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Sample records for apparent molal volumes

  1. Study of apparent molal volume and viscosity of mutual citric acid and disodium hydrogen orthophosphate aqueous systems

    Indian Academy of Sciences (India)

    Man Singh

    2006-05-01

    Fundamental properties, density () and viscosity (), of citric acid (CA) and disodium hydrogen orthophosphate (DSP) at various strengths were obtained at different temperatures. The and values were used to determine apparent molal volumes and viscosity of systems. The , and values were regressed against molality for ρ0, 0 and $V^{0}_{\\phi}$f, the limiting constants at infinite dilution ( → 0) forionic and molecular interactions. The ρ0 and $V^{0}_{\\phi}$f of aq. acids are higher than those of aq. DSP and the viscosity of DSP is higher than that of aq. CA. Examination of ρ0 and $V^{0}_{\\phi}$ functions indicates that mutual compositions of CA and DSP counterbalance concentration and temperature effects on pH in bioprocesses.

  2. Thermodynamics of the first and second proton dissociations from aqueous L-aspartic acid and L-glutamic acid at temperatures from (278.15 to 393.15) K and at the pressure 0.35 MPa: Apparent molar heat capacities and apparent molar volumes of zwitterionic, protonated cationic, and deprotonated anionic forms at molalities from (0.002 to 1.0) mol . kg{sup -1}

    Energy Technology Data Exchange (ETDEWEB)

    Ziemer, S.P. [Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT 84602-5700 (United States); Woolley, E.M. [Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT 84602-5700 (United States)]. E-mail: earl_woolley@byu.edu

    2007-04-15

    We have measured the densities of aqueous solutions of L-aspartic acid, L-glutamic acid, and equimolal solutions of these two amino acids with HCl and with NaOH at temperatures 278.15 {<=} T/K {<=} 368.15, at molalities 0.002 {<=} m/mol . kg{sup -1} {<=} 1.0 as solubity of the solutes allowed, and at p = 0.35 MPa using a vibrating tube densimeter. We have also measured the heat capacities of these solutions at 278.15 {<=} T/K {<=} 393.15 and at the same m and p using a twin fixed-cell differential temperature-scanning calorimeter. We used the densities to calculate apparent molar volumes V {sub {phi}} and the heat capacities to calculate apparent molar heat capacities C {sub p,{phi}} for these solutions. We used our results and values from the literature for V {sub {phi}}(T, m) and C {sub p,{phi}}(T, m) for HCl(aq), NaOH(aq), and NaCl(aq) and the molar heat capacity change {delta}{sub r} C {sub p,m}(T, m) for ionization of water to calculate parameters for {delta}{sub r} C {sub p,m}(T, m) for the first two proton dissociations from each of the protonated aqueous cationic amino acids. We used Young's Rule and integrated these results iteratively to account for the effects of equilibrium speciation and chemical relaxation on V {sub {phi}}(T, m) and C {sub p,{phi}}(T, m). This procedure gave parameters for V {sub {phi}}(T, m) and C {sub p,{phi}}(T, m) for L-aspartinium and L-glutaminium chlorides and for monosodium L-aspartate and L-glutamate which modeled our observed results within experimental uncertainties. We report values for {delta}{sub r} C {sub p,m}, {delta}{sub r} H {sub m}, pQ {sub a}, {delta}{sub r} S {sub m}, and {delta}{sub r} V {sub m} for the first and second proton dissociations from protonated aqueous L-aspartic acid and L-glutamic acid as functions of T and m.

  3. Thermodynamics on the Molality Scale

    Science.gov (United States)

    Canagaratna, Sebastian G.; Maheswaran, M.

    2013-01-01

    For physical measurements, the compositions of solutions, especially electrolyte solutions, are expressed in terms of molality rather than mole fractions. The development of the necessary thermodynamic equations directly in terms of molality is not common in textbooks, and the treatment in the literature is not very systematic. We develop a…

  4. Group additivity equations of state for calculating the standard molal thermodynamic properties of aqueous organic species at elevated temperatures and pressures

    Science.gov (United States)

    Amend, Jan P.; Helgeson, Harold C.

    1997-01-01

    Group additivity equations of state for aqueous organic molecules have been generated by combining the revised Helgeson-Kirkham-Flowers (HKF) equations of state ( Shock and Helgeson, 1988, 1990; Tanger and Helgeson, 1988; Shock et al., 1989, 1992) with experimental values of the standard molal properties of aqueous alkanes, alkanols, alkylbenzenes, car☐ylic acids, amides, and amines. Equations of state parameters for the groups represented by -CH 2-, -CH 3, -CHCH 3-, -C 6H 5, -CH 2OH, -COOH, -CONH 2, and -CH 2NH 2 were determined by regression of the experimental data. This procedure permits calculation of the standard molal thermodynamic properties of these groups at elevated temperatures and pressures. Although curves representing the apparent standard molal Gibbs free energies (Δ G°) and enthalpies (Δ H°) of formation, and the standard molal entropies ( S°) of the groups as a function of temperature and pressure are respectively similar for each of them, the temperature dependence of the standard molal heat capacities ( Cp°) and volumes ( V°) of a number of the groups are quite different from one another. For example, the standard molal heat capacities of the hydrocarbon groups minimize with increasing temperature, but those of -CH 2OH and -CH 2NH 2 maximize. Computed values of Δ G°, Δ H°, S°, Cp°, V°, and the equations of state parameters for the various groups were used together with group additivity relations to generate corresponding values of these properties for aqueous n-alkanes, 2-methylalkanes, n-alkylbenzenes, n-alkanols, n-car☐ylic acids, n-amides, and n-amines at temperatures ≤ 250°C and pressures ≤ 1 kbar. The validity and generality of the equations of state are supported by the fact that predicted equilibrium constants for liquid n-alkane solubility reactions in water compare favorably with experimental values reported in the literature for temperatures as high as 200°C. Furthermore, equilibrium constants for aqueous ethane

  5. Apparent and partial molar volumes of long-chain alkyldimethylbenzylammonium chlorides and bromides in aqueous solutions at T=15 deg. C and T=25 deg. C[Alkyldimethylbenzylammonium chlorides; Alkyldimethylbenzylammonium bromides; Micellization; Density; Apparent molar volumes

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Perez, A.; Ruso, J.M.; Nimo, J.; Rodriguez, J.R. E-mail: fmjulio@usc.es

    2003-12-01

    Density measurements of dodecyl- (C{sub 12}DBACl), tetradecyl- (C{sub 14}DBACl), hexadecyldimethylbenzylammonium chloride (C{sub 16}DBACl) and of decyl- (C{sub 10}DBABr) and dodecyldimethylbenzylammonium bromide (C{sub 12}DBABr) in aqueous solutions at T=15 deg. C and T=25 deg. C have been carried out. From these results, apparent and partial molar volumes were calculated. Positive deviations from the Debye-Hueckel limiting law provide evidence for limited association at concentrations below the critical micelle concentration. The change of the apparent molar volume upon micellization was calculated. The relevant parameters have been presented in function of the alkyl chain length. Apparent molar volumes of the present compounds in the micellar phase, V{sub phi}{sup m}, and the change upon micellization, {delta}V{sub phi}{sup m}, have been discussed in terms of temperature and type of counterion.

  6. The effect of drop volume and micropillar shape on the apparent contact angle of ordered microstructured surfaces.

    Science.gov (United States)

    Afferrante, Luciano; Carbone, Giuseppe

    2014-06-14

    In the present paper, we propose a new theoretical approach to evaluate the shape and apparent contact angle (ACA) of a drop gently deposited on microstructured superhydrophobic surfaces. We exploit the very large separation of scales between the drop size and the features of the micromorphology of the interface to propose a numerical methodology to calculate the apparent contact area and apparent contact angle. In agreement with very recent experiments, calculations show that, in the case of surfaces made of conical micropillars, the ACA may take values very close to 180° not depending on the size of the liquid drop. At large drop volumes, the shape of the drop deviates from the spherical one as a result of the gravity effects, but it is noteworthy that the apparent contact angle does not change at all. Our calculations shows that this holds true also for different pillar shapes, showing that, for any given Young contact angle of the solid constituting the pillars, the ACA is an intrinsic property of the surface microgeometry.

  7. DENSITY, REFRACTIVE INDEX, APPARENT VOLUMES AND EXCESS MOLAR VOLUMES OF FOUR PROTIC IONIC LIQUIDS + WATER AT T=298.15 AND 323.15 K

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    R. Rocha Pinto

    2015-09-01

    Full Text Available AbstractDensities and refractive index of binay mixtures of water with four protic ionic liquids, based on ammonium and fatty acids, were measured at 298.15 and 323.15 K, under atmospheric pressure. Apparent and excess molar volumes were obtained by experiments and fitting data to the Redlich-Meyer (RM, Redlich-Kister (RK and Prigogine-Flory-Patterson (PFP equations. The molar volume values were high, suggesting strong ion-solvent interaction. The same interaction also became stronger as the temperature increased. Excess volume values were negative, indicating that packing efficiency ability or attractive interactions occurred in mixtures of ionic liquid + water. The errors (AARD for the properties in excess were in the range of 1.8% to 7.2%. The PFP error for the apparent volume was in the range of 0.34% to 0.06%, lower than the RM error for the same property, which was in the range of 0.70 to 1.55%. The Gladstone-Dale model was applied to correlate the refractive index of the binary mixture with the density from the values of both pure components.

  8. Prediction of subacute infarct lesion volumes by processing apparent diffusion coefficient maps based on apparent diffusion coefficient cut-off values in patients with acute stroke

    Institute of Scientific and Technical Information of China (English)

    郭翔

    2014-01-01

    Objective To explore the feasibility of prediction of subacute infarct lesion volumes by processing ADC maps based on ADC cut-off values in patients with acute stroke.Methods MRI was performed in 20 patients with clinically diagnosed acute infarct less than 6 h after stroke onset.The MRI included a DWI and conventional MRI.The follow-up MR examinations of all the patients

  9. Calculation of the Standard Molal Thermodynamic Properties of Crystalline, Liquid, and Gas Organic Molecules at High Temperatures and Pressures

    Science.gov (United States)

    Helgeson, Harold C.; Owens, Christine E.; Knox, Annette M.; Richard, Laurent

    1998-03-01

    Calculation of the thermodynamic properties of organic solids, liquids, and gases at high temperatures and pressures is a requisite for characterizing hydrothermal metastable equilibrium states involving these species and quantifying the chemical affinities of irreversible reactions of organic molecules in natural gas, crude oil, kerogen, and coal with minerals and organic, inorganic, and biomolecular aqueous species in interstitial waters in sedimentary basins. To facilitate calculations of this kind, coefficients for the Parameters From Group Contributions (PFGC) equation of state have been compiled for a variety of groups in organic liquids and gases. In addition, molecular weights, critical temperatures and pressures, densities at 25°C and 1 bar, transition, melting, and boiling temperatures ( Tt,Pr, Tm,Pr, and Tv,Pr, respectively) and standard molal enthalpies of transition (Δ H° t,Pr), melting (Δ H° m,Pr), and vaporization (Δ H° v,Pr) of organic species at 1 bar ( Pr) have been tabulated, together with an internally consistent and comprehensive set of standard molal Gibbs free energies and enthalpies of formation from the elements in their stable state at 298.15 K ( Tr) and Pr (Δ G° f and Δ H° f, respectively). The critical compilation also includes standard molal entropies ( S°) and volumes ( V°) at Tr and Pr, and standard molal heat capacity power function coefficients to compute the standard molal thermodynamic properties of organic solids, liquids, and gases as a function of temperature at 1 bar. These properties and coefficients have been tabulated for more than 500 crystalline solids, liquids, and gases, and those for many more can be computed from the equations of state group additivity algorithms. The crystalline species correspond to normal alkanes (C nH 2( n+1) ) with carbon numbers ( n, which is equal to the number of moles of carbon atoms in one mole of the species) ranging from 5 to 100, and 23 amino acids including glycine (C 2H 5NO

  10. Estimating the apparent culm volume for Bambusa oldhamii and Bambusa vulgaris = Estimação do volume aparente de colmos de Bambusa oldhamii e Bambusa vulgaris.

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    Carlos Roberto Sanquetta

    2015-06-01

    Full Text Available There is great potential in Brazil for the cultivation of indigenous and introduced species of bamboo. However, there is little scientific research on the biometric aspects of these plants, and this may limit their management and use. The aim of this article therefore, is to present options for estimating the total apparent volume of two species of the genus Bambusa: B. oldhami i and B. vulgaris, planted in an experiment set up in December of 2008 in Pinhais, in the state of Paraná, Brazil (PR. Twenty-four stems were cubed at 50 months using the Smalian method. Diameter at breast height (DAP ranged from 1.8 to 4.5 cm, and height from 3 to 7 m. The options being tested for estimating the apparent volume of the culms were: 1 Schumacher-Hall conventional volume model; 2 fifth-degree polynomial taper model; 3 fractional-power polynomial taper model; and 4 form factor. The options were examined statistically relative to the observed values for the target variable, for each species and for both species as a set. It was found that the four options give precise estimates. There was no statistical difference between the four approaches and the control (observed values by paired t-test. The residuals (estimated x observed values are shown to be homoscedastic with a maximum width of from -30 to 30%. It was concluded that the four methods under test can be used to estimate the target variable under the conditions of the experimental material. The Schumacher-Hall model represents the best compromise between simplicity and accuracy = O Brasil possui grande potencial de cultivo de espécies autóctones e introduzidas de bambu. Contudo, são poucos os trabalhos científicos que versam sobre aspectos biométricos dessas plantas, o que pode representar uma limitação para seu manejo e utilização. Assim, objetivou-se com esse artigo apresentar opções para estimativa do volume total aparente de duas espécies do gênero Bambusa: B. oldhamii e B. vulgaris

  11. Temperature, pressure, and electrochemical constraints on protein speciation: Group additivity calculation of the standard molal thermodynamic properties of ionized unfolded proteins

    Directory of Open Access Journals (Sweden)

    J. M. Dick

    2006-01-01

    Full Text Available Thermodynamic calculations can be used to quantify environmental constraints on the speciation of proteins, such as the pH and temperature dependence of ionization state, and the relative chemical stabilities of proteins in different biogeochemical settings. These calculations depend in part on values of the standard molal Gibbs energies of proteins and their ionization reactions as a function of temperature and pressure. Because these values are not generally available, we calculated values of the standard molal thermodynamic properties at 25°C and 1 bar as well as the revised Helgeson-Kirkham-Flowers equations of state parameters of neutral and charged zwitterionic reference model compounds including aqueous amino acids, polypeptides, and unfolded proteins. The experimental calorimetric and volumetric data for these species taken from the literature were combined with group additivity algorithms to calculate the properties and parameters of neutral and ionized sidechain and backbone groups in unfolded proteins. The resulting set of group contributions enables the calculation of the standard molal Gibbs energy, enthalpy, entropy, isobaric heat capacity, volume, and isothermal compressibility of unfolded proteins in a range of proton ionization states to temperatures and pressures exceeding 100°C and 1000 bar. This approach provides a useful frame of reference for thermodynamic studies of protein folding and complexation reactions. It can also be used to assign provisional values of the net charge and Gibbs energy of ionized proteins as a function of temperature and pH. Using these values, an Eh-pH diagram for a reaction representing the speciation of extracellular proteins from Pyrococcus furiosus and Bacillus subtilis was generated. The predicted predominance limits of these proteins correspond with the different electrochemical conditions of hydrothermal vents and soils. More comprehensive calculations of this kind may reveal pervasive

  12. Temperature, pressure, and electrochemical constraints on protein speciation: Group additivity calculation of the standard molal thermodynamic properties of ionized unfolded proteins

    Science.gov (United States)

    Dick, J. M.; Larowe, D. E.; Helgeson, H. C.

    2006-07-01

    Thermodynamic calculations can be used to quantify environmental constraints on the speciation of proteins, such as the pH and temperature dependence of ionization state, and the relative chemical stabilities of proteins in different biogeochemical settings. These calculations depend in part on values of the standard molal Gibbs energies of proteins and their ionization reactions as a function of temperature and pressure. Because these values are not generally available, we calculated values of the standard molal thermodynamic properties at 25°C and 1 bar as well as the revised Helgeson-Kirkham-Flowers equations of state parameters of neutral and charged zwitterionic reference model compounds including aqueous amino acids, polypeptides, and unfolded proteins. The experimental calorimetric and volumetric data for these species taken from the literature were combined with group additivity algorithms to calculate the properties and parameters of neutral and ionized sidechain and backbone groups in unfolded proteins. The resulting set of group contributions enables the calculation of the standard molal Gibbs energy, enthalpy, entropy, isobaric heat capacity, volume, and isothermal compressibility of unfolded proteins in a range of proton ionization states to temperatures and pressures exceeding 100°C and 1000 bar. This approach provides a useful frame of reference for thermodynamic studies of protein folding and complexation reactions. It can also be used to assign provisional values of the net charge and Gibbs energy of ionized proteins as a function of temperature and pH. Using these values, an Eh-pH diagram for a reaction representing the speciation of extracellular proteins from Pyrococcus furiosus and Bacillus subtilis was generated. The predicted predominance limits of these proteins correspond with the different electrochemical conditions of hydrothermal vents and soils. More comprehensive calculations of this kind may reveal pervasive chemical potential

  13. Group additivity calculation of the standard molal thermodynamic properties of aqueous amino acids, polypeptides and unfolded proteins as a function of temperature, pressure and ionization state

    Science.gov (United States)

    Dick, J. M.; Larowe, D. E.; Helgeson, H. C.

    2005-10-01

    Thermodynamic calculation of the chemical speciation of proteins and the limits of protein metastability affords a quantitative understanding of the biogeochemical constraints on the distribution of proteins within and among different organisms and chemical environments. These calculations depend on accurate determination of the ionization states and standard molal Gibbs free energies of proteins as a function of temperature and pressure, which are not generally available. Hence, to aid predictions of the standard molal thermodynamic properties of ionized proteins as a function of temperature and pressure, calculated values are given below of the standard molal thermodynamic properties at 25°C and 1 bar and the revised Helgeson-Kirkham-Flowers equations of state parameters of the structural groups comprising amino acids, polypeptides and unfolded proteins. Group additivity and correlation algorithms were used to calculate contributions by ionized and neutral sidechain and backbone groups to the standard molal Gibbs free energy (Δ G°), enthalpy (Δ H°), entropy (S°), isobaric heat capacity (C°P), volume (V°) and isothermal compressibility (κ°T) of multiple reference model compounds. Experimental values of C°P, V° and κ°T at high temperature were taken from the recent literature, which ensures an internally consistent revision of the thermodynamic properties and equations of state parameters of the sidechain and backbone groups of proteins, as well as organic groups. As a result, Δ G°, Δ H°, S° C°P, V° and κ°T of unfolded proteins in any ionization state can be calculated up to T~-300°C and P~-5000 bars. In addition, the ionization states of unfolded proteins as a function of not only pH, but also temperature and pressure can be calculated by taking account of the degree of ionization of the sidechain and backbone groups present in the sequence. Calculations of this kind represent a first step in the prediction of chemical affinities of many

  14. Group additivity calculation of the standard molal thermodynamic properties of aqueous amino acids, polypeptides and unfolded proteins as a function of temperature, pressure and ionization state

    Directory of Open Access Journals (Sweden)

    J. M. Dick

    2005-10-01

    Full Text Available Thermodynamic calculation of the chemical speciation of proteins and the limits of protein metastability affords a quantitative understanding of the biogeochemical constraints on the distribution of proteins within and among different organisms and chemical environments. These calculations depend on accurate determination of the ionization states and standard molal Gibbs free energies of proteins as a function of temperature and pressure, which are not generally available. Hence, to aid predictions of the standard molal thermodynamic properties of ionized proteins as a function of temperature and pressure, calculated values are given below of the standard molal thermodynamic properties at 25°C and 1 bar and the revised Helgeson-Kirkham-Flowers equations of state parameters of the structural groups comprising amino acids, polypeptides and unfolded proteins. Group additivity and correlation algorithms were used to calculate contributions by ionized and neutral sidechain and backbone groups to the standard molal Gibbs free energy (Δ G°, enthalpy (Δ H°, entropy (S°, isobaric heat capacity (C°P, volume (V° and isothermal compressibility (κ°T of multiple reference model compounds. Experimental values of C°P, V° and κ°T at high temperature were taken from the recent literature, which ensures an internally consistent revision of the thermodynamic properties and equations of state parameters of the sidechain and backbone groups of proteins, as well as organic groups. As a result, Δ G°, Δ H°, S° C°P, V° and κ°T of unfolded proteins in any ionization state can be calculated up to T~-300°C and P~-5000 bars. In addition, the ionization states of unfolded proteins as a function of not only pH, but also temperature and pressure can be calculated by taking account of the degree of ionization of the sidechain and backbone groups present in the sequence. Calculations of this

  15. Molal Enthalpy of Solution of Ionic Liquid [C2mim][GaCl4

    Institute of Scientific and Technical Information of China (English)

    GUAN,Wei; LIU,Li; WANG,Caixia; YANG,Jiazhen

    2009-01-01

    An ionic liquid (IL),[C2mim][GaCl4](l-ethyl-3-methylimidazolium chlorogallate),was prepared by directly mixing 1-ethyl-3-methylimidazolium chloride ([C2mim][Cl]) and anhydrous GaCI3 with a molar ratio of 1/1 under dry argon.The molal enthalpies of solution,△sHm,of [C2mim][GaCl4],were measured over a molality range of about 0.008-0.1 mol·kg 1 by a solution reaction isoperibol calorimeter at 298.15 K.Considering the hydrolization of anion [GaCl4]- in dissolution process of the IL,a new method of determining the standard molal enthalpy of solution,△sH(⊙)m,was put forward on the basis of Pitzer's mixed electrolyte solution theory so that △sH(⊙)m = -132kJ·mol-1 and the sum of Pitzer's parameters;4β(0)GaCl + 4β(0)[C2mim].Cl + ΦGa,[C2mim]= -0.1373076,β(1)LGa,Cl + β(1)L[C2mim].C=0.3484209 were obtained.In terms of thermodynamic cycle and Glasser's theory of lattice energy for IL,the dissociation enthalpy of [GaCl4]-(g),△Hdis([GaCl4]-)≈5855 kJ·mol-1,that is enthalpy change for the reaction:[GaCl4]-(g)→Ga3+(g) +4Cl- (g),was estimated.

  16. Hyperpolarized 3He apparent diffusion coefficient MRI of the lung: reproducibility and volume dependency in healthy volunteers and patients with emphysema

    DEFF Research Database (Denmark)

    Diaz, S.; Casselbrant, I.; Piitulainen, E.;

    2008-01-01

    PURPOSE: To measure the apparent diffusion coefficient (ADC) of hyperpolarized (HP) (3)He gas using diffusion weighted MRI in healthy volunteers and patients with emphysema and examine the reproducibility and volume dependency. MATERIALS AND METHODS: A total of eight healthy volunteers and 16...... days was good in both healthy volunteers and patients (SD range of 0.003-0.013 cm(2)/second and 0.001-0.009 cm(2)/second at 6% and 15% of TLC for healthy volunteers, and a SD range of 0.001-0.041 cm(2)/second and 0.001-0.011 cm(2)/second, respectively, for patients). A minor but significant increase...... in mean ADC with increased inhaled gas volume was observed in both groups. CONCLUSION: Mean ADC and SD of HP (3)He MRI is reproducible and discriminates well between healthy controls and patients with emphysema at the higher gas volume. This method is robust and may be useful to gain new insights...

  17. Investigation of techniques to quantify in vivo lesion volume based on comparison of water apparent diffusion coefficient (ADC) maps with histology in focal cerebral ischemia of rats.

    Science.gov (United States)

    Kazemi, Mark; Silva, Matthew D; Li, Fuhai; Fisher, Marc; Sotak, Christopher H

    2004-06-01

    Stroke lesion-volume estimates derived from calculated water apparent diffusion coefficient (ADC) maps provide a quantitative surrogate end-point for investigating the efficacy of drug treatment or studying the temporal evolution of cerebral ischemia. Methodology is described for estimating ischemic lesion volumes in a rat model of permanent middle cerebral artery occlusion (MCAO) based on absolute and percent-reduction threshold values of the water ADC at 3 h post-MCAO. Volume estimates derived from average ADC (ADC(av)) maps were compared with those derived from post-mortem histological sections. Optimum ADC thresholds were established as those that provided the best correlation and one-to-one correspondence between ADC- and histologically derived lesion-volume estimates. At 3 h post-MCAO, an absolute-ADC(av) threshold of 47 x 10(-5) mm(2)/s (corresponding to a 33% reduction in ADC(av) based on a contralateral hemisphere comparison) provided the most accurate estimate of percent hemispheric lesion volume (%HLV). Experimental and data analysis issues for improving and validating the usefulness of DWI as a surrogate endpoint for the quantification of ischemic lesion volume are discussed.

  18. Apparent molar volumes and viscosity B-coefficients of caffeine in aqueous thorium nitrate solutions at T = (298.15, 308.15, and 318.15) K

    Energy Technology Data Exchange (ETDEWEB)

    Sinha, Biswajit, E-mail: biswachem@gmail.co [Department of Chemistry, University of North Bengal, Darjeeling 734013 (India); Roy, Pran Kumar; Sarkar, Bipul Kumar; Brahman, Dhiraj [Department of Chemistry, University of North Bengal, Darjeeling 734013 (India); Roy, Mahendra Nath, E-mail: mahendraroy2002@yahoo.co.i [Department of Chemistry, University of North Bengal, Darjeeling 734013 (India)

    2010-03-15

    Apparent molar volumes phi{sub V} and viscosity B-coefficients for caffeine in (0.00, 0.03, 0.05, and 0.07) mol . dm{sup -3} aqueous thorium nitrate, Th(NO{sub 3}){sub 4}, solutions were determined from solution density and viscosity measurements over the temperature range (298.15 to 318.15) K as function of concentration of caffeine and the relation: phi{sub V}{sup 0}=a{sub 0}+a{sub 1}T+a{sub 2}T{sup 2}, have been used to describe the temperature dependence of the standard partial molar volumes phi{sub V}{sup 0}. These results have been used to deduce the standard volumes of transfer DELTAphi{sub V}{sup 0} and viscosity B-coefficients of transfer DELTAB for caffeine from water to aqueous Th(NO{sub 3}){sub 4} solutions for rationalizing various interactions in the ternary solutions. The structure-making or breaking ability of caffeine has been discussed in terms of the sign of (delta{sup 2}phi{sub V}{sup 0}/deltaT{sup 2}){sub P}. The Friedman-Krishnan co-sphere model was used to explain the transfer volume of caffeine with increasing Th(NO{sub 3}){sub 4} molarity. The activation parameters of viscous flow for the ternary solutions were also discussed in terms of transition state theory.

  19. Nuclear magnetic resonance (NMR) measurement of the apparent diffusion coefficient (ADC) of tissue water and its relationship to cell volume changes in pathological states.

    Science.gov (United States)

    Sotak, Christopher H

    2004-09-01

    Diffusion-weighted nuclear magnetic resonance (NMR) imaging (DWI) is sensitive to the random translational motion of water molecules due to Brownian motion. Although the mechanism is still not completely understood, the cellular swelling that accompanies cell membrane depolarization results in a reduction in the net displacement of diffusing water molecules and thus a concomitant reduction in the apparent diffusion coefficient (ADC) of tissue water. Cerebral regions of reduced ADC appear hyperintense in a DWI and this technique has been used extensively to study acute stroke. In addition to cerebral ischemia, reductions in the ADC of cerebral water have been observed following cortical spreading depression, ischemic depolarizations (IDs), transient ischemic attack (TIA), status epilepticus, and hypoglycemia. Although the mechanism responsible for initiating membrane depolarization varies in each case, the ensuing cell volume changes follow a similar pattern. Water ADC values are also affected by the presence and orientation of barriers to translational motion (such as cell membranes and myelin fibers) and thus NMR measures of anisotropic diffusion are sensitive to more chronic pathological states where the integrity of these structures is modified by disease. Both theoretical prediction and experimental evidence suggest that the ADC of tissue water is related to the volume fraction of the interstitial space via the electrical conductivity of the tissue. The implication is that acute neurological disorders that exhibit electrical conductivity changes should also exhibit ADC changes that are detectable by DWI. A qualitative correlation between electrical conductivity and the ADC of water has been demonstrated in a number of animal model studies and the results indicate that reduced ADC values are associated with reductions in the extracellular volume fraction and increased extracellular tortuosity. The close relationship between ADC changes and cell volume changes in

  20. Excess Molar Volume and Apparent Molar Volume of Binary Mixtures of 2—Methyl—3—buten—2—ol with 1—Alcohol at 298.15K

    Institute of Scientific and Technical Information of China (English)

    LIUDixia; LIHaoran; 等

    2002-01-01

    Excess molar volumes (VmE) of binary mixtures of 2-methyl-3-buten-2-ol[CH3C(OH)(CH3)CHCH2] with four 1-alcohols:methanol,ethanol,1-propanol and 1-butanol at 298.15K and atmospheric pressure are derived from density measurements with a vibrating-tube densimeter.All the excess volumes are negative in the systems over the entire composition range. The results are correlated with the Redlich-Kister equation.The effects of chain length of 1-alcohols on VmE are discussed.The apparent molar volumes of 2-methyl-3-buten-2-ol and 1-alcohols are calculated respectively.

  1. Assessment of treatment response by total tumor volume and global apparent diffusion coefficient using diffusion-weighted MRI in patients with metastatic bone disease: a feasibility study.

    Directory of Open Access Journals (Sweden)

    Matthew D Blackledge

    Full Text Available We describe our semi-automatic segmentation of whole-body diffusion-weighted MRI (WBDWI using a Markov random field (MRF model to derive tumor total diffusion volume (tDV and associated global apparent diffusion coefficient (gADC; and demonstrate the feasibility of using these indices for assessing tumor burden and response to treatment in patients with bone metastases. WBDWI was performed on eleven patients diagnosed with bone metastases from breast and prostate cancers before and after anti-cancer therapies. Semi-automatic segmentation incorporating a MRF model was performed in all patients below the C4 vertebra by an experienced radiologist with over eight years of clinical experience in body DWI. Changes in tDV and gADC distributions were compared with overall response determined by all imaging, tumor markers and clinical findings at serial follow up. The segmentation technique was possible in all patients although erroneous volumes of interest were generated in one patient because of poor fat suppression in the pelvis, requiring manual correction. Responding patients showed a larger increase in gADC (median change = +0.18, range = -0.07 to +0.78 × 10(-3 mm2/s after treatment compared to non-responding patients (median change = -0.02, range = -0.10 to +0.05 × 10(-3 mm2/s, p = 0.05, Mann-Whitney test, whereas non-responding patients showed a significantly larger increase in tDV (median change = +26%, range = +3 to +284% compared to responding patients (median change = -50%, range = -85 to +27%, p = 0.02, Mann-Whitney test. Semi-automatic segmentation of WBDWI is feasible for metastatic bone disease in this pilot cohort of 11 patients, and could be used to quantify tumor total diffusion volume and median global ADC for assessing response to treatment.

  2. Partial molar volume of paracetamol in water, 0.1 M HCl and 0.154 M NaCl at T = (298.15, 303.15, 308.15 and 310.65) K and at 101.325 kPa

    Energy Technology Data Exchange (ETDEWEB)

    Iqbal, Muhammad Javed [Department of Chemistry, Quaid-i-Azam University, Islamabad, Capital 54320 (Pakistan)]. E-mail: mjiqauchem@yahoo.com; Malik, Qaisar Mahmood [Department of Chemistry, Quaid-i-Azam University, Islamabad, Capital 54320 (Pakistan)]. E-mail: qaisar_@hotmail.com

    2005-12-15

    The apparent molar volume of paracetamol (4-acetamidophenol) in water, 0.1 M HCl and 0.154 M NaCl as solvents at (298.15, 303.15, 308.15 and 310.65) K temperatures and at a pressure of 101.325 kPa were determined from the density data obtained with the help of a vibrating-tube Anton Paar DMA-48 densimeter. The partial molar volume, V {sub m}, of paracetamol in these solvents at different temperatures was evaluated by extrapolating the apparent molar volume versus molality plots to m = 0. In addition, the partial molar expansivity, E {sup .}, the isobaric coefficient of thermal expansion, {alpha} {sub p}, and the interaction coefficient, S {sub v}, have also been computed. The expansivity data show dependence of E {sup .} values on the structure of the solute molecules.

  3. True progression versus pseudoprogression in the treatment of glioblastomas: A comparison study of normalized cerebral blood volume and apparent diffusion coefficient by histogram analysis

    Energy Technology Data Exchange (ETDEWEB)

    Song, Yong Sub; Choi, Seung Hong; Park, Chul Kee [Seoul National University College of Medicine, Seoul (Korea, Republic of); and others

    2013-08-15

    The purpose of this study was to differentiate true progression from pseudoprogression of glioblastomas treated with concurrent chemoradiotherapy (CCRT) with temozolomide (TMZ) by using histogram analysis of apparent diffusion coefficient (ADC) and normalized cerebral blood volume (nCBV) maps. Twenty patients with histopathologically proven glioblastoma who had received CCRT with TMZ underwent perfusion-weighted imaging and diffusion-weighted imaging (b = 0, 1000 sec/mm{sup 2}). The corresponding nCBV and ADC maps for the newly visible, entirely enhancing lesions were calculated after the completion of CCRT with TMZ. Two observers independently measured the histogram parameters of the nCBV and ADC maps. The histogram parameters between the true progression group (n = 10) and the pseudoprogression group (n = 10) were compared by use of an unpaired Student's t test and subsequent multivariable stepwise logistic regression analysis to determine the best predictors for the differential diagnosis between the two groups. Receiver operating characteristic analysis was employed to determine the best cutoff values for the histogram parameters that proved to be significant predictors for differentiating true progression from pseudoprogression. Intraclass correlation coefficient was used to determine the level of inter-observer reliability for the histogram parameters. The 5th percentile value (C5) of the cumulative ADC histograms was a significant predictor for the differential diagnosis between true progression and pseudoprogression (p 0.044 for observer 1; p = 0.011 for observer 2). Optimal cutoff values of 892 x 10{sup -6} mm{sup 2}/sec for observer 1 and 907 x 10{sup -6} mm{sup 2}/sec for observer 2 could help differentiate between the two groups with a sensitivity of 90% and 80%, respectively, a specificity of 90% and 80%, respectively, and an area under the curve of 0.880 and 0.840, respectively. There was no other significant differentiating parameter on the n

  4. Why size matters: differences in brain volume account for apparent sex differences in callosal anatomy: the sexual dimorphism of the corpus callosum.

    Science.gov (United States)

    Luders, Eileen; Toga, Arthur W; Thompson, Paul M

    2014-01-01

    Numerous studies have demonstrated a sexual dimorphism of the human corpus callosum. However, the question remains if sex differences in brain size, which typically is larger in men than in women, or biological sex per se account for the apparent sex differences in callosal morphology. Comparing callosal dimensions between men and women matched for overall brain size may clarify the true contribution of biological sex, as any observed group difference should indicate pure sex effects. We thus examined callosal morphology in 24 male and 24 female brains carefully matched for overall size. In addition, we selected 24 extremely large male brains and 24 extremely small female brains to explore if observed sex effects might vary depending on the degree to which male and female groups differed in brain size. Using the individual T1-weighted brain images (n=96), we delineated the corpus callosum at midline and applied a well-validated surface-based mesh-modeling approach to compare callosal thickness at 100 equidistant points between groups determined by brain size and sex. The corpus callosum was always thicker in men than in women. However, this callosal sex difference was strongly determined by the cerebral sex difference overall. That is, the larger the discrepancy in brain size between men and women, the more pronounced the sex difference in callosal thickness, with hardly any callosal differences remaining between brain-size matched men and women. Altogether, these findings suggest that individual differences in brain size account for apparent sex differences in the anatomy of the corpus callosum.

  5. Apparent molar volume and modeling of volumetric properties of ionic liquid aqueous solutions 1-butyl-3-metilmidazolium chloride [Bmim+][Cl-] at various temperatures

    Directory of Open Access Journals (Sweden)

    Manuel Páez-Meza

    2014-01-01

    Full Text Available Se determinaron las densidades de las soluciones acuosas del líquido iónico Cloruro 1-butil-3 metilmidazolio [Bmim+][Cl-] utilizando un densímetro de tubo vibrador Anton Paar DMA 5000 entre 283,15 y 218,15 K. Se calcularon y ajustaron los volúmenes molares aparentes VVφφ del cloruro de 1-butil-3-metilimidazolio acuoso al modelo de interacción iónica de Pitzer y se obtuvieron los volúmenes molares aparentes (0VV (1VV 0 VV límites VVφφ y los parámetros volumétricos de Pitzer ββ MMMM , ββ MMMM , CC MMMM a las temperaturas de (283.15, 288.15, 293.15, 298.15, 303.15, 313.15 y 318.15K; comprobándose que este modelo representa adecuadamente los datos volumétricos experimentales por debajo de una fuerza iónica de 0,6018 mol/kg. Finalmente a partir del volumen molar aparente límite determinado a varias temperaturas, se calcularon las expansibilidades molares aparentes límites φφ 0 y los resultados se discutieron en términos de las interacciones que ocurren en solución. EE.

  6. Subtleties in the calculation of the pressure and pressure tensor of anisotropic particles from volume-perturbation methods and the apparent asymmetry of the compressive and expansive contributions

    Science.gov (United States)

    Brumby, Paul E.; Haslam, Andrew J.; de Miguel, Enrique; Jackson, George

    2011-01-01

    An efficient and versatile method to calculate the components of the pressure tensor for hard-body fluids of generic shape from the perspective of molecular simulation is presented. After due consideration of all the possible repulsive contributions exerted by molecules upon their surroundings during an anisotropic system expansion, it is observed that such a volume change can, for non-spherical molecules, give rise to configurations where overlaps occur. This feature of anisotropic molecules has to be taken into account rigorously as it can lead to discrepancies in the calculation of tensorial contributions to the pressure. Using the condition of detailed balance as a basis, a perturbation method developed for spherical molecules has been extended so that it is applicable to non-spherical and non-convex molecules. From a series of 'ghost' anisotropic volume perturbations the residual contribution to the components of the pressure tensor may be accurately calculated. Comparisons are made with prior methods and, where relevant, results are evaluated against existing data. For inhomogeneous systems this method provides a particularly convenient route to the calculation of the interfacial tension (surface free energy) from molecular simulations.

  7. Measurement and COrrelation on Viscosity and Apparent Molar Volume of Ternary System for L—ascorbic Acid in Aqueous D—Glucose and Sucrose Solutions

    Institute of Scientific and Technical Information of China (English)

    赵长伟; 马沛生

    2003-01-01

    Visosities and densities at ,several temperatures from 293.15 K to 313.15K are reported for L-ascorbic acid in aqueous glucose and sucrose solutions at different concentrations.The parameters of density,Viscosity coefficient B and partial molar volume are calculated by regression.The experimental results show that densities and viscositis decrease as temperature increases at the same solute and solvent (glucose and sucrose aueous solution)concentrations,and increase with concentration of glucose and sucrose at the same solute concentration and temperature,B increases with concentration of glucose and sucrose and temaperature,L-ascorbic acid is sturcture-breaker or structure-making for the glucose and sucrose aqueous solutions ,Furthermore,the solute-solvent interactions in ternary systems of water-glucose-electrolyte and water-sucrose-electrolyte are discussed.

  8. Thermodynamic Phase And Chemical Equilibrium At 0-110 C For The H+-K+-Na+-Cl--H2O System Up To 16 Molal And The HNO3-H2O System Up To 20 Molal Using An Association-Based Pitzer Model Compatible With ASPEN Plus

    Energy Technology Data Exchange (ETDEWEB)

    Nichols,T.T.; Taylor,D.D.

    2003-09-26

    A status is presented of the parameterization during FY2003 of an association-based Pitzer model to simulate chemical and phase equilibria of acid-chloride-nitrate-mercury aqueous electrolyte systems at 0-100 C within the industry-standard process simulator, ASPEN Plus. Compatibility with ASPEN Plus requires that the Pitzer model used be limited to the third virial coefficient and have the values of b and a1 as originally proposed by Pitzer. Two aqueous models for 0-110 C at atmospheric pressure were parameterized in FY03. The model for the aqueous H+-K+-Na+-Cl- system is applicable for 0-16 molal, and the HNO3-H2O for 0-20 molal. An association-based Pitzer activity coefficient model is combined with Henry's law to predict activity/osmotic coefficient and VLE. The chloride model also predicts KCl and NaCl solubility, while the nitric acid model has the unique capability of predicting extent of dissociation with an average absolute deviation of 1.43%. The association-based approach presented here extends the utility of the molality-based Pitzer model past 6 molal to predict activity/osmotic coefficients up to 16-20 molal. The association-based approach offers the additional benefits of predicting extent of dissociation and of allowing the Pitzer model to be fully utilized in commercial simulators, such as ASPEN Plus, that require accounting for association to implement Henry's law. The Pitzer models presented here provide the chemical process simulation engineer with a superior alternative to the Electrolyte NRTL model that can easily be used in ASPEN Plus.

  9. Thermodynamic Phase And Chemical Equilibrium At 0-110°C For The H+-K+-Na+-Cl--H2O System Up To 16 Molal And The HNO3-H2O System Up To 20 Molal Using An Association-Based Pitzer Model Compatible With ASPEN Plus

    Energy Technology Data Exchange (ETDEWEB)

    Todd T. Nichols; Dean D. Taylor

    2003-09-01

    A status is presented of the parameterization during FY2003 of an association-based Pitzer model to simulate chemical and phase equilibria of acid-chloride-nitrate-mercury aqueous electrolyte systems at 0-100° C within the industry-standard process simulator, ASPEN Plus. Compatibility with ASPEN Plus requires that the Pitzer model used be limited to the third virial coefficient and have the values of b and a1 as originally proposed by Pitzer. Two aqueous models for 0-110° C at atmospheric pressure were parameterized in FY03. The model for the aqueous H+-K+-Na+-Cl- system is applicable for 0-16 molal, and the HNO3-H2O for 0-20 molal. An association-based Pitzer activity coefficient model is combined with Henry.s law to predict activity/osmotic coefficient and VLE. The chloride model also predicts KCl and NaCl solubility, while the nitric acid model has the unique capability of predicting extent of dissociation with an average absolute deviation of 1.43%. The association-based approach presented here extends the utility of the molality-based Pitzer model past 6 molal to predict activity/osmotic coefficients up to 16-20 molal. The association-based approach offers the additional benefits of predicting extent of dissociation and of allowing the Pitzer model to be fully utilized in commercial simulators, such as ASPEN Plus, that require accounting for association to implement Henry’s law. The Pitzer models presented here provide the chemical process simulation engineer with a superior alternative to the Electrolyte NRTL model that can easily be used in ASPEN Plus.

  10. Apparent Bicarbonate Space in Children

    Directory of Open Access Journals (Sweden)

    Horacio A. Repetto

    2006-01-01

    Full Text Available The amount needed to change the concentration of a solute requires the knowledge of its volume of distribution in the solution. Electrolytes that do not participate in active metabolic reactions have a fixed volume of distribution that corresponds to the volume of water in which they solubilize. Bicarbonate infusion is used to correct hyperchloremic metabolic acidosis. Its volume of distribution (bicarbonate space changes with its participation in the blood buffer systems. In other words, it is not a fixed physical volume, like that of other solutes. In this paper, we shall review experimental studies that supported evidence for this knowledge and analyze the basic hypothesis to explain the phenomena. Since we have not found clinical studies in children, we shall report our experience in a group of patients with metabolic acidosis treated with bicarbonate infusion in whom apparent bicarbonate space was measured and compared with data in adults from the literature. Guidelines for amount of bicarbonate needed to increase its concentration according to baseline bicarbonate concentration will be suggested.

  11. Volúmenes molales parciales de transferencia de algunas sulfonamidas desde el agua hasta la mezcla agua-etanol (X = 0.5)

    OpenAIRE

    2002-01-01

    A partir de valores de densidad de soluciones de diferentes concentraciones, determinados a 25,00 °C, se calcularon los volúmenes molales parciales de transferencia a dilución infinita de algunas sulfonamidas estructuralmente relacionadas, como especies moleculares y como sales sódicas, desde el agua hasta la mezcla agua-etanol de composición 0.5 en fracción molar; adicionalmente se calcularon los volúmenes de los grupos sustituyentes. Los resultados se discuten en términos de interacciones e...

  12. The apparent Universe

    Science.gov (United States)

    Binétruy, P.; Helou, A.

    2015-10-01

    We exploit the parallel between dynamical black holes and cosmological spacetimes to describe the evolution of Friedmann-Lemaître-Robertson-Walker universes from the point of view of an observer in terms of the dynamics of the apparent horizon. Using the Hayward-Kodama formalism of dynamical black holes, we clarify the role of the Clausius relation to derive the Friedmann equations for a Universe, in the spirit of Jacobson’s work on the thermodynamics of spacetime. We also show how dynamics at the horizon naturally leads to the quantum-mechanical process of Hawking radiation. We comment on the connection of this work with recent ideas to consider our observable Universe as a Bose-Einstein condensate and on the corresponding role of vacuum energy.

  13. 2-甲基-3-丁烯-2-醇+直链一元醇二元体系的过量摩尔体积和表观摩尔体积298.15 K)%Excess Molar Volume and Apparent Molar Volume of Binary Mixtures of 2-Methyl-3-buten-2-ol with 1-Alcohol at 298.15 K

    Institute of Scientific and Technical Information of China (English)

    刘迪霞; 李浩然; 邓东顺; 韩世钧

    2002-01-01

    Excess molar volumes (VEm) of binary mixtures of 2-methyl-3-buten-2-ol [CH3C(OH)(CH3)CHCH2]with four 1-alcohols: methanol, ethanol, 1-propanol and 1-butanol at 298.15 K and atmospheric pressure are derived from density measurements with a vibrating-tube densimeter. All the excess volumes are negative in the systems over the entire composition range. The results are correlated with the Redlich-Kister equation. The effects of chain length of 1-alcohols on VmE are discussed. The apparent molar volumes of 2-methyl-3-buten-2-ol and 1-alcohols are calculated respectively.

  14. Effects of structural isomerism on solution behaviour of solutes: Apparent molar volumes and isentropic compression of catechol, resorcinal, and hydroquinone in aqueous solution at T = (283.15, 293.15, 298.15, 303.15, and 313.15) K

    Energy Technology Data Exchange (ETDEWEB)

    Bayram, Edip [Department of Chemistry, Akdeniz University, Antalya 07058 (Turkey); Ayranci, Erol, E-mail: eayranci@akdeniz.edu.t [Department of Chemistry, Akdeniz University, Antalya 07058 (Turkey)

    2010-09-15

    Effects of structural isomerism on solution behaviour of dihydroxybenzenes were examined through the determination of volumetric properties such as apparent molar volumes, apparent molar isentropic compressions, and isobaric expansions. The isomers were 1,2-dihydroxybenzene (catechol), 1,3-dihydroxybenzene (resorcinol), and 1,4-dihydroxybenzene (hydroquinone). The volumetric properties were determined from accurate density and speed of sound measurements at T = (283.15, 293.15, 298.15, 303.15, and 313.15) K and at various concentrations. Values at infinite dilution of these parameters were obtained by suitable extrapolation procedures. The results are discussed in terms of hydrophobic, hydrogen bonding, and dipole-dipole interactions between the three isomers and water. Catechol was found to have the strongest hydrophilic and the weakest hydrophobic interactions with water among the three isomers.

  15. Apparent Clustering and Apparent Background Earthquakes Biased by Undetected Seismicity

    CERN Document Server

    Sornette, D

    2005-01-01

    In models of triggered seismicity and in their inversion with empirical data, the detection threshold m_d is commonly equated to the magnitude m_0 of the smallest triggering earthquake. This unjustified assumption neglects the possibility of shocks below the detection threshold triggering observable events. We introduce a formalism that distinguishes between the detection threshold m_d and the minimum triggering earthquake m_0 < m_d. By considering the branching structure of one complete cascade of triggered events, we derive the apparent branching ratio n_a (which is the apparent fraction of aftershocks in a given catalog) and the apparent background source S_a that are observed when only the structure above the detection threshold m_d is known due to the presence of smaller undetected events that are capable of triggering larger events. If earthquake triggering is controlled in large part by the smallest magnitudes as several recent analyses have shown, this implies that previous estimates of the cluster...

  16. Thermodynamics of the apparent horizon in massive cosmology

    CERN Document Server

    Li, Hui

    2013-01-01

    Applying Clausius relation with energy-supply defined by the unified first law of thermodynamics formalism to the apparent horizon of a massive cosmological model proposed lately, the corrected entropic formula of the apparent horizon is obtained with the help of the modified Friedmann equations. This entropy-area relation, together with the identified internal energy, verifies the first law of thermodynamics for the apparent horizon with a volume change term for consistency. On the other hand, by means of the corrected entropy-area formula and the Clausius relation $\\delta Q=T dS$, where the heat flow $\\delta Q$ is the energy-supply of pure matter projecting on the vector $\\xi$ tangent to the apparent horizon and should be looked on as the amount of energy crossing the apparent horizon during the time interval $dt$ and the temperature of the apparent horizon for energy crossing during the same interval is $1/(2\\pi \\widetilde{r}_A)$, the modified Friedmann equations governing the dynamical evolution of the un...

  17. Radiation chemical effects in the near-field environment of a radwaste repository: {gamma} radiolysis in 6 molal NaCl solutions; Strahlenchemische Effekte im Endlagernahbereich: {gamma}-Radiolyse in 6 molarer NaCl-Loesung

    Energy Technology Data Exchange (ETDEWEB)

    Kelm, M.; Bohnert, E.

    1997-12-01

    The radiation emitted from high-level radioactive wastes in a radwaste repository causes radiolysis products to be formed in brines resulting from water intrusion. The products may alter via redox and complexing reactions the mobilisation processes of radionuclides. The major products of {gamma} radiolysis determined in 6 molal NaCl solution as a function of radiation dose are hydrogen, oxygen, and chlorate. Hypochlorite and chlorite were found to have concentrations in the {mu}Mol/kg range. There was no dependence on dose rate. For the experiments under atmospheric pressure, which allowed radiolytic gas to escape from the solution, the G values measured are 0.46 (H{sub 2}), 0.16 (O{sub 2}), and 0.074 (ClO{sub 3}). In pressurized experiments, with radiolytic gas remaining contained in the solution, the radiolytic effect was much smaller. After approx. 100 days, at a dose of about 2 MGy, gas equilibrium concentrations of some mMol/kg were measured. The results can be qualitatively described by a system of parallel running reaction rate equations. As to quantitative analysis, the reaction model needs to be refined. (orig./CB) [Deutsch] Die Strahlung von hochradioaktiven Abfaellen in einem Endlager im Salz hat zur Folge, dass bei einem Wasserzutritt in den entstehenden Laugen Radiolyseprodukte gebildet werden. Die Radiolyseprodukte koennen durch Redox- und Komplexierungsreaktionen die Mobilisierbarkeit von Radionukliden veraendern. Als Hauptprodukte der {gamma}-Radiolyse wurden in 6 molaler NaCl-Loesung Wasserstoff, Sauerstoff und Chlorat in Abhaengigkeit von der Dosis bestimmt. Hypochlorit und Chlorit erreichten nur Konzentrationen im {mu}Mol/kg-Bereich. Eine Dosisleistungsabhaengigkeit war nicht festzustellen. Bei den Experimenten unter Normaldruck, bei denen die Radiolysegase aus der Loesung entweichen konnten, betrugen die G-Werte 0.46 (H{sub 2}), 0,16 (O{sub 2}) und 0,074 (ClO{sub 3}{sup -}). Bei den Experimenten unter Druck wurden die Radiolysegase in Loesung

  18. Distribution of apparent stress in western China

    Institute of Scientific and Technical Information of China (English)

    吴忠良; 黄静; 林碧苍

    2002-01-01

    Distribution of apparent stress in Chinese mainland and its surrounding regions was presented using the NEIC broadband radiated energy catalogue and the Harvard CMT catalogue from January 1987 to December 1998. Due to the limitation on the number of samples, reliable results are only for the western China. It is observed that the average apparent stress in Chinese mainland is 0.8 MPa; The maximum apparent stress to the east of the Tibetan plateau is 2.6 MPa; And the average apparent stress in the north-south seismic belt is more than one time higher than its adjacent regions. Distribution pattern of apparent stress seems to have a large-scale correlation with the cumulative energy release level in the 20th century.

  19. Wilcox Group Apparent Thickness, Gulf Coast (wlcxthkg)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Apparent Wilcox Group thickness maps are contoured from location and top information derived from the Petroleum Information (PI) Wells database. The Wilcox...

  20. Viscous Cosmology and Thermodynamics of Apparent Horizon

    Institute of Scientific and Technical Information of China (English)

    M. Akbar

    2008-01-01

    @@ It is shown that the differential form of Friedmann equations of Friedman-Robertson-Walker (FRW) universe can be recast as a similar form of the first law ThdSh=dE + W dV of thermodynamics at the apparent horizon of FRW universe filled with the viscous fluid.It is also shown that by employing the general expression of temperature Th=|k|/2π=1/2π(r)A(1-(r)A/2H(r)A) associated with the apparent horizon of an FRW universe and assumed that the temperature Tm of the energy inside the apparent horizon is proportional to the horizon temperature Tm = bTh,we are able to show that the generalized second law of thermodynamics holds in the Einstein gravity provided Th-Tm/(r)A≤(p+(P)).

  1. Do Acartia tonsa (Dana) eggs regulate their volume and osmolality as salinity changes?

    DEFF Research Database (Denmark)

    Hansen, Benni Winding; Drillet, Guillaume; Pedersen, Morten Foldager;

    2012-01-01

    Subitaneous eggs from an euryhaline calanoid copepod Acartia tonsa were challenged by changes in salinity within the range from full strength salinity, down to zero and up to >70 psu. Egg volume changed immediately, increasing from 2.8 × 105 μm3 at full strength salinity (35 psu) to 3.8 × 105 μm3...... at 0 psu and back to its initial volume when gradually being returned to full strength salinity. Egg osmolality followed the molality of the surrounding water when challenged within a salinity range from 2 to 50 psu. Egg respiration was not affected when eggs kept at 35 psu was exposed to low salinity...... (2 psu). These results suggest that eggs are unable to regulate their volume or osmolality when challenged with changes in salinity. Gradual changes in salinity from 35 to 2 psu and back did not harm the eggs (embryos), since the hatching success remained unaffected by such changes in salinity...

  2. Rubber friction on (apparently) smooth lubricated surfaces

    Science.gov (United States)

    Mofidi, M.; Prakash, B.; Persson, B. N. J.; Albohr, O.

    2008-02-01

    We study rubber sliding friction on hard lubricated surfaces. We show that even if the hard surface appears smooth to the naked eye, it may exhibit short-wavelength roughness, which may make the dominant contribution to rubber friction. That is, the observed sliding friction is mainly due to the viscoelastic deformations of the rubber by the counterface surface asperities. The results presented are of great importance for rubber sealing and other rubber applications involving (apparently) smooth surfaces.

  3. Rubber friction on (apparently) smooth lubricated surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Mofidi, M; Prakash, B [Division of Machine Elements, Luleaa University of Technology, Luleaa SE-97187 (Sweden); Persson, B N J [IFF, FZ-Juelich, 52425 Juelich (Germany); Albohr, O [Pirelli Deutschland AG, 64733 Hoechst/Odenwald, Postfach 1120 (Germany)

    2008-02-27

    We study rubber sliding friction on hard lubricated surfaces. We show that even if the hard surface appears smooth to the naked eye, it may exhibit short-wavelength roughness, which may make the dominant contribution to rubber friction. That is, the observed sliding friction is mainly due to the viscoelastic deformations of the rubber by the counterface surface asperities. The results presented are of great importance for rubber sealing and other rubber applications involving (apparently) smooth surfaces.

  4. Comment: An Apparent Controversy in Auroral Physics

    Science.gov (United States)

    Haerendel, Gerhard

    2007-03-01

    In his article ``A turning point in auroral physics,'' Bryant argued against what he called the `standard' theory of auroral acceleration, according to which the electrons ``gain their energy from static electric fields,'' and offered wave acceleration as an alternative. Because of the importance of the process, not only for the aurora borealis but also for other cosmic plasmas, a clarification of this apparent controversy seems to be in place.

  5. Apparent exchange rate mapping with diffusion MRI.

    Science.gov (United States)

    Lasič, Samo; Nilsson, Markus; Lätt, Jimmy; Ståhlberg, Freddy; Topgaard, Daniel

    2011-08-01

    Water exchange through the cell membranes is an important feature of cells and tissues. The rate of exchange is determined by factors such as membrane lipid composition and organization, as well as the type and activity of aquaporins. A method for noninvasively estimating the rate of water exchange would be useful for characterizing pathological conditions, e.g., tumors, multiple sclerosis, and ischemic stroke, expected to be associated with a change of the membrane barrier properties. This study describes the filter exchange imaging method for determining the rate of water exchange between sites having different apparent diffusion coefficients. The method is based on the filter-exchange pulsed gradient spin-echo NMR spectroscopy experiment, which is here modified to be compatible with the constraints of clinical MR scanners. The data is analyzed using a model-free approach yielding maps of the apparent exchange rate, here being introduced in analogy with the concept of the apparent diffusion coefficient. Proof-of-principle experiments are performed on microimaging and whole-body clinical scanners using yeast suspension phantoms. The limitations and appropriate experimental conditions are examined. The results demonstrate that filter exchange imaging is a fast and reliable method for characterizing exchange, and that it has the potential to become a powerful diagnostic tool.

  6. Gravitational energy as dark energy: Cosmic structure and apparent acceleration

    CERN Document Server

    Wiltshire, David L

    2011-01-01

    Below scales of about 100/h Mpc our universe displays a complex inhomogeneous structure dominated by voids, with clusters of galaxies in sheets and filaments. The coincidence that cosmic expansion appears to start accelerating at the epoch when such structures form has prompted a number of researchers to question whether dark energy is a signature of a failure of the standard cosmology to properly account, on average, for the distribution of matter we observe. Here I discuss the timescape scenario, in which cosmic acceleration is understood as an apparent effect, due to gravitational energy gradients that grow when spatial curvature gradients become significant with the nonlinear growth of cosmic structure. I discuss conceptual issues related to the averaging problem, and their impact on the calibration of local geometry to the solutions of the volume-average evolution equations corrected by backreaction, and the question of nonbaryonic dark matter in the timescape framework. I further discuss recent work on ...

  7. INFLUENCE OF TEXTURE AND MINERALOGY IN APPARENT POROSITY, WATER ABSORPTION AND APPARENT DENSITY OF IGNEOUS ROCKS

    Directory of Open Access Journals (Sweden)

    Ana Paula Meyer

    2014-12-01

    Full Text Available The work consists in evaluating the results of physical indices (apparent porosity, water absorption and apparent density obtained in granitoids exploited as ornamental and revetment stones in the state of São Paulo and Espírito Santo. The results of physical indices were qualified as parameters specification published by Abirochas use and compared the characteristics observed in petrographic samples.

  8. Apparent magnitude of earthshine: a simple calculation

    Science.gov (United States)

    Agrawal, Dulli Chandra

    2016-05-01

    The Sun illuminates both the Moon and the Earth with practically the same luminous fluxes which are in turn reflected by them. The Moon provides a dim light to the Earth whereas the Earth illuminates the Moon with somewhat brighter light which can be seen from the Earth and is called earthshine. As the amount of light reflected from the Earth depends on part of the Earth and the cloud cover, the strength of earthshine varies throughout the year. The measure of the earthshine light is luminance, which is defined in photometry as the total luminous flux of light hitting or passing through a surface. The expression for the earthshine light in terms of the apparent magnitude has been derived for the first time and evaluated for two extreme cases; firstly, when the Sun’s rays are reflected by the water of the oceans and secondly when the reflector is either thick clouds or snow. The corresponding values are -1.30 and -3.69, respectively. The earthshine value -3.22 reported by Jackson lies within these apparent magnitudes. This paper will motivate the students and teachers of physics to look for the illuminated Moon by earthlight during the waning or waxing crescent phase of the Moon and to reproduce the expressions derived here by making use of the inverse-square law of radiation, Planck’s expression for the power in electromagnetic radiation, photopic spectral luminous efficiency function and expression for the apparent magnitude of a body in terms of luminous fluxes.

  9. Apparent life threatening events (ALTE: diagnostic approach

    Directory of Open Access Journals (Sweden)

    Erick Manuel Toro-Monjaraz

    2014-08-01

    Full Text Available Apparent Life-Threatening Events (ALTE are a form of clinical presen- tation of various problems or diseases in children under one year of age. A frequency of 0.6/1000 newborns is estimated. In Mexico, there is no known incidence, systematic approach or guidelines for hospital discharge, so we performed a literature review. Its etiology may be gastrointestinal, neurological, cardiovascular, metabolic, endocrine or-idiopathic. The detailed history and physical examination provide an outline to select the laboratory and imaging studies to perform.

  10. Apparent exchange rate imaging in anisotropic systems

    DEFF Research Database (Denmark)

    Sønderby, Casper Kaae; Lundell, Henrik M; Søgaard, Lise V;

    2014-01-01

    Double-wave diffusion experiments offer the possibility of probing correlation between molecular diffusion at multiple time points. It has recently been shown that this technique is capable of measuring the exchange of water across cellular membranes. The aim of this study was to investigate the ...... the effect of macroscopic tissue anisotropy on the measurement of the apparent exchange rate (AXR) in multicompartment systems.......Double-wave diffusion experiments offer the possibility of probing correlation between molecular diffusion at multiple time points. It has recently been shown that this technique is capable of measuring the exchange of water across cellular membranes. The aim of this study was to investigate...

  11. Apparent speed increases at low luminance

    OpenAIRE

    Vaziri-Pashkam, Maryam; Cavanagh, Patrick

    2008-01-01

    To investigate the effect of luminance on apparent speed, subjects adjusted the speed of a low-luminance rotating grating (0.31 cd/m2) to match that of a high-luminance one (1260 cd/m2). Above 4 Hz, subjects overestimated the speed of the low-luminance grating. This overestimation increased as a function of temporal rate and reached 30% around 10 Hz temporal rates. The speed overestimation became significant once the lower luminance was 2.4 log units lower than the high luminance comparison. ...

  12. Apparent contact angle of an evaporating drop

    Science.gov (United States)

    Morris, S. J. S.

    2012-11-01

    In experiments by Poulard et al. (2005), a sessile drop of perfectly wetting liquid evaporates from a non-heated substrate into an under-saturated mixture of vapour with an inert gas; evaporation is limited by vapour diffusion. The system exhibits an apparent contact angle θ that is a flow property. Under certain conditions, the apparent contact line was stationary relative to the substrate; we predict θ for this case. Observed values of θ are small, allowing lubrication analysis of the liquid film. The liquid and vapour flows are coupled through conditions holding at the phase interface; in particular, vapour partial pressure there is related to the local value of liquid pressure through the Kelvin condition. Because the droplet is shallow, the interfacial conditions can be transferred to the solid-liquid interface at y = 0 . We show that the dimensionless partial pressure p (x , y) and the film thickness h (x) are determined by solving ∇2 p = 0 for y > 0 subject to a matching condition at infinity, and the conditions - p = L hxx +h-3 and (h3px) x + 3py = 0 at y = 0 . The parameter L controls the ratio of Laplace to disjoining pressure. We analyse this b.v.p. for the experimentally-relevant case L --> 0 .

  13. Field signature for apparently superluminal particle motion

    CERN Document Server

    Land, Martin

    2016-01-01

    In the context of Stueckelberg's covariant symplectic mechanics, Horwitz and Aharonovich have proposed a simple mechanism by which a particle traveling below light speed almost everywhere may exhibit a transit time that suggests superluminal motion. This mechanism, which requires precise measurement of the particle velocity, involves a subtle perturbation affecting the particle's recorded time coordinate caused by virtual pair processes. The Stueckelberg framework is particularly well suited to such problems, because it permits pair creation/annihilation at the classical level. In this paper, we study a trajectory of the type proposed by Horwitz and Aharonovich, and derive the Maxwell 4-vector potential associated with the motion. We show that the resulting fields carry a signature associated with the apparent superluminal motion, providing an independent test for the mechanism that does not require direct observation of the trajectory, except at the detector.

  14. Distribution of apparent magnetization for Asia

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Magsat total field anomalies over Asia were used to construct an equivalent magnetization model, which represents the apparent magnetization distribution within an equivalent layer 40 km thick and correlates well with large-scale tectonics, for example, the Kazakhstan, Tarim, Yangtze, India, Sino-Korea and Indochina blocks. The basin, plain, sea basin, and islands are delineated by magnetization lows whereas the plateau and marine ridge correspond to magnetization highs. The boundary between Tibetan Plateau and India marked by a strong gradient along its length coincides with the Yarlung Zangbo River fault roughly. The Tanlu fault belt is the boundary between positive and negative anomalies. This boundary stretches in southwest direction and joins Sanjiang fault belt. The boundary between the Southeast China block and the Yangtze block is also clearly delineated by the magnetization anomalies. Generally, the magnetization boundaries are consistent with the collisional suture of blocks.

  15. Apparent energy distribution of sea waves

    Institute of Scientific and Technical Information of China (English)

    孙孚; 丁平兴

    1995-01-01

    A concept of apparent energy distribution of sea waves is suggested and named "the outer frequency spectrum" to distinguish it from the frequency spectrum in common sense In line with the concept, a kind of outer spectrum with three parameters in Cauchy’ s form is derived theoretically from the joint distribution of wave periods and heights reached previously by the present authors and the Bretschneider spectrum is rededuced simply in a distinct manner. The foundation of mechanics of the similarity between the frequency spectrum in common sense and the outer one is briefly discussed. In view of the fact that Bretschneider spectrum has a wide application in engineering, the advantages and probability of using the outer spectrum as a common one are also considered.

  16. AGN jet physics and apparent opening angles

    CERN Document Server

    Clausen-Brown, Eric; Pushkarev, Alexander B; Kovalev, Yuri Y; Lister, Matthew L

    2013-01-01

    We present a new method to measure Gamma*theta_j in flux-limited samples of active galactic nuclei (AGN) jets, where Gamma is the bulk Lorentz factor and theta_j is the jet's half-opening angle. The Gamma*theta_j parameter is physically important for models of jet launching, and also determines the effectiveness of jet instabilities and magnetic reconnection. We measure Gamma*theta_j by analyzing the observed distribution of apparent opening angles in very long baseline interferometry (VLBI) flux-limited samples of jets, given some prior knowledge of the active galactic nuclei (AGN) radio luminosity function. We then apply this method to the MOJAVE flux-limited sample of radio loud objects and find Gamma*theta_j = 0.1 +- 0.03, which implies that AGN jets are subject to a variety of physical processes that require causal connection.

  17. Ambiguity in Tactile Apparent Motion Perception.

    Directory of Open Access Journals (Sweden)

    Emanuela Liaci

    Full Text Available In von Schiller's Stroboscopic Alternative Motion (SAM stimulus two visually presented diagonal dot pairs, located on the corners of an imaginary rectangle, alternate with each other and induce either horizontal, vertical or, rarely, rotational motion percepts. SAM motion perception can be described by a psychometric function of the dot aspect ratio ("AR", i.e. the relation between vertical and horizontal dot distances. Further, with equal horizontal and vertical dot distances (AR = 1 perception is biased towards vertical motion. In a series of five experiments, we presented tactile SAM versions and studied the role of AR and of different reference frames for the perception of tactile apparent motion.We presented tactile SAM stimuli and varied the ARs, while participants reported the perceived motion directions. Pairs of vibration stimulators were attached to the participants' forearms and stimulator distances were varied within and between forearms. We compared straight and rotated forearm conditions with each other in order to disentangle the roles of exogenous and endogenous reference frames.Increasing the tactile SAM's AR biased perception towards vertical motion, but the effect was weak compared to the visual modality. We found no horizontal disambiguation, even for very small tactile ARs. A forearm rotation by 90° kept the vertical bias, even though it was now coupled with small ARs. A 45° rotation condition with crossed forearms, however, evoked a strong horizontal motion bias.Existing approaches to explain the visual SAM bias fail to explain the current tactile results. Particularly puzzling is the strong horizontal bias in the crossed-forearm conditions. In the case of tactile apparent motion, there seem to be no fixed priority rule for perceptual disambiguation. Rather the weighting of available evidence seems to depend on the degree of stimulus ambiguity, the current situation and on the perceptual strategy of the individual

  18. Apparent life-threatening event in infancy

    Science.gov (United States)

    Choi, Hee Joung

    2016-01-01

    An apparent life-threatening event (ALTE) is defined as the combination of clinical presentations such as apnea, marked change in skin and muscle tone, gagging, or choking. It is a frightening event, and it predominantly occurs during infancy at a mean age of 1–3 months. The causes of ALTE are categorized into problems that are: gastrointestinal (50%), neurological (30%), respiratory (20%), cardiovascular (5%), metabolic and endocrine (2%–5%), or others such as child abuse. Up to 50% of ALTEs are idiopathic, where the cause cannot be diagnosed. Infants with an ALTE are often asymptomatic at hospital and there is no standard workup protocol for ALTE. Therefore, a detailed initial history and physical examination are important to determine the extent of the medical evaluation and treatment. Regardless of the cause of an ALTE, all infants with an ALTE should require hospitalization and continuous cardiorespiratory monitoring and evaluation for at least 24 hours. The natural course of ALTEs has seemed benign, and the outcome is generally associated with the affected infants' underlying disease. In conclusion, systemic diagnostic evaluation and adequate treatment increases the survival and quality of life for most affected infants.

  19. Apparent exchange rate for breast cancer characterization.

    Science.gov (United States)

    Lasič, Samo; Oredsson, Stina; Partridge, Savannah C; Saal, Lao H; Topgaard, Daniel; Nilsson, Markus; Bryskhe, Karin

    2016-05-01

    Although diffusion MRI has shown promise for the characterization of breast cancer, it has low specificity to malignant subtypes. Higher specificity might be achieved if the effects of cell morphology and molecular exchange across cell membranes could be disentangled. The quantification of exchange might thus allow the differentiation of different types of breast cancer cells. Based on differences in diffusion rates between the intra- and extracellular compartments, filter exchange spectroscopy/imaging (FEXSY/FEXI) provides non-invasive quantification of the apparent exchange rate (AXR) of water between the two compartments. To test the feasibility of FEXSY for the differentiation of different breast cancer cells, we performed experiments on several breast epithelial cell lines in vitro. Furthermore, we performed the first in vivo FEXI measurement of water exchange in human breast. In cell suspensions, pulsed gradient spin-echo experiments with large b values and variable pulse duration allow the characterization of the intracellular compartment, whereas FEXSY provides a quantification of AXR. These experiments are very sensitive to the physiological state of cells and can be used to establish reliable protocols for the culture and harvesting of cells. Our results suggest that different breast cancer subtypes can be distinguished on the basis of their AXR values in cell suspensions. Time-resolved measurements allow the monitoring of the physiological state of cells in suspensions over the time-scale of hours, and reveal an abrupt disintegration of the intracellular compartment. In vivo, exchange can be detected in a tumor, whereas, in normal tissue, the exchange rate is outside the range experimentally accessible for FEXI. At present, low signal-to-noise ratio and limited scan time allows the quantification of AXR only in a region of interest of relatively large tumors.

  20. Apparent diffusion coefficient of normal adrenal glands

    Directory of Open Access Journals (Sweden)

    Sara Reis Teixeira

    Full Text Available Abstract Objective: To assess the feasibility and reliability of apparent diffusion coefficient (ADC measurements of normal adrenal glands. Materials and methods: This was a retrospective study involving 32 healthy subjects, divided into two groups: prepubertal (PreP, n = 12, aged from 2 months to 12.5 years (4 males; 8 females; and postpubertal (PostP, n = 20, aged from 11.9 to 61 years (5 males; 15 females. Diffusion-weighted magnetic resonance imaging (DW-MRI sequences were acquired at a 1.5 T scanner using b values of 0, 20, 500, and 1000 s/mm2. Two radiologists evaluated the images. ADC values were measured pixel-by-pixel on DW-MRI scans, and automatic co-registration with the ADC map was obtained. Results: Mean ADC values for the right adrenal glands were 1.44 × 10-3 mm2/s for the PreP group and 1.23 × 10-3 mm2/s for the PostP group, whereas they were 1.58 × 10-3 mm2/s and 1.32 × 10-3 mm2/s, respectively, for the left glands. ADC values were higher in the PreP group than in the PostP group (p < 0.05. Agreement between readers was almost perfect (intraclass correlation coefficient, 0.84-0.94; p < 0.05. Conclusion: Our results demonstrate the feasibility and reliability of performing DW-MRI measurements of normal adrenal glands. They could also support the feasibility of ADC measurements of small structures.

  1. Apparent diffusion coefficient of normal adrenal glands*

    Science.gov (United States)

    Teixeira, Sara Reis; Elias, Paula Condé Lamparelli; Leite, Andrea Farias de Melo; de Oliveira, Tatiane Mendes Gonçalves; Muglia, Valdair Francisco; Elias Junior, Jorge

    2016-01-01

    Objective To assess the feasibility and reliability of apparent diffusion coefficient (ADC) measurements of normal adrenal glands. Materials and methods This was a retrospective study involving 32 healthy subjects, divided into two groups: prepubertal (PreP, n = 12), aged from 2 months to 12.5 years (4 males; 8 females); and postpubertal (PostP, n = 20), aged from 11.9 to 61 years (5 males; 15 females). Diffusion-weighted magnetic resonance imaging (DW-MRI) sequences were acquired at a 1.5 T scanner using b values of 0, 20, 500, and 1000 s/mm2. Two radiologists evaluated the images. ADC values were measured pixel-by-pixel on DW-MRI scans, and automatic co-registration with the ADC map was obtained. Results Mean ADC values for the right adrenal glands were 1.44 × 10-3 mm2/s for the PreP group and 1.23 × 10-3 mm2/s for the PostP group, whereas they were 1.58 × 10-3 mm2/s and 1.32 × 10-3 mm2/s, respectively, for the left glands. ADC values were higher in the PreP group than in the PostP group (p < 0.05). Agreement between readers was almost perfect (intraclass correlation coefficient, 0.84-0.94; p < 0.05). Conclusion Our results demonstrate the feasibility and reliability of performing DW-MRI measurements of normal adrenal glands. They could also support the feasibility of ADC measurements of small structures. PMID:28057963

  2. Measurement and Correlation on Viscosity and Apparent Molar Volume of Ternary System for L-ascorbic Acid in Aqueous D-Glucose and Sucrose Solutions%L-抗坏血酸在葡萄糖和蔗糖溶液中的黏度及其热力学性质的研究

    Institute of Scientific and Technical Information of China (English)

    赵长伟; 马沛生

    2003-01-01

    Viscosities and densities at several temperatures from 293.15 K to 313.15 K are reported for L-ascorbic acid in aqueous glucose and sucrose solutions at different concentrations. The parameters of density, viscosity coefficient B and partial molar volume are calculated by regression. The experimental results show that densities and viscosities decrease as temperature increases at the same solute and solvent (glucose and sucrose aqueous solution) concentrations, and increase with concentration of glucose and sucrose at the same solute concentration and temperature. B increases with concentration of glucose and sucrose and temperature. L-ascorbic acid is structure-breaker or structure-making for the glucose and sucrose aqueous solutions. Furthermore, the solute-solvent interactions in ternary systems of water-glucose-electrolyte and water-sucrose-electrolyte are discussed.

  3. Mechanics of Apparent Horizon in Two Dimensional Dilaton Gravity

    CERN Document Server

    Cai, Rong-Gen

    2016-01-01

    In this article, we give a definition of apparent horizon in a two dimensional general dilaton gravity theory. With this definition, we construct the mechanics of the apparent horizon by introducing a quasi-local energy of the theory. Our discussion generalizes the apparent horizons mechanics in general spherically symmetric spactimes in four or higher dimensions to the two dimensional dilaton gravity case.

  4. The influence of spontaneous brain oscillations on apparent motion perception.

    Science.gov (United States)

    Sanders, Lia Lira Olivier; Auksztulewicz, Ryszard; Hohlefeld, Friederike U; Busch, Niko A; Sterzer, Philipp

    2014-11-15

    A good example of inferential processes in perception is long-range apparent motion (AM), the illusory percept of visual motion that occurs when two spatially distinct stationary visual objects are presented in alternating sequence. The AM illusion is strongest at presentation frequencies around 3 Hz. At lower presentation frequencies, the percept varies from trial to trial between AM and sequential alternation, while at higher frequencies perception varies between AM and two simultaneously flickering objects. Previous studies have demonstrated that prestimulus alpha oscillations explain trial-to-trial variability in detection performance for visual stimuli presented at threshold. In the present study, we investigated whether fluctuations of prestimulus alpha oscillations can also account for variations in AM perception. Prestimulus alpha power was stronger when observers reported AM perception in subsequent trials with low presentation frequencies, while at high presentation frequencies there were no significant differences in alpha power preceding AM and veridical flicker perception. Moreover, when observers perceived AM the prestimulus functional connectivity between frontal and occipital channels was increased in the alpha band, as revealed by the imaginary part of coherency, which is insensitive to artefacts from volume conduction. Dynamic causal modelling of steady-state responses revealed that the most likely direction of this fronto-occipital connectivity was from frontal to occipital sources. These results point to a role of ongoing alpha oscillations in the inferential process that gives rise to the perception of AM and suggest that fronto-occipital interactions bias perception towards internally generated predictions.

  5. Discrimination of paediatric brain tumours using apparent diffusion coefficient histograms

    Energy Technology Data Exchange (ETDEWEB)

    Bull, Jonathan G.; Clark, Christopher A. [UCL Institute of Child Health, Imaging and Biophysics Unit, London (United Kingdom); Saunders, Dawn E. [Great Ormond Street Hospital for Children NHS Trust, Department of Radiology, London (United Kingdom)

    2012-02-15

    To determine if histograms of apparent diffusion coefficients (ADC) can be used to differentiate paediatric brain tumours. Imaging of histologically confirmed tumours with pre-operative ADC maps were reviewed (54 cases, 32 male, mean age 6.1 years; range 0.1-15.8 years) comprising 6 groups. Whole tumour ADC histograms were calculated; normalised for volume. Stepwise logistic regression analysis was used to differentiate tumour types using histogram metrics, initially for all groups and then for specific subsets. All 6 groups (5 dysembryoplastic neuroectodermal tumours, 22 primitive neuroectodermal tumours (PNET), 5 ependymomas, 7 choroid plexus papillomas, 4 atypical teratoid rhabdoid tumours (ATRT) and 9 juvenile pilocytic astrocytomas (JPA)) were compared. 74% (40/54) were correctly classified using logistic regression of ADC histogram parameters. In the analysis of posterior fossa tumours, 80% of ependymomas, 100% of astrocytomas and 94% of PNET-medulloblastoma were classified correctly. All PNETs were discriminated from ATRTs (22 PNET and 4 supratentorial ATRTs) (100%). ADC histograms are useful in differentiating paediatric brain tumours, in particular, the common posterior fossa tumours of childhood. PNETs were differentiated from supratentorial ATRTs, in all cases, which has important implications in terms of clinical management. (orig.)

  6. Gas Phase Pressure Effects on the Apparent Thermal Conductivity of JSC-1A Lunar Regolith Simulant

    Science.gov (United States)

    Yuan, Zeng-Guang; Kleinhenz, Julie E.

    2011-01-01

    Gas phase pressure effects on the apparent thermal conductivity of a JSC-1A/air mixture have been experimentally investigated under steady state thermal conditions from 10 kPa to 100 kPa. The result showed that apparent thermal conductivity of the JSC-1A/air mixture decreased when pressure was lowered to 80 kPa. At 10 kPa, the conductivity decreased to 0.145 W/m/degree C, which is significantly lower than 0.196 W/m/degree C at 100 kPa. This finding is consistent with the results of previous researchers. The reduction of the apparent thermal conductivity at low pressures is ascribed to the Knudsen effect. Since the characteristic length of the void space in bulk JSC-1A varies over a wide range, both the Knudsen regime and continuum regime can coexist in the pore space. The volume ratio of the two regimes varies with pressure. Thus, as gas pressure decreases, the gas volume controlled by Knudsen regime increases. Under Knudsen regime the resistance to the heat flow is higher than that in the continuum regime, resulting in the observed pressure dependency of the apparent thermal conductivity.

  7. Apparent density patterns in subchondral bone of the sloth and anteater forelimb.

    Science.gov (United States)

    Patel, Biren A; Carlson, Kristian J

    2008-10-23

    Vertebrate morphologists often are interested in inferring limb-loading patterns in animals characterized by different locomotor repertoires. Because bone apparent density (i.e. mass per unit volume of bone inclusive of porosities) is a determinant of compressive strength, and thus indicative of compressive loading, recent comparative studies in primates have proposed a structure-function relationship between apparent density of subchondral bone and locomotor behaviours that vary in compressive loading. If such patterns are found in other mammals, then these relationships would be strengthened further. Here, we examine the distal radius of suspensory sloths that generally load their forelimbs (FLs) in tension and of quadrupedal anteaters that generally load their FLs in compression. Computed tomography osteoabsorptiometry was used to visualize the patterns in subchondral apparent density. Suspensory sloths exhibit relatively smaller areas of high apparent density than quadrupedal anteaters. This locomotor-based pattern is analogous to the pattern observed in suspensory and quadrupedal primates. Similarity between xenarthran and primate trends suggests broad-scale applicability for analysing subchondral bone apparent density and supports the idea that bone functionally alters its material properties in response to locomotor behaviours.

  8. Thermodynamic Behavior of Friedmann Equations at Apparent Horizon of FRW Universe

    CERN Document Server

    Akbar, M; Cai, Rong-Gen

    2006-01-01

    It is shown that the differential form of Friedmann equations of a FRW universe can be rewritten as a thermodynamical identity $TdS = dE + PdV$ at apparent horizon, where $E$ is the Misner-Sharp energy, $V$ is the volume inside the apparent horizon, and $P$ is the pressure of the perfect fluid in the universe. From the thermodynamic identity one can derive that the apparent horizon $\\tilde r_A$ has associated temperature $T=1/2\\pi \\tilde r_A$ and entropy $S= A/4G$ in Einstein general relativity, where $A$ is the area of apparent horizon. We extend our procedure to the Gauss-Bonnet gravity and more general Lovelock gravity and show that the field equations in these gravities can also be identified as a thermodynamical system satisfying $TdS = dE + PdV$ at the apparent horizon of FRW universe with entropy $S$ being given by expression previously known via black hole thermodynamics.

  9. Thermodynamics of the Apparent Horizon in FRW Universe with Massive Gravity

    Institute of Scientific and Technical Information of China (English)

    LI Hui; ZHANG Yi

    2013-01-01

    Applying Clausius relation with energy-supply defined by the unified first law of thermodynamics formalism to the apparent horizon of a massive gravity model in cosmology proposed lately,the corrected entropic formula of the apparent horizon is obtained with the help of the modified Friedmann equations.This entropy-area relation,together with the identified Misner-Sharp internal energy,verifies the first law of thermodynamics for the apparent horizon with a volume change term for consistency.On the other hand,by means of the corrected entropy-area formula and the Clausius relation δQ =T dS,where the heat flow δQ is the energy-supply of pure matter projecting on the vector ξ tangent to the apparent horizon and should be looked on as the amount of energy crossing the apparent horizon during the time interval dt and the temperature of the apparent horizon for energy crossing during the same interval is 1/(2π(r)A),the modified Friedmann equations governing the dynamical evolution of the universe are reproduced with the known energy density and pressure of massive graviton.The integration constant is found to correspond to a cosmological term which could be absorbed into the energy density of matter.Having established the correspondence of massive cosmology with the unified first law of thermodynamics on the apparent horizon,the validity of the generalized second law of thermodynamics is also discussed by assuming the thermal equilibrium between the apparent horizon and the matter field bounded by the apparent horizon.It is found that,in the limit Hc → 0,which recovers the Minkowski reference metric solution in the flat case,the generalized second law of thermodynamics holds if α3 + 4α4 < 0.Without this condition,even for the simplest model of dRGT massive cosmology with α3 =α4 =0,the generalized second law of thermodynamics could be violated.

  10. Observations on the Apparent Solubility of Carbonate-Apatites.

    Science.gov (United States)

    Shellis; Lee; Wilson

    1999-10-15

    Previousreports indicating that the apparent solubilities of carbonate-apatites are low appear to conflict with findings that carbonate incorporation into the apatite structure tends to reduce stability. Carbonate-apatites were prepared by a precipitation method and by hydrolysis of monetite and brushite. Apparent solubility profiles were determined by measuring dissolution after exposure for 24 h to acetate buffers with known saturations with respect to hydroxyapatite. All preparations showed a range of apparent solubilities, in agreement with previous work. Precipitated samples had higher apparent solubilities than samples prepared by hydrolysis and this was correlated with differences in crystallinity. Further experiments showed that pyrophosphate ion reduced the apparent solubility, but it was concluded that pyrophosphate occurring naturally in synthetic apatites would be insufficient to cause low apparent solubilities. Microscopical observations showed that precipitated carbonate-apatites were composed of small crystals of uniform size, whereas carbonate-apatites prepared by hydrolysis consisted of both small crystals and very large crystals. The low apparent solubilities observed in the latter preparations are attributed to the large crystals. The surface phenomena possibly involved in apparent solubility behavior are discussed. Copyright 1999 Academic Press.

  11. "Apparent Weight": A Concept that Is Confusing and Unnecessary

    Science.gov (United States)

    Bartlett, Albert A.

    2010-01-01

    Two recent articles make prominent use of the concept of "apparent weight." The concept of "apparent weight" leads to two confusing inconsistencies. We need to know that with very little change in our representations, we can give our students an improved understanding of "weight" without ever having to invent the appealing but confusing concept of…

  12. Thermodynamics of apparent horizon and modified Friedman equations

    CERN Document Server

    Sheykhi, Ahmad

    2010-01-01

    Starting from the first law of thermodynamics, $dE=T_hdS_h+WdV$, at apparent horizon of a FRW universe, and assuming that the associated entropy with apparent horizon has a quantum corrected relation, $S=\\frac{A}{4G}-\\alpha \\ln \\frac{A}{4G}+\\beta \\frac{4G}{A}$, we derive modified Friedmann equations describing the dynamics of the universe with any spatial curvature. We also examine the time evolution of the total entropy including the quantum corrected entropy associated with the apparent horizon together with the matter field entropy inside the apparent horizon. Our study shows that, with the local equilibrium assumption, the generalized second law of thermodynamics is fulfilled in a region enclosed by the apparent horizon.

  13. Multiple weather factors affect apparent survival of European passerine birds.

    Directory of Open Access Journals (Sweden)

    Volker Salewski

    Full Text Available Weather affects the demography of animals and thus climate change will cause local changes in demographic rates. In birds numerous studies have correlated demographic factors with weather but few of those examined variation in the impacts of weather in different seasons and, in the case of migrants, in different regions. Using capture-recapture models we correlated weather with apparent survival of seven passerine bird species with different migration strategies to assess the importance of selected facets of weather throughout the year on apparent survival. Contrary to our expectations weather experienced during the breeding season did not affect apparent survival of the target species. However, measures for winter severity were associated with apparent survival of a resident species, two short-distance/partial migrants and a long-distance migrant. Apparent survival of two short distance migrants as well as two long-distance migrants was further correlated with conditions experienced during the non-breeding season in Spain. Conditions in Africa had statistically significant but relatively minor effects on the apparent survival of the two long-distance migrants but also of a presumably short-distance migrant and a short-distance/partial migrant. In general several weather effects independently explained similar amounts of variation in apparent survival for the majority of species and single factors explained only relatively low amounts of temporal variation of apparent survival. Although the directions of the effects on apparent survival mostly met our expectations and there are clear predictions for effects of future climate we caution against simple extrapolations of present conditions to predict future population dynamics. Not only did weather explains limited amounts of variation in apparent survival, but future demographics will likely be affected by changing interspecific interactions, opposing effects of weather in different seasons, and

  14. Multiple weather factors affect apparent survival of European passerine birds.

    Science.gov (United States)

    Salewski, Volker; Hochachka, Wesley M; Fiedler, Wolfgang

    2013-01-01

    Weather affects the demography of animals and thus climate change will cause local changes in demographic rates. In birds numerous studies have correlated demographic factors with weather but few of those examined variation in the impacts of weather in different seasons and, in the case of migrants, in different regions. Using capture-recapture models we correlated weather with apparent survival of seven passerine bird species with different migration strategies to assess the importance of selected facets of weather throughout the year on apparent survival. Contrary to our expectations weather experienced during the breeding season did not affect apparent survival of the target species. However, measures for winter severity were associated with apparent survival of a resident species, two short-distance/partial migrants and a long-distance migrant. Apparent survival of two short distance migrants as well as two long-distance migrants was further correlated with conditions experienced during the non-breeding season in Spain. Conditions in Africa had statistically significant but relatively minor effects on the apparent survival of the two long-distance migrants but also of a presumably short-distance migrant and a short-distance/partial migrant. In general several weather effects independently explained similar amounts of variation in apparent survival for the majority of species and single factors explained only relatively low amounts of temporal variation of apparent survival. Although the directions of the effects on apparent survival mostly met our expectations and there are clear predictions for effects of future climate we caution against simple extrapolations of present conditions to predict future population dynamics. Not only did weather explains limited amounts of variation in apparent survival, but future demographics will likely be affected by changing interspecific interactions, opposing effects of weather in different seasons, and the potential for

  15. Calculation of Apparent Activation Energy of Coal Oxidation at Low Temperatures by Measuring CO Yield

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    By analyzing previous studies on activation energy of coal oxidation at low temperatures, a theoretical calculation model of apparent activation energy is established. Yield of CO is measured by using the characteristic detector of coal oxidation at 30-90 ℃. The impact of parameters, such as airflow and particle size, on activation energies is analyzed. Finally, agreement was obtained between activation energies and the dynamic oxygen absorbed in order to test the accuracy of the model. The results show that: 1) a positive exponential relation between concentration of CO and temperature in the process of the experiment is obtained: increases are almost identical and the initial CO is low; 2) the apparent activation energies increase gradually with the sizes of particle at the same airflow, but the gradients increase at a decreasing rate; 3) the apparent activation energies increase linearly with airflow. For the five coal particles, the differences among the energies are relatively high when the airflow was low, but the differences were low when the airflow was high; 4) the optimum sizes of particle, 0.125-0.25 mm, and the optimum volume of airflow, 100 mL/min, are determined from the model; 5) the apparent activation energies decrease with an increase in oxygen absorbed. A negative exponential relation between the two is obtained.

  16. The effect of visual apparent motion on audiovisual simultaneity.

    Science.gov (United States)

    Kwon, Jinhwan; Ogawa, Ken-ichiro; Miyake, Yoshihiro

    2014-01-01

    Visual motion information from dynamic environments is important in multisensory temporal perception. However, it is unclear how visual motion information influences the integration of multisensory temporal perceptions. We investigated whether visual apparent motion affects audiovisual temporal perception. Visual apparent motion is a phenomenon in which two flashes presented in sequence in different positions are perceived as continuous motion. Across three experiments, participants performed temporal order judgment (TOJ) tasks. Experiment 1 was a TOJ task conducted in order to assess audiovisual simultaneity during perception of apparent motion. The results showed that the point of subjective simultaneity (PSS) was shifted toward a sound-lead stimulus, and the just noticeable difference (JND) was reduced compared with a normal TOJ task with a single flash. This indicates that visual apparent motion affects audiovisual simultaneity and improves temporal discrimination in audiovisual processing. Experiment 2 was a TOJ task conducted in order to remove the influence of the amount of flash stimulation from Experiment 1. The PSS and JND during perception of apparent motion were almost identical to those in Experiment 1, but differed from those for successive perception when long temporal intervals were included between two flashes without motion. This showed that the result obtained under the apparent motion condition was unaffected by the amount of flash stimulation. Because apparent motion was produced by a constant interval between two flashes, the results may be accounted for by specific prediction. In Experiment 3, we eliminated the influence of prediction by randomizing the intervals between the two flashes. However, the PSS and JND did not differ from those in Experiment 1. It became clear that the results obtained for the perception of visual apparent motion were not attributable to prediction. Our findings suggest that visual apparent motion changes temporal

  17. A comparison of concentration measurement techniques for the estimation of the apparent mass diffusion coefficient

    Directory of Open Access Journals (Sweden)

    L.M. Pereira

    2001-09-01

    Full Text Available In this article we compare two different techniques to measure the concentration of saline solutions for the identification of the apparent mass diffusion coefficient in soils saturated with distilled water. They are the radiation measurement technique and the electrical conductivity measurement technique. These techniques are compared in terms of measured quantities, sensitivity coefficients with respect to unknown parameters and the determinant of the information matrix. The apparent mass diffusion coefficient is estimated by utilizing simulated measurements containing random errors. The Levenberg-Marquardt method of minimization of the least-squares norm is used as the parameter estimation procedure. The effects of the volume of saline solution injected into the column devised for the experiments on the accuracy of the estimated parameters are also addressed in this article.

  18. Volume Entropy

    CERN Document Server

    Astuti, Valerio; Rovelli, Carlo

    2016-01-01

    Building on a technical result by Brunnemann and Rideout on the spectrum of the Volume operator in Loop Quantum Gravity, we show that the dimension of the space of the quadrivalent states --with finite-volume individual nodes-- describing a region with total volume smaller than $V$, has \\emph{finite} dimension, bounded by $V \\log V$. This allows us to introduce the notion of "volume entropy": the von Neumann entropy associated to the measurement of volume.

  19. Total individual ion activity coefficients of calcium and carbonate in seawater at 25°C and 35%. salinity, and implications to the agreement between apparent and thermodynamic constants of calcite and aragonite

    Science.gov (United States)

    Plummer, L. Neil; Sundquist, Eric T.

    1982-01-01

    We have calculated the total individual ion activity coefficients of carbonate and calcium,  and , in seawater. Using the ratios of stoichiometric and thermodynamic constants of carbonic acid dissociation and total mean activity coefficient data measured in seawater, we have obtained values which differ significantly from those widely accepted in the literature. In seawater at 25°C and 35%. salinity the (molal) values of  and  are 0.038 ± 0.002 and 0.173 ± 0.010, respectively. These values of  and  are independent of liquid junction errors and internally consistent with the value . By defining  and  on a common scale (), the product  is independent of the assigned value of  and may be determined directly from thermodynamic measurements in seawater. Using the value  and new thermodynamic equilibrium constants for calcite and aragonite, we show that the apparent constants of calcite and aragonite are consistent with the thermodynamic equilibrium constants at 25°C and 35%. salinity. The demonstrated consistency between thermodynamic and apparent constants of calcite and aragonite does not support a hypothesis of stable Mg-calcite coatings on calcite or aragonite surfaces in seawater, and suggests that the calcite critical carbonate ion curve of Broecker and Takahashi (1978,Deep-Sea Research25, 65–95) defines the calcite equilibrium boundary in the oceans, within the uncertainty of the data.

  20. Analysis of Apparent Elasticity Constants of Woven Fabrics

    Institute of Scientific and Technical Information of China (English)

    董侠; 张建春; 张燕

    2001-01-01

    The woven fabric can be defined as orthogonal elastomer if the extension force that puts on the fabric is very small. Based on the precondition, the apparent elasticity constants of a woven fabric were analyzed theoretically in the paper. The bias angle (which is between weft yarns and extension direction ) affects apparent elasticity modulus and elasticity coefficient of the fabric in the extension direction. And the experiment describes fluxes of elasticity constants going with the bias angle of the fabric.

  1. Standard Test Method for Water Absorption, Bulk Density, Apparent Porosity, and Apparent Specific Gravity of Fired Whiteware Products

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2006-01-01

    1.1 This test method covers procedures for determining water absorption, bulk density, apparent porosity, and apparent specific gravity of fired unglazed whiteware products. 1.2 This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety problems associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  2. Prevalence of upper airway obstruction in patients with apparently asymptomatic euthyroid multi nodular goitre

    Directory of Open Access Journals (Sweden)

    Sunil K Menon

    2011-01-01

    Full Text Available Aims: To study the prevalence of upper airway obstruction (UAO in "apparently asymptomatic" patients with euthyroid multinodular goitre (MNG and find correlation between clinical features, UAO on pulmonary function test (PFT and tracheal narrowing on computerised tomography (CT. Materials and Methods: Consecutive patients with apparently asymptomatic euthyroid MNG attending thyroid clinic in a tertiary centre underwent clinical examination to elicit features of UAO, PFT, and CT of neck and chest. Statistical Analysis Used: Statistical analysis was done with SPSS version 11.5 using paired t-test, Chi square test, and Fisher′s exact test. P value of <0.05 was considered to be significant. Results: Fifty-six patients (52 females and four males were studied. The prevalence of UAO (PFT and significant tracheal narrowing (CT was 14.3%. and 9.3%, respectively. Clinical features failed to predict UAO or significant tracheal narrowing. Tracheal narrowing (CT did not correlate with UAO (PFT. Volume of goitre significantly correlated with degree of tracheal narrowing. Conclusions: Clinical features do not predict UAO on PFT or tracheal narrowing on CT in apparently asymptomatic patients with euthyroid MNG.

  3. The uptake of manganese ions and the apparent thermal transition of the erythrocyte membranes.

    Science.gov (United States)

    Morariu, V V; Ionescu, M S; Frangopol, M; Grosescu, R; Lupu, M; Frangopol, P T

    1986-08-01

    The nuclear magnetic resonance manganese doping technique is currently used for the determination of the water diffusional exchange time through human erythrocyte membranes. An apparent thermal transition at 26 degrees C was noticed at 18-30 mM manganese doping in the suspending solution. An analysis in terms of a two-phase nuclear spin exchanging system revealed that apparent thermal transitions are expected to occur in the upper and lower temperature regions. They represent a shift from intermediate exchange rates where water diffusion through the membrane is dominant to either fast or slow exchange rates where proton relaxation is the controlling process. The lower temperature apparent transition may be altered by the intracellular manganese concentration; the lower the Mn2+ concentration the lower the transition. Also according to this interpretation only a fraction of the erythrocytes are significantly permeated by Mn2+. The upper transition depends on the Mn2+ concentration in the extracellular volume; it decreases with decreasing Mn2+ concentration.

  4. Study of multi black hole and ring singularity apparent horizons

    CERN Document Server

    Jaramillo, Gabriela

    2010-01-01

    We study critical black hole separations for the formation of a common apparent horizon in systems of $N$ - black holes in a time symmetric configuration. We study in detail the aligned equal mass cases for $N=2,3,4,5$, and relate them to the unequal mass binary black hole case. We then study the apparent horizon of the time symmetric initial geometry of a ring singularity of different radii. The apparent horizon is used as indicative of the location of the event horizon in an effort to predict a critical ring radius that would generate an event horizon of toroidal topology. We found that a good estimate for this ring critical radius is $20/(3\\pi) M$. We briefly discuss the connection of this two cases through a discrete black hole 'necklace' configuration.

  5. Shape reconstruction from apparent contours theory and algorithms

    CERN Document Server

    Bellettini, Giovanni; Paolini, Maurizio

    2015-01-01

    Motivated by a variational model concerning the depth of the objects in a picture and the problem of hidden and illusory contours, this book investigates one of the central problems of computer vision: the topological and algorithmic reconstruction of a smooth three dimensional scene starting from the visible part of an apparent contour. The authors focus their attention on the manipulation of apparent contours using a finite set of elementary moves, which correspond to diffeomorphic deformations of three dimensional scenes. A large part of the book is devoted to the algorithmic part, with implementations, experiments, and computed examples. The book is intended also as a user's guide to the software code appcontour, written for the manipulation of apparent contours and their invariants. This book is addressed to theoretical and applied scientists working in the field of mathematical models of image segmentation.

  6. Foliation dependence of black hole apparent horizons in spherical symmetry

    CERN Document Server

    Faraoni, Valerio; Firouzjaee, Javad T; Helou, Alexis; Musco, Ilia

    2016-01-01

    Numerical studies of gravitational collapse to black holes make use of apparent horizons, which are intrinsically foliation-dependent. We expose the problem and discuss possible solutions using the Hawking quasilocal mass. In spherical symmetry, we present a physically sensible approach to the problem by restricting to spherically symmetric spacetime slicings. In spherical symmetry the apparent horizons are gauge-independent in any spherically symmetric foliation but physical quantities associated with them, such as surface gravity and temperature, are not. The widely used comoving and Kodama foliations, which are of particular interest, are discussed in detail.

  7. Foliation dependence of black hole apparent horizons in spherical symmetry

    Science.gov (United States)

    Faraoni, Valerio; Ellis, George F. R.; Firouzjaee, Javad T.; Helou, Alexis; Musco, Ilia

    2017-01-01

    Numerical studies of gravitational collapse to black holes make use of apparent horizons, which are intrinsically foliation dependent. We expose the problem and discuss possible solutions using the Hawking-Hayward quasilocal mass. In spherical symmetry, we present a physically sensible approach to the problem by restricting to spherically symmetric spacetime slicings. In spherical symmetry, the apparent horizons enjoy a restricted gauge independence in any spherically symmetric foliation, but physical quantities associated with them, such as surface gravity and temperature, are fully gauge dependent. The widely used comoving and Kodama foliations, which are of particular interest, are discussed in detail as examples.

  8. Effects of liquid morphology and distribution on the apparent properties of porous media made of stacked particles

    Directory of Open Access Journals (Sweden)

    Mingzhi Yu

    2015-05-01

    Full Text Available To understand the effects of liquid morphology on the apparent transfer properties of porous media formed by stacked particles, the authors investigate the particles’ aggregation state, apparent volume, thermal conductivity, and electrical conductivity of wet stacked glass beads. It shows that the liquid mainly exists as liquid bridges when the liquid content is low and connects each other when high. The transformation of liquid morphology and distribution influences the liquid effects on particles, thus changing the aggregation state of the particles and the apparent properties of the porous media in turn. A model is developed for predicting the critical liquid content at which the liquid morphology shifts from the state of liquid bridges into the state of interconnectedness. The prediction from the model is in good agreement with the experiment.

  9. Common mechanisms in apparent motion perception and visual pattern matching.

    Science.gov (United States)

    Larsen, Axel; Bundesen, Claus

    2009-12-01

    Common mechanisms in apparent motion perception and visual pattern matching. Scandinavian Journal of Psychology, 50, 526-534.There are close functional similarities between apparent motion perception and visual pattern matching. In particular, striking functional similarities have been demonstrated between perception of rigid objects in apparent motion and purely mental transformations of visual size and orientation used in comparisons of objects with respect to shape but regardless of size and orientation. In both cases, psychophysical data suggest that differences in visual size are resolved as differences in depth, such that transformation of size is done by translation in depth. Furthermore, the process of perceived or imagined translation appears to be stepwise additive such that a translation over a long distance consists of a sequence of smaller translations, the durations of these steps being additive. Both perceived and imagined rotation also appear to be stepwise additive, and combined transformations of size and orientation appear to be done by alternation of small steps of pure translation and small steps of pure rotation. The functional similarities suggest that common mechanisms underlie perception of apparent motion and purely mental transformations. In line with this suggestion, functional brain imaging has isolated neural structures in motion area MT used in mental transformation of size.

  10. Eudynamis Minima, an apparently new Cuckoo from Southwestern New Guinea

    NARCIS (Netherlands)

    Oort, van E.D.

    1911-01-01

    Only an adult male of this apparently new form of the genus Eudynamis has been collected near Bivak Island, in the Noord River, Southwestern New Guinea, at 9 January 1910 by the members of the last Lorentz-expedition to the snowy mountains. (Coll. Lorentz n°. 508). The plumage is black, glossed with

  11. Apparent horizons in Clifton-Mota-Barrow inhomogeneous universe

    CERN Document Server

    Vitagliano, Vincenzo; Sotiriou, Thomas P; Liberati, Stefano

    2013-01-01

    We analyze the apparent horizon dynamics in the inhomogeneous Clifton-Mota-Barrow solution of Brans-Dicke theory. This solution models a central matter configuration embedded in a cosmological background. In certain regions of the parameter space we find solutions exhibiting dynamical creation or merging of two horizons.

  12. Studying the cosmological apparent horizon with quasistatic coordinates

    Indian Academy of Sciences (India)

    Rui-Yan Yu; Towe Wang

    2013-02-01

    This article aims at a natural generalization of the static coordinates to the ( + 1)-dimensional Friedmann–Lemaître–Robertson–Walker (FLRW) Universe. After demonstrating a no-go theorem, we put forward the quasistatic coordinates for the FLRW Universe. Then, the quasistatic coordinates are utilized to study the unified first law and the scalar-type perturbations on the cosmological apparent horizon.

  13. An Apparent Paradox: Catt's Anomaly

    Science.gov (United States)

    Pieraccini, M.; Selleri, S.

    2013-01-01

    Catt's anomaly is a sort of "thought experiment" (a "gedankenexperiment") where electrons seem to travel at the speed of light. Although its author argued with conviction for many years, it has a clear and satisfactory solution and it can be considered indubitably just an apparent paradox. Nevertheless, it is curious and…

  14. Children with fever without apparent source: diagnosis and dilemmas

    NARCIS (Netherlands)

    S.E. Bleeker (Sacha)

    2002-01-01

    textabstractTills thesis describes the results of diagnostic research in young children presenting with fever without apparent source at the emergency department. The study was conducted at the Sophia Children's University Hospital in Rotterdam and the Juliana Children's Hospital in The Hague, both

  15. Requirement of the laying hen for apparent fecal digestible lysine

    NARCIS (Netherlands)

    Schutte, J.B.; Smink, W.

    1998-01-01

    A study was conducted to determine the requirement for lysine of a White Leghorn strain of hens with a body weight of approximately 1,600 g. Before starting the experiment, apparent fecal digestibility of amino acids of the basal diet was determined in an in vivo digestibility trial with six individ

  16. Automatic real and apparent age estimation in still images

    OpenAIRE

    Pardo Garcia, Pablo

    2015-01-01

    We performed a study on age estimation via still images creating a new face image database containing real age and apparent age label annotations. Two age estimation methods are proposed using the state of the art techniques and analyse their performance with the proposed database.

  17. A New Theory of Leadership: "Realwert" Versus Apparent Good.

    Science.gov (United States)

    Lang, Donald

    1999-01-01

    "Realwert" ("real good") stems from an understanding of humanity's "raison d'etre"--treating others with respect and dignity. It can be contrasted with "apparent good," a condition wherein one mistakenly thinks real good is being pursued. Drawing on Aquinas and Hodginson, this paper argues for a…

  18. Increasing Range Of Apparent Depth In A Stereoscopic Display

    Science.gov (United States)

    Busquets, Anthony M.; Parrish, Russell V.; Williams, Steven P.

    1995-01-01

    Optical configuration conceived for increasing range of apparent depth provided by stereoscopic display system, without imposing concomitant reduction in field of view. Observer wears shuttered goggles synchronized with alternating left- and right-eye views on display. However, instead of looking directly at display screen, observer looks at screen via reflection in mirror collimating light emitted by screen.

  19. Apparent Barrier Height in Scanning Tunneling Microscopy Revisited

    DEFF Research Database (Denmark)

    Olesen, L.; Brandbyge, Mads; Sørensen, Mads Reinholdt;

    1996-01-01

    The apparent barrier height phi(ap), that is, the rate of change of the logarithm of the conductance with tip-sample separation in a scanning tunneling microscope (STM), has been measured for Ni, Pt, and Au single crystal surfaces. The results show that phi(ap) is constant until point contact...

  20. Fertility and apparent genetic anticipation in Lynch syndrome.

    Science.gov (United States)

    Stupart, Douglas; Win, Aung Ko; Jenkins, Mark; Winship, Ingrid M; Goldberg, Paul; Ramesar, Rajkumar

    2014-09-01

    Genetic anticipation is the phenomenon in which age of onset of an inherited disorder decreases in successive generations. Inconsistent evidence suggests that this occurs in Lynch syndrome. A possible cause for apparent anticipation is fecundity bias, which occurs if the disease adversely affects fertility. The purpose of this study was to determine the effect of age of diagnosis of colorectal cancer (CRC) on lifetime fertility in Lynch syndrome, and whether this can falsely create the appearance of genetic anticipation. A computer model simulated age of diagnosis of CRC in hypothetical Lynch syndrome carriers and their offspring. The model assumed similar age distribution of CRC across generations (i.e. that there was no true anticipation). Age distribution of CRC diagnosis, and lifetime fertility rates (grouped by age of diagnosis of CRC) were determined from the Australasian Colorectal Cancer Family Registry (ACCFR). Apparent anticipation was calculated by comparing ages of diagnosis of CRC in affected parent-child pairs. A total of 1,088 patients with CRC were identified from the ACCFR. Total lifetime (cohort) fertility was related to age of diagnosis of CRC (correlation coefficient 0.13, P = 0.0001). In the simulation, apparent anticipation was 1.8 ± 0.54 years (P = 0.0044). Observed apparent anticipation in the ACCFR cohort was 4.8 ± 1.73 years (P = 0.0064). There was no difference in apparent anticipation between the simulate d and observed parent-child pairs (P = 0.89). The appearance of genetic anticipation in Lynch syndrome can be falsely created due to changes in fertility.

  1. Volume inside old black holes

    Science.gov (United States)

    Christodoulou, Marios; De Lorenzo, Tommaso

    2016-11-01

    Black holes that have nearly evaporated are often thought of as small objects, due to their tiny exterior area. However, the horizon bounds large spacelike hypersurfaces. A compelling geometric perspective on the evolution of the interior geometry was recently shown to be provided by a generally covariant definition of the volume inside a black hole using maximal surfaces. In this article, we expand on previous results and show that finding the maximal surfaces in an arbitrary spherically symmetric spacetime is equivalent to a 1 +1 geodesic problem. We then study the effect of Hawking radiation on the volume by computing the volume of maximal surfaces inside the apparent horizon of an evaporating black hole as a function of time at infinity: while the area is shrinking, the volume of these surfaces grows monotonically with advanced time, up to when the horizon has reached Planckian dimensions. The physical relevance of these results for the information paradox and the remnant scenarios are discussed.

  2. Apparent Dissolution Kinetics of Diatomite in Alkaline Solution

    Institute of Scientific and Technical Information of China (English)

    DU Gaoxiang; L(U) Guocheng; HE Xuwen

    2013-01-01

    The dissolution kinetics of diatomite in alkaline solution is the theoretical basis for the process optimization of alkali-diatomite reaction and its applications.In this study,the dissolution kinetics of diatomite in NaOH solution is investigated.The results indicate that the dissolution reaction fits well the unreacted shrinking core model for solid-liquid heterogeneous reactions.The apparent reaction order for NaOH is 2 and the apparent activation energy for the reaction (Ea) is 28.06 kJ.mol-1.The intra-particle diffusion through the sodium silicate layer is the rate-controlling step.When the dissolution reaction occurs at the interface of unreacted diatomite solid core,the diffusion in the trans-layer (the liquid film around the wetted particle) reduces the rate of whole dissolution process.

  3. Mass density at geostationary orbit and apparent mass refilling

    Science.gov (United States)

    Denton, R. E.; Takahashi, Kazue; Amoh, Justice; Singer, H. J.

    2016-04-01

    We used the inferred equatorial mass density ρm,eq based on measurements of Alfvén wave frequencies measured by the GOES satellites during 1980-1991 in order to construct a number of different models of varying complexity for the equatorial mass density at geostationary orbit. The most complicated models are able to account for 66% of the variance with a typical variation from actual values of a factor of 1.56. The factors that influenced ρm,eq in the models were, in order of decreasing importance, the F10.7 EUV index, magnetic local time, the solar wind dynamic pressure Pdyn, the phase of the year, and the solar wind BZ (GSM Z direction). During some intervals, some of which were especially geomagnetically quiet, ρm,eq rose to values that were significantly higher than those predicted by our models. For 10 especially quiet intervals, we examined long-term (>1 day) apparent refilling, the increase in ρm,eq at a fixed location. We found that the behavior of ρm,eq varies for different events. In some cases, there is significant apparent refilling, whereas in other cases ρm,eq stays the same or even decreases slightly. Nevertheless, we showed that on average, ρm,eq increases exponentially during quiet intervals. There is variation of apparent refilling with respect to the phase of the solar cycle. On the third day of apparent refilling, ρm,eq has on average a similar value at solar maximum or solar minimum, but at solar maximum, ρm,eq begins with a larger value and rises relatively less than at solar minimum.

  4. Lead-Free Metamaterials with Enormous Apparent Piezoelectric Response.

    Science.gov (United States)

    Zhou, Wanfeng; Chen, Pan; Pan, Qi; Zhang, Xiaotong; Chu, Baojin

    2015-11-01

    Lead-free flexoelectric piezoelectric metamaterials are created by applying an asymmetric chemical reduction to Na1/2 Bi1/2 TiO3 -BaTiO3 ceramics. The reduction induces two gradient-generating mechanisms, curvature structure and chemical inhomogeneity, and enhances the flexoelectric effect. The ceramics behave like piezoelectric materials, exhibiting an enormous and high-temperature stable apparent piezoelectric response, outperforming existing lead-oxide-based piezoelectrics.

  5. Definition of apparent activation energy on DTG curves

    Directory of Open Access Journals (Sweden)

    A. K. Serikbayeva

    2016-07-01

    Full Text Available The article gives the results of sulphidation oxidized copper ores and tailings with sulfur. Defined by the apparent activation energy in the conditions of heating the mixture of substances interacting with a constant speed by differential thermogravimetry (DTG. It was established that the sulfiding may occur in a kinetic mode , since the interaction is charged, in the presence of liquid and gaseous sulfur , i.e. transport of sulfur to the surface of the mineral is not a limiting process.

  6. Definition of apparent activation energy on DTG curves

    OpenAIRE

    Serikbayeva, A. K.; Zhumashev, K.; N. Sh. Janaliyeva; M. Rakhimberdina

    2016-01-01

    The article gives the results of sulphidation oxidized copper ores and tailings with sulfur. Defined by the apparent activation energy in the conditions of heating the mixture of substances interacting with a constant speed by differential thermogravimetry (DTG). It was established that the sulfiding may occur in a kinetic mode , since the interaction is charged, in the presence of liquid and gaseous sulfur , i.e. transport of sulfur to the surface of the mineral is not a limiting process.

  7. Product design enhancement using apparent usability and affective quality.

    Science.gov (United States)

    Seva, Rosemary R; Gosiaco, Katherine Grace T; Santos, Ma Crea Eurice D; Pangilinan, Denise Mae L

    2011-03-01

    In this study, apparent usability and affective quality were integrated in a design framework called the Usability Perception and Emotion Enhancement Model (UPEEM). The UPEEM was validated using structural equation modeling (SEM). The methodology consists of four phases namely product selection, attribute identification, design alternative generation, and design alternative evaluation. The first stage involved the selection of a product that highly involves the consumer. In the attribute identification stage, design elements of the product were identified. The possible values of these elements were also determined for use in the experimentation process. Design of experiments was used to identify how the attributes will be varied in the design alternative stage and which of the attributes significantly contribute to affective quality, apparent usability, and desirability in the design evaluation stage. Results suggest that product attributes related to form are relevant in eliciting intense affect and perception of usability in mobile phones especially those directly related to functionality and aesthetics. This study considered only four product attributes among so many due to the constraints of the research design employed. Attributes related to aesthetic perception of a product enhance apparent usability such as those related to dimensional ratios.

  8. Coherent and random apparent stresses in periodically unsteady flows

    Science.gov (United States)

    Kehoe, Anthony Byrd

    1990-08-01

    The transitional flow field downstream of a smooth, symmetrically constricted Sylgard pipe was measured with a two color, two component Laser Doppler Anemometer for both pulsatile and steady flows. Vibrations in the flow system were induced with an exciter/shaker and were monitored with an accelerator. The vibration has little effect on the value of the maximum axial and radial turbulence intensities. A frequency domain signal processing technique to separate the disturbance velocity into coherent and random components was modified to guarantee that the sum of the decomposed velocity components equaled the original disturbance velocity. Results of the velocity separation demonstrated that the velocity disturbances prior to turbulent transition consisted almost entirely of coherent velocity fluctuations. The maximum apparent shear stress was found to occur just after the turbulent transition and consisted almost entirely of the random component. The data suggest that if the absolute magnitude of the apparent stress is the determining factor in red blood cell destruction, then the coherent apparent stress is not a significant destruction mechanism. However, the exact mechanism in hemolysis are not identified.

  9. The apparent state of droplets on a rough surface

    Institute of Scientific and Technical Information of China (English)

    CHEN XiaoLing; LU Tian

    2009-01-01

    The factors influencing the state and wetting transition of droplets on a rough surface are both complex and obscure. The change in wetting is directly reflected by changes under the contact condition of the droplets with the surface. The recent study about the wettability of the superhydrophobic surface under the condensing condition arouses the new understanding about the apparent state of droplets on a rough surface, in this work, to validate the existence of droplets in an intermediate state, a microscale pillar topological polydimethylsiloxane (PDMS) surface was manufactured and its wettability under various conditions was studied. According to the experimental data, it is proposed that the wetting state of a rough surface may be embodied using the contact area ratio of a solid/liquid/gas droplet with the projective plane. A general calculation model for the apparent contact angle of droplets is given and expressed diagrammatically. It is found that the measured apparent contact angles of droplets at dif-ferent states on the surface falls within the range predicted by our proposed equation.

  10. Apparent kinetics of high temperature oxidative decomposition of microalgal biomass.

    Science.gov (United States)

    Ali, Saad Aldin M; Razzak, Shaikh A; Hossain, Mohammad M

    2015-01-01

    The oxidative thermal characteristics of two microalgae species biomass Nannochloropsis oculta and Chlorella vulgaris have been investigated. The apparent kinetic parameters for the microalgal biomass oxidation process are estimated by fitting the experimental data to the nth order rate model. Also, the iso-conversional methods Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO) were used to evaluate the apparent activation energy. The results indicate that biomass of different microalgae strains exhibit different thermal behavior and characteristics. In addition, growth parameters and medium composition can affect the biomass productivity and composition. This would have significant impact on the thermal decomposition trend of the biomass. The kinetic modeling of the oxidation reaction with direct model fitting method shows good prediction to the experimental data. The apparent activation energies estimated by KAS and FWO methods for N. oculta were 149.2 and 151.8kJ/mol, respectively, while for C. vulgaris were 214.4 and 213.4kJ/mol, respectively.

  11. The apparent state of droplets on a rough surface

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The factors influencing the state and wetting transition of droplets on a rough surface are both complex and obscure. The change in wetting is directly reflected by changes under the contact condition of the droplets with the surface. The recent study about the wettability of the superhydrophobic surface under the condensing condition arouses the new understanding about the apparent state of droplets on a rough surface. In this work, to validate the existence of droplets in an intermediate state, a microscale pillar topological polydimethylsiloxane (PDMS) surface was manufactured and its wettability under various conditions was studied. According to the experimental data, it is proposed that the wetting state of a rough surface may be embodied using the contact area ratio of a solid/liquid/gas droplet with the projective plane. A general calculation model for the apparent contact angle of droplets is given and expressed diagrammatically. It is found that the measured apparent contact angles of droplets at dif- ferent states on the surface falls within the range predicted by our proposed equation.

  12. A discrete model for the apparent viscosity of polydisperse suspensions including maximum packing fraction

    CERN Document Server

    Dörr, Aaron; Mehdizadeh, Amirfarhang

    2012-01-01

    Based on the notion of a construction process consisting of the stepwise addition of particles to the pure fluid, a discrete model for the apparent viscosity as well as for the maximum packing fraction of polydisperse suspensions of spherical, non-colloidal particles is derived. The model connects the approaches by Bruggeman and Farris and is valid for large size ratios of consecutive particle classes during the construction process. Furthermore, a new general form of the well-known Krieger equation allowing for the choice of a second-order Taylor coefficient for the volume fraction is proposed and then applied as a monodisperse reference equation in the course of polydisperse modeling. By applying the polydisperse viscosity model to two different particle size distributions (Rosin-Rammler and uniform distribution), the influence of polydispersity on the apparent viscosity is examined. The extension of the model to the case of small size ratios as well as to the inclusion of shear rate effects is left for fut...

  13. Ultrasonic backscatter from cancellous bone: the apparent backscatter transfer function.

    Science.gov (United States)

    Hoffmeister, Brent K; Mcpherson, Joseph A; Smathers, Morgan R; Spinolo, P Luke; Sellers, Mark E

    2015-12-01

    Ultrasonic backscatter techniques are being developed to detect changes in cancellous bone caused by osteoporosis. Many techniques are based on measurements of the apparent backscatter transfer function (ABTF), which represents the backscattered power from bone corrected for the frequency response of the measurement system. The ABTF is determined from a portion of the backscatter signal selected by an analysis gate of width τw delayed by an amount τd from the start of the signal. The goal of this study was to characterize the ABTF for a wide range of gate delays (1 μs ≤ τd ≤ 6 μs) and gate widths (1 μs ≤ τw ≤ 6 μs). Measurements were performed on 29 specimens of human cancellous bone in the frequency range 1.5 to 6.0 MHz using a broadband 5-MHz transducer. The ABTF was found to be an approximately linear function of frequency for most choices of τd and τw. Changes in τd and τw caused the frequency-averaged ABTF [quantified by apparent integrated backscatter (AIB)] and the frequency dependence of the ABTF [quantified by frequency slope of apparent backscatter (FSAB)] to change by as much as 24.6 dB and 6.7 dB/MHz, respectively. τd strongly influenced the measured values of AIB and FSAB and the correlation of AIB with bone density (-0.95 ≤ R ≤ +0.68). The correlation of FSAB with bone density was influenced less strongly by τd (-0.97 ≤ R ≤ -0.87). τw had a weaker influence than τd on the measured values of AIB and FSAB and the correlation of these parameters with bone density.

  14. Apparent faster than light propagation from light sterile neutrinos

    CERN Document Server

    Hannestad, Steen

    2011-01-01

    Recent data from the OPERA experiment seem to point to neutrinos propagating faster than light. One possible physics explanation for such a result is the existence of light sterile neutrinos which can propagate in a higher dimensional bulk and achieve apparent superluminal velocities when measured by an observer confined to the 4D brane of the standard model. Such a model has the advantage of easily being able to explain the non-observation of superluminal neutrinos from SN1987A. Here we discuss the phenomenological implications of such a model and show that it can provide an explanation for the observed faster than light propagation of neutrinos.

  15. Study on Apparent Viscosity and Structure of Foaming Slag

    Science.gov (United States)

    Martinsson, Johan; Glaser, Björn; Sichen, Du

    2016-10-01

    Foaming slag was generated using induction heating. The foam was found non-Newtonian having much higher apparent viscosity compared to the dynamic viscosity of pure slag. Quenched foam was examined. The appearance of the foaming slag was very different from silicone oil-gas foam. The size of gas bubbles ranged from 0.1 to 4 mm (while in the case of silicone oil, 1 to 2 mm). The gas fraction in the foam was considerably lower than in the case of silicone oil.

  16. Solutions of the Einstein Constraint Equations with Apparent Horizon Boundary

    CERN Document Server

    Maxwell, D

    2003-01-01

    We construct asymptotically Euclidean solutions of the vacuum Einstein constraint equations with apparent horizon boundary condition. Specifically, we give sufficient conditions for the constant mean curvature conformal method to generate such solutions. The method of proof is based on the barrier method introduced by Isenberg for compact manifolds without boundary, suitably extended to accommodate semilinear boundary conditions and low regularity metrics. As a consequence of our results for manifolds with boundary, we also obtain improvements to the theory of the constraint equations on asymptotically Euclidean manifolds without boundary.

  17. Apparent Coulomb reacceleration of neutrons in electrodissociation of the deuteron

    Energy Technology Data Exchange (ETDEWEB)

    Bianconi, A.; Jeschonnek, S.; Nikolaev, N.N.; Zakharov, B.G. (Istituto Nazionale di Fisica Nucleare, Sezione di Pavia, Pavia (Italy) Dipartimento Fisica Nucleare e Teorica, Universita di Pavia (Italy) IKP (Theorie), Forschungszentrum Juelich GmbH., D-52425 Juelich (Germany) L. D. Landau Institute for Theoretical Physics, GSP-1, 117940, ul.-Kosygina 2, V-334 Moscow (Russian Federation))

    1995-03-01

    We demonstrate that the final state [ital p]-[ital n] interaction in the reaction of electrodissociation of the deuteron at large [ital Q][sup 2] in a static external field leads to the apparent reacceleration of neutrons. The shift of the neutron velocity from the velocity of the deuteron beam is related to the quantum-mechanical forward-backward asymmetry of the missing momentum distribution in the [sup 2]H ([ital e],[ital e][prime][ital p])[ital n] scattering.

  18. Mechanical Components from Highly Recoverable, Low Apparent Modulus Materials

    Science.gov (United States)

    Padula, Santo, II (Inventor); Noebe, Ronald D. (Inventor); Stanford, Malcolm K. (Inventor); DellaCorte, Christopher (Inventor)

    2015-01-01

    A material for use as a mechanical component is formed of a superelastic intermetallic material having a low apparent modulus and a high hardness. The superelastic intermetallic material is conditioned to be dimensionally stable, devoid of any shape memory effect and have a stable superelastic response without irrecoverable deformation while exhibiting strains of at least 3%. The method of conditioning the superelastic intermetallic material is described. Another embodiment relates to lightweight materials known as ordered intermetallics that perform well in sliding wear applications using conventional liquid lubricants and are therefore suitable for resilient, high performance mechanical components such as gears and bearings.

  19. Discovery of an Apparent Nova in M81

    Science.gov (United States)

    Hornoch, K.; Vaduvescu, O.; Gonzalez, A.

    2013-04-01

    We report the discovery of an apparent nova in the M81 galaxy on a co-added 2000-s narrow-band H-alpha CCD image taken with the 2.5-m Isaac Newton Telescope (INT) + WFC at La Palma in ~1.4" seeing on Apr. 5.946 UT. The new object is visible on individual 400-s frames and well visible on the co-added image (see the finding chart linked below), but is not present on numerous narrow-band H-alpha archival images from the INT down to limiting magnitude as faint as H-alpha = 21.7.

  20. A Case of Apparent Contact Dermatitis Caused by Toxocara Infection

    Directory of Open Access Journals (Sweden)

    Rosanna Qualizza

    2014-01-01

    Full Text Available Infection from Toxocara species may give rise to a large array of clinical symptoms, including apparent manifestations of allergy such as asthma, urticaria/angioedema, and dermatitis. We report a case, thus far not described, of contact dermatitis attributed to nickel allergy but caused by Toxocara infection. The patient was a 53-year-old woman presenting from 10 years a dermatitis affecting head, neck, and thorax. Patch tests initially performed gave a positive result to nickel, but avoidance of contact with nickel did not result in recovery. The patient referred to our Allergy Service in 2010 because of dermatitis to feet. Patch testing confirmed the positive result for nickel, but expanding the investigation a positive result for IgG antibodies to Toxocara was detected by Western blotting and ELISA. Treatment with mebendazole achieved immediate efficacy on feet dermatitis. Then, two courses of treatment with albendazole resulted in complete regression of dermatitis accompanied by development of negative ELISA and Western blotting for Toxocara antibodies. This report adds another misleading presentation of Toxocara infection as apparent contact dermatitis caused by nickel and suggests bearing in mind, in cases of contact dermatitis not responding to avoidance of the responsible hapten and to medical treatment, the possible causative role of Toxocara.

  1. Apparent nitrogen digestibility data: AACC-ASTM collaborative study.

    Science.gov (United States)

    Happich, M L; Bodwell, C E; Hackler, L R; Phillips, J G; Derse, P H; Elliott, J G; Hopkins, D T; Parsons, G F; Prescher, E E; Robaidek, E S

    1984-01-01

    Apparent nitrogen digestibility data were obtained from 4 laboratories for 6 protein sources and 2 diet levels, 6 and 10% protein, after a 2-day adaptation period during the AACC-ASTM protein efficiency ratio (PER) and net protein ratio (NPR) collaborative studies. For 5 protein sources fed as 10% of the diet, the interlaboratory variation as measured by coefficient of variation (CV) values was low (1.5-3.5%), indicating high precision of the method. Wheat flour (6% protein diet) had the highest variation and, therefore, the lowest precision (CV of 7.10%). The interlaboratory variation (CV value) for 3 of the 4 laboratories was considerably lower, less than half that for the 4 laboratories. An analysis of variance of apparent nitrogen digestibility data indicated significant (P less than 0.05) effects for the 4-laboratory group due to laboratories and protein diets at both 10 and 6% protein levels, and for the 3-laboratory group at the 10% protein level. The 3-laboratory ANOVA for the 6% diets indicated a significant effect (P less than 0.05) due to diet only.

  2. The hidden face of Kanizsa's triangle: apparent movement of subjective figures in three-dimensional space.

    Science.gov (United States)

    Vallortigara, G

    1987-01-01

    Several demonstrations on the apparent movement in depth of subjective figures are presented. They include: (a) apparent rotational movement as a result of shape invariance or rigidity; (b) apparent rotational movement with three-dimensional subjective figures not accompanied by a brightness gradient; and (c) apparent rotational movement by kinetic occlusion.

  3. Energy Dissipation and Apparent Viscosity of Semi-solid Metal during Rheological Processes Part Ⅱ: Apparent Viscosity

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    This study investigated the rheological properties of semi-solid metal. An analytical model of apparent viscosity was built up based on analysis of energy dissipation during rheological processes such as slurry preparing,delivering and model filling. The rheological properties of SSM (semi-solid metal) slurry was described by an analytical model in terms of microstructural parameters, which consist of effective solid fraction, particle size and shape, and flow parameters such as mean velocity, fluctuant velocity and relative velocity between liquid and solid phase. The model was verified in the experiment of A356 alloys with a coaxial double-bucket rheometer. And the maximum relative error between the theoretical value and measured one is less than 10%.The results of experiment and theoretical calculation also indicate that the microstructural parameters and flow parameters are two major factors that affect the apparent viscosity of semi-solid alloys, and fluctuant velocity and relative velocity between liquid and solid phase are the key factors to distinguish between steady and transient rheological properties.

  4. Galvanic apparent internal impedance: an intrinsic tissue property.

    Science.gov (United States)

    Golberg, Alex; Rabinowitch, Haim D; Rubinsky, Boris

    2009-11-01

    Using basic galvanic cell principles, the ability of tissues to generate electrical current through electrolysis was characterized. Studying Zn/Cu electrolysis in animal organs revealed a fundamental and measurable tissue-specific property - the galvanic apparent internal impedance (GAII), that is most likely related to the salt bridge function of tissues delineated by electrodes. Further to the fundamental knowledge acquired, GAII enables a new diagnostic method to distinguish between tissue types and to determine their health status without a need for expensive calibration, as often required when external power source is used. We demonstrated the GAII sensitivity in detecting tissue ablation with microwave heating or irreversible electroporation. The results open the way for a novel, inexpensive self-powered tissue diagnostic system for a wide range of applications such as minimally invasive tissue health status, ischemia, hydration, real time intra-operative control of minimally invasive surgery, medical imaging, virtual biopsy and many others.

  5. A "fair sampling" perspective on an apparent violation of duality

    CERN Document Server

    Bolduc, Eliot; Miatto, Filippo M; Leuchs, Gerd; Boyd, Robert W

    2014-01-01

    In the event in which a quantum mechanical particle can pass from an initial state to a final state along two possible paths, the duality principle states that "the simultaneous observation of wave and particle behavior is prohibited". [M. O. Scully, B.-G. Englert, and H. Walther. Nature, 351:111-116, 1991.] emphasized the importance of additional degrees of freedom in the context of complementarity. In this paper, we show how the consequences of duality change when allowing for biased sampling, that is, postselected measurements on specific degrees of freedom of the environment of the two-path state. Our work contributes to the explanation of previous experimental apparent violations of duality [R. Menzel, D. Puhlmann, A. Heuer, and W. P. Schleich. Proc. Natl. Acad. Sci., 109(24):9314-9319, 2012.] and opens up the way for novel experimental tests of duality.

  6. Vitrectomy for bilateral macular schisis without apparent optic disc anomalies

    Science.gov (United States)

    Andonegui, José; Maya, José Ramón; Echeverría, Marta; Alcaine, Araceli

    2016-01-01

    A 78-year-old man complained of bilateral visual acuity loss. Optical coherence tomography examination showed bilateral macular schisis with fluid accumulation in the external retinal layers without vitreous traction. Fundus examination and fluorescein angiography were normal in both eyes. Both eyes were treated by phacoemulsification, intraocular lens implantation, and vitrectomy without laser, gas exchange, or retinal fenestration. Slow and progressive fluid resorption and improvement in VA were observed in both eyes. Macular schisis similar to the one associated with optic disc anomalies is a possibility in patients without apparent disc anomalies. Vitrectomy without laser, gas, or retinal fenestration may be a good therapeutic option even in patients with a PVD preoperatively. PMID:27703873

  7. Plant-mediated 'apparent effects' between mycorrhiza and insect herbivores.

    Science.gov (United States)

    Gilbert, Lucy; Johnson, David

    2015-08-01

    Plants mediate indirect 'apparent' effects between above-ground herbivores and below-ground mutualistic mycorrhizal fungi. The herbivore-plant-mycorrhiza continuum is further complicated because signals produced by plants in response to herbivores can be transmitted to other plants via shared fungal networks below ground. Insect herbivores, such as aphids, probably affect the functioning of mycorrhizal fungi by changing the supply of recent photosynthate from plants to mycorrhizas, whereas there is evidence that mycorrhizas affect aphid fitness by changing plant signalling pathways, rather than only through improved nutrition. New knowledge of the transfer of signals through fungal networks between plant species means we now need a better understanding of how this process occurs in relation to the feeding preferences of herbivores to shape plant community composition and herbivore behaviour in nature.

  8. Apparent motion perception in patients with paranoid schizophrenia.

    Science.gov (United States)

    Sanders, Lia Lira Olivier; de Millas, Walter; Heinz, Andreas; Kathmann, Norbert; Sterzer, Philipp

    2013-04-01

    Impaired perceptual inference has been suggested to be at the core of positive symptoms in schizophrenia. Apparent motion (AM) is a visual illusion in which perceptual inference gives rise to the experience of a single object moving back and forth when two spatially separated objects are flashed in alternation. Here, we investigated the strength of AM perception in patients with paranoid schizophrenia. Patients were less susceptible to the illusion as indicated by a lower probability of motion perception at the individual's optimal presentation frequency for AM. In addition, the probability of AM perception was inversely related to delusional conviction in the patient group. These results suggest that schizophrenia may be associated with a reduced susceptibility to visual phenomena that commonly rely on perceptual inference.

  9. Determination of apparent sampling thickness of sea surface microlayer

    Science.gov (United States)

    Li, Jun; Ding, Hai-Bing; Wu, Zhi-Jian; Zhang, Zheng-Bin; Liu, Lian-Sheng

    1998-06-01

    In situ and laboratory studies of sea—surface microlayer sampling methods using glass plate, rotating drum, screen and funnel samplers were conducted. For glass plate and rotating drum samplers, surface microlayer samples of different thickness were collected by controlling their withdrawal rate and rotating rate. The relationships between pH, surface tension, the concentration of dissolved trace metals Cu and Pb, phosphate, particulate matters and sampling thickness were carefully investigated. It was shown that physicochemical and biological properties change obviously at the sampling thickness of about 50 μm, which is consistent with the mean thickness of the boundary film in the models of gas exchange across the sea surface. It is proposed that the apparent sampling thickness of the surface microlayer should be less than 40 μm. The factors affecting the sampling thickness are discussed, and the feasibility and applicable conditions for different sampling methods are evaluated.

  10. When luminance increment thresholds depend on apparent lightness.

    Science.gov (United States)

    Maertens, Marianne; Wichmann, Felix A

    2013-05-31

    A fundamental question in visual perception research is whether the sensitivity to stimulus differences is limited by the sensory representation of the external stimulus, that is, the proximal stimulus, or by its perceptual representation, i.e., stimulus appearance. In the domain of lightness perception, the question translates into whether discrimination thresholds depend on the local luminance in the retinal image or on the apparent lightness of the corresponding image region. The majority of findings seem to indicate that sensitivity is limited by the sensory stimulus representation, which would imply different mechanisms for stimulus discrimination and appearance. We think this conclusion needs to be qualified. We report data suggesting that the relationship between discrimination and appearance judgments depends on how exactly they are being measured. We propose a theoretical account that provides a common mechanism for appearance and sensitivity. An interesting corollary of this model is that it also accounts for the perceptual phenomenon of assimilation.

  11. Contribution of Chlorophyll Fluorescence to the Apparent Reflectance of Vegetation

    Science.gov (United States)

    Campbell, P. K. Entcheva; Middleton, E. M.; Kim, M. S.

    2007-01-01

    Current strategies for monitoring the physiologic status of terrestrial vegetation rely on remote sensing reflectance (R) measurements, whi ch provide estimates of relative vegetation vigor based primarily on chlorophyll content. Vegetation chlorophyll fluorescence (CF) offers a non-destructive alternative and a more direct approach for diagnosis of vegetation stress before a significant reduction in chlorophyll content has occurred. Thus, monitoring of vegetation vigor based on CF may allow earlier stress detection and more accurate carbon sequestra tion estimates, than is possible using R data alone. However, the observed apparent vegetation reflectance (Ra) in reality includes contrib utions from both the reflected and fluoresced radiation. The aim of t his study is to determine the relative R and CF fractions contributing to Ra from the vegetation in the red to near-infrared region of the spectrum. The practical objectives of the study are to: 1) evaluate t he relationship between CF and R at the foliar level for corn, soybean, maple; and 2) for corn, determine if the relationship established f or healthy (optimal N) vegetation changes under N defiiency. To obtai n generally applicable results, experimental measurements were conducted on unrelated crop and tree species (maple, soybean and corn), unde r controlled conditions and a gradient of inorganic N fertilization l evels. Optical R spectra and actively induced CF emissions were obtained on the same foliar samples, in conjunction with measurements of p hotosynthetic function, pigment levels, and C and N content. The comm on spectral trends or similarities were examined. On average, 10-20% of apparent R at 685 nm was actually due to CF. The spectral trends in steady and maximum F varied significantly, with Fs (especially red) showing higher ability for species and treatment separation. The relative contribution of ChF to R varied significantly among species, with maple emitting much higher F amounts, as

  12. Age- and direction-related adaptations of lumbar vertebral trabecular bone with respect to apparent stiffness and tissue level stress distribution

    Institute of Scientific and Technical Information of China (English)

    He Gong; Yubo Fan; Ming Zhang; Ling Qin

    2009-01-01

    The objective of this study was to study the age-related adaptation of lumbar vertebral trabecular bone at the apparent level, as well as the tissue level in three orthog-onal directions. Ninety trabecular specimens were obtained from six normal L4 vertebral bodies of six male cadavers in two age groups, three aged 62 years and three aged 69 years, and were scanned using a high-resolution micro-computed tomography (micro-CT) system, then converted to micro-finite element models to do micro-finite element analyses. The relationship between apparent stiffness and bone volume fraction, and the tissue level von Mises stress distribution for each trabecular specimen when compressed separately in the longitudinal direction, medial-lateral and anterior-posterior directions (transverse directions) were derived and compared between two age groups. The results showed that at the appar-ent level, trabecular bones from 69-year group had stiffer bone structure relative to their volume fractions in all three directions, and in both age groups, changes in bone volume fraction could explain more variations in apparent stiffness in the longitudinal direction than the transverse directions; at the tissue level, aging had little effect on the tissue von Mises stress distributions for the compressions in all the three directions. The novelty of the present study was that it provided quantitative assessments on the age and direction-related adaptation of Chinese male lumbar vertebral trabec-ular bone from two different levels: stiffness at the apparent level and stress distribution at the tissue level. It may help to understand the failure mechanisms and fracture risks of vertebral body associated with aging and direction for the prevention of fracture risks in elder individuals.

  13. Knoop Hardness - Apparent Yield Stress Relationship in Ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Swab, Jeffrey J [ORNL; LaSalvia, Jerry [U.S. Army research Laboratory, Adelphi, MD; Wereszczak, Andrew A [ORNL; Strong, Kevin T [ORNL; Danna, Dominic [U.S. Army research Laboratory, Adelphi, MD; Ragan, Meredith E [ORNL; Ritt, Patrick J [ORNL

    2012-01-01

    In Tabor's classical studies of the deformation of metals, the yield stress (Y) and hardness (H) were shown to be related according to H/Y {approx} 3 for complete or fully plastic deformation. Since then it has been anecdotally shown for ceramics that this ratio is <3. Interest exists to explore this further so Hertzian indentation was used to measure the apparent yield stress of numerous ceramics and metals and their results were compared with each material's load-dependent Knoop hardness. The evaluated ceramics included standard reference materials for hardness (silicon nitride and tungsten carbide), silicon carbide, alumina, and glass. Several steel compositions were also tested for comparison. Knoop hardness measurements at 19.6 N (i.e., toward 'complete or fully plastic deformation'), showed that 2 < H/Y < 3 for the metals and 0.8 < H/Y < 1.8 for the glasses and ceramics. Being that H/Y {ne} 3 for the ceramics indicates that Tabor's analysis is either not applicable to ceramics or that full plastic deformation is not achieved with a Knoop indentation or both.

  14. Mixed quotation: The grammar of apparently transparent opacity

    Directory of Open Access Journals (Sweden)

    Emar Maier

    2014-05-01

    Full Text Available The phenomenon of mixed quotation exhibits clear signs of both the apparent transparency of compositional language use and the opacity of pure quotation. I argue that the interpretation of a mixed quotation in- volves the resolution of a metalinguistic presupposition. The leading idea behind my proposal is that a mixed-quoted expression, say, “has an anomalous feature”, means what x referred to with the words ‘has an anomalous feature’. To understand how this solves the paradox, I set up a precise grammatical framework, explicitly connecting various levels of linguistic analysis: phonological forms, categorial syntax, and a dynamic picture of the semantics–pragmatics interface. In this framework I formalize and evaluate a presuppositional account of mixed quotation. Finally, I address the phenomenon of unquotation and argue that it is an essential ingredient for an elegant and empirically adequate analysis of mixed quotation in natural language. http://dx.doi.org/10.3765/sp.7.7 BibTeX info

  15. Nephrotic Syndrome and Acute Renal Failure Apparently Induced by Sunitinib

    Directory of Open Access Journals (Sweden)

    Ying-Shou Chen

    2009-10-01

    Full Text Available We report a case of nephrotic syndrome and acute renal failure apparently induced by sunitinib. A 67-year-old man with a history of metastatic renal cell carcinoma presented with progressive kidney dysfunction with proteinuria, general edema, and body weight gain of 21 kg after undergoing 3 weeks of sunitinib therapy. The patient had taken no other over-the-counter medications, and all other possible causes of nephrotic syndrome were excluded. The Naranjo Adverse Drug Reaction Probability Scale score for this event was 6, indicating a high probability that the observed presentations were associated with use of the drug. However, despite the discontinuation of sunitinib, his condition deteriorated, and hemodialysis was initiated for respiratory distress. A renal biopsy was performed, which revealed ischemic acute tubular necrosis with minimal change nephropathy. In conclusion, nephrologists and oncologists should be aware that nephrotic syndrome with ischemic acute tubular necrosis is a possible adverse effect of sunitinib. For early diagnosis of this condition and to avoid renal damage, we recommend differential diagnosis of serum creatinine and proteinuria in patients undergoing sunitinib therapy.

  16. Estimating phosphorus concentrations following alum treatment using apparent settling velocity

    Science.gov (United States)

    Panuska, John; Robertson, Dale M.

    2009-01-01

    he apparent settling velocity (Vs) is a term used in empirical, steady-state, mass-balance lake models to represent the net phosphorus flux from the water column. The Vollenweider (1969) mixed-reactor lake model was rearranged and used to calculate Vs values for total phosphorus (TP) for three lakes treated with alum to reduce the internal flux of P to the water column (Delavan Lake, Wisconsin; Lake Morey, Vermont; and West Twin Lake, Ohio). An analysis of Vs values was conducted using data from these three lakes for both the pre- and post-alum treated conditions. Analysis of Vs values for both the pre- and post-alum conditions in Lake Morey and West Twin Lake resulted in a post-treatment mean Vs value of 7 ± 2.0 m·yr−1. The effect of the alum treatment, although short-lived in Delavan Lake, resulted in a mean post-treatment Vs value of 3.4 ± 0.3 m·yr−1. The consistency in the post-treatment Vs values in Lake Morey and West Twin Lake is used to demonstrate a predictive analysis method for water column TP concentrations in lakes following a successful treatment of the anoxic sediment area with alum. Additional pre- and post-alum in-lake and watershed loading data are needed to advance this concept into a management model.

  17. Two Qatari siblings with cystic fibrosis and apparent mineralocorticoid excess

    Directory of Open Access Journals (Sweden)

    Khalid Zahraldin

    2015-01-01

    Full Text Available Cystic fibrosis (CF and apparent mineralocorticoid excess (AME syndrome are both autosomal recessive disorders that result from mutations of specific identified genes for each condition. CF is caused by defects in the Cystic fibrosis trans membrane conductance regulator (CFTR gene which encodes for a protein that functions as a chloride channel and regulates the flow of other ions across the apical surface of epithelial cells. AME is due to the deficiency of 11β-hydroxysteroid dehydrogenase type 2 enzyme (11βHSD2, which is responsible for the peripheral inactivation of cortisol to cortisone. Cortisol excess stimulates the mineralocoritoid receptors (MR resulting in intense sodium retention, hypokalemia and hypertension. We report on a consanguineous Arab family, in which two sibs inherited both CF and AME. Gene testing for AME revealed previously unreported mutation in the 11βHSD2 gene. This report draws attention to the importance of recognizing the possibility of two recessive disorders in the same child in complex consanguineous families. Moreover, it provides a unique opportunity to highlight the implications of the coexistence of two genetic disorders on patient care and genetic counseling of the family.

  18. Microlensing optical depth as a function of source apparent magnitude

    CERN Document Server

    Wood, Alexander

    2007-01-01

    Measurements of the microlensing optical depth, tau, towards the Galactic bulge appear to depend on the method used to obtain them. Those values based on the lensing of red clump giants (RCGs) appear to be significantly lower than those based on the lensing of all stars along the line of sight. This discrepancy is still not understood. Through Monte Carlo simulations, it is found that the discrepancy cannot be explained by a dependance on the flux limits of the two methods. The optical depth is expected to be generally constant as a function of source apparent magnitude for I_0 >~ 13.0, except in the range 13.5 <~ I_0 <~ 15.5. Here many RCGs are detected, causing a significant oscillation in tau. The amplitude of this oscillation is a function of the inclination angle of the Galactic bar, theta_bar, which may thus be constrained. A further constraint comes from a similar dependance of tau with theta_bar: combining the predicted trends with the measured values provides 1-sigma upper limits, which exclude...

  19. Site Environmental Report for 2009, Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Suying

    2010-08-19

    Volume II of the Site Environmental Report for 2009 is provided by Ernest Orlando Lawrence Berkeley National Laboratory as a supplemental appendix to Volume I, which contains the body of the report. Volume II contains the environmental monitoring and sampling data used to generate summary results of routine and nonroutine sampling at the Laboratory, except for groundwater sampling data, which may be found in the reports referred to in Chapter 4 of Volume I. The results from sample collections are more comprehensive in Volume II than in Volume I: for completeness, all results from sample collections that began or ended in calendar year (CY) 2009 are included in this volume. However, the samples representing CY 2008 data have not been used in the summary results that are reported in Volume I. (For example, although ambient air samples collected on January 6, 2009, are presented in Volume II, they represent December 2008 data and are not included in Table 4-2 in Volume I.) When appropriate, sampling results are reported in both conventional and International System (SI) units. For some results, the rounding procedure used in data reporting may result in apparent differences between the numbers reported in SI and conventional units. (For example, stack air tritium results reported as < 1.5 Bq/m3 are shown variously as < 39 and < 41 pCi/m3. Both of these results are rounded correctly to two significant digits.)

  20. Thermal mapping of mountain slopes on Mars by application of a Differential Apparent Thermal Inertia technique

    Science.gov (United States)

    Kubiak, Marta; Mège, Daniel; Gurgurewicz, Joanna; Ciazela, Jakub

    2015-04-01

    Thermal inertia (P) is an important property of geologic surfaces that essentially describes the resistance to temperature (T) change as heat is added. Most remote sensing data describe the surface only. P is a volume property that is sensitive to the composition of the subsurface, down to a depth reached by the diurnal heating wave. As direct measurement of P is not possible on Mars, thermal inertia models (Fergason et al., 2006) and deductive methods (the Apparent Thermal Inertia: ATI and Differential Apparent Thermal Inertia: DATI) are used to estimate it. ATI is computed as (1 - A) / (Tday - Tnight), where A is albedo. Due to the lack of the thermal daytime images with maximum land surface temperature (LST) and nighttime images with minimum LST in Valles Marineris region, the ATI method is difficult to apply. Instead, we have explored the DATI technique (Sabol et al., 2006). DATI is calculated based on shorter time (t) intervals with a high |ΔT/Δt| gradient (in the morning or in the afternoon) and is proportional to the day/night temperature difference (ATI), and hence P. Mars, which exhibits exceptionally high |ΔT/Δt| gradients due to the lack of vegetation and thin atmosphere, is especially suitable for the DATI approach. Here we present a new deductive method for high-resolution differential apparent thermal inertia (DATI) mapping for areas of highly contrasted relief (e.g., Valles Marineris). Contrary to the thermal inertia models, our method takes local relief characteristics (slopes and aspects) into account. This is crucial as topography highly influences A and ΔT measurements. In spite of the different approach, DATI values in the flat areas are in the same range as the values obtained by Fergason et al. (2006). They provide, however, more accurate information for geological interpretations of hilly or mountainous terrains. Sabol, D. E., Gillespie, A. R., McDonald, E., and Danilina, I., 2006. Differential Thermal Inertia of Geological Surfaces. In

  1. Ionic molal conductivities, activity coefficients, and dissociation constants of HAsO42− and H2AsO4− from 5 to 90°C and ionic strengths from 0.001 up to 3 mol kg−1 and applications in natural systems

    Science.gov (United States)

    Zhu, Xiangyu; Nordstrom, D. Kirk; McCleskey, R. Blaine; Wang, Rucheng

    2016-01-01

    Arsenic is known to be one of the most toxic inorganic elements, causing worldwide environmental contamination. However, many fundamental properties related to aqueous arsenic species are not well known which will inhibit our ability to understand the geochemical behavior of arsenic (e.g. speciation, transport, and solubility). Here, the electrical conductivity of Na2HAsO4 solutions has been measured over the concentration range of 0.001–1 mol kg−1 and the temperature range of 5–90°C. Ionic strength and temperature-dependent equations were derived for the molal conductivity of HAsO42−and H2AsO4− aqueous ions. Combined with speciation calculations and the approach used by McCleskey et al. (2012b), these equations can be used to calculate the electrical conductivities of arsenic-rich waters having a large range of effective ionic strengths (0.001–3 mol kg−1) and temperatures (5–90°C). Individual ion activity coefficients for HAsO42− and H2AsO4− in the form of the Hückel equation were also derived using the mean salt method and the mean activity coefficients of K2HAsO4 (0.001–1 mol kg−1) and KH2AsO4 (0.001–1.3 mol kg−1). A check on these activity coefficients was made by calculating mean activity coefficients for Na2HAsO4 and NaH2AsO4 solutions and comparing them to measured values. At the same time Na-arsenate complexes were evaluated. The NaH2AsO40 ion pair is negligible in NaH2AsO4 solutions up to 1.3 mol kg−1. The NaHAsO4− ion pair is important in NaHAsO4 solutions >0.1 mol kg−1 and the formation constant of 100.69 was confirmed. The enthalpy, entropy, free energy and heat capacity for the second and third arsenic acid dissociation reactions were calculated from pH measurements. These properties have been incorporated into a widely used geochemical calculation code WATEQ4F and applied to natural arsenic waters. For arsenic spiked water samples from Yellowstone National Park, the mean difference between the

  2. Apparent resistivity and spectral induced polarization in the submarine environment

    Directory of Open Access Journals (Sweden)

    HERCULES DE SOUZA

    2001-09-01

    Full Text Available Relatively few investigations have employed electrical methods in the submarine environment, which may be promising for mineral deposits or threatened by environmental problems. We have measured the electric field using both disk and bar electrodes in the sea water at three different levels: sea surface, seven meters deep, and sea bottom at a depth of ten meters, employing a 2 m spacing dipole-dipole array with 7 array spacings of investigation, and 13 values of frequencies at steps of (2N hertz, N = -2, -1, 0, 1, 2,.....10. The measurement allowed the analysis of the electric field as a function of frequency and spacing, and of the spectral induced polarization. Modelling and interpretation of the apparent resistivity yielded a good fit with previous drilling data. Analysis of the spectrum of the complex apparent resistivity and the comparison with equivalent circuits, provided information about the grain size, the mineral composition and the major induced polarization phenomenon occurring below the sea. Therefore the result of the present research show the feasibility of measuring the variation of seawater resistivity in situ, as well as the resistivity of sea bottom sediments.Relativamente poucas investigações têm empregado métodos elétricos no ambiente submarino, o qual pode ser promissor para depósitos minerais ou ameaçado por problemas ambientais. Nós medimos o campo elétrico usando eletrodos em forma de disco e de barra na água do mar, em três níveis distintos: superfície, sete metros de profundidade, e fundo do mar a dez metros de profundidade, empregando um dispositivo dipolo-dipolo com 2m de afastamento, 7 níveis de investigação e 13 valores de freqüência a intervalos de (2N hertz, N = -2, -1, 0, 1, 2, ... 10. A medida permitiu a análise do campo elétrico como uma função de freqüência e afastamento, e da polarização induzida espectral. A modelagem e a interpretação da resistividade aparente se ajustaram bem

  3. Apparent in vivo nutrient digestibility of maize silages in horses

    Directory of Open Access Journals (Sweden)

    Adriana PÍŠOVÁ

    2016-12-01

    Full Text Available The aim of the experiment was to analyzed coefficients of digestibility of the maize silage nutrients in horse feeding. Horses of Slovak warmblood breed engaged in the research were 2.5 ± 0.5 years old. Horses in boxes without bedding to avoid eating it and excrement contamination were stabled. Horses individually with ad libitum access to water were housed. The boxes with trough for corn silage were equiped. The corn silage contained 362.3 g of dry matter, 74.1 g of crude protein, 27.1 g of crude fat and 948.2 g of organic matter in kg of dry matter. The feed twice a day, in the morning and in the evening was given. The feed intake and leftovers were weighed every day. Excrements immediately after excreting to avoid urine contamination into plastic containers were collected and weighed. The content of nutrients in the feed intake and in the excrements were analysed. In analysed samples the gravimetric dry matter amount by drying at 103 ± 2 °C, crude protein content by Kjeldahl method, fat content by extraction method according to Soxhlett – Henkel, ash content by burning the sample at 530 ± 20 °C in muffle furnace and organic matter content by calculation were determined. Coefficients of apparent digestibility in percent from taken in and excreted nutrients were calculated. In maize silage for horse feeding an average coefficient of digestibility of dry matter 61.94%, of crude protein 56.03%, of crude fat 72.34% and of organic matter 65.19% was found.

  4. Estimating groundwater velocity using apparent resistivity tomography: A sandbox experiment

    Science.gov (United States)

    Chen, J. L.; Chen, C. H.; Kuo, C. L.; Fen, C. S.; Wu, C. C.

    2016-08-01

    The electrical resistivity tomography (ERT) technique can estimate groundwater velocity to within 5% of the pre-set groundwater velocity. The apparent conductivity obtained by the ERT technique is linearly related to the groundwater conductivity, as described by Archie's law. Gaussian-like profiles of the tracer concentration were demonstrated with the ERT technique, and the estimated dispersion coefficient was between 0.0015 and 0.0051 cm2/sec. In terms of monitoring changes in groundwater conductivity, the ERT technique has two major advantages over monitoring wells: (1) it measures a larger area and provides more representative results; and, (2) it does not withdraw groundwater samples, and therefore does not affect the groundwater flow. The objective of this research is to measure groundwater velocity with the ERT technique using only one well. The experiments in this research were divided into two parts. The first part evaluated the accuracy and repeatability of the ERT technique using a dipole-dipole array, and the second part estimated the groundwater velocity in a sandbox using the ERT technique. The length, width, and height of the sandbox, which was made of acrylic, were 1.5, 5, and 1.0 m, respectively. The ERT sandbox was sequentially filled with 5-cm layers of the silica sand to a total height of 70 cm. A total of 32 electrodes spaced every 5-cm were installed in the center of the sandbox. Three monitoring wells were installed along the line of the electrodes. Both no-flow and constant flow (NaCl solution with electrical conductivity and concentration of 5,000 μs/cm and 2.456 g/L, respectively) tracer experiments were conducted.

  5. Gene Tree Discordance Causes Apparent Substitution Rate Variation.

    Science.gov (United States)

    Mendes, Fábio K; Hahn, Matthew W

    2016-07-01

    Substitution rates are known to be variable among genes, chromosomes, species, and lineages due to multifarious biological processes. Here, we consider another source of substitution rate variation due to a technical bias associated with gene tree discordance. Discordance has been found to be rampant in genome-wide data sets, often due to incomplete lineage sorting (ILS). This apparent substitution rate variation is caused when substitutions that occur on discordant gene trees are analyzed in the context of a single, fixed species tree. Such substitutions have to be resolved by proposing multiple substitutions on the species tree, and we therefore refer to this phenomenon as Substitutions Produced by ILS (SPILS). We use simulations to demonstrate that SPILS has a larger effect with increasing levels of ILS, and on trees with larger numbers of taxa. Specific branches of the species trees are consistently, but erroneously, inferred to be longer or shorter, and we show that these branches can be predicted based on discordant tree topologies. Moreover, we observe that fixing a species tree topology when performing tests of positive selection increases the false positive rate, particularly for genes whose discordant topologies are most affected by SPILS. Finally, we use data from multiple Drosophila species to show that SPILS can be detected in nature. Although the effects of SPILS are modest per gene, it has the potential to affect substitution rate variation whenever high levels of ILS are present, particularly in rapid radiations. The problems outlined here have implications for character mapping of any type of trait, and for any biological process that causes discordance. We discuss possible solutions to these problems, and areas in which they are likely to have caused faulty inferences of convergence and accelerated evolution.

  6. Phase-contrast MRI and CFD modeling of apparent 3He gas flow in rat pulmonary airways

    Science.gov (United States)

    Minard, Kevin R.; Kuprat, Andrew P.; Kabilan, Senthil; Jacob, Richard E.; Einstein, Daniel R.; Carson, James P.; Corley, Richard A.

    2012-08-01

    Phase-contrast (PC) magnetic resonance imaging (MRI) with hyperpolarized 3He is potentially useful for developing and testing patient-specific models of pulmonary airflow. One challenge, however, is that PC-MRI provides apparent values of local 3He velocity that not only depend on actual airflow but also on gas diffusion. This not only blurs laminar flow patterns in narrow airways but also introduces anomalous airflow structure that reflects gas-wall interactions. Here, both effects are predicted in a live rat using computational fluid dynamics (CFD), and for the first time, simulated patterns of apparent 3He gas velocity are compared with in vivo PC-MRI. Results show (1) that correlations (R2) between measured and simulated airflow patterns increase from 0.23 to 0.79 simply by accounting for apparent 3He transport, and (2) that remaining differences are mainly due to uncertain airway segmentation and partial volume effects stemming from relatively coarse MRI resolution. Higher-fidelity testing of pulmonary airflow predictions should therefore be possible with future imaging improvements.

  7. Evaluation and comparison of diffusion MR methods for measuring apparent transcytolemmal water exchange rate constant

    Science.gov (United States)

    Tian, Xin; Li, Hua; Jiang, Xiaoyu; Xie, Jingping; Gore, John C.; Xu, Junzhong

    2017-02-01

    Two diffusion-based approaches, CG (constant gradient) and FEXI (filtered exchange imaging) methods, have been previously proposed for measuring transcytolemmal water exchange rate constant kin, but their accuracy and feasibility have not been comprehensively evaluated and compared. In this work, both computer simulations and cell experiments in vitro were performed to evaluate these two methods. Simulations were done with different cell diameters (5, 10, 20 μm), a broad range of kin values (0.02-30 s-1) and different SNR's, and simulated kin's were directly compared with the ground truth values. Human leukemia K562 cells were cultured and treated with saponin to selectively change cell transmembrane permeability. The agreement between measured kin's of both methods was also evaluated. The results suggest that, without noise, the CG method provides reasonably accurate estimation of kin especially when it is smaller than 10 s-1, which is in the typical physiological range of many biological tissues. However, although the FEXI method overestimates kin even with corrections for the effects of extracellular water fraction, it provides reasonable estimates with practical SNR's and more importantly, the fitted apparent exchange rate AXR showed approximately linear dependence on the ground truth kin. In conclusion, either CG or FEXI method provides a sensitive means to characterize the variations in transcytolemmal water exchange rate constant kin, although the accuracy and specificity is usually compromised. The non-imaging CG method provides more accurate estimation of kin, but limited to large volume-of-interest. Although the accuracy of FEXI is compromised with extracellular volume fraction, it is capable of spatially mapping kin in practice.

  8. Contribution of chlorophyll fluorescence to the apparent vegetation reflectance

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, P.K. Entcheva [Joint Center for Earth Systems Technology, UMBC, Baltimore, MD 21228 (United States); Biospheric Sciences Branch, Hydrospheric and Biospheric Sciences Laboratory, NASA/GSFC, Greenbelt, MD 20771 (United States)], E-mail: pcampbel@pop900.gsfc.nasa.gov; Middleton, E.M. [Biospheric Sciences Branch, Hydrospheric and Biospheric Sciences Laboratory, NASA/GSFC, Greenbelt, MD 20771 (United States); Corp, L.A. [Biospheric Sciences Branch, Hydrospheric and Biospheric Sciences Laboratory, NASA/GSFC, Greenbelt, MD 20771 (United States); Agricultural Research Service, USDA, Beltsville, MD 20705 (United States); Kim, M.S. [Agricultural Research Service, USDA, Beltsville, MD 20705 (United States)

    2008-10-15

    Current strategies for monitoring the physiologic status of terrestrial vegetation rely on remote sensing reflectance data, which provide estimates of vigor based primarily on chlorophyll content. Chlorophyll fluorescence (ChlF) measurements offer a non-destructive alternative and a more direct approach for diagnosis of vegetation stress before a significant reduction in chlorophyll content has occurred. Thus, technology based on ChlF may allow more accurate carbon sequestration estimates and earlier stress detection than is possible when using reflectance data alone. However, the observed apparent vegetation reflectance (Ra) in reality includes contributions from both the reflected and fluoresced radiation. The aim of this study is to determine the relative contributions of reflectance and ChlF fractions to Ra in the red to near-infrared region (650-800 nm) of the spectrum. The practical objectives of the study are to: 1) evaluate the relationship between ChlF and reflectance at the foliar level for corn, soybean and maple; and 2) for corn, determine if the relationship established for healthy vegetation changes under nitrogen (N) deficiency. To obtain generally applicable results, experimental measurements were conducted on unrelated crop and tree species (corn, soybean and maple) under controlled conditions and a gradient of inorganic N fertilization levels. Optical reflectance spectra and actively induced ChlF emissions were collected on the same foliar samples, in conjunction with measurements of photosynthetic function, pigment levels, and carbon (C) and N content. The spectral trends were examined for similarities. On average, 10-20% of Ra at 685 nm was actually due to ChlF. The spectral trends in steady state and maximum fluorescence varied significantly, with steady state fluorescence (especially red, 685 nm) showing higher ability for species and treatment separation. The relative contribution of ChlF to Ra varied significantly among species, with maple

  9. Apparent interfacial shear strength of short-flax-fiber/starch acetate composites

    DEFF Research Database (Denmark)

    Andersons, J.; Modniks, J.; Joffe, R.

    2016-01-01

    The paper deals with an indirect industry-friendly method for identification of the interfacial shear strength (IFSS) in a fully bio-based composite. The IFSS of flax fiber/starch acetate is evaluated by a modified Bowyer and Bader method based on an analysis of the stress-strain curve of a short......-fiber-reinforced composite in tension. A shear lag model is developed for the tensile stress-strain response of short-fiber-reinforced composites allowing for an elastic-perfectly plastic stress transfer. Composites with different fiber volume fractions and a variable content of plasticizer have been analyzed. The apparent...... IFSS of flax/starch acetate is within the range of 5.5-20.5 MPa, depending on composition of the material. The IFSS is found to be greater for composites with a higher fiber loading and to decrease with increasing content of plasticizer. The IFSS is equal or greater than the yield strength of the neat...

  10. Age- and direction-related adaptations of lumbar vertebral trabecular bone with respect to apparent stiffness and tissue level stress distribution

    Science.gov (United States)

    Gong, He; Fan, Yubo; Zhang, Ming; Qin, Ling

    2009-02-01

    The objective of this study was to study the age-related adaptation of lumbar vertebral trabecular bone at the apparent level, as well as the tissue level in three orthogonal directions. Ninety trabecular specimens were obtained from six normal L4 vertebral bodies of six male cadavers in two age groups, three aged 62 years and three aged 69 years, and were scanned using a high-resolution micro-computed tomography (micro-CT) system, then converted to micro-finite element models to do micro-finite element analyses. The relationship between apparent stiffness and bone volume fraction, and the tissue level von Mises stress distribution for each trabecular specimen when compressed separately in the longitudinal direction, medial-lateral and anterior-posterior directions (transverse directions) were derived and compared between two age groups. The results showed that at the apparent level, trabecular bones from 69-year group had stiffer bone structure relative to their volume fractions in all three directions, and in both age groups, changes in bone volume fraction could explain more variations in apparent stiffness in the longitudinal direction than the transverse directions; at the tissue level, aging had little effect on the tissue von Mises stress distributions for the compressions in all the three directions. The novelty of the present study was that it provided quantitative assessments on the age and direction-related adaptation of Chinese male lumbar vertebral trabecular bone from two different levels: stiffness at the apparent level and stress distribution at the tissue level. It may help to understand the failure mechanisms and fracture risks of vertebral body associated with aging and direction for the prevention of fracture risks in elder individuals.

  11. Renormalized Volume

    CERN Document Server

    Gover, A Rod

    2016-01-01

    For any conformally compact manifold with hypersurface boundary we define a canonical renormalized volume functional and compute an explicit, holographic formula for the corresponding anomaly. For the special case of asymptotically Einstein manifolds, our method recovers the known results. The anomaly does not depend on any particular choice of regulator, but the coefficients of divergences do. We give explicit formulae for these divergences valid for any choice of regulating hypersurface; these should be relevant to recent studies of quantum corrections to entanglement entropies. The anomaly is expressed as a conformally invariant integral of a local Q-curvature that generalizes the Branson Q-curvature by including data of the embedding. In each dimension this canonically defines a higher dimensional generalization of the Willmore energy/rigid string action. We show that the variation of these energy functionals is exactly the obstruction to solving a singular Yamabe type problem with boundary data along the...

  12. [Grain Size Distribution Characteristics of Suspended Particulate Matter as Influenced by the Apparent Pollution in the Eutrophic Urban Landscape Water Body].

    Science.gov (United States)

    Gong, Dan-yan; Pan, Yang; Huang, Yong; Bao, Wei; Li, Qian-qian

    2016-03-15

    Grain size distribution characteristics of suspended particulate matter (SPM) reflects the apparent polluted condition of the urban landscape water. In order to explore the internal relationship between the eutrophication of urban landscape water's apparent pollution and grain size distribution of SPM, and its influencing factors, this paper selected five representative sampling sites in Feng Jin River which is a typical eutrophication river in Suzhou City, measured the grain size distribution of SPM, sensation pollution index (SPI) and water quality index, and analyzed their correlation. The results showed that: The rich nutrient water possessed a similar characteristics in grain size distribution. The grain size distribution of SPM in water was multimodal, and the the peak position was roughly the same; the grain size distribution of SPM was composed by multiple components. It could be roughly divided into six parts with the particle size range of every group being 516 µm. The component III was superior (with an average volume fraction of 38.3%-43.2%), and its volume fraction had a significant positive relation with the SPI value and the Chl-a content. The increase of component III volume fraction was the reflection of particle size's result of increasing SPI value. The increase of component III volume fraction was mainly derived from the increasing algal content. The volume fraction of group IV + group VI + group V was significantly higher under the condition of exogenous enter. When there was no exogenous component, the volume fraction of group IV + group VI + group V had a significant negative correlation with SPI value; when there were exogenous components, the volume fraction of group IV + group VI + group V had a weak positive correlation with SPI value, but the correlation did not reach a significant level. Environmental factors (Fv/Fm and DO) and exogenous factors had an influence by functioning on the algal content which signified the polluted material

  13. On the volume inside old black holes

    CERN Document Server

    Christodoulou, Marios

    2016-01-01

    Black holes that have nearly evaporated are often thought of as small objects, due to their tiny exterior area. However, the horizon bounds large spacelike hypersurfaces. A compelling geometric perspective on the evolution of the interior geometry was recently shown to be provided by a generally covariant definition of the volume inside a black hole using maximal surfaces. In this article, we expand on previous results and show that finding the maximal surfaces in an arbitrary spherically symmetric spacetime is equivalent to a 1+1 geodesic problem. We then study the effect of Hawking radiation on the volume by computing the volume of maximal surfaces inside the apparent horizon of an evaporating black hole as a function of time at infinity: while the area is shrinking, the volume of these surfaces grows monotonically with advanced time, up to when the horizon has reached Planckian dimensions. The physical relevance of these results for the information paradox and the remnant scenarios are discussed.

  14. Stochastic multi-scale prediction on the apparent elastic moduli of trabecular bone considering uncertainties of biological apatite (BAp) crystallite orientation and image-based modelling.

    Science.gov (United States)

    Basaruddin, Khairul Salleh; Takano, Naoki; Nakano, Takayoshi

    2015-01-01

    An assessment of the mechanical properties of trabecular bone is important in determining the fracture risk of human bones. Many uncertainty factors contribute to the dispersion of the estimated mechanical properties of trabecular bone. This study was undertaken in order to propose a computational scheme that will be able to predict the effective apparent elastic moduli of trabecular bone considering the uncertainties that are primarily caused by image-based modelling and trabecular stiffness orientation. The effect of image-based modelling which focused on the connectivity was also investigated. A stochastic multi-scale method using a first-order perturbation-based and asymptotic homogenisation theory was applied to formulate the stochastically apparent elastic properties of trabecular bone. The effective apparent elastic modulus was predicted with the introduction of a coefficient factor to represent the variation of bone characteristics due to inter-individual differences. The mean value of the predicted effective apparent Young's modulus in principal axis was found at approximately 460 MPa for respective 15.24% of bone volume fraction, and this is in good agreement with other experimental results. The proposed method may provide a reference for the reliable evaluation of the prediction of the apparent elastic properties of trabecular bone.

  15. Repetitive transcranial magnetic stimulation of human MT+ reduces apparent motion perception.

    Science.gov (United States)

    Matsuyoshi, Daisuke; Hirose, Nobuyuki; Mima, Tatsuya; Fukuyama, Hidenao; Osaka, Naoyuki

    2007-12-18

    We investigated the effects of repetitive transcranial magnetic stimulation (rTMS) over the human cerebral cortex on apparent motion perception. Previous studies have shown that human extrastriate visual area MT+ (V5) processes not only real but also apparent motion. However, the functional relevance of MT+ on long-range apparent motion perception remains unclear. Here, we show direct evidence for the involvement of MT+ in apparent motion perception using rTMS, which is known to temporarily inhibit a localized region in the cerebral cortex. The results showed that apparent motion perception decreased after applying rTMS over MT+, but not after applying rTMS over the control region (inferior temporal gyrus). The decrease in performance caused by applying rTMS to MT+ suggests that MT+ is a causally responsible region for apparent motion perception, and thus, further supports the idea that MT+ plays a major role in the perception of motion.

  16. Electric potential and apparent resistivity in rocks containing non-uniformly distributed cracks

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In this paper, the formula of electric field distribution and ground apparent resistivity of high resistance rock medi-um containing low resistance crack are deduced and simulated. The result shows that interstitial parameters, such as buried depth, scale, strike, and real resistivity, etc, have influence on observation and computing result of apparent resistivity. This study provided a useful foundation for earthquake prediction using apparent resistivity method.

  17. Apparent size contrasts of retinal images and size constancy as determinants of the moon illusion.

    Science.gov (United States)

    Smith, O W; Smith, P C; Geist, C C; Zimmermann, R R

    1978-06-01

    Kaufman and Rock (1962) and Rock and Kaufman (1962) concluded that the moon illusion is a function of and attributable to apparent distance. They also reported a large framing effect as an exception. Analysis of the effect suggests two components which can account for the illusion independently of apparent distance. These are apparent size contrasts of visual images of discriminable features or objects of the earth with the moon's image and size constancy of the features or objects plus the interactions of the two. Apparent distances to horizons are always a consequence of the necessary conditions for the illusion. They are related to the illusion but are not a determinant of it.

  18. Criteria for cure in acromegaly: report of a case apparently cured in which persisting tumor was found at autopsy.

    Science.gov (United States)

    Wrightson, P; Holdaway, I M; Synek, B J

    1984-06-01

    A 49-year-old man with acromegaly underwent the apparently complete removal of a pituitary microadenoma by the transsphenoidal route. There was complete remission of the biochemical abnormalities for 2 1/2 years, with basal plasma growth hormone (GH) levels of less than 1 ng/ml and normal somatomedin levels. The patient then died after the rupture of a cerebral aneurysm. Serial sections of the pituitary fossa showed persistent tumor with a volume of about 6% of the remaining normal gland. It is concluded that current endocrine tests are limited in their ability to detect residual GH-secreting tumor. Their sensitivity is likely to depend on the mass of tumor and on the GH secretion rate. Predictions of long term cure based on these tests are only tentative.

  19. Apparent Rate Constant for Diffusion-Controlled Three molecular (catalytic) reaction

    OpenAIRE

    Burlatsky, S. F.; Moreau, M

    1996-01-01

    We present simple explicit estimates for the apparent reaction rate constant for three molecular reactions, which are important in catalysis. For small concentrations and $d> 1$, the apparent reaction rate constant depends only on the diffusion coefficients and sizes of the particles. For small concentrations and $d\\le 1$, it is also time -- dependent. For large concentrations, it gains the dependence on concentrations.

  20. Financial Barriers for Students with Non-Apparent Disabilities within Canadian Postsecondary Education

    Science.gov (United States)

    Chambers, Tony; Bolton, Melissa; Sukhai, Mahadeo A.

    2013-01-01

    This study examined the education-related debt, sources of debt, and the process of acquiring accommodations for students with non-apparent (such as learning disabilities and mental health disabilities) and apparent disabilities in Canadian postsecondary education. A third group emerged during analyses, students with medical disabilities, which…

  1. Taking a Hands-On Approach: Apparent Grasping Ability Scales the Perception of Object Size

    Science.gov (United States)

    Linkenauger, Sally A.; Witt, Jessica K.; Proffitt, Dennis R.

    2011-01-01

    We examined whether the apparent size of an object is scaled to the morphology of the relevant body part with which one intends to act on it. To be specific, we tested if the visually perceived size of graspable objects is scaled to the extent of apparent grasping ability for the individual. Previous research has shown that right-handed…

  2. Thermodynamical properties of interacting holographic dark energy model with apparent horizon

    CERN Document Server

    Liu, Bin; Deng, Jian-Bo

    2011-01-01

    We have investigated the thermodynamical properties of the universe with dark energy. It is demonstrated that in a universe with spacial curvature the natural choice for IR cutoff could be the apparent horizon radius. We shown that any interaction of pressureless dark matter with holographic dark energy, whose infrared cutoff is set by the apparent horizon radius, implying a constant effective equation of state of dark component in a universe. In addition we found that for the static observer in space, the comoving distance has a faster expansion than the apparent horizon radius with any spatial curvature. We also verify that in some conditions the modified first law of thermodynamics could return to the classic form at apparent horizon for a universe filled with dark energy and dark matter. Besides, the generalized second law of thermodynamics is discussed in a region enclosed by the apparent horizon.

  3. Study of solute-solvent interaction of chlorosubstituted pyrazoles with Cu (II) and Tb (III) and dioxane-water at various temperatures

    Science.gov (United States)

    Ramteke, Avinash A.; Chavan, Sugam P.

    2016-05-01

    The solute-solvent interactions of complexes of chloro substituted pyrazole with Cu (II) and Tb (III) metal ions as a function of temperature has been studied by measuring density and ultrasonic velocity at different temperatures. The values of density and ultrasonic velocity have been used to determine the adiabatic compressibility βs, apparent molal volume ϕv, apparent adiabatic compressibility ϕk, intermolecular free length Lf, relative association RA and acoustic impendence Z. The obtained results from the acoustic parameters show the significant interaction between the complex and solvent.

  4. Isometric stress in cardiovascular magnetic resonance - a simple and easily replicable method of assessing cardiovascular differences not apparent at rest

    Energy Technology Data Exchange (ETDEWEB)

    Mortensen, Kristian H.; Jones, Alexander; Steeden, Jennifer A.; Taylor, Andrew M.; Muthurangu, Vivek [UCL Centre for Cardiovascular MR, UCL Institute of Cardiovascular Science, Level 6 Old Nurses Home, Cardiorespiratory Unit, Great Ormond Street Hospital for Children, London (United Kingdom)

    2016-04-15

    Isometric exercise may unmask cardiovascular disease not evident at rest, and cardiovascular magnetic resonance (CMR) imaging is proven for comprehensive resting assessment. This study devised a simple isometric exercise CMR methodology and assessed the hemodynamic response evoked by isometric exercise. A biceps isometric exercise technique was devised for CMR, and 75 healthy volunteers were assessed at rest, after 3-minute biceps exercise, and 5-minute of recovery using: (1) blood pressure (BP) and (2) CMR measured aortic flow and left ventricular function. Total peripheral resistance (SVR) and arterial compliance (TAC), cardiac output (CO), left ventricular volumes and function (ejection fraction, stroke volume, power output), blood pressure (BP), heart rate (HR), and rate pressure product were assessed at all time points. Image quality was preserved during stress. During exercise there were increases in CO (+14.9 %), HR (+17.0 %), SVR (+9.8 %), systolic BP (+22.4 %), diastolic BP (+25.4 %) and mean BP (+23.2 %). In addition, there were decreases in TAC (-22.0 %) and left ventricular ejection fraction (-6.3 %). Age and body mass index modified the evoked response, even when resting measures were similar. Isometric exercise technique evokes a significant cardiovascular response in CMR, unmasking physiological differences that are not apparent at rest. (orig.)

  5. Volume of the effect compartment in simulations of neuromuscular block

    NARCIS (Netherlands)

    Nigrovic, Vladimir; Proost, Johannes H.; Amann, Anton; Bhatt, Shashi B.

    2005-01-01

    Background: The study examines the role of the volume of the effect compartment in simulations of neuromuscular block (NMB) produced by nondepolarizing muscle relaxants. Methods: The molar amount of the postsynaptic receptors at the motor end plates in muscle was assumed constant; the apparent recep

  6. On temporal and spatial distribution of seismic apparent stresses in Yunnan area

    Institute of Scientific and Technical Information of China (English)

    QIN Jia-zheng; QIAN Xiao-dong

    2006-01-01

    motion is applied to a detailed study on the temporal and spatial distribution of the seismic apparent stresses (σa)for the moderate and small earthquakes and two aftershock sequences in Yunnan area. The results show that there exists an obvious non-homogeneity for the seismic apparent stresses in the spatial distribution. The concentrated regions of the high apparent stresses are related to the active places of the moderate and small earthquakes. Before the Dayao M=6.2 earthquake, there was a period in which the apparent stresses were high and the value was 5times of the average value, 0.25 MPa. The relatively high values of apparent stresses distribute around the epicentral area of the major shock and nearby. It indicates that the variation characteristics of the apparent stresses can be taken as a new kind of criterion for the earthquake-risk forecast. Usually the ratio of the apparent stresses of the aftershock sequence σaA to the ones σaM of main shock is less than 1.0.

  7. Primary visual cortex activity along the apparent-motion trace reflects illusory perception.

    Directory of Open Access Journals (Sweden)

    Lars Muckli

    2005-08-01

    Full Text Available The illusion of apparent motion can be induced when visual stimuli are successively presented at different locations. It has been shown in previous studies that motion-sensitive regions in extrastriate cortex are relevant for the processing of apparent motion, but it is unclear whether primary visual cortex (V1 is also involved in the representation of the illusory motion path. We investigated, in human subjects, apparent-motion-related activity in patches of V1 representing locations along the path of illusory stimulus motion using functional magnetic resonance imaging. Here we show that apparent motion caused a blood-oxygenation-level-dependent response along the V1 representations of the apparent-motion path, including regions that were not directly activated by the apparent-motion-inducing stimuli. This response was unaltered when participants had to perform an attention-demanding task that diverted their attention away from the stimulus. With a bistable motion quartet, we confirmed that the activity was related to the conscious perception of movement. Our data suggest that V1 is part of the network that represents the illusory path of apparent motion. The activation in V1 can be explained either by lateral interactions within V1 or by feedback mechanisms from higher visual areas, especially the motion-sensitive human MT/V5 complex.

  8. All-time Apparent Vertical Conductance Interpretation for CLTEM and Its Application

    Institute of Scientific and Technical Information of China (English)

    YanLiangjun; HuWenbao; Xushizhe; LuYi

    2003-01-01

    This paper is based on the transient electromagnetic theory of a thin sheet. The induced EMF formula (as a function of vertical conductance and depth in the central loop transient electromagnetic method) was derived by using the reciprocation law and the formula from the electrical component of EMF induced by a magnetic dipole source over a thin sheet. At the same time, the inversion algorithm of all-time apparent vertical conductance and apparent depth was derived by using the induced EMF and its first derivative. In the transition area there is no distortion for the calculated apparent vertical conductance curve. The location where the curves slope was changing corresponds to an electric interface of the layer. This is because the curve of the slope is directly proportional to the conductivity. Comparing the shapes of the neighboring curves in the same section line, the interfaces of the same layer can be continuously traced, resulting in a high quality CLTEM get-electric section. Theoretical testing with two models shows that the curves of all-time apparent vertical conductance represents the electric property of each layer and its variation. Finally, the authors show application examples of apparent vertical conductance interpretation. The mapped apparent vertical conductance section has fine electric division from the inversion algorithm and is in good co-herence with the inverted resistivity section. This demonstrates that the interpretation method of all-time apparent vertical conductance is feasible and effective

  9. Identification of Stress Change Within a Rock Mass Through Apparent Stress of Local Seismic Events

    Science.gov (United States)

    Brown, Laura; Hudyma, Martin

    2017-01-01

    Mine blasting produces excavation geometry changes which induce stress change that can be observed in the seismic source parameter apparent stress calculated for local seismic events. Using high apparent stress as a proxy for increasing stress within a rock mass, areas experiencing increases in the local stress conditions can be determined. This paper presents the use of apparent stress of seismic events to identify areas within a rock mass experiencing local stress change. Examples from a deep Canadian mine, operating in excess of 2900 m below surface, are provided.

  10. Tritium/Helium-3 Apparent Ages of Shallow Ground Water, Portland Basin, Oregon, 1997-98

    Science.gov (United States)

    Hinkle, Stephen R.

    2009-01-01

    Water samples for tritium/helium-3 age dating were collected from 12 shallow monitoring wells in the Portland basin, Oregon, in 1997, and again in 1998. Robust tritium/helium-3 apparent (piston-flow) ages were obtained for water samples from 10 of the 12 wells; apparent ages ranged from 1.1 to 21.2 years. Method precision was demonstrated by close agreement between data collected in 1997 and 1998. Tritium/helium-3 apparent ages generally increase with increasing depth below the water table, and agree well with age/depth relations based on assumptions of effects of recharge rate on vertical ground-water movement.

  11. Response of Swimming Paramecia to in situ changes in their apparent weight

    Science.gov (United States)

    Jung, Ilyong; Mickalide, Harry; Valles, James M., Jr.

    2012-02-01

    There is a class of marine micro-organisms that are small enough that low Reynold's number hydrodynamics dictates their swimming mechanics and large enough that the force of gravity exerts a noticeable influence on their motion. Experiments on populations of paramecia suggest that they exert a greater propulsion when swimming against gravity. This negative gravi-kinesis is surprising because it suggests that they sense their tiny apparent weight of about 80 pN. To understand this response in more detail, we are investigating how individual paramecia caudatum change their swimming speed and helical trajectories in response to changes in their apparent weight. We vary the apparent weight with the technique of Magnetic Force Buoyancy Variation employing a high field resistive magnet at the National High Magnetic Field Laboratory. We will present analysis of the swimming for apparent weight changes as large as a factor of 8.

  12. Apparent Activation Energy of Concrete in Early Age Determined by Adiabatic Test

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The apparent activation energy of concrete in early age was determined by adiabatic temperature rise test with different initial temperatures. The influence of mineral admixtures such as fly ash, slag and silica fume on the apparent activation energy of concrete was investigated. The equivalent age that expresses the maturity of concrete was calculated to evaluate the cracking risk of concrete in structures. The results reveal that a substitution of 20% fly ash for Portland cement obviously decreases the apparent activation energy of concrete, however, a substitution of 10% silica fume for Portland cement increases the apparent activation. Finite element method analysis of a simulating concrete wall shows that the concrete containing 20% fly ash has the lowest cracking risk.

  13. NUMERICAL STUDY OF THE RELATIONSHIP BETWEEN APPARENT SLIP LENGTH AND CONTACT ANGLE BY LATTICE BOLTZMANN METHOD

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ren-liang; DI Qin-feng; WANG Xin-liang; DING Wei-peng; GONG Wei

    2012-01-01

    The apparent slip between solid wall and liquid is studied by using the Lattice Boltzmann Method (LBM) and the Shan-Chen multiphase model in this paper.With a no-slip bounce-back scheme applied to the interface,flow regimes under different wall wettabilities are investigated.Because of the wall wettability,liquid apparent slip is observed.Slip lengths for different wall wettabilities are found to collapse nearly onto a single curve as a function of the static contact angle,and thereby a relationship between apparent slip length and contact angle is suggested.Our results also show that the wall wettability leads to the formation of a low-density layer between solid wall and liquid,which produced apparent slip in the micro-scale.

  14. First law of thermodynamics for dynamical apparent horizons and the entropy of Friedmann universes

    CERN Document Server

    Viaggiu, Stefano

    2015-01-01

    Recently, we have generalized the Bekenstein-Hawking entropy formula for black holes embedded in expanding Friedmann universes. In this letter, we begin the study of this new formula to obtain the first law of thermodynamics for dynamical apparent horizons. In this regard we obtain a generalized expression for the internal energy $U$ together with a distinction between the dynamical temperature $T_D$ of apparent horizons and the related one due to thermodynamics formulas. Remarkable, when the expression for $U$ is applied to the apparent horizon of the universe, we found that this internal energy is a constant of motion. Our calculations thus show that the total energy of our spatially flat universe including the gravitational contribution, when calculated at the apparent horizon, is an universal constant that can be set to zero from simple dimensional considerations. This strongly support the holographic principle.

  15. Time operator for the quantum harmonic oscillator resolution of an apparent paradox

    CERN Document Server

    Granik, A; Granik, Alex

    2000-01-01

    An apparent paradox is resolved that concerns the existence of time operators which have been derived for the quantum harmonic oscillator. There is an apparent paradox because, although a time operator is canonically conjugate to the Hamiltonian, it has been asserted that no operator exists that is canonically conjugate to the Hamiltonian. In order to resolve the apparent paradox, we work in a representation where the phase operator is diagonal. The boundary condition on wave functions is such that they be periodic in the phase variable, which is related to the (continuous) eigenvalue of the time operator. Matrix elements of the commutator of the time operator with the Hamiltonian involve the phase variable itself in addition to periodic functions of the phase variable. The Hamiltonian is not hermitian when operating in space that includes the phase variable itself. The apparent paradox is resolved when this non-hermeticity is taken into account correctly in the evaluation of matrix elements of the commutatio...

  16. Model of apparent crystal growth rate and kinetics of seeded precipitation from sodium aluminate solution

    Institute of Scientific and Technical Information of China (English)

    LI Xiao-bin; LIU Zhi-jian; XU Xiao-hui; ZHOU Qiu-sheng; PENG Zhi-hong; LIU Gui-hua

    2005-01-01

    Based on the population balance equation in a batch crystallizer characteristic of seeded precipitation, a model to calculate the rate of apparent crystal growth of aluminum hydroxide from the size distribution was deve-loped. The simulation results indicate that the rate of apparent crystal growth during seeded precipitation exhibits a manifest dependence on the crystal size. In general, there is an obvious increase in the apparent crystal growth rate with the augment in crystal size. The apparent activation energy increases with the increase of characteristic crystal size, which indicates that the growth of small crystals is controlled by surface chemical reaction; it is gradually controlled by both the surface reaction and diffusion with the augment in crystal size.

  17. Estimating true instead of apparent survival using spatial Cormack-Jolly-Seber models

    Science.gov (United States)

    Schaub, Michael; Royle, J. Andrew

    2014-01-01

    Survival is often estimated from capture–recapture data using Cormack–Jolly–Seber (CJS) models, where mortality and emigration cannot be distinguished, and the estimated apparent survival probability is the product of the probabilities of true survival and of study area fidelity. Consequently, apparent survival is lower than true survival unless study area fidelity equals one. Underestimation of true survival from capture–recapture data is a main limitation of the method.

  18. Apparent contact angle and contact angle hysteresis on liquid infused surfaces

    OpenAIRE

    Semprebon, Ciro; McHale, Glen; Kusumaatmaja, Halim

    2017-01-01

    We theoretically investigate the apparent contact angle and contact angle hysteresis of a droplet placed on a liquid infused surface. We show that the apparent contact angle is not uniquely defined by material parameters, but also has a strong dependence on the relative size between the droplet and its surrounding wetting ridge formed by the infusing liquid. We derive a closed form expression for the contact angle in the limit of vanishing wetting ridge, and compute the correction for small b...

  19. What should be the apparent viscosity target of a coal-water slurry fuel for combustion?

    Energy Technology Data Exchange (ETDEWEB)

    Pisupati, S.V.; Morrison, J.L.; Scaroni, A.W. [Pennsylvania State Univ., University Park, PA (United States)

    1997-12-31

    The rheological properties of a coal water slurry fuel (CWSF) affect its handling, atomization, and combustion behavior. The flow behavior and apparent viscosity are two rheological properties that are often specified by the end user. A pseudoplastic (shear thinning) flow behavior is preferred since there is a decrease in the apparent viscosity as the fuel is pumped to, and then atomized into the boiler. Specifying an apparent viscosity target for the CWSF is more problematic since there are often competing forces to maximize the solids loading of the fuel while minimizing the apparent viscosity. The apparent viscosity is a function of the particle size distribution of the coal, the solids loading of the CWSF, the physical and chemical properties of the coal, and the additive package used to prepare the CWSF. Targeting an apparent viscosity is necessary during the formulation and production of a CWSF. The trade off between maximizing the solids loading in order to increase the BTU content and maintaining an acceptable apparent viscosity to ensure good atomization behavior is not well established. In order to better define this trade-off, an investigation was carried out to examine the interrelationship between solids loading, apparent viscosity, atomization behavior, and the combustion performance of a CWSF. The CWSF was prepared in a continuous ball mill and isolated in a storage tank. Small batches of CWSF were taken from the storage tank and then diluted to determine how the changes in the CWSF`s rheology and solids loading affected it`s atomization and combustion behavior.

  20. Anomalous Increase of Apparent Mass in a Silo due to Percolation

    Institute of Scientific and Technical Information of China (English)

    Ram Chand; Abdul Qadir; SHI Qing-Fan; ZHENG Ning; SUN Gang

    2011-01-01

    The apparent mass at the bottom of a granular pile confined in a vertical tube decreases for denser granular packing. We report that the denser granular packing comprising two different diameters of granules augments the apparent mass instead. This anomalous behavior occurs when small granules are stacked on the large ones. In the case of anomalous increase, a percolation effect is found and correlated with the augment of apparent mass at the bottom of the granular column. Finally, the results are qualitatively explained by using the Janssen model.%@@ The apparent mass at the bottom of a granular pile confined in a vertical tube decreases for denser granular packing.We report that the denser granular packing comprising two different diameters of granules augments the apparent mass instead.This anomalous behavior occurs when small granules are stacked on the large ones.In the case of anomalous increase,a percolation effect is found and correlated with the augment of apparent mass at the bottom of the granular column.Finally,the results are qualitatively explained by using the Janssen model.

  1. Ovarian volume throughout life

    DEFF Research Database (Denmark)

    Kelsey, Thomas W; Dodwell, Sarah K; Wilkinson, A Graham

    2013-01-01

    cancer. To date there is no normative model of ovarian volume throughout life. By searching the published literature for ovarian volume in healthy females, and using our own data from multiple sources (combined n=59,994) we have generated and robustly validated the first model of ovarian volume from...... to about 2.8 mL (95% CI 2.7-2.9 mL) at the menopause and smaller volumes thereafter. Our model allows us to generate normal values and ranges for ovarian volume throughout life. This is the first validated normative model of ovarian volume from conception to old age; it will be of use in the diagnosis...

  2. Mean nuclear volume

    DEFF Research Database (Denmark)

    Mogensen, O.; Sørensen, Flemming Brandt; Bichel, P.

    1999-01-01

    We evaluated the following nine parameters with respect to their prognostic value in females with endometrial cancer: four stereologic parameters [mean nuclear volume (MNV), nuclear volume fraction, nuclear index and mitotic index], the immunohistochemical expression of cancer antigen (CA125...

  3. The apparent contact angle of water droplet on the micro-structured hydrophobic surface

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The apparent contact angle of Cassie-Baxter state water droplets can be calculated by the existing theoretical formula, but due to the defects of the micro-structured hydrophobic surface and some inevitable tiny disturbances in the experiment, Cassie-Baxter state water droplets will appear partly in Wenzel state, that is, the mixed state water droplets. In this paper, apparent contact angles of Cassie-Baxter state and mixed state water droplets on micro-structured hydrophobic surfaces are compared. The research shows that if the projected area fraction of water-solid F in the Cassie-Baxter formula is replaced by the local projected area fraction of water-solid F′, the apparent contact angles of water droplets in both Cassie-Baxter state and the mixed state can be calculated. Further experimental results indicate that the contact state of water droplets nearby the outermost three-phase contact line plays a more important role in determining the apparent contact angle. This conclusion is significant to the understanding of the apparent contact angle and wetting property.

  4. Apparent plasticity in functional traits determining competitive ability and spatial distribution: a case from desert.

    Science.gov (United States)

    Xie, Jiang-Bo; Xu, Gui-Qing; Jenerette, G Darrel; Bai, Yong-fei; Wang, Zhong-Yuan; Li, Yan

    2015-07-20

    Species competitive abilities and their distributions are closely related to functional traits such as biomass allocation patterns. When we consider how nutrient supply affects competitive abilities, quantifying the apparent and true plasticity in functional traits is important because the allometric relationships among traits are universal in plants. We propose to integrate the notion of allometry and the classical reaction norm into a composite theoretical framework that quantifies the apparent and true plasticity. Combining the framework with a meta-analysis, a series of field surveys and a competition experiment, we aimed to determine the causes of the dune/interdune distribution patterns of two Haloxylon species in the Gurbantonggut Desert. We found that (1) the biomass allocation patterns of both Haloxylon species in responses to environmental conditions were apparent rather than true plasticity and (2) the allometric allocation patterns affected the plants' competition for soil nutrient supply. A key implication of our results is that the apparent plasticity in functional traits of plants determines their response to environmental change. Without identifying the apparent and true plasticity, we would substantially overestimate the magnitude, duration and even the direction of plant responses in functional traits to climate change.

  5. Relationships between brain water content and diffusion tensor imaging parameters (apparent diffusion coefficient and fractional anisotropy) in multiple sclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Sijens, Paul E.; Irwan, Roy; Potze, Jan Hendrik; Oudkerk, Matthijs [University Medical Center Groningen and University of Groningen, Department of Radiology, Groningen (Netherlands); Mostert, Jop P.; Keyser, Jacques de [University Medical Center Groningen and University of Groningen, Department of Neurology, Groningen (Netherlands)

    2006-04-15

    Fifteen multiple sclerosis patients were examined by diffusion tensor imaging (DTI) to determine fractional anisotropy (FA) and apparent diffusion coefficient (ADC) in a superventricular volume of interest of 8 x 8 x 2 cm{sup 3} containing gray matter (GM) and white matter (WM) tissue. Point resolved spectroscopy 2D-chemical shift imaging of the same volume was performed without water suppression. The water contents and DTI parameters in 64 voxels of 2 cm{sup 3} were compared. The water content was increased in patients compared with controls (GM: 244{+-}21 vs. 194{+-}10 a.u.; WM: 245{+-}32 vs. 190{+-}11 a.u.), FA decreased (GM: 0.226{+-}0.038 vs. 0.270{+-}0.020; WM: 0.337{+-}0.044 vs. 0.402{+-}0.011) and ADC increased [GM: 1134{+-}203 vs. 899{+-}28 (x 10{sup -6} mm{sup 2}/s); WM: 901{+-}138 vs. 751{+-}17 (x 10{sup -6} mm{sup 2}/s)]. Correlations of water content with FA and ADC in WM were strong (r=-0.68, P<0.02; r=0.75; P<0.01, respectively); those in GM were weaker (r=-0.50, P<0.05; r=0.45, P<0.1, respectively). Likewise, FA and ADC were more strongly correlated in WM (r=-0.88; P<0.00001) than in GM (r=-0.69, P<0.01). The demonstrated relationship between DTI parameters and water content in multiple sclerosis patients suggests a potential for therapy monitoring in normal-appearing brain tissue. (orig.)

  6. Relationships between brain water content and diffusion tensor imaging parameters (apparent diffusion coefficient and fractional anisotropy) in multiple sclerosis.

    Science.gov (United States)

    Sijens, Paul E; Irwan, Roy; Potze, Jan Hendrik; Mostert, Jop P; De Keyser, Jacques; Oudkerk, Matthijs

    2006-04-01

    Fifteen multiple sclerosis patients were examined by diffusion tensor imaging (DTI) to determine fractional anisotropy (FA) and apparent diffusion coefficient (ADC) in a superventricular volume of interest of 8 x 8 x 2 cm(3) containing gray matter (GM) and white matter (WM) tissue. Point resolved spectroscopy 2D-chemical shift imaging of the same volume was performed without water suppression. The water contents and DTI parameters in 64 voxels of 2 cm(3) were compared. The water content was increased in patients compared with controls (GM: 244+/-21 vs. 194+/-10 a.u.; WM: 245+/-32 vs. 190+/-11 a.u.), FA decreased (GM: 0.226+/-0.038 vs. 0.270+/-0.020; WM: 0.337+/-0.044 vs. 0.402+/-0.011) and ADC increased [GM: 1134+/-203 vs. 899+/-28 (x10(-6) mm(2)/s); WM: 901+/-138 vs. 751+/-17 (x10(-6) mm(2)/s)]. Correlations of water content with FA and ADC in WM were strong (r=-0.68, P<0.02; r=0.75; P<0.01, respectively); those in GM were weaker (r=-0.50, P<0.05; r=0.45, P<0.1, respectively). Likewise, FA and ADC were more strongly correlated in WM (r=-0.88; P<0.00001) than in GM (r=-0.69, P<0.01). The demonstrated relationship between DTI parameters and water content in multiple sclerosis patients suggests a potential for therapy monitoring in normal-appearing brain tissue.

  7. Investigations of the Response of Swimming Paramecia to Variations in their Apparent Weight

    Science.gov (United States)

    Valles, James; Jung, Ilyong; Guevorkian, Karine; Mickalide, Harry; Wagman, Michael

    2011-11-01

    There is a set of micro-organisms that are small enough that they swim at low Reynolds number and large enough that gravity exerts an influence on their behavior Many protists, like paramecia, for example, exhibit negative gravi-taxis by orienting their swimming upward and negative gravi-kinesis by increasing their propulsion when swimming against their apparent weight. It is not clear whether these responses to a very weak force (about 100 pN) are active or passive. We have developed a technique, Magnetic Force Buoyancy Variation, which enables us to vary the apparent weight of the swimmers in situ. We will describe experiments on paramecia conducted at the National High Magnetic Field Laboratory. In particular, we will describe how increasing the apparent weight induces paramecia to accumulate at upper surfaces. A simple force model suggests that this accumulation is a passive response. Supported by NSF-PHY0750360 and a grant to the NHMFL, NSF DMR-0654118.

  8. Evaluation of apparent viscosity of Para rubber latex by diffuse reflection near-infrared spectroscopy.

    Science.gov (United States)

    Sirisomboon, Panmanas; Chowbankrang, Rawiphan; Williams, Phil

    2012-05-01

    Near-infrared spectroscopy in diffuse reflection mode was used to evaluate the apparent viscosity of Para rubber field latex and concentrated latex over the wavelength range of 1100 to 2500 nm, using partial least square regression (PLSR). The model with ten principal components (PCs) developed using the raw spectra accurately predicted the apparent viscosity with correlation coefficient (r), standard error of prediction (SEP), and bias of 0.974, 8.6 cP, and -0.4 cP, respectively. The ratio of the SEP to the standard deviation (RPD) and the ratio of the SEP to the range (RER) for the prediction were 4.4 and 16.7, respectively. Therefore, the model can be used for measurement of the apparent viscosity of field latex and concentrated latex in quality assurance and process control in the factory.

  9. Apparent Deviations from Keplerian Acceleration for Stars Around the Supermassive Black Hole at the Galactic Center

    CERN Document Server

    Loeb, A

    2003-01-01

    We show that the time-dependent Doppler effect should induce measureable deviations of the time history of the projected orbit of a star around the supermassive black hole in the Galactic center (SgrA*) from the expected Keplerian history. In particular, the line-of-sight acceleration of the star generates apparent acceleration of its image along its velocity vector on the sky, even if its actual Keplerian acceleration in this direction vanishes. The excess apparent acceleration simply results from the transformation of time between the reference frames of the observer and the star. Although the excess acceleration averages to zero over a full closed orbit, it could lead to systematic offsets of a few percent in estimates of the dynamical mass or position of the black hole that rely on partially sampled orbits with pericentric distances of ~100AU. Deviations of this magnitude from apparent Keplerian dynamics of known stars should be detectable by future observations.

  10. Apparent competition and native consumers exacerbate the strong competitive effect of an exotic plant species.

    Science.gov (United States)

    Orrock, John L; Dutra, Humberto P; Marquis, Robert J; Barber, Nicholas

    2015-04-01

    Direct and indirect effects can play a key role in invasions, but experiments evaluating both are rare. We examined the roles of direct competition and apparent competition by exotic Amur honeysuckle (Lonicera maackii) by manipulating (1) L. maackii vegetation, (2) presence of L. maackii fruits, and (3) access to plants by small mammals and deer. Direct competition with L. maackii reduced the abundance and richness of native and exotic species, and native consumers significantly reduced the abundance and richness of native species. Although effects of direct competition and consumption were more pervasive, richness of native plants was also reduced through apparent competition, as small-mammal consumers reduced richness only when L. maackii fruits were present. Our experiment reveals the multiple, interactive pathways that affect the success and impact of an invasive exotic plant: exotic plants may directly benefit from reduced attack by native consumers, may directly exert strong competitive effects on native plants, and may also benefit from apparent competition.

  11. Apparent contact angle and contact angle hysteresis on liquid infused surfaces.

    Science.gov (United States)

    Semprebon, Ciro; McHale, Glen; Kusumaatmaja, Halim

    2016-12-21

    We theoretically investigate the apparent contact angle and contact angle hysteresis of a droplet placed on a liquid infused surface. We show that the apparent contact angle is not uniquely defined by material parameters, but also has a dependence on the relative size between the droplet and its surrounding wetting ridge formed by the infusing liquid. We derive a closed form expression for the contact angle in the limit of vanishing wetting ridge, and compute the correction for small but finite ridge, which corresponds to an effective line tension term. We also predict contact angle hysteresis on liquid infused surfaces generated by the pinning of the contact lines by the surface corrugations. Our analytical expressions for both the apparent contact angle and contact angle hysteresis can be interpreted as 'weighted sums' between the contact angles of the infusing liquid relative to the droplet and surrounding gas phases, where the weighting coefficients are given by ratios of the fluid surface tensions.

  12. Apparent contact angle and contact angle hysteresis on liquid infused surfaces

    Science.gov (United States)

    Semprebon, Ciro; McHale, Glen; Kusumaatmaja, Halim

    We theoretically investigate the apparent contact angle and contact angle hysteresis of a droplet placed on a liquid infused surface. We show that the apparent contact angle is not uniquely defined by material parameters, but also has a strong dependence on the relative size between the droplet and its surrounding wetting ridge formed by the infusing liquid. We derive a closed form expression for the contact angle in the limit of vanishing wetting ridge, and compute the correction for small but finite ridge, which corresponds to an effective line tension term. We also predict contact angle hysteresis on liquid infused surfaces generated by the pinning of the contact lines by the surface corrugations. Our analytical expressions for both the apparent contact angle and contact angle hysteresis can be interpreted as `weighted sums' between the contact angles of the infusing liquid relative to the droplet and surrounding gas phases, where the weighting coefficients are given by ratios of the fluid surface tensions.

  13. Elastic properties and apparent density of human edentulous maxilla and mandible.

    Science.gov (United States)

    Seong, W-J; Kim, U-K; Swift, J Q; Heo, Y-C; Hodges, J S; Ko, C-C

    2009-10-01

    The aim of this study was to determine whether elastic properties and apparent density of bone differ in different anatomical regions of the maxilla and mandible. Additional analyses assessed how elastic properties and apparent density were related. Four pairs of edentulous maxilla and mandibles were retrieved from fresh human cadavers. Bone samples from four anatomical regions (maxillary anterior, maxillary posterior, mandibular anterior, mandibular posterior) were obtained. Elastic modulus (EM) and hardness (H) were measured using the nano-indentation technique. Bone samples containing cortical and trabecular bone were used to measure composite apparent density (cAD) using Archimedes' principle. Statistical analyses used repeated measures ANOVA and Pearson correlations. Bone physical properties differed between regions of the maxilla and mandible. Generally, mandible had higher physical property measurements than maxilla. EM and H were higher in posterior than in anterior regions; the reverse was true for cAD. Posterior maxillary cAD was significantly lower than that in the three other regions.

  14. APPARENT DIGESTIBILTY EXPERIMENT WITH NILE TILAPIA (OREOCHROMIS NILOTICUS FED DIETS CONTAINING CITRULLUS LANATUS SEEDMEAL

    Directory of Open Access Journals (Sweden)

    Wasiu Adeyemi JIMOH

    2015-12-01

    Full Text Available Apparent digestibility coefficients of nutrients in Citrullus lanatus based diets were determined for Nile tilapia (Oreochromis niloticus using AIA as marker or indicator. 150 tilapia fingerlings of average weight 6.12±0.05g were acclimatized for a week, weighed and allotted into five dietary treatments; CTR, DT2, DT3, DT4 and DT5 containing 0, 15, 30, 45 and 60% Citrullus lanatus respectively. The diets were isonitrogenous, isocaloric and isolipidic. Each treatment was replicated three times with ten fish per replicate. Fish were fed 5% body weight on two equal proportions per day. The results from the study indicated that there was no significant variation (p>0.05 in the apparent organic matter and gross energy digestibility coefficients of the diets; that there was significant (p0.05 in the apparent digestibility coefficients of nutrients (protein, energy, lipid and carbohydrates between the diets up to 30% replacement levels for tilapia.

  15. Color signal integration for color discrimination along a long-range apparent motion trajectory.

    Science.gov (United States)

    Nagai, Takehiro; Kimura, Hiroto; Nakauchi, Shigeki

    2013-01-01

    In contrast to the classical view that fundamental visual attributes such as color and motion are independently processed in the visual system (e.g. Livingstone and Hubel, 1987; Marr, 1982), recent studies have revealed various forms of cross-attribute interactions, such as averaging of color appearance along the motion trajectory of an object (Nishida et al., 2007). In this study, we investigated whether such color signal integration along a motion trajectory can be induced only by motion mechanisms having large receptive fields, without simple integration within direction-selective neurons with small receptive fields, like those in V1. The stimulus consisted of discs with long-range apparent motion along a circular trajectory. The stimulus onset asynchrony (SOA) between disc presentations controlled the strength of the apparent motion perception. We measured observers' sensitivity in detecting color modulation on the discs. The results showed that the measured sensitivity was lowest at SOAs corresponding to the strongest motion perception. This can be interpreted as follows: color signals were integrated along an apparent motion path, and this integration reduced chromatic sensitivity by averaging color signals. Another experiment that controlled apparent motion perception in a different way also supported this idea. However, this integration effect seemed to be linked to responses of motion detectors for the apparent motion stimuli, not directly to perceptual motion representation in the visual system. These results suggest that the human visual system handles color information from retinal inputs regarding moving objects based not only on a retinotopic coordinate but also on object-based coordinates, even when the moving object yields only long-range apparent motion.

  16. Geographic variation in apparent competition between native and invasive Phragmites australis.

    Science.gov (United States)

    Bhattarai, Ganesh P; Meyerson, Laura A; Cronin, James T

    2017-02-01

    Apparent competition, the negative interaction between species mediated by shared natural enemies, is thought to play an important role in shaping the structure and dynamics of natural communities. However, its importance in driving species invasions, and whether the strength of this indirect interaction varies across the latitudinal range of the invasion, has not been fully explored. We performed replicated field experiments at four sites spanning 900 km along the Atlantic Coast of the United States to assess the presence and strength of apparent competition between sympatric native and invasive lineages of Phragmites australis. Four herbivore guilds were considered: stem-feeders, leaf-miners, leaf-chewers and aphids. We also tested the hypothesis that the strength of this interaction declines with increasing latitude. Within each site, native and invasive plants of P. australis were cross-transplanted between co-occurring native and invasive patches in the same marsh habitat and herbivore damage was evaluated at the end of the growing season. Apparent competition was evident for both lineages and involved all but the leaf-chewer guild. For native plants, total aphids per plant was 296% higher and the incidence of stem-feeding and leaf-mining herbivores was 34% and 221% higher, respectively, when transplanted into invasive than native patches. These data suggest that invasive P. australis has a negative effect on native P. australis via apparent competition. Averaged among herbivore types, the indirect effects of the invasive lineage on the native lineage was 57% higher than the reverse situation, suggesting that apparent competition was asymmetric. We also found that the strength of apparent competition acting against the native lineage was comparable to the benefits to the invasive lineage from enemy release (i.e., proportionately lower mean herbivory of the invasive relative to the native taxa). Finally, we found the first evidence that the strength of

  17. Two-dimensional modeling of apparent resistivity pseudosections in the Cerro Prieto region

    Energy Technology Data Exchange (ETDEWEB)

    Vega, R.; Martinez, M.

    1981-01-01

    Using a finite-difference program (Dey, 1976) for two-dimensional modeling of apparent resistivity pseudosections obtained by different measuring arrays, four apparent resistivity pseudosections obtained at Cerro Prieto with a Schlumberger array by CFE personnel were modeled (Razo, 1978). Using geologic (Puente and de la Pena, 1978) and lithologic (Diaz, et al., 1981) data from the geothermal region, models were obtained which show clearly that, for the actual resistivity present in the zone, the information contained in the measured pseudosections is primarily due to the near-surface structure and does not show either the presence of the geothermal reservoir or the granitic basement which underlies it.

  18. Turner Syndrome and apparent absent uterus: a case report and review of the literature.

    Science.gov (United States)

    Akierman, Sarah V; Skappak, Christopher D; Girgis, Rose; Ho, Josephine

    2013-01-01

    We report on a patient who initially presented with delayed puberty and an absent uterus on imaging with ultrasound and MRI. She was subsequently diagnosed with Turner Syndrome. Turner Syndrome typically presents with early loss of ovarian function and should be considered when primary ovarian insufficiency is present with apparent absent uterus on imaging. Follow-up imaging of the apparent absent uterus post-estrogen replacement therapy is important to confirm a normal uterus. A diagnosis of an absent uterus can be psychologically traumatic for patients and families, and can have significant implications for future fertility options.

  19. Anomalous Sinking of Spheres due to Local Fluidization of Apparently Fixed Powder Beds.

    Science.gov (United States)

    Oshitani, Jun; Sasaki, Toshiki; Tsuji, Takuya; Higashida, Kyohei; Chan, Derek Y C

    2016-02-12

    The sinking of an intruder sphere into a powder bed in the apparently fixed bed regime exhibits complex behavior in the sinking rate and the final depth when the sphere density is close to the powder bed density. Evidence is adduced that the intruder sphere locally fluidizes the apparently fixed powder bed, allowing the formation of voids and percolation bubbles that facilitates spheres to sink slower but deeper than expected. By adjusting the air injection rate and the sphere-to-powder bed density ratio, this phenomenon provides the basis of a sensitive large particle separation mechanism.

  20. The generalized second law of gravitational thermodynamics on the apparent and event horizons in FRW cosmology

    Energy Technology Data Exchange (ETDEWEB)

    Karami, K; Ghaffari, S; Soltanzadeh, M M, E-mail: KKarami@uok.ac.i [Department of Physics, University of Kurdistan, Pasdaran St, Sanandaj (Iran, Islamic Republic of)

    2010-10-21

    We investigate the validity of the generalized second law (GSL) of gravitational thermodynamics on the apparent and event horizons in a non-flat Friedmann-Robertson-Walker (FRW) universe containing dark energy interacting with dark matter. We show that for the dynamical apparent horizon, the GSL is always satisfied throughout the history of the universe for any spatial curvature and it is independent of the equation of state parameter of the interacting dark energy model. On the other hand, for the cosmological event horizon, the validity of the GSL depends on the equation of state parameter of the model.

  1. Tunnelling phenomenon near an apparent horizon in two-dimensional dilaton gravity

    CERN Document Server

    Cao, Li-Ming; Peng, Yuxuan

    2016-01-01

    Based on the definition of the apparent horizon in a general two-dimensional dilaton gravity theory, we analyze the tunnelling phenomenon of the apparent horizon by using Hamilton-Jacobi method. In this theory the definition of the horizon is very different from those in higher-dimensional gravity theories. The spectrum of the radiation is obtained and the temperature of the radiation is read out from this spectrum and it satisfies the usual relationship with the surface gravity. Besides, the calculation with Parikh's null geodesic method for a simple example conforms to our result in general stationary cases.

  2. A COMPARATIVE EVALUATION OF PULMONARY PARAMETERS IN DIABETES MELLITUS PATIENTS AND NON DIABETES MELLITUS APPARENTLY HEALTHY VOLUNTEER AS CONTROL

    Directory of Open Access Journals (Sweden)

    Qazi Rais Ahmed

    2012-10-01

    Full Text Available The best early evidence of a description of the symptoms of diabetes in the world's literature is recorded in the Ebers Papyrus that Diabetes Mellitus is characterized by chronic hyperglycemia with disturbances of carbohydrate, fat, and protein metabolism result in from defects in insulin secretion, insulin action, or both which affect the respiratory system also. So we decided to study the effects of diabetes mellitus on pulmonary parameters. In this study a group of 50 apparently healthy control subject of both gender and 50 Diabetic patients of both gender were randomly selected with age ranging from 19-68 years. The Diabetic patients were matched with control group in terms of age, height, weight and BSA and BMI. Spirometry was performed on an electronic spirometer (spiro exel according to American Thoracic Society and results were compared by a student t-test (2-tailed. Diabetic patients showed a significant decrement in the Forced Vital Capacity (FVC % and Peak Expiratory Flow Rate (PEFR % relative to their matched controls. However, there were no significant difference in the Forced Expiratory Volume in one Second (FEV1% and Forced Expiratory Ratio (FEV1 / FVC % between the groups We conclude that pulmonary parameters in diabetic patients there is decrement in FVC% and PEFR%, as compared to controls. which indicate restrictive pattern of lung function impairment.

  3. Volume Regulated Channels

    DEFF Research Database (Denmark)

    Klausen, Thomas Kjær

    - serves a multitude of functions in the mammalian cell, regulating the membrane potential (Em), cell volume, protein activity and the driving force for facilitated transporters giving Cl- and Cl- channels a major potential of regulating cellular function. These functions include control of the cell cycle...... of volume perturbations evolution have developed system of channels and transporters to tightly control volume homeostasis. In the past decades evidence has been mounting, that the importance of these volume regulated channels and transporters are not restricted to the defense of cellular volume......, controlled cell death and cellular migration. Volume regulatory mechanisms has long been in focus for regulating cellular proliferation and my thesis work have been focusing on the role of Cl- channels in proliferation with specific emphasis on ICl, swell. Pharmacological blockage of the ubiquitously...

  4. Thermodynamics of Apparent Horizon and Friedmann Equations in Big Bounce Universe

    CERN Document Server

    Liu, Molin; Lv, Jianbo; Xu, Lixin

    2014-01-01

    In this paper, the thermodynamics of apparent horizon and Friedmann equations are studied in a big bounce universe typified by a non-singular big bounce, as opposed to a singular big bang. This cosmological model can describe radiation dominated early universe and matter dominated late universe in FRW model. Our calculational results show that Einstein gravitational field equations could be derived by the first law of thermodynamics and the fluid's continuity equation. The connections between thermodynamics and gravity are observed in big bounce universe. In the late stages of cold and hot universes, the apparent horizons are convergent and the time when apparent horizons begin to bounce essentially in agreement with that of universe's scalar factor. In the early stage of both cold and hot universes, we find there is only one geometry containing a 4D de Sitter universe with general state parameter. Furthermore, we also find the form of apparent horizon in early universe is strongly dependent on the extra dime...

  5. Influence of feeding various phosphorus sources on apparent digestibility of phosphorus in dairy cows

    NARCIS (Netherlands)

    Ekelund, A.; Sporndly, R.; Valk, H.; Murphy, M.

    2003-01-01

    The present investigated differences in the apparent digestibility of phosphorus (ADP) in lactating cows fed various feed materials containing organic forms of phosphorus (P) or a highly available inorganic phosphorus source. Cows milking an average of 36 kg energy corrected milk (ECM) were used in

  6. Thermal conductivity as influenced by the temperature and apparent viscosity of dairy products.

    Science.gov (United States)

    Gonçalves, B J; Pereira, C G; Lago, A M T; Gonçalves, C S; Giarola, T M O; Abreu, L R; Resende, J V

    2017-03-02

    This study aimed to evaluate the rheological behavior and thermal conductivity of dairy products, composed of the same chemical components but with different formulations, as a function of temperature. Subsequently, thermal conductivity was related to the apparent viscosity of yogurt, fermented dairy beverage, and fermented milk. Thermal conductivity measures and rheological tests were performed at 5, 10, 15, 20, and 25°C using linear probe heating and an oscillatory rheometer with concentric cylinder geometry, respectively. The results were compared with those calculated using the parallel, series, and Maxwell-Eucken models as a function of temperature, and the discrepancies in the results are discussed. Linear equations were fitted to evaluate the influence of temperature on the thermal conductivity of the dairy products. The rheological behavior, specifically apparent viscosity versus shear rate, was influenced by temperature. Herschel-Bulkley, power law, and Newton's law models were used to fit the experimental data. The Herschel-Bulkley model best described the adjustments for yogurt, the power law model did so for fermented dairy beverages, and Newton's law model did so for fermented milk and was then used to determine the rheological parameters. Fermented milk showed a Newtonian trend, whereas yogurt and fermented dairy beverage were shear thinning. Apparent viscosity was correlated with temperature by the Arrhenius equation. The formulation influenced the effective thermal conductivity. The relationship between the 2 properties was established by fixing the temperature and expressing conductivity as a function of apparent viscosity. Thermal conductivity increased with viscosity and decreased with increasing temperature.

  7. To Think or Not to Think: The Apparent Paradox of Expert Skill in Music Performance

    Science.gov (United States)

    Geeves, Andrew; McIlwain, Doris J. F.; Sutton, John; Christensen, Wayne

    2014-01-01

    Expert skill in music performance involves an apparent paradox. On stage, expert musicians are required accurately to retrieve information that has been encoded over hours of practice. Yet they must also remain open to the demands of the ever-changing situational contingencies with which they are faced during performance. To further explore this…

  8. 45 CFR 73.735-904 - Resolution of apparent or actual conflicts of interest.

    Science.gov (United States)

    2010-10-01

    ... ADMINISTRATION STANDARDS OF CONDUCT Reporting Financial Interests § 73.735-904 Resolution of apparent or actual... appropriate method of resolving such conflicts when: (1) The trust is qualified under section 202(f) of the Ethics in Government Act of 1978 (Pub. L. 95-521), as amended, and subject to the regulations of...

  9. Presence of European bat lyssavirus RNas in apparently healthy Rousettus aegyptiacus bats

    NARCIS (Netherlands)

    Wellenberg, G.J.; Audry, L.; Ronsholt, L.; Poel, van der W.H.M.; Bruschke, C.J.M.; Bourhy, H.

    2002-01-01

    Apparently healthy Rousettus aegyptiacus bats were randomly chosen from a Dutch colony naturally infected with European bat lyssavirus subgenotype 1a (EBL1a). These bats were euthanised three months after the first evidence of an EBL1a infection in the colony. EBL1a genomic and antigenomic RNAs of t

  10. Structure of Gamma-Ray Burst jets: intrinsic versus apparent properties

    CERN Document Server

    Salafia, O S; Pescalli, A; Ghirlanda, G; Nappo, F

    2015-01-01

    With this paper we introduce the concept of apparent structure of a GRB jet, as opposed to its intrinsic structure. The latter is customarily defined specifying the functions epsilon(theta) (the energy emitted per jet unit solid angle) and Gamma(theta) (the Lorentz factor of the emitting material); the apparent structure is instead defined by us as the isotropic equivalent energy E_iso(theta_v) as a function of the viewing angle theta_v. We show how to predict the apparent structure of a jet given its intrinsic structure. We find that a Gaussian intrinsic structure yields a power law apparent structure: this opens a new viewpoint on the Gaussian (which can be understood as a proxy for a realistic narrow, well collimated jet structure) as a possible candidate for a quasi-universal GRB jet structure. We show that such a model (a) is consistent with recent constraints on the observed luminosity function of GRBs; (b) implies fewer orphan afterglows with respect to the standard uniform model; (c) can break out the...

  11. The effect of interaural-time-difference fluctuations on apparent source width

    DEFF Research Database (Denmark)

    Käsbach, Johannes; May, Tobias; Oskarsdottir, Gudrun;

    2014-01-01

    For the perception of spaciousness, the temporal fluctuations of the interaural time differences (ITDs) and interaural level differences (ILDs) provide important binaural cues. One major characteristic of spatial perception is apparent source width (ASW), which describes the perceived width of a ...

  12. Detection of visual events along the apparent motion trace in patients with paranoid schizophrenia.

    Science.gov (United States)

    Sanders, Lia Lira Olivier; Muckli, Lars; de Millas, Walter; Lautenschlager, Marion; Heinz, Andreas; Kathmann, Norbert; Sterzer, Philipp

    2012-07-30

    Dysfunctional prediction in sensory processing has been suggested as a possible causal mechanism in the development of delusions in patients with schizophrenia. Previous studies in healthy subjects have shown that while the perception of apparent motion can mask visual events along the illusory motion trace, such motion masking is reduced when events are spatio-temporally compatible with the illusion, and, therefore, predictable. Here we tested the hypothesis that this specific detection advantage for predictable target stimuli on the apparent motion trace is reduced in patients with paranoid schizophrenia. Our data show that, although target detection along the illusory motion trace is generally impaired, both patients and healthy control participants detect predictable targets more often than unpredictable targets. Patients had a stronger motion masking effect when compared to controls. However, patients showed the same advantage in the detection of predictable targets as healthy control subjects. Our findings reveal stronger motion masking but intact prediction of visual events along the apparent motion trace in patients with paranoid schizophrenia and suggest that the sensory prediction mechanism underlying apparent motion is not impaired in paranoid schizophrenia.

  13. Primary School Students' Ideas Concerning the Apparent Movement of the Moon

    Science.gov (United States)

    Starakis, John; Halkia, Krystallia

    2010-01-01

    In the present study, primary school students' ideas concerning the apparent movement of the Moon are investigated. The research was carried out in five primary schools of Athens (Greece) with a sample of forty (40), fifth and sixth grade students. Semistructured interviews were used to gather scientific data and students had the opportunity to…

  14. Stewart analysis of apparently normal acid-base state in the critically ill

    NARCIS (Netherlands)

    Moviat, M.; Boogaard, M. van den; Intven, F.; Voort, P. van der; Hoeven, H. van der; Pickkers, P.

    2013-01-01

    PURPOSE: This study aimed to describe Stewart parameters in critically ill patients with an apparently normal acid-base state and to determine the incidence of mixed metabolic acid-base disorders in these patients. MATERIALS AND METHODS: We conducted a prospective, observational multicenter study of

  15. Standardization of soil apparent electrical conductivity using multi-temporal surveys across multiple production fields

    Science.gov (United States)

    Apparent soil electrical conductivity (ECa) is an efficient technique for understanding within-field variability of physical and chemical soil characteristics. Commercial devices are readily available for collecting ECa on whole fields and used broadly for crop management in precision agriculture; h...

  16. Apparent-contact-angle model at partial wetting and evaporation: Impact of surface forces

    Science.gov (United States)

    Janeček, V.; Nikolayev, V. S.

    2013-01-01

    This theoretical and numerical study deals with evaporation of a fluid wedge in contact with its pure vapor. The model describes a regime where the continuous wetting film is absent and the actual line of the triple gas-liquid-solid contact appears. A constant temperature higher than the saturation temperature is imposed at the solid substrate. The fluid flow is solved in the lubrication approximation. The introduction of the surface forces in the case of the partial wetting is discussed. The apparent contact angle (the gas-liquid interface slope far from the contact line) is studied numerically as a function of the substrate superheating, contact line velocity, and parameters related to the solid-fluid interaction (Young and microscopic contact angles, Hamaker constant, etc.). The dependence of the apparent contact angle on the substrate temperature is in agreement with existing approaches. For water, the apparent contact angle may be 20∘ larger than the Young contact angle for 1 K superheating. The effect of the surface forces on the apparent contact angle is found to be weak.

  17. Concurrent temporal stability of the apparent electrical conductivity and soil water content

    Science.gov (United States)

    Knowledge of spatio-temporal soil water content (SWC) variability within agricultural fields is useful to improve crop management. Spatial patterns of soil water contents can be characterized using the temporal stability analysis, however high density sampling is required. Soil apparent electrical c...

  18. Posttreatment Apparent Diffusion Coefficient Changes in the Periresectional Area in Patients with Glioblastoma

    NARCIS (Netherlands)

    van der Hoorn, Anouk; Yan, Jiun-Lin; Larkin, Timothy J.; Boonzaier, Natalie R.; Matys, Tomasz; Price, Stephen J.

    2016-01-01

    BACKGROUND: Although targeted by radiotherapy, recurrence in glioblastoma occurs mainly periresectionally owing to tumor infiltration. An increase in the apparent diffusion coefficient (ADC) has been shown in the large high-T2 area on magnetic resonance imaging post-treatment; however, until now ADC

  19. Liquorice-induced sodium retention. Merely an acquired condition of apparent mineralocorticoid excess? A case report.

    Science.gov (United States)

    Negro, A; Rossi, E; Regolisti, G; Perazzoli, F

    2000-01-01

    Excessive ingestion of liquorice may result in sodium retention, hypertension, hypokalemia, and suppression of renin and aldosterone. Similarities between liquorice-induced effects and congenital apparent mineralocorticoid excess have recently been emphasized, as in both conditions, reduced activity of the enzyme 11 beta-hydroxysteroid dehydrogenase type 2 allows cortisol to act as a potent mineralocorticoid. We report a case of generalized edema without any increase in blood pressure, with biochemical and hormonal features of apparent mineralocorticoid excess, in a young woman who had been ingesting substantial amounts of liquorice for several years. Liquorice-induced wide-spread edema without hypertension in our patient, as well as in a few other cases previously reported, and the more common occurrence of edema associated with hypertension challenge the current explanation of liquorice syndrome as a purely acquired apparent mineralocorticoid excess. Indeed, in both congenital apparent and true mineralocorticoid excess, edema is typically absent, as a result of the sodium escape phenomenon. As pressure-natriuresis may be an essential mechanism accounting for the sodium escape phenomenon, some component of liquorice could partially or completely oppose the circulatory response that converts liquorice-induced sodium retention into blood pressure elevation. In patients with unexplained generalized edema and hypokalemia without hypertension, liquorice ingestion should be carefully investigated and the renin-aldosterone system should be assayed.

  20. Deciding what to see: the role of intention and attention in the perception of apparent motion.

    Science.gov (United States)

    Kohler, Axel; Haddad, Leila; Singer, Wolf; Muckli, Lars

    2008-03-01

    Apparent motion is an illusory perception of movement that can be induced by alternating presentations of static objects. Already in Wertheimer's early investigation of the phenomenon [Wertheimer, M. (1912). Experimentelle Studien über das Sehen von Bewegung. Zeitschrift fur Psychologie, 61, 161-265], he mentions that voluntary attention can influence the way in which an ambiguous apparent motion display is perceived. But until now, few studies have investigated how strong the modulation of apparent motion through attention can be under different stimulus and task conditions. We used bistable motion quartets of two different sizes, where the perception of vertical and horizontal motion is equally likely. Eleven observers participated in two experiments. In Experiment 1, participants were instructed to either (a) hold the current movement direction as long as possible, (b) passively view the stimulus, or (c) switch the movement directions as quickly as possible. With the respective instructions, observers could almost double phase durations in (a) and more than halve durations in (c) relative to the passive condition. This modulation effect was stronger for the large quartets. In Experiment 2, observers' attention was diverted from the stimulus by a detection task at fixation while they still had to report their conscious perception. This manipulation prolonged dominance durations for up to 100%. The experiments reveal a high susceptibility of ambiguous apparent motion to attentional modulation. We discuss how feature- and space-based attention mechanisms might contribute to those effects.

  1. Effect of dietary carbohydrate sources on apparent nutrient digestibility of olive flounder (Paralichthys olivaceus feed

    Directory of Open Access Journals (Sweden)

    Md Mostafizur Rahman

    2016-06-01

    Full Text Available Abstract Apparent digestibility coefficients (ADCs of dry matter, crude protein, crude lipid, nitrogen-free extract, and energy in selected carbohydrate sources including wheat flour (WF, α-potato starch (PS, α-corn starch (CS, Na alginate (AL, dextrin (DEX, and carboxymethyl cellulose (CMC were determined for olive flounder. The olive flounder averaging 150 ± 8.0 g were held in 300-L tanks at a density of 30 fish per tank. Chromic oxide was used as the inert marker. Feces were collected from the flounder by a fecal collector attached to a fish rearing tank. Apparent dry matter and energy digestibilities of flounder fed WF, PS, CS, and DEX diets were significantly higher than those of fish fed AL and CMC diets. Apparent crude protein digestibility coefficients of flounder fed PS and CS diets were significantly higher than those of fish fed AL, DEX, and CMC diets. Apparent crude lipid and nitrogen-free extract digestibility coefficients of flounder fed PS and DEX diets were significantly higher than those of fish fed WF, CS, AL, and CMC diets. The present findings indicate that PS and DEX could be effectively used as dietary carbohydrate energy compared to WF, CS, AL, and CMC for olive flounder.

  2. APPARENT CROSS-FIELD SUPERSLOW PROPAGATION OF MAGNETOHYDRODYNAMIC WAVES IN SOLAR PLASMAS

    Energy Technology Data Exchange (ETDEWEB)

    Kaneko, T.; Yokoyama, T. [Department of Earth and Planetary Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033 (Japan); Goossens, M.; Doorsselaere, T. Van [Centre for Mathematical Plasma Astrophysics, Katholieke Universiteit Leuven, Celestijnenlaan 200B, Bus 2400, B-3001 Herverlee (Belgium); Soler, R.; Terradas, J. [Departament de Física, Universitat de les Illes Balears, E-07122 Palma de Mallorca (Spain); Wright, A. N., E-mail: kaneko@eps.s.u-tokyo.ac.jp [School of Mathematics and Statistics, University of St Andrews, St Andrews, KY16 9SS (United Kingdom)

    2015-10-20

    In this paper we show that the phase-mixing of continuum Alfvén waves and/or continuum slow waves in the magnetic structures of the solar atmosphere as, e.g., coronal arcades, can create the illusion of wave propagation across the magnetic field. This phenomenon could be erroneously interpreted as fast magnetosonic waves. The cross-field propagation due to the phase-mixing of continuum waves is apparent because there is no real propagation of energy across the magnetic surfaces. We investigate the continuous Alfvén and slow spectra in two-dimensional (2D) Cartesian equilibrium models with a purely poloidal magnetic field. We show that apparent superslow propagation across the magnetic surfaces in solar coronal structures is a consequence of the existence of continuum Alfvén waves and continuum slow waves that naturally live on those structures and phase-mix as time evolves. The apparent cross-field phase velocity is related to the spatial variation of the local Alfvén/slow frequency across the magnetic surfaces and is slower than the Alfvén/sound velocities for typical coronal conditions. Understanding the nature of the apparent cross-field propagation is important for the correct analysis of numerical simulations and the correct interpretation of observations.

  3. Anisotropy of the apparent resistivity variation rate near the epicentral region for strong earthquakes

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The apparent resistivity data of 11 stations observed in or near the epicentral regions for 6 strong earthquakes are processed by the normalized monthly rate method. The result show that in the medium-short and short-imminent terms of earthquake preparation the variation rate of apparent resistivity perpendicular (or near perpendicular) to the direction of maximum principal stress is greater than that parallel (or near parallel) to the direction. Such an-isotropic phenomenon is interpreted as follow: the predominant alignment of cracks containing conductive fluid in the maximum principal stress direction caused the anisotropy of the fluid migration during the dilatancy process in the late period of earthquake preparation and resulted in the anisotropy of true resistivity variation rate for rock (or solid) medium which induced the variation rate anisotropy of apparent resistivity on the ground. The study of this paper provides some seismic examples to show the apparent resistivity anisotropy which may be helpful to study the stress status in or near the source zone in the late period of earthquake preparation of strong events.

  4. A Study of the Probe Effect on the Apparent Image of Biological Atomic Force Microscopy

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The probe effect on the apparent image of biological atomic force microscopy was explored in this study, and the potential of AFM in conformational study of gene related biological processes was illustrated by the specific nanostructural information of a new antitumor drug binding to DNA.

  5. Irreversible thermodynamics of dark energy on the entropy-corrected apparent horizon

    Energy Technology Data Exchange (ETDEWEB)

    Karami, K; Sahraei, N [Department of Physics, University of Kurdistan, Pasdaran Street, Sanandaj (Iran, Islamic Republic of); Jamil, M, E-mail: KKarami@uok.ac.i, E-mail: mjamil@camp.nust.edu.p [Center for Advanced Mathematics and Physics (CAMP), National University of Sciences and Technology (NUST), Islamabad (Pakistan)

    2010-10-15

    We study the irreversible (non-equilibrium) thermodynamics of the Friedmann-Robertson-Walker (FRW) universe containing only dark energy. Using the modified entropy-area relation that is motivated by loop quantum gravity, we calculate the entropy-corrected form of the apparent horizon of the FRW universe.

  6. Estimation of soil physical properties from sensor-based soil strength and apparent electrical conductivity

    Science.gov (United States)

    Quantification of soil physical properties has traditionally been through soil sampling and laboratory analyses, which is time-, cost-, and labor-consuming, making it difficult to obtain the spatially-dense data required for precision agriculture. Soil strength and apparent electrical conductivity (...

  7. Gamow's bicycle: The Appearance of Bodies at Relativistic Speeds and Apparent Superluminal Velocities

    CERN Document Server

    Nowojewski, A

    2005-01-01

    A human creates an image basing on the information delivered by photons that arrived at his retina simultaneously. Due to finite and constant velocity of light these photons left the moving body at different times, since not all points of the body are equidistant. In other words its image represents the body as it was in several different times i.e. it is distorted and does not correspond to its real appearance. The useful experimental arrangement is set and then used to derive the general expression that transforms two-dimensional stationary shapes to their apparent forms, which could be photographed once they are set in motion. It is then used to simulate the so-called Gamow's bicycle combined out of circles and straight lines. The simulation outlines two important aspects of bike's motion: apparent distance of two points and apparent velocity which are then discussed thoroughly. It is found that the approaching body is elongated and its apparent speed is greater than its real one (under certain conditions ...

  8. Linseed dietary fibers reduce apparent digestibility of energy and fat and weight gain in growing rats

    DEFF Research Database (Denmark)

    Kristensen, M.; Knudsen, K. E. B.; Jørgensen, H.;

    2013-01-01

    Dietary fibers (DF) may affect energy balance, an effect often ascribed to the viscous nature of some water soluble DF, which affect luminal viscosity and thus multiple physiological processes. We have tested the hypothesis that viscous linseed DF reduce apparent nutrient digestibility, and limit...

  9. Volume strain within the Geysers geothermal field

    Energy Technology Data Exchange (ETDEWEB)

    Mossop, Antony [Department of Geophysics, Stanford University, Stanford, California (United States); Segall, Paul [Department of Geophysics, Stanford University, Stanford, California (United States)

    1999-12-10

    During the 1970s and 1980s. The Geysers geothermal region was rapidly developed as a site of geothermal power production. The likelihood that this could cause significant strain within the reservoir, with corresponding surface displacements, led to a series of deformation monitoring surveys. In 1973, 1975, 1977, and 1980, The Geysers region was surveyed using first-order, class I, spirit leveling. In 1994, 1995, and 1996, many of the leveling control monuments were resurveyed using high-precision Global Positioning System receivers. The two survey methods are reconciled using the GEOID96 geoid model. The displacements are inverted to determine volume strain within the reservoir. For the period 1980-1994, peak volume strains in excess of 5x10{sup -4} are imaged. There is an excellent correlation between the observed changes in reservoir steam pressures and the imaged volume strain. If reservoir pressure changes are inducing volume strain, then the reservoir quasi-static bulk modulus K must be <4.6x10{sup 9} Pa. However, seismic velocities indicate a much stiffer reservoir with K=3.4x10{sup 10} Pa. This apparent discrepancy is shown to be consistent with predicted frequency dependence in K for fractured and water-saturated rock. Inversion of surface deformation data therefore appears to be a powerful method for imaging pressure change within the body of the reservoir. Correlation between induced seismicity at The Geysers and volume strain is observed. However, earthquake distribution does not appear to have a simple relationship with volume strain rate. (c) 1999 American Geophysical Union.

  10. Precision volume measurement system.

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Erin E.; Shugard, Andrew D.

    2004-11-01

    A new precision volume measurement system based on a Kansas City Plant (KCP) design was built to support the volume measurement needs of the Gas Transfer Systems (GTS) department at Sandia National Labs (SNL) in California. An engineering study was undertaken to verify or refute KCP's claims of 0.5% accuracy. The study assesses the accuracy and precision of the system. The system uses the ideal gas law and precise pressure measurements (of low-pressure helium) in a temperature and computer controlled environment to ratio a known volume to an unknown volume.

  11. Impact of gas injection on the apparent viscosity and viscoelastic property of waste activated sewage sludge.

    Science.gov (United States)

    Bobade, Veena; Baudez, Jean Christophe; Evans, Geoffery; Eshtiaghi, Nicky

    2017-05-01

    Gas injection is known to play a major role on the particle size of the sludge, the oxygen transfer rate, as well as the mixing efficiency of membrane bioreactors and aeration basins in the waste water treatment plants. The rheological characteristics of sludge are closely related to the particle size of the sludge floc. However, particle size of sludge floc depends partly on the shear induced in the sludge and partly on physico-chemical nature of the sludge. The objective of this work is to determine the impact of gas injection on both the apparent viscosity and viscoelastic property of sludge. The apparent viscosity of sludge was investigated by two methods: in-situ and after sparging. Viscosity curves obtained by in-situ measurement showed that the apparent viscosity decreases significantly from 4000 Pa s to 10 Pa s at low shear rate range (below 10 s(-1)) with an increase in gas flow rate (0.5LPM to 3LPM); however the after sparging flow curve analysis showed that the reduction in apparent viscosity throughout the shear rate range is negligible to be displayed. Torque and displacement data at low shear rate range revealed that the obtained lower apparent viscosity in the in-situ method is not the material characteristics, but the slippage effect due to a preferred location of the bubbles close to the bob, causing an inconsistent decrease of torque and increase of displacement at low shear rate range. In linear viscoelastic regime, the elastic and viscous modulus of sludge was reduced by 33% & 25%, respectively, due to gas injection because of induced shear. The amount of induced shear measured through two different tests (creep and time sweep) were the same. The impact of this induced shear on sludge structure was also verified by microscopic images.

  12. Effect of increased methionine level on performance and apparent ileal digestibility of amino acids in ducks.

    Science.gov (United States)

    Jamroz, D; Wiliczkiewicz, A; Lemme, A; Orda, J; Skorupińska, J; Wertelecki, T

    2009-10-01

    The experiment was conducted with 960 one-day-old ducklings fed mixtures (I control - 0.28% methionine) additionally supplemented with DL-methionine (DL-Met) at amounts: 0.03% (group II), 0.07% (III), 0.12% (IV) and 0.18% (V). The performance, carcass quality and apparent ileal digestibility of amino acids as the criterions of methionine (Met) effectivity were considered. The analysis of growth and development of ducks as an effect of diversified DL-Met supplements indicate that increased content of this amino acid in the diets has not affected clearly the performance parameters. The body weight of 21-day-old ducklings was significantly affected only by the level of 0.12% of added Met in comparison to control group. On day 42, the differences among groups were negligible; only the addition of 0.12% DL-Met has increased the body weight by 2.4% when compared with control (p > 0.05). Feed conversion estimated for a period of 1-42 days has not been influenced by Met supplementation. The indistinct, however, visible tendency of better ileal amino acids' apparent digestibility (for Asp.a.,Thr, Ser, Glu, Lys) was noted in the groups fed supplemented diets. Application of 0.07% and 0.18% of DL-met, has significantly (p < 0.05) improved the coefficient of cysteine (Cys) apparent ileal digestibility; however, the improvement of Met apparent ileal digestibility has been achieved by the addition of 0.18% Met. The mortality of ducklings in the experiment was very low and varied between 3.15% (II) and 0.0% (groups I and III). In general, application of 0.12% of DL-Met to mixture containing 0.28% Met had positive effect on the productive output of birds and also improved the apparent ileal digestibility of Cys and Met.

  13. Climate control of decadal-scale increases in apparent ages of eogenetic karst spring water

    Science.gov (United States)

    Martin, Jonathan B.; Kurz, Marie J.; Khadka, Mitra B.

    2016-09-01

    Water quantity and quality in karst aquifers may depend on decadal-scale variations in recharge or withdrawal, which we hypothesize could be assessed through time-series measurements of apparent ages of spring water. We tested this hypothesis with analyses of various age tracers (3H/3He, SF6, CFC-11, CFC-12, CFC-113) and selected solute concentrations [dissolved oxygen (DO), NO3, Mg, and SO4] from 6 springs in a single spring complex (Ichetucknee springs) in northern Florida over a 16-yr period. These springs fall into two groups that reflect shallow short (Group 1) and deep long (Group 2) flow paths. Some tracer concentrations are altered, with CFC-12 and CFC-113 concentrations yielding the most robust apparent ages. These tracers show a 10-20-yr monotonic increase in apparent age from 1997 to 2013, including the flood recession that followed Tropical Storm Debby in mid-2012. This increase in age indicates most water discharged during the study period recharged the aquifer within a few years of 1973 for Group 2 springs and 1980 for Group 1 springs. Inverse correlations between apparent age and DO and NO3 concentrations reflect reduced redox state in older water. Positive correlations between apparent age and Mg and SO4 concentrations reflect increased water-rock reactions. Concentrated recharge in the decade around 1975 resulted from nearly 2 m of rain in excess of the monthly average that fell between 1960 and 2014, followed by a nearly 4 m deficit to 2014. This excess rain coincided with two major El Niño events during the maximum cool phase in the Atlantic Multidecadal Oscillation. Although regional water withdrawal increased nearly 5-fold between 1980 and 2005, withdrawals represent only 2-5% of Ichetucknee River flow and are less important than decadal-long variations in precipitation. These results suggest that groundwater management should consider climate cycles as predictive tools for future water resources.

  14. Statistical effects related to low numbers of reacting molecules analyzed for a reversible association reaction A + B = C in ideally dispersed systems: An apparent violation of the law of mass action.

    Science.gov (United States)

    Szymanski, R; Sosnowski, S; Maślanka, Ł

    2016-03-28

    Theoretical analysis and computer simulations (Monte Carlo and numerical integration of differential equations) show that the statistical effect of a small number of reacting molecules depends on a way the molecules are distributed among the small volume nano-reactors (droplets in this study). A simple reversible association A + B = C was chosen as a model reaction, enabling to observe both thermodynamic (apparent equilibrium constant) and kinetic effects of a small number of reactant molecules. When substrates are distributed uniformly among droplets, all containing the same equal number of substrate molecules, the apparent equilibrium constant of the association is higher than the chemical one (observed in a macroscopic-large volume system). The average rate of the association, being initially independent of the numbers of molecules, becomes (at higher conversions) higher than that in a macroscopic system: the lower the number of substrate molecules in a droplet, the higher is the rate. This results in the correspondingly higher apparent equilibrium constant. A quite opposite behavior is observed when reactant molecules are distributed randomly among droplets: the apparent association rate and equilibrium constants are lower than those observed in large volume systems, being the lower, the lower is the average number of reacting molecules in a droplet. The random distribution of reactant molecules corresponds to ideal (equal sizes of droplets) dispersing of a reaction mixture. Our simulations have shown that when the equilibrated large volume system is dispersed, the resulting droplet system is already at equilibrium and no changes of proportions of droplets differing in reactant compositions can be observed upon prolongation of the reaction time.

  15. Event and Apparent Horizon Finders for 3+1 Numerical Relativity

    Directory of Open Access Journals (Sweden)

    Thornburg Jonathan

    2007-06-01

    Full Text Available Event and apparent horizons are key diagnostics for the presence and properties of black holes. In this article I review numerical algorithms and codes for finding event and apparent horizons in numerically-computed spacetimes, focusing on calculations done using the 3+1 ADM formalism. The event horizon of an asymptotically-flat spacetime is the boundary between those events from which a future-pointing null geodesic can reach future null infinity and those events from which no such geodesic exists. The event horizon is a (continuous null surface in spacetime. The event horizon is defined nonlocally in time: it is a global property of the entire spacetime and must be found in a separate post-processing phase after all (or at least the nonstationary part of spacetime has been numerically computed.There are three basic algorithms for finding event horizons, based on integrating null geodesics forwards in time, integrating null geodesics backwards in time, and integrating null surfaces backwards in time. The last of these is generally the most efficient and accurate.In contrast to an event horizon, an apparent horizon is defined locally in time in a spacelike slice and depends only on data in that slice, so it can be (and usually is found during the numerical computation of a spacetime. A marginally outer trapped surface (MOTS in a slice is a smooth closed 2-surface whose future-pointing outgoing null geodesics have zero expansion Theta. An apparent horizon is then defined as a MOTS not contained in any other MOTS. The MOTS condition is a nonlinear elliptic partial differential equation (PDE for the surface shape, containing the ADM 3-metric, its spatial derivatives, and the extrinsic curvature as coefficients. Most “apparent horizon” finders actually find MOTSs.There are a large number of apparent horizon finding algorithms, with differing trade-offs between speed, robustness, accuracy, and ease of programming. In axisymmetry, shooting

  16. Kidney Function Decline and Apparent Treatment-Resistant Hypertension in the Elderly.

    Directory of Open Access Journals (Sweden)

    Jean Kaboré

    Full Text Available Cross-sectional studies show a strong association between chronic kidney disease and apparent treatment-resistant hypertension, but the longitudinal association of the rate of kidney function decline with the risk of resistant hypertension is unknown.The population-based Three-City included 8,695 participants older than 65 years, 4265 of them treated for hypertension. We estimated the odds ratios (OR of new-onset apparent treatment-resistant hypertension, defined as blood pressure ≥ 140/90 mmHg despite use of 3 antihypertensive drug classes or ≥ 4 classes regardless of blood pressure, associated with the mean estimated glomerular filtration rate (eGFR level and its rate of decline over 4 years, compared with both controlled hypertension and uncontrolled nonresistant hypertension with ≤ 2 drugs. GFR was estimated with three different equations.Baseline prevalence of apparent treatment-resistant hypertension and of controlled and uncontrolled nonresistant hypertension, were 6.5%, 62.3% and 31.2%, respectively. During follow-up, 162 participants developed apparent treatment-resistant hypertension. Mean eGFR decline with the MDRD equation was 1.5±2.9 mL/min/1.73 m² per year: 27.7% of the participants had an eGFR ≥3 and 10.1% ≥ 5 mL/min/1.73 m² per year. After adjusting for age, sex, obesity, diabetes, and cardiovascular history, the ORs for new-onset apparent treatment-resistant hypertension associated with a mean eGFR level, per 15 mL/min/1.73 m² drop, were 1.23 [95% confidence interval 0.91-1.64] compared to controlled hypertension and 1.10 [0.83-1.45] compared to uncontrolled nonresistant hypertension; ORs associated with a decline rate ≥ 3 mL/min/1.73 m² per year were 1.89 [1.09-3.29] and 1.99 [1.19-3.35], respectively. Similar results were obtained when we estimated GFR with the CKDEPI and the BIS1 equations. ORs tended to be higher for an eGFR decline rate ≥ 5 mL/min/1.73 m² per year.The speed of kidney function decline is

  17. Variable volume combustor

    Energy Technology Data Exchange (ETDEWEB)

    Ostebee, Heath Michael; Ziminsky, Willy Steve; Johnson, Thomas Edward; Keener, Christopher Paul

    2017-01-17

    The present application provides a variable volume combustor for use with a gas turbine engine. The variable volume combustor may include a liner, a number of micro-mixer fuel nozzles positioned within the liner, and a linear actuator so as to maneuver the micro-mixer fuel nozzles axially along the liner.

  18. Motivation to hide emotion and children's understanding of the distinction between real and apparent emotions.

    Science.gov (United States)

    Gosselin, Pierre; Warren, Madeleine; Diotte, Michèle

    2002-12-01

    The authors investigated the extent to which children's understanding of the distinction between real and apparent emotions varied according to the motivation to hide emotions. Children, aged 6-7 and 10-11 years, were read stories designed to elicit either prosocial or self-protective motivated display rules and were asked to predict the facial expressions the protagonists would make to hide felt emotions. Children were found to understand the distinction between real and apparent emotions very well, independently of the type of motivation. Contrary to predictions, boys understood this distinction better than did girls when the motivation to hide positive emotions was prosocial. Children perceived neutralization as the most appropriate strategy to hide felt emotions, followed by masking.

  19. The apparent diffusion coefficient of water in gray and white matter of the infant brain

    DEFF Research Database (Denmark)

    Toft, P B; Leth, H; Peitersen, Birgit;

    1996-01-01

    PURPOSE: The purpose was to obtain normal values of the apparent diffusion coefficient (ADC) in the infant brain and to compare ADC maps with T1- and T2-weighted images. METHOD: Diffusion was measured in nine infants with an ECG-gated SE sequence compensated for first-order motion. One axial slic...... of the ADC increased with age and approached 1 at the age of 30 weeks. CONCLUSION: ADC maps add information to the T1 and T2 images about the size and course of unmyelinated as well as myelinated tracts in the immature brain.......PURPOSE: The purpose was to obtain normal values of the apparent diffusion coefficient (ADC) in the infant brain and to compare ADC maps with T1- and T2-weighted images. METHOD: Diffusion was measured in nine infants with an ECG-gated SE sequence compensated for first-order motion. One axial slice...

  20. Apparent competition drives community-wide parasitism rates and changes in host abundance across ecosystem boundaries.

    Science.gov (United States)

    Frost, Carol M; Peralta, Guadalupe; Rand, Tatyana A; Didham, Raphael K; Varsani, Arvind; Tylianakis, Jason M

    2016-08-31

    Species have strong indirect effects on others, and predicting these effects is a central challenge in ecology. Prey species sharing an enemy (predator or parasitoid) can be linked by apparent competition, but it is unknown whether this process is strong enough to be a community-wide structuring mechanism that could be used to predict future states of diverse food webs. Whether species abundances are spatially coupled by enemy movement across different habitats is also untested. Here, using a field experiment, we show that predicted apparent competitive effects between species, mediated via shared parasitoids, can significantly explain future parasitism rates and herbivore abundances. These predictions are successful even across edges between natural and managed forests, following experimental reduction of herbivore densities by aerial spraying of insecticide over 20 hectares. This result shows that trophic indirect effects propagate across networks and habitats in important, predictable ways, with implications for landscape planning, invasion biology and biological control.

  1. Line tension and reduction of apparent contact angle associated with electric double layers

    CERN Document Server

    Dörr, Aaron

    2014-01-01

    The line tension of an electrolyte wetting a non-polar substrate is computed analytically and numerically. The results show that, depending on the value of the apparent contact angle, positive or negative line tension values may be obtained. Furthermore, a significant difference between Young's contact angle and the apparent contact angle measured several Debye lengths remote from the three-phase contact line occurs. When applying the results to water wetting highly charged surfaces, line tension values of the same order of magnitude as found in recent experiments can be achieved. Therefore, the theory presented may contribute to the understanding of line tension measurements and points to the importance of the electrostatic line tension. Being strongly dependent on the interfacial charge density, electrostatic line tension is found to be tunable via the pH value of the involved electrolyte. As a practical consequence, the stability of nanoparticles adsorbed at fluid-fluid interfaces is predicted to be depend...

  2. Pseudomagnitudes and Differential Surface Brightness: Application to the apparent diameter of stars

    CERN Document Server

    Chelli, Alain; Bourgès, Laurent; Mella, Guillaume; Lafrasse, Sylvain; Bonneau, Daniel; Chesneau, Olivier

    2016-01-01

    The diameter of a star is a major observable that serves to test the validity of stellar structure theories. It is also a difficult observable that is mostly obtained with indirect methods since the stars are so remote. Today only ~600 apparent star diameters have been measured by direct methods: optical interferometry and lunar occultations. Accurate star diameters are now required in the new field of exoplanet studies, since they condition the planets' sizes in transit observations, and recent publications illustrate a visible renewal of interest in this topic. Our analysis is based on the modeling of the relationship between measured angular diameters and photometries. It makes use of two new reddening-free concepts: a distance indicator called pseudomagnitude, and a quasi-experimental observable that is independent of distance and specific to each star, called the differential surface brightness (DSB). The use of all the published measurements of apparent diameters that have been collected so far, and a c...

  3. Improved measurements of the apparent resistivity for small depths in Vertical Electrical Soundings

    Science.gov (United States)

    Faleiro, E.; Asensio, G.; Moreno, J.

    2016-08-01

    In this work, a full simulation of a Vertical Electrical Sounding of a multilayer soil using a Wenner array is performed when both the active and the measurement electrodes consist of bare rod length L buried vertically at ground level. The apparent resistivity is calculated for a wide range of values of the separation between the electrodes using the values of the potential between the measuring electrode and a proposed function that characterizes the behavior of the electrodes used which substantially improves the measurements for small depths. The results allow comparing the values of apparent resistivity obtained by known calculation expressions with the results found by using a characteristic function of the electrodes, which is proposed in this paper. In order to obtain a complete vertical sounding of the soil, the convenience of using adapted methods to the type of electrode used in the sounding is discussed.

  4. A simple expression for the apparent reaction rate of large wood char gasification with steam.

    Science.gov (United States)

    Umeki, Kentaro; Roh, Seon-Ah; Min, Tai-Jin; Namioka, Tomoaki; Yoshikawa, Kunio

    2010-06-01

    A simple expression for the apparent reaction rate of large wood char gasification with steam is proposed. Large char samples were gasified under steam atmosphere using a thermo-balance reactor. The apparent reaction rate was expressed as the product of the intrinsic rate and the effective factor. The effective factor was modified to include the effect of change in char diameter and intrinsic reaction rate during the reaction. Assuming uniform conversion ratio throughout a particle, the simplified reaction scheme was divided into three stages. In the initial stage, the local conversion ratio increases without particle shrinkage. In the middle stage, the particle shrinks following the shrinking core model without change in the local conversion ratio. In the final stage, the local conversion ratio increases without particle shrinkage. The validity of the modified effective value was confirmed by comparison with experimental results.

  5. A Non-Mainstream Viewpoint on Apparent Superluminal Phenomena in AGN Jet

    Indian Academy of Sciences (India)

    Wen-Po Liu; Li-Yan Liu; Chun-Cheng Wang

    2014-09-01

    The group velocity of light in material around the AGN jet is acquiescently one ( as a unit), but this is only a hypothesis. Here, we re-derive apparent superluminal and Doppler formulas for the general case (it is assumed that the group velocity of light in the uniform and isotropic medium around a jet (a beaming model) is not necessarily equal to one, e.g., Araudo et al. (2010) thought that there may be dense clouds around AGN jet base), and show that the group velocity of light close to one could seriously affect apparent superluminal phenomena and Doppler effect in the AGN jet (when the viewing angle and Lorentz factor take some appropriate values).

  6. Measurement of Apparent Thermal Conductivity of JSC-1A Under Ambient Pressure

    Science.gov (United States)

    Yuan, Zeng-Guang; Kleinhenz, Julie E.

    2011-01-01

    The apparent thermal conductivity of JSC-1A lunar regolith simulant was measured experimentally using a cylindrical apparatus. Eleven thermocouples were embedded in the simulant bed to obtain the steady state temperature distribution at various radial, axial, and azimuthal locations. The high aspect ratio of a cylindrical geometry was proven to provide a one-dimensional, axisymmetric temperature field. A test series was performed at atmospheric pressure with varying heat fluxes. The radial temperature distribution in each test fit a logarithmic function, indicating a constant thermal conductivity throughout the soil bed. However, thermal conductivity was not constant between tests at different heat fluxes. This variation is attributed to stresses created by thermal expansion of the simulant particles against the rigid chamber wall. Under stress-free conditions (20 deg C), the data suggest a temperature independent apparent conductivity of 0.1961 +/- 0.0070 W/m/ deg C

  7. Experimental evaluation of apparent tissue surface tension based on the exact solution of the Laplace equation

    Science.gov (United States)

    Norotte, C.; Marga, F.; Neagu, A.; Kosztin, I.; Forgacs, G.

    2008-02-01

    The notion of apparent tissue surface tension offered a systematic way to interpret certain morphogenetic processes in early development. It also allowed deducing quantitative information on cellular and molecular parameters that is otherwise difficult to obtain. To accurately determine such tensions we combined novel experiments with the exact solution of the Laplace equation for the profile of a liquid drop under the employed experimental conditions and used the exact solution to evaluate data collected on tissues. Our results confirm that tissues composed of adhesive and motile cells indeed can be characterized in terms of well-defined apparent surface tension. Our experimental technique presents a way to measure liquid interfacial tensions under conditions when known methods fail.

  8. Prediction of Apparent Equivalent Thickness Using the Spontaneous Potential Method and Its Application to Oilfield Development

    Institute of Scientific and Technical Information of China (English)

    Wang Junheng; Pan Zhuping; Sun Shuwen; Guo Lei

    2007-01-01

    The upper spontaneous potential produced by oil and gas accumulation is of a stable potential field, and its intensity is directly proportional to the content of the source and inversely proportional to the radius apart from the source. Theoretical research and practical results show that anomalies of spontaneous potential can indicate oil-bearing sandstone bodies and locate the areas of oil and gas accumulation. In oil areas which have fewer reservoir beds, the petroleum reservoir thickness can be predicted by determining the linear relationship between potential intensity and apparent apparent equivalent thickness can be predicted by the linear equation h= -0.19x+0.74. On the basis of geological research, we use the spontaneous potential method to predict the equivalent thickness, helping in the selection of the most appropriate drill sites to enhance the probability of successful well boring so as to serve the next round development of the oilfield.

  9. Influence of surface conductivity on the apparent zeta potential of calcite

    CERN Document Server

    Li, Shuai; Heberling, Frank; Devau, Nicolas; Jougnot, Damien; Chiaberge, Christophe

    2016-01-01

    Zeta potential is a physicochemical parameter of particular importance in describing the surface electrical properties of charged porous media. However, the zeta potential of calcite is still poorly known because of the difficulty to interpret streaming potential experiments. The Helmholtz-Smoluchowski (HS) equation is widely used to estimate the apparent zeta potential from these experiments. However, this equation neglects the influence of surface conductivity on streaming potential. We present streaming potential and electrical conductivity measurements on a calcite powder in contact with an aqueous NaCl electrolyte. Our streaming potential model corrects the apparent zeta potential of calcite by accounting for the influence of surface conductivity and flow regime. We show that the HS equation seriously underestimates the zeta potential of calcite, particularly when the electrolyte is diluted (ionic strength < 0.01 M) because of calcite surface conductivity. The basic Stern model successfully predicted ...

  10. Digestion, absorption and utilization of single-cell protein by the preruminant calf. The true digestibility of milk and bacterial protein and the apparent digestibility and utilization of their constituent amino acids.

    Science.gov (United States)

    Sedgman, C A; Roy, J H; Thomas, J; Stobo, I J; Ganderton, P

    1985-07-01

    Two experiments of Latin square design were made, each with four Friesian bull calves fitted with re-entrant duodenal and ileal cannulas at 4-10 d of age. The calves were used to study the effect of giving milk-substitutes containing 0, 300, 500 and 700 g bacterial protein (Pruteen)/kg total protein on apparent digestibility of nitrogen fractions and amino acids and true digestibility of 3H-labelled milk protein and 35S-labelled bacterial protein in the small intestine. A third experiment of Latin square design with four intact Friesian calves was used to measure apparent digestibility of nutrients throughout the alimentary tract and retention of N, calcium and phosphorus. At the duodenum, volume of outflow, its pH, and outflow of total-N(TN), protein-N (PN) and non-protein-N (NPN) decreased with time after feeding. At the ileum, volume of outflow and TN outflow were unaffected by time after feeding but PN outflow decreased; NPN outflow at the ileum increased to a maximum 6 h after feeding and then declined. Increased inclusion of Pruteen did not affect the volume of outflow at the duodenum or ileum, but duodenal PN outflow increased. At the ileum, pH values were lower and TN, PN and NPN outflows were higher with increasing concentration of Pruteen in the diet. Apparent digestibility in the small intestine tended to decrease with greater amounts of Pruteen, but was only significant for NPN. Apparent digestibility from mouth to ileum significantly decreased for TN and PN as Pruteen inclusion increased. Amino acid concentration in duodenal outflow, with the exception of that of arginine, reflected intake. The total amount of each amino acid in ileal outflow increased and the apparent digestibility of most amino acids decreased with greater amounts of Pruteen in the diet. Apparent digestibility of nucleic acid-N from Pruteen was very high. True digestibility in the small intestine and between mouth and ileum of 3H-labelled milk protein was high and did not differ

  11. Kinetic evidence of an apparent negative activation enthalpy in an organocatalytic process

    KAUST Repository

    Han, Xiao

    2013-08-30

    A combined kinetic and computational study on our tryptophan-based bifunctional thiourea catalyzed asymmetric Mannich reactions reveals an apparent negative activation enthalpy. The formation of the pre-transition state complex has been unambiguously confirmed and these observations provide an experimental support for the formation of multiple hydrogen bonding network between the substrates and the catalyst. Such interactions allow the creation of a binding cavity, a key factor to install high enantioselectivity.

  12. Apparent Life-Threatening Event following Maternal Use of Temazepam during Labour

    Directory of Open Access Journals (Sweden)

    L. Damen

    2014-01-01

    Full Text Available Benzodiazepines are one of the most frequently prescribed psychotropic drugs during pregnancy. Despite the fact that these drugs have been in use for a long time, there is still debate about the safety for the developing fetus and neonate. We present a case of a newborn with an apparent life-threatening event shortly after birth following maternal temazepam use during labour and advise to be reserved in prescribing any dose of any kind of benzodiazepine during labour.

  13. Exclusion and spatial segregation in the apparent competition between two hosts sharing macroparasites.

    Science.gov (United States)

    Manica, Mattia; Rosà, Roberto; Pugliese, Andrea; Bolzoni, Luca

    2013-06-01

    In this paper we investigate the spatial dynamics of a deterministic model describing two host species that partially share a common spatial domain, experiencing apparent competition mediated by macroparasites. The aim of this work is to understand the mechanisms underlying apparent competition processes in a spatially structured environment, which have been generally overlooked up to now. First, we analyse the behaviour of a single-host macroparasite partial differential equation (PDE) model, both in the cases of uniform or spatially-dependent vital rates of the host, focusing on the role of spatial diffusion on parasite persistence and host abundance. We obtained the threshold condition for parasite persistence, and (in contrast to what occurs in reaction-diffusion models for an isolated population) we found that, in the case of spatially-dependent vital rates, increasing the host diffusion coefficient results in an increase of the overall host population. Then, a PDE model featuring spatial diffusion and apparent competition mediated via shared macroparasites between two species is analysed in order to understand the role of spatial heterogeneity in host coexistence. We assumed a partial overlap among the habitats of the two species and found that the shared parasites could cause, depending on the values of the diffusion coefficients and differences in induced mortality among host species, a decrease of the realized habitat and, eventually, the extinction of the species less tolerant to parasite infection. This shows that the presence of regulating parasites complicates the effect of dispersal on population dynamics and that the dynamics of apparent competition cannot be adequately understood from spatially-independent models.

  14. Promotive effects of resistant maltodextrin on apparent absorption of calcium, magnesium, iron and zinc in rats

    OpenAIRE

    Miyazato, Shoko; Nakagawa, Chie; Kishimoto, Yuka; TAGAMI, Hiroyuki; Hara, Hiroshi

    2010-01-01

    Background: It has been reported that low-viscous and fermentable dietary fiber and nondigestible oligosaccharides enhance mineral absorption. Resistant maltodextrin, nonviscous, fermentable and soluble source of dietary fiber, has several physiological functions. However, influence of resistant maltodextrin on mineral absorption is unclear. Aim of the study: We conducted balance studies in rats to investigate effects of resistant maltodextrin and hydrogenated resistant maltodextrin on appare...

  15. Promotive effects of resistant maltodextrin on apparent absorption of calcium, magnesium, iron and zinc in rats

    OpenAIRE

    Miyazato, Shoko; Nakagawa, Chie; Kishimoto, Yuka; TAGAMI, Hiroyuki; Hara, Hiroshi

    2009-01-01

    Background It has been reported that low-viscous and fermentable dietary fiber and nondigestible oligosaccharides enhance mineral absorption. Resistant maltodextrin, nonviscous, fermentable and soluble source of dietary fiber, has several physiological functions. However, influence of resistant maltodextrin on mineral absorption is unclear. Aim of the study We conducted balance studies in rats to investigate effects of resistant maltodextrin and hydrogenated resistant maltodextrin on apparent...

  16. Effect of oral versus intramuscular Vitamin D replacement in apparently healthy adults with Vitamin D deficiency

    OpenAIRE

    Nitin Gupta; Khalid J Farooqui; Chandar M Batra; Raman K Marwaha; Ambrish Mithal

    2017-01-01

    Context: A number of controversies exist regarding appropriate treatment strategy for Vitamin D deficiency. Aims: The aim of this study was to investigate the efficacy of equivalent doses of oral cholecalciferol (60,000 IU weekly for 5 weeks) versus intramuscular (IM) cholecalciferol (300,000 IU) in correcting Vitamin D deficiency in apparently healthy volunteers working in a hospital. Settings and Design: Prospective randomized open-label single institution study. Subjects and Methods: This ...

  17. Diagnosis and management of “an apparent mechanical” femoral mononeuropathy: a case study

    OpenAIRE

    Desmarais, Ariane; Descarreaux, Martin

    2007-01-01

    This report describes an apparent case of femoral nerve mononeuropathy in a 58-year-old equestrian due to mechanical stress. A woman presented at a chiropractic office complaining of right buttock pain radiating to the right groin and knee. A treatment plan, consisting of chiropractic adjustments in addition to stretching and myofascial therapy, was initiated. The goal was to reduce pain and inflammation in the sacroiliac articulation by restoring normal biomechanical function. A rehabilitati...

  18. Discrete fragment model for apparent formation constants of actinide ions with humic substances

    Energy Technology Data Exchange (ETDEWEB)

    Sasaki, Takayuki; Yoshida, Hatsumi; Aoyama, Shunsuke; Kobayashi, Taishi; Takagi, Ikuji [Kyoto Univ. (Japan). Dept. of Nuclear Engineering; Moriyama, Hirotake [Kyoto Univ., Osaka (Japan). Research Reactor Inst.

    2015-09-01

    A semi-empirical thermodynamic model was applied to estimate the apparent formation constants of actinide ions, i.e., Th(IV), Pu(IV) and Np(V), with humic substances (HSs), including humic and fulvic acids, over a wide range of solution conditions, i.e., pH, ionic strength, and HS and metal concentrations. The hypothetical HSs consist of humic and fulvic acids with nine types of simple organic ligands, which include aromatic and aliphatic carboxyl groups and phenol groups, as binding sites. The abundance of each binding site in the hypothetical HSs was determined via a fitting analysis using an acid-dissociation dataset for several HSs. To determine the apparent formation constant of a given metal ion with HSs, 54 specific binding sites were considered, including nine monodentate sites (1:1 metal/ligand complexes) and 45 bidentate sites (1:2 metal/ligand complexes). The formation constant of each monodentate binding was determined from the experimental data, while those of the bidentate bindings were determined by considering two monodentate bindings and the chelating effect, for which one of the adjustable parameters was introduced in the model. Introduction of the other parameter, which is related to the fraction of monodentate to bidentate sites (i.e., the heterogeneity), afforded the parameter values with good correlation with the apparent formation constant data. The present model with adjusted parameter values well reproduced the experimental apparent complex formation constants for actinide ion interaction with HSs in a wide range of solution conditions except for those obtained at trace concentrations.

  19. Moving a hand-held object: Reconstruction of referent coordinate and apparent stiffness trajectories.

    Science.gov (United States)

    Ambike, S; Zhou, T; Zatsiorsky, V M; Latash, M L

    2015-07-01

    This study used the framework of the referent configuration hypothesis and slow changes in the external conditions during vertical oscillation of a hand-held object to infer the characteristics of hypothetical control variables. The study had two main objectives: (1) to show that hypothetical control variables, namely, referent coordinates and apparent stiffness of vertical hand position and grip force can be measured in an experiment; and (2) to establish relation(s) between these control variables that yield the classic grip-force-load-force coupling. Healthy subjects gripped a handle and performed vertical oscillations between visual targets at one of five metronome-prescribed frequencies. A HapticMaster robot was used to induce slow changes in the vertical force applied to the handle, while the size of the handle was changed slowly leading to changes in the grip aperture. The subjects were instructed not to react to possible changes in the external forces. A linear, second-order model was used to reconstruct the referent coordinate and apparent stiffness values for each phase of the vertical oscillation cycle using across-cycle regressions. The reconstructed time profiles of the referent coordinates and apparent stiffness showed consistent trends across subjects and movement frequencies. To validate the method, these values were used to predict the vertical force and the grip force applied to the handle for movement cycles that were not utilized in the reconstruction process. Analysis of the coupling between the four variables, two referent coordinates and two apparent stiffness values, revealed a single strong constraint reflecting the coupling between the grip force and vertical force. We view these data as providing experimental support for the idea of controlling natural, multi-muscle actions with shifts in a low-dimensional set of referent coordinates.

  20. Subsidies to predators, apparent competition and the phylogenetic structure of prey communities.

    Science.gov (United States)

    Helmus, Matthew R; Mercado-Silva, Norman; Vander Zanden, M Jake

    2013-11-01

    Ecosystems are fragmented by natural and anthropogenic processes that affect organism movement and ecosystem dynamics. When a fragmentation restricts predator but not prey movement, then the prey produced on one side of an ecosystem edge can subsidize predators on the other side. When prey flux is high, predator density on the receiving side increases above that possible by in situ prey productivity, and when low, the formerly subsidized predators can impose strong top-down control of in situ prey--in situ prey experience apparent competition from the subsidy. If predators feed on some evolutionary clades of in situ prey over others, then subsidy-derived apparent competition will induce phylogenetic structure in prey composition. Dams fragment the serial nature of river ecosystems by prohibiting movement of organisms and restricting flowing water. In the river tailwater just below a large central Mexican dam, fish density was high and fish gorged on reservoir-derived zooplankton. When the dam was closed, water flow and the zooplankton subsidy ceased, densely packed pools of fish formed, fish switched to feed on in situ prey, and the tailwater macroinvertebrate community was phylogenetic structured. We derived expectations of structure from trait-based community assembly models based on macroinvertebrate body size, tolerance to anthropogenic disturbance, and fish-diet selectivity. The diet-selectivity model best fit the observed tailwater phylogenetic structure. Thus, apparent competition from subsidies phylogenetically structures prey communities, and serial variation in phylogenetic community structure can be indicative of fragmentation in formerly continuous ecosystems.

  1. An Apparent Descriptive Method for Judging the Synchronization of Rotation of Binary Stars

    Indian Academy of Sciences (India)

    Li Lin-sen

    2004-09-01

    The problem of the synchronous rotation of binary stars is judged by using a synchronous parameter introduced in an apparent descriptive method. The synchronous parameter is defined as the ratio of the rotational period to the orbital period. The author suggests several apparent phenomenal descriptive methods for judging the synchronization of rotation of binary stars. The first method is applicable when the orbital inclination is well-known. The synchronous parameter is defined by using the orbital inclination and the observable rotational velocity (1,2 sin ). The method is mainly suitable for eclipsing binary stars. Several others are suggested for the cases when the orbital inclination is unknown. The synchronous parameters are defined by using 1,2 sin , 1,2 sin3 , the mass function () and semi-amplitudes of the velocity curve, 1,2 given in catalogue of parameters of spectroscopic binary systems and (1,2 sin ). These methods are suitable for spectroscopic binary stars including those that show eclipses and visual binary stars concurrently. The synchronous parameters for fifty-five components in thirty binary systems are calculated by using several methods. The numerical results are listed in Tables 1 and 2. The statistical results are listed in Table 3. In addition, several apparent descriptive methods are discussed.

  2. THE APPARENT VISCOSITY OF SEMI-SOLID AZ91D ALLOY AT STEADY STATE

    Institute of Scientific and Technical Information of China (English)

    Z.S. Zhen; W.M. Mao; S.J. Yan; A.M. Zhao; C.L. CuI; X.Y. Zhong

    2002-01-01

    The Rheological behavior of semi-solid AZ91D at steady state is studied using a Couettetype viscometer in the present paper. The results show that the apparent viscosity ofsemi-solid AZ91D at the steady state increases with the solid fraction increasing, andgoes up sharply when the solid fraction reaches a certain value, which is called criticalfraction. In addition, the apparent viscosity of semi-solid AZ91D at the steady statetakes on a distinct downtrend with the shearing rate increasing, which indicates astrong shear thinning property. In addition, the critical solid fraction becomes higherunder larger shearing rate, owing to the more globular shape of the solid particles.Based on the present experiment results, an empirical equation is built as that, relatingthe steady state apparent viscosity of semi-solid AZ91D with the solid fraction fs andshearing rate γ at the same time: ηapp=10. 74exp(6.95fs)γ-0.86.

  3. The apparent elastic modulus of the juxtarticular subchondral bone of the femoral head.

    Science.gov (United States)

    Brown, T D; Vrahas, M S

    1984-01-01

    An experiment was undertaken to obtain approximate values for the intrinsic elastic modulus of subchondral bone. Shallow spherical caps, with uniform and incrementally controlled thickness, were machined from subchondral bone in the weight-bearing regions of 11 fresh-frozen normal femoral head autopsy specimens. Under application of polar point loads, the measured deflections were compared with a corresponding analytical shell solution, thus allowing back-calculation of the apparent modulus. Analogous tests were performed on similarly shaped specimens of stock Plexiglas of known modulus in order to estimate the precision of the testing method. The aggregate results for subchondral bone showed that its intrinsic stiffness correlated inversely with nominal shell thickness, but even the thinnest (1.0 mm thick) of these shells had an apparent modulus (mean = 1.372 GN/m2, SD = 414 MN/m2) well below that generally accepted for "pure" cortical bone (about 14 GN/m2). This stiffness deficit was very likely due to the presence of histologically evident marrow spaces. However, the low apparent modulus values measured in this study may not be fully representative of complex in vivo behavior, because in the testing of excised shells there is no radial compressive stress transfer to underlying cancellous bone.

  4. Correlation functions quantify super-resolution images and estimate apparent clustering due to over-counting

    CERN Document Server

    Veatch, Sarah; Shelby, Sarah; Chiang, Ethan; Holowka, David; Baird, Barbara

    2011-01-01

    We present an analytical method to quantify clustering in super-resolution localization images of static surfaces in two dimensions. The method also describes how over-counting of labeled molecules contributes to apparent self-clustering and how the effective lateral resolution of an image can be determined. This treatment applies to clustering of proteins and lipids in membranes, where there is significant interest in using super-resolution localization techniques to probe membrane heterogeneity. When images are quantified using pair correlation functions, the magnitude of apparent clustering due to over-counting will vary inversely with the surface density of labeled molecules and does not depend on the number of times an average molecule is counted. Over-counting does not yield apparent co-clustering in double label experiments when pair cross-correlation functions are measured. We apply our analytical method to quantify the distribution of the IgE receptor (Fc{\\epsilon}RI) on the plasma membranes of chemi...

  5. Apparent and Actual Dynamic Contact Angles in Confined Two-Phase Flows

    Science.gov (United States)

    Omori, Takeshi; Kajishima, Takeo

    2016-11-01

    To accurately predict the fluid flow with moving contact lines, it has a crucial importance to use a model for the dynamic contact angle which gives contact angles on the length scale corresponding to the spacial resolution of the fluid solver. The angle which a moving fluid interface forms to a solid surface deviates from an actual (microscopic) dynamic contact angle depending on the distance from the contact line and should be called an apparent (macroscopic) dynamic contact angle. They were, however, often undistinguished especially in the experimental works, on which a number of empirical correlations between a contact angle and a contact line velocity have been proposed. The present study is the first attempt to measure both apparent and actual contact angles from the identical data sets to discuss the difference and the relationship between these two contact angles of difference length scales. The study is conducted by means of numerical simulation, solving the Navier-Stokes equation and the Cahn-Hilliard equation under the generalized Navier boundary condition for the immiscible two-phase flow in channels. The present study also illustrates how the system size and the physical properties of the adjoining fluid affect the apparent and the actual dynamic contact angles. JSPS KAKENHI Grant No. 15K17974.

  6. A novel TDR signal processing technique for measuring apparent dielectric spectrum

    Science.gov (United States)

    Lin, Chih-Ping; Jeh Ngui, Yin; Lin, Chun-Hung

    2017-01-01

    Conventional time-domain reflectometry (TDR) signal interpretation generated single-valued apparent dielectric constant, while sophisticated, inconvenient measurement system and analysis is needed for measuring spectral complex dielectric permittivity (CDP). Niching between these approaches, a novel phase velocity analysis (PVA) method is developed to efficiently measure apparent dielectric spectrum (ADS) directly from TDR signals in a simple, quick, model-free, and inversion-free manner. The proposed PVA method extracts the two reflections from the top and end of the sensing probe by proper window selection and calculates their phase shift at each frequency, from which the phase velocity and corresponding apparent dielectric constant can be determined. Numerical and experimental results demonstrated that PVA is capable of measuring ADS in a frequency band, typically from 100 MHz-1 GHz. The effect of signal truncation was identified as the main cause of poor results outside the effective frequency band. Factors that affect the frequency band of effective ADS were numerically investigated. For highly dispersive materials, the end reflection pulse does not fully develop before the arrival of subsequent multiple reflections, resulting in severe truncation error and decreasing the upper frequency of effective ADS. Methods to estimate and extend the frequency band of effective ADS were further proposed. The simple procedures behind PVA, and its computationally efficient nature, make this method suitable for field monitoring. The resultant ADS is a potential improvement to current applications utilizing a travel time approach.

  7. A new and facile method for measurement of apparent density of monodisperse polymer beads.

    Science.gov (United States)

    Zhang, Qi; Srinivasan, Balasubramanian; Li, Yuanpeng; Jing, Ying; Xing, Chengguo; Chang, Jin; Wang, Jian-Ping

    2010-03-15

    The apparent density, an intrinsic physical property of polymer beads, plays an important role in the application of beads in micro-total analysis systems and separation. Here we have developed a new, facile and milligram-scale method to describe the motion of beads in aqueous solution and further detect the apparent density of beads. The motion of beads in solutions is determined by the viscosity of solutions and the density difference between beads and solutions. In this study, using various glycerol aqueous solutions with certain viscosities and densities, the motion time (i.e. floating or sedimentation time) of hybrid polymer beads was experimentally measured and theoretically deduced, and consequently, the apparent density of monodisperse beads can be quickly and easily calculated. The results indicated that the present method provided a more precise way to predict the movement of hybrid beads in aqueous solution compared with the approach for commercial use. This new method can be potentially employed in flow cytometry, suspension stability, and particle analysis systems.

  8. Genetics of Apparently Sporadic Pheochromocytoma and Paraganglioma in a Chinese Population.

    Science.gov (United States)

    Lee, C H; Cheung, C Y Y; Chow, W S; Woo, Y C; Yeung, C Y; Lang, B H H; Fong, C H Y; Kwok, K H M; Chen, S P L; Mak, C M; Tan, K C B; Lam, K S L

    2015-10-01

    Identification of germline mutation in patients with apparently sporadic pheochromocytomas and paragangliomas is crucial. Clinical indicators, which include young age, bilateral or multifocal, extra-adrenal, malignant, or recurrent tumors, predict the likelihood of harboring germline mutation in Caucasian subjects. However, data on the prevalence of germline mutation, as well as the applicability of these clinical indicators in Chinese, are lacking. We conducted a cross-sectional study at a single endocrine tertiary referral center in Hong Kong. Subjects with pheochromocytomas and paragangliomas were evaluated for the presence of germline mutations involving 10 susceptibility genes, which included NF1, RET, VHL, SDHA, SDHB, SDHC, SDHD, TMEM 127, MAX, and FH genes. Clinical indicators were assessed for their association with the presence of germline mutations. Germline mutations, 2 being novel, were found in 24.4% of the 41 Chinese subjects recruited and 11.4% among those with apparently sporadic presentation. The increasing number of the afore-mentioned clinical indicators significantly correlated with the likelihood of harboring germline mutation in one of the 10 susceptibility genes. (r=0.757, p=0.026). The presence of 2 or more clinical indicators should prompt genetic testing for germline mutations in Chinese subjects. In conclusion, our study confirmed that a significant proportion of Chinese subjects with apparently sporadic pheochromocytoma and paraganglioma harbored germline mutations and these clinical indicators identified from Caucasians series were also applicable in Chinese subjects. This information will be of clinical relevance in the design of appropriate genetic screening strategies in Chinese populations.

  9. Levels of serum immunoglobulins in apparently healthy children and adults in Port Harcourt, Nigeria.

    Science.gov (United States)

    Obiandu, C; Okerengwo, A A; Dapper, D V

    2013-06-30

    Serum levels of the immunoglobulins: IgG, IgA and IgM were determined by the single radial immunodiffusion technique of Mancini in a total of 122 apparently healthy subjects consisting of 43 children (20 males; 23 females) aged 5-12 years and 79 adults (39 males; 40 females) aged 18-65 years resident in Port Harcourt, southeastern Nigeria. The effects of age and sex on the serum levels of the various immunoglobulin types were also determined. The mean values and ranges for the various immunoglobulin types are presented for both children and adults. Although, female children were found to have significantly lower mean values of IgA compared to male children (p0.05). However, female adults had significantly higher mean values of IgG and significantly lower mean values of IgA compared to male adults (pimmunoglobulin between adults and children. The present study reports mean values of the various types of immunoglobulin in apparently healthy children and adults resident in Port Harcourt, southeastern Nigeria. Significant gender differences were observed for some of the immunoglobulin types only amongst adults. Our results suggest that these gender differences amongst adults were apparently a gradual build-up from childhood. The results also confirm suggestions that levels of some immunoglobulin types seen amongst African adults may have possibly been attained during childhood. Our study could be of value since previous reports in this regard have been relatively scanty especially in this part of Nigeria.

  10. Improvement of the Earthquake Early Warning System with Wavefield Extrapolation with Apparent Velocity and Direction

    Science.gov (United States)

    Sato, A.; Yomogida, K.

    2014-12-01

    The early warning system operated by Japan Meteorological Agency (JMA) has been available in public since October 2007.The present system is still not effective in cases, that we cannot assume a nearly circular wavefront expansion from a source. We propose a new approach based on the extrapolation of the early observed wavefield alone without estimating its epicenter. The idea is similar to the migration method in exploration seismology, but we use not only the information of wave field at an early stage (i.e., at time T2 in Figure, but also its normal derivatives the difference between T1 and T2), that is, we utilize the apparent velocity and direction of early-stage wave propagation to predict the wavefield later (at T3 in Fig.). For the extrapolation of wavefield, we need a reliable Green's function from the observed point to a target point at which the wave arrives later. Since the complete 3-D wave propagation is extremely complex, particularly in and around Japan of highly heterogeneous structures, we shall consider a phenomenological 2-D Green's function, that is, a wavefront propagates on the surface with a certain apparent velocity and direction of P wave. This apparent velocity and direction may vary significantly depending on, for example, event depth and an area of propagation, so we examined those of P wave propagating in Japan in various situations. For example, the velocity of shallow events in Hokkaido is 7.1km/s while that in Nagano prefecture is about 5.5km/s. In addition, the apparent velocity depends on event depth, 7.1km/s for the depth of 10km and 8.9km/s for 100km in Hokkaido. We also conducted f-k array analyses of adjacent five or six stations where we can accurately estimate the apparent velocity and direction of P wave. For deep events with relatively simple waveforms, they are easily obtained, but we may need site corrections to enhance correlations of waveforms among stations for shallow ones. In the above extrapolation scheme, we can

  11. A Bayesian Approach for Apparent Inter-plate Coupling in the Central Andes Subduction Zone

    Science.gov (United States)

    Ortega Culaciati, F. H.; Simons, M.; Genrich, J. F.; Galetzka, J.; Comte, D.; Glass, B.; Leiva, C.; Gonzalez, G.; Norabuena, E. O.

    2010-12-01

    We aim to characterize the extent of apparent plate coupling on the subduction zone megathrust with the eventual goal of understanding spatial variations of fault zone rheology, inferring relationships between apparent coupling and the rupture zone of big earthquakes, as well as the implications for earthquake and tsunami hazard. Unlike previous studies, we approach the problem from a Bayesian perspective, allowing us to completely characterize the model parameter space by searching a posteriori estimates of the range of allowable models instead of seeking a single optimum model. Two important features of the Bayesian approach are the possibility to easily implement any kind of physically plausible a priori information and to perform the inversion without regularization, other than that imposed by the way in which we parameterize the forward model. Adopting a simple kinematic back-slip model and a 3D geometry of the inter-plate contact zone, we can estimate the probability of apparent coupling (Pc) along the plate interface that is consistent with a priori information (e.g., approximate rake of back-slip) and available geodetic measurements. More generally, the Bayesian approach adopted here is applicable to any region and eventually would allow one to evaluate the spatial relationship between various inferred distributions of fault behavior (e.g., seismic rupture, postseismic creep, and apparent interseismic coupling) in a quantifiable manner. We apply this methodology to evaluate the state of apparent inter-seismic coupling in the Chilean-Peruvian subduction margin (12 S - 25 S). As observational constraints, we use previously published horizontal velocities from campaign GPS [Kendrick et al., 2001, 2006] as well as 3 component velocities from a recently established continuous GPS network in the region (CAnTO). We compare results from both joint and independent use of these data sets. We obtain patch like features for Pc with higher values located above 60 km

  12. Bronchoscopic lung volume reduction

    Directory of Open Access Journals (Sweden)

    M. I. Polkey

    2006-12-01

    Full Text Available Surgical lung volume reduction can improve exercise performance and forced expiratory volume in one second in patients with emphysema. However, the procedure is associated with a 5% mortality rate and a nonresponse rate of 25%. Accordingly, interest has focused on alternative ways of reducing lung volume. Two principle approaches are used: collapse of the diseased area using blockers placed endobronchially and the creation of extrapulmonary pathways. Preliminary data from the former approach suggest that it can be successful and that the magnitude of success is related to reduction in dynamic hyperinflation.

  13. Unsteady flow volumes

    Energy Technology Data Exchange (ETDEWEB)

    Becker, B.G.; Lane, D.A.; Max, N.L.

    1995-03-01

    Flow volumes are extended for use in unsteady (time-dependent) flows. The resulting unsteady flow volumes are the 3 dimensional analog of streamlines. There are few examples where methods other than particle tracing have been used to visualize time varying flows. Since particle paths can become convoluted in time there are additional considerations to be made when extending any visualization technique to unsteady flows. We will present some solutions to the problems which occur in subdivision, rendering, and system design. We will apply the unsteady flow volumes to a variety of field types including moving multi-zoned curvilinear grids.

  14. Volume regulation in epithelia

    DEFF Research Database (Denmark)

    Larsen, Erik Hviid; Hoffmann, Else Kay

    2016-01-01

    function of iso-osmotic fluid transport that depends on Na+ recirculation. The causative relationship is discussed for a fluid-absorbing and a fluid-secreting epithelium of which the Na+ recirculation mechanisms have been identified. A large number of transporters and ion channels involved in cell volume...... regulation are cloned. The volume-regulated anion channel (VRAC) exhibiting specific electrophysiological characteristics seems exclusive to serve cell volume regulation. This is contrary to K+ channels as well as cotransporters and exchange mechanisms that may serve both transepithelial transport and cell...

  15. Towards the Amplituhedron Volume

    CERN Document Server

    Ferro, Livia; Orta, Andrea; Parisi, Matteo

    2015-01-01

    It has been recently conjectured that scattering amplitudes in planar N=4 super Yang-Mills are given by the volume of the (dual) amplituhedron. In this paper we show some interesting connections between the tree-level amplituhedron and a special class of differential equations. In particular we demonstrate how the amplituhedron volume for NMHV amplitudes is determined by these differential equations. The new formulation allows for a straightforward geometric description, without any reference to triangulations. Finally we discuss possible implications for volumes related to generic N^kMHV amplitudes.

  16. Environmental chemistry: Volume A

    Energy Technology Data Exchange (ETDEWEB)

    Yen, T.F.

    1999-08-01

    This is an extensive introduction to environmental chemistry for engineering and chemical professionals. The contents of Volume A include a brief review of basic chemistry prior to coverage of litho, atmo, hydro, pedo, and biospheres.

  17. Renormalized Volumes with Boundary

    CERN Document Server

    Gover, A Rod

    2016-01-01

    We develop a general regulated volume expansion for the volume of a manifold with boundary whose measure is suitably singular along a separating hypersurface. The expansion is shown to have a regulator independent anomaly term and a renormalized volume term given by the primitive of an associated anomaly operator. These results apply to a wide range of structures. We detail applications in the setting of measures derived from a conformally singular metric. In particular, we show that the anomaly generates invariant (Q-curvature, transgression)-type pairs for hypersurfaces with boundary. For the special case of anomalies coming from the volume enclosed by a minimal hypersurface ending on the boundary of a Poincare--Einstein structure, this result recovers Branson's Q-curvature and corresponding transgression. When the singular metric solves a boundary version of the constant scalar curvature Yamabe problem, the anomaly gives generalized Willmore energy functionals for hypersurfaces with boundary. Our approach ...

  18. Free volume under shear

    Science.gov (United States)

    Maiti, Moumita; Vinutha, H. A.; Sastry, Srikanth; Heussinger, Claus

    2015-10-01

    Using an athermal quasistatic simulation protocol, we study the distribution of free volumes in sheared hard-particle packings close to, but below, the random-close packing threshold. We show that under shear, and independent of volume fraction, the free volumes develop features similar to close-packed systems — particles self-organize in a manner as to mimick the isotropically jammed state. We compare athermally sheared packings with thermalized packings and show that thermalization leads to an erasure of these structural features. The temporal evolution in particular the opening-up and the closing of free-volume patches is associated with the single-particle dynamics, showing a crossover from ballistic to diffusive behavior.

  19. Integers annual volume 2013

    CERN Document Server

    Landman, Bruce

    2014-01-01

    ""Integers"" is a refereed online journal devoted to research in the area of combinatorial number theory. It publishes original research articles in combinatorics and number theory. This work presents all papers of the 2013 volume in book form.

  20. Generalized Partial Volume

    DEFF Research Database (Denmark)

    Darkner, Sune; Sporring, Jon

    2011-01-01

    Mutual Information (MI) and normalized mutual information (NMI) are popular choices as similarity measure for multimodal image registration. Presently, one of two approaches is often used for estimating these measures: The Parzen Window (PW) and the Generalized Partial Volume (GPV). Their theoret......Mutual Information (MI) and normalized mutual information (NMI) are popular choices as similarity measure for multimodal image registration. Presently, one of two approaches is often used for estimating these measures: The Parzen Window (PW) and the Generalized Partial Volume (GPV...

  1. Reachable volume RRT

    KAUST Repository

    McMahon, Troy

    2015-05-01

    © 2015 IEEE. Reachable volumes are a new technique that allows one to efficiently restrict sampling to feasible/reachable regions of the planning space even for high degree of freedom and highly constrained problems. However, they have so far only been applied to graph-based sampling-based planners. In this paper we develop the methodology to apply reachable volumes to tree-based planners such as Rapidly-Exploring Random Trees (RRTs). In particular, we propose a reachable volume RRT called RVRRT that can solve high degree of freedom problems and problems with constraints. To do so, we develop a reachable volume stepping function, a reachable volume expand function, and a distance metric based on these operations. We also present a reachable volume local planner to ensure that local paths satisfy constraints for methods such as PRMs. We show experimentally that RVRRTs can solve constrained problems with as many as 64 degrees of freedom and unconstrained problems with as many as 134 degrees of freedom. RVRRTs can solve problems more efficiently than existing methods, requiring fewer nodes and collision detection calls. We also show that it is capable of solving difficult problems that existing methods cannot.

  2. The origin of a large apparent tortuosity factor for the Knudsen diffusion inside monoliths of a samaria-alumina aerogel catalyst: a diffusion NMR study.

    Science.gov (United States)

    Mueller, R; Zhang, S; Klink, M; Bäumer, M; Vasenkov, S

    2015-11-01

    Pulsed field gradient (PFG) NMR was applied to measure tortuosity factors for carbon dioxide diffusion in the Knudsen and gas regimes inside monoliths of a samaria-alumina aerogel catalyst, a high porosity material containing micropores in addition to meso- and macropores. The apparent tortuosity factor obtained from PFG NMR measurements for the Knudsen diffusion in the meso- and macropores of the catalyst has an unexpectedly large value of approximately 6 if carbon dioxide adsorption in the micropores and other types of surface adsorption sites of the catalyst is ignored. At the same time, the corresponding apparent tortuosity factor in the gas regime was found to be around 2. Application of a proposed model which describes fast molecular exchange between the surface adsorption sites and the main pore volume of the catalyst yields corrected tortuosity factors which depend only on the pore system geometry. Using this model, the corrected tortuosity factors were found to be around 2 for both diffusion regimes, in agreement with the expectations based on a high porosity of the studied catalyst.

  3. Decline of Pulmonary Function Is Associated With the Presence of Rheumatoid Factor in Korean Health Screening Subjects Without Clinically Apparent Lung Disease: A Cross-Sectional Study.

    Science.gov (United States)

    Hwang, Jiwon; Song, Jae-Uk; Ahn, Joong Kyong

    2016-05-01

    Although higher-than-normal levels of rheumatoid factor (RF) are often observed in subjects without specific medical problems, little is known about the influence of RF on pulmonary function in health screening subjects. This study aimed to determine the association between the presence of RF and decreased pulmonary function in Korean health screening subjects without any history of joint disease or clinically apparent lung disease.A total of 115,641 study subjects (age range, 18-88 years) participated in the health checkup program. We excluded subjects who did not have pulmonary function test, as well as those with abnormal chest radiographs. Subjects with medical history of arthritis including rheumatoid arthritis, and lung disease based on the self-reported questionnaire. Final analysis was performed on 94,438 Koreans (41,261 women).RF-positive subjects had a lower forced vital capacity (FVC) predicted value and forced expiratory volume in 1 s (FEV1) predicted value than RF-negative subjects (82.8 ± 11.5% vs 83.8 ± 11.4% for FVC% predicted and 83.5 ± 13.0% vs 85.1 ± 12.9% for FEV1% predicted, P pulmonary function in apparently healthy subjects. A follow-up study to investigate serial changes in pulmonary function may reveal the actual influence of raised RF titers.

  4. Increasing nitrogen rates in rice and its effect on plant nutrient composition and nitrogen apparent recovery

    Directory of Open Access Journals (Sweden)

    Juan Hirzel

    2013-12-01

    Full Text Available Rice (Oryza sativa L. is one of the essential foods of the human diet; advances in agronomic crop management can improve productivity and profitability as well as reduce adverse environmental impacts. Nitrogen rates in Chile are generally based on crop yield without considering other agronomic factors. The objective of this experiment was to determine the effect of increasing N rates on plant nutrient composition and N apparent recovery in rice cultivated in five different locations in Chile. The five sites located in central Chile belong to one of the following soil orders: Inceptisol, Alfisol, and Vertisol; they were cropped in field conditions with 'Zafiro-INIA' rice fertilized with 0, 80, and 160 kg N ha-1. Whole-plant total DM, macronutrient composition, and N apparent recovery efficiency (NARE were determined at grain harvest. Results indicate that all evaluated parameters, with the exception of K concentration, were affected by the soil used. Nitrogen rates only affected total DM production and P, K, and Mg concentrations in plants. Phosphorus and K response decreased when N was added to some soils, which is associated with its chemical properties. Magnesium concentration exhibited an erratic effect, but it was not affected by the N rate in most soils. Nitrogen apparent recovery efficiency was not affected by the N rate and accounted for approximately 49% and 41% for 80 and 160 kg N ha-1, respectively. Macronutrient composition was 5.1-7.7 g N, 1.3-1.8 g P, 5.4-10.8 g K, 1.68-2.57 g Ca, and 0.81-1.45 g Mg kg-1 of total DM.

  5. Temperature and depth mediate resource competition and apparent competition between Mysis diluviana and kokanee.

    Science.gov (United States)

    Schoen, Erik R; Beauchamp, David A; Buettner, Anna R; Overman, Nathanael C

    2015-10-01

    In many food webs, species in similar trophic positions can interact either by competing for resources or boosting shared predators (apparent competition), but little is known about how the relative strengths of these interactions vary across environmental gradients. Introduced Mysis diluviana shrimp interact with planktivorous fishes such as kokanee salmon (lacustrine Oncorhynchus nerka) through both of these pathways, and effective management depends on understanding which interaction is more limiting under different conditions. An "environmental matching" hypothesis predicts the ecological impacts of Mysis are maximized under cool conditions near its thermal optimum. In addition, we hypothesized Mysis is more vulnerable to predation by lake trout in relatively shallow waters, and therefore Mysis enhances lake trout density and limits kokanee through apparent competition more strongly in shallower habitats. We tested whether these hypotheses could explain food web differences between two connected lake basins, one relatively shallow and the other extremely deep. The shallower basin warmed faster, thermally excluded Mysis from surface waters for 75% longer, and supported 2.5-18 times greater seasonal production of cladoceran zooplankton than the deeper basin, standardized by surface area. Mysis consumed 14-22% less zooplankton in the shallower basin, and lower ratios of total planktivore consumption to zooplankton production (C:P) indicated less potential for resource competition with kokanee, consistent with environmental matching. Lake trout diets contained more Mysis in the shallower basin and at shallower sampling sites within both basins. The catch rate of lake trout was seven times greater and the predation risk for kokanee was 4-5 times greater in the shallower basin than in the deeper basin, consistent with stronger apparent competition in shallower habitats. Understanding how the strengths of these interactions are mediated by temperature and depth would

  6. Effects of apparent temperature on daily mortality in Lisbon and Oporto, Portugal

    Directory of Open Access Journals (Sweden)

    Casimiro Elsa

    2010-03-01

    Full Text Available Abstract Background Evidence that elevated temperatures can lead to increased mortality is well documented, with population vulnerability being location specific. However, very few studies have been conducted that assess the effects of temperature on daily mortality in urban areas in Portugal. Methods In this paper time-series analysis was used to model the relationship between mean apparent temperature and daily mortality during the warm season (April to September in the two largest urban areas in Portugal: Lisbon and Oporto. We used generalized additive Poisson regression models, adjusted for day of week and season. Results Our results show that in Lisbon, a 1°C increase in mean apparent temperature is associated with a 2.1% (95%CI: 1.6, 2.5, 2.4% (95%CI: 1.7, 3.1 and 1.7% (95%CI: 0.1, 3.4 increase in all-causes, cardiovascular, and respiratory mortality, respectively. In Oporto the increase was 1.5% (95%CI: 1.0, 1.9, 2.1% (95%CI: 1.3, 2.9 and 2.7% (95%CI: 1.2, 4.3 respectively. In both cities, this increase was greater for the group >65 years. Conclusion Even without extremes in apparent temperature, we observed an association between temperature and daily mortality in Portugal. Additional research is needed to allow for better assessment of vulnerability within populations in Portugal in order to develop more effective heat-related morbidity and mortality public health programs.

  7. Lubricin deficiency in the murine lumbar intervertebral disc results in elevated torsional apparent modulus.

    Science.gov (United States)

    Teeple, Erin; Aslani, Koosha; Shalvoy, Matthew R; Medrano, Jade E; Zhang, Ling; Machan, Jason T; Fleming, Braden C; Jay, Gregory D

    2015-07-16

    The purpose of this study was to investigate the mechanical consequences of proteoglycan 4 (Prg4) deficiency on intervertebral disc mechanics using a Prg4 knockout mouse model. Prg4, also called lubricin, was first identified as the boundary lubricant in synovial fluid but has subsequently been localized within a number of musculoskeletal tissues in areas subjected to shear and tensile stresses, including the intervertebral disc. The function of lubricin in the intervertebral disc has not been determined. Lumbar level 1-2 vertebral body-disc-vertebral body motion segments were isolated from Prg4 null mice and wild type (WT) litter mate controls. Disc dimensions were measured and motion segments were tested in axial loading and torsion. Torque measurements and disc dimensions were used to calculate the torsional apparent modulus for discs from Prg4 null and WT discs. Discs from Prg4 null mice had a significantly smaller mean transverse disc area (p=0.0057), with a significantly larger proportion of this area occupied by the nucleus pulposus (p<0.0001), compared to WT specimens. Apparent torsional moduli were found to be elevated in Prg4 null lumbar discs compared to WT controls at 10-10° (p=0.0048) and 10-30° (p=0.0127) rotation. This study suggests a functional role for Prg4 in the murine intervertebral disc. The absence of Prg4 was associated with an increased apparent torsional modulus and the structural consequences of Prg4 deficiency in the intervertebral disc, with expansion of the area of the nucleus pulposus relative to the transverse disc area in Prg4 null specimens.

  8. Application of the extreme value approaches to the apparent magnitude distribution of the earthquakes

    Science.gov (United States)

    Tinti, S.; Mulargia, F.

    1985-03-01

    The apparent magnitude of an earthquake y is defined as the observed magnitude value and differs from the true magnitude m because of the experimental noise n. If f(m) is the density distribution of the magnitude m, and if g(n) is the density distribution of the error n, then the density distribution of y is simply computed by convolving f and g, i.e. h(y)=f*g. If the distinction between y and m is not realized, any statistical analysis based on the frequency-magnitude relation of the earthquake is bound to produce questionable results. In this paper we investigate the impact of the apparent magnitude idea on the statistical methods that study the earthquake distribution by taking into account only the largest (or extremal) earthquakes. We use two approaches: the Gumbel method based on Gumbel theory ( Gumbel, 1958), and the Poisson method introduced by Epstein and Lomnitz (1966). Both methods are concerned with the asymptotic properties of the magnitude distributions. Therefore, we study and compare the asymptotic behaviour of the distributions h(y) and f(m) under suitable hypotheses on the nature of the experimental noise. We investigate in detail two dinstinct cases: first, the two-side limited symmetrical noise, i.e. the noise that is bound to assume values inside a limited region, and second, the normal noise, i.e. the noise that is distributed according to a normal symmetric distribution. We further show that disregarding the noise generally leads to biased results and that, in the framework of the apparent magnitude, the Poisson approach preserves its usefulness, while the Gumbel method gives rise to a curious paradox.

  9. Dynamic aspects of apparent attenuation and wave localization in layered media

    Science.gov (United States)

    Haney, M.M.; Van Wijk, K.

    2008-01-01

    We present a theory for multiply-scattered waves in layered media which takes into account wave interference. The inclusion of interference in the theory leads to a new description of the phenomenon of wave localization and its impact on the apparent attenuation of seismic waves. We use the theory to estimate the localization length at a CO2 sequestration site in New Mexico at sonic frequencies (2 kHz) by performing numerical simulations with a model taken from well logs. Near this frequency, we find a localization length of roughly 180 m, leading to a localization-induced quality factor Q of 360.

  10. Eye torsion and the apparent horizon under head tilt and visual field rotation

    Science.gov (United States)

    Merker, B. H.; Held, R.

    1981-01-01

    Two different experimental manipulations, namely head tilt and the viewing of a visual display rotating around the line of sight, induce torsional displacements of the eyes and a tilting of the apparent horizon. The present study examines the routes by which visual (field rotation) and otolith-proprioceptive (head tilt) sources of afference influence horizon judgments. In particular, the relationship between torsional eye movements and horizon estimates is addressed. The results indicate that visual and otolith-proprioceptive information sum directly in their influence on eye torsion, but interact more complexly in horizon estimates, indicating a dissociation of their central determinants.

  11. High bone mineral apparent density in children with X-linked hypophosphatemia

    DEFF Research Database (Denmark)

    Beck-Nielsen, Signe; Brixen, K; Gram, J

    2013-01-01

    Bone mineral apparent density (BMAD) in children with X-linked hypophosphatemia (XLH) was evaluated, as they are unlikely to have extra-skeletal ossifications contributing to the elevated bone mineral density of the spine in adult patients. Children with XLH also had significantly higher BMAD...... of the spine compared to femoral neck. INTRODUCTION: BMAD obtained by dual-energy X-ray absorptiometry scans in children with XLH was evaluated, as they are unlikely to have the extra-skeletal ossifications contributing to the elevated bone mineral density of the spine in adult patients. METHODS: A total of 15...

  12. Apparent Cooling Rate of 7°C per Hour in an Avalanche Victim.

    Science.gov (United States)

    Ströhle, Mathias; Putzer, Gabriel; Procter, Emily; Paal, Peter

    2015-12-01

    Avalanche victims can become hypothermic within 35 minutes of snow burial. However, reported cooling rates for avalanche victims are highly variable and it is poorly understood how much cooling is influenced by general factors (body composition, clothing, ambient conditions, duration of burial, and metabolism), unknown inter-individual factors or other phenomena (e.g., afterdrop). We report an apparent cooling rate of ∼7°C in ∼60 minutes in a healthy backcountry skier who was rewarmed with forced air and warm fluids and was discharged after 2 weeks without neurological sequelae.

  13. Ventricular Arrhythmias in Apparently Normal Hearts: Who Needs an Implantable Cardiac Defibrillator?

    Science.gov (United States)

    Tan, Alex Y; Ellenbogen, Kenneth

    2016-09-01

    Idiopathic ventricular tachycardia is often considered a benign form of ventricular arrhythmia in patients without apparent structural heart disease. However, a subset of patients may develop malignant ventricular arrhythmias and present with syncope and sudden cardiac arrest. Survivors of cardiac arrest are candidates for implantable cardiac defibrillators (ICDs). The indications for ICDs in patients with less than a full-blown cardiac arrest presentation but with electrocardiographically high-risk ectopy features remain uncertain. This article addresses some of the uncertainties and pitfalls in ICD risk stratification in this patient group and explores potential mechanisms for malignant conversion of benign premature ventricular complexes to sustained arrhythmia.

  14. Correlation functions quantify super-resolution images and estimate apparent clustering due to over-counting.

    Directory of Open Access Journals (Sweden)

    Sarah L Veatch

    Full Text Available We present an analytical method using correlation functions to quantify clustering in super-resolution fluorescence localization images and electron microscopy images of static surfaces in two dimensions. We use this method to quantify how over-counting of labeled molecules contributes to apparent self-clustering and to calculate the effective lateral resolution of an image. This treatment applies to distributions of proteins and lipids in cell membranes, where there is significant interest in using electron microscopy and super-resolution fluorescence localization techniques to probe membrane heterogeneity. When images are quantified using pair auto-correlation functions, the magnitude of apparent clustering arising from over-counting varies inversely with the surface density of labeled molecules and does not depend on the number of times an average molecule is counted. In contrast, we demonstrate that over-counting does not give rise to apparent co-clustering in double label experiments when pair cross-correlation functions are measured. We apply our analytical method to quantify the distribution of the IgE receptor (FcεRI on the plasma membranes of chemically fixed RBL-2H3 mast cells from images acquired using stochastic optical reconstruction microscopy (STORM/dSTORM and scanning electron microscopy (SEM. We find that apparent clustering of FcεRI-bound IgE is dominated by over-counting labels on individual complexes when IgE is directly conjugated to organic fluorophores. We verify this observation by measuring pair cross-correlation functions between two distinguishably labeled pools of IgE-FcεRI on the cell surface using both imaging methods. After correcting for over-counting, we observe weak but significant self-clustering of IgE-FcεRI in fluorescence localization measurements, and no residual self-clustering as detected with SEM. We also apply this method to quantify IgE-FcεRI redistribution after deliberate clustering by

  15. Apparent Clustering of Intermediate-redshift Galaxies as a Probe of Dark Energy

    CERN Document Server

    Matsubara, T; Matsubara, Takahiko; Szalay, Alexander S.

    2002-01-01

    We show the apparent redshift-space clustering of galaxies in redshift range of 0.2-0.4 provides surprisingly useful constraints on dark energy component in the universe, because of the right balance between the density of objects and the survey depth. We apply Fisher matrix analyses to the the Luminous Red Galaxies (LRGs) in the Sloan Digital Sky Survey (SDSS), as a concrete example. Possible degeneracies in the evolution of the equation of state (EOS) and the other cosmological parameters are clarified.

  16. [How I EXPLORE ... AN APPARENT LIFE THREATENING EVENT OF THE INFANT].

    Science.gov (United States)

    Zambelli, L; Battisti, O

    2016-04-01

    The ALTE (Apparent Life Threatening Event) of the infant is a frequent presenting complaint. The clinical presentation is varied, ranging from an innocuous event (as a change in skin color) to something as tragic as a sudden infant death. In all circumstances, it is always a very worrying event for the parents and the family circle. Many etiologies can explain the ALTE, and their investigation can be complicated. In this paper, the etiologies and diagnostic tests will be briefly introduced, with a reminder of the sudden infant death syndrome.

  17. Biosynthesis of Xanthan Gum from Fermenting Shrimp Shell: Yield and Apparent Viscosity

    OpenAIRE

    2014-01-01

    With the aim of producing xanthan gum, the effects of an aqueous shrimp shell extract (SSAE) as the source of carbon and nitrogen on the yield and apparent viscosity of the gums produced by fermentation using three native strains of Xanthomonas campestris were studied. It was found that the SSAE contained 89.75% moisture, 0.054% ash, 8.069% protein, 0.787 lipids, and 1.337% carbohydrates. Media containing different concentrations of SSAE and supplemented with urea (0.01%) and phosphate (0.1%)...

  18. Solution properties and taste behavior of lactose monohydrate in aqueous ascorbic acid solutions at different temperatures: Volumetric and rheological approach.

    Science.gov (United States)

    Sarkar, Abhijit; Sinha, Biswajit

    2016-11-15

    The densities and viscosities of lactose monohydrate in aqueous ascorbic acid solutions with several molal concentrations m=(0.00-0.08)molkg(-1) of ascorbic acid were determined at T=(298.15-318.15)K and pressure p=101kPa. Using experimental data apparent molar volume (ϕV), standard partial molar volume (ϕV(0)), the slope (SV(∗)), apparent specific volumes (ϕVsp), standard isobaric partial molar expansibility (ϕE(0)) and its temperature dependence [Formula: see text] the viscosity B-coefficient and solvation number (Sn) were determined. Viscosity B-coefficients were further employed to obtain the free energies of activation of viscous flow per mole of the solvents (Δμ1(0≠)) and of the solute (Δμ2(0≠)). Effects of molality, solute structure and temperature and taste behavior were analyzed in terms of solute-solute and solute-solvent interactions; results revealed that the solutions are characterized predominantly by solute-solvent interactions and lactose monohydrate behaves as a long-range structure maker.

  19. Apparent digestibility of nutrients, energy, and amino acid of nontoxic and detoxified physic nut cakes for Nile tilapia

    Directory of Open Access Journals (Sweden)

    Hamilton Hisano

    2015-09-01

    Full Text Available Abstract:The objective of this work was to evaluate the apparent digestibility coefficients of nutrients, energy, and amino acids of nontoxic and detoxified physic nut cakes treated with solvent plus posterior extrusion, for Nile tilapia. The apparent digestibility coefficients of crude protein and gross energy were higher for detoxified than for nontoxic physic nut cake. However, the apparent digestibility coefficient of ether extract of the nontoxic physic nut cake was higher than that of the detoxified one. The apparent digestibility coefficient of amino acids of both feed ingredients was superior to 80%, except for glycine, for the nontoxic psychic nut cake, and for threonine, for the detoxified one. Nontoxic and detoxified physic nut cakes show apparent digestibility coefficient values equivalent to those of the other evaluated oilseeds and potential for inclusion in Nile tilapia diets.

  20. Hepatitis B virus (HBV) and dual HBV-hepatitis delta virus (HDV) infection in apparently healthy persons.

    Science.gov (United States)

    Brehar-Cioflec, D; Claici, C; Roşiu, N; Negrea, D A; Moldovan, R; Coşniţă, M

    1998-01-01

    The main aims of the present study were to evaluate the transfusional risk concerning HBV and HBV-HDV infections and the prevalence of viral serum markers in apparently healthy persons. Our study included 226 apparently healthy persons in whom we performed tests for HBV (HBsAg, HBsAb, HBcAb) and HDV (Delta Ab) serum markers, using the enzyme immunoassay. In 45 (19.9%) subjects we detected serum HBsAg. In the 181 HBsAg-negative apparently healthy persons, our tests detected HBsAb (31 subjects) and HBcAb (49 subjects). Thus, 125 (55.3%) of the 226 apparently healthy persons had serologic evidence of past HBV infections. Delta Ab were detected in 3 (1.3%) of our subjects. We must state that one of the three Delta Ab-positive apparently healthy persons tested negative for both HBsAg and HBcAb.

  1. Can self-representationalism explain away the apparent irreducibility of consciousness?

    Science.gov (United States)

    McClelland, Tom

    Kriegel's self-representationalist (SR) theory of phenomenal consciousness pursues two projects. The first is to offer a positive account of how conscious experience arises from physical brain processes. The second is to explain why consciousness misleadingly appears to be irreducible to the physical i.e. to 'demystify' consciousness. This paper seeks to determine whether SR succeeds on the second project. Kriegel trades on a distinction between the subjective character and qualitative character of conscious states. Subjective character is the property of being a conscious state at all, while qualitative character determines what it is like to be in that state. Kriegel claims that SR explains why subjective character misleadingly appears irreducible, thereby neutralising the apparent irreducibility of consciousness. I argue that although SR credibly demystifies subjective character, it cannot explain why qualitative character also appears irreducible. I conclude that we should pursue the possibility of a hybrid position that combines SR with an account that does explain the apparent irreducibility of qualitative character.

  2. Assessment of the apparent activation energies for gas/solid reactions-carbonate decomposition

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The guidelines for assessing the apparent activation energies of gas/solid reactions have been proposed based on the ex-perimental results from literatures. In CO2 free inlet gas flow, CaCO3 decomposition between 950 and 1250 K with thin sample layercould be controlled by the interfacial chemical reaction with apparent activation energy E = (215+10) kJ/mol and E = (200±10)kJ/mol at T = 813 to 1020 K, respectively. With relatively thick sample layer between 793 and 1273 K, the CaCO3 decompositioncould be controlled by one or more steps involving self-cooling, nucleation, intrinsic diffusion and heat transfer of gases, and E couldvary between 147 andl90 kJ/mol. In CO2 containing inlet gas flow (5%-100% of CO2), E was determined to be varied from 949 to2897 kJ/mol. For SrCO3 and BaCO3 decompositions controlled by the interfacial chemical reaction, E was (213+15) kJ/mol (1000-1350 K) and (305+15) kJ/mol (1260-1400 K), respectively.

  3. Cardiopulmonary resuscitation of apparently stillborn infants: survival and long-term outcome.

    Science.gov (United States)

    Jain, L; Ferre, C; Vidyasagar, D; Nath, S; Sheftel, D

    1991-05-01

    To determine the outcome of apparently stillborn infants who received cardiopulmonary resuscitation, we studied the short- and long-term outcome of 93 infants who had an Apgar score of 0 at 1 minute of age and were resuscitated at birth. Sixty-two (66.6%) responded and left the delivery room alive; 26 (42%) of the 62 infants died in the neonatal period and 36 infants were discharged home; of the 36 infants, three subsequently died during infancy. Of the 33 survivors, ten were lost to follow-up after discharge. Developmental assessment of 23 of 33 long-term survivors revealed normal outcome in 14 (61.7%), abnormal results in 6 (26%), and suspect status in 3 (13%). Fifty-eight infants had an Apgar score of 0 at greater than or equal to 10 minutes of age and all except one died; the surviving infant has an abnormal developmental outcome. We conclude that 39% of apparently stillborn infants who were resuscitated survived beyond the neonatal period and that 61% of the 23 survivors who were available for developmental follow-up had normal development at the time of last examination. Survival was unlikely if there was no response after 10 minutes of resuscitation.

  4. Apparent diffusion coefficient parametric response mapping MRI for follow-up of glioblastoma

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Ra Gyoung [Catholic Kwandong University International St. Mary' s Hospital, Catholic Kwandong University College of Medicine, Department of Radiology, Seo-gu, Incheon (Korea, Republic of); Kim, Ho Sung; Hong, Gil Sun; Kim, Sang Joon [Asan Medical Center, University of Ulsan College of Medicine, Department of Radiology and Research Institute of Radiology, Songpa-Gu, Seoul (Korea, Republic of); Kim, Dae Yoon [Bundang Jesaeng Hospital, Department of Radiology, Seongnam-si, Gyeonggi-do (Korea, Republic of)

    2016-04-15

    To determine the diagnostic superiority of parametric response mapping of apparent diffusion coefficient (ADCPR) for predicting glioblastoma treatment response, compared to single time point measurement. Fifty post-treatment glioblastoma patients were enrolled. ADCPR was calculated from serial apparent diffusion coefficient (ADC) maps acquired before and at the time of first detection of an enlarged contrast-enhancing lesion on voxel-by-voxel basis. The percentage-decrease in ADCPR and tenth percentile histogram cutoff value of ADC (ADC10) were compared at subsequent 3-month and 1-year follow-ups. The percentage-decrease in ADCPR was significantly higher in the progression group (mean = 33.2-38.3 %) than in the stable-response group (mean = 9.7 %) at 3 months follow-up (corrected p < 0.001 for both readers). ADCPR significantly improved area under the receiver operating characteristic curve from 0.67 to 0.88 (corrected p = 0.037) and from 0.70 to 0.92 (corrected p = 0.020) for both readers, respectively, compared to ADC10 at 3-month follow-up, but did not significantly improve at 1-year follow-up. The inter-reader agreement was higher for ADCPR than ADC10 (intraclass correlation coefficient, 0.93 versus 0.86). Voxel-based ADCPR appears to be a superior imaging biomarker than ADC, particularly for predicting early tumour progression in patients with glioblastoma. (orig.)

  5. Brain herniation in a patient with apparently normal intracranial pressure: a case report

    Directory of Open Access Journals (Sweden)

    Dahlqvist Mats B

    2010-08-01

    Full Text Available Abstract Introduction Intracranial pressure monitoring is commonly implemented in patients with neurologic injury and at high risk of developing intracranial hypertension, to detect changes in intracranial pressure in a timely manner. This enables early and potentially life-saving treatment of intracranial hypertension. Case presentation An intraparenchymal pressure probe was placed in the hemisphere contralateral to a large basal ganglia hemorrhage in a 75-year-old Caucasian man who was mechanically ventilated and sedated because of depressed consciousness. Intracranial pressures were continuously recorded and never exceeded 17 mmHg. After sedation had been stopped, our patient showed clinical signs of transtentorial brain herniation, despite apparently normal intracranial pressures (less than 10 mmHg. Computed tomography revealed that the size of the intracerebral hematoma had increased together with significant unilateral brain edema and transtentorial herniation. The contralateral hemisphere where the intraparenchymal pressure probe was placed appeared normal. Our patient underwent emergency decompressive craniotomy and was tracheotomized early, but did not completely recover. Conclusions Intraparenchymal pressure probes placed in the hemisphere contralateral to an intracerebral hematoma may dramatically underestimate intracranial pressure despite apparently normal values, even in the case of transtentorial brain herniation.

  6. New Late Permian paleomagnetic data from Argentina: Refinement of the apparent polar wander path of Gondwana

    Science.gov (United States)

    Domeier, Mathew; van der Voo, Rob; Tohver, Eric; Tomezzoli, Renata N.; Vizan, Haroldo; Torsvik, Trond H.; Kirshner, Jordan

    2011-07-01

    The Late Paleozoic-Early Mesozoic apparent polar wander path of Gondwana is largely constructed from relatively old paleomagnetic results, many of which are considered unreliable by modern standards. Paleomagnetic results derived from sedimentary sequences, which are generally poorly dated and prone to inclination shallowing, are especially common. Here we report the results of a joint paleomagnetic-geochronologic study of a volcanic complex in central Argentina. U-Pb dating of zircons has yielded a robust age estimate of 263.0 +1.6/-2.0 Ma for the complex. Paleomagnetic analysis has revealed a pretilting (primary Permian) magnetization with dual polarities. Rock magnetic experiments have identified pseudo-single domain (titano)magnetite and hematite as the mineralogic carriers of the magnetization. Lightning-induced isothermal remagnetizations are widespread in the low-coercivity magnetic carriers. The resulting paleomagnetic pole is 80.1°S, 349.0°E, A95 = 3.3°, N = 35, and it improves a Late Permian mean pole calculated from a filtered South American paleomagnetic data set. More broadly, this new, high-quality, igneous-based paleomagnetic pole falls between the previously distinct Late Permian segments of the Laurussian and Gondwanan apparent polar wander paths, suggesting that the long-recognized disparity between these large paleomagnetic data sets may be primarily due to the inclusion of low-quality or systemically biased data.

  7. Bisphosphonate treatment affects trabecular bone apparent modulus through micro-architecture rather than matrix properties.

    Science.gov (United States)

    Day, J S; Ding, M; Bednarz, P; van der Linden, J C; Mashiba, T; Hirano, T; Johnston, C C; Burr, D B; Hvid, I; Sumner, D R; Weinans, H

    2004-05-01

    Bisphosphonates are emerging as an important treatment for osteoporosis. But whether the reduced fracture risk associated with bisphosphonate treatment is due to increased bone mass, improved trabecular architecture and/or increased secondary mineralization of the calcified matrix remains unclear. We examined the effects of bisphosphonates on both the trabecular architecture and matrix properties of canine trabecular bone. Thirty-six beagles were divided into a control group and two treatment groups, one receiving risedronate and the other alendronate at 5-6 times the clinical dose for osteoporosis treatment. After one year, the dogs were killed, and samples from the first lumbar vertebrae were examined using a combination of micro-computed tomography, finite element modeling, and mechanical testing. By combining these methods, we examined the treatment effects on the calcified matrix and trabecular architecture independently. Conventional histomorphometry and microdamage data were obtained from the second and third lumbar vertebrae of the same dogs [Bone 28 (2001) 524]. Bisphosphonate treatment resulted in an increased apparent Young's modulus, decreased bone turnover, increased calcified matrix density, and increased microdamage. We could not detect any change in the effective Young's modulus of the calcified matrix in the bisphosphonate treated groups. The observed increase in apparent Young's modulus was due to increased bone mass and altered trabecular architecture rather than changes in the calcified matrix modulus. We hypothesize that the expected increase in the Young's modulus of the calcified matrix due to the increased calcified matrix density was counteracted by the accumulation of microdamage.

  8. Formulation and stability of a soap microemulsion and the apparent pK(A) herein.

    Science.gov (United States)

    Marcus, Julien; Touraud, Didier; Kunz, Werner

    2013-10-01

    The influence of composition, and added salts and polyols on the stability of an oil-in-water microemulsion formulation and on the apparent pKA (apKA) of the used oleate surfactant is investigated. High temperature favours a decrease of the apKA and leads to the formation of more hydrated micelles. The apKA decreases also when the percentage of ethanol increases. Citronellol molecules do not significantly influence the apKA at concentrations between 0% and 2% w/w. By contrast, with increasing limonene concentration, the apKA increases. It was observed that anions of sodium salts destabilize the microemulsion and high temperatures are needed to recover it. By increasing the concentration of NaCl, a slight increase of the apKA is observed, which can be associated with a non-specific, electrostatic (Debye-Hückel) effect. Cations of chloride salts have different effects depending on their ability to exchange with Na(+) near the carboxylate group. Li(+), Na(+) and K(+) have apparently a salting-out effect. Tetramethylammonium chloride and choline chloride have salting-in effects until respectively 0.6 and 0.4 mol kg(-1). The associations of sorbitol or glycerol with ethanol lead to a salting-in effect and to a decrease of the apKA of Na-Oleate.

  9. Intake and total apparent digestibility in lambs fed six maize varieties in the Brazilian Semiarid

    Directory of Open Access Journals (Sweden)

    Rafael Dantas dos Santos

    2011-12-01

    Full Text Available The objective of this study was to evaluate the daily intake and total apparent digestibility of dry matter, organic matter, crude protein, gross energy, ether extract, neutral detergent fiber, acid detergent fiber, total and non-fibrous carbohydrates, total digestible nutrients, energy intake and nitrogen balance of silages of six maize varieties with early or super early cycles recommended to Northeast Brazil. Twenty-four male castrated lambs were lodged in metabolic cages. A completely randomized design with six treatments and four replications was used, with means compared by Tukey test at 5%. There were no differences among varieties for any of the evaluated variables regarding intake and apparent digestibility. Concerning the intake of digestible energy, metabolizable energy and the ratio content of digestible and metabolizable energy, significant differences were observed between varieties and BRS Assum Preto showed highest values of metabolizable energy (2.650,8 kcal/day. All of the treatments presented positive nitrogen balance and did not differ among themselves. The varieties asessed can be an additional option to the semiarid regions in Brazil.

  10. Regional and directional anisotropy of apparent diffusion coefficient in rat brain.

    Science.gov (United States)

    Hoehn-Berlage, M; Eis, M; Schmitz, B

    1999-02-01

    Quantitative diffusion maps were recorded in normal rat brain. In multi-slice sections covering the whole brain, strong variation of the apparent diffusion coefficient (ADC) was observed depending on slice position at constant gradient direction. Furthermore, a varying difference between apparent diffusion coefficients depending on gradient direction was found, reaching 32% in the cortex of the ventral-most horizontal sections while showing equal ADC on the dorsal cortex side. The regional variation and directional anisotropy of the ADC was not restricted to white matter but was described for both cortical and subcortical brain tissue. From diffusion coefficients along the three major field gradient directions (ADCx, ADCy, ADCz), the average ADC (ADCaverage) was determined from the trace of the diffusion tensor (D) as 653+/-28 microm2/s for parietal cortex and 671+/-32 microm2/s for lateral cortex, independent of position along the sagittal direction. From these observations about the regional diffusion anisotropy, a more stringent protocol for the description of ischemic ADC changes is proposed.

  11. Pseudomagnitudes and differential surface brightness: Application to the apparent diameter of stars

    Science.gov (United States)

    Chelli, Alain; Duvert, Gilles; Bourgès, Laurent; Mella, Guillaume; Lafrasse, Sylvain; Bonneau, Daniel; Chesneau, Olivier

    2016-05-01

    The diameter of a star is a major observable that serves to test the validity of stellar structure theories. It is also a difficult observable that is mostly obtained with indirect methods since the stars are so remote. Today only ~600 apparent star diameters have been measured by direct methods: optical interferometry and lunar occultations. Accurate star diameters are now required in the new field of exoplanet studies, since they condition the planets' sizes in transit observations, and recent publications illustrate a visible renewal of interest in this topic. Our analysis is based on the modeling of the relationship between measured angular diameters and photometries. It makes use of two new reddening-free concepts: a distance indicator called pseudomagnitude, and a quasi-experimental observable that is independent of distance and specific to each star, called the differential surface brightness (DSB). The use of all the published measurements of apparent diameters that have been collected so far, and a careful modeling of the DSB allow us to estimate star diameters with a median statistical error of 1.1%, knowing their spectral type and, in the present case, the VJHKs photometries. We introduce two catalogs, the JMMC Measured Diameters Catalog (JMDC), containing measured star diameters, and the second version of the JMMC Stellar Diameter Catalog (JSDC), augmented to about 453 000 star diameters. Finally, we provide simple formulas and a table of coefficients to quickly estimate stellar angular diameters and associated errors from (V, Ks) magnitudes and spectral types.

  12. Closer look at the effect of AFM imaging conditions on the apparent dimensions of surface nanobubbles.

    Science.gov (United States)

    Walczyk, Wiktoria; Schönherr, Holger

    2013-01-15

    To date, TM AFM (tapping mode or intermittent contact mode atomic force microscopy) is the most frequently applied direct imaging technique to visualize surface nanobubbles at the solid-aqueous interface. On one hand, AFM is the only profilometric technique that provides estimates of the bubbles' nanoscopic dimensions. On the other hand, the nanoscopic contact angles of surface nanobubbles estimated from their apparent dimensions that are deduced from AFM "height" images of nanobubbles differ markedly from the macrocopic water contact angles on the identical substrates. Here we show in detail how the apparent bubble height and width of surface nanobubbles on highly oriented pyrolytic graphite (HOPG) depend on the free amplitude of the cantilever oscillations and the amplitude setpoint ratio. (The role of these two AFM imaging parameters and their interdependence has not been studied so far for nanobubbles in a systematic way.) In all experiments, even with optimal scanning parameters, nanobubbles at the HOPG-water interface appeared to be smaller in the AFM images than their true size, which was estimated using a method presented herein. It was also observed that the severity of the underestimate increased with increasing bubble height and radius of curvature. The nanoscopic contact angle of >130° for nanobubbles on HOPG extrapolated to zero interaction force was only slightly overestimated and hence significantly higher than the macroscopic contact angle of water on HOPG (63 ± 2°). Thus, the widely reported contact angle discrepancy cannot be solely attributed to inappropriate AFM imaging conditions.

  13. Effect of N Fertilization on Grain Yield of Winter Wheat and Apparent N Losses

    Institute of Scientific and Technical Information of China (English)

    CUI Zhen-Ling; CHEN Xin-Ping; LI Jun-Liang; XU Jiu-Fei; SHI Li-Wei; ZHANG Fu-Suo

    2006-01-01

    Excessive nitrogen (N) fertilizer application to winter wheat is a common problem on the North China Plain. To determine the optimum fertilizer N rate for winter wheat production while minimizing N losses, field experiments were conducted for two growing seasons at eight sites, in Huimin County, Shandong Province, from 2001 to 2003. The optimum N rate for maximum grain yield was inversely related to the initial soil mineral N content (Nmin) in the top 90 cm of the soil profile before sowing. There was no yield response to the applied N at the three sites with high initial soil mineral N levels (average 212 kg N ha-1). The average optimum N rate was 96 kg N ha-1 for the five sites with low initial soil Nmin (average 155 kg N ha-1) before sowing. Residual nitrate N in the top 90 cm of the soil profile after harvest increased with increasing fertilizer N application rate. The apparent N losses during the wheat-growing season also increased with increasing N application rate. The average apparent N losses with the optimum N rates were less than 15 kg N ha-1,whereas the farmers' conventional N application rate resulted in losses of more than 100 kg N ha-1. Therefore, optimizing N use for winter wheat considerably reduced N losses to the environment without compromising crop yields.

  14. Systematics of RR Lyrae Statistical Parallax; 3, Apparent Magnitudes and Extinctions

    CERN Document Server

    Gould, A; Gould, Andrew; Popowski, Piotr

    1998-01-01

    We sing the praises of the central limit theorem. Having previously removed all other possible causes of significant systematic error in the statistical parallax determination of RR Lyrae absolute magnitudes, we investigate systematic errors from two final sources of input data: apparent magnitudes and extinctions. We find corrections due to each of ~0.05 mag, i.e., ~1/2 the statistical error. However, these are of opposite sign and so roughly cancel. The apparent magnitude system that we previously adopted from Layden et al. was calibrated to the photometry of Clube & Dawe. Using Hipparcos photometry we show that the Clube & Dawe system is ~0.06 mag too bright. Extinctions were previously pinned to the HI-based map of Burstein & Heiles. We argue that A_V should rather be based on new COBE/IRAS dust-emission map of Schlegel, Finkbeiner & Davis. This change increases the mean A_V by ~0.05 mag. We find M_V=0.77 +/- 0.13 at [Fe/H]=-1.60 for a pure sample of 147 halo RR Lyraes, or M_V=0.80 +/- 0.1...

  15. Fluorinated carbide-derived carbon: more hydrophilic, yet apparently more hydrophobic.

    Science.gov (United States)

    Farmahini, Amir H; Sholl, David S; Bhatia, Suresh K

    2015-05-13

    We explore the effect of fluorine doping on hydrophobicity of nanoporous silicon carbide-derived carbon (SiCDC), and investigate the underlying barriers for adsorption and diffusion of water vapor and CO2 in the fluorinated and nonfluorinated structures. We develop atomistic models of fluorine-doped SiCDC at three different levels of fluorination, based on a hybrid reverse Monte Carlo constructed model of SiCDC, and develop a novel first-principles force field for the simulation of adsorption and transport of water and CO2 in the fluorine-doped carbon materials. We demonstrate an apparent dual effect of fluorination, showing that while fluorination generates more hydrophilic carbon surfaces, they actually act as more hydrophobic structures due to enhanced energy barriers in the disordered network of microporous carbon. While an increase in adsorption energy and in water uptake is seen for fluorine-doped carbon, large internal free energy barriers as well as the results of MD simulations demonstrate that the increased adsorption is kinetically limited and not experimentally observable on practical time scales. We show that an increase in apparent hydrophobicity due to fluorination is mediated by larger free energy barriers arising from stronger binding of fluid molecules inside the pore network, as opposed to repulsion or steric hindrance to the diffusion of molecules through narrow pore entries. For carbon dioxide, adsorption enthalpies and activation energy barriers are both decreased on fluorination, indicating weakened solid-fluid binding energies in the fluorinated systems.

  16. Large apparent electric size of solid-state nanopores due to spatially extended surface conduction.

    Science.gov (United States)

    Lee, Choongyeop; Joly, Laurent; Siria, Alessandro; Biance, Anne-Laure; Fulcrand, Rémy; Bocquet, Lydéric

    2012-08-08

    Ion transport through nanopores drilled in thin membranes is central to numerous applications, including biosensing and ion selective membranes. This paper reports experiments, numerical calculations, and theoretical predictions demonstrating an unexpectedly large ionic conduction in solid-state nanopores, taking its origin in anomalous entrance effects. In contrast to naive expectations based on analogies with electric circuits, the surface conductance inside the nanopore is shown to perturb the three-dimensional electric current streamlines far outside the nanopore in order to meet charge conservation at the pore entrance. This unexpected contribution to the ionic conductance can be interpreted in terms of an apparent electric size of the solid-state nanopore, which is much larger than its geometric counterpart whenever the number of charges carried by the nanopore surface exceeds its bulk counterpart. This apparent electric size, which can reach hundreds of nanometers, can have a major impact on the electrical detection of translocation events through nanopores, as well as for ionic transport in biological nanopores.

  17. Apparent temperature anisotropies due to wave activity in the solar wind

    Directory of Open Access Journals (Sweden)

    E. Marsch

    2011-05-01

    Full Text Available The fast solar wind is a collisionless plasma permeated by plasma waves on many different scales. A plasma wave represents the natural interplay between the periodic changes of the electromagnetic field and the associated coherent motions of the plasma particles. In this paper, a model velocity distribution function is derived for a plasma in a single, coherent, large-amplitude wave. This model allows one to study the kinetic effects of wave motions on particle distributions. They are by in-situ spacecraft measured by counting, over a certain sampling time, the particles coming from various directions and having different energies. We compare our results with the measurements by the Helios spacecraft, and thus find that by assuming high wave activity we are able to explain key observed features of the measured distributions within the framework of our model. We also address the recent discussions on nonresonant wave–particle interactions and apparent heating. The applied time-averaging procedure leads to an apparent ion temperature anisotropy which is connected but not identical to the intrinsic temperature of the underlying distribution function.

  18. Why does the apparent mass of a coronal mass ejection increase?

    CERN Document Server

    Feng, Li; Shen, Fang; Shen, Chenglong; Inhester, Bernd; Lu, Lei; Gan, Weiqun

    2015-01-01

    Mass is one of the most fundamental parameters characterizing the dynamics of a coronal mass ejection (CME). It has been found that CME apparent mass measured from the brightness enhancement in coronagraph images shows an increasing trend during its evolution in the corona. However, the physics behind it is not clear. Does the apparent mass gain come from the mass outflow from the dimming regions in the low corona, or from the pileup of the solar wind plasma around the CME when it propagates outwards from the Sun? We analyzed the mass evolution of six CME events. Their mass can increase by a factor of 1.6 to 3.2 from 4 to 15 Rs in the field of view (FOV) of the coronagraph on board the Solar Terrestrial Relations Observatory (STEREO). Over the distance about 7 to 15 Rs, where the coronagraph occulting effect can be negligible, the mass can increase by a factor of 1.3 to 1.7. We adopted the `snow-plough' model to calculate the mass contribution of the piled-up solar wind in the height range from about 7 to 15 ...

  19. Comparison of selenite and selenate apparent absorption and retention in infants using stable isotope methodology.

    Science.gov (United States)

    Van Dael, Peter; Davidsson, Lena; Ziegler, Ekhard E; Fay, Laurent B; Barclay, Denis

    2002-01-01

    The inorganic selenium compounds selenite and selenate are used for selenium fortification of infant formulas. However, information on absorption and retention of selenium from these compounds is lacking. The purpose of this study was therefore to determine apparent absorption and retention of selenium from selenate and selenite added to a milk-based infant formula in healthy infants. Labeled test meals were prepared by addition of 10 microg Se as (76)Se-selenate or (74)Se-selenite to 500 mL formula. The two batches of labeled formulas were fed as alternate feeds during the first day of the balance period, followed by unlabeled formula. Selenium isotopes were determined in feces collected for 72h after intake and in 3 consecutive 24h collections of urine. Mean apparent absorption was 97.1% for (76)Se-selenate and 73.4% for (74)Se-selenite; mean difference 23.7% (range: 13.8%-35.7%; SD 6.8%, p absorption and urinary excretion differed for selenite and selenate, selenium was equally well retained by infants from both selenium compounds. We therefore concluded that Se fortification of infant formulas with selenate or selenite can be expected to have similar impact on the selenium nutritional status of term infants.

  20. Impact of Apparent Reactance Injected by TCSR on Distance Relay in Presence Phase to Earth Fault

    Directory of Open Access Journals (Sweden)

    Mohamed Zellagui

    2013-01-01

    Full Text Available This research paper presents the impact study of apparent reactance injected by series Flexible AC Transmission System (FACTS i.e. Thyristor Controlled Series Reactor (TCSR on the measured impedance of a 400 kV single electrical transmission line in the presence of phase to earth fault with fault resistance. The study deals with an electrical transmission line of Eastern Algerian transmission networks at Group Sonelgaz (Algerian Company of Electrical compensated by TCSR connected at midpoint of the transmission line. This compensator used to inject voltage and reactive power is controlled by TCSR. The simulations results investigate the three impacts of the apparent reactance injected by TCSR (XTCSR on transmission line protected by distance relay protection. The impacts concern the active and reactive power, the line impedance (reactance and resistance, and the short circuit parameters (symmetrical currents, line currents, symmetrical voltages and line voltages as well as the measured impedance by relay (resistance and reactance in the presence of earth fault These impacts are investigated in order to improve the performances of distance relay protection. More the impact of XTCSR by three TCSR for cases studies is presented.

  1. Influence of surface conductivity on the apparent zeta potential of calcite.

    Science.gov (United States)

    Li, Shuai; Leroy, Philippe; Heberling, Frank; Devau, Nicolas; Jougnot, Damien; Chiaberge, Christophe

    2016-04-15

    Zeta potential is a physicochemical parameter of particular importance in describing the surface electrical properties of charged porous media. However, the zeta potential of calcite is still poorly known because of the difficulty to interpret streaming potential experiments. The Helmholtz-Smoluchowski (HS) equation is widely used to estimate the apparent zeta potential from these experiments. However, this equation neglects the influence of surface conductivity on streaming potential. We present streaming potential and electrical conductivity measurements on a calcite powder in contact with an aqueous NaCl electrolyte. Our streaming potential model corrects the apparent zeta potential of calcite by accounting for the influence of surface conductivity and flow regime. We show that the HS equation seriously underestimates the zeta potential of calcite, particularly when the electrolyte is diluted (ionic strength ⩽ 0.01 M) because of calcite surface conductivity. The basic Stern model successfully predicted the corrected zeta potential by assuming that the zeta potential is located at the outer Helmholtz plane, i.e. without considering a stagnant diffuse layer at the calcite-water interface. The surface conductivity of calcite crystals was inferred from electrical conductivity measurements and computed using our basic Stern model. Surface conductivity was also successfully predicted by our surface complexation model.

  2. Nutrients can modulate the adiponectin concentrations in apparently healthy young adults

    Directory of Open Access Journals (Sweden)

    Ana Carolina Pinheiro Volp

    Full Text Available Introduction: Adiponectin, an adipocyte derived peptide, has anti-inflammatory and antiatherogenic effects, and improves insulin sensitivity. However, little is known about dietary predictors and their interactions with lifestyle on adiponectin concentrations, in apparently healthy young adults. Objective: To evaluate the associations between plasma concentrations of adiponectin with dietary components and lifestyle in apparently healthy young adults. Methods: Anthropometric and body composition, systolic and diastolic blood pressure, diet and lifestyle data of 157 healthy young adults, aged 18 and 35, were collected and analyzed. Blood samples were collected after fasting for 12 hours to determine adiponectin concentrations. Dietary and anthropometric indexes were calculated and analyzed. Results: Adiponectin concentrations were significantly higher for women compared to men; and there was an indirect and significant correlation between adiponectin concentrations with BMI. There was a significant association between adiponectin concentrations with the healthy eating index, calories, lipids, proteins, fibers, riboflavin, and phosphorus, among others; and a tendency with carbohydrates and niacin. In multiple linear regression analysis, fiber and riboflavin (r² = 0.0928; p = 0.0013 and carbohydrates and phosphorus were associated with the concentrations of adiponectin. The association with carbohydrates and phosphorus suffered interaction with gender (r²= 0.2400; p < 0.0001, as well as the association with phosphorus also suffered interaction with physical activity (r²= 0.1275; p = 0.0003. Conclusion: Plasma concentrations of adiponectin, in healthy young adults, seem to be modulated by components of diet depending on gender and physical activity.

  3. Comparison of apparent ileal amino acid digestibility of feed ingredients measured with broilers, layers, and roosters.

    Science.gov (United States)

    Huang, K H; Li, X; Ravindran, V; Bryden, W L

    2006-04-01

    The apparent ileal digestibility of amino acids in 7 feed ingredients was determined using broilers, layers, and roosters. The ingredients included 3 cereals (wheat, sorghum, and corn), 3 oilseed meals (canola, cottonseed, and soybean meals), and 1 animal protein meal (meat and bone meal). Dietary protein in the assay diets was supplied solely by the test ingredient. All diets contained 20 g/kg of acid-insoluble ash as an indigestible marker, and each diet was offered ad libitum in mash form to 5 replicate pens of broilers and layers, and 4 replicate pens of roosters. The digestibility coefficients of individual amino acids for wheat, corn, and sorghum were higher (P meal, cottonseed meal, and meat and bone meal was similar among the 3 classes of chickens. The digestibility of amino acids in soybean meal was higher (P < 0.05) for layers compared with those for broilers and roosters but similar between broilers and roosters. These results suggest that the class of chickens significantly influenced the apparent ileal digestibility of amino acids in some feed ingredients.

  4. HARNESSING BIG DATA VOLUMES

    Directory of Open Access Journals (Sweden)

    Bogdan DINU

    2014-04-01

    Full Text Available Big Data can revolutionize humanity. Hidden within the huge amounts and variety of the data we are creating we may find information, facts, social insights and benchmarks that were once virtually impossible to find or were simply inexistent. Large volumes of data allow organizations to tap in real time the full potential of all the internal or external information they possess. Big data calls for quick decisions and innovative ways to assist customers and the society as a whole. Big data platforms and product portfolio will help customers harness to the full the value of big data volumes. This paper deals with technical and technological issues related to handling big data volumes in the Big Data environment.

  5. Volumes of chain links

    CERN Document Server

    Kaiser, James; Rollins, Clint

    2011-01-01

    Agol has conjectured that minimally twisted n-chain links are the smallest volume hyperbolic manifolds with n cusps, for n at most 10. In his thesis, Venzke mentions that these cannot be smallest volume for n at least 11, but does not provide a proof. In this paper, we give a proof of Venzke's statement. The proof for n at least 60 is completely rigorous. The proof for n between 11 and 59 uses a computer calculation, and can be made rigorous for manifolds of small enough complexity, using methods of Moser and Milley. Finally, we prove that the n-chain link with 2m or 2m+1 half-twists cannot be the minimal volume hyperbolic manifold with n cusps, provided n is at least 60 or |m| is at least 8, and we give computational data indicating this remains true for smaller n and |m|.

  6. The volume of a soliton

    Energy Technology Data Exchange (ETDEWEB)

    Adam, C., E-mail: adam@fpaxp1.usc.es [Departamento de Física de Partículas, Universidad de Santiago de Compostela and Instituto Galego de Física de Altas Enerxias (IGFAE), E-15782 Santiago de Compostela (Spain); Haberichter, M. [School of Mathematics, Statistics and Actuarial Science, University of Kent, Canterbury, CT2 7NF (United Kingdom); Wereszczynski, A. [Institute of Physics, Jagiellonian University, Lojasiewicza 11, Kraków (Poland)

    2016-03-10

    There exists, in general, no unique definition of the size (volume, area, etc., depending on dimension) of a soliton. Here we demonstrate that the geometric volume (area etc.) of a soliton is singled out in the sense that it exactly coincides with the thermodynamical or continuum-mechanical volume. In addition, this volume may be defined uniquely for rather arbitrary solitons in arbitrary dimensions.

  7. Animal Science Technology. An Experimental Developmental Program. Volume I, Report of the Developmental Program.

    Science.gov (United States)

    Brant, Herman G.; And Others

    In 1961, administrative personnel at Delhi College in New York observed that formal training programs for animal science technicians were virtually nonexistant. Response to this apparent need resulted in the initiation of perhaps the first 2-year Animal Science Technology Program in the nation. This two-volume report is the result of an extensive…

  8. Topological Active Volumes

    Directory of Open Access Journals (Sweden)

    Barreira N

    2005-01-01

    Full Text Available The topological active volumes (TAVs model is a general model for 3D image segmentation. It is based on deformable models and integrates features of region-based and boundary-based segmentation techniques. Besides segmentation, it can also be used for surface reconstruction and topological analysis of the inside of detected objects. The TAV structure is flexible and allows topological changes in order to improve the adjustment to object's local characteristics, find several objects in the scene, and identify and delimit holes in detected structures. This paper describes the main features of the TAV model and shows its ability to segment volumes in an automated manner.

  9. Aperiodic Volume Optics

    Science.gov (United States)

    Gerke, Tim D.

    Presented in this thesis is an investigation into aperiodic volume optical devices. The three main topics of research and discussion are the aperiodic volume optical devices that we call computer-generated volume holograms (CGVH), defects within periodic 3D photonic crystals, and non-periodic, but ordered 3D quasicrystals. The first of these devices, CGVHs, are designed and investigated numerically and experimentally. We study the performance of multi-layered amplitude computer-generated volume holograms in terms of efficiency and angular/frequency selectivity. Simulation results show that such aperiodic devices can increase diffraction efficiency relative to periodic amplitude volume holograms while maintaining angular and wavelength selectivity. CGVHs are also designed as voxelated volumes using a new projection optimization algorithm. They are investigated using a volumetric diffraction simulation and a standard 3D beam propagation technique as well as experimentally. Both simulation and experiment verify that the structures function according to their design. These represent the first diffractive structures that have the capacity for generating arbitrary transmission and reflection wave fronts and that provide the ability for multiplexing arbitrary functionality given different illumination conditions. Also investigated and discussed in this thesis are 3D photonic crystals and quasicrystals. We demonstrate that these devices can be fabricated using a femtosecond laser direct writing system that is particularly appropriate for fabrication of such arbitrary 3D structures. We also show that these devices can provide 3D partial bandgaps which could become complete bandgaps if fabricated using high index materials or by coating lower index materials with high index metals. Our fabrication method is particularly suited to the fabrication of engineered defects within the periodic or quasi-periodic systems. We demonstrate the potential for fabricating defects within

  10. Apparent density of the primate calcaneo-cuboid joint and its association with locomotor mode, foot posture, and the "midtarsal break".

    Science.gov (United States)

    Nowak, Matthew G; Carlson, Kristian J; Patel, Biren A

    2010-06-01

    Primates use a range of locomotor modes during which they incorporate various foot postures. Humans are unique compared with other primates in that humans lack a mobile fore- and midfoot. Rigidity in the human foot is often attributed to increased propulsive and stability requirements during bipedalism. Conversely, fore- and midfoot mobility in nonhuman primates facilitates locomotion in arboreal settings. Here, we evaluated apparent density (AD) in the subchondral bone of human, ape, and monkey calcanei exhibiting different types of foot loading. We used computed tomography osteoabsorptiometry and maximum intensity projection (MIP) maps to visualize AD in subchondral bone at the cuboid articular surface of calcanei. MIPs represent 3D volumes (of subchondral bone) condensed into 2D images by extracting AD maxima from columns of voxels comprising the volumes. False-color maps are assigned to MIPs by binning pixels in the 2D images according to brightness values. We compared quantities and distributions of AD pixels in the highest bin to test predictions relating AD patterns to habitual locomotor modes and foot posture categories of humans and several nonhuman primates. Nonhuman primates exhibit dorsally positioned high AD concentrations, where maximum compressive loading between the calcaneus and cuboid likely occurs during "midtarsal break" of support. Humans exhibit less widespread areas of high AD, which could reflect reduced fore- and midfoot mobility. Analysis of the internal morphology of the tarsus, such as subchondral bone AD, potentially offers new insights for evaluating primate foot function during locomotion.

  11. Correlation between 3 T apparent diffusion coefficient values and grading of invasive breast carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Cipolla, Valentina, E-mail: valentina.cipolla@yahoo.it [Department of Radiological Sciences, University of Rome “Sapienza”, Viale del Policlinico 155, 00161 Rome (Italy); Santucci, Domiziana; Guerrieri, Daniele; Drudi, Francesco Maria [Department of Radiological Sciences, University of Rome “Sapienza”, Viale del Policlinico 155, 00161 Rome (Italy); Meggiorini, Maria Letizia [Department of Gynaecological Sciences, University of Rome “Sapienza”, Viale del Policlinico 155, 00161 Rome (Italy); Felice, Carlo de [Department of Radiological Sciences, University of Rome “Sapienza”, Viale del Policlinico 155, 00161 Rome (Italy)

    2014-12-15

    Highlights: • Apparent diffusion coefficient is a quantitative parameter which reflects molecular water movement. • Grading is an independent prognostic factor which correlates with other histopathological features. • Apparent diffusion coefficient values were significantly different between G1 and G3 classes. - Abstract: Purpose: The aim of this study was to evaluate whether the apparent diffusion coefficient (ADC) provided by 3.0 T (3 T) magnetic resonance diffusion-weighted imaging (DWI) varied according to the grading of invasive breast carcinoma. Materials and methods: A total of 92 patients with 96 invasive breast cancer lesions were enrolled; all had undergone 3 T magnetic resonance imaging (MRI) for local staging. All lesions were confirmed by histological analysis, and tumor grade was established according to the Nottingham Grading System (NGS). MRI included both dynamic contrast-enhanced and DWI sequences, and ADC value was calculated for each lesion. ADC values were compared with NGS classification using the Mann–Whitney U and the Kruskal–Wallis H tests. Grading was considered as a comprehensive prognostic factor, and Rho Spearman test was performed to determine correlation between grading and tumor size, hormonal receptor status, HER2 expression and Ki67 index. Pearson's Chi square test was carried out to compare grading with the other prognostic factors. Results: ADC values were significantly higher in G1 than in G3 tumors. No significant difference was observed when G1 and G3 were compared with G2. Tumor size, hormonal receptor status, HER2 expression and Ki67 index correlated significantly with grading but there was a significant difference only between G1 and G3 related to the ER and PR status, HER2 expression and Ki67 index. There was no statistically significant difference in lesion size between the two groups. Conclusion: ADC values obtained on 3 T DWI correlated with low-grade (G1) and high-grade (G3) invasive breast carcinoma. 3

  12. Apparent topologically forbidden interchange of energy surfaces under slow variation of a Hamiltonian.

    Science.gov (United States)

    Lu, Zhixin; Jarzynski, Christopher; Ott, Edward

    2015-05-01

    In this paper we consider the motion of point particles in a particular type of one-degree-of-freedom, slowly changing, temporally periodic Hamiltonian. Through most of the time cycle, the particles conserve their action, but when a separatrix is approached and crossed, the conservation of action breaks down, as shown in previous theoretical studies. These crossings have the effect that the numerical solution shows an apparent contradiction. Specifically we consider two initial constant energy phase space curves H=E(A) and H=E(B) at time t=0, where H is the Hamiltonian and E(A) and E(B) are the two initial energies. The curve H=E(A) encircles the curve H=E(B). We then sprinkle many initial conditions (particles) on these curves and numerically follow their orbits from t=0 forward in time by one cycle period. At the end of the cycle the vast majority of points initially on the curves H=E(A) and H=E(B) now appear to lie on two new constant energy curves H=E(A)' and H=E(B)', where the B' curve now encircles the A' curve (as opposed to the initial case where the A curve encircles the B curve). Due to the uniqueness of Hamilton dynamics, curves evolved under the dynamics cannot cross each other. Thus the apparent curves H=E(A)' and H=E(B)' must be only approximate representations of the true situation that respects the topological exclusion of curve crossing. In this paper we resolve this apparent paradox and study its consequences. For this purpose we introduce a "robust" numerical simulation technique for studying the complex time evolution of a phase space curve in a Hamiltonian system. We also consider how a very tiny amount of friction can have a major consequence, as well as what happens when a very large number of cycles is followed. We also discuss how this phenomenon might extend to chaotic motion in higher dimensional Hamiltonian systems.

  13. Occurrence of African horse sickness in a domestic dog without apparent ingestion of horse meat

    Directory of Open Access Journals (Sweden)

    Sybrand J. van Sittert

    2013-02-01

    Full Text Available This is the first case of African horse sickness (AHS in a dog where there was no apparent ingestion of horse meat. Significantly, the dog was part of a colony that resides in a Good Clinical Practice and Good Laboratory Practice accredited facility where complete history, weather and feeding records are maintained. The dog died after a week-long illness despite therapy. The principal post-mortem findings were severe hydrothorax and pulmonary consolidation (red hepatisation of the lungs. Histopathology revealed severe oedema and congestion of the lungs, hyaline degeneration of the myocardium and congestion of the liver sinusoids. Immunohistochemistry detected AHS-positive staining granules in the myocardium, whilst a real-time reverse transcription quantitative Polymerase chain reaction assay of tissue samples was strongly positive for African horse sickness virus nucleic acid. Other dogs on the property showed a 43%seroconversion rate to AHS.

  14. Constitutive Description of 7075 Aluminum Alloy During Hot Deformation by Apparent and Physically-Based Approaches

    Science.gov (United States)

    Mirzadeh, Hamed

    2015-03-01

    Hot flow stress of 7075 aluminum alloy during compressive hot deformation was correlated to the Zener-Hollomon parameter through constitutive analyses based on the apparent approach and the proposed physically-based approach which accounts for the dependence of the Young's modulus and the self-diffusion coefficient of aluminum on temperature. It was shown that the latter approach not only results in a more reliable constitutive equation, but also significantly simplifies the constitutive analysis, which in turn makes it possible to conduct comparative hot working studies. It was also demonstrated that the theoretical exponent of 5 and the lattice self-diffusion activation energy of aluminum (142 kJ/mol) can be set in the hyperbolic sine law to describe the peak flow stresses and the resulting constitutive equation was found to be consistent with that resulted from the proposed physically-based approach.

  15. Decreased trabecular bone biomechanical competence, apparent density, IGF-II and IGFBP-5 content in acromegaly

    DEFF Research Database (Denmark)

    Ueland, Thor; Ebbesen, Ebbe Nils; Thomsen, Jesper Skovhus;

    2002-01-01

    of these growth factors in relation to biomechanical properties in acromegaly. MATERIALS AND METHODS: Trabecular bone biomechanical competence (compression test), apparent density (peripheral quantitative computed tomography, pQCT), and bone matrix contents of calcium (HCl hydrolysis) and IGFs (guanidinium......-HCl extraction) were measured in iliac crest biopsies from 13 patients with active acromegaly (two women and 11 men, aged 21-61 years) and 21 age- and sex-matched controls (four women and 17 men, aged 23-64 years). RESULTS: Trabecular bone pQCT was reduced in acromegalic patients compared with controls (P = 0...... bone content of IGF-I, IGFBP-3, or osteocalcin. However, IGF-II and IGFBP-5 content was decreased (P acromegaly, supporting previous observations...

  16. Global Lithospheric Apparent Susceptibility Distribution Converted from Geomagnetic Models by CHAMP and Swarm Satellite Magnetic Measurements

    Science.gov (United States)

    Du, Jinsong; Chen, Chao; Xiong, Xiong; Li, Yongdong; Liang, Qing

    2016-04-01

    Recently, because of continually accumulated magnetic measurements by CHAMP satellite and Swarm constellation of three satellites and well developed methodologies and techniques of data processing and geomagnetic field modeling etc., global lithospheric magnetic anomaly field models become more and more reliable. This makes the quantitative interpretation of lithospheric magnetic anomaly field possible for having an insight into large-scale magnetic structures in the crust and uppermost mantle. Many different approaches have been utilized to understand the magnetized sources, such as forward, inversion, statistics, correlation analysis, Euler deconvolution, signal transformations etc. Among all quantitative interpretation methods, the directly converting a magnetic anomaly map into a magnetic susceptibility anomaly map proposed by Arkani-Hamed & Strangway (1985) is, we think, the most fast quantitative interpretation tool for global studies. We just call this method AS85 hereinafter for short. Although Gubbins et al. (2011) provided a formula to directly calculate the apparent magnetic vector distribution, the AS85 method introduced constraints of magnetized direction and thus corresponding results are expected to be more robust especially in world-wide continents. Therefore, in this study, we first improved the AS85 method further considering non-axial dipolar inducing field using formulae by Nolte & Siebert (1987), initial model or priori information for starting coefficients in the apparent susceptibility conversion, hidden longest-wavelength components of lithospheric magnetic field and field contaminations from global oceanic remanent magnetization. Then, we used the vertically integrated susceptibility model by Hemant & Maus (2005) and vertically integrated remanent magnetization model by Masterton et al. (2013) to test the validity of our improved method. Subsequently, we applied the conversion method to geomagnetic field models by CHAMP and Swarm satellite

  17. Apparent diffusion coefficient ratio correlates significantly with prostate cancer gleason score at final pathology

    DEFF Research Database (Denmark)

    Boesen, Lars; Chabanova, Elizaveta; Løgager, Vibeke;

    2015-01-01

    PURPOSE: To evaluate the correlation between apparent diffusion coefficient measurements (ADCtumor and ADCratio ) and the Gleason score from radical prostatectomy specimens. MATERIALS AND METHODS: Seventy-one patients with clinically localized prostate cancer scheduled for radical prostatectomy...... correlated with the Gleason score from the prostatectomy specimens. RESULTS: The association between ADC measurements and Gleason score showed a significant negative correlation (P ... between ADC measurements and the Gleason score for all tumors (P = 0.001). Receiver operating characteristic curve analysis showed an overall area under the curve (AUC) of 0.73 (ADCtumor ) to 0.80 (ADCratio ) in discriminating Gleason score 6 from Gleason score ≥7 tumors. The AUC changed to 0.72 (ADCtumor...

  18. Des apparences fantasmées dans les fabliaux érotiques

    Directory of Open Access Journals (Sweden)

    Sophie Poitral

    2008-08-01

    Full Text Available Résumé : Composés de la fin du XIIe siècle au XIVe siècle, les fabliaux érotiques posent la question du corps et de son langage. Ses composantes - vêtement, physionomie, allure et gestuelle - participent à la duperie qui caractérise bien souvent l’univers des fabliaux. L’analyse des emplois de l’apparence dans quelques fabliaux érotiques français, aux auteurs anonymes ou connus, permet de définir le rôle central des apparences dans les stratagèmes mis en œuvre et montre la richesse des enjeux du paraître dans l’érotisme occidental du Moyen Âge : le travestissement sexuel est traité de manières différentes selon les sexes. L’apparence féminine de l’homme leurre le mari et permet à la femme rusée de commettre l’adultère, tandis que la femme travestie en homme soulève la question du pouvoir et du sexe dans la relation conjugale et dans la société. D’autre part, le déguisement parodique masque l’identité de celui qui trompe par ses faux-semblants et accumule les situations carnavalesques qui tournent à l’avantage de l’imposteur. Le mirage érotique met quant à lui en question le regard du voyeur, victime d’une illusion d’optique, et enfin le langage métamorphose l’apparence des organes sexuels, aux dépens des jeunes filles innocentes.Abstract : Analysing fantasised appearances in erotic fabliaux Erotic fabliaux, poems composed from the late 12th to the 14th century, bring into focus the question of the body and its language. Its various constituents - clothes, physionomy, bearing and body movements - all contribute to producing the deceit which is so characteristic of the world of fabliaux. Analysing how looks are exploited in a couple of French fabliaux both by unknown or renowned writers enables us better to define the key function of looks in the various strategies thus developed and to see just how complex and fundamental questions of aspect are in medieval western eroticism

  19. Circadian aspects of apparent correlation dimension in human heart rate dynamics.

    Science.gov (United States)

    Van Leeuwen, P; Bettermann, H; An der Heiden, U; Kümmell, H C

    1995-07-01

    The purpose of this study was to examine changes in complexity of cardiac dynamics over 24 h. With use of Holter monitoring, 27 24-h electrocardiogram recordings were obtained from 15 healthy subjects. For each recording, the apparent dimension (DA) was calculated for consecutive sections of 500 heartbeats. These were used to determine nighttime and daytime dimension (D(An) and D(Ad), respectively) as well as the difference between D(An) and D(Ad) (delta DA). Mean 24-h DA, D(An), and D(Ad) were 5.9 +/- 0.3, 6.3 +/- 0.5, and 5.6 +/- 0.6, respectively. D(An) was significantly higher than D(Ad) (P heart rate complexity. We suggest that the decreased complexity during daytime may result from the synchronization of physiological functions. The increase in complexity at night would then correspond to an uncoupling of these functions during the regenerative period.

  20. Bisphosphonate treatment affects trabecular bone apparent modulus through micro-architecture rather than matrix properties

    DEFF Research Database (Denmark)

    Ding, Ming

    2004-01-01

    and trabecular architecture independently. Conventional histomorphometry and microdamage data were obtained from the second and third lumbar vertebrae of the same dogs [Bone 28 (2001) 524]. Bisphosphonate treatment resulted in an increased apparent Young's modulus, decreased bone turnover, increased calcified......Bisphosphonates are emerging as an important treatment for osteoporosis. But whether the reduced fracture risk associated with bisphosphonate treatment is due to increased bone mass, improved trabecular architecture and/or increased secondary mineralization of the calcified matrix remains unclear....... We examined the effects of bisphosphonates on both the trabecular architecture and matrix properties of canine trabecular bone. Thirty-six beagles were divided into a control group and two treatment groups, one receiving risedronate and the other alendronate at 5-6 times the clinical dose...

  1. Evidence of deterministic components in the apparent randomness of GRBs: clues of a chaotic dynamic.

    Science.gov (United States)

    Greco, G; Rosa, R; Beskin, G; Karpov, S; Romano, L; Guarnieri, A; Bartolini, C; Bedogni, R

    2011-01-01

    Prompt γ-ray emissions from gamma-ray bursts (GRBs) exhibit a vast range of extremely complex temporal structures with a typical variability time-scale significantly short - as fast as milliseconds. This work aims to investigate the apparent randomness of the GRB time profiles making extensive use of nonlinear techniques combining the advanced spectral method of the Singular Spectrum Analysis (SSA) with the classical tools provided by the Chaos Theory. Despite their morphological complexity, we detect evidence of a non stochastic short-term variability during the overall burst duration - seemingly consistent with a chaotic behavior. The phase space portrait of such variability shows the existence of a well-defined strange attractor underlying the erratic prompt emission structures. This scenario can shed new light on the ultra-relativistic processes believed to take place in GRB explosions and usually associated with the birth of a fast-spinning magnetar or accretion of matter onto a newly formed black hole.

  2. Elastic scattering by hot electrons and apparent lifetime of longitudinal optical phonons in gallium nitride

    Energy Technology Data Exchange (ETDEWEB)

    Khurgin, Jacob B., E-mail: jakek@jhu.edu [Department of Electrical and Computer Engineering, Johns Hopkins University, Baltimore, Maryland 21218 (United States); Bajaj, Sanyam; Rajan, Siddharth [Department of Electrical and Computer Engineering, The Ohio State University, Columbus, Ohio 43210 (United States)

    2015-12-28

    Longitudinal optical (LO) phonons in GaN generated in the channel of high electron mobility transistors (HEMT) are shown to undergo nearly elastic scattering via collisions with hot electrons. The net result of these collisions is the diffusion of LO phonons in the Brillouin zone causing reduction of phonon and electron temperatures. This previously unexplored diffusion mechanism explicates how an increase in electron density causes reduction of the apparent lifetime of LO phonons, obtained from the time resolved Raman studies and microwave noise measurements, while the actual decay rate of the LO phonons remains unaffected by the carrier density. Therefore, the saturation velocity in GaN HEMT steadily declines with increased carrier density, in a qualitative agreement with experimental results.

  3. Diagnosis and management of "an apparent mechanical" femoral mononeuropathy: a case study.

    Science.gov (United States)

    Desmarais, Ariane; Descarreaux, Martin

    2007-12-01

    This report describes an apparent case of femoral nerve mononeuropathy in a 58-year-old equestrian due to mechanical stress. A woman presented at a chiropractic office complaining of right buttock pain radiating to the right groin and knee. A treatment plan, consisting of chiropractic adjustments in addition to stretching and myofascial therapy, was initiated. The goal was to reduce pain and inflammation in the sacroiliac articulation by restoring normal biomechanical function. A rehabilitation program to alleviate tension in the musculature was initiated to reduce mechanical stresses exerted on the femoral nerve. The patient received five treatments over a period of three weeks and became asymptomatic. Even though peripheral nerve entrapment is an uncommon condition, clinicians must not overlook the possibility of a femoral mononeuropathy as it can produce a complex presentation and lead to ineffective patient management.

  4. Is Quantum Suicide Painless? On an Apparent Violation of The Principal Principle

    CERN Document Server

    Cirkovic, M M

    2004-01-01

    The experimental setup of the self-referential quantum measurement, jovially known as the "quantum suicide" or the "quantum Russian roulette" is analyzed from the point of view of the Principal Principle of David Lewis. It is shown that the apparent violation of this principle--relating objective probabilities and subjective chance--in this type of thought experiment is just an illusion due to the usage of some terms and concepts ill-defined in the quantum context. We conclude that even in the case that Everett's (or some other "no-collapse") theory is a correct description of reality, we can coherently believe in equating subjective credence with objective chance in quantum-mechanical experiments. This is in agreement with results of the research on personal identity in the quantum context by Parfit and Tappenden.

  5. No apparent lock-in depth of the Laschamp geomagnetic excursion: Evidence from the Malan loess

    Institute of Scientific and Technical Information of China (English)

    ZHU Rixiang; LIU Qingsong; PAN Yongxin; DENG Chenglong; ZHANG Rui; WANG Xianfeng

    2006-01-01

    The first-order chronological framework of the long-term Chinese loess/paleosol sequences was based mainly on magnetostratigraphy. However, there remain arguments on the lock-in ages of the major geomagnetic reversals. This study systematically compared the stratigraphic locations of the Laschamp excursion and Henrich events (H4 at~39 ka and H5 at~48 ka) recorded by the Luochuan loess profile in the central Chinese Loess Plateau. Results show that the Lascchamp excursion is bracketed well by these two cold events, and the corresponding estimated age is between about 41.7-43.7 ka, which is close to the widely accepted age of ~40-41 ka for the excursion.Therefore, our new results do not suggest apparent lock-in effects in the last glacial Malan loess.

  6. Elastic scattering by hot electrons and apparent lifetime of longitudinal optical phonons in gallium nitride

    Science.gov (United States)

    Khurgin, Jacob B.; Bajaj, Sanyam; Rajan, Siddharth

    2015-12-01

    Longitudinal optical (LO) phonons in GaN generated in the channel of high electron mobility transistors (HEMT) are shown to undergo nearly elastic scattering via collisions with hot electrons. The net result of these collisions is the diffusion of LO phonons in the Brillouin zone causing reduction of phonon and electron temperatures. This previously unexplored diffusion mechanism explicates how an increase in electron density causes reduction of the apparent lifetime of LO phonons, obtained from the time resolved Raman studies and microwave noise measurements, while the actual decay rate of the LO phonons remains unaffected by the carrier density. Therefore, the saturation velocity in GaN HEMT steadily declines with increased carrier density, in a qualitative agreement with experimental results.

  7. PG 1002+506: a Be Star Apparently at Z > +10 KPC

    Science.gov (United States)

    Ringwald, F. A.; Rolleston, W. R. J.; Saffer, R. A.; Thorstensen, John R.

    1997-12-01

    PG 1002+506 is found to be a Be star, one of two so far found by the Palomar-Green survey. Its spectrum is classified as a B5+/- 1 Ve, with T_eff = 14,900 +/- 1200, log g = 4.2 +/- 0.2, and v sin i = 340 +/- 50 km s(-1) . At b = +51(deg) , its height above the Galactic plane would therefore be Z = +10.8 kpc, putting this apparently young, rapidly rotating star well into the Galactic halo. Its heliocentric radial velocity is found to be -2 +/- 15 km s(-1) , consistent with either having been formed in the Galactic disk and subsequently ejected, or having been formed in the halo.

  8. Apparent Contact Angle Calculated from a Water Repellent Model with Pinning Effect.

    Science.gov (United States)

    Suzuki, Shojiro; Ueno, Kazuyuki

    2017-01-10

    A set of new theoretical equations for apparent contact angles is proposed. The equations are derived from an equilibrium of interfacial tensions of a three-phase contact line pinned at the edges of a fine structure. These equations are validated by comparison with contact-angle measurement results for 2 μL water droplets on poly(methyl methacrylate) microstructured samples with square pillars or holes. The equilibrium contact angles predicted by the new equations reasonably agree with the experimental results. In contrast, the values predicted by the Cassie-Baxter equation or the Wenzel equation do not qualitatively agree with the experimental results in pillar pattern cases because the Cassie-Baxter equation and the Wenzel equation do not account for the pinning effect.

  9. Numerical estimation of real and apparent integral neutron parameters used in nuclear borehole geophysics.

    Science.gov (United States)

    Dworak, D; Drabina, A; Woźnicka, U

    2006-07-01

    The semi-empirical method of neutron logging tool calibration developed by Prof. J.A. Czubek uses the real and so-called apparent integral neutron parameters of geological formations. To this end, Czubek proposed a few separated calculation methods commonly based on analytical solutions of the neutron transport problem. A new calculation method for the neutron integral parameters is proposed. Quantities like slowing-down length, diffusion and migration lengths, probability to avoid absorption during slowing down, and thermal neutron absorption cross section can be easily approximated using Monte Carlo simulations. A comparison with the results of the analytical method developed by Czubek has been performed for many cases and the observed differences have been explained.

  10. Turing patterns and apparent competition in predator-prey food webs on networks

    CERN Document Server

    Fernandes, Lucas D

    2012-01-01

    Reaction-diffusion systems may lead to the formation of steady state heterogeneous spatial patterns, known as Turing patterns. Their mathematical formulation is important for the study of pattern formation in general and play central roles in many fields of biology, such as ecology and morphogenesis. In the present study we focus on the role of Turing patterns in describing the abundance distribution of predator and prey species distributed in patches in a scale free network structure. We extend the original model proposed by Nakao and Mikhailov by considering food chains with several interacting pairs of preys and predators. We identify patterns of species distribution displaying high degrees of apparent competition driven by Turing instabilities. Our results provide further indication that differences in abundance distribution among patches may be, at least in part, due to self organized Turing patterns, and not necessarily to intrinsic environmental heterogeneity.

  11. The Apparent Lack of Lorentz Invariance in Zero-Point Fields with Truncated Spectra

    Directory of Open Access Journals (Sweden)

    Daywitt W. C.

    2009-01-01

    Full Text Available The integrals that describe the expectation values of the zero-point quantum-field-theoretic vacuum state are semi-infinite, as are the integrals for the stochastic electrodynamic vacuum. The unbounded upper limit to these integrals leads in turn to infinite energy densities and renormalization masses. A number of models have been put forward to truncate the integrals so that these densities and masses are finite. Unfortunately the truncation apparently destroys the Lorentz invariance of the integrals. This note argues that the integrals are naturally truncated by the graininess of the negative-energy Planck vacuum state from which the zero-point vacuum arises, and are thus automatically Lorentz invariant.

  12. Distribution of Aspergillus species among apparently healthy birds in poultry farms in Kaduna state, Nigeria

    Directory of Open Access Journals (Sweden)

    Clara N Kwanashie

    2013-03-01

    Full Text Available The study wasconducted to determine the prevalence and distribution of Aspergilllus species among apparently healthy birds in poultryfarms. Trachea swabs from 1500 birds in 52 commercial (10% of birds in eachpoultry farm visited poultry farms were collected for this study. Six speciesof Aspergillus were isolated wasisolated from 718 (47.87% of the birds viz: A. fumigatus made up 52.37% (376 of the Aspergillus isolates followed by A. flavus 21.87% (157, A.niger 11.42% (82, A. terreus8.64% (62, A. restrictus 2.79% (20and A. ochraceous 2.92% (21. Aspergillus species was found to occurthroughout the year in the farms though with a higher incidence during therainy season compared to the dry season.

  13. Apparent competition through facilitation between Melanoides tuberculata and Biomphalaria glabrata and the control of schistosomiasis

    Directory of Open Access Journals (Sweden)

    Giovanelli Alexandre

    2003-01-01

    Full Text Available Interactions between two species that result in reduced growth rates for both and extinction of one of the species are generally considered cases of asymmetric interspecific competition. Exploitative or interference competition is the usual mechanism invoked. Here we describe another mechanism producing the same result, named apparent competition through facilitation (ACF, observed between Melanoides tuberculata and Biomphalaria glabrata populations. The superior competitor actually gives some benefit to the other species, whose population becomes unstable with progressively increasing oscillations, leading to extinction. A model of ACF using difference equations suggests initial dynamics distinct from traditional interspecific competition. The dynamics of two freshwater snails in the field and in laboratory experiments suggest ACF, and these relations should be considered in studies of schistosomiasis control. ACF could occur in natural populations, but might have gone undetected because the final result is similar to traditional interspecific competition.

  14. STUDY OF ANEMIA IN APPARENTLY HEALTHY CHILDREN AGED 6 TO 15 MONTHS

    Directory of Open Access Journals (Sweden)

    Fysal

    2013-12-01

    Full Text Available Anemia due to lack of iron is the most important hematological disorder of infancy and childhood. According to India’s third National Family Health Survey ( NFHS - 3 of 2005 - 6 , 70 % of children between 6 months and 59 months are anemic. So it is very important to screen children for anemia early. The first 2 years of life is a critical window of opportunity to intervene in children since anemia can impair psychomotor development. A cross sectional study involving 260 apparently healthy children between 6 months and 15 months of age , showed the prevalence of anemia to be 60.7%. Only 9.2% of them were having Protein Energy Malnutrition. Introduction of animal milk at an early age and the amount of animal milk consumed were found to be the two important risk factors significantly associated with anemia. KEY WORDS: Hemoglobin , Protein Energy Malnutrition ( PEM , Microcytic Hypochromic Anemia , Exclusive Breast Feeding ( EBF

  15. Apparently non-invariant terms of nonlinear sigma models in lattice perturbation theory

    CERN Document Server

    Harada, Koji; Kubo, Hirofumi; Yamamoto, Yuki

    2009-01-01

    Apparently non-invariant terms (ANTs) which appear in loop diagrams for nonlinear sigma models (NLSs) are revisited in lattice perturbation theory. The calculations have been done mostly with dimensional regularization so far. In order to establish that the existence of ANTs is independent of the regularization scheme, and of the potential ambiguities in the definition of the Jacobian of the change of integration variables from group elements to "pion" fields, we employ lattice regularization, in which everything (including the Jacobian) is well-defined. We show explicitly that lattice perturbation theory produces ANTs in the four-point functions of the "pion" fields at one-loop and the Jacobian does not play an important role in generating ANTs.

  16. Variation of apparent mechanical anisotropy of cold-formed embossed sheet by annealing

    Science.gov (United States)

    Liu, Wuyang; Iizuka, Takashi

    2016-10-01

    Recently, with the demand of car lightweight, more and more high rigidity and formability material are required. So in order to achieve the lightweight, a good method is essential. [1] Although the thin sheet metal has light weight, the performance is changed to be lower with the sheet metal become thinner. In generally, the sheet metal has an anisotropy which depends on the aggregate structure. It have been investigated that by the embossing process the sheet metal is given new properties and the anisotropy. It's also investigated that the embossing process can improve the formability of the sheet metal. In this study, we used aluminum embossed sheet, and annealed the embossed sheet with different temperature. From the result, the variations of apparent mechanical properties of the embossed sheet by tensile test is confirmed. Furthermore, because annealing process can remove the work hardening, anisotropy derived from the embossing sub-macro structure was more obviously investigated.

  17. Dr Brasilia and Mr. Nacala: the apparent duality behind the Brazilian state-capital nexus

    Directory of Open Access Journals (Sweden)

    TOMASO FERRANDO

    2015-06-01

    Full Text Available In August 2010 Brazil decided to limit foreign direct investments (FDIs in land, and attracted the attention of politicians as much as the fears of businessmen. However, few months before, in September 2009, it had concluded a trilateral agreement with Japan and Mozambique to implement agribusiness and contract farming on an area of ten million hectares in the Mozambican region of Nacala. In light of that, the paper analyses the apparent duality of the Brazilian politics, and concludes that, exactly like in the case of the novel by Robert Louis Stevenson, it is not a matter of pathology, but a voluntarily induced double personality which is strategic in positioning Brazil at the core of the global capitalist system.

  18. Apparent horizons of an N-black-hole system in a space-time with a cosmological constant

    OpenAIRE

    Nakao, Ken-ichi; Yamamoto, Kazuhiro; Maeda, Kei-ichi

    1993-01-01

    We present the analytic solution of N Einstein-Rosen bridges ("N black holes") in the space-time with a cosmological constant Λ and analyze it for one- and two-bridge systems. We discuss the three kinds of apparent horizons: i.e., the black-hole, white-hole, and cosmological apparent horizons. In the case of two Einstein-Rosen bridges, when the "total mass" is larger than a critical value, the black-hole apparent horizon surrounding two Einstein-Rosen bridges is not formed even if the distanc...

  19. Corresponding Relation Between the Space-time Evolution of Seismic Apparent Strain and the Region of Strong Earthquakes in Yunnan

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    On the basis of our predecessors' research, we study the distribution and the space-time evolution characteristics of the seismic apparent strain field in Yunnan since the 1970's using the seismic data of Yunnan and its surrounding areas. The result shows that there is arather strong corresponding relationship between the anomaly region of seismic apparent strain and strong earthquakes. In the nine earthquakes studied, anomaly areas of seismic apparent strain had appeared before eight earthquakes, including five occurring in the anomaly region and three on the edge. Finally, the investigative result is demonstrated primarily.

  20. Visual Benefits in Apparent Motion Displays: Automatically Driven Spatial and Temporal Anticipation Are Partially Dissociated.

    Directory of Open Access Journals (Sweden)

    Merle-Marie Ahrens

    Full Text Available Many behaviourally relevant sensory events such as motion stimuli and speech have an intrinsic spatio-temporal structure. This will engage intentional and most likely unintentional (automatic prediction mechanisms enhancing the perception of upcoming stimuli in the event stream. Here we sought to probe the anticipatory processes that are automatically driven by rhythmic input streams in terms of their spatial and temporal components. To this end, we employed an apparent visual motion paradigm testing the effects of pre-target motion on lateralized visual target discrimination. The motion stimuli either moved towards or away from peripheral target positions (valid vs. invalid spatial motion cueing at a rhythmic or arrhythmic pace (valid vs. invalid temporal motion cueing. Crucially, we emphasized automatic motion-induced anticipatory processes by rendering the motion stimuli non-predictive of upcoming target position (by design and task-irrelevant (by instruction, and by creating instead endogenous (orthogonal expectations using symbolic cueing. Our data revealed that the apparent motion cues automatically engaged both spatial and temporal anticipatory processes, but that these processes were dissociated. We further found evidence for lateralisation of anticipatory temporal but not spatial processes. This indicates that distinct mechanisms may drive automatic spatial and temporal extrapolation of upcoming events from rhythmic event streams. This contrasts with previous findings that instead suggest an interaction between spatial and temporal attention processes when endogenously driven. Our results further highlight the need for isolating intentional from unintentional processes for better understanding the various anticipatory mechanisms engaged in processing behaviourally relevant stimuli with predictable spatio-temporal structure such as motion and speech.

  1. Elastic network models capture the motions apparent within ensembles of RNA structures.

    Science.gov (United States)

    Zimmermann, Michael T; Jernigan, Robert L

    2014-06-01

    The role of structure and dynamics in mechanisms for RNA becomes increasingly important. Computational approaches using simple dynamics models have been successful at predicting the motions of proteins and are often applied to ribonucleo-protein complexes but have not been thoroughly tested for well-packed nucleic acid structures. In order to characterize a true set of motions, we investigate the apparent motions from 16 ensembles of experimentally determined RNA structures. These indicate a relatively limited set of motions that are captured by a small set of principal components (PCs). These limited motions closely resemble the motions computed from low frequency normal modes from elastic network models (ENMs), either at atomic or coarse-grained resolution. Various ENM model types, parameters, and structure representations are tested here against the experimental RNA structural ensembles, exposing differences between models for proteins and for folded RNAs. Differences in performance are seen, depending on the structure alignment algorithm used to generate PCs, modulating the apparent utility of ENMs but not significantly impacting their ability to generate functional motions. The loss of dynamical information upon coarse-graining is somewhat larger for RNAs than for globular proteins, indicating, perhaps, the lower cooperativity of the less densely packed RNA. However, the RNA structures show less sensitivity to the elastic network model parameters than do proteins. These findings further demonstrate the utility of ENMs and the appropriateness of their application to well-packed RNA-only structures, justifying their use for studying the dynamics of ribonucleo-proteins, such as the ribosome and regulatory RNAs.

  2. Apparent Formation Factor for Leachate-Saturated Waste and Sediments: Examples from the USA and China

    Institute of Scientific and Technical Information of China (English)

    Philip J Carpenter; Ding Aizhong; Cheng Lirong; Liu Puxin; Chu Fulu

    2009-01-01

    The formation factor relates bulk resistivity to pore fluid resistivity in porous materials. Understanding the formation factor is essential in using electrical and electromagnetic methods to monitor leachate accumulations and movements both within and around landfills. Specifically, the formation factor allows leachate resistivity, the degree of saturation, and, possibly, even the hydraulic conductivity of the waste to be estimated from non-invasive surface measurements. In this study, apparent formation factors are computed for three landfills with different types of waste as well as sediments contaminated by landfill leachate. Resistivity soundings at the closed Mallard North landfill in suburban Chicago (Illinois, USA) mapped leachate surfaces that were confirmed by monitoring wells. The resistivity of leachate-saturated waste from resistivity sounding inversions was then divided by the leachate resistivity values measured in-situ to compute apparent formation factors (Fa) ranging from 1.6 to 4.9. A global Fa of 3.0±1.9 was computed for the entire monitored portion of this landfill At a nearby mixed laboratory waste landfill, a 2D inverted resistivity section was used to compute an Fa of 2.9. Finally, a distinctly different Fa value of 10.6±2.8 was computed for leachate-saturated retorted oil and organic compounds. The Fa for aquifers containing contaminated groundwater fall in the same range as aquifers with normal groundwater, 1.7-3.9. However, models from inverted sounding curves over these contaminated areas exhibit unusually low resistivity layers, which may be diagnostic of contamination.

  3. Occurrence of haemolytic Mannheimia spp. in apparently healthy sheep in Norway

    Directory of Open Access Journals (Sweden)

    Poulsen Louise L

    2006-10-01

    Full Text Available Abstract Background The occurrence of Mannheimia species in healthy sheep has only been investigated to a very limited extend since the genus and its five named species were established. The aim of the present study was to evaluate the occurrence of haemolytic Mannheimia species in apparently healthy sheep originating from four sheep flocks in South-Western Norway. Methods Typical β-haemolytic Pasteurellaceae were isolated from nasal swabs and subsequently subjected to bacteriological examination. A total of 57 Mannheimia isolates were obtained in pure culture. All isolates were genotyped by amplified fragment length polymorphisms (AFLP analysis and compared to six reference strains. The 16S rRNA gene sequences of two isolates were also determined. Results β-haemolytic Mannheimia species were isolated from 24% to 64% of the sheep in the four flocks. A total of 26 haemolytic M. ruminalis-like strains were isolated among which, a considerable genetic diversity was found. Eighteen M. glucosida isolates were obtained from three flocks, whereas M. haemolytica was only isolated from two flocks, 16 of them being from only one of the flocks. Conclusion We demonstrate that a relatively high number of apparently healthy sheep in Norway seem to carry the potentially pathogenic M. haemolytica and M. glucosida in the upper respiratory tract. An unexpectedly high number of haemolytic M. ruminalis-like organisms were also obtained in all four flocks. The usually non-haemolytic M. ruminalis are typically isolated from healthy ruminants. The significance of β-haemolytic M. ruminalis-like organisms is unknown and should be investigated in a future study.

  4. Concurrent temporal stability of the apparent electrical conductivity and soil water content

    Science.gov (United States)

    Pedrera-Parrilla, Aura; Pachepsky, Yakov A.; Taguas, Encarnación V.; Martos-Rosillo, Sergio; Giráldez, Juan V.; Vanderlinden, Karl

    2017-01-01

    Knowledge of spatio-temporal soil-water content (SWC) variability in agricultural fields is useful for improving crop management. Spatial patterns of SWC can be characterized using temporal stability analysis of difficult-to-obtain data from high spatial density and temporal frequency. Soil apparent electrical conductivity (ECa) measurements with high spatial density have been widely used to infer the spatial variability of SWC. The objective of this work is to test the hypothesis that temporal stability of ECa can be demonstrated and that relationships between temporal stability characteristics of SWC and ECa can be established. Apparent electrical conductivity and topsoil gravimetric SWC (θ) were periodically measured in an olive orchard in southwest Spain on 6 and 18 occasions, respectively. A temporal stability analysis of ECa elucidated three zones where ECa was close to, consistently substantially smaller than, and substantially larger than the spatial average ECa throughout the study period. Representative locations for θ were found with a chance of 75% within the representative zone for ECa. Yet, the driest locations, with consistently smaller θ than the field average (), could be successfully identified (89%) within the zone with consistently smaller ECa than average. The θ - relations showed generally a linear behaviour, although a better fit was obtained at the highest θ using either exponential or power law equations at half of the locations. The former provided the best fit within the zone with ECa consistently smaller than average, while the latter performed best in the zone with ECa consistently larger than average. The linear equation provided the best fit within the representative ECa zone. This study demonstrates that temporal stability characteristics of ECa and SWC are linked and that ECa surveys can be used to delimit zones with representative locations for SWC measurement or estimation. Such information is of importance for a range of

  5. Late bone metastasis from an apparently benign oncocytic follicular thyroid tumor

    Science.gov (United States)

    Boronat, Mauro; Cabrera, Juan J; Perera, Carmen; Isla, Concepción; Nóvoa, Francisco J

    2013-01-01

    A man underwent total thyroidectomy for goiter when he was 62 years old. The pathology report informed on a 5.5 cm oncocytic follicular adenoma and a 3.5 mm papillary microcarcinoma. Due to the papillary tumor, he was treated with ablative radioiodine therapy and suppressive doses of levothyroxine. After uneventful follow-up for 9 years, increased levels of serum thyroglobulin were detected. Further imaging studies including a whole body scan (WBS) after an empirical dose of 200 mCi 131I were negative. Two years later, a 99mTc SestaMIBI WBS and a 2-[18F]-fluoro-2-deoxy-d-glucose positron-emission tomography showed a well-delimited focal uptake in the right femur. A bone biopsy of the lesion demonstrated metastasis of follicular thyroid carcinoma. Retrospective histological reexamination of available material from the primary oncocytic thyroid tumor failed to reveal definitive traits of malignancy. Learning points Oncocytic follicular thyroid tumors are a relatively uncommon variant of follicular thyroid neoplasms mostly composed of distinctive large oxyphilic cells (Hürthle cells).Criteria for the distinction between benign and malignant oncocytic neoplasms are not different from those used in the diagnosis of ordinary follicular tumors.Some cases of apparently benign oncocytic neoplasms have been found to develop malignant behavior.Search to rule out vascular and capsular invasion should be particularly exhaustive in histological assessment of oncocytic thyroid tumors.Even so, long-term surveillance remains appropriate for patients with large apparently benign oncocytic tumors. PMID:24616777

  6. Protocol for determining Apparent Young's Modulus of human teeth using laser speckle interferometry

    Science.gov (United States)

    Salvador-Palmer, Rosario; González-Peña, Rolando J.; Martínez-Celorio, René A.; López, Francisco J.; Paredes, Vanessa; Cibrián, Rosa

    2012-10-01

    Digital Speckle Shearing Pattern Interferometry (DSSPI) allows to directly quantify deformations in teeth that are subjected to stress. Eighteen second premolars (2PM) were studied both before and after endodontic treatment made with the ProTaper method in order to evaluate the variation of dental elasticity. We present a protocol for determination tooth Apparent Young's Modulus (AYM). Each tooth underwent different flexion loads from 50 to 300 g. DSSPI technique, makes it possible to show the deformation at each point of a line, selected by the researcher, that goes from the attachment point (Point 0) to the root area where the load is applied (Point 300-350, depending on the tooth size). The deformation of each tooth was characterized by the deformation value of point 150, located around the mid-area of tooth. This value was obtained from a linear regression applied on the deformation values of all the points in the fitted line. The correlation coefficients of these fitted regression lines were always higher than 0.972. The elasticity constant of each tooth was obtained as the slope of a new regression line, corresponding to the different loads applied on the tooth versus the corresponding deformation at point 150. This value, divided by the length of the tooth, is the apparent Young's modulus (AYM), which is expressed in arbitrary units (a.u.). Values of the AYM before (4.16 104 a.u) and after endodontic treatment using the ProTaper method (4.30 104 a.u.) showed no statistically significant difference in the elasticity of teeth (p>0.7).

  7. The IGS-combined station coordinates, earth rotation parameters and apparent geocenter

    Science.gov (United States)

    Ferland, R.; Piraszewski, M.

    2009-03-01

    The International GNSS Service (IGS) routinely generates a number of weekly, daily and sub-daily products. Station coordinates and velocities, earth rotation parameters (ERPs) and apparent geocenter are among these products generated weekly by the IGS Reference Frame Coordinator. They have been determined since 1999 by combining independent estimates from at least seven IGS Analysis Centers (ACs). Two Global Network Associate Analysis Centers (GNAACs) also provide independent combinations using the same AC weekly solutions and they are currently used to quality control the IGS combination. The combined solutions are aligned to an IGS realization (IGS05) of the ITRF2005 using a carefully selected set of the IGS Reference Frame (RF) stations (nominally 132). During the combination process, the contributing solutions are compared and outliers are removed to ensure a high level of consistency of the estimated parameters. The ACs and the weekly combined solution are consistent at the 1-2 and 3-4 mm levels for the horizontal and vertical components. Similarly, the excess Length of Day (LOD), the pole positions and pole rates are consistent at the 10μs, 0.03-0.05 mas and 0.10-0.20 mas/day levels, respectively. The consistency of the apparent geocenter estimate is about 5 mm in the X and Y components and 10 mm in the Z component. Comparison of the IGS-combined ERP estimates with the IERS Bulletin A suggests a small bias of the order of -0.04 mas and + 0.05 mas (both ±0.05 mas) in the x and y components.

  8. Introduction to the Volume.

    Science.gov (United States)

    Emihovich, Catherine; Schroder, Barbara; Panofsky, Carolyn P.

    1999-01-01

    Introduces a volume that examines the issue of critical thinking and whether or not it is culturally specific, discussing recent research on the subject. The papers focus on critical thinking and culture, historical consciousness and critical thinking, critical thinking as cultural-historical practice, culture and the development of critical…

  9. Detection of Flux Emergence, Splitting, Merging, and Cancellation of Network Fields. II Apparent Unipolar Flux Change and Cancellation

    CERN Document Server

    Iida, Y; Yokoyama, T

    2015-01-01

    In this second paper in the series, we investigate occurrence frequencies of apparent unipolar processes, cancellation, and emergence of patch structures in quiet regions. Apparent unipolar events are considerably more frequent than cancellation and emergence as per our definition, which is consistent with Lamb et al. (2013). Furthermore, we investigate the frequency distributions of changes in flux during apparent unipolar processes are and found that they concentrate around the detection limit of the analysis. Combining these findings with the results of our previous paper, Iida et al. (2012), that merging and splitting are more dominant than emergence and cancellation, these results support the understanding that apparent unipolar processes are actually interactions with and among patches below the detection limit and that there still are numerous flux interactions between the flux range in this analysis and below the detection limit. We also investigate occurrence frequency distributions of flux decrease ...

  10. The Effect of the Operating Conditions on the Apparent Viscosity of Crude Palm Oil During Oil Clarification

    Directory of Open Access Journals (Sweden)

    Sulaiman Al-Zuhair, Mirghani I. Ahmed and Yousif A. Abakr

    2012-10-01

    Full Text Available This paper discusses the apparent viscosity of crude palm oil, using rotary viscometer, under different boundary conditions. It was experimentally shown that the apparent viscosity of palm oil drops with increasing of the shear rate and the temperature.  However, the effect of temperature on the viscosity tends to fade at temperatures beyond 80 oC.  A correlation between the apparent viscosity of crude palm oil and the operating conditions was developed. This correlation can be used in design of crude palm oil settlers and in determining the optimum operating conditions.Key Words:  Crude palm oil, apparent viscosity, shear rate, modelling, separation 

  11. Can Apparent Stress be Used to Time-Dependent Seismic Hazard Assessment or Earthquake Forecast? An Ongoing Approach in China

    Science.gov (United States)

    Wu, Zhongliang; Jiang, Changsheng; Zhang, Shengfeng

    2016-08-01

    The approach in China since the last 1.5 decade for using apparent stress in time-dependent seismic hazard assessment or earthquake forecast is summarized. Retrospective case studies observe that apparent stress exhibits short-term increase, with time scale of several months, before moderate to strong earthquakes in a large area surrounding the `target earthquake'. Apparent stress is also used to estimate the tendency of aftershock activity. The concept relating apparent stress indirectly to stress level is used to understand the properties of some `precursory' anomalies. Meanwhile, different opinions were reported. Problems in the calculation also existed for some cases. Moreover, retrospective studies have the limitation in their significance as compared to forward forecast test. Nevertheless, this approach, seemingly uniquely carried out in a large scale in mainland China, provides the earthquake catalogs for the predictive analysis of seismicity with an additional degree of freedom, deserving a systematic review and reflection.

  12. The incidence of apparent congenital urogenital anomalies in North Indian newborns: A study of 20,432 pregnancies

    Directory of Open Access Journals (Sweden)

    A. Bhat

    2016-09-01

    Conclusions: The incidence of apparent congenital urogenital anomalies was 3.91%. Infertility treatment, parity >2 and a maternal age >30 years were independently associated with an increased risk of congenital urogenital anomalies.

  13. IAU 2015 Resolution B2 on Recommended Zero Points for the Absolute and Apparent Bolometric Magnitude Scales

    OpenAIRE

    Mamajek, E. E.; Torres, G.; Prsa, A.; Harmanec, P.; Asplund, M.; Bennett, P. D.; Capitaine, N.; Christensen-Dalsgaard, J.; Depagne, E.; Folkner, W. M.; Haberreiter, M.; Hekker, S.; Hilton, J. L.; Kostov, V.; Kurtz, D. W.

    2015-01-01

    The XXIXth IAU General Assembly in Honolulu adopted IAU 2015 Resolution B2 on recommended zero points for the absolute and apparent bolometric magnitude scales. The resolution was proposed by the IAU Inter-Division A-G Working Group on Nominal Units for Stellar and Planetary Astronomy after consulting with a broad spectrum of researchers from the astronomical community. Resolution B2 resolves the long-standing absence of an internationally-adopted zero point for the absolute and apparent bolo...

  14. 3D imaging of soil apparent electrical conductivity from VERIS data using a 1D spatially constrained inversion algorithm

    Science.gov (United States)

    Jesús Moral García, Francisco; Rebollo Castillo, Francisco Javier; Monteiro Santos, Fernando

    2016-04-01

    Maps of apparent electrical conductivity of the soil are commonly used in precision agriculture to indirectly characterize some important properties like salinity, water, and clay content. Traditionally, these studies are made through an empirical relationship between apparent electrical conductivity and properties measured in soil samples collected at a few locations in the experimental area and at a few selected depths. Recently, some authors have used not the apparent conductivity values but the soil bulk conductivity (in 2D or 3D) calculated from measured apparent electrical conductivity through the application of an inversion method. All the published works used data collected with electromagnetic (EM) instruments. We present a new software to invert the apparent electrical conductivity data collected with VERIS 3100 and 3150 (or the more recent version with three pairs of electrodes) using the 1D spatially constrained inversion method (1D SCI). The software allows the calculation of the distribution of the bulk electrical conductivity in the survey area till a depth of 1 m. The algorithm is applied to experimental data and correlations with clay and water content have been established using soil samples collected at some boreholes. Keywords: Digital soil mapping; inversion modelling; VERIS; soil apparent electrical conductivity.

  15. Apparent Consumption vs. Total Consumption--A Lead-Acid Battery Case Study

    Science.gov (United States)

    Wilburn, David R.; Buckingham, David A.

    2006-01-01

    Introduction: This report compares estimates of U.S. apparent consumption of lead with estimates of total U.S. consumption of this mineral commodity from a materials flow perspective. The difference, attributed to the amount of lead contained in imported and exported products, was found to be significant for this sector. The study also assesses the effects of including mineral commodities incorporated in manufactured products on the interpretation of observed trends in minerals consumption and trade. Materials flow is a systems approach to understanding what happens to the materials we use from the time a material is extracted, through its processing and manufacturing, to its ultimate disposition. The U.S. Geological Survey (USGS) provides accurate and detailed mineral production and mineral commodity consumption statistics that are essential for government, nongovernment organizations, and the public to gain a better understanding of how and where materials are used and their effect on the environment and society. Published statistics on mineral apparent consumption are limited to estimates of consumption of raw material forms (ore, concentrate, and [or] refined metal). For this study, apparent consumption is defined as mine production + secondary refined production + imports (concentrates and refined metal) ? exports (concentrates and refined metal) + adjustments for government and industry stock changes. These estimates do not account for the amount of mineral commodities contained in manufactured products that are imported to the United States, nor do they deduct the amount of these mineral commodities contained in manufactured products that are exported from the United States. When imports or exports of manufactured products contribute significantly to the total use of a particular raw material, an estimate of consumption that does not consider the incorporated forms of these mineral commodities within imported or exported manufactured products can be either

  16. Postoperative volume balance

    DEFF Research Database (Denmark)

    Frost, H; Mortensen, C.R.; Secher, N H;

    2016-01-01

    In healthy humans, stroke volume (SV) and cardiac output (CO) do not increase with expansion of the central blood volume by head-down tilt or administration of fluid. Here, we exposed 85 patients to Trendelenburg's position about one hour after surgery while cardiovascular variables were determined...... non-invasively by Modelflow. In Trendelenburg's position, SV (83 ± 19 versus 89 ± 20 ml) and CO (6·2 ± 1·8 versus 6·8 ± 1·8 l/min; both P... (39%) with a > 10% increase in SV (from 78 ± 16 to 90 ± 17 ml) corresponding to an increase in CO from 5·9 ± 1·5 to 6·9 ± 1·6 l min(-1) (Phead-down, administration of 250 ml Ringer's lactate solution increased SV (to 88 ± 18 ml) and CO (to 6·8 ± 1·7 l min(-1) ). In conclusion...

  17. Apparent stress, fault maturity and seismic hazard for normal-fault earthquakes at subduction zones

    Science.gov (United States)

    Choy, G.L.; Kirby, S.H.

    2004-01-01

    The behavior of apparent stress for normal-fault earthquakes at subduction zones is derived by examining the apparent stress (?? a = ??Es/Mo, where E s is radiated energy and Mo is seismic moment) of all globally distributed shallow (depth, ?? 1 MPa) are also generally intraslab, but occur where the lithosphere has just begun subduction beneath the overriding plate. They usually occur in cold slabs near trenches where the direction of plate motion across the trench is oblique to the trench axis, or where there are local contortions or geometrical complexities of the plate boundary. Lower ??a (tectonic regime suggests that the level of ?? a is related to fault maturity. Lower stress drops are needed to rupture mature faults such as those found at plate interfaces that have been smoothed by large cumulative displacements (from hundreds to thousands of kilometres). In contrast, immature faults, such as those on which intraslab-normal-fault earthquakes generally occur, are found in cold and intact lithosphere in which total fault displacement has been much less (from hundreds of metres to a few kilometres). Also, faults on which high ??a oceanic strike-slip earthquakes occur are predominantly intraplate or at evolving ends of transforms. At subduction zones, earthquakes occurring on immature faults are likely to be more hazardous as they tend to generate higher amounts of radiated energy per unit of moment than earthquakes occurring on mature faults. We have identified earthquake pairs in which an interplate-thrust and an intraslab-normal earthquake occurred remarkably close in space and time. The intraslab-normal member of each pair radiated anomalously high amounts of energy compared to its thrust-fault counterpart. These intraslab earthquakes probably ruptured intact slab mantle and are dramatic examples in which Mc (an energy magnitude) is shown to be a far better estimate of the potential for earthquake damage than Mw. This discovery may help explain why loss of

  18. Variability in apparent soil organic carbon turnover times across climate zones and vegetation classes

    Science.gov (United States)

    Khomik, M.; Reichstein, M.; Schrumpf, M.; Beer, C.; Curiel Yuste, J.; Janssens, I.; Luyssaert, S.; Subke, J.; Trumbore, S.; Wutzler, T.; Fluxnet Lathuile: Www. Fluxdata. Org

    2011-12-01

    Our understanding about the climatic controls on the rate of soil organic carbon (SOC) decomposition is still limited and greatly debated, especially the temperature sensitivity of SOC decomposition. Some argue that SOC turnover time (TO) decreases exponentially with increasing temperatures, while others disagree. Based on a number of assumptions, we calculated the ratio between soil CO2 efflux and soil bulk carbon stocks, from which we obtained an estimate of apparent TO for bulk soils across a selection of forested sites around the globe. We used data collected from site-PIs and from recently-available databases of: soil chamber flux measurements (Global soil respiration database: code.google.com/p/srdb/), ecosystem carbon flux measurements (FLUXNET LaThuile dataset: www.fluxdata.org), and global soil carbon stock estimates (Harmonized world soil database: www.iiasa.ac.at/Research/LUC/External-World-soil-database/HTML/). We investigated across-site variability of these apparent TO values in relation to climate (i.e. site's mean annual temperature, MAT, and total annual precipitation, TAP) and vegetation classes (i.e. broadleaf deciduous, needle-leaf deciduous, broadleaf evergreen, and needle-leaf evergreen). We found that, when all data points were considered, TO decreased exponentially with increasing MAT and TAP, in accordance with past studies, although the relationship with TAP was not as strong as with MAT. The overall negative exponential relationship was maintained even when the data was analyzed under the combined effects of MAT and TAP and vegetation class. TO at sites with low annual precipitation and low mean annual temperatures were high (i.e. the rate of decomposition was low). However, we also found that this overall global exponential relationship was largely driven by the difference in TO between sites located in the boreal climate zone and sites located in the other climate zones considered (i.e. tropical, Mediterranean and temperate climate

  19. Apparent diffusion coefficient and fractional anisotropy of newly diagnosed grade II gliomas†

    Science.gov (United States)

    Khayal, Inas S.; McKnight, Tracy R.; McGue, Colleen; Vandenberg, Scott; Lamborn, Kathleen R.; Chang, Susan M.; Cha, Soonmee; Nelson, Sarah J.

    2013-01-01

    Distinguishing between low-grade oligodendrogliomas (ODs) and astrocytomas (AC) is of interest for defining prognosis and stratifying patients to specific treatment regimens. The purpose of this study was to determine if the apparent diffusion coefficient (ADC) and fractional anisotropy (FA) from diffusion imaging can help to differentiate between newly diagnosed grade II OD and AC subtypes and to evaluate the ADC and FA values for the mixed population of oligoastrocytomas (OA). Fifty-three patients with newly diagnosed grade II gliomas were studied using a 1.5T whole body scanner (23 ODs, 16 ACs, and 14 OAs). The imaging protocol included post-gadolinium T1-weighted images, T2-weighted images, and either three and/or six directional diffusion imaging sequence with b = 1000 s/mm2. Diffusion-weighted images were analyzed using in-house software to calculate maps of ADC and for six directional acquisitions, FA. The intensity values were normalized by values from normal appearing white matter (NAWM) to generate maps of normalized apparent diffusion coefficient (nADC) and normalized fractional anisotropy (nFA). The hyperintense region in the T2 weighted image was defined as the T2All region. A Mann–Whitney rank-sum test was performed on the 25th, median, and 75th nADC and nFA among the three subtypes. Logistic regression was performed to determine how well the nADC and nFA predict subtype. Lesions diagnosed as being OD had significantly lower nADC and significantly higher nFA, compared to AC. The nADC and nFA values individually classified the data with an accuracy of 87%. Combining the two did not enhance the classification. The patients with OA had nADC and nFA values between those of OD and AC. This suggests that ADC and FA may be helpful in directing tissue sampling to the most appropriate regions for taking biopsies in order to make a definitive diagnosis. PMID:19125391

  20. Corps, apparences vestimentaires et identités en France à la Renaissance

    Directory of Open Access Journals (Sweden)

    Isabelle Paresys

    2012-02-01

    Full Text Available Un corps vêtu spécifique émerge à la Renaissance en France et particulièrement à la Cour. Le vêtement impose sa marque sur le corps, accentue le dimorphisme sexuel des apparences, et donne à celles-ci rectitude ou distorsion, transformant le corps en une surface décorative sur laquelle peut s’exprimer la magnificence des souverains et celle de leur cour. Ce corps vêtu résulte de l’influence de modes européennes et de nouvelles normes de civilité qui construisent la présentation de soi. Elles trouvent leur pleine expression à la cour où le corps de mode aristocratique affiche une éloquence distinctive et cosmopolite. Dans le même temps, les identités qu’inculque le vêtement au corps paraissent menacées par les transferts de pratiques vestimentaires entre les sexes, entre les groupes sociaux et entre les nations, entraînant un malaise envers ce brouillage des apparences qui prend une couleur particulière durant les guerres civiles quand se pose de manière sanglante la question des identités et de la conscience nationale.Body, Dress and Identities in Renaissance France. A specific type of clothed body emerged in 16th century France especially at Court. Clothing put its mark on the body, accentuating sexual dimorphism, imposing either Renaissance rectitude or distortions, transforming the body into a decorative surface for displaying magnificence. Its specificity resulted from the influence of various vestimentary and decorative fashions, starting with the new kinds of civility circulating in Renaissance Europe, which fashioned self-presentation. It found its fullest expression on the bodies of cosmopolitan aristocrats seeking a distinctive eloquence for their particular identity. At the same time, the identities which clothes imprinted on their wearer seemed threatened by transfers of vestimentary practices between sexes, sexual groups, and/or nations. The unease created by this mixture of appearances reflects that of

  1. Testing the apparent resistance of three dominant plants to chronic drought on the Colorado Plateau

    Science.gov (United States)

    Hoover, David L.; Duniway, Michael C.; Belnap, Jayne

    2016-01-01

    Many drylands, including the south-western United States, are projected to become more water-limited as these regions become warmer and drier with climate change. Such chronic drought may push individual species or plant functional types beyond key thresholds leading to reduced growth or even mortality. Indeed, recent observational and experimental evidence from the Colorado Plateau suggests that C3 grasses are the most vulnerable to chronic drought, while C4 grasses and C3 shrubs appear to have greater resistance.The effects of chronic, or press-drought are predicted to begin at the physiological level and translate up to higher hierarchical levels. To date, the drought resistance of C4grasses and C3 shrubs in this region has been only evaluated at the community level and thus we lack information on whether there are sensitivities to drought at lower hierarchical levels. In this study, we tested the apparent drought resistance of three dominant species (Pleuraphis jamesii, a C4 rhizomatous grass; Coleogyne ramosissima, a C3 drought-deciduous shrub; and Ephedra viridis, a C3 evergreen shrub) to an ongoing experimental press-drought (-35% precipitation) by comparing individual-level responses (ecophysiology and growth dynamics) to community-level responses (plant cover).For all three species, we observed consistent responses across all hierarchical levels:P. jamesii was sensitive to drought across all measured variables, while the shrubsC. ramosissima and E. viridis had little to no responses to the experimental press-drought at any given level.Synthesis. Our findings suggest that the apparent drought resistance at higher hierarchical levels, such as cover, may serve as good proxies for lower-level responses. Furthermore, it appears the shrubs are avoiding drought, possibly by utilizing moisture at deeper soil layers, while the grasses are limited to shallower layers and must endure the drought conditions. Give this differential sensitivity to drought, a future

  2. On the origin of apparent Z1-oscillations in low-energy heavy-ion ranges

    Science.gov (United States)

    Wittmaack, Klaus

    2016-12-01

    It has been known for quite some time that projected ranges measured by Rutherford backscattering spectrometry for a variety of low-energy heavy ions (energy-to-mass ratio E/M1 less than ∼0.4 keV/u) exhibit significant or even pronounced deviations from the theoretically predicted smooth dependence on the projectile's atomic number Z1. Studied most thoroughly for silicon targets, the effect was attributed to 'Z1 oscillations' in nuclear stopping, in false analogy to the well established Z1 oscillations in electronic stopping of low-velocity light ions. In this study an attempt was made to get order into range data published by four different groups. To achieve the goal, the absolute values of the ranges from each group had to be (re-)adjusted by up to about ±10%. Adequate justification for this approach is provided. With the changes made, similarities and differences between the different sets of data became much more transparent than before. Very important is the finding that the distortions in heavy-ion ranges are not oscillatory in nature but mostly one-sided, reflecting element-specific transport of implanted atoms deeper into the solid. Exceptions are rare gas and alkali elements, known to exhibit bombardment induced transport towards the surface. Range distortions reported for Xe and Cs could be reproduced on the basis of the recently established rapid relocation model. The extent of transport into the bulk, observed with many other elements, notably noble metals and lanthanides, reflects their high mobility under ion bombardment. The complexity of the element specific transport phenomena became fully evident by also examining the limited number of data available for the apparent range straggling. Profile broadening was identified in several cases. One element (Eu) was found to exhibit profile narrowing. This observation suggests that implanted atoms may agglomerate at peak concentrations up to 2%, possibly a tool for generating nano-structured dopant

  3. Select Papers. Volume 1

    Science.gov (United States)

    2011-08-01

    non- uniform rational B-splines (NURBS), 127 and BRL-CAD TM format. This dual-package development allowed for rapid development of components ...next generation of scientists and engineers. A fundamental component of our outreach program is to provide students research experiences at ARL...summer intern. There, I ran Volume Based Morphometry , an application of Statistical Parametric Mapping that was new to the Hirsch lab. I

  4. Use of steel slag as a granular material: volume expansion prediction and usability criteria.

    Science.gov (United States)

    Wang, George; Wang, Yuhong; Gao, Zhili

    2010-12-15

    The theoretical equation for predicting volume expansion of steel slag is deduced based on both chemical reaction and physical changes of free lime in steel slag during the hydration process. Laboratory volume expansion testing is conducted to compare the results with the theoretical volume expansion. It is proved that they correlated well. It is furthermore experimentally proved that certain volume expansion of steel slag can be absorbed internally by the void volume in bulk steel slag under external surcharge weight making the apparent volume expansion equal zero. The minimum (lowest) absorbable void volume is approximately 7.5%, which is unrelated to the free lime content. A usability criterion is then developed based on the volume expansion of steel slag (%) and the minimum percentage of the volume that can take the volume expansion of steel slag (%). Eventually the criterion (relationship) is established based on the free lime content, the specific gravity and bulk relative gravity of a specific steel slag sample. The criteria can be used as guidance and specification for the use of steel slag and other expansion-prone nonferrous slags, copper, nickel for instance as a granular material in highway construction.

  5. Apparent partial resetting of U-Th-Pb systems in experimentally altered monazite resulting from nano-mixtures due to incomplete replacement.

    Science.gov (United States)

    Grand'homme, Alexis; Janots, Emilie; Seydoux-Guillaume, Anne-Magali; Guillaume, Damien; Bosse, Valérie; Magnin, Valérie

    2016-04-01

    Hydrothermal alteration experiments of natural monazite crystals (Manangotry, Madagascar; 555 Ma) under alkali conditions (NaOH 1M in 18O doped solution) at low temperature conditions (300, 400, 500 and 600°C), 200 MPa, were conducted to clarify the origin of unsupported Pb (radiogenic or not) in altered monazite (Seydoux-Guillaume et al., 2012). At 300°C, no evidence of monazite replacement was observed. From 400 to 600°C, experimental products show a replacement texture with pristine monazite (Mnz1) surrounded by an alteration rim with a different composition (SEM and EPMA). In the altered domains, in-situ isotopic and chemical U-Th-Pb dating yields intermediate ages between original monazite (555 Ma) and complete experimental resetting (0 Ma). Incomplete resetting is due to the systematic presence of Pb in altered domains, whose concentration decreases with increasing temperature. Transmission Electron Microscope (TEM) observations reveal an incomplete replacement of Mnz1 by a secondary monazite (Mnz2), free of Pb, within the altered domain. The latter domain, apparently homogeneous in BSE images, is in fact constituted by closely associated nano-mixtures of Mnz1 and Mnz2. Furthermore, the volume of Mnz2 within the altered domain, i.e. the efficiency of replacement, increases with increasing temperature. Apparent partial resetting of U-Th-Pb systems results from the unavoidable nano-mixture of different proportion of Mnz1 and Mnz2 within the analytical microvolume (EPMA, LA-ICP-MS). This study therefore indicates that the micrometric resolution (even the 5 μm3 for EPMA) of in-situ dating techniques may be not sufficient to solve such nano-replacement domains, especially when alteration occurs at low-temperature. Ref: Seydoux-Guillaume, A.-M., Montel, J.-M., Bingen, B., Bosse, V., de Parseval, P., Paquette, J.-L., Janots, E., and Wirth, R., (2012). Chemical Geology, v. 330-331, p. 140-158.

  6. State-dependent decisions cause apparent violations of rationality in animal choice.

    Science.gov (United States)

    Schuck-Paim, Cynthia; Pompilio, Lorena; Kacelnik, Alex

    2004-12-01

    Normative models of choice in economics and biology usually expect preferences to be consistent across contexts, or "rational" in economic language. Following a large body of literature reporting economically irrational behaviour in humans, breaches of rationality by animals have also been recently described. If proven systematic, these findings would challenge long-standing biological approaches to behavioural theorising, and suggest that cognitive processes similar to those claimed to cause irrationality in humans can also hinder optimality approaches to modelling animal preferences. Critical differences between human and animal experiments have not, however, been sufficiently acknowledged. While humans can be instructed conceptually about the choice problem, animals need to be trained by repeated exposure to all contingencies. This exposure often leads to differences in state between treatments, hence changing choices while preserving rationality. We report experiments with European starlings demonstrating that apparent breaches of rationality can result from state-dependence. We show that adding an inferior alternative to a choice set (a "decoy") affects choices, an effect previously interpreted as indicating irrationality. However, these effects appear and disappear depending on whether state differences between choice contexts are present or not. These results open the possibility that some expressions of maladaptive behaviour are due to oversights in the migration of ideas between economics and biology, and suggest that key differences between human and nonhuman research must be recognised if ideas are to safely travel between these fields.

  7. Apparent Skin Discoloration about the Knee Joint: A Rare Sequela of Metallosis after Total Knee Replacement

    Directory of Open Access Journals (Sweden)

    Narlaka Jayasekera

    2015-01-01

    Full Text Available Introduction. Metallosis is a phenomenon most commonly associated with hip replacement. However it can occur in any metallic implant subject to wear. Wear creates metal debris, which is deposited in the surrounding soft tissue. This leads to many local adverse reactions including, but not limited to, implant loosening/osteolysis, pain, and effusion. In the deeper joints, for example, the hip, metal deposits are mostly only seen intraoperatively. Case Study. A 74-year-old lady represented to orthopaedic outpatient clinic. Her principle complaint was skin discolouration, associated with pain and swelling over the left knee, on the background of a previous total knee replacement with a metal backed patella resurfacing six years. A plain radiograph revealed loosening of the patellar prosthesis. A diagnosis of metallosis was made; the patient underwent debridement of the stained soft tissue and primary revision of the prosthesis. She remained symptom-free five years after revision. Discussion. Metallosis results in metallic debris which causes tissue staining, often hidden within the soft tissue envelope of the hip, but more apparent in the knee. Metallosis may cause pain, effusion, and systemic symptoms because of raised levels of serum-metal ions. Surgical intervention with revision and debridement can have good functional results.

  8. Apparent cure of a newborn with malignant osteopetrosis using prednisone therapy.

    Science.gov (United States)

    Iacobini, M; Migliaccio, S; Roggini, M; Taranta, A; Werner, B; Panero, A; Teti, A

    2001-12-01

    A newborn girl with hemorrhagic purpura, suspected neonatal sepsis, and pale and dry skin was lethargic with remarkable hepatosplenomegaly, convergent strabismus, severe anemia, and elevated alkaline phosphatase activity. Radiographs showed a generalized increase in bone density, small medullary cavities, sclerosis of the skull and vertebrae, transverse wavy stripes of sclerotic bone in the metaphyses, and bone-in-bone appearance in phalanges of hands and feet. On this basis, she was diagnosed with malignant infantile osteopetrosis. On the first day of life, the infant was given a blood transfusion and vitamin K (1 mg intravenously [iv]). Corticosteroid therapy was started with prednisone (2 mg/kg per day). She showed marked improvement of symptoms. On the 26th day and 42nd day of life, she received additional blood transfusions. On the 49th day, the patient was discharged and corticosteroid therapy was continued at a regimen of 5 mg/day. Subsequent blood sample analyses revealed normal values for age. At 1 year of life, a bone marrow sample showed normal white and red cell lineages. X-ray confirmed attenuation of the bone sclerosis; therefore, bone marrow transplantation (BMT) was not implemented. At the age of 1.5 years, prednisone therapy was discontinued gradually and withdrawn before the age of 2 years. Subsequent follow-up showed normalization of all radiological and hematologic parameters. At present, the patient is 3 years old and appears healthy with apparently complete regression of the disease.

  9. A statistical representation of the cosmological constant from finite size effects at the apparent horizon

    Science.gov (United States)

    Viaggiu, Stefano

    2016-07-01

    In this paper we present a statistical description of the cosmological constant in terms of massless bosons (gravitons). To this purpose, we use our recent results implying a non vanishing temperature {T_{Λ }} for the cosmological constant. In particular, we found that a non vanishing T_{Λ } allows us to depict the cosmological constant Λ as composed of elementary oscillations of massless bosons of energy hbar ω by means of the Bose-Einstein distribution. In this context, as happens for photons in a medium, the effective phase velocity v_g of these massless excitations is not given by the speed of light c but it is suppressed by a factor depending on the number of quanta present in the universe at the apparent horizon. We found interesting formulas relating the cosmological constant, the number of quanta N and the mean value overline{λ } of the wavelength of the gravitons. In this context, we study the possibility to look to the gravitons system so obtained as being very near to be a Bose-Einstein condensate. Finally, an attempt is done to write down the Friedmann flat equations in terms of N and overline{λ }.

  10. Mesquite pod meal in sheep diet: intake, apparent digestibility of nutrients and nitrogen balance

    Directory of Open Access Journals (Sweden)

    Edileusa de Jesus do Santos

    2015-02-01

    Full Text Available Eight Santa Ines sheep were assigned to two 4 x 4 Latin squares, to evaluate the effects of replacing elephant grass silage with different levels of mesquite pod meal (MDM (15, 30 and 45% DM on intake, apparent digestibility of dry matter (DM, organic matter (OM, crude protein (CP, ether extract (EE, acid detergent fiber (ADF, neutral detergent fiber (NDF, total carbohydrates (TC and non-fiber carbohydrates (NFC and the nitrogen balance. There was a linear increase (p < 0.05 in the intake of DM, OM, CP, ADF, NDF, NFC and TC according to the addition of MPM to the diet. The digestibility of DM, OM and CP increased (p < 0.05 with the addition of MDM. We observed a positive linear effect (p < 0.05 for the nitrogen intake. The addition of mesquite pod meal up to 45% increased the intake of DM, NDF, ADF, CP, OM, NFC and TC but reduced the digestibility of EE and NDF. MPM at 30 and 45% propitiated a positive nitrogen balance.

  11. Apparent temperature and cause-specific emergency hospital admissions in Greater Copenhagen, Denmark.

    Directory of Open Access Journals (Sweden)

    Janine Wichmann

    Full Text Available One of the key climate change factors, temperature, has potentially grave implications for human health. We report the first attempt to investigate the association between the daily 3-hour maximum apparent temperature (Tapp(max and respiratory (RD, cardiovascular (CVD, and cerebrovascular (CBD emergency hospital admissions in Copenhagen, controlling for air pollution. The study period covered 1 January 2002-31 December 2006, stratified in warm and cold periods. A case-crossover design was applied. Susceptibility (effect modification by age, sex, and socio-economic status was investigated. For an IQR (8°C increase in the 5-day cumulative average of Tapp(max, a 7% (95% CI: 1%, 13% increase in the RD admission rate was observed in the warm period whereas an inverse association was found with CVD (-8%, 95% CI: -13%, -4%, and none with CBD. There was no association between the 5-day cumulative average of Tapp(max during the cold period and any of the cause-specific admissions, except in some susceptible groups: a negative association for RD in the oldest age group and a positive association for CVD in men and the second highest SES group. In conclusion, an increase in Tapp(max is associated with a slight increase in RD and decrease in CVD admissions during the warmer months.

  12. Diversity and complexity complement apparent competition: Nematode assemblages in banana plantations

    Science.gov (United States)

    Ferris, Howard; Pocasangre, Luis E.; Serrano, Edgardo; Muñoz, Jorge; Garcia, Socorro; Perichi, Guillermo; Martinez, Gustavo

    2012-04-01

    The structure of communities of soil organisms, and, therefore, their ecosystem functions, respond to spatial and temporal changes in plant diversity and to subsidies of organic matter. We introduce the concept of amplifiable and target prey in directing the impact of shared predators on pest organisms. In soil nematode assemblages, rather than overt apparent competition between the two prey categories, the effects were more subtle and expressed as increased predation pressure on the target prey when resources for the amplifiable prey were greater. We conclude that the connectance complexity of the food web subverts resource flow through a sequential chain of trophic interactions so that interaction strength decreases at successive trophic exchange. However, the effect of resource diversion is that the net regulatory pressure on the target prey is potentially enhanced by the increase in alternate predators of each prey category. The system requires that certain criteria are met, including that predator populations are resource limited, that conditions are conducive for predator survival and increase, and that predators, amplifiable and target prey are co-located in a majority of patches associated with resource subsidy, favorable conditions or migration patterns.

  13. SIMSISH technique does not alter the apparent isotopic composition of bacterial cells.

    Directory of Open Access Journals (Sweden)

    Olivier Chapleur

    Full Text Available In order to identify the function of uncultured microorganisms in their environment, the SIMSISH method, combining in situ hybridization (ISH and nanoscale secondary ion mass spectrometry (nanoSIMS imaging, has been proposed to determine the quantitative uptake of specific labelled substrates by uncultured microbes at the single cell level. This technique requires the hybridization of rRNA targeted halogenated DNA probes on fixed and permeabilized microorganisms. Exogenous atoms are introduced into cells and endogenous atoms removed during the experimental procedures. Consequently differences between the original and the apparent isotopic composition of cells may occur. In the present study, the influence of the experimental procedures of SIMSISH on the isotopic composition of carbon in E. coli cells was evaluated with nanoSIMS and compared to elemental analyser-isotopic ratio mass spectrometer (EA-IRMS measurements. Our results show that fixation and hybridization have a very limited, reproducible and homogeneous influence on the isotopic composition of cells. Thereby, the SIMSISH procedure minimizes the contamination of the sample by exogenous atoms, thus providing a means to detect the phylogenetic identity and to measure precisely the carbon isotopic composition at the single cell level. This technique was successfully applied to a complex sample with double bromine - iodine labelling targeting a large group of bacteria and a specific archaea to evaluate their specific (13C uptake during labelled methanol anaerobic degradation.

  14. Concentration-dependent apparent partition coefficients of ionic liquids possessing ethyl- and bi-sulphate anions.

    Science.gov (United States)

    Jain, Preeti; Kumar, Anil

    2016-01-14

    This study deals with the concentration dependent apparent partition coefficients log P of the ethyl and bisulfate-based ionic liquids. It is observed that the bisulfate-based ionic liquids show different behaviour with respect to concentration as compared to ethyl sulphate-based ionic liquids. It is significant and useful analysis for the further implementation of alkyl sulfate based ionic liquids as solvents in extraction processes. The log P values of the ethyl sulphate-based ionic liquids were noted to vary linearly with the concentration of the ionic liquid, whereas a flip-flop trend with the concentration for the log P values of the bisulphate-based ionic liquids was observed due to the difference in hydrogen bond accepting basicity and possibility of aggregate formation of these anions. The π-π interactions between the imidazolium and pyridinium rings were seen to affect the log P values. The alkyl chain length of anions was also observed to influence the log P values. The hydrophobicity of ionic liquid changes with the alkyl chain in the anion in the order; [HSO4](-) < [EtSO4](-) < [BuSO4](-).

  15. Widespread of H5N1 infections in apparently healthy backyard poultry.

    Science.gov (United States)

    Abozaid, Khaled G A; Aly, Mona M; Abdel-Moneim, Ahmed S; El-Kady, Magdy F

    2016-08-01

    Highly pathogenic avian influenza subtype H5N1 represents a threat to the poultry industry and human health worldwide. Inapparently infected birds are suspected to play an essential role in the spread of avian influenza virus. In the current study, a total of 25,646 samples (16,185 chicken, 4696 ducks, 1633 geese and 3132 turkeys) from apparently healthy birds were screened for the presence of positive samples for H5N1 during 2009-2014. The samples were examined by reverse transcriptase real-time polymerase chain reaction (rRT-PCR) for M, H5 and N1 genes of avian influenza viruses. The results revealed that the HPAI H5N1 existed in an inapparent manner in ducks (4.68 %), geese (4.10 %), chickens (2.48 %) and turkeys (2.29 %). The current finding highlights the serious impact of such type on birds in the epidemiology of H5N1 in birds, animals and humans. It also highlights the existence of another reason other than vaccination that contributes to the widespread of inapparent infection of H5N1 in Egypt.

  16. Reconstruction of apparent orthotropic conductivity tensor image using magnetic resonance electrical impedance tomography

    Energy Technology Data Exchange (ETDEWEB)

    Sajib, Saurav Z. K.; Kim, Ji Eun; Jeong, Woo Chul; Kim, Hyung Joong; Woo, Eung Je [Department of Biomedical Engineering, Kyung Hee University, Yongin, Gyeonggi (Korea, Republic of); Kwon, Oh In, E-mail: oikwon@konkuk.ac.kr [Department of Mathematics, Konkuk University, Seoul (Korea, Republic of)

    2015-03-14

    Magnetic resonance electrical impedance tomography visualizes current density and/or conductivity distributions inside an electrically conductive object. Injecting currents into the imaging object along at least two different directions, induced magnetic flux density data can be measured using a magnetic resonance imaging scanner. Without rotating the object inside the scanner, we can measure only one component of the magnetic flux density denoted as B{sub z}. Since the biological tissues such as skeletal muscle and brain white matter show strong anisotropic properties, the reconstruction of anisotropic conductivity tensor is indispensable for the accurate observations in the biological systems. In this paper, we propose a direct method to reconstruct an axial apparent orthotropic conductivity tensor by using multiple B{sub z} data subject to multiple injection currents. To investigate the anisotropic conductivity properties, we first recover the internal current density from the measured B{sub z} data. From the recovered internal current density and the curl-free condition of the electric field, we derive an over-determined matrix system for determining the internal absolute orthotropic conductivity tensor. The over-determined matrix system is designed to use a combination of two loops around each pixel. Numerical simulations and phantom experimental results demonstrate that the proposed algorithm stably determines the orthotropic conductivity tensor.

  17. Effect of live yeast (Saccharomyces cerevisiae administration on apparent digestibility of horses

    Directory of Open Access Journals (Sweden)

    Giovanni Savoini

    2010-01-01

    Full Text Available Six mares were divided into two groups of three subjects each in a crossover design on the basis of body weight and age: Control(Cfedabasaldiet,Treatment(Tfedabasaldietand2 Control (C fed a basal diet, Treatment (T fed a basal diet and 2 2 g/head/d of live yeast ((S. cerevisiae 4.6x1010 CFU/day.Theexperimentaldesignwasdividedintotwo .Theexperimentaldesignwasdividedintotwo . The experimental design was divided into two periods named period 1 and period 2 respectively of 35d each, and consisting of 3 different phases. Dur- ing each period all animals were subject to an adaptation phase of 14d (phase1; during phase 2 (18d and phase 3 live yeast was administered (T or not (C. Phase 3 consisted in a three days individual fecal collection period all the groups, in order to determine dry matter, organic matter, crude protein, crude fat, NDF and ADF apparent digestion rates using acid insoluble ash (AIA as internal marker (Bergero et al., 2005. Results obtained evidenced as the administration of S. cerevisiae to mature horses resulted in increased digestibility of dry matter, organic matter, NDF, and ADF.

  18. High prevalence of asymptomatic malaria in apparently healthy schoolchildren in Aliero, Kebbi state, Nigeria

    Directory of Open Access Journals (Sweden)

    Rupashree Singh

    2014-04-01

    Full Text Available Background & objectives: In malaria endemic areas, continuous exposure to Plasmodium parasites leads to asymptomatic carriers that provide a reservoir, contributing to the persistence of malaria transmission. Thus, a study of the degree of prevalence of asymptomatic parasitaemias will help in assessing the level of reservoir of infection. Methods: All the consented participants without any signs and symptoms, suggestive of malaria were interviewed and thick blood smears were made to detect malaria parasites. The children presenting with malaria or any other severe illness, and those declining to give consent were excluded from the study. Results: A total of 118 (59.6% children out of 198 apparently healthy children were positive for malaria parasites while 80 (40.4% children were negative for malaria parasites. Prevalence of asymptomatic malaria was higher in males 75 (63.6% compared to females 43 (36.4%, but the difference was not statistically significant. Incidence of asymptomatic malaria was highest with 76.1% in the children aged 6– 10 yr. There was statistically significant association of the use of bednet on prevalence of asymptomatic malaria. Interpretation & conclusion: High prevalence of asymptomatic malaria detected in this study is a big challenge and can be a threat to the present malaria control programme. Thus, it should be considered in assessing and reorganising more effective malaria elimination strategies to achieve the desired goal of malaria control.

  19. Optical study of thin-film photovoltaic cells with apparent optical path length

    Science.gov (United States)

    Cho, Changsoon; Jeong, Seonju; Lee, Jung-Yong

    2016-09-01

    Extending the insufficient optical path length (OPL) in thin-film photovoltaic cells (PVs) is the key to achieving a high power conversion efficiency (PCE) in devices. Here, we introduce the apparent OPL (AOPL) as a figure of merit for light absorbing capability in thin-film PVs. The optical characteristics such as the structural effects and angular responses in thin-film PVs were analyzed in terms of the AOPL. Although the Lambertian scattering surface yields a broadband absorption enhancement in thin-film PVs, the enhancement is not as effective as in thick-film PVs. On the other hand, nanophotonic schemes are introduced as an approach to increasing the single-pass AOPL by inducing surface plasmon resonance. The scheme using periodic metal gratings is proved to increase the AOPL in a narrow wavelength range and specific polarization, overcoming the Yablonovitch limit. The AOPL calculation can be also adopted in the experimental analysis and a maximum AOPL of 4.15d (where d is the active layer thickness) is exhibited in the absorption band edge region of PTB7:PC70BM-based polymer PVs.

  20. Regional apparent diffusion coefficient values in 3rd trimester fetal brain

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, Chen [Tel Aviv University, Department of Radiology, Sheba Medical Center, Tel Hashomer (affiliated to the Sackler School of Medicine), Tel Aviv (Israel); Sheba Medical Center, Diagnostic Imaging, 52621, Tel Hashomer (Israel); Weisz, Boaz; Lipitz, Shlomo; Katorza, Eldad [Tel Aviv University, Department of Obstetrics and Gynecology, Sheba Medical Center, Tel Hashomer (affiliated to the Sackler School of Medicine), Tel Aviv (Israel); Yaniv, Gal; Bergman, Dafi [Tel Aviv University, Department of Radiology, Sheba Medical Center, Tel Hashomer (affiliated to the Sackler School of Medicine), Tel Aviv (Israel); Biegon, Anat [Stony Brook University School of Medicine, Department of Neurology, Stony Brook, NY (United States)

    2014-07-15

    Apparent diffusion coefficient (ADC) values in the developing fetus can be used in the diagnosis and prognosis of prenatal brain pathologies. To this end, we measured regional ADC in a relatively large cohort of normal fetal brains in utero. Diffusion-weighted imaging (DWI) was performed in 48 non-sedated 3rd trimester fetuses with normal structural MR imaging results. ADC was measured in white matter (frontal, parietal, temporal, and occipital lobes), basal ganglia, thalamus, pons, and cerebellum. Regional ADC values were compared by one-way ANOVA with gestational age as covariate. Regression analysis was used to examine gestational age-related changes in regional ADC. Four other cases of CMV infection were also examined. Median gestational age was 32 weeks (range, 26-33 weeks). There was a highly significant effect of region on ADC, whereby ADC values were highest in white matter, with significantly lower values in basal ganglia and cerebellum and the lowest values in thalamus and pons. ADC did not significantly change with gestational age in any of the regions tested. In the four cases with fetal CMV infection, ADC value was associated with a global decrease. ADC values in normal fetal brain are relatively stable during the third trimester, show consistent regional variation, and can make an important contribution to the early diagnosis and possibly prognosis of fetal brain pathologies. (orig.)

  1. No apparent ecological trend to the flight-initiating jump performance of five bat species.

    Science.gov (United States)

    Gardiner, James D; Nudds, Robert L

    2011-07-01

    The jump performance of five insectivorous bat species (Miniopterus schreibersii, Myotis blythii, Myotis capaccinii, Myotis myotis and Rhinolophus blasii) was filmed using a high-speed camera. All study bats jumped using a similar technique, with the wing musculature providing the force. The bats jumped off the wrist joint of their wings, typically with their feet already off the ground. Contrary to expectations, jump performance did not correlate with ecology and was instead strongly determined by body size. In general, the larger bats produced more jump force, left the ground at higher speeds and jumped higher than the smaller bats. The differences in force production disappeared when the data were corrected for body size, with the exception of Myotis capaccinii, which produced significantly less force. Scaling of jump performance with body size measured here was compared against two existing muscle performance scaling models. The model suggesting that muscle contraction velocity is proportional to muscle length was better supported than that based on muscle cross-sectional area. Both models, however, failed to accurately predict the scaling of jump forces, with the slope of the relationship being significantly steeper than predicted, highlighting the need for further investigations of vertebrate muscle performance scaling. The results of this study indicate that a bat's jumping ability is a secondary locomotor ability that uses the strongly selected-for flight apparatus with no apparent ecological trend present, i.e. flight so dominates bat locomotor morphology that other locomotor abilities tend to be derivative.

  2. Invasive orbital aspergillosis in an apparently immunocompetent host without evidence of sinusitis

    Directory of Open Access Journals (Sweden)

    Jennifer Primeggia

    2012-09-01

    Full Text Available Invasive aspergillosis is uncommon in healthy individuals. We report a case of Aspergillus fumigatus orbital cellulitiswith intracranial extension in an apparently immunocompetent patient with a history of benign lymphoid hyperplasiaof the lacrimal gland. A 68 year-old man with no significant past medical history underwent orbitotomy and biopsy of alacrimal gland mass. Pathology showed benign lymphoid hyperplasia of the lacrimal gland and he completed radiationtherapy. Three months after orbitotomy and one month after completion of radiation therapy, he presented with orbitalcellulitis. Brain magnetic resonance imaging demonstrated invasion into the frontal lobe. Clinical and radiographicfindings failed to improve with prolonged antibiotic therapy; transcranial orbitotomy with right frontal craniotomy forabscess drainage and orbit washout was performed. Intraoperative cultures grew Aspergillus fumigatus. The patientcompleted a six month course of therapy with oral voriconazole and has remained free from relapse with long-termfollow-up. Efficacy of voriconazole was guided by serial imaging and voriconazole trough levels. Aspergillus may causeinvasive disease in immunocompetent hosts, even without evidence of sinusitis, and should be considered in the differentialdiagnosis when patients do not demonstrate clinical improvement with antibiotic therapy. J Microbiol Infect Dis2012; 2(3: 113-116Key words: Aspergillosis, orbital cellulitis, brain abscess

  3. State-dependent decisions cause apparent violations of rationality in animal choice.

    Directory of Open Access Journals (Sweden)

    Cynthia Schuck-Paim

    2004-12-01

    Full Text Available Normative models of choice in economics and biology usually expect preferences to be consistent across contexts, or "rational" in economic language. Following a large body of literature reporting economically irrational behaviour in humans, breaches of rationality by animals have also been recently described. If proven systematic, these findings would challenge long-standing biological approaches to behavioural theorising, and suggest that cognitive processes similar to those claimed to cause irrationality in humans can also hinder optimality approaches to modelling animal preferences. Critical differences between human and animal experiments have not, however, been sufficiently acknowledged. While humans can be instructed conceptually about the choice problem, animals need to be trained by repeated exposure to all contingencies. This exposure often leads to differences in state between treatments, hence changing choices while preserving rationality. We report experiments with European starlings demonstrating that apparent breaches of rationality can result from state-dependence. We show that adding an inferior alternative to a choice set (a "decoy" affects choices, an effect previously interpreted as indicating irrationality. However, these effects appear and disappear depending on whether state differences between choice contexts are present or not. These results open the possibility that some expressions of maladaptive behaviour are due to oversights in the migration of ideas between economics and biology, and suggest that key differences between human and nonhuman research must be recognised if ideas are to safely travel between these fields.

  4. Measurement depth effects on the apparent temperature sensitivity of soil respiration in field studies

    Directory of Open Access Journals (Sweden)

    A. Graf

    2008-05-01

    Full Text Available CO2 efflux at the soil surface is the result of respiration in different depths that are subjected to variable temperatures at the same time. Therefore, the temperature measurement depth affects the apparent temperature sensitivity of field-measured soil respiration. We summarize existing literature evidence on the importance of this effect, and describe a simple model to understand and estimate the magnitude of this potential error source for heterotrophic respiration. The model is tested against field measurements. We discuss the influence of climate (annual and daily temperature amplitude, soil properties (vertical distribution of CO2 sources, thermal and gas diffusivity, and measurement schedule (frequency, study duration, and time averaging. Q10 as a commonly used parameter describing the temperature sensitivity of soil respiration is taken as an example and computed for different combinations of the above conditions. We define conditions and data acquisition and analysis strategies that lead to lower errors in field-based Q10 determination. It was found that commonly used temperature measurement depths are likely to result in an underestimation of temperature sensitivity in field experiments. Our results also apply to activation energy as an alternative temperature sensitivity parameter.

  5. Measurement depth effects on the apparent temperature sensitivity of soil respiration in field studies

    Directory of Open Access Journals (Sweden)

    A. Graf

    2008-08-01

    Full Text Available CO2 efflux at the soil surface is the result of respiration in different depths that are subjected to variable temperatures at the same time. Therefore, the temperature measurement depth affects the apparent temperature sensitivity of field-measured soil respiration. We summarize existing literature evidence on the importance of this effect, and describe a simple model to understand and estimate the magnitude of this potential error source for heterotrophic respiration. The model is tested against field measurements. We discuss the influence of climate (annual and daily temperature amplitude, soil properties (vertical distribution of CO2 sources, thermal and gas diffusivity, and measurement schedule (frequency, study duration, and time averaging. Q10 as a commonly used parameter describing the temperature sensitivity of soil respiration is taken as an example and computed for different combinations of the above conditions. We define conditions and data acquisition and analysis strategies that lead to lower errors in field-based Q10 determination. It was found that commonly used temperature measurement depths are likely to result in an underestimation of temperature sensitivity in field experiments. Our results also apply to activation energy as an alternative temperature sensitivity parameter.

  6. A statistical representation of the cosmological constant from finite size effects at the apparent horizon

    CERN Document Server

    Viaggiu, Stefano

    2016-01-01

    In this paper we present a statistical description of the cosmological constant in terms of massless bosons (gravitons). To this purpose, we use our recent results implying a non vanishing temperature ${T_{\\Lambda}}$ for the cosmological constant. In particular, we found that a non vanishing $T_{\\Lambda}$ allows us to depict the cosmological constant $\\Lambda$ as composed of elementary oscillations of massless bosons of energy $\\hbar\\omega$ by means of the Bose-Einstein distribution. In this context, as happens for photons in a medium, the effective phase velocity $v_g$ of these massless excitations is not given by the speed of light $c$ but it is suppressed by a factor depending on the number of quanta present in the universe at the apparent horizon. We found interesting formulas relating the cosmological constant, the number of quanta $N$ and the mean value $\\overline{\\lambda}$ of the wavelength of the gravitons. In this context, we study the possibility to look to the gravitons system so obtained as being ...

  7. Multiple concurrent temporal recalibrations driven by audiovisual stimuli with apparent physical differences.

    Science.gov (United States)

    Yuan, Xiangyong; Bi, Cuihua; Huang, Xiting

    2015-05-01

    Out-of-synchrony experiences can easily recalibrate one's subjective simultaneity point in the direction of the experienced asynchrony. Although temporal adjustment of multiple audiovisual stimuli has been recently demonstrated to be spatially specific, perceptual grouping processes that organize separate audiovisual stimuli into distinctive "objects" may play a more important role in forming the basis for subsequent multiple temporal recalibrations. We investigated whether apparent physical differences between audiovisual pairs that make them distinct from each other can independently drive multiple concurrent temporal recalibrations regardless of spatial overlap. Experiment 1 verified that reducing the physical difference between two audiovisual pairs diminishes the multiple temporal recalibrations by exposing observers to two utterances with opposing temporal relationships spoken by one single speaker rather than two distinct speakers at the same location. Experiment 2 found that increasing the physical difference between two stimuli pairs can promote multiple temporal recalibrations by complicating their non-temporal dimensions (e.g., disks composed of two rather than one attribute and tones generated by multiplying two frequencies); however, these recalibration aftereffects were subtle. Experiment 3 further revealed that making the two audiovisual pairs differ in temporal structures (one transient and one gradual) was sufficient to drive concurrent temporal recalibration. These results confirm that the more audiovisual pairs physically differ, especially in temporal profile, the more likely multiple temporal perception adjustments will be content-constrained regardless of spatial overlap. These results indicate that multiple temporal recalibrations are based secondarily on the outcome of perceptual grouping processes.

  8. Study on Apparent Kinetic Prediction Model of the Smelting Reduction Based on the Time-Series

    Directory of Open Access Journals (Sweden)

    Guo-feng Fan

    2012-01-01

    Full Text Available A series of direct smelting reduction experiment has been carried out with high phosphorous iron ore of the different bases by thermogravimetric analyzer. The derivative thermogravimetric (DTG data have been obtained from the experiments. One-step forward local weighted linear (LWL method , one of the most suitable ways of predicting chaotic time-series methods which focus on the errors, is used to predict DTG. In the meanwhile, empirical mode decomposition-autoregressive (EMD-AR, a data mining technique in signal processing, is also used to predict DTG. The results show that (1 EMD-AR(4 is the most appropriate and its error is smaller than the former; (2 root mean square error (RMSE has decreased about two-thirds; (3 standardized root mean square error (NMSE has decreased in an order of magnitude. Finally in this paper, EMD-AR method has been improved by golden section weighting; its error would be smaller than before. Therefore, the improved EMD-AR model is a promising alternative for apparent reaction rate (DTG. The analytical results have been an important reference in the field of industrial control.

  9. Atmospheric new particle formation: real and apparent growth of neutral and charged particles

    Directory of Open Access Journals (Sweden)

    J. Leppä

    2011-01-01

    Full Text Available In this study we have provided simple analytical formulae to estimate the growth rate of a nucleation mode due to self-coagulation and the apparent growth rate due to coagulation scavenging by larger particles. These formulae were used on a set of simulations covering a wide range of atmospheric conditions. The modal growth rates were determined from the simulation results by summing the contribution of each process, by calculating the increase rate in the count mean diameter of the mode and by following the peak concentration of the mode. The results of these three methods were compared with each other and the means used to estimate the growth rate due to self-coagulation and coagulation scavenging were found to work quite well. We also investigated the role of charged particles and electric interactions in the growth of a nucleation mode. Charged particles were found to increase the growth rate due to both self-coagulation and coagulation scavenging by a factor of ~1.5 to 2. In case of increased condensation onto charged particles, the total condensational growth rate of a nucleation mode may increase significantly in the very early steps of the growth. The analytical formulae provided by this paper were designed to provide the growth rates due to different processes from aerosol dynamic simulations, but the same principles can be used to determine the growth rates from measurement data.

  10. Atmospheric new particle formation: real and apparent growth of neutral and charged particles

    Directory of Open Access Journals (Sweden)

    J. Leppä

    2011-05-01

    Full Text Available In this study we have provided simple analytical formulae to estimate the growth rate of a nucleation mode due to self-coagulation and the apparent growth rate due to coagulation scavenging by larger particles. These formulae were used on a set of simulations covering a wide range of atmospheric conditions. The modal growth rates were determined from the simulation results by summing the contribution of each process, by calculating the increase rate in the count mean diameter of the mode and by following the peak concentration of the mode. The results of these three methods were compared with each other and the means used to estimate the growth rate due to self-coagulation and coagulation scavenging were found to give accurate values. We also investigated the role of charged particles and electric interactions in the growth of a nucleation mode. Charged particles were found to increase the growth rate due to both self-coagulation and coagulation scavenging by a factor of ~1.5 to 2. In case of increased condensation onto charged particles, the total condensational growth rate of a nucleation mode may increase significantly in the very early steps of the growth. The analytical formulae provided by this paper were designed to provide the growth rates due to different processes from aerosol dynamic simulations, but the same principles can be used to determine the growth rates from measurement data.

  11. Testicular cytological profiles of apparently healthy male dromedary camels during rutting and non-rutting periods.

    Science.gov (United States)

    Melaku, Simenew Keskes; Regassa, Fekadu; Tessema, Tesfaye Sisay; Kassa, Tesfu; Vencato, Juri; Owiny, David Okello; Stelletta, Calogero

    2015-12-01

    The aim of this study was to evaluate testicular cytological profiles of apparently healthy dromedary bulls during rutting and non-rutting periods. Pairs of testes from 26 (18 non-rutting and 8 rutting seasons) dromedary bulls 6-12 years old that were slaughtered at Akaki, Addis Ababa abattoir were sampled. A 21 gauge needle attached to 20mL syringe was used to collect Testicular Fine Needle Aspiration (TFNA) samples and five aspiration smears were prepared from each testis. A total of 312 slides (260 Testicular fine Needle Aspiration and 52 imprints) were examined. The mod ified May-Grunwald Giemsa (mMGG) technique and a light microscope were used to assess cellularity, morphology and quantification of the testicular. Sertoli and spermatogenic cells were identified and counted. The spermatic index (SI), Sertoli cell index (SEI) and the relationship between SI and SEI indexes (SSEI) were used to assess the ratio between mature spermatozoa and nursing cells. There were differences (P0.05) between TFNA and imprint smear slides of the testicular cells except for Sertoli cell count and SEI. Filarial worm larvae were present on the TFNA smear slides of four animals. Imprint and TFNA smear slides had comparable cytological profiles in dromedary bulls and significant differences were observed between rutting and non-rutting periods.

  12. Apparent auditory source width insensitivity in older hearing-impaired individuals.

    Science.gov (United States)

    Whitmer, William M; Seeber, Bernhard U; Akeroyd, Michael A

    2012-07-01

    Previous studies have shown a loss in the precision of horizontal localization responses of older hearing-impaired (HI) individuals, along with potentially poorer neural representations of sound-source location. These deficits could be the result or corollary of greater difficulties in discriminating spatial images, and the insensitivity to punctate sound sources. This hypothesis was tested in three headphone-presentation experiments varying interaural coherence (IC), the cue most associated with apparent auditory source width. First, thresholds for differences in IC were measured for a broad sampling of participants. Older HI participants were significantly worse at discriminating IC across reference values than younger normal-hearing participants. These results are consistent with senescent increases in temporal jitter. Performance decreased with age, a finding corroborated in a second discrimination experiment using a separate group of participants matched for hearing loss. This group also completed a third, visual experiment, with both a cross-mapping task where they drew the size of the sound they heard and the identification task where they chose the image that best corresponded to what they heard. The results from the visual tasks indicate that older HI individuals do not hear punctate images and are relatively insensitive to changes in width based on IC.

  13. Changes in body composition in apparently healthy urban Indian women up to 3 years postpartum

    Directory of Open Access Journals (Sweden)

    Neha A Kajale

    2015-01-01

    Full Text Available Introduction: Dietary and life style practices differ in postpartum (PP and nonpregnant Indian women. Effect of these practices on postpartum weight retention (PPWR and development of cardio-metabolic risk (CMR has been scarcely studied in urban women. Aims of this study were to (i compare anthropometry, biochemical parameters and body composition up to 3 years PP (ii effect of PPWR, dietary fat intake and physical activity on CMR factors. Methods: Design: Cross-sectional, 300-fullterm, apparently healthy primi-parous women (28.6 ± 3.4 years randomly selected. 128 women within 7-day of delivery (Group-A, 88 with 1-2 years (Group-B and 84 with 3-4-year-old-children (Group-C were studied. Anthropometry, sociodemographic status, physical activity, diet, clinical examination, biochemical tests, body composition, at total body (TB, by dual energy X-ray absorptiometry (GE-Lunar DPX were collected. Results: Women at 3-year PP showed higher weight retention (6.5[10] kg than at 1-year (3.0[7] kg (median [IQR]. Android fat % (central obesity increased (P 0.1. Conclusion: Postdelivery, low physical activity and higher PPWR may increase CMR in Indian women.

  14. Is fish oil good or bad for heart disease? Two trials with apparently conflicting results.

    Science.gov (United States)

    Burr, M L; Dunstan, F D J; George, C H

    2005-07-01

    Two successive randomized trials examined the effect of an increased intake of fatty fish, or the use of fish oil supplements, in reducing mortality in men with heart disease. The Diet and Reinfarction Trial (DART) was conducted in 2033 men who were recovering from acute myocardial infarction (MI). Those who were advised to eat fatty fish (or who opted to take fish oil capsules instead) had a 29% reduction in all-cause mortality over the following two years compared with those not so advised. The effect appeared in the first few months of the trial. The Diet and Angina Randomized Trial (DART 2) involved 3114 men with stable angina. Advice to eat fatty fish did not reduce mortality, and taking fish oil capsules was associated with a higher risk of cardiac and sudden death. The adverse effects of fish or fish oil were restricted to men not taking beta-blockers or dihydropyridine calcium-channel blockers, and were greater in those taking digoxin. Evidence from other sources strongly suggests an anti-arrhythmic action of fish oil, particularly after MI or in the presence of acute ischemia. The apparently conflicting results of the two trials may reflect different actions of n-3 fatty acids in acute and chronic conditions, together with different effects of eating fish and taking fish oil capsules. A mechanism is proposed that could account for these findings.

  15. Considerations about the apparent ''superluminal expansions'' observed in astrophysics

    Energy Technology Data Exchange (ETDEWEB)

    Recami, E.; Castellino, A.; Maccarrone, G.D.; Rodono, M.

    1986-06-11

    The orthodox models devised to explain the apparent ''superluminal expansions'' observed in astrophysics - and here briefly summarized and discussed together with the experimental data - do not seem to be too much successful, especially when confronted with the most recent observations, suggesting complicated expansion patterns, even with possible accelerations. At this point it may be, therefore, of some interest to explore the possible alternative models in which actual Superluminal motions take place. To prepare the ground, we start from a variational principle, introduce the elements of a tachyon mechanics within special relativity, and argue about the expected behaviour of tachyonic objects when interacting (gravitationally, for instance) among themselves or with ordinary matter. We then review and develop the simplet ''Superluminal models'', paying particular attention to the observations which they would give rise to. We conclude that some of them appear to be physically acceptable and are statistically favoured with respect to the orthodox ones.

  16. In vivo non-thermal irreversible electroporation impact on rat liver galvanic apparent internal resistance

    Science.gov (United States)

    Golberg, A.; Laufer, S.; Rabinowitch, H. D.; Rubinsky, B.

    2011-02-01

    Non-thermal irreversible electroporation (NTIRE) is a biophysical phenomenon which involves application of electric field pulses to cells or tissues, causing certain rearrangements in the membrane structure leading to cell death. The treated tissue ac impedance changes induced by electroporation were shown to be the indicators for NTIRE efficiency. In a previous study we characterized in vitro tissue galvanic apparent internal resistance (GAIR) changes due to NTIRE. Here we describe an in vivo study in which we monitored the GAIR changes of a rat liver treated by NTIRE. Electrical pulses were delivered through the same Zn/Cu electrodes by which GAIR was measured. GAIR was measured before and for 3 h after the treatment at 15 min intervals. The results were compared to the established ac bioimpedance measurement method. A decrease of 33% was measured immediately after the NTIRE treatment and a 40% decrease was measured after 3 h in GAIR values; in the same time 40% and 47% decrease respectively were measured by ac bioimpedance analyses. The temperature increase due to the NTIRE was only 0.5 °C. The results open the way for an inexpensive, self-powered in vivo real-time NTIRE effectiveness measurement.

  17. Detection of Yersinia spp and Salmonella spp. in apparently healthy cats and dogs in Tehran, Iran

    Directory of Open Access Journals (Sweden)

    shabnam hashemi

    2016-03-01

    Full Text Available Introduction: Companion animals, such as cat and dog, are potential sources of transmissible diseases to humans, especially children. They harbor zoonotic agents in gastrointestinal tracts as carriers which are capable of infecting their owners. Salmonella and Yersinia bacteria are considered as frequent causes of illness in children. This study was aimed at finding out the prevalence rate of infection in apparently healthy dogs and cats in Tehran, Iran. Materials and methods: A total of 100 rectal swabs from dogs and cats were analyzed by a multiplex PCR method with specific primers for detection of Yersinia and Salmonella species. Results: Fifteen samples (4 cats and 11 dogs were positive for Yersinia and 20 samples (9 cats and 11 dogs were positive for Salmonella. So the prevalence rate of Yersinia was 8% in cats and 22% in dogs and the prevalence rates of Salmonella were 18 and 22% in cats and dogs respectively. Discussion and conclusion: According to the results, Yersinia and Salmonella were detected in 8- 22% of pet animals without any clinical signs. The contaminated animal foods may be the main source of infection. These results may be useful in planning control and preventive programs. 

  18. Apparently-deep events in the Middle Atlas resolved to be shallow: Implications for lithospheric deformation

    Science.gov (United States)

    Singh, Shashwat K.; Bezada, Maximiliano J.; Elouai, Driss; Harnafi, Mimoun

    2016-11-01

    The occurrence of intermediate depth seismicity in intracontinental settings is rare, but it has been postulated with various degrees of certainty in several regions. One such region is the Middle Atlas of Morocco. Since 1960, 75 intermediate depth earthquakes have been reported in this region by Spain's National Geographic Institute (IGN). The apparent deep nature of these events is hard to reconcile with well-established geophysical evidence of a thin lithosphere under the Middle Atlas, but has been associated with mantle delamination processes. We relocate 4 events with IGN-reported depths > 80 km that were recorded by a relatively dense temporary deployment; using a recent regional 3D velocity model obtained through teleseismic body and surface wave tomography. The relocation procedure uses a grid-search approach to minimize the mean normalized misfit, where each travel-time misfit is normalized by the estimated pick uncertainty. We find that our observed arrivals are much better fit by shallow ( 80 km. We propose that these shallow foci earthquakes are the result of regional crustal deformation of this region caused by the present convergence between Africa and Eurasian Plate. We infer that if there are any ongoing delamination processes in the area, they are aseismic. This study is an example of how local earthquake locations in tectonically complex areas can be significantly improved by using a dense local seismic array and a well-constrained 3-D velocity model.

  19. Apparent contact angles induced by evaporation into air: interferometric measurements and lubrication-type modeling

    Science.gov (United States)

    Colinet, Pierre; Tsoumpas, Yannis; Dehaeck, Sam; Rednikov, Alexey

    2014-11-01

    For volatile liquids, finite contact angles on solid substrates can occur even in the case of perfect wetting, immobile contact lines and ideally smooth surfaces. This is a fluid-dynamic effect due to evaporation typically intensifying towards a small vicinity of the contact line. In the present talk, we first overview recent theoretical results on the subject, where we focus primarily on the case of diffusion-limited evaporation into air. The model is based upon the so-called de Gennes' paradigm, incorporating simultaneously the spreading coefficient and the disjoining pressure in the form of an inverse cubic law. Then we carry out comparison with experimental results for the contact angles of evaporating sessile drops of several perfectly-wetting HFE liquids of different volatility recently obtained by Mach-Zehnder interferometry. The scaling-type theoretical prediction for the apparent contact angle is found to be in good agreement with experimental measurements. Another model based upon the Kelvin effect (curvature dependence of the saturation conditions) is also briefly discussed, an important conceptual feature of which being that contact-line singularities (both evaporation- and motion-induced) can be fully regularized, in contrast with the first model. Support from ESA, BELSPO and FRS-FNRS is gratefully acknowledged.

  20. Origin of the excess IR luminosity in an apparently isolated LIRG

    Science.gov (United States)

    Cárdenas-Martínez, N.; Fuentes-Carrera, I.

    2016-06-01

    LIRGs and ULIRGs have long been recognized as one of the best laboratories to study the process of violent star formation in the Local Universe. In order for a star forming galaxy to emit at a LIRG level, it must have a very high star formation rate (SFR). In the local Universe, these high SFR are primarily triggered by galaxy-galaxy interactions or mergers. However, several authors show that roughly 50% of intermediate redshift LIRGs are disk galaxies without sign of recent interactions. The question arises regarding which processes could be originating such an enhanced SF. We present the extended kinematics of the ionized gas of an apparently isolated late-type galaxies displaying LIRG activity, as well as the morphological analysis from the UV to the MIR. We identify a morphological peculiarity which seems to be associated with double peaked profiles which could be related to two different kinematic components. We propose this to be a signature of an infalling satellite galaxy. CIG 302 might be an example of a minor interaction inducing very strong star formation in the local Universe.

  1. In vivo non-thermal irreversible electroporation impact on rat liver galvanic apparent internal resistance

    Energy Technology Data Exchange (ETDEWEB)

    Golberg, A; Laufer, S [Center for Bioengineering in the Service of Humanity and Society, School of Computer Science and Engineering, Hebrew University of Jerusalem, Jerusalem 91904 (Israel); Rabinowitch, H D [Robert H Smith Faculty of Agriculture, Food and Environment, Robert H Smith Institute of Plant Science and Genetics in Agriculture, Hebrew University of Jerusalem, Rehovot 76 100 (Israel); Rubinsky, B, E-mail: Rabin@agri.huji.ac.il [Department of Mechanical Engineering, Graduate Program in Biophysics, University of California at Berkeley, Berkeley, CA 84720 (United States)

    2011-02-21

    Non-thermal irreversible electroporation (NTIRE) is a biophysical phenomenon which involves application of electric field pulses to cells or tissues, causing certain rearrangements in the membrane structure leading to cell death. The treated tissue ac impedance changes induced by electroporation were shown to be the indicators for NTIRE efficiency. In a previous study we characterized in vitro tissue galvanic apparent internal resistance (GAIR) changes due to NTIRE. Here we describe an in vivo study in which we monitored the GAIR changes of a rat liver treated by NTIRE. Electrical pulses were delivered through the same Zn/Cu electrodes by which GAIR was measured. GAIR was measured before and for 3 h after the treatment at 15 min intervals. The results were compared to the established ac bioimpedance measurement method. A decrease of 33% was measured immediately after the NTIRE treatment and a 40% decrease was measured after 3 h in GAIR values; in the same time 40% and 47% decrease respectively were measured by ac bioimpedance analyses. The temperature increase due to the NTIRE was only 0.5 deg. C. The results open the way for an inexpensive, self-powered in vivo real-time NTIRE effectiveness measurement.

  2. Apparent rippling with honeycomb symmetry and tunable periodicity observed by scanning tunneling microscopy on suspended graphene

    Science.gov (United States)

    Georgi, A.; Nemes-Incze, P.; Szafranek, B.; Neumaier, D.; Geringer, V.; Liebmann, M.; Morgenstern, M.

    2016-11-01

    Suspended graphene is difficult to image by scanning probe microscopy due to the inherent van der Waals and dielectric forces exerted by the tip, which are not counteracted by a substrate. Here, we report scanning tunneling microscopy data of suspended monolayer graphene in constant-current mode, revealing a surprising honeycomb structure with amplitude of 50-200 pm and lattice constant of 10-40 nm. The apparent lattice constant is reduced by increasing the tunneling current I , but does not depend systematically on tunneling voltage V or scan speed vscan. The honeycomb lattice of the rippling is aligned with the atomic structure observed on supported areas, while no atomic corrugation is found on suspended areas down to the resolution of about 3 -4 pm. We rule out that the honeycomb structure is induced by the feedback loop using a changing vscan, that it is a simple enlargement effect of the atomic lattice, as well as models predicting frozen phonons or standing phonon waves induced by the tunneling current. Although we currently do not have a convincing explanation for the observed effect, we expect that our intriguing results will inspire further research related to suspended graphene.

  3. On the Apparent Orbital Inclination Change of the Extrasolar Transiting Planet TrES-2b

    CERN Document Server

    Scuderi, Louis J; Males, Jared R; Green, Elizabeth M; Close, Laird M

    2009-01-01

    On June 15, 2009 UT the transit of TrES-2b was detected using the University of Arizona's 1.55 meter Kuiper Telescope with 2.0-2.5 millimag RMS accuracy in the I-band. We find a central transit time of T_c = 2454997.76286 +/- 0.00035 HJD, an orbital period of P = 2.4706127 +/- 0.0000009 days, and an inclination angle of i = 83.92 +/- 0.05 degrees, which is consistent with our re-fit of the original I-band light curve of O'Donovan et al. (2006) where we find i = 83.84 +/- 0.05 degrees. We calculate an inclination change of Delta i = -0.08 +/- 0.071 degrees over the last 3 years, and as such, our observations rule out, at the ~11 sigma level, the apparent change of orbital inclination to i_predicted = 83.35 +/- 0.1 degrees as predicted by Mislis & Schmitt (2009) for our epoch. Indeed, we detect no significant changes in any of the orbital parameters of TrES-2b when comparing the original I-band light curve to our recent I-band light curve.

  4. Cryptic organisation within an apparently irregular rostrocaudal distribution of interneurons in the embryonic zebrafish spinal cord

    Energy Technology Data Exchange (ETDEWEB)

    Wells, Simon, E-mail: simon.wells@adelaide.edu.au [Discipline of Genetics, School of Molecular and Biomedical Sciences, University of Adelaide, Adelaide, South Australia 5005 (Australia); The Special Research Centre for the Molecular Genetics of Development, University of Adelaide, Adelaide, South Australia 5005 (Australia); Conran, John G., E-mail: john.conran@adelaide.edu.au [Ecology and Evolutionary Biology, School of Earth and Environmental Sciences, University of Adelaide, Adelaide, South Australia 5005 (Australia); Tamme, Richard, E-mail: rtamme@ttu.ee [Discipline of Genetics, School of Molecular and Biomedical Sciences, University of Adelaide, Adelaide, South Australia 5005 (Australia); Gaudin, Arnaud, E-mail: a.gaudin@uq.edu.au [School of Biomedical Sciences, University of Queensland, Brisbane, Queensland 4072 (Australia); Webb, Jonathan, E-mail: jonathan.webb@worc.ox.ac.uk [Discipline of Genetics, School of Molecular and Biomedical Sciences, University of Adelaide, Adelaide, South Australia 5005 (Australia); Lardelli, Michael, E-mail: michael.lardelli@adelaide.edu.au [Discipline of Genetics, School of Molecular and Biomedical Sciences, University of Adelaide, Adelaide, South Australia 5005 (Australia); The Special Research Centre for the Molecular Genetics of Development, University of Adelaide, Adelaide, South Australia 5005 (Australia)

    2010-11-15

    The molecules and mechanisms involved in patterning the dorsoventral axis of the developing vertebrate spinal cord have been investigated extensively and many are well known. Conversely, knowledge of mechanisms patterning cellular distributions along the rostrocaudal axis is relatively more restricted. Much is known about the rostrocaudal distribution of motoneurons and spinal cord cells derived from neural crest but there is little known about the rostrocaudal patterning of most of the other spinal cord neurons. Here we report data from our analyses of the distribution of dorsal longitudinal ascending (DoLA) interneurons in the developing zebrafish spinal cord. We show that, although apparently distributed irregularly, these cells have cryptic organisation. We present a novel cell-labelling technique that reveals that DoLA interneurons migrate rostrally along the dorsal longitudinal fasciculus of the spinal cord during development. This cell-labelling strategy may be useful for in vivo analysis of factors controlling neuron migration in the central nervous system. Additionally, we show that DoLA interneurons persist in the developing spinal cord for longer than previously reported. These findings illustrate the need to investigate factors and mechanisms that determine 'irregular' patterns of cell distribution, particularly in the central nervous system but also in other tissues of developing embryos.

  5. The Real, the Apparent, and What is eigentlich

    Directory of Open Access Journals (Sweden)

    Regine Eckardt

    2009-01-01

    Full Text Available In this paper, I will propose a uniform analysis for adjectival and certain instances of adverbial eigentlich. The analysis rests on the assumption that eigentlich contrasts the nominal content of a concept C with a contextually given notion of phenomenological evidence for C-hood. eigentlich offers the semantic frame to refer to two ways of C-hood which are usually supplied by context. In the adjectival use, the discourse content should provide an N exemplar in the true sense (an eigentliches N along with an apparent N, thereby proving the two notions to be different. In the adverbial use, the message conveyed is usually that the actual world nominally satisfies some proposition p (eigentlich, p while the actual world looks as if a contrasting proposition q were the case. The analysis improves on earlier accounts in German descriptive linguistics in that it offers a fully compositional account of the semantic and pragmatic contribution of eigentlich in a wide variety of constructions, including focus, contrastive topic and questions. The analysis proposes a delineation of eigentlich as an emotive marker which differs from the content use in prosody, syntax, focus sensitivity and meaning.

  6. Biosynthesis of Xanthan Gum from Fermenting Shrimp Shell: Yield and Apparent Viscosity

    Directory of Open Access Journals (Sweden)

    Larissa Alves de Sousa Costa

    2014-01-01

    Full Text Available With the aim of producing xanthan gum, the effects of an aqueous shrimp shell extract (SSAE as the source of carbon and nitrogen on the yield and apparent viscosity of the gums produced by fermentation using three native strains of Xanthomonas campestris were studied. It was found that the SSAE contained 89.75% moisture, 0.054% ash, 8.069% protein, 0.787 lipids, and 1.337% carbohydrates. Media containing different concentrations of SSAE and supplemented with urea (0.01% and phosphate (0.1% were fermented in a shaker, and the results obtained were compared with those obtained from sucrose (control with the same supplementation and fermentation conditions. Strain 1182 showed the highest yield (4.64 g·L−1 and viscosity (48.53 mPa·s, from the medium containing 10% (w/v of SSAE. These values were higher than those obtained from the control medium containing sucrose. Shrimp shell is a low cost residue that can be bioconverted into products of high added value such as xanthan gum.

  7. Fatal venous air embolism during anesthesia in an apparently healthy adult Chihuahua.

    Science.gov (United States)

    Mouser, Pamela J; Wilson, Jeffrey D

    2015-01-01

    An apparently healthy adult female Chihuahua was presented for elective ovariohysterectomy. After induction of general anesthesia, but prior to the start of the surgery, air was inadvertently administered to the patient via the i.v. fluid line. The patient convulsed, became apneic, arrested, and died despite attempted cardiopulmonary resuscitation. At necropsy, the pericardial sac was incised and filled with water to entirely submerge the intact heart. The right ventricular free wall was punctured, releasing several air bubbles from the right ventricle. Death was attributed to venous air embolism based on the clinical history, gross findings, and paucity of underlying gross and microscopic pathology that might have predisposed the dog to an anesthetic-related death. The discussion of this case includes a review of previously reported veterinary cases of fatal venous air embolism, including the varied mechanisms of embolus formation, the potential impact of pre-existing cardiopulmonary disease, and the methods used to detect emboli. This report outlines the events of fatal iatrogenic venous air embolization and emphasizes the importance of considering this entity in the case of sudden death of a patient with an indwelling catheter in order to pursue either appropriate diagnostic tests or necropsy techniques to aid in the diagnosis.

  8. On the Apparent Nulls and Extreme Variability of PSR J1107-5907

    CERN Document Server

    Young, N J; Stappers, B W; Lyne, A G; Kramer, M

    2014-01-01

    We present an analysis of the emission behaviour of PSR J1107-5907, a source known to exhibit separate modes of emission, using observations obtained over approximately 10 yr. We find that the object exhibits two distinct modes of emission; a strong mode with a broad profile and a weak mode with a narrow profile. During the strong mode of emission, the pulsar typically radiates very energetic emission over sequences of ~200-6000 pulses (~60 s-24 min), with apparent nulls over time-scales of up to a few pulses at a time. Emission during the weak mode is observed outside of these strong-mode sequences and manifests as occasional bursts of up to a few clearly detectable pulses at a time, as well as low-level underlying emission which is only detected through profile integration. This implies that the previously described null mode may in fact be representative of the bottom-end of the pulse intensity distribution for the source. This is supported by the dramatic pulse-to-pulse intensity modulation and rarity of ...

  9. A Fast Apparent-Horizon Finder for 3-Dimensional Cartesian Grids in Numerical Relativity

    CERN Document Server

    Thornburg, J

    2004-01-01

    In 3+1 numerical simulations of dynamic black hole spacetimes, it's useful to be able to find the apparent horizon(s) (AH) in each slice of a time evolution. A number of AH finders are available, but they often take many minutes to run, so they're too slow to be practically usable at each time step. Here I present a new AH finder,_AHFinderDirect_, which is very fast and accurate, typically taking only a few seconds to find an AH to $sim 10^{-5} m$ accuracy on a GHz-class processor. I assume that an AH to be searched for is a Strahlk"orper (star-shaped region) with respect to some local origin, and so parameterize the AH shape by $r = h(angle)$ for some single-valued function $h: S^2 to Re^+$. The AH equation then becomes a nonlinear elliptic PDE in $h$ on $S^2$, whose coefficients are algebraic functions of $g_{ij}$, $K_{ij}$, and the Cartesian-coordinate spatial derivatives of $g_{ij}$. I discretize $S^2$ using 6 angular patches (one each in the neighborhood of the $pm x$, $pm y$, and $pm z$ axes) to avoid c...

  10. Parameterization of the Age-Dependent Whole Brain Apparent Diffusion Coefficient Histogram

    Directory of Open Access Journals (Sweden)

    Uwe Klose

    2015-01-01

    Full Text Available Purpose. The distribution of apparent diffusion coefficient (ADC values in the brain can be used to characterize age effects and pathological changes of the brain tissue. The aim of this study was the parameterization of the whole brain ADC histogram by an advanced model with influence of age considered. Methods. Whole brain ADC histograms were calculated for all data and for seven age groups between 10 and 80 years. Modeling of the histograms was performed for two parts of the histogram separately: the brain tissue part was modeled by two Gaussian curves, while the remaining part was fitted by the sum of a Gaussian curve, a biexponential decay, and a straight line. Results. A consistent fitting of the histograms of all age groups was possible with the proposed model. Conclusions. This study confirms the strong dependence of the whole brain ADC histograms on the age of the examined subjects. The proposed model can be used to characterize changes of the whole brain ADC histogram in certain diseases under consideration of age effects.

  11. Drug therapy of apparent treatment-resistant hypertension: focus on mineralocorticoid receptor antagonists.

    Science.gov (United States)

    Glicklich, Daniel; Frishman, William H

    2015-04-01

    Apparent treatment-resistant hypertension (aTRH) is defined as blood pressure (BP) >140/90 mmHg despite three different antihypertensive drugs including a diuretic. aTRH is associated with an increased risk of cardiovascular events, including stroke, chronic renal failure, myocardial infarction, congestive heart failure, aortic aneurysm, atrial fibrillation, and sudden death. Preliminary studies of renal nerve ablation as a therapy to control aTRH were encouraging. However, these results were not confirmed by the Symplicity 3 trial. Therefore, attention has refocused on drug therapy. Secondary forms of hypertension and associated conditions such as obesity, sleep apnea, and primary aldosteronism are common in patients with aTRH. The pivotal role of aldosterone in the pathogenesis of aTRH in many cases is well recognized. For patients with aTRH, the Joint National Committee-8, the European Society of Hypertension, and a recent consensus conference recommend that a diuretic, ACE inhibitor, or angiotensin receptor blocker and calcium channel blocker combination be used to maximally tolerated doses before starting a 'fourth-line' drug such as a mineralocorticoid receptor (MR) antagonist. Although the best fourth-line drug for aTRH has not been extensively investigated, a number of studies summarized here show that an MR antagonist is effective in reducing BP when added to the standard multi-drug regimen.

  12. Environmental Report 1996, Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    Harrach, R.J.

    1996-01-01

    This is Volume 2 of the Lawrence Livermore National Laboratory`s (LLNL`s) annual Environmental Report 1996, prepared for the US Department of Energy. Volume 2 supports Volume 1 summary data and is essentially a detailed data report that provides individual data points, where applicable. Volume 2 includes information on monitoring of air, air effluents, sewerable water, surface water, ground water, soil and sediment, vegetation and foodstuff, environmental radiation, and quality assurance.

  13. Calculus Students' Understanding of Volume

    Science.gov (United States)

    Dorko, Allison; Speer, Natasha M.

    2013-01-01

    Researchers have documented difficulties that elementary school students have in understanding volume. Despite its importance in higher mathematics, we know little about college students' understanding of volume. This study investigated calculus students' understanding of volume. Clinical interview transcripts and written responses to volume…

  14. Cerebellar volume in patients with dementia Volume cerebelar em pacientes com demência

    Directory of Open Access Journals (Sweden)

    Leonardo Baldaçara

    2011-06-01

    Full Text Available OBJECTIVE: The aim of this study was to examine the cerebellar volume of subjects at different stages of Alzheimer's disease and to investigate whether volume reductions in this structure are related to cognitive decline. METHOD: Ninety-six subjects from an epidemiological study were submitted to a magnetic resonance imaging scan and evaluated using the Mini-Mental State Examination and the Functional Activities Questionnaire. Subjects were divided into five groups according to the Clinical Dementia Rating scale. Twenty-six subjects from the original group who had no dementia diagnosis at baseline were re-evaluated for the onset of dementia after two years. RESULTS: The volumes of the cerebellar hemispheres, posterior cerebellar lobe, vermis and temporal lobe were found to be reduced as a function of the severity of the disease. There were significant positive correlations between the volume of the temporal lobe and cerebellum and the language, attention, and total scores in the Mini-Mental State Examination and the Functional Activities Questionnaire. A logistic regression analysis demonstrated that reduced temporal lobe, posterior cerebellar lobe and vermal volume at baseline is a risk factor for the onset of dementia. CONCLUSION: This is the first study demonstrating that reduced cerebellar volume is already apparent at the predementia stage. The results of this study support the involvement of the cerebellum in the progression of dementia. Whereas the cerebellum might not be directly associated with the origin of Alzheimer's disease, it may provide useful information related to its prognosis.OBJETIVO: O objetivo deste estudo foi examinar o volume cerebelar em indivíduos em diferentes fases da doença de Alzheimer e investigar se sua redução estaria relacionada com o declínio cognitivo. MÉTODO: Noventa e seis indivíduos de um estudo epidemiológico foram submetidos à ressonância magnética e avaliados por meio do Mini Exame do Estado

  15. Cerebellar volume in patients with dementia Volume cerebelar em pacientes com demência

    Directory of Open Access Journals (Sweden)

    Leonardo Baldaçara

    2011-01-01

    Full Text Available OBJECTIVE: The aim of this study was to examine the cerebellar volume of subjects at different stages of Alzheimer's disease and to investigate whether volume reductions in this structure are related to cognitive decline. METHOD: Ninety-six subjects from an epidemiological study were submitted to a magnetic resonance imaging scan and evaluated using the Mini-Mental State Examination and the Functional Activities Questionnaire. Subjects were divided into five groups according to the Clinical Dementia Rating scale. Twenty-six subjects from the original group who had no dementia diagnosis at baseline were re-evaluated for the onset of dementia after two years. RESULTS: The volumes of the cerebellar hemispheres, posterior cerebellar lobe, vermis and temporal lobe were found to be reduced as a function of the severity of the disease. There were significant positive correlations between the volume of the temporal lobe and cerebellum and the language, attention, and total scores in the Mini-Mental State Examination and the Functional Activities Questionnaire. A logistic regression analysis demonstrated that reduced temporal lobe, posterior cerebellar lobe and vermal volume at baseline is a risk factor for the onset of dementia. CONCLUSION: This is the first study demonstrating that reduced cerebellar volume is already apparent at the predementia stage. The results of this study support the involvement of the cerebellum in the progression of dementia. Whereas the cerebellum might not be directly associated with the origin of Alzheimer's disease, it may provide useful information related to its prognosis.OBJETIVO: O objetivo deste estudo foi examinar o volume cerebelar em indivíduos em diferentes fases da doença de Alzheimer e investigar se sua redução estaria relacionada com o declínio cognitivo. MÉTODO: Noventa e seis indivíduos de um estudo epidemiológico foram submetidos à ressonância magnética e avaliados por meio do Mini Exame do Estado

  16. Volume of an Industrial Autoclave

    Directory of Open Access Journals (Sweden)

    Nicholas Madaffari

    2010-01-01

    Full Text Available We were able to determine the volume of an industrial autoclave sterilization tank using a technique learned in calculus. By measuring the dimensions of the tank and roughly estimating the equation of curvature at the ends of the tank, we were able to revolve half of the end of the tank around the x axis to get its fluid volume. Adding the two volumes of the ends and the volume of the cylindrical portion on the tank yielded the total volume.

  17. The apparent diffusion coefficient does not reflect cytotoxic edema on the uninjured side after traumatic brain injury

    Institute of Scientific and Technical Information of China (English)

    Hong Lu; Xiaoyan Lei

    2014-01-01

    After traumatic brain injury, vasogenic and cytotoxic edema appear sequentially on the in-volved side. Neuroimaging investigations of edema on the injured side have employed apparent diffusion coefficient measurements in diffusion tensor imaging. We investigated the changes occurring on the injured and uninjured sides using diffusion tensor imaging/apparent diffusion coefficient and histological samples in rats. We found that, on the injured side, that vasogen-ic edema appeared at 1 hour and intracellular edema appeared at 3 hours. Mixed edema was observed at 6 hours, worsening until 12-24 hours post-injury. Simultaneously, microglial cells proliferated at the trauma site. Apparent diffusion coefficient values increased at 1 hour, decreased at 6 hours, and increased at 12 hours. The uninjured side showed no significant pathological change at 1 hour after injury. Cytotoxic edema appeared at 3 hours, and vasogen-ic edema was visible at 6 hours. Cytotoxic edema persisted, but vasogenic edema tended to decrease after 12-24 hours. Despite this complex edema pattern on the uninjured side with associated pathologic changes, no significant change in apparent diffusion coefficient values was detected over the first 24 hours. Apparent diffusion coefficient values accurately detected the changes on the injured side, but did not detect the changes on the uninjured side, giving a false-negative result.

  18. THE EFFECT OF BODY WEIGHT OF PIGS ON TRUE AND APPARENT ILEAL AMINO ACIDS DIGESTIBILITY OF RYE

    Directory of Open Access Journals (Sweden)

    Nitrayová

    2013-02-01

    Full Text Available It is generally accepted that the ability of pigs to digest protein increases with age. However, it has been shown that small pigs excreted more endogenous nitrogen (N than large pigs. Consequently, the apparent amino acids (AA digestibility may be lower in young pigs while true digestibility, which is corrected for endogenous losses, may be comparable with that found in older pigs. To test this hypothesis, six cannulated piglets (mean body weight 20.6 kg fitted with a simple T-cannula at terminal ileum were used to estimate apparent and true digestibilities of AA and of total N in a rye-based diet (96 % rye. The digestibility study was repeated on the same pigs fed the same diet when they reached mean body weight 61.7 kg. The apparent ileal digestibilities of total AA and total N were significantly higher in heavier pigs than in piglets. Except for methionine and phenylalanine, the apparent digestibilities of individual AA showed a similar pattern. In contrast, there was no significant difference between piglets and heavier pigs for the true ileal digestibility of total N. True digestibility of most AA was lower in heavier pigs than in piglets, the differences for total and some individual AA being significant. The present results suggest that the higher apparent digestibility values found in heavier pigs as compared to piglets are due to the confounding effect of endogenous N losses rather than the better ability of older pigs to digest protein.

  19. Apparent temperature and acute myocardial infarction hospital admissions in Copenhagen, Denmark: a case-crossover study

    Directory of Open Access Journals (Sweden)

    Wichmann Janine

    2012-03-01

    Full Text Available Abstract Background The influence of temperature on acute myocardial infarction (AMI has not been investigated as extensively as the effects of broader outcomes of morbidity and mortality. Sixteen studies reported inconsistent results and two considered confounding by air pollution. We addressed some of the methodological limitations of the previous studies in this study. Methods This is the first study of the association between the daily 3-hour maximum apparent temperature (Tappmax and AMI hospital admissions in Copenhagen. The study period covered 1 January 1999-31 December 2006, stratified in warm (April - September and cold (October - March periods. A case-crossover epidemiology study design was applied. Models were adjusted for public holidays and influenza, confounding by PM10, NO2 and CO was investigated, the lag and non-linear effects of Tappmax was examined, effect modification by age, sex and SES was explored, and the results of the case-crossover models were compared to those of the generalised additive Poisson time-series and generalised estimating equation models. Results 14 456 AMI hospital admissions (12 995 people occurred during the study period. For an inter-quartile range (6 or 7°C increase in the 5-day cumulative average of Tappmax, a 4% (95% CI:-2%; 10% and 9% (95% CI: 3%; 14% decrease in the AMI admission rate was observed in the warm and cold periods, respectively. The 19-65 year old group, men and highest SES group seemed to be more susceptible in the cold period. Conclusion An increase in Tappmax is associated with a decrease in AMI admissions during the colder months.

  20. Apparent diffusion coefficient values of the normal uterus: Interindividual variations during menstrual cycle

    Energy Technology Data Exchange (ETDEWEB)

    Tsili, A.C., E-mail: a_tsili@yahoo.gr [Department of Clinical Radiology, University Hospital of Ioannina (Greece); Argyropoulou, M.I., E-mail: margyrop@cc.uoi.gr [Department of Clinical Radiology, University Hospital of Ioannina (Greece); Tzarouchi, L., E-mail: ltzar@cc.uoi.gr [Department of Clinical Radiology, University Hospital of Ioannina (Greece); Dalkalitsis, N., E-mail: ndalkal@cc.uoi.gr [Department of Obstetrics and Gynaecology, University Hospital of Ioannina (Greece); Koliopoulos, G., E-mail: georgekoliopoulos@yahoo.com [Department of Obstetrics and Gynaecology, University Hospital of Ioannina (Greece); Paraskevaidis, E., E-mail: eparaske@cc.uoi.gr [Department of Obstetrics and Gynaecology, University Hospital of Ioannina (Greece); Tsampoulas, K., E-mail: ctsampou@uoi.gr [Department of Clinical Radiology, University Hospital of Ioannina (Greece)

    2012-08-15

    Objectives: To assess the apparent diffusion coefficient (ADC) changes of the normal uterine zones among reproductive women during the menstrual cycle. Methods: The study included 101 women of reproductive age, each with regular cycle and normal endometrium/myometrium, as proved on histopathology or MR imaging examination. Diffusion-weighted (DW) imaging was performed along the axial plane, using a single shot, multi-slice spin-echo planar diffusion pulse sequence and b-values of 0 and 800 s/mm{sup 2}. The mean and standard deviation of the ADC values of normal endometrium/myometrium were calculated for menstrual, proliferative and secretory phase. Analysis of variance followed by the least significant difference test was used for statistical analysis. Results: The ADC values of the endometrium were different in the three phases of the menstrual cycle (menstrual phase: 1.25 {+-} 0.27; proliferative phase: 1.39 {+-} 0.20; secretory phase: 1.50 {+-} 0.18) (F: 9.64, p: 0.00). Statistical significant difference was observed among all groups (p < 0.05). The ADC values of the normal myometrium were different in the three phases of the menstrual cycle (menstrual phase: 1.91 {+-} 0.35; proliferative phase: 1.72 {+-} 0.27; secretory phase: 1.87 {+-} 0.28) (F: 3.60, p: 0.03). Statistical significant difference was observed between menstrual and proliferative phase and between proliferative and secretory phase (p < 0.05). No significant difference was noted between menstrual and secretory phase (p > 0.05). Conclusions: A wide variation of ADC values of normal endometrium and myometrium is observed during different phases of the menstrual cycle.

  1. Cretaceous Apparent Polar Wander Relative to the Major Cratons and Displacement Estimates of Baja British Columbia

    Science.gov (United States)

    Enkin, R. J.

    2004-12-01

    When paleogeographic interpretations derived from independent observations conflict, the methods and results from each discipline come under careful scrutiny, as illustrated by the Baja British Columbia controversy. Cretaceous paleomagnetic data from a large region of the Canadian Cordillera render paleopoles which are far-sided with respect to cratonic North American poles, suggesting this region, designated Baja British Columbia, translated northward during Late Cretaceous - Paleogene time. Criticism of this interpretation based on other geological reasoning prompted me to perform new reviews of Cretaceous to Eocene paleomagnetic results from the Cordillera and from the major cratons of the globe. The global review follows the method of Besse and Courtillot (1991; 2002). One difference between our methods is that I compiled paleomagnetic results from highly studied rock units to single results to balance data weightings spatially and temporally, thus reducing the number of individual results. For the period 160 to 40 Ma, 51 poles were included compared to 92 poles by Besse and Courtillot (2002). Differences between apparent polar wander paths in their and my analyses are never significant at 95% confidence, however mean pole positions differ by up to 500 km, which is important for paleogeographic analysis. The global distribution of sampling localities and the tight clustering of the paleomagnetic poles after plate reconstruction provide invaluable confirmation of plate tectonically derived Euler rotations, the reliability of paleomagnetic remanence directions, and the geocentric dipole geometry of the geomagnetic field. My Cordilleran review shows that paleolatitudes derived from plutons and remagnetized rocks are significantly more scattered than those derived from bedded rocks. Using bedded rocks only, the paleomagnetic record shows that Baja British Columbia sat 2100 ± 500 km south of its present position with respect to cratonic North America during the

  2. Brachial and lumbar plexuses in chronic inflammatory demyelinating polyradiculoneuropathy: MRI assessment including apparent diffusion coefficient

    Energy Technology Data Exchange (ETDEWEB)

    Adachi, Yuko; Sato, Noriko; Yamashita, Fumio; Kida, Jiro; Takahashi, Tomoyuki [National Center Hospital of Neurology and Psychiatry, Department of Radiology, Kodaira, Tokyo (Japan); Okamoto, Tomoko [National Center Hospital of Neurology and Psychiatry, Department of Neurology, Kodaira, Tokyo (Japan); Sasaki, Masayuki; Komaki, Hirofumi [National Center Hospital of Neurology and Psychiatry, Department of Child Neurology, Kodaira, Tokyo (Japan); Matsuda, Hiroshi [Saitama Medial University Hospital, Department of Nuclear Medicine, Iruma-gun, Saitama (Japan)

    2011-01-15

    Our purpose was to clarify the magnetic resonance (MR) imaging characteristics of the brachial and lumbar plexuses in patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) using various kinds of sequences, including diffusion-weighted images (DWI). We evaluated the MR imaging findings for lumbar and/or brachial nerve plexuses in 13 CIDP patients and 11 normal volunteers. The nerve swelling was evaluated in comparison with normal controls by coronal short tau inversion recovery (STIR), and signal abnormalities were evaluated by coronal STIR, T1-weighted images, and DWIs. The degrees of contrast enhancement and apparent diffusion coefficient (ADC) values of the plexus were also assessed. In the patient group, diffuse enlargement and abnormally high signals were detected in 16 out of 24 plexuses (66.7%) on STIR, a slightly high signal was detected in 12 of 24 plexuses (50%) on T1-weighted images, and a high-intensity signal was detected in 10 of 18 plexuses (55.6%) on DWIs with high ADC values. Contrast enhancement of the plexuses was revealed in 6 of 19 plexuses (31.6%) and was mild in all cases. There were statistically significant differences between the ADC values of patients with either swelling or abnormal signals and those of both normal volunteers and patients without neither swelling nor abnormal signals. There were no relationships between MR imaging and any clinical findings. STIR is sufficient to assist clinicians in diagnosing CIDP. T1-weighted images and DWIs seemed useful for speculating about the pathological changes in swollen plexuses in CIDP patients. (orig.)

  3. Apparent diffusion coefifcient values of normal testis and variations with age

    Institute of Scientific and Technical Information of China (English)

    Athina C Tsili; Dimitrios Giannakis; Anastasios Sylakos; Alexandra Ntorkou; Loukas G Astrakas; Nikolaos Soifkitis; Maria I Argyropoulou

    2014-01-01

    The usefulness of diffusion-weighted magnetic resonance imaging (DWI) in the evaluation of scrotal pathology has recently been reported. A standard reference of normal testicular apparent diffusion coefifcient (ADC) values and their variations with age is necessary when interpreting normal testicular anatomy and pathology. We evaluated 147 normal testes using DWI, including 71 testes from 53 men aged 20-39 years (group 1), 67 testes from 42 men aged 40-69 years (group 2) and nine testes from six men older than 70 years (group 3). DWI was performed along the axial plane, using a single shot, multislice spin-echo planar diffusion pulse sequence and b-values of 0 and 900 s mm-2. The mean and standard deviation of the ADC values of normal testicular parenchyma were calculated for each age group separately. Analysis of variance (ANOVA) followed by post hoc analysis (Dunnett T3) was used for statistical purposes. The ADC values (× 10-3 mm2 s-1) of normal testicular tissue were different among age groups (group 1:1.08 ± 0.13;group 2:1.15 ± 0.15 and group 3:1.31 ± 0.22). ANOVA revealed differences in mean ADC among age groups (F=11.391, P<0.001). Post hoc analysis showed differences between groups 1 and 2 (P=0.008) and between groups 1 and 3 (P=0.043), but not between groups 2 and 3 (P=0.197). Our ifndings suggest that ADC values of normal testicular tissue increase with advancing age.

  4. The role of apparent diffusion coefficient values in detecting testicular intraepithelial neoplasia: Preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Tsili, Athina C., E-mail: a_tsili@yahoo.gr [Department of Radiology, Medical School, University of Ioannina, 45110 Ioannina (Greece); Ntorkou, Alexandra, E-mail: alexdorkou@yahoo.com [Department of Radiology, Medical School, University of Ioannina, 45110 Ioannina (Greece); Baltogiannis, Dimitrios, E-mail: Greece.dbaltog@cc.uoi.gr [Department of Urology, Medical School, University of Ioannina, 45110 Ioannina (Greece); Goussia, Anna, E-mail: agoussia@uoi.gr [Department of Pathology, Medical School, University of Ioannina, 45110 Ioannina (Greece); Astrakas, Loukas G., E-mail: astrakas@uoi.gr [Department of Medical Physics, Medical School, University of Ioannina, 45110 Ioannina (Greece); Malamou-Mitsi, Vasiliki, E-mail: vmalamou@cc.uoi.gr [Department of Pathology, Medical School, University of Ioannina, 45110 Ioannina (Greece); Sofikitis, Nikolaos, E-mail: akrosnin@hotmail.com [Department of Urology, Medical School, University of Ioannina, 45110 Ioannina (Greece); Argyropoulou, Maria I., E-mail: margyrop@cc.uoi.gr [Department of Radiology, Medical School, University of Ioannina, 45110 Ioannina (Greece)

    2015-05-15

    Highlights: • ADC values proved useful in the discrimination between TGCNs and normal testis. • Testicular intraepithelial neoplasia represents the precursor of most TGCNs. • ADC values cannot be used to detect testicular intraepithelial neoplasia. - Abstract: Introduction: The aim of this study is to improve detection of testicular intraepithelial neoplasia (TIN) by measurement of apparent diffusion coefficient (ADC) values. Materials and methods: Fifty-six MRI examinations of the scrotum, including 26 histologically proven testicular germ cell neoplasms were retrospectively evaluated. DWI was performed using a single shot, multi-slice spin-echo planar diffusion pulse sequence and b-values of 0 and 900 s mm{sup −2}. ADC measurements were classified into three groups according to their location: group 1 (n = 19), non-tumoral part, adjacent to testicular carcinoma, where the possible location of TIN was; group 2 (n = 26), testicular carcinoma; and group 3 (n = 60), normal testicular parenchyma. Analysis of variance (ANOVA) followed by post hoc analysis (Dunnett T3) was used for statistical purposes. Results: The mean ± s.d. of ADC values (×10{sup −3} mm{sup 2}/s) of different groups were: group 1, 1.08 ± 0.20; group 2, 0.72 ± 0.27; and group 3, 1.11 ± 0.14. ANOVA revealed differences of mean ADC between groups (F = 38.859, P < 0.001). Post hoc analysis showed differences between groups 2 and 3 (P < 0.001), groups 2 and 1 (P < 0.001), but not between groups 3 and 1 (P = 0.87). Conclusions: Based on our preliminary results, ADC values do not provide a reliable differentiation between TIN and testicular carcinoma or normal testicular parenchyma.

  5. Reconciling apparent conflicts between mitochondrial and nuclear phylogenies in African elephants.

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    Yasuko Ishida

    Full Text Available Conservation strategies for African elephants would be advanced by resolution of conflicting claims that they comprise one, two, three or four taxonomic groups, and by development of genetic markers that establish more incisively the provenance of confiscated ivory. We addressed these related issues by genotyping 555 elephants from across Africa with microsatellite markers, developing a method to identify those loci most effective at geographic assignment of elephants (or their ivory, and conducting novel analyses of continent-wide datasets of mitochondrial DNA. Results showed that nuclear genetic diversity was partitioned into two clusters, corresponding to African forest elephants (99.5% Cluster-1 and African savanna elephants (99.4% Cluster-2. Hybrid individuals were rare. In a comparison of basal forest "F" and savanna "S" mtDNA clade distributions to nuclear DNA partitions, forest elephant nuclear genotypes occurred only in populations in which S clade mtDNA was absent, suggesting that nuclear partitioning corresponds to the presence or absence of S clade mtDNA. We reanalyzed African elephant mtDNA sequences from 81 locales spanning the continent and discovered that S clade mtDNA was completely absent among elephants at all 30 sampled tropical forest locales. The distribution of savanna nuclear DNA and S clade mtDNA corresponded closely to range boundaries traditionally ascribed to the savanna elephant species based on habitat and morphology. Further, a reanalysis of nuclear genetic assignment results suggested that West African elephants do not comprise a distinct third species. Finally, we show that some DNA markers will be more useful than others for determining the geographic origins of illegal ivory. These findings resolve the apparent incongruence between mtDNA and nuclear genetic patterns that has confounded the taxonomy of African elephants, affirm the limitations of using mtDNA patterns to infer elephant systematics or population

  6. Reconciling apparent conflicts between mitochondrial and nuclear phylogenies in African elephants.

    Science.gov (United States)

    Ishida, Yasuko; Oleksyk, Taras K; Georgiadis, Nicholas J; David, Victor A; Zhao, Kai; Stephens, Robert M; Kolokotronis, Sergios-Orestis; Roca, Alfred L

    2011-01-01

    Conservation strategies for African elephants would be advanced by resolution of conflicting claims that they comprise one, two, three or four taxonomic groups, and by development of genetic markers that establish more incisively the provenance of confiscated ivory. We addressed these related issues by genotyping 555 elephants from across Africa with microsatellite markers, developing a method to identify those loci most effective at geographic assignment of elephants (or their ivory), and conducting novel analyses of continent-wide datasets of mitochondrial DNA. Results showed that nuclear genetic diversity was partitioned into two clusters, corresponding to African forest elephants (99.5% Cluster-1) and African savanna elephants (99.4% Cluster-2). Hybrid individuals were rare. In a comparison of basal forest "F" and savanna "S" mtDNA clade distributions to nuclear DNA partitions, forest elephant nuclear genotypes occurred only in populations in which S clade mtDNA was absent, suggesting that nuclear partitioning corresponds to the presence or absence of S clade mtDNA. We reanalyzed African elephant mtDNA sequences from 81 locales spanning the continent and discovered that S clade mtDNA was completely absent among elephants at all 30 sampled tropical forest locales. The distribution of savanna nuclear DNA and S clade mtDNA corresponded closely to range boundaries traditionally ascribed to the savanna elephant species based on habitat and morphology. Further, a reanalysis of nuclear genetic assignment results suggested that West African elephants do not comprise a distinct third species. Finally, we show that some DNA markers will be more useful than others for determining the geographic origins of illegal ivory. These findings resolve the apparent incongruence between mtDNA and nuclear genetic patterns that has confounded the taxonomy of African elephants, affirm the limitations of using mtDNA patterns to infer elephant systematics or population structure, and

  7. Hydrogen apparent fractionation between source water and epicuticular waxes of Pinus sylvestris in North East Finland

    Science.gov (United States)

    Newberry, S. L.; Grace, J.; Pedentchouk, N.

    2010-12-01

    Hydrogen isotopic composition of plant biomass provides crucial information about plant ecophysiology and local hydrology. Little is known about the apparent fractionation between hydrogen in source water and epicuticular leaf waxes of coniferous tree species that dominate the boreal forest ecosystem exposed to prolonged periods of sunlight during the growing season. In this study, single rope canopy access techniques were used to harvest needle and twig material from the upper, middle and lower crown of north and south facing branches of Pinus sylvestris within the subarctic forest of North East Finland. Samples were collected towards the beginning of the growing season in July and repeated in late September 2010. Leaf and twig waters were extracted cryogenically and analysed for D-enrichment. Individual n-alkanes are currently being quantified and analyzed for 13C/12C and D/H compositions. The molecular and isotopic data are supplemented by long-term in-situ cuvette photosynthetic assimilation measurements as well as relative humidity (RH), air temperature, precipitation and wind speed data collected by Helsinki University (SMEAR I). In addition RH, air temperature, wind speed and incoming solar radiation measurements were made at each individual sample point at the time of harvesting to quantify meteorological and microclimatological variation within individual trees. The outcome of this investigation will provide important insights into plant biochemistry and physiology of a crucial climate sensitive higher plant species subjected to continuous low light throughout the season. Furthermore, this work will expand our understanding of modern and palaeo-hydrology not only in northern Finland but also in other boreal forests around the world.

  8. Apparent diffusion coefficient in glioblastoma with PNET-like components, a GBM variant.

    Science.gov (United States)

    Ali, Saad; Joseph, Nancy M; Perry, Arie; Barajas, Ramon F; Cha, Soonmee

    2014-09-01

    Glioblastoma (GBM) with primitive neuroectodermal tumor (PNET)-like (GBM-PNET) components is a rare variant of GBM. Recent studies describe PNET-like clinical behavior in these patients-with significantly increased propensity for CSF dissemination and a benefit of "PNET-like" chemotherapy. The imaging appearance of GBM-PNET is not well-described and given areas of marked cellularity in the PNET components one might expect significantly reduced diffusion on MRI. The purpose of this study is to quantitatively evaluate the diffusion characteristics in GBM-PNET and compare them with conventional GBMs. Nine patients with surgical specimens yielding GBM-PNET were identified from the UCSF Pathology files. MR images of these patients were reviewed retrospectively. DWI (diffusion-weighted imaging) sequences were analyzed with multiple regions of interests placed within the tumor, and ADC (apparent diffusion coefficient) values were measured. Results were compared to previously published ADC values in pathology-proven conventional GBM cases from our institution. Reduced ADC was seen in GBM-PNET (mean 581 × 10(-6) mm(2)/s, range 338-817) compared to previously published mean of 1,030 × 10(-6) mm(2)/s in the enhancing components of conventional GBMs. We report substantially reduced ADC values in GBM-PNETs compared to conventional GBMs. If demonstrated in a larger sample, when areas of marked reduced diffusion are seen in a suspected GBM, MRI may appropriately direct tissue sampling and can advocate a thorough search for PNET-like components on histopathology. These patients may have a higher chance of developing CSF dissemination and may benefit from "PNET-like" platinum-based chemotherapy.

  9. Gone or just out of sight? The apparent disappearance of aromatic litter components in soils

    Science.gov (United States)

    Klotzbücher, Thimo; Kalbitz, Karsten; Cerli, Chiara; Hernes, Peter J.; Kaiser, Klaus

    2016-07-01

    Uncertainties concerning stabilization of organic compounds in soil limit our basic understanding on soil organic matter (SOM) formation and our ability to model and manage effects of global change on SOM stocks. One controversially debated aspect is the contribution of aromatic litter components, such as lignin and tannins, to stable SOM forms. In the present opinion paper, we summarize and discuss the inconsistencies and propose research options to clear them. Lignin degradation takes place stepwise, starting with (i) depolymerization and followed by (ii) transformation of the water-soluble depolymerization products. The long-term fate of the depolymerization products and other soluble aromatics, e.g., tannins, in the mineral soils is still a mystery. Research on dissolved organic matter (DOM) composition and fluxes indicates dissolved aromatics are important precursors of stable SOM attached to mineral surfaces and persist in soils for centuries to millennia. Evidence comes from flux analyses in soil profiles, biodegradation assays, and sorption experiments. In contrast, studies on composition of mineral-associated SOM indicate the prevalence of non-aromatic microbial-derived compounds. Other studies suggest the turnover of lignin in soil can be faster than the turnover of bulk SOM. Mechanisms that can explain the apparent fast disappearance of lignin in mineral soils are, however, not yet identified. The contradictions might be explained by analytical problems. Commonly used methods probably detect only a fraction of the aromatics stored in the mineral soil. Careful data interpretation, critical assessment of analytical limitations, and combined studies on DOM and solid-phase SOM could thus be ways to unveil the issues.

  10. Effect of virginiamycin on the apparent ileal digestibility of amino acids by growing pigs.

    Science.gov (United States)

    Stewart, L L; Kim, B G; Gramm, B R; Nimmo, R D; Stein, H H

    2010-05-01

    The objective of this experiment was to measure the influence of virginiamycin on the apparent ileal digestibility (AID) of AA by growing pigs. Fifteen barrows were surgically equipped with a T-cannula in the distal ileum and used in the experiment (initial BW = 35.0 +/- 2.7 kg). Animals were randomly allotted to 3 dietary treatments with 5 pigs per treatment during a 6-wk experiment. Dietary treatments included 1) a basal corn-soybean meal diet, 2) the basal diet supplemented with 11 mg/kg of virginiamycin, and 3) the basal diet supplemented with 22 mg/kg of virginiamycin. Pigs were fed their respective treatment diets during wk 2, 3, and 4, but during wk 1, 5, and 6, all pigs were fed the basal diet. Ileal samples were collected on d 6 and 7 of each week. Results showed that the AID of all indispensable AA, except Arg, His, and Ile, increased (P virginiamycin. Pigs fed 22 mg/kg of virginiamycin during wk 2, 3, and 4 had increased (P virginiamycin was withdrawn from the diet, regardless of the inclusion rate. In pooled data from wk 2, 3, and 4, the AID of CP, the mean of all indispensable AA, and Ile, Leu, Met, Phe, Trp, and Val increased (linear, P virginiamycin was added to the diets, whereas a tendency (P virginiamycin to corn-soybean meal diets fed to growing pigs increases the AID of AA, but this effect is not maintained after the removal of virginiamycin from the diet.

  11. Impact of cannibalism on predator-prey dynamics: size-structured interactions and apparent mutualism.

    Science.gov (United States)

    Rudolf, Volker H W

    2008-06-01

    Direct and indirect interactions between two prey species can strongly alter the dynamics of predator-prey systems. Most predators are cannibalistic, and as a consequence, even systems with only one predator and one prey include two prey types: conspecifics and heterospecifics. The effects of the complex direct and indirect interactions that emerge in such cannibalistic systems are still poorly understood. This study examined how the indirect interaction between conspecific and heterospecific prey affects cannibalism and predation rates and how the direct interactions between both species indirectly alter the effect of the cannibalistic predator. I tested for these effects using larvae of the stream salamanders Eurycea cirrigera (prey) and Pseudotriton ruber (cannibalistic predator) by manipulating the relative densities of the conspecific and heterospecific prey in the presence and absence of the predator in experimental streams. The rates of cannibalism and heterospecific predation were proportional to the respective densities and negatively correlated, indicating a positive indirect interaction between conspecific and heterospecific prey, similar to "apparent mutualism." Direct interactions between prey species did not alter the effect of the predator. Although both types of prey showed a similar 30% reduction in night activity and switch in microhabitat use in response to the presence of the predator, cannibalism rates were three times higher than heterospecific predation rates irrespective of the relative densities of the two types of prey. Cumulative predation risks differed even more due to the 48% lower growth rate of conspecific prey. Detailed laboratory experiments suggest that the 3:1 difference in cannibalism and predation rate was due to the higher efficiency of heterospecific prey in escaping immediate attacks. However, no difference was observed when the predator was a closely related salamander species, Gyrinophilus porphyriticus, indicating that

  12. Inferring inherent optical properties and water constituent profiles from apparent optical properties.

    Science.gov (United States)

    Fan, Yongzhen; Li, Wei; Calzado, Violeta Sanjuan; Trees, Charles; Stamnes, Snorre; Fournier, Georges; McKee, David; Stamnes, Knut

    2015-07-27

    The BP09 experiment conducted by the Centre for Maritime Research and Experimentation in the Ligurian Sea in March 2009 provided paired vertical profiles of nadir-viewing radiances L(u)(z) and downward irradiances E(d)(z) and inherent optical properties (IOPs, absorption, scattering and backscattering coefficients). An inversion algorithm was implemented to retrieve IOPs from apparent optical properties (AOPs, radiance reflectance R(L), irradiance reflectance R(E) and diffuse attenuation coefficient K(d)) derived from the radiometric measurements. Then another inversion algorithm was developed to infer vertical profiles of water constituent concentrations, including chlorophyll-a concentration, non-algal particle concentration, and colored dissolved organic matter from the retrieved IOPs based on a bio-optical model. The algorithm was tested on a synthetic dataset and found to give reliable results with an accuracy better than 1%. When the algorithm was applied to the BP09 dataset it was found that good retrievals of IOPs could be obtained for sufficiently deep waters, i.e. for L(u)(z) and E(d)(z) measurements conducted to depths of 50 m or more. This requirement needs to be satisfied in order to obtain a good estimation of the backscattering coefficient. For such radiometric measurements a correlation of 0.88, 0.96 and 0.93 was found between retrieved and measured absorption, scattering and backscattering coefficients, respectively. A comparison between water constituent values derived from the measured IOPs and in-situ measured values, yielded a correlation of 0.80, 0.78, and 0.73 for chlorophyll-a concentration, non-algal particle concentration, and absorption coefficient of colored dissolved organic matter at 443 nm, respectively. This comparison indicates that adjustments to the bio-optical model are needed in order to obtain a better match between inferred and measured water constituent values in the Ligurian Sea using the methodology developed in this paper.

  13. Comparison of body composition between professional sportswomen and apparently healthy age- and sex-matched controls

    Directory of Open Access Journals (Sweden)

    Raman K Marwaha

    2015-01-01

    Full Text Available Introduction: In view of the relationship between physical activity and nutrition on body composition, we assessed lean and fat mass and BMC (total and regional in professional Indian sportswomen and compared it with apparently healthy age- and sex-matched females. Materials and Methods: This cross-sectional study included 104 sportswomen and an equal number of age-matched normal healthy females (controls. They were evaluated for anthropometry and body composition (fat, lean mass, and bone mineral content (BMC by DXA. Results: Mean age (19.1 ± 1.3 vs. 19.4 ± 1.5 years and body mass index (21.34 ± 3.02 vs. 21.26 ± 4.05 kg/m 2 were comparable in both groups. Sportswomen had higher intake of energy, macronutrients, calcium, phosphorus and magnesium. Total lean mass (33.67 ± 3.49 vs. 31.14 ± 3.52 kg, P < 0.0001, appendicular skeletal muscle index (5.84 ± 0.57 vs. 5.46 ± 0.63 kg/m 2 ; P < 0.0001 and BMC (2.27 ± 0.32 vs. 2.13 ± 0.34 kg, P < 0.002 was significantly higher and percentage fat mass was significantly lower (33.1 ± 7.5 vs. 37.0 ± 8.3; P < 0.0001 among sportswomen when compared to controls. Conclusions: Indian sportswomen have a higher total and regional lean mass, BMC, and lower percentage fat mass when compared with healthy females. Physical activity, energy, protein and calcium intake were positively associated with lean mass and BMC.

  14. Apparent diffusion coefficient values of normal testis and variations with age

    Directory of Open Access Journals (Sweden)

    Athina C Tsili

    2014-06-01

    Full Text Available The usefulness of diffusion-weighted magnetic resonance imaging (DWI in the evaluation of scrotal pathology has recently been reported. A standard reference of normal testicular apparent diffusion coefficient (ADC values and their variations with age is necessary when interpreting normal testicular anatomy and pathology. We evaluated 147 normal testes using DWI, including 71 testes from 53 men aged 20-39 years (group 1, 67 testes from 42 men aged 40-69 years (group 2 and nine testes from six men older than 70 years (group 3. DWI was performed along the axial plane, using a single shot, multislice spin-echo planar diffusion pulse sequence and b-values of 0 and 900 s mm−2 . The mean and standard deviation of the ADC values of normal testicular parenchyma were calculated for each age group separately. Analysis of variance (ANOVA followed by post hoc analysis (Dunnett T3 was used for statistical purposes. The ADC values (× 10−3 mm 2 s−1 of normal testicular tissue were different among age groups (group 1: 1.08 ± 0.13; group 2: 1.15 ± 0.15 and group 3: 1.31 ± 0.22. ANOVA revealed differences in mean ADC among age groups (F = 11.391, P < 0.001. Post hoc analysis showed differences between groups 1 and 2 (P = 0.008 and between groups 1 and 3 (P = 0.043, but not between groups 2 and 3 (P = 0.197. Our findings suggest that ADC values of normal testicular tissue increase with advancing age.

  15. Are we predicting the actual or apparent distribution of temperate marine fishes?

    Directory of Open Access Journals (Sweden)

    Jacquomo Monk

    Full Text Available Planning for resilience is the focus of many marine conservation programs and initiatives. These efforts aim to inform conservation strategies for marine regions to ensure they have inbuilt capacity to retain biological diversity and ecological function in the face of global environmental change--particularly changes in climate and resource exploitation. In the absence of direct biological and ecological information for many marine species, scientists are increasingly using spatially-explicit, predictive-modeling approaches. Through the improved access to multibeam sonar and underwater video technology these models provide spatial predictions of the most suitable regions for an organism at resolutions previously not possible. However, sensible-looking, well-performing models can provide very different predictions of distribution depending on which occurrence dataset is used. To examine this, we construct species distribution models for nine temperate marine sedentary fishes for a 25.7 km(2 study region off the coast of southeastern Australia. We use generalized linear model (GLM, generalized additive model (GAM and maximum entropy (MAXENT to build models based on co-located occurrence datasets derived from two underwater video methods (i.e. baited and towed video and fine-scale multibeam sonar based seafloor habitat variables. Overall, this study found that the choice of modeling approach did not considerably influence the prediction of distributions based on the same occurrence dataset. However, greater dissimilarity between model predictions was observed across the nine fish taxa when the two occurrence datasets were compared (relative to models based on the same dataset. Based on these results it is difficult to draw any general trends in regards to which video method provides more reliable occurrence datasets. Nonetheless, we suggest predictions reflecting the species apparent distribution (i.e. a combination of species distribution and the

  16. Associations of amylin with inflammatory markers and metabolic syndrome in apparently healthy Chinese.

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    Xinwei Hou

    Full Text Available BACKGROUND: Cellular and animal studies implicate multiple roles of amylin in regulating insulin action, glucose and lipid metabolisms. However, the role of amylin in obesity related metabolic disorders has not been thoroughly investigated in humans. Therefore, we aimed to evaluate the distribution of circulating amylin and its association with metabolic syndrome (MetS and explore if this association is influenced by obesity, inflammatory markers or insulin resistance in apparently healthy Chinese. METHODS: A population-based sample of 1,011 Chinese men and women aged 35-54 years was employed to measure plasma amylin, inflammatory markers (C-reactive protein [CRP] and interleukin-6 [IL-6], insulin, glucose and lipid profiles. MetS was defined according to the updated National Cholesterol Education Program Adult Treatment Panel III criteria for Asian-Americans. RESULTS: Plasma amylin concentrations were higher in overweight/obese participants than normal-weight counterparts (P<0.001 without sex difference. Circulating amylin was positively associated with CRP, IL-6, BMI, waist circumference, blood pressure, fasting glucose, insulin, amylin/insulin ratio, HOMA-IR, LDL cholesterol and triglycerides, while negatively associated with HDL cholesterol (all P<0.001. After multiple adjustments, the risk of MetS was significantly higher (odds ratio 3.71; 95% confidence interval: 2.53 to 5.46 comparing the highest with the lowest amylin quartile. The association remained significant even further controlling for BMI, inflammatory markers, insulin or HOMA-IR. CONCLUSIONS: Our study suggests that amylin is strongly associated with inflammatory markers and MetS. The amylin-MetS association is independent of established risk factors of MetS, including obesity, inflammatory markers and insulin resistance. The causal role of hyperamylinemia in the development of MetS needs to be confirmed prospectively.

  17. Apparent optical properties of the Canadian Beaufort Sea - Part 1: Observational overview and water column relationships

    Science.gov (United States)

    Antoine, D.; Hooker, S. B.; Bélanger, S.; Matsuoka, A.; Babin, M.

    2013-07-01

    A data set of radiometric measurements collected in the Beaufort Sea (Canadian Arctic) in August 2009 (Malina project) is analyzed in order to describe apparent optical properties (AOPs) in this sea, which has been subject to dramatic environmental changes for several decades. The two properties derived from the measurements are the spectral diffuse attenuation coefficient for downward irradiance, Kd, and the spectral remote sensing reflectance, Rrs. The former controls light propagation in the upper water column. The latter determines how light is backscattered out of the water and becomes eventually observable from a satellite ocean color sensor. The data set includes offshore clear waters of the Beaufort Basin as well as highly turbid waters of the Mackenzie River plumes. In the clear waters, we show Kd values that are much larger in the ultraviolet and blue parts of the spectrum than what could be anticipated considering the chlorophyll concentration. A larger contribution of absorption by colored dissolved organic matter (CDOM) is responsible for these high Kd values, as compared to other oligotrophic areas. In turbid waters, attenuation reaches extremely high values, driven by high loads of particulate materials and also by a large CDOM content. In these two extreme types of waters, current satellite chlorophyll algorithms fail. This questions the role of ocean color remote sensing in the Arctic when Rrs from only the blue and green bands are used. Therefore, other parts of the spectrum (e.g., the red) should be explored if one aims at quantifying interannual changes in chlorophyll in the Arctic from space. The very peculiar AOPs in the Beaufort Sea also advocate for developing specific light propagation models when attempting to predict light availability for photosynthesis at depth.

  18. Apparent mesonephric duct (rete anlage) origin for cysts and proliferative epithelial lesions in the mouse ovary.

    Science.gov (United States)

    Long, Gerald G

    2002-01-01

    Ovaries and adjacent parovarian (mesovarial) tissues of CD-1 mice of various ages were examined to characterize cystic and proliferative epithelial lesions of the ovary and parovarian tissues. Ovaries and adjacent tissues from 6 mice each at approximately 3 and 8 months of age were processed for light microscopy and step-sections (50-micron intervals) of the entire tissue were examined. Tissues were collected from 40 mice each at 16 through 24 months of age and 3 step sections per mouse were examined. Mesonephric duct remnants were found in all mice at 3 and 8 months. Ducts were usually in the mesovarial adipose tissue and near or within the ovarian hilus and were often loosely associated with smooth muscle of the mesovarial ligament. The epithelium of the ducts varied from low cuboidal to columnar, occasional individual cells were ciliated, and small papillary configurations of epithelium were occasionally present. Ducts were dilated (> 1 mm) more often in mice at 8 months compared to 3 months, and some were continuous with cystic spaces within the ovaries. As mice aged (16-24 months), dilation and cystic change in ducts and associated compression of ovarian tissue away from the ovarian hilus became common. The epithelium of dilated ducts was generally flattened, but foci of cuboidal to columnar epithelium and/or occasional ciliated cells were present. Many ducts contained foci of hyperplastic and/or hypertrophic epithelium, and papillary projections of epithelium were occasionally found. Some of the latter lesions were consistent with a diagnosis of papillary cystadenoma. Hyperplasia of associated fibromuscular stroma was limited to a few apparently extraovarian ducts. The results of this study indicate that remnant mesonephric ductular structures are common in and adjacent to the ovaries of CD-1 mice. As mice age, these ducts become dilated and, in some, the epithelium becomes hyperplastic and/or hyperptrophic. These mesonephric duct remnants appear to be a

  19. Light Propagation Volumes

    OpenAIRE

    Mikulica, Tomáš

    2016-01-01

    Cílem diplomové práce je popsat různé metody výpočtu globálního osvětlení scény včetně techniky Light Propagation Volumes. Pro tuto metodu jsou podrobně popsány všechny tři kroky výpočtu: injekce, propagace a vykreslení. Dále je navrženo několik vlastních rozšíření zlepšující grafickou kvalitu metody. Části návrhu a implementace jsou zaměřeny na popis scény, zobrazovacího systému, tvorby stínů, implementace metody Light Propagation Volumes a navržených rozšíření. Práci uzavírá měření, porovná...

  20. Influence of the apparent molecular size of aquatic humic substances on colour removal by coagulation and filtration.

    Science.gov (United States)

    Rigobello, Eliane Sloboda; Dantas, Angela Di Bernardo; Di Bernardo, Luiz; Vieira, Eny Maria

    2011-12-01

    This study aims to verify the influence of the apparent molecular size of aquatic humic substances (AHSs) on the effectiveness of coagulation with aluminium sulphate and ferric chloride. Coagulation-filtration tests using the jar test and bench-scale sand filters were carried out with water samples having a true colour of approximately 100 Hazen units and prepared with AHSs of different molecular sizes. Stability diagrams are presented showing regions of > or = 90% and > or = 95% apparent colour removal delineated for each water sample using plots of total metal ion concentration (Al3+ and Fe3+) versus coagulation pH. To achieve the same degree of colour removal, the water samples with smaller apparent molecular sizes and a higher percentage of fulvic acids required higher dosages of both aluminium sulphate and ferric chloride.

  1. Pietro Manni (1778-1839) and the care of the apparently dead in the Age of Positivism.

    Science.gov (United States)

    Cascella, Marco

    2016-08-01

    When can a man be declared 'really dead'? Being able to determine whether an individual's life has ended or not implies two important considerations, whether we can resuscitate him and avoid premature burial, the fear of which is termed 'taphophobia'. By the end of the 18th century, several scientists were involved in the study of apparent death and resuscitation. Pietro Manni was an obstetrician who, affected by his brother's death and his inability to help him, devoted himself to the study of apparent death, which became his aim in life. His Practical handbook for the care of the apparently dead is a detailed essay on resuscitation with a precise arrangement of topics - ventilation, tracheostomy, electricity and asphyxia in newborns - organised into chapters and paragraphs that resemble current texts on resuscitation.

  2. Apparent activation energy for densification of -Al2O3 powder at constant heating-rate sintering

    Indian Academy of Sciences (India)

    W Q Shao; S O Chen; D Li; H S Cao; Y C Zhang; S S Zhang

    2008-11-01

    The apparent activation energy for densification is a characteristic quantity that elucidates the fundamental diffusion mechanisms during the sintering process. Based on the Arrhenius theory, the activation energy for densification of -Al2O3 at constant heating-rates sintering has been estimated. Sintering of -Al2O3 powder has been executed by the way of a push rod type dilatometer. It is shown that the apparent activation energy does not have a single value but depends directly on the relative density. The apparent activation energy corresponding to lower relative density was higher than that corresponding to higher relative density. In addition, the value of the evaluated activation energy is different at the same density level when the Arrhenius plot involves different heating rates.

  3. Apparent survival rates of forest birds in eastern Ecuador revisited: improvement in precision but no change in estimates.

    Directory of Open Access Journals (Sweden)

    John G Blake

    Full Text Available Knowledge of survival rates of Neotropical landbirds remains limited, with estimates of apparent survival available from relatively few sites and species. Previously, capture-mark-recapture models were used to estimate apparent survival of 31 species (30 passerines, 1 Trochilidae from eastern Ecuador based on data collected from 2001 to 2006. Here, estimates are updated with data from 2001-2012 to determine how additional years of data affect estimates; estimates for six additional species are provided. Models assuming constant survival had highest support for 19 of 31 species when based on 12 years of data compared to 27 when based on six; models incorporating effects of transients had the highest support for 12 of 31 species compared to four when based on 12 and six years, respectively. Average apparent survival based on the most highly-supported model (based on model averaging, when appropriate was 0.59 (± 0.02 SE across 30 species of passerines when based on 12 years and 0.57 (± 0.02 when based on six. Standard errors of survival estimates based on 12 years were approximately half those based on six years. Of 31 species in both data sets, estimates of apparent survival were somewhat lower for 13, somewhat higher for 17, and remained unchanged for one; confidence intervals for estimates based on six and 12 years of data overlapped for all species. Results indicate that estimates of apparent survival are comparable but more precise when based on longer-term data sets; standard error of the estimates was negatively correlated with numbers of captures (rs  = -0.72 and recaptures (rs  = -0.93, P<0.001 in both cases. Thus, reasonable estimates of apparent survival may be obtained with relatively few years of data if sample sizes are sufficient.

  4. Temporal stability of the apparent electrical conductivity measured in seasonally dry sandy soil

    Science.gov (United States)

    Pedrera, Aura; Brevik, Eric C.; Giráldez, Juan V.; Vanderlinden, Karl

    2016-04-01

    Soil is spatially heterogeneous due to differences in parent material, climate, topography, time and management practices. The use of non-invasive and non-contact geophysical methods facilitates the exploration of natural landscapes or cropped areas. Electromagnetic induction (EMI) sensors which measure the soil apparent electrical conductivity (ECa) express soil spatial variability in terms of spatial soil ECa variability. In an agricultural context, knowledge and understanding of the soil spatial variability will allow us to delimit areas where precision agriculture techniques could be used to improve management practices. These practices enhance soil and water conservation, especially for sandy soils in Mediterranean climates where soils are dry for substantial periods of time. The first objective of this work was to apply principal component analysis (PCA) to see if a temporally stable component could be found. The second objective was to see if temporal stability information acquired from several ECa surveys could be used to better interpret results of a single survey in terms of relationships between ECa and soil water content (SWC). The experimental catchment, "La Manga", is located in SW Spain and covers 6.7 ha of a rainfed olive orchard. Soil profile samples were collected at 41 locations on a pseudo-regular grid. Samples were analyzed in the laboratory for soil texture, stone content, and bulk density (ρb). The catchment was sampled for gravimetric SWC at the 0-0.1 and 0.1-0.2 m depth intervals at the same 41 locations on 18 occasions. At the same 41 locations ECa was measured during 9 of the 18 SWC surveys using a DUALEM-21S EMI sensor. In addition, 7 field-wide ECa surveys were conducted. Soil ECa values were used to delimit three areas in the orchard, based on the spatial distribution of the first principal component (PC), which represented the spatial ECa pattern. Soil properties were studied within each area, and using analysis of variance

  5. Apparent diffusion coefficient histogram analysis of neonatal hypoxic-ischemic encephalopathy

    Energy Technology Data Exchange (ETDEWEB)

    Cauley, Keith A. [University of Massachusetts Medical School, Department of Radiology, Worcester, MA (United States); New York Presbyterian Hospital, Columbia University Medical Center, Department of Radiology, New York, NY (United States); Filippi, Christopher G. [New York Presbyterian Hospital, Columbia University Medical Center, Department of Radiology, New York, NY (United States)

    2014-06-15

    Diffusion-weighted imaging is a valuable tool in the assessment of the neonatal brain, and changes in diffusion are seen in normal development as well as in pathological states such as hypoxic-ischemic encephalopathy (HIE). Various methods of quantitative assessment of diffusion values have been reported. Global ischemic injury occurring during the time of rapid developmental changes in brain myelination can complicate the imaging diagnosis of neonatal HIE. To compare a quantitative method of histographic analysis of brain apparent coefficient (ADC) maps to the qualitative interpretation of routine brain MR imaging studies. We correlate changes in diffusion values with gestational age in radiographically normal neonates, and we investigate the sensitivity of the method as a quantitative measure of hypoxic-ischemic encephalopathy. We reviewed all brain MRI studies from the neonatal intensive care unit (NICU) at our university medical center over a 4-year period to identify cases that were radiographically normal (23 cases) and those with diffuse, global hypoxic-ischemic encephalopathy (12 cases). We histographically displayed ADC values of a single brain slice at the level of the basal ganglia and correlated peak (s-sD{sub av}) and lowest histogram values (s-sD{sub lowest}) with gestational age. Normative s-sD{sub av} values correlated significantly with gestational age and declined linearly through the neonatal period (r {sup 2} = 0.477, P < 0.01). Six of 12 cases of known HIE demonstrated significantly lower s-sD{sub av} and s-sD{sub lowest} ADC values than were reflected in the normative distribution; several cases of HIE fell within a 95% confidence interval for normative studies, and one case demonstrated higher-than-normal s-sD{sub av}. Single-slice histographic display of ADC values is a rapid and clinically feasible method of quantitative analysis of diffusion. In this study normative values derived from consecutive neonates without radiographic evidence of

  6. Particle length of silages affects apparent ruminal synthesis of B vitamins in lactating dairy cows.

    Science.gov (United States)

    Castagnino, D S; Kammes, K L; Allen, M S; Gervais, R; Chouinard, P Y; Girard, C L

    2016-08-01

    Effects of particle length of silages on apparent ruminal synthesis (ARS) and postruminal supply of B vitamins were evaluated in 2 feeding trials. Diets containing alfalfa (trial 1) or orchardgrass (trial 2) silages, chopped to either 19mm (long cut, LC) or 10mm (short cut, SC) theoretical particle length, as the sole forage were offered to ruminally and duodenally cannulated lactating Holstein cows in crossover design experiments. Forages chopped to a theoretical particle length of 19 and 10mm had mean particles sizes of 14.1 and 8.1mm, respectively, in trial 1, and 15.3 and 11.3mm, respectively, in trial 2. Trial 1 was conducted with 13 multiparous cows in two 19-d treatment periods; both diets contained approximately 20% forage neutral detergent fiber (NDF), 25% total NDF, and forage-to-concentrate ratios were approximately 47:53. Trial 2 was conducted with 15 cows in two 18-d treatment periods; both diets contained approximately 23% forage NDF, 28% total NDF, and had a forage-to-concentrate ratio of 50:50. Thiamine, riboflavin, niacin, vitamin B6, folates, and vitamin B12 were measured in feed and duodenal content. Daily ARS was calculated as the duodenal flow minus the intake. In trial 1, daily intake of individual B vitamins was increased with the LC diet, but ARS of thiamine, riboflavin, vitamin B6, and folates was reduced. In trial 2, except for folates, intakes of the other B vitamins were decreased with the LC diets, whereas ARS of riboflavin, niacin, and vitamin B6 was increased. Daily ARS of thiamine, riboflavin, niacin, and vitamin B6 were correlated negatively with their intake, suggesting that ruminal bacteria reduced their synthesis when dietary supply increased. Microbial activity could have also reduced degradation of thiamine, riboflavin, and niacin, which is supported by (1) the negative correlation between ARS of these vitamins and ruminal pH or microbial N duodenal flow; and (2) the positive correlation between ARS and ruminal concentrations

  7. Apparent diffusion coefficient values and dynamic contrast enhancement patterns in differentiating seminomas from nonseminomatous testicular neoplasms

    Energy Technology Data Exchange (ETDEWEB)

    Tsili, Athina C., E-mail: a_tsili@yahoo.gr [Department of Radiology, Medical School, University of Ioannina, 45110 Ioannina (Greece); Sylakos, Anastasios, E-mail: anasylakos@yahoo.gr [Department of Urology, Medical School, University of Ioannina, 45110 Ioannina (Greece); Ntorkou, Alexandra, E-mail: alexdorkou@yahoo.com [Department of Radiology, Medical School, University of Ioannina, 45110 Ioannina (Greece); Stavrou, Sotirios, E-mail: s.sotiris@yahoo.gr [Department of Urology, Medical School, University of Ioannina, 45110 Ioannina (Greece); Astrakas, Loukas G., E-mail: astrakas@uoi.gr [Department of Medical Physics, Medical School, University of Ioannina, 45110 Ioannina (Greece); Sofikitis, Nikolaos, E-mail: akrosnin@hotmail.com [Department of Urology, Medical School, University of Ioannina, 45110 Ioannina (Greece); Argyropoulou, Maria I., E-mail: margyrop@cc.uoi.gr [Department of Radiology, Medical School, University of Ioannina, 45110 Ioannina (Greece)

    2015-07-15

    Highlights: • Functional MRI in the characterization of testicular germ cell tumors was assessed. • ADC values proved useful in the characterization of testicular germ cell tumors. • Testicular germ cell tumors had similar enhancement patterns of dynamic MRI. - Abstract: Introduction: The aim of this study is to investigate the role of apparent diffusion coefficient (ADC) values and dynamic contrast enhancement (DCE) patterns in differentiating seminomas from nonseminomatous germ cell tumors (NSGCTs). Materials and methods: The MRI examinations of the scrotum of 26 men with histologically proven testicular GCTs were reviewed. DWI was performed in all patients, using a single shot, multi-slice spin-echo planar diffusion pulse sequence and b-values of 0 and 900 s/mm{sup 2}. Subtraction DCE-MRI was performed in 20 cases using a 3D fast-field echo sequence after gadolinium administration. Time-signal intensity curves were created and semi-quantitative parameters (peak enhancement, time to peak, wash-in and wash-out rate) were calculated. The Student's t-test was used to compare the mean values of ADC, peak enhancement, time to peak, wash-in and wash-out rate between seminomas and NSGCTs. ROC analysis was also performed. Results: Histopathology disclosed the presence of 15 seminomas and 11 NSGCTs. The mean ± s.d. of ADC values (× 10{sup −3} mm{sup 2}/s) of seminomas (0.59 ± 0.009) were significantly lower than those of NSGCTs (0.90 ± 0.33) (P = 0.01). The optimal ADC cut-off value was 0.68 × 10{sup −3} mm{sup 2}/s. No differences between the two groups were observed for peak enhancement (P = 0.18), time to peak (P = 0.63) wash-in rate (P = 0.32) and wash-out rate (P = 0.18). Conclusions: ADC values may be used to preoperatively differentiate seminomas from NSGCTs.

  8. Seasonal changes of apparent thermal diffusivity of different kinds of soils

    Science.gov (United States)

    Dedecek, Petr; Safanda, Jan; Correia, Antonio; Rajver, Dusan; Cermak, Vladimir; Kresl, Milan

    2013-04-01

    The paper addresses the problem of seasonal changes of apparent thermal diffusivity (ATD) in different types of soils in different climatic conditions. The long-term (several years) temperature series recorded at observatories in Czechia, Slovenia and Portugal were processed using a program based on the error function solution of the heat conduction equation for a semi-infinite solid. The program simulates penetration of temperature changes represented by the observed time-temperature series in differently wide time floating intervals, and in different depth levels of the soil profile. Synthetic temperature series for different values of thermal diffusivity (with a step of 1E-8 m2/s) are automatically compared with measured temperature time series in a given depth. The ATD value minimizing the standard deviation of difference between the measured and computed temperature series is considered as the best approximation of reality. The method has been applied to the temperature series from (i) observatory in Prague, where the temperature monitoring in different kinds of soil (sand, bare clayey soil, grassy soil) and asphalt is running from 2002, (ii) Evora - Portugal (gravelly sand, running from 2005), and finally (iii) Malence - Slovenia (grassy clayey soil, running from 2003). The soil temperature is measured at the depths of 2, 5, 10, 20 and 50 cm at each of the observatories. Results have shown a gradual increase of the ATD with depth caused by the soil density gradient in case of Malence and Prague (excluding asphalt). The ATD of the upper part of sand (2 - 5 cm), contrary to grassy surface, is quite sensitive to weather pattern (e.g. periods of rain or drought), when the strong convective heat transport in soil can occur. The ATD values in Evora show an annual run connected with a long dry summer season. The seasonal pattern is characterized, especially in the upper part of soil, by a rapid decrease from 7*E-7 to 4*E-7 m2/s in June and a return to higher values

  9. Establishment of reference interval for liver specific biochemical parameters in apparently healthy north Indian population.

    Science.gov (United States)

    Yadav, Dharamveer; Mishra, Sandhya; Gupta, Monika; John, P J; Sharma, Praveen

    2013-01-01

    Reference intervals (RI) are the most common decision support tool used for interpretation of numerical laboratory reports. The quality of the RI can play as large a role in result interpretation as the quality of the result itself. As such there is hardly any study examining RI for liver specific biochemical parameters in Indian population especially north Indians having drastically different food habits as compared to rest of the India. So there is a need to establish the RI for north Indian population. Present study was conducted on 2,021 apparently healthy individuals of north Indian origin ranging in age from 15-60 years, were selected randomly using defined criteria. Lipemic, hemolysed, icteric and stored samples were also excluded adopting preanalytical criteria for rejection of sample. Non parametric methodology for determination of RI was adopted as most of the biochemical parameters included revealed non Gaussian distribution. Data were analyzed for middle 95 percentile (2.5th-97.5th percentile), median and 95 % confidence interval using SPSS software package version 10.0. The upper and the lower limit of RI (reported Vs observed) for bilirubin (0-1.2 Vs 0.30-1.30 mg/dL), serum glutamate oxaloacetate transferase (SGOT) (0-41 Vs 13-52.80 IU/L), serum glutamate pyruvate transferase (SGPT) (0-50 Vs 10-68 IU/L) showed wide variation as compared to reported standard RI however Gamma glutamyl transferase (GGT) (0-50 Vs 5.00-50.60 IU/L) remained within the reported standard RI. Further gender wise evaluation revealed higher cutoff in males (AST 14-55, ALT 11-70.35, GGT 6.76-51.09 in IU/L, bilirubin (0.40-1.34 mg/dL) as compared to females (SGOT 13-50.43, SGPT 9-63.43, GGT 3.92-48.70 in IU/L, Bilirubin 0.30-1.20 mg/dL) for both enzymatic and non enzymatic biochemical parameters. The variations may be attributed to dietary pattern smoking and alcoholism.

  10. Apparent metabolizable energy of crude glycerin originating from different sources in broiler chickens.

    Science.gov (United States)

    Dozier, W A; Kerr, B J; Branton, S L

    2011-11-01

    An energy balance experiment was conducted to determine the AME(n) of various crude glycerin samples, and to generate an equation to predict AME(n) of crude glycerin based on its chemical composition. Dietary treatments consisted of a corn-soybean meal basal diet with no added glycerin and a basal diet supplemented with 6% glycerin. Crude glycerin samples were obtained from biodiesel production facilities throughout the United States, which use a variety of lipid products as their initial feedstock. Two identical energy balance trials were conducted. In each trial, 864 male broilers (Ross × Ross 708) were fed a common starter diet until 17 d of age when they were switched to 1 of 12 experimental diets (6 replicates per treatment) from 17 to 22 d of age, with a 48-h collection period on d 21 and 22. Nitrogen-corrected apparent metabolizable energy values of crude glycerin samples were estimated by difference, whereby AME(n) of the basal diet was subtracted from the complete diet containing the test ingredient. The AME(n) of the basal diet and US Pharmacopeia-grade glycerin were determined to be 3,085 and 3,662 kcal/kg, respectively, whereas the AME(n) of the 10 crude glycerin samples ranged from 3,254 to 4,134 kcal/kg. Two crude glycerin samples had high levels of fatty acids compared with the other samples (24 and 35% vs. glycerin samples (3,806 vs. 3,611 kcal/kg, P glycerin samples, the stepwise regression equation to predict AME(n) was determined to be: [AME(n) (kcal/kg) = 1,605 - (19.13 × % methanol) + (39.06 × % fatty acid) + (23.47 × % glycerin)]; (R(2) = 0.25; SE = 379; P ≤ 0.01). These data indicate that glycerin is a good source of energy for broilers, and the AME(n) of glycerin is dependent on fatty acid, methanol, and water contents.

  11. Complexation of arsenite with dissolved organic matter: conditional distribution coefficients and apparent stability constants.

    Science.gov (United States)

    Liu, Guangliang; Cai, Yong

    2010-11-01

    The complexation of arsenic (As) with dissolved organic matter (DOM), although playing an important role in regulating As mobility and transformation, is poorly characterized, as evidenced by scarce reporting of fundamental parameters of As-DOM complexes. The complexation of arsenite (AsIII) with Aldrich humic acid (HA) at different pHs was characterized using a recently developed analytical technique to measure both free and DOM-bound As. Conditional distribution coefficient (KD), describing capacity of DOM in binding AsIII from the mass perspective, and apparent stability constant (Ks), describing stability of resulting AsIII-DOM complexes, were calculated to characterize AsIII-DOM complexation. LogKD of AsIII ranged from 3.7 to 2.2 (decreasing with increase of As/DOM ratio) at pH 5.2, from 3.6 to 2.6 at pH 7, and from 4.3 to 3.2 at pH=9.3, respectively. Two-site ligand binding models can capture the heterogeneity of binding sites and be used to calculate Ks by classifying the binding sites into strong (S1) and weak (S2) groups. LogKs for S1 sites are 7.0, 6.5, and 5.9 for pH 5.2, 7, and 9.3, respectively, which are approximately 1-2 orders of magnitude higher than for weak S2 sites. The results suggest that AsIII complexation with DOM increases with pH, as evidenced by significant spikes in concentrations of DOM-bound AsIII and in KD values at pH 9.3. In contrary to KD, logKs decreased with pH, in particular for S1 sites, probably due to the presence of negatively charged H2AsO3- and the involvement of metal-bridged AsIII-DOM complexation at pH 9.3.

  12. Apparent Stress Variation in Response to Seamount Subduction at Nicoya Peninsula, Costa Rica

    Science.gov (United States)

    Stankova-Pursley, J.; Bilek, S. L.; Phillips, W. S.; Newman, A. V.

    2008-12-01

    Seamounts are high relief features seen on many oceanic plates, including the Cocos plate offshore Costa Rica. As these features enter the subduction zone at Middle America Trench, they may perturb interface coupling by changing physical properties of the plate interface. Here we explore the role of seamounts on rupture process of microseismicity along Nicoya Peninsula, Costa Rica. This peninsula lies close to a region where down-going Cocos plate structure varies along-strike of the trench. The Cocos plate has low relief along the north and central parts of Nicoya Peninsula, where the subducting plate was created at East Pacific Rise (EPR). Seamounts dot the plate subducting at the southern tip of the peninsula, where the plate was created at Cocos-Nazca Spreading center (CNS). Given these structural differences, we are able to evaluate possible along-strike variations in earthquake source properties. We use 357 earthquakes from the Costa Rica Seismogenic Zone (CR-SEIZE) project to estimate the effects of seamount subduction on apparent stress (σa). We compute σa, which is a measure of stress drop combined with seismic efficiency, using waveform coda because of its proven stability relative to measurements using direct arrivals. We allow variable source scaling, finding that non-constant scaling provides good fit for our data, suggesting that seismic moment is not proportional to the cube root of corner frequency at ML 0.8 to 4.2. σa values for well constrained data indicate along strike variations between the northern and southern tips of the peninsula. Except in the region of a previously subducted seamount in the Gulf of Nicoya where the mean σa is 1.03 MPa, the southern and central portions of the peninsula have mean σa values 0.79 and 0.89 MPa respectively, while the mean σa value in the northern region is 1.66 MPa. The larger mean σa values in the northern region and in the Gulf of Nicoya implies that the interface is more strongly coupled where there

  13. Investigating bioremediation of petroleum hydrocarbons through landfarming using apparent electrical conductivity measurements

    Science.gov (United States)

    Van De Vijver, Ellen; Van Meirvenne, Marc; Seuntjens, Piet

    2015-04-01

    Bioremediation of soil contaminated with petroleum hydrocarbons through landfarming has been widely applied commercially at large scale. Biodegradation is one of the dominant pollutant removal mechanisms involved in landfarming, but strongly depends on the environmental conditions (e.g. presence of oxygen, moisture content). Conventionally the biodegradation process is monitored by the installation of field monitoring equipment and repeated sample collection and analysis. Because the presence of petroleum hydrocarbons and their degradation products can affect the electrical properties of the soil, proximal soil sensors such as electromagnetic induction (EMI) sensors may provide an alternative to investigate the biodegradation process of these contaminants. We investigated the relation between the EMI-based apparent electrical conductivity (ECa) of a landfarm soil and the presence and degradation status of petroleum hydrocarbons. The 3 ha study area was located in an oil refinery complex contaminated with petroleum hydrocarbons, mainly composed of diesel. At the site, a landfarm was constructed in 1999. The most recent survey of the petroleum hydrocarbon concentrations was conducted between 2011 and 2013. The sampling locations were defined by a grid with a 10 m by 10 m cell size and on each location a sample was taken from four successive soil layers with a thickness of 0.5 m each. Because the survey was carried out in phases using different georeferencing methods, the final dataset suffered from uncertainty in the coordinates of the sampling locations. In September 2013 the landfarm was surveyed for ECa with a multi-receiver electromagnetic induction sensor (DUALEM-21S) using motorized conveyance. The horizontal measurement resolution was 1 m by 0.25 m. On each measurement location the sensor recorded four ECa values representative of measurement depths of 0.5 m, 1.0 m, 1.6 m and 3.2 m. After the basic processing, the ECa measurements were filtered to remove

  14. Quantitative Apparent Diffusion Coefficients in the Characterization of Brain Tumors and Associated Peritumoral Edema

    Energy Technology Data Exchange (ETDEWEB)

    Server, A.; Schellhorn, T.; Nakstad, P.H. (Dept. of Neuroradiology, Div. of Radiology, Ullevaal Univ. Hospital, Univ. of Oslo, Oslo (Norway)); Kulle, B. (Epi-Gen Faculty Div. Akershus Univ. Hospital and Dept. of Biostatistics, Univ. of Oslo, Oslo (Norway)); Maehlen, J.; Kumar, T. (Dept. of Pathology, Ullevaal Univ. Hospital, Univ. of Oslo, Oslo (Norway)); Josefsen, R. (Dept. of Neurosurgery, Ullevaal Univ. Hospital, Univ. of Oslo, Oslo (Norway)); Langberg, C.W. (Cancer Centre, Ullevaal Univ. Hospital, Univ. of Oslo, Oslo (Norway))

    2009-07-15

    Background: Conventional magnetic resonance (MR) imaging has a number of limitations in the diagnosis of the most common intracranial brain tumors, including tumor specification and the detection of tumoral infiltration in regions of peritumoral edema. Purpose: To prospectively assess if diffusion-weighted MR imaging (DWI) could be used to differentiate between different types of brain tumors and to distinguish between peritumoral infiltration in high-grade gliomas, lymphomas, and pure vasogenic edema in metastases and meningiomas. Material and Methods: MR imaging and DWI was performed on 93 patients with newly diagnosed brain tumors: 59 patients had histologically verified high-grade gliomas (37 glioblastomas multiforme, 22 anaplastic astrocytomas), 23 patients had metastatic brain tumors, five patients had primary cerebral lymphomas, and six patients had meningiomas. Apparent diffusion coefficient (ADC) values of tumor (enhancing regions or the solid portion of tumor) and peritumoral edema, and ADC ratios (ADC of tumor or peritumoral edema to ADC of contralateral white matter, ADC of tumor to ADC of peritumoral edema) were compared with the histologic diagnosis. ADC values and ratios of high-grade gliomas, primary cerebral lymphomas, metastases, and meningiomas were compared by using ANOVA and multiple comparisons. Optimal thresholds of ADC values and ADC ratios for distinguishing high-grade gliomas from metastases were determined by receiver operating characteristic (ROC) curve analysis. Results: Statistically significant differences were found for minimum and mean of ADC tumor and ADC tumor ratio values between metastases and high-grade gliomas when including only one factor at a time. Including a combination of in total four parameters (mean ADC tumor, and minimum, maximum and mean ADC tumor ratio) resulted in sensitivity, specificity, positive (PPV), and negative predictive values (NPV) of 72.9, 82.6, 91.5, and 54.3% respectively. In the ROC curve analysis

  15. Evaluation of collection method and diet effects on apparent digestibility and energy values of swine diets.

    Science.gov (United States)

    Li, Y S; Tran, H; Bundy, J W; Burkey, T E; Kerr, B J; Nielsen, M K; Miller, P S

    2016-06-01

    Two experiments were conducted to investigate the effects of collection method and diet type on digestibility coefficients. In Exp. 1, 24 barrows were fed either a corn-soybean meal (CSBM) diet or CSBM with 20% dried distillers' grains with solubles (CSBM-DDGS). In Exp. 2, the effects of basal diet and collection method on determination of dried distillers' grains with solubles (DDGS) digestibility were studied using 24 barrows. The 4 diets used in Exp. 2 were: a CSBM (basal 1) , a barley-canola meal (BCM; basal 2), 80% basal 1 with 20% DDGS (CSBM-DDGS), and 80% basal 2 with 20% DDGS (BCM-DDGS). In both experiments, feces were collected using a time-based collection method (DY) or a "marker-to-marker" collection method (MM). Diets contained 0.5% of titanium dioxide (TiO) for estimating digestibility using the index marker approach (IM). The apparent total tract digestibility (ATTD) of DM and GE were lower ( diet than in the CSBM diet in Exp. 1 but were not different in Exp. 2. All the estimates of BCM-based diets were consistently lower ( diets. In Exp. 1, digestibility coefficients determined by the DY and MM were not different from each other, whereas those estimates were lower ( diet type and method for dietary digestibility coefficients. Digestibility and energy values estimated by the DY and MM were not different in pigs fed CSBM-based diets and the BCM-DDGS diet, whereas those estimates were greater ( diet and method for estimating DDGS digestibility. The ATTD of DM and GE of DDGS using the MM were greater ( diets. The mean DE and ME (as-fed basis) of DDGS were 3,994 and 3,688 kcal/kg, respectively, when estimated using the basal 1 diet and were 3,919 and 3,547 kcal/kg, respectively, when estimated using the basal 2 diet. In conclusion, both collection methods can be used to estimate energy and nutrient digestibility of diets and DDGS when using CSBM-based diets.

  16. Apparent and quantitative loss of fatty acids and triacylglycerols at frying temperatures

    Directory of Open Access Journals (Sweden)

    Berdeaux, O.

    2012-09-01

    Full Text Available Olive and sunflower oils were heated at 180 °C for 5, 10 and 15 hours with the aim of defining the changes in the contents of fatty acid methyl esters (FAME and triacylglycerols (TAG under frying conditions. Differences between apparent and real loss of FAME or TAG are defined for an adequate interpretation of the changes taking place at high temperature. Such differences depend on the expression of the results and frequently result in erroneous conclusions. Results showed that from the normalized composition it could be deduced that only the most unsaturated FAME (C18:2 or TAG containing it was significantly altered. However, quantitative data indicated that all the unsaturated FAME were degraded in samples of olive oil and sunflower oil whose levels of alteration ranged from 14.6 to 35.4% polar compounds. With regard to TAG, their loss depended on both the number of double bonds and the concentration of the linoleyl group, which is the most unsaturated fatty acyl group in both oils.

    Aceites de oliva y girasol se calentaron a 180 °C durante 5, 10 y 15 horas con el objetivo de definir los cambios en la concentración de ácidos grasos y especies de triglicéridos en condiciones de fritura. Se definen las diferencias entre la pérdida aparente y cuantitativa de ácidos grasos y triglicéridos que dependen de la forma de expresión de los resultados dando lugar en muchas ocasiones a interpretaciones erróneas. Así, a partir de la composición normalizada, podría deducirse que sólo el ácido graso más insaturado en los aceites (C18:2 se altera. Sin embargo, los datos cuantitativos muestran claramente que en muestras con niveles de compuestos polares entre 14.6 y 35.4%, todos los ácidos grasos insaturados sufren degradación significativa en ambos aceites. Con respecto a los cambios en los distintos triglicéridos, su pérdida cuantitativa dependió no sólo de su número de dobles enlaces sino también del contenido del ácido m

  17. Fossil gaps inferred from phylogenies alter the apparent nature of diversification in dragonflies and their relatives

    Directory of Open Access Journals (Sweden)

    Nicholson David B

    2011-09-01

    Full Text Available Abstract Background The fossil record has suggested that clade growth may differ in marine and terrestrial taxa, supporting equilibrial models in the former and expansionist models in the latter. However, incomplete sampling may bias findings based on fossil data alone. To attempt to correct for such bias, we assemble phylogenetic supertrees on one of the oldest clades of insects, the Odonatoidea (dragonflies, damselflies and their extinct relatives, using MRP and MRC. We use the trees to determine when, and in what clades, changes in taxonomic richness have occurred. We then test whether equilibrial or expansionist models are supported by fossil data alone, and whether findings differ when phylogenetic information is used to infer gaps in the fossil record. Results There is broad agreement in family-level relationships between both supertrees, though with some uncertainty along the backbone of the tree regarding dragonflies (Anisoptera. "Anisozygoptera" are shown to be paraphyletic when fossil information is taken into account. In both trees, decreases in net diversification are associated with species-poor extant families (Neopetaliidae, Hemiphlebiidae, and an upshift is associated with Calopterygidae + Polythoridae. When ghost ranges are inferred from the fossil record, many families are shown to have much earlier origination dates. In a phylogenetic context, the number of family-level lineages is shown to be up to twice as high as the fossil record alone suggests through the Cretaceous and Cenozoic, and a logistic increase in richness is detected in contrast to an exponential increase indicated by fossils alone. Conclusions Our analysis supports the notion that taxa, which appear to have diversified exponentially using fossil data, may in fact have diversified more logistically. This in turn suggests that one of the major apparent differences between the marine and terrestrial fossil record may simply be an artifact of incomplete sampling

  18. Remote sensing of the mountain cryosphere using texture filters and apparent thermal inertia

    Science.gov (United States)

    Brenning, A.; Fieguth, P.; Long, S.; Peña, M. A.; Soliman, A. S.

    2011-12-01

    Rock glaciers and debris-covered glaciers on Earth, and analog landforms on Mars, constitute hidden water resources and components of the cryosphere that are difficult to map or characterize using remote sensors. We utilize two innovative approaches in this field, (1) texture filters and (2) thermal features, in particular apparent thermal inertia (ATI), in order to investigate ice-debris landforms and in particular rock glaciers in the semi-arid Andes. Even though the ridge-and-furrow surface patterns are probably the most characteristic morphological features of rock glaciers, our study is the first to apply texture filters to the problem of remotely-sensed rock glacier detection. Gabor filters are designed to detect zebra-like patterns and are therefore an obvious choice for this study. Texture features derived from a Gabor filterbank were calculated from panchromatic IKONOS orthoimagery and used to discriminate rock glacier and other debris surfaces utilizing four classification methods of varying complexity: generalized linear model (GLM), generalized additive model (GAM), support vector machine (SVM), and tree ensembles (Bundling). Bundling outperformed the other methods in most situations studied, achieving an area under the ROC curve (AUROC) of 0.72-0.80 in different spatial cross-validation scenarios. This study focused on a narrow area of interest that cannot be easily identified as non-rock glacier area based on topographic criteria, and therefore significantly better results are expected in practical mapping situations in combination with terrain attributes as predictors. Thermal remote sensing has been of limited use in mountain cryospheric studies. In addition to land surface temperature (LST), ATI is of particular interest in this context. Thermal inertia is a single thermophysical material property that determines the amplitude of temperature variations at the surface of a periodically heated half-space, and shows promise in discriminating different

  19. Apparent metabolizable energy value of meat and bone meal for white pekin ducks.

    Science.gov (United States)

    Adedokun, S A; Adeola, O

    2005-10-01

    Apparent metabolizable energy and AMEn values of 12 samples of meat and bone meal (MBM) were determined using 288 ducks with an average weight of 3.4 kg. Diets were formulated for each of the 12 MBM samples by substituting 0, 5, or 10% MBM in a basal corn-soybean meal diet; corn and soybean meal were adjusted at the same ratio to account for the substitution. Each diet was fed to 8 ducks in individual cages in a metabolism assay that employed a 4-d acclimation period followed by 3 d of excreta collection. The gross energy (GE), CP, crude fat (CF), ash, Ca, and P contents of the MBM samples, on a per kilogram of DM basis, ranged from 3,493 to 4,732 kcal, 496.7 to 619.1 g, 91.1 to 151.2 g, 200.3 to 381.9 g, 54.3 to 145.8 g, and 25.6 to 61.7 g, respectively. The AME and AMEn values of the MBM samples were calculated from the slope of the regression of MBM contribution (in kcal) to AME and AMEn intake, respectively, against the amount (in kg) of MBM in diet. The AME or AMEn of the 12 MBM samples ranged from 1,781 to 3,916 kcal/kg of DM or 1,772 to 3,662 kcal/kg of DM, respectively. The variation in AME was described by the regression equation AME = -7,272 + 5.000 GE (kcal/kg) - 19.43 CP (g/kg) - 29.51 CF (g/kg) - 297.17 P (g/kg) + 106.09 Ca (g/kg) + 17.03 ash (g/kg), with R2 = 0.552 and SD = 753. The corresponding equation for AMEn was = -7,389 + 4.584 GE (kcal/kg) - 16.74 CP (g/kg) - 25.11 CF (g/kg) - 218.24 P (g/kg) + 97.29 Ca (g/kg) + 7.95 ash (g/kg), with R2 = 0.598 and SD = 586. The results reveal that variation in each of the chemical components of MBM alone is not the sole determinant of AME or AMEn value of MBM, but that the interactions among these components influence energy utilization in MBM for ducks.

  20. Respiratory symptoms and airway responsiveness in apparently healthy workers exposed to flour dust.

    Science.gov (United States)

    Bohadana, A B; Massin, N; Wild, P; Kolopp, M N; Toamain, J P

    1994-06-01

    Our aim was to measure the levels of exposure to wheat flour dust in a modern industrial bakery, and to assess the relationship between respiratory symptoms, sensitization to wheat flour antigens and airway responsiveness in the workforce. Forty four flour-exposed male workers and 164 unexposed controls were examined. Inspirable dust concentrations were measured using personal samplers. Respiratory symptoms were assessed by questionnaire, sensitization to wheat flour antigens by skin-prick tests, and methacholine airway challenge (MAC) test using an abbreviated method. Subjects were labelled MAC+ if forced expiratory volume in one second (FEV1) fell by 20% or more. The linear dose-response slope (DRS) was calculated as the percentage fall in FEV1 at last dose divided by the total dose administered. Inspirable dust concentrations were within acceptable limits in all working areas but one. The proportion of subjects with one or more symptoms and with airway hyperresponsiveness was significantly greater among flour-exposed workers than among controls. Using logistic or linear regression analysis, airway responsiveness was found to be strongly related to working at the bakery and to the baseline level of lung function. A positive skin-prick test was found in only 11% of flour-exposed workers and 6% of controls. In conclusion, our data show that despite exposure to relatively low concentration levels of inspirable flour dust, subjects working in the baking industry are at risk of developing both respiratory symptoms and airway hyperresponsiveness.

  1. Hematological and serum biochemical profile of apparently healthy hariana cattle heifers in northern India.

    Science.gov (United States)

    Mahima; Singh, Krishna Veer; Verma, Amit Kumar; Kumar, Vinod; Singh, Shanker Kumar; Roy, Debashis

    2013-11-01

    The 'Hariana' breed of cattle has been proved to be highly adaptable to harsh climatic conditions and resistant to common diseases prevalent in India. In this study, the normal reference values of hematological and serum proteins and other blood biochemical parameters were determined in the heifers of Hariana breed maintained at Instructional livestock farm complex, DUVASU, Mathura, India. A total of twenty four animals were used in this study. Blood was taken aseptically from all the animals and transported to laboratory for hematological and biochemical analysis. The hematological parameters (Hemoglobin, total erythrocyte count, total leukocyte count, packed cell volume) and biochemical parameters (Total protein, total albumin, albumin globulin ratio, urea, creatinine, calcium, phosphorous, calcium phosphorous ratio, AST, ALT) values were statistically analyzed, mean and standard deviations were calculated and set as reference values. This study reported hematological and serum biochemical values which could serve as baseline information for comparison in conditions of nutrient deficiency, physiological and health status of Hariana cattle heifers in India.

  2. Finding related functional neuroimaging volumes

    DEFF Research Database (Denmark)

    Nielsen, Finn Årup; Hansen, Lars Kai

    2004-01-01

    We describe a content-based image retrieval technique for finding related functional neuroimaging experiments by voxelization of sets of stereotactic coordinates in Talairach space, comparing the volumes and reporting related volumes in a sorted list. Voxelization is accomplished by convolving each...... coordinate with a Gaussian kernel. The scheme allows us to compare experiments represented as either lists of coordinates or volumes, and we introduce alternative entrances to databases by image-based indices constructed via novelty measures and singular value decomposition....

  3. A Review of the Application of Computer Vision to the Inspection and Assessment of Textiles Apparent Properties

    Institute of Scientific and Technical Information of China (English)

    步红刚; 李立轻; 黄秀宝

    2004-01-01

    Due to its advantages of objectiveness, automation, accuracy and fastness in various applications, the technology of computer vision has become one of the studying hotspots in the area of the objective inspection and assessment of textiles apparent properties during the past two decades in the world. Both a brief review of its applications in the recent decade both at home and abroad to the automatic inspection and assessment of the various apparent properties of the textiles, such as yarn, woven fabrics and knitting fabrics, carpet fabrics, nonwoven fabrics and textile webs, etc., and a detailed introduction to the research work including the objective evaluation of fabric wrinkle grade, automatic fabric defects detection and assessment of fabric pilling grade, etc., that was conducted by our research section, i.e., Computer Vision's Textiles Application Research Section, College of Textiles, Dong Hua University, have been provided. Experimental results have proved the feasibilities of the approaches used by us in the applications to the objective inspection and assessment of fabric apparent properties, and also indicated that the technology of computer vision is a power tool for the objective and automatic inspection and assessment of textiles apparent properties, and that it has a bright application future.

  4. Frequent germ-line succinate dehydrogenase subunit D gene mutations in patients with apparently sporadic parasympathetic paraganglioma

    NARCIS (Netherlands)

    H. Dannenberg (Hilde); W.N.M. Dinjens (Winand); M. Abbou; H. van Urk (Hero); B.K. Pauw; D. Mouwen; W.J. Mooi (Wolter); R.R. de Krijger (Ronald)

    2002-01-01

    textabstractPURPOSE: Recently, familial paraganglioma (PGL) was shown to be caused bymutations in the gene encoding succinate dehydrogenase subunit D (SDHD). However, the prevalence of SDHD mutations in apparently sporadic PGL is unknown. We studied the frequency and spectrum of ge

  5. A comparative study of the apparent total tract digestibility of fibre in Icelandic and Danish Warmblood horses

    DEFF Research Database (Denmark)

    Jensen, Rasmus Bovbjerg; Brøkner, Christine; Knudsen, Knud Erik Bach;

    2010-01-01

    Four Icelandic (ICE) and four Danish Warmblood (DW) horses were used in a crossover study with two treatments to investigate the effect of breed and the effect of stage of maturity of haylage on the apparent total tract digestibility (ATTD) of a diet consisting of sugar beet pulp, black oats...

  6. Complete genome sequence of a genotype XVII Newcastle disease virus, isolated from an apparently healthy domestic duck in Nigeria

    Science.gov (United States)

    The first complete genome sequence of a strain of Newcastle disease virus (NDV) of genotype XVII is described here. A velogenic strain (duck/Nigeria/903/KUDU-113/1992) was isolated from an apparently healthy free-roaming domestic duck sampled in Kuru, Nigeria, in 1992. Phylogenetic analysis of the f...

  7. OBSERVATION OF MOVEMENTS DURING SLEEP IN ALTE (APPARENT LIFE-THREATENING EVENT) AND APNEIC INFANTS - A PILOT-STUDY

    NARCIS (Netherlands)

    EINSPIELER, C; PRECHTL, HFR; VANEYKERN, L; DEROOS, B

    1994-01-01

    Fourteen infants of 2 months or 6 months of age were video-recorded during polysomnography. Four were normal infants, five had a history of ALTE (apparent life threatening event) and five had repeated and prolonged apnoea during sleep. Two ALTE infants have been recorded at 2 months as well as at 6

  8. Apparent diffusion coefficient evaluation for secondary changes in the cerebellum of rats after middle cerebral artery occlusion

    Institute of Scientific and Technical Information of China (English)

    Yunjun Yang; Lingyun Gao; Jun Fu; Jun Zhang; Yuxin Li; Bo Yin; Weijian Chen; Daoying Geng

    2013-01-01

    Supratentorial cerebral infarction can cause functional inhibition of remote regions such as the ce-rebel um, which may be relevant to diaschisis. This phenomenon is often analyzed using positron emission tomography and single photon emission CT. However, these methods are expensive and radioactive. Thus, the present study quantified the changes of infarction core and remote regions after unilateral middle cerebral artery occlusion using apparent diffusion coefficient values. Diffu-sion-weighted imaging showed that the area of infarction core gradual y increased to involve the cerebral cortex with increasing infarction time. Diffusion weighted imaging signals were initial y in-creased and then stabilized by 24 hours. With increasing infarction time, the apparent diffusion coefficient value in the infarction core and remote bilateral cerebel um both gradual y decreased, and then slightly increased 3-24 hours after infarction. Apparent diffusion coefficient values at mote regions (cerebel um) varied along with the change of supratentorial infarction core, suggesting that the phenomenon of diaschisis existed at the remote regions. Thus, apparent diffusion coeffi-cient values and diffusion weighted imaging can be used to detect early diaschisis.

  9. Vitamin A equivalency and apparent absorption of ß-carotene in ileostomy subjects using a dual-isotope dilution technique

    NARCIS (Netherlands)

    Bouwman, C.A.; Naber, T.H.J.; Breemen, van R.B.; Zhu, D.; Dicke, H.; Siebelink, E.; Hulshof, P.J.M.; Russel, F.G.M.; Schaafsma, G.; West, C.E.

    2010-01-01

    The objective was to quantify the vitamin A equivalency of ß-carotene in two diets using a dual-isotope dilution technique and the apparent ß-carotene absorption as measured by the oral–faecal balance technique. Seventeen healthy adults with an ileostomy completed the 4-week diet-controlled, cross-o

  10. Vitamin A equivalency and apparent absorption of beta-carotene in ileostomy subjects using a dual-isotope dilution technique.

    NARCIS (Netherlands)

    Loo-Bouwman, C.A. Van; Naber, T.H.; Breemen, R.B. van; Zhu, D.; Dicke, H.; Siebelink, E.; Hulshof, P.J.; Russel, F.G.M.; Schaafsma, G.; West, C.E.

    2010-01-01

    The objective was to quantify the vitamin A equivalency of beta-carotene in two diets using a dual-isotope dilution technique and the apparent beta-carotene absorption as measured by the oral-faecal balance technique. Seventeen healthy adults with an ileostomy completed the 4-week diet-controlled, c

  11. Glycerin and essential oils in the diet of Nellore bulls finished in feedlot: animal performance and apparent digestibility

    Directory of Open Access Journals (Sweden)

    Lorrayny Galoro da Silva

    2014-05-01

    Full Text Available Current research studied the effect of partial replacing corn by glycerin and essential oils addition in the diet of Nellore bulls finished in feedlot on feed intake, animal performance and three markers were assessed to estimate apparent digestibility. Thirty bulls with average weight 400 ± 34.1 kg and 22 ± 2 months old were housed in collective pens (10 x 20 m2 for 63 days. The bulls were randomly assigned to 3 diets (10 bulls per treatment: CON – Control (without glycerin or Essential® oils; GLY – Glycerin (15% on dry matter - DM; and GEO – Glycerin (15% on DM and Essential® oils (3 g animal day-1. Three different markers were used to estimate apparent digestibility in the diets: indigestible dry matter –iDM; indigestible neutral detergent fiber – iNDF; and purified lignin – LIPE®. Feed efficiency and animal performance were not affected by the corn partial replacing by glycerin. No effects were found in partial corn replacing by glycerin and Essential® oils addition in the diets on the fecal output, crude protein and ether extract digestibility among the diets. The DM and OM apparent digestibility were higher for bulls fed with glycerin and Essential® oils. The CHO digestibility was higher for CON diet. The markers iDM, iNDF and LIPE® were similarly to estimate apparent digestibility to all nutrients in the diets.

  12. Studies on the mechanism by which a high intake of soybean oil depresses the apparent digestibility of fibre in horses

    NARCIS (Netherlands)

    Jansen, W.L.; Sloet van Oldruitenborgh-Oosterbaan, M.M.; Cone, J.W.; Vries, de H.T.; Hallebeek, J.M.; Hovenier, R.; Kuilen, van der J.; Huurdeman, C.M.; Verstappen, D.C.G.M.; Gresnigt, M.C.; Beynen, A.C.

    2007-01-01

    An increased intake of soybean oil at the expense of an iso-energetic amount of non-structural carbohydrates reduces the apparent digestibility of fibre in horses. Literature data indicate that bile acids and linoleic acid (C18:2 n ¿ 6) may inhibit growth of pure cultures of microorganisms. In the p

  13. An in vitro model of skeletal muscle volume regulation.

    Directory of Open Access Journals (Sweden)

    Anna Wibberley

    Full Text Available Hypertonic media causes cells to shrink due to water loss through aquaporin channels. After acute shrinkage, cells either regulate their volume or, alternatively, undergo a number of metabolic changes which ultimately lead to cell death. In many cell types, hypertonic shrinkage is followed by apoptosis. Due to the complex 3D morphology of skeletal muscle and the difficulty in obtaining isolated human tissue, we have begun skeletal muscle volume regulation studies using the human skeletal muscle cell line TE671RD. In this study we investigated whether hypertonic challenge of the human skeletal muscle cell line TE671RD triggered cell death or evoked a cell volume recovery response.The cellular volume of TE671RD cells was calculated from the 2D surface area. Cell death was assessed by both the trypan blue live/dead assay and the TUNEL assay.Medium osmolality was increased by addition of up to 200 mM sucrose. Addition of 200 mM sucrose resulted in mean cell shrinkage of 44±1% after 30 mins. At later time points (2 and 4 hrs two separate cell subpopulations with differing mean cell volume became apparent. The first subpopulation (15±2% of the total cell number continued to shrink whereas the second subpopulation had an increased cell volume. Cell death was observed in a small proportion of cells (approximately 6-8%.We have established that a substantial proportion of TE671RD cells respond to hypertonic challenge with RVI, but that these cells are resistant to hypertonicity triggered cell death.

  14. Apparent digestibility coefficients and consumption of corn silage with and without Bt gene in sheep

    Directory of Open Access Journals (Sweden)

    Camila Memari Trava

    2012-12-01

    Full Text Available Corn silage is the most important preserved food for ruminants. The transgenic corn was inserted into the genetic code Bt gene (Bacillus thuringiensis that expresses a toxic protein to caterpillars pests of maize, reducing production costs. To evaluate the varieties of plant corn silage DKB and AG with or without the Bt gene on the voluntary intake of DM (g/day and apparent digestibility coefficients (CDA of nutrients in sheep, the experiment was conducted at the Institute of Animal Science Nova Odessa-SP. Were used 20 sheep and the experimental design was randomized blocks in scheme factorial type 2x2 (two varieties of plant corn to silage, with the presence or absence of Bt gene, with five animals per treatment. These animals were housed in metabolism cages, with collector and separator feces and urine for 21 days, comprising 8 days for diet adaptation and 7 days for determination of intake, followed by 6 days of collection of feces, to measure DMI (g/day, CDA DM, CP and NDF. Samples of feed offered, leftovers and feces were identified and placed in a circulating air oven maintained at 55°C to constant weight. The analyses were performed in Bromatological Analysis Laboratory of the Institute of Animal Science. To CTMS (g/day was interaction effect (p<0.05 than in the variety AG (779.36 was greater than DKB (637.52, because the DM content of the sheet AG (31.09 was superior to DKB (29.17. The AG (779.36 was higher than your counterpart isogenic without the gene (575.15 p<0.05. The DKB without the gene (637.52 did not differ (p>0.05 from your counterpart DKBBt with the gene (590.78. The lowest total DM intake in g/day was observed for varieties with Bt gene insertion (genetically modified organism - GMO and a possible explanation is the higher value of NDF in the silages of variety with the Bt gene in relation to their isogenic counterparts without the gene. The CDA, DM and NDF no had interaction effect between varieties factors and GMO (p>0

  15. Cosmological Measures without Volume Weighting

    CERN Document Server

    Page, Don N

    2008-01-01

    Many cosmologists (myself included) have advocated volume weighting for the cosmological measure problem, weighting spatial hypersurfaces by their volume. However, this often leads to the Boltzmann brain problem, that almost all observations would be by momentary Boltzmann brains that arise very briefly as quantum fluctuations in the late universe when it has expanded to a huge size, so that our observations (too ordered for Boltzmann brains) would be highly atypical and unlikely. Here it is suggested that volume weighting may be a mistake. Volume averaging is advocated as an alternative. One consequence would be a loss of the argument for eternal inflation.

  16. Apparent mass of the human body in the vertical direction: Effect of a footrest and a steering wheel

    Science.gov (United States)

    Toward, M. G. R.; Griffin, M. J.

    2010-04-01

    The apparent mass of the seated human body influences the vibration transmitted through a car seat. The apparent mass of the body is known to be influenced by sitting posture but the influence of the position of the hands and the feet is not well understood. This study was designed to quantify the influence of steering wheel location and the position of a footrest on the vertical apparent mass of the human body. The influences of the forces applied by the hands to a steering wheel and by the feet to a footrest were also investigated. Twelve subjects were exposed to whole-body vertical random vibration (1.0 m s -2 rms over the frequency range 0.13-40.0 Hz) while supported by a rigid seat with a backrest reclined to 15°. The apparent mass of the body was measured with five horizontal positions and three vertical positions of a steering wheel and also with hands in the lap, and with five horizontal positions of a footrest. The influence of five forward forces (0, 50, 100, 150, 200 N) applied separately to the 'steering wheel' and the footrest were also investigated as well as a 'no backrest' condition. With their hands in their laps, subjects exhibited a resonance around 6.7 Hz, compared to 4.8 Hz when sitting upright with no backrest. In the same posture holding a steering wheel, the mass supported on the seat surface decreased and there was an additional resonance at 4 Hz. Moving the steering wheel away from the body reduced the apparent mass at the primary resonance frequency and increased the apparent mass around the 4 Hz resonance. As the feet moved forward, the mass supported on the seat surface decreased, indicating that the backrest and footrest supported a greater proportion of the subject weight. Applying force to either the steering wheel or the footrest reduced the apparent mass at resonance and decreased the mass supported on the seat surface. It is concluded that the positions and contact conditions of the hands and the feet affect the biodynamic

  17. An effective medium approach to predict the apparent contact angle of drops on super-hydrophobic randomly rough surfaces.

    Science.gov (United States)

    Bottiglione, F; Carbone, G

    2015-01-14

    The apparent contact angle of large 2D drops with randomly rough self-affine profiles is numerically investigated. The numerical approach is based upon the assumption of large separation of length scales, i.e. it is assumed that the roughness length scales are much smaller than the drop size, thus making it possible to treat the problem through a mean-field like approach relying on the large-separation of scales. The apparent contact angle at equilibrium is calculated in all wetting regimes from full wetting (Wenzel state) to partial wetting (Cassie state). It was found that for very large values of the roughness Wenzel parameter (r(W) > -1/ cos θ(Y), where θ(Y) is the Young's contact angle), the interface approaches the perfect non-wetting condition and the apparent contact angle is almost equal to 180°. The results are compared with the case of roughness on one single scale (sinusoidal surface) and it is found that, given the same value of the Wenzel roughness parameter rW, the apparent contact angle is much larger for the case of a randomly rough surface, proving that the multi-scale character of randomly rough surfaces is a key factor to enhance superhydrophobicity. Moreover, it is shown that for millimetre-sized drops, the actual drop pressure at static equilibrium weakly affects the wetting regime, which instead seems to be dominated by the roughness parameter. For this reason a methodology to estimate the apparent contact angle is proposed, which relies only upon the micro-scale properties of the rough surface.

  18. Heliophysics 3 Volume Set

    Science.gov (United States)

    Schrijver, Carolus J.; Siscoe, George L.

    2010-11-01

    Volume 1: Preface; 1. Prologue Carolus J. Schrijver and George L. Siscoe; 2. Introduction to heliophysics Thomas J. Bogdan; 3. Creation and destruction of magnetic field Matthias Rempel; 4. Magnetic field topology Dana W. Longcope; 5. Magnetic reconnection Terry G. Forbes; 6. Structures of the magnetic field Mark B. Moldwin, George L. Siscoe and Carolus J. Schrijver; 7. Turbulence in space plasmas Charles W. Smith; 8. The solar atmosphere Viggo H. Hansteen; 9. Stellar winds and magnetic fields Viggo H. Hansteen; 10. Fundamentals of planetary magnetospheres Vytenis M. Vasyliūnas; 11. Solar-wind magnetosphere coupling: an MHD perspective Frank R. Toffoletto and George L. Siscoe; 12. On the ionosphere and chromosphere Tim Fuller-Rowell and Carolus J. Schrijver; 13. Comparative planetary environments Frances Bagenal; Bibliography; Index. Volume 2: Preface; 1. Perspective on heliophysics George L. Siscoe and Carolus J. Schrijver; 2. Introduction to space storms and radiation Sten Odenwald; 3. In-situ detection of energetic particles George Gloeckler; 4. Radiative signatures of energetic particles Tim Bastian; 5. Observations of solar and stellar eruptions, flares, and jets Hugh Hudson; 6. Models of coronal mass ejections and flares Terry Forbes; 7. Shocks in heliophysics Merav Opher; 8. Particle acceleration in shocks Dietmar Krauss-Varban; 9. Energetic particle transport Joe Giacalone; 10. Energy conversion in planetary magnetospheres Vytenis Vasyliūnas; 11. Energization of trapped particles Janet Green; 12. Flares, CMEs, and atmospheric responses Tim Fuller-Rowell and Stanley C. Solomon; 13. Energetic particles and manned spaceflight 358 Stephen Guetersloh and Neal Zapp; 14. Energetic particles and technology Alan Tribble; Appendix I. Authors and editors; List of illustrations; List of tables; Bibliography; Index. Volume 3: Preface; 1. Interconnectedness in heliophysics Carolus J. Schrijver and George L. Siscoe; 2. Long-term evolution of magnetic activity of Sun

  19. Volume and Surface-Enhanced Volume Negative Ion Sources

    CERN Document Server

    Stockli, M P

    2013-01-01

    H- volume sources and, especially, caesiated H- volume sources are important ion sources for generating high-intensity proton beams, which then in turn generate large quantities of other particles. This chapter discusses the physics and technology of the volume production and the caesium-enhanced (surface) production of H- ions. Starting with Bacal's discovery of the H- volume production, the chapter briefly recounts the development of some H- sources, which capitalized on this process to significantly increase the production of H- beams. Another significant increase was achieved in the 1990s by adding caesiated surfaces to supplement the volume-produced ions with surface-produced ions, as illustrated with other H- sources. Finally, the focus turns to some of the experience gained when such a source was successfully ramped up in H- output and in duty factor to support the generation of 1 MW proton beams for the Spallation Neutron Source.

  20. Socioeconomic status and the cerebellar grey matter volume. Data from a well-characterised population sample.

    Science.gov (United States)

    Cavanagh, Jonathan; Krishnadas, Rajeev; Batty, G David; Burns, Harry; Deans, Kevin A; Ford, Ian; McConnachie, Alex; McGinty, Agnes; McLean, Jennifer S; Millar, Keith; Sattar, Naveed; Shiels, Paul G; Tannahill, Carol; Velupillai, Yoga N; Packard, Chris J; McLean, John

    2013-12-01

    The cerebellum is highly sensitive to adverse environmental factors throughout the life span. Socioeconomic deprivation has been associated with greater inflammatory and cardiometabolic risk, and poor neurocognitive function. Given the increasing awareness of the association between early-life adversities on cerebellar structure, we aimed to explore the relationship between early life (ESES) and current socioeconomic status (CSES) and cerebellar volume. T1-weighted MRI was used to create models of cerebellar grey matter volumes in 42 adult neurologically healthy males selected from the Psychological, Social and Biological Determinants of Ill Health study. The relationship between potential risk factors, including ESES, CSES and cerebellar grey matter volumes were examined using multiple regression techniques. We also examined if greater multisystem physiological risk index-derived from inflammatory and cardiometabolic risk markers-mediated the relationship between socioeconomic status (SES) and cerebellar grey matter volume. Both ESES and CSES explained the greatest variance in cerebellar grey matter volume, with age and alcohol use as a covariate in the model. Low CSES explained additional significant variance to low ESES on grey matter decrease. The multisystem physiological risk index mediated the relationship between both early life and current SES and grey matter volume in cerebellum. In a randomly selected sample of neurologically healthy males, poorer socioeconomic status was associated with a smaller cerebellar volume. Early and current socioeconomic status and the multisystem physiological risk index also apparently influence cerebellar volume. These findings provide data on the relationship between socioeconomic deprivation and a brain region highly sensitive to environmental factors.