leipzig. The mixing-length-derived wind proles strongly deviate from the logarithmic wind prole, but agree better with the wind speed measurements. The length-scale measurements are compared to the length scale derived from a spectral analysis performed up to 160 m at Hoevsoere showing high agreement. Mixing-length parameterizations are corrected to account for stability and used to derive wind prole models. These compared better to wind speed measurements up to 300 m at Hoevsoere than the surface-layer wind prole. The boundary-layer height is derived in nearneutral and stable conditions based on turbulent momentum uxes only and in unstable conditions

  18. Effect of plantation density on kraft pulp production from red pine (Pinus resinosa Ait.)

    Science.gov (United States)

    J.Y. Zhu; G.C. Myers

    2006-01-01

    Red pine (Pinus resinosa Ait.) butt logs from 38 year old research plots were used to study the effect of plantation stand density on kraft pulp production. Results indicate that plantation stand density can affect pulp yield, unrefined pulp mean fibre length, and the response of pulp fibre length to pulp refining. However, the effect of plantation stand density on...

  19. Densidade de estocagem no crescimento, composição e perfil lipídico corporal do jundiá Stocking density in growth, composition and body lipid profile of jundiá

    Directory of Open Access Journals (Sweden)

    Rafael Lazzari

    2011-04-01

    Full Text Available O objetivo do trabalho foi avaliar o crescimento, a composição e o perfil lipídico corporal de jundiás criados em diferentes densidades de estocagem (DE: 4,2; 6,4; 8,6 e 10,8kg m-3 em sistema com recirculação de água. Durante 120 dias, 420 peixes (peso inicial=182,95±2,96g foram alimentados uma vez ao dia, até a saciedade aparente, com dieta peletizada formulada. Observou-se que, quanto maior a DE utilizada, menor é o peso individual dos peixes, entretanto a biomassa por tanque aumentou (PThe aim of this research was to evaluate growth and body composition of jundiá farmed at different stocking densities (SD: 4.2, 6.4, 8.6 and 10.8kg m-3 in a water re-use system. During 120 days, 420 fish were fed near to satiation once a day. It was observed that in the highest SD, the individual fish weight was lower, however the biomass per tank increased (P<0.05. The best feed conversion ratio (1.69 and intraperitoneal fat (3.92% were observed in fish subjected to density of 4.2kg m-3. The body protein was affected by SD. Saturated fatty acids decreased and unsaturated fatty acids increased according to the increase of SD. It was concluded that stocking density influences the final size and yield per volume of jundiá.

  20. String matching with variable length gaps

    DEFF Research Database (Denmark)

    Bille, Philip; Gørtz, Inge Li; Vildhøj, Hjalte Wedel

    2012-01-01

    We consider string matching with variable length gaps. Given a string T and a pattern P consisting of strings separated by variable length gaps (arbitrary strings of length in a specified range), the problem is to find all ending positions of substrings in T that match P. This problem is a basic...

  1. Sensing the wind profile

    DEFF Research Database (Denmark)

    Pena Diaz, Alfredo

    This thesis consists of two parts. The first is a synopsis of the theoretical progress of the study that is based on a number of journal papers. The papers, which constitute the second part of the report, aim to analyze, measure, and model the wind prole in and beyond the surface layer by combining...... measurements are averaged for several stability conditions and compare well with the surface-layer wind profile. At Høvsøre, it is sufficient to scale the wind speed with the surface friction velocity, whereas at Horns Rev a new scaling is added, due to the variant roughness length. This new scaling is coupled...

  2. The influence of tributary flow density differences on the hydrodynamic behavior of a confluent meander bend and implications for flow mixing

    Science.gov (United States)

    Herrero, Horacio S.; Díaz Lozada, José M.; García, Carlos M.; Szupiany, Ricardo N.; Best, Jim; Pagot, Mariana

    2018-03-01

    The goal of this study is to evaluate the influence of tributary flow density differences on hydrodynamics and mixing at a confluent meander bend. A detailed field characterization is performed using an Acoustic Doppler Current Profiler (ADCP) for quantification of the 3D flow field, flow discharge and bathymetry, as well as CTD measurements (conductivity, temperature, depth) to characterize the patterns of mixing. Satellite images of the confluence taken at complementary times to the field surveys were analyzed to evaluate the confluence hydrodynamics at different flow conditions. The results illustrate the differences in hydrodynamics and mixing length in relation to confluences with equal density tributaries. At low-density differences, and higher discharge ratio (Qr) between the two rivers, the flow is similar to equi-density confluent meander bends. In contrast, at high-density differences (low Qr), the tributary flow is confined to near the confluence but the density difference causes the flow to move across channel. In this case, the density difference causes the lateral spread of the tributary flow to be greater than at a greater Qr when the density difference is less. These results illustrate the potential importance of density differences between tributaries in determining the rate and spatial extent of mixing and sediment dispersal at confluent meander bends.

  3. Bond lengths in organic and metal-organic compounds revisited: X-H bond lengths from neutron diffraction data.

    Science.gov (United States)

    Allen, Frank H; Bruno, Ian J

    2010-06-01

    The number of structures in the Cambridge Structural Database (CSD) has increased by an order of magnitude since the preparation of two major compilations of standard bond lengths in mid-1985. It is now of interest to examine whether this huge increase in data availability has implications for the mean bond-length values published in the late 1980s. Those compilations reported mean X-H bond lengths derived from rather sparse information and for rather few chemical environments. During the intervening years, the number of neutron studies has also increased, although only by a factor of around 2.25, permitting a new analysis of X-H bond-length distributions for (a) organic X = C, N, O, B, and (b) a variety of terminal and homometallic bridging transition metal hydrides. New mean values are reported here and are compared with earlier results. These new overall means are also complemented by an analysis of X-H distances at lower temperatures (T chemical environments for which statistically acceptable mean X-H bond lengths can be obtained, although values from individual structures are also collated to further extend the chemical range of this compilation. Updated default 'neutron-normalization' distances for use in hydrogen-bond and deformation-density studies are also proposed for C-H, N-H and O-H, and the low-temperature analysis provides specific values for certain chemical environments and hybridization states of X.

  4. Effects of Three Different Additives and Two Different Bulk Densities on Maize Silage Characteristics, Temperature Profiles, CO2 and O2–Dynamics in Small Scale Silos during Aerobic Exposure

    Directory of Open Access Journals (Sweden)

    Kerstin Helena Jungbluth

    2017-05-01

    Full Text Available Silage quality and aerobic stability are sometimes insufficient. If management requirements are not met, or to improve silage quality, additives are often used. The objective of this study is to investigate the effects of different factors on silage during aerobic conditions. Whole-crop forage maize was harvested and 24 buckets (65 L were filled and assigned to one of four treatment groups: (1 control (no treatment; (2 chemical additive (sodium benzoate, potassium sorbate, sodium acetate; (3 a mixed biological inoculant containing Lactobacillus buchneri, L. plantarum, and Pediococcus acidilacti; and (4 a mixed biological inoculant containing L. buchneri, L. plantarum, and L. rhamnosus. An untreated variation was also ensiled. Two different densities were adjusted during ensiling. After opening, the temperature was measured for seven days and O2 and CO2 concentrations were analysed. The findings show that the chemical additive very effectively prevented silage from reheating and deteriorating. Aerobic reheating of silage was also successfully inhibited through biological additives and high density.

  5. Measurement of vertebral bone marrow lipid profile at 1.5-T proton magnetic resonance spectroscopy and bone mineral density at dual-energy X-ray absorptiometry: correlation in a swine model

    International Nuclear Information System (INIS)

    Di Leo, Giovanni; Fina, Laura; Bandirali, Michele; Messina, Carmelo; Sardanelli, Francesco

    2014-01-01

    Bone marrow is mainly composed of red (hematopoietic) and yellow (fatty) components. Soon after the birth there is a physiological conversion of the bone marrow from red to yellow, so that the percentage of hematopoietic cells and adipocytes changes with aging. Although bone marrow adipogenesis is a physiologic process involving all mammals, recent studies showed an accelerated marrow adipogenesis associated with several chronic conditions, including osteoporosis [4] and diabetes mellitus. Moreover, this increased marrow fat is accompanied by a decrease in bone density. Marrow fat is therefore increasingly believed to influence the bone microenvironment. Diagnostic tools for quantitative measurement of bone marrow fat and bone mineral density (BMD) include proton magnetic resonance spectroscopy (MRS) and dual-energy Xray absorptiometry (DXA), respectively. Using MRS, an inverse relationship between vertebral bone marrow fat content and lumbar BMD has been demonstrated in patients affected with osteoporosis or with diabetes mellitus. In most studies, a quite standard MRS sequence has been used, with short echo times (TE) for the measurement of the bulk methylene. In this study we sought to optimize the MRS sequence in order to try to measure other fat components of the vertebral bone marrow at 1.5 T. For this purpose, we used an animal model that allowed long acquisition times and repeated measures. Moreover, we aimed at estimating in this model the relationship between vertebral bone marrow fat content at proton MRS and BMD at DXA.

  6. Measurement of vertebral bone marrow lipid profile at 1.5-T proton magnetic resonance spectroscopy and bone mineral density at dual-energy X-ray absorptiometry: correlation in a swine model

    Energy Technology Data Exchange (ETDEWEB)

    Di Leo, Giovanni; Fina, Laura [IRCCS Policlinico San Donato, Unita di Radiologia, San Donato Milanese (Italy); Bandirali, Michele; Messina, Carmelo [Universita degli Studi di Milano, Scuola di Specializzazione in Radiodiagnostica, Milan (Italy); Sardanelli, Francesco [IRCCS Policlinico San Donato, Unita di Radiologia, San Donato Milanese (Italy); Universita degli Studi di Milano, Dipartimento di Scienze Biomediche per la Salute, San Donato Milanese (Italy)

    2014-08-15

    Bone marrow is mainly composed of red (hematopoietic) and yellow (fatty) components. Soon after the birth there is a physiological conversion of the bone marrow from red to yellow, so that the percentage of hematopoietic cells and adipocytes changes with aging. Although bone marrow adipogenesis is a physiologic process involving all mammals, recent studies showed an accelerated marrow adipogenesis associated with several chronic conditions, including osteoporosis [4] and diabetes mellitus. Moreover, this increased marrow fat is accompanied by a decrease in bone density. Marrow fat is therefore increasingly believed to influence the bone microenvironment. Diagnostic tools for quantitative measurement of bone marrow fat and bone mineral density (BMD) include proton magnetic resonance spectroscopy (MRS) and dual-energy Xray absorptiometry (DXA), respectively. Using MRS, an inverse relationship between vertebral bone marrow fat content and lumbar BMD has been demonstrated in patients affected with osteoporosis or with diabetes mellitus. In most studies, a quite standard MRS sequence has been used, with short echo times (TE) for the measurement of the bulk methylene. In this study we sought to optimize the MRS sequence in order to try to measure other fat components of the vertebral bone marrow at 1.5 T. For this purpose, we used an animal model that allowed long acquisition times and repeated measures. Moreover, we aimed at estimating in this model the relationship between vertebral bone marrow fat content at proton MRS and BMD at DXA.

  7. Determining the influence of muscle operating length on muscle performance during frog swimming using a bio-robotic model

    International Nuclear Information System (INIS)

    Clemente, Christofer J; Richards, Christopher

    2012-01-01

    Frogs are capable of impressive feats of jumping and swimming. Recent work has shown that anuran hind limb muscles can operate at lengths longer than the ‘optimal length’. To address the implications of muscle operating length on muscle power output and swimming mechanics, we built a robotic frog hind limb model based upon Xenopus laevis. The model simulated the force–length and force–velocity properties of vertebrate muscle, within the skeletal environment. We tested three muscle starting lengths, representing long, optimal and short starting lengths. Increasing starting length increased maximum muscle power output by 27% from 98.1 W kg −1 when muscle begins shortening from the optimal length, to 125.1 W kg −1 when the muscle begins at longer initial lengths. Therefore, longer starting lengths generated greater hydrodynamic force for extended durations, enabling faster swimming speeds of the robotic frog. These swimming speeds increased from 0.15 m s −1 at short initial muscle lengths, to 0.39 m s −1 for the longest initial lengths. Longer starting lengths were able to increase power as the muscle's force–length curve was better synchronized with the muscle's activation profile. We further dissected the underlying components of muscle force, separating force–length versus force–velocity effects, showing a transition from force–length limitations to force–velocity limitations as starting length increased. (paper)

  8. Cephalometric assessment of maxillary length in Serbian children with skeletal class III.

    Science.gov (United States)

    Stojanović, Zdenka; Nikolić, Predrag; Nikodijević, Angelina; Milić, Jasmina; Stojanović, Branislav

    2013-07-01

    Malocclusion of skeletal class III is a complex irregularity of sagittal inter-jaw relationship, which is due to irregularities of sagittal position of one or both of the jaw bones, which is often associated with disproportionate ratio of their length. The aim of this study was to determine whether the length of the jaw of children with skeletal class III in the period of mixed dentition was changed. Fifty children with skeletal class III and the same number of those with skeletal class I, of both sexes, have been selected on the basis of cephalometric analysis of profile tele-x-ray of the head. All the children aged 6-12 had mixed dentition, and were divided according to sex and age into three subgroups within each group. The length of maxilla, mandible and cranial base were measured. Proportions among the lengths measured within each group were found and difference significance in the measured lengths and their proportions among groups and subgroups were evaluated. The children with skeletal class III, compared with the findings in the control group, had significantly lower values of maxillary length, total maxillary length, as well as lower values of their lengths in proportion to lengths of the front or the total length of cranial base and in proportion to mandibular lengths (p children with skeletal class III have significantly shorter maxilla than those with skeletal class I.

  9. Application of Displacement Height and Surface Roughness Length to Determination Boundary Layer Development Length over Stepped Spillway

    Directory of Open Access Journals (Sweden)

    Xiangju Cheng

    2014-12-01

    Full Text Available One of the most uncertain parameters in stepped spillway design is the length (from the crest of boundary layer development. The normal velocity profiles responding to the steps as bed roughness are investigated in the developing non-aerated flow region. A detailed analysis of the logarithmic vertical velocity profiles on stepped spillways is conducted through experimental data to verify the computational code and numerical experiments to expand the data available. To determine development length, the hydraulic roughness and displacement thickness, along with the shear velocity, are needed. This includes determining displacement height d and surface roughness length z0 and the relationship of d and z0 to the step geometry. The results show that the hydraulic roughness height ks is the primary factor on which d and z0 depend. In different step height, step width, discharge and intake Froude number, the relations d/ks = 0.22–0.27, z0/ks = 0.06–0.1 and d/z0 = 2.2–4 result in a good estimate. Using the computational code and numerical experiments, air inception will occur over stepped spillway flow as long as the Bauer-defined boundary layer thickness is between 0.72 and 0.79.

  10. Biophysical Profile

    Science.gov (United States)

    ... and pregnancy High-risk pregnancy Biophysical profile About Advertisement Mayo Clinic does not endorse companies or products. ... a Job Site Map About This Site Twitter Facebook Google YouTube Pinterest Mayo Clinic is a not- ...

  11. Complete Fabrication of a Traversable 3 µm Thick NbN Film Superconducting Coil with Cu plated layer of 42m in Length in a Spiral Three-Storied Trench Engraved in a Si Wafer of 76.2 mm in Diameter Formed by MEMS Technology for a Compact SMES with High Energy Storage Volume Density

    Science.gov (United States)

    Suzuki, Yasuhiro; Iguchi, Nobuhiro; Adachi, Kazuhiro; Ichiki, Akihisa; Hioki, Tatsumi; Hsu, Che-Wei; Sato, Ryoto; Kumagai, Shinya; Sasaki, Minoru; Noh, Joo-Hyong; Sakurahara, Yuuske; Okabe, Kyohei; Takai, Osamu; Honma, Hideo; Watanabe, Hideo; Sakoda, Hitoshi; Sasagawa, Hiroaki; Doy, Hideyuki; Zhou, Shuliang; Hori, H.; Nishikawa, Shigeaki; Nozaki, Toshihiro; Sugimoto, Noriaki; Motohiro, Tomoyoshi

    2017-09-01

    Based on the concept of a novel approach to make a compact SMES unit composed of a stack of Si wafers using MEMS process proposed previously, a complete fabrication of a traversable 3 µam thick NbN film superconducting coil lined with Cu plated layer of 42m in length in a spiral three-storied trench engraved in and extended over a whole Si-wafer of 76.2 mm in diameter was attained for the first time. With decrease in temperature, the DC resistivity showed a metallic decrease indicating the current pass was in the Cu plated layer and then made a sudden fall to residual contact resistance indicating the shift of current pass from the Cu plated layer to the NbN film at the critical temperature Tc of 15.5K by superconducting transition. The temperature dependence of I-V curve showed the increase in the critical current with decrease in the temperature and the highest critical current measured was 220 mA at 4K which is five times as large as that obtained in the test fabrication as the experimental proof of concept presented in the previous report. This completion of a one wafer superconducting NbN coil is an indispensable step for the next proof of concept of fabrication of series-connected two wafer coils via superconductive joint which will read to series connected 600 wafer coils finally, and for replacement of NbN by high Tc superconductor such as YBa2Cu3O7-x for operation under the cold energy of liquid hydrogen or liquid nitrogen.

  12. Profiling cancer

    DEFF Research Database (Denmark)

    Ciro, Marco; Bracken, Adrian P; Helin, Kristian

    2003-01-01

    In the past couple of years, several very exciting studies have demonstrated the enormous power of gene-expression profiling for cancer classification and prediction of patient survival. In addition to promising a more accurate classification of cancer and therefore better treatment of patients......, gene-expression profiling can result in the identification of novel potential targets for cancer therapy and a better understanding of the molecular mechanisms leading to cancer....

  13. Electrostatic stiffening and induced persistence length for coassembled molecular bottlebrushes

    Science.gov (United States)

    Storm, Ingeborg M.; Stuart, Martien A. Cohen; de Vries, Renko; Leermakers, Frans A. M.

    2018-03-01

    A self-consistent field analysis for tunable contributions to the persistence length of isolated semiflexible polymer chains including electrostatically driven coassembled deoxyribonucleic acid (DNA) bottlebrushes is presented. When a chain is charged, i.e., for polyelectrolytes, there is, in addition to an intrinsic rigidity, an electrostatic stiffening effect, because the electric double layer resists bending. For molecular bottlebrushes, there is an induced contribution due to the grafts. We explore cases beyond the classical phantom main-chain approximation and elaborate molecularly more realistic models where the backbone has a finite volume, which is necessary for treating coassembled bottlebrushes. We find that the way in which the linear charge density or the grafting density is regulated is important. Typically, the stiffening effect is reduced when there is freedom for these quantities to adapt to the curvature stresses. Electrostatically driven coassembled bottlebrushes, however, are relatively stiff because the chains have a low tendency to escape from the compressed regions and the electrostatic binding force is largest in the convex part. For coassembled bottlebrushes, the induced persistence length is a nonmonotonic function of the polymer concentration: For low polymer concentrations, the stiffening grows quadratically with coverage; for semidilute polymer concentrations, the brush chains retract and regain their Gaussian size. When doing so, they lose their induced persistence length contribution. Our results correlate well with observed physical characteristics of electrostatically driven coassembled DNA-bioengineered protein-polymer bottlebrushes.

  14. Densities and Excess Molar Volume for the Ternary Systems (1 ...

    African Journals Online (AJOL)

    methylimidazolium methyl sulphate ([BMIM]+[MeSO4]-) were determined. The ternary systems studied were ... The results are interpreted in terms of the alcohol chain length and the intermolecular interactions. KEYWORDS Density, excess molar ...

  15. Density of oxidation-induced stacking faults in damaged silicon

    NARCIS (Netherlands)

    Kuper, F.G.; Hosson, J.Th.M. De; Verwey, J.F.

    1986-01-01

    A model for the relation between density and length of oxidation-induced stacking faults on damaged silicon surfaces is proposed, based on interactions of stacking faults with dislocations and neighboring stacking faults. The model agrees with experiments.

  16. Microinstabilities in weak density gradient tokamak systems

    Energy Technology Data Exchange (ETDEWEB)

    Tang, W.M.; Rewoldt, G.; Chen, L.

    1986-04-01

    A prominent characteristic of auxiliary-heated tokamak discharges which exhibit improved (''H-mode type'') confinement properties is that their density profiles tend to be much flatter over most of the plasma radius. Depsite this favorable trend, it is emphasized here that, even in the limit of zero density gradient, low-frequency microinstabilities can persist due to the nonzero temperature gradient.

  17. Measurements of the plasma density in the FTU tokamak by a pulsed time-of-flight X-wave refractometer

    International Nuclear Information System (INIS)

    Petrov, V. G.; Petrov, A. A.; Malyshev, A. Yu.; De Benedetti, M.; Tudisco, O.

    2008-01-01

    On-line control over the plasma density in tokamaks (especially, in long-term discharges) requires reliable measurements of the averaged plasma density. For this purpose, a new method of density measurements-a pulsed time-of-flight plasma refractometry-was developed and tested in the T-11M tokamak. This method allows one to determine the averaged density from the measured time delay of nanosecond microwave pulses propagating through the plasma. For an O-wave, the measured time delay is proportional to the line-averaged density and is independent of the density profile (f>>f p ) τ o ∼ k o 1/f 2 ∫ l N(x)dx. Here, f is the frequency of the probing wave, f p is the plasma frequency, l= 4 a is the path length for two-pass probing in the equatorial plane, a is the plasma minor radius, k O and k X are numerical factors, f c is the electron-cyclotron frequency at the axis of the plasma column, and f p >>f c , f. Measurements of the time delay provide the same information as plasma interferometry, though they do no employ the effect of interference. When the conditions f p >>f c , f are not satisfied, the measured time delay depends on the shape of the density profile. In this case, in order to determine the average density regardless of the density profile, it is necessary to perform simultaneous measurements at several probing frequencies in order to determine the average density. In ITER (Bt ∼ 5T), a spectral window between the lower and upper cutoff frequencies in the range of 50-100 GHz can be used for pulsed time-of-flight X-wave refractometry. This appreciably simplifies the diagnostics and eliminates the problem of the first mirror. In this paper, the first results obtained in the FTU tokamak with a prototype of the ITER pulsed time-of-flight refractometer are presented. The geometry and layout of experiments similar to the planned ITER experiments are described. The density measured by pulsed time-of-flight refractometry is shown to agree well with the

  18. Development of a longitudinal density monitor for storage rings

    International Nuclear Information System (INIS)

    Zolotorev, M.; Beche, J.-F.; Byrd, J.; Datte, P.; De Santis, S.; Denes, P.; Placidi, M.; Ratti, A.; Riot, V.; Schoenlein, R.; Turner, W.

    2003-01-01

    We report on development of a new storage ring operations tool for measurement of longitudinal beam density profile. The technique mixes synchrotron light with light from a mode locked solid-state laser oscillator in a non-linear crystal and detects the up-converted radiation with a photo-multiplier. The laser is phase locked to the storage ring RF system. The laser choices available for repetition frequency, pulse length and phase modulation give a very wide range of options for matching the bunch configuration of particular storage rings. Progress in the technology of solid-state lasers ensures this system can be made robust for routine use in storage ring operations. A very large number of important applications are possible including measurement of the fraction of untrapped particles prior to acceleration, the population of particles in the nominally unfilled RF buckets in a bunch train (''ghost bunches''), longitudinal tails, the diffusion of particles into the beam abort gap and th e normal bunch parameters of longitudinal shape and intensity. We are currently investigating application to two devices: (1) the 1.9 GeV ALS electron storage ring at LBNL with 328 RF buckets, 2ns bucket spacing, 276 nominally filled bunches, 15-30ps rms bunch length and (2) the 7 TeV LHC proton collider under construction at CERN with 35,640 RF buckets, 2.5 ns bucket spacing, 2,808 nominally filled bunches, 280-620 ps rms bunch length. A proof of principle experiment is being conducted on ALS. The results of the ALS experiment and detailed analyses of the application to LHC and its requirements are described

  19. [Population density of Eucalyptus urophylla plantation].

    Science.gov (United States)

    Huang, B; Lu, C

    2000-02-01

    This paper dealt with the relationships and correlation models of the population density of 5.6 years old Eucalyptus urophylla plantation with its crown width, diamter at breast height(DBH), tree height, individual standing volume, stand volume, wood properties and survital rate. The results showed that the population density remarkably affected DBH, individual standing volume, crown width, live branch height, stand volume and wood fiber width; but not affect tree height, basic density of wood, and length of wood fibers. It had a positive relationship with stand volume, live branch height and wood fibers width, and a negative relationship with DBH, individual standing volume and crown width. In addition, E. urophylla had a wide range of reasonable density. For short-rotation puplwoods, the optimum planting density of E. urophylla is 2000 individuals per hectare.

  20. Analysis of effects of laser profiles on fast electron generation by two-dimensional Particle-In-Cell simulations

    International Nuclear Information System (INIS)

    Hata, M.

    2010-01-01

    Complete text of publication follows. A cone-guided target is used in the Fast Ignition Realization Experiment project phase-I (FIREX-I) and optimization of its design is performed. However a laser profile is not optimized much, because the laser profile that is the best for core heating is not known well. To find that, it is useful to investigate characteristics of generated fast electrons in each condition of different laser profiles. In this research, effects of laser profiles on fast electron generation are investigated on somewhat simple conditions by two-dimensional Particle-In-Cell simulations. In these simulations, a target is made up of Au pre-plasma and Au plasma. The Au pre-plasma has the exponential profile in the x direction with the scale length L = 4.0 μm and the density from 0.10 n cr to 20 n cr . The Au plasma has the flat profile in the x direction with 10 μm width and 20 n cr . Plasma profiles are uniform in the y direction. The ionization degree and the mass number of plasmas are 40 and 197, where the ionization degree is determined by PINOCO simulations. PINOCO is a two-dimensional radiation hydrodynamics simulation code, which simulates formation of the high-density plasma during the compression phase in the fast ignition. A laser is assumed to propagate as plane wave from the negative x direction to the positive x direction. Laser profiles are supposed to be uniform in the y direction. Three different laser profiles, namely flat one with t flat = 100 fs, Gaussian one with t rise/fall = 47.0 fs and flat + Gaussian one with t rise/fall = 23.5 fs and t flat = 50 fs are used. The energy and the peak intensity are constant with E = 10 7 J/cm 2 and I L = 10 20 W/cm 2 in all cases of different laser profiles. We compare results in each condition of three different laser profiles and investigate effects of laser profiles on fast electron generation. Time-integrated energy spectra are similar in all cases of three different laser profiles. In the

  1. Short Rayleigh Length Free Electron Lasers

    CERN Document Server

    Crooker, P P; Armstead, R L; Blau, J

    2004-01-01

    Conventional free electron laser (FEL) oscillators minimize the optical mode volume around the electron beam in the undulator by making the resonator Rayleigh length about one third of the undulator length. This maximizes gain and beam-mode coupling. In compact configurations of high-power infrared FELs or moderate power UV FELs, the resulting optical intensity can damage the resonator mirrors. To increase the spot size and thereby reduce the optical intensity at the mirrors below the damage threshold, a shorter Rayleigh length can be used, but the FEL interaction is significantly altered. A new FEL interaction is described and analyzed with a Rayleigh length that is only one tenth the undulator length, or less. The effect of mirror vibration and positioning are more critical in the short Rayleigh length design, but we find that they are still within normal design tolerances.

  2. Radiographic assessment of endodontic working length

    OpenAIRE

    Osama S Alothmani; Lara T Friedlander; Nicholas P Chandler

    2013-01-01

    The use of radiographs for working length determination is usual practice in endodontics. Exposing radiographs following the principles of the paralleling technique allows more accurate length determination compared to the bisecting-angle method. However, it has been reported that up to 28.5% of cases can have the file tip extending beyond the confines of the root canals despite an acceptable radiographic appearance. The accuracy of radiographic working length determination could be affected ...

  3. Laboratory Density Functionals

    OpenAIRE

    Giraud, B. G.

    2007-01-01

    We compare several definitions of the density of a self-bound system, such as a nucleus, in relation with its center-of-mass zero-point motion. A trivial deconvolution relates the internal density to the density defined in the laboratory frame. This result is useful for the practical definition of density functionals.

  4. Information, polarization and term length in democracy

    DEFF Research Database (Denmark)

    Schultz, Christian

    2008-01-01

    accountable, but the re-election incentive leads to policy-distortion as the government seeks to manipulate swing voters' beliefs to make its ideology more popular. This creates a trade-off: A short term length improves accountability but gives distortions. A short term length is best for swing voters when......This paper considers term lengths in a representative democracy where the political issue divides the population on the left-right scale. Parties are ideologically different and better informed about the consequences of policies than voters are. A short term length makes the government more...

  5. Electronic structure and electron momentum density in TiSi

    Energy Technology Data Exchange (ETDEWEB)

    Ghaleb, A.M. [Department of Physics, College of Science, University of Kirkuk, Kirkuk (Iraq); Mohammad, F.M. [Department of Physics, College of Science, University of Tikreet, Tikreet (Iraq); Sahariya, Jagrati [Department of Physics, University College of Science, M.L. Sukhadia University, Udaipur 313001, Rajasthan (India); Sharma, Mukesh [Physics Division, Forensic Science Laboratory, Jaipur, Rajasthan (India); Ahuja, B.L., E-mail: blahuja@yahoo.com [Department of Physics, University College of Science, M.L. Sukhadia University, Udaipur 313001, Rajasthan (India)

    2013-03-01

    We report the electron momentum density in titanium monosilicide using {sup 241}Am Compton spectrometer. Experimental Compton profile has been compared with the theoretical profiles computed using linear combination of atomic orbitals (LCAO). The energy bands, density of states and Fermi surface structures of TiSi are reported using the LCAO and the full potential linearized augmented plane wave methods. Theoretical anisotropies in directional Compton profiles are interpreted in terms of energy bands. To confirm the conducting behavior, we also report the real space analysis of experimental Compton profile of TiSi.

  6. Electronic structure and electron momentum density in TiSi

    International Nuclear Information System (INIS)

    Ghaleb, A.M.; Mohammad, F.M.; Sahariya, Jagrati; Sharma, Mukesh; Ahuja, B.L.

    2013-01-01

    We report the electron momentum density in titanium monosilicide using 241 Am Compton spectrometer. Experimental Compton profile has been compared with the theoretical profiles computed using linear combination of atomic orbitals (LCAO). The energy bands, density of states and Fermi surface structures of TiSi are reported using the LCAO and the full potential linearized augmented plane wave methods. Theoretical anisotropies in directional Compton profiles are interpreted in terms of energy bands. To confirm the conducting behavior, we also report the real space analysis of experimental Compton profile of TiSi

  7. In situ spatiotemporal mapping of flow fields around seeded stem cells at the subcellular length scale.

    Directory of Open Access Journals (Sweden)

    Min Jae Song

    2010-09-01

    Full Text Available A major hurdle to understanding and exploiting interactions between the stem cell and its environment is the lack of a tool for precise delivery of mechanical cues concomitant to observing sub-cellular adaptation of structure. These studies demonstrate the use of microscale particle image velocimetry (μ-PIV for in situ spatiotemporal mapping of flow fields around mesenchymal stem cells, i.e. murine embryonic multipotent cell line C3H10T1/2, at the subcellular length scale, providing a tool for real time observation and analysis of stem cell adaptation to the prevailing mechanical milieu. In the absence of cells, computational fluid dynamics (CFD predicts flow regimes within 12% of μ-PIV measures, achieving the technical specifications of the chamber and the flow rates necessary to deliver target shear stresses at a particular height from the base of the flow chamber. However, our μ-PIV studies show that the presence of cells per se as well as the density at which cells are seeded significantly influences local flow fields. Furthermore, for any given cell or cell seeding density, flow regimes vary significantly along the vertical profile of the cell. Hence, the mechanical milieu of the stem cell exposed to shape changing shear stresses, induced by fluid drag, varies with respect to proximity of surrounding cells as well as with respect to apical height. The current study addresses a previously unmet need to predict and observe both flow regimes as well as mechanoadaptation of cells in flow chambers designed to deliver precisely controlled mechanical signals to live cells. An understanding of interactions and adaptation in response to forces at the interface between the surface of the cell and its immediate local environment may be key for de novo engineering of functional tissues from stem cell templates as well as for unraveling the mechanisms underlying multiscale development, growth and adaptation of organisms.

  8. Solar corona electron density distribution

    International Nuclear Information System (INIS)

    Esposito, P.B.; Edenhofer, P.; Lueneburg, E.

    1980-01-01

    Three and one-half months of single-frequency (f= 0 2.2 x 10 9 Hz) time delay data (earth-to-spacecraft and return signal travel time) were acquired from the Helios 2 spacecraft around the time of its solar occupation (May 16, 1976). Following the determination of the spacecraft trajectory the excess time delay due to the integrated effect of free electrons along the signal's ray path could be separated and modeled. An average solar corona, equatorial, electron density profile, during solar minimum, was deduced from time delay measurements acquired within 5--60 solar radii (R/sub S/) of the sun. As a point of reference, at 10 R/sub S/ from the sun we find an average electron density of 4500 el cm -3 . However, there appears to be an asymmtry in the electron density as the ray path moved from the west (preoccultation) to east (post-occulation) solar limb. This may be related to the fact that during entry into occulation the heliographic latitude of the ray path (at closes approach to the sun) was about 6 0 , whereas during exit it became -7 0 . The Helios electron density model is compared with similar models deduced from a variety of different experimental techniques. Within 5--20 R/sub S/ of the sun the models separate according to solar minimum or maximum conditions; however, anomalies are evident

  9. Plasma profile recovery by function parameterisation

    International Nuclear Information System (INIS)

    McCarthy, P.J.; Sexton, M.C.

    1986-11-01

    The use of Function Parameterisation for the recovery of plasma profiles as a function of flux surface area from spatial point data directly combined with external magnetic measurements is demonstrated in the case of ASDEX electron temperature and density profiles. The extrapolated temperature on the magnetic axis is shown to be more reliable than that obtained from a conventional fitting procedure. (orig.)

  10. Density and surface tension of ionic liquids.

    Science.gov (United States)

    Kolbeck, C; Lehmann, J; Lovelock, K R J; Cremer, T; Paape, N; Wasserscheid, P; Fröba, A P; Maier, F; Steinrück, H-P

    2010-12-30

    We measured the density and surface tension of 9 bis[(trifluoromethyl)sulfonyl]imide ([Tf(2)N](-))-based and 12 1-methyl-3-octylimidazolium ([C(8)C(1)Im](+))-based ionic liquids (ILs) with the vibrating tube and the pendant drop method, respectively. This comprehensive set of ILs was chosen to probe the influence of the cations and anions on density and surface tension. When the alkyl chain length in the [C(n)C(1)Im][Tf(2)N] series (n = 1, 2, 4, 6, 8, 10, 12) is increased, a decrease in density is observed. The surface tension initially also decreases but reaches a plateau for alkyl chain lengths greater than n = 8. Functionalizing the alkyl chains with ethylene glycol groups results in a higher density as well as a higher surface tension. For the dependence of density and surface tension on the chemical nature of the anion, relations are only found for subgroups of the studied ILs. Density and surface tension values are discussed with respect to intermolecular interactions and surface composition as determined by angle-resolved X-ray photoelectron spectroscopy (ARXPS). The absence of nonvolatile surface-active contaminants was proven by ARXPS.

  11. Fellow Profile

    Indian Academy of Sciences (India)

    Home; Fellowship. Fellow Profile. Elected: 1977 Section: Animal Sciences. Nair, Prof. Narayana Balakrishnan Ph.D and D.Sc. (Madras), D.Sc. (h.c.), FNA, FNASc, FNAAS, FTWAS. Date of birth: 6 July 1927. Date of death: 21 April 2010. Specialization: Aquatic Biology & Fisheries and Ecology Last known address: Swathi, ...

  12. Fellow Profile

    Indian Academy of Sciences (India)

    Fellow Profile. Elected: 1977 Section: Animal Sciences. Nair, Prof. Narayana Balakrishnan Ph.D and D.Sc. (Madras), D.Sc. (h.c.), FNA, FNASc, FNAAS, FTWAS. Date of birth: 6 July 1927. Date of death: 21 April 2010. Specialization: Aquatic Biology & Fisheries and Ecology Last known address: Swathi, Residency Road, ...

  13. Fellow Profile

    Indian Academy of Sciences (India)

    Fellow Profile. Elected: 1974 Section: Earth & Planetary Sciences. Koteswaram, Prof. Pancheti D.Sc. (Madras), FNA. Date of birth: 25 March 1915. Date of death: 11 January 1997. Specialization: Atmospheric Physics Meteorology and Hydrology Last known address: 'Varsha', 8-1-11, University Road, Waltair Uplands, ...

  14. Fellow Profile

    Indian Academy of Sciences (India)

    Fellow Profile. Elected: 1957 Section: Earth & Planetary Sciences. Rao, Mr Mandagere Bharadwaj Ramachandra M.Sc. (Mysore). Date of birth: 5 August 1906. Date of death: 4 September 1992. Specialization: Geology and Exploration Geophysics Last known address: 669, Third Block, Rajajinagar, Bengaluru 560 010.

  15. 7 CFR 29.3037 - Length.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Length. 29.3037 Section 29.3037 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing.... Length, as an element of quality, does not apply to tobacco in strip form. (See Elements of quality.) [24...

  16. 7 CFR 29.6024 - Length.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Length. 29.6024 Section 29.6024 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... INSPECTION Standards Definitions § 29.6024 Length. The linear measurement of cured tobacco leaves from the...

  17. Local gauge invariant QED with fundamental length

    International Nuclear Information System (INIS)

    Kadyshevsky, V.G.; Mateev, M.D.

    1981-01-01

    A local gauge theory of electromagnetic interactions with the fundamental length l as a new universal scale is worked out. The Lagrangian contains new extra terms in which the coupling constant is proportional to the fundamental length. The theory has an elegant geometrical basis: in momentum representation one faces de Sitter momentum space with curvature radius 1/l [ru

  18. Analysis of ureteral length in adult cadavers

    Directory of Open Access Journals (Sweden)

    Hugo F. F. Novaes

    2013-04-01

    Full Text Available Introduction In some occasions, correlations between human structures can help planning surgical intra-abdominal interventions. The previous determination of ureteral length helps pre-operatory planning of surgeries, reduces costs of auxiliary exams, the correct choice of double-J catheter with low morbidity and fewer symptoms, and an adequate adhesion to treatment. Objective To evaluate ureteral length in adult cadavers and to analyze its correlation with anthropometric measures. Materials and Methods: From April 2009 to January 2012 we determined ureteral length of adult cadavers submitted to necropsy and obtained the following measures: height, distance from shoulder to wrist, elbow-wrist, xiphoid appendix-umbilicus, umbilicus-pubis, xiphoid appendix-pubis and between iliac spines. We analyzed the correlations between ureteral length and those anthropometric measures. Results We dissected 115 ureters from 115 adult corpses from April 2009 to January 2012. Median ureteral length didn't vary between sexes or according to height. It was observed no correlation among ureteral length and all considered anthropometric measures in all analyzed subgroups and in general population. There were no significant differences between right and left ureteral measures. Conclusions There is no difference of ureteral length in relation to height or gender (male or female. There is no significant correlation among ureteral length and the considered anthropometric measures.

  19. The length of the male urethra

    Directory of Open Access Journals (Sweden)

    Tobias. S. Kohler

    2008-08-01

    Full Text Available PURPOSE: Catheter-based medical devices are an important component of the urologic armamentarium. To our knowledge, there is no population-based data regarding normal male urethral length. We evaluated the length of the urethra in men with normal genitourinary anatomy undergoing either Foley catheter removal or standard cystoscopy. MATERIALS AND METHODS: Male urethral length was obtained in 109 men. After study permission was obtained, the subject's penis was placed on a gentle stretch and the catheter was marked at the tip of the penis. The catheter was then removed and the distance from the mark to the beginning of the re-inflated balloon was measured. Alternatively, urethral length was measured at the time of cystoscopy, on removal of the cystoscope. Data on age, weight, and height was obtained in patients when possible. RESULTS: The mean urethral length was 22.3 cm with a standard deviation of 2.4 cm. Urethral length varied between 15 cm and 29 cm. No statistically significant correlation was found between urethral length and height, weight, body mass index (BMI, or age. CONCLUSIONS: Literature documenting the length of the normal male adult urethra is scarce. Our data adds to basic anatomic information of the male urethra and may be used to optimize genitourinary device design.

  20. On the homology length spectrum of surfaces

    OpenAIRE

    Massart, Daniel; Parlier, Hugo

    2014-01-01

    On a surface with a Finsler metric, we investigate the asymptotic growth of the number of closed geodesics of length less than L which minimize length among all geodesic multicurves in the same homology class. An important class of surfaces which are of interest to us are hyperbolic surfaces.