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1

Bunch Length Measurements With Laser/SR Cross-Correlation  

SciTech Connect

By operating SPEAR3 in low-{alpha} mode the storage ring can generate synchrotron radiation pulses of order 1ps. Applications include pump-probe x-ray science and the production of THz radiation in the CSR regime. Measurements of the bunch length are difficult, however, because the light intensity is low and streak cameras typically provide resolution of only a few ps. Tests are now underway to resolve the short bunch length using cross-correlation between a 60-fs Ti:Sapphire laser and the visible SR beam in a BBO crystal. In this paper we report on the experimental setup, preliminary measurements and prospects for further improvement.

Miller, Timothy; /Stanford U., Phys. Dept.; Daranciang, Dan; /Stanford U., Phys. Dept.; Lindenberg, Aaron; /Stanford U., Phys. Dept.; Corbett, Jeff; /SLAC; Fisher, Alan; /SLAC; Goodfellow, John; /SLAC; Huang, Xiaobiao; /SLAC; Mok, Walter; /SLAC; Safranek, James; /SLAC; Wen, Haidan; /SLAC

2012-07-06

2

Measuring Length  

NSDL National Science Digital Library

This article focuses on young students encountering the measurement of length. The article cites examples of key concepts in recognizing length as an attribute and in proper and improper ways to measure length. Conservation and additivity of length, standard and non-standard units, iteration, and the zero point are among the topics presented.

2009-08-01

3

Measurement of the Correlation and Coherence Lengths in Boundary Layer Flight Data  

NASA Technical Reports Server (NTRS)

Wall pressure data acquired during flight tests at several flight conditions are analyzed and the correlation and coherence lengths of the data reported. It is shown how the frequency bandwidth of the analysis biases the correlation length and how the convection of the flow acts to reduce the coherence length. Coherence lengths measured in the streamwise direction appear much longer than would be expected based on classical results for flow over a flat plat.

Palumbo, Daniel L.

2011-01-01

4

Turbulence radial correlation length measurements using Doppler reflectometry in TJ-II  

NASA Astrophysics Data System (ADS)

First measurements carried out using radial correlation Doppler reflectometry in the TJ-II stellarator are presented. Broad scans in the probing beam angle are performed to study the behaviour of the radial correlation length measured by Doppler reflectometry. A comparison with the simulation results obtained using a two-dimensional full-wave code (Blanco and Estrada 2013 Plasma Phys. Control. Fusion 55 125006) indicates that both linear and non-linear regimes are found. In linear regimes, the procedure to calculate the best estimation for the turbulence radial correlation length found in the simulations is applied providing sensible results. These measurements, viewed as a validation of the simulation results, show that Doppler reflectometry provides a good estimation of the turbulence radial correlation length in linear regimes if the probing beam angle is scanned.

Fernández-Marina, F.; Estrada, T.; Blanco, E.

2014-07-01

5

Measuring the correlation length of intergalactic magnetic fields from observations of gamma-ray induced cascades  

NASA Astrophysics Data System (ADS)

Context. The imaging and timing properties of ?-ray emission from electromagnetic cascades initiated by very-high-energy (VHE) ?-rays in the intergalactic medium depend on the strength B and correlation length ?B of intergalactic magnetic fields (IGMF). Aims: We study the possibility of measuring both B and ?B via observations of the cascade emission with ?-ray telescopes. Methods: For each measurement method, we find two characteristics of the cascade signal, which are sensitive to the IGMF B and ?B values in different combinations. For the case of IGMF measurement using the observation of extended emission around extragalactic VHE ?-ray sources, the two characteristics are the slope of the surface brightness profile and the overall size of the cascade source. For the case of IGMF measurement from the time delayed emission, these two characteristics are the initial slope of the cascade emission light curve and the overall duration of the cascade signal. Results: We show that measurement of the slope of the cascade induced extended emission and/or light curve can both potentially provide measure of the IGMF correlation length, provided it lies within the range 10 kpc ? ?B ? 1 Mpc. For correlation lengths outside this range, gamma-ray observations can provide an upper or lower bound on ?B. The latter of the two methods holds great promise in the near future for providing a measurement/constraint using measurements from present/next-generation ?-ray-telescopes. Conclusions: Measurement of the IGMF correlation length will provide an important constraint on its origin. In particular, it will enable to distinguish between an IGMF of galactic wind origin from an IGMF of cosmological origin.

Neronov, A.; Taylor, A. M.; Tchernin, C.; Vovk, I.

2013-06-01

6

Measurement of surface plasmon correlation length differences using Fibonacci deterministic hole arrays.  

PubMed

Using terahertz (THz) transmission measurements through two-dimensional Fibonacci deterministic subwavelength hole arrays fabricated in metal foils, we find that the surface plasmon-polariton (SPP) correlation lengths for aperiodic resonances are smaller than those associated with the underlying grid. The enhanced transmission spectra associated with these arrays contain two groups of Fano-type resonances: those related to the two-dimensional Fibonacci structure and those related to the underlying hole grid array upon which the aperiodic Fibonacci array is built. For both groups the destructive interference frequencies at which transmission minima occur closely match prominent reciprocal vectors in the hole array (HA) structure-factor in reciprocal space. However the Fibonacci-related transmission resonances are much weaker than both their calculated Fourier intensity in k space and the grid-related resonances. These differences may arise from the complex, multi-fractal dispersion relations and scattering from the underlying grid arrays. We also systematically studied and compared the transmission resonance strength of Fibonacci HA and periodic HA lattices as a function of the number of holes in the array structure. We found that the Fibonacci-related resonance strengths are an order of magnitude weaker than that of the periodic HA, consistent with the smaller SPP correlation length for the aperiodic structure. PMID:22772220

Nguyen, Tho Duc; Nahata, Ajay; Vardeny, Z Valy

2012-07-01

7

Measurement of the magneto-optical correlation length in turbid media  

NASA Astrophysics Data System (ADS)

In multiple light scattering media, magnetic field induced circular birefringence (Faraday effect) influences interference effects such as speckle pattern or coherent backscattering. It was predicted that in the diffusive regime the relevant correlation length with respect to the Faraday rotation l*F differs, in general, from the transport mean free path l*. We have experimentally verified the prediction that the ratio l*F/l* equals 2 for Rayleigh scattering and decreases to 1 with increasing scatterer size. We also discuss the influence of the structure factor on l*F.

Lenke, Ralf; Eisenmann, Christoph; Reinke, Daniel; Maret, Georg

2002-11-01

8

Correlation Lengths and Measurement Uncertainties from Analysis of Historical Ozonesonde Data in North America and Europe  

NASA Astrophysics Data System (ADS)

A spatial and temporal correlation analysis is performed on WOUDC (World Ozone Data Centre) ozonesonde data for 13 stations at mid-latitudes in North America and Europe. As much as 40 years of data is available for some stations. After removal of the seasonal cycle and periodic variations such as the QBO, as well as of long- term trends, spatial correlation (relative to other stations) coefficients and auto-correlation coefficients are calculated. Ozone partial pressure data at 1 km altitude resolution are used. The auto-correlation function appears to drop rapidly within few days, and the spatial correlation decreases with the distance between stations. The distance for the spatial correlation coefficient to decrease by 1/e is about 1000-2000 km in the stratosphere with a peak at around 22 km, and 500-1000 km in the troposphere. If the calculated values of the correlation coefficient with space (or time) are fitted to an exponential function, the extrapolation of this function to zero distance (or time) provides an estimate of the ozonesonde measurement uncertainty. The ozonesonde uncertainty is found to be less than 7% for altitudes in the 20-30 km range. In the troposphere the uncertainty is about 15% , with higher values in the boundary layer and near the tropopause. These results are broadly consistent with those from the recent JOSIE and BESOS field experiments (Smit et al., 2007; Deshler et al., 2007). If the profiles are normalized to total ozone measurements, the uncertainties decrease by few percent at altitudes higher than 20 km.

Liu, G.; Tarasick, D. W.; Fioletov, V. E.

2007-12-01

9

Measuring Thermodynamic Length  

NASA Astrophysics Data System (ADS)

Thermodynamic length is a metric distance between equilibrium thermodynamic states. Among other interesting properties, this metric asymptotically bounds the dissipation induced by a finite time transformation of a thermodynamic system. It is also connected to the Jensen-Shannon divergence, Fisher information, and Rao’s entropy differential metric. Therefore, thermodynamic length is of central interest in understanding matter out of equilibrium. In this Letter, we will consider how to define thermodynamic length for a small system described by equilibrium statistical mechanics and how to measure thermodynamic length within a computer simulation. Surprisingly, Bennett’s classic acceptance ratio method for measuring free energy differences also measures thermodynamic length.

Crooks, Gavin E.

2007-09-01

10

Measuring Thermodynamic Length  

SciTech Connect

Thermodynamic length is a metric distance between equilibrium thermodynamic states. Among other interesting properties, this metric asymptotically bounds the dissipation induced by a finite time transformation of a thermodynamic system. It is also connected to the Jensen-Shannon divergence, Fisher information, and Rao's entropy differential metric. Therefore, thermodynamic length is of central interestin understanding matter out of equilibrium. In this Letter, we will consider how to denethermodynamic length for a small system described by equilibrium statistical mechanics and how to measure thermodynamic length within a computer simulation. Surprisingly, Bennett's classic acceptance ratio method for measuring free energy differences also measures thermodynamic length.

Crooks, Gavin E

2007-09-07

11

Sprint performance of phrynosomatid lizards, measured on a high-speed treadmill, correlates with hindlimb length  

Microsoft Academic Search

We measured sprint performance of phrynosomatid lizards and selected outgroups (n = 27 species). Maximal sprint running speeds were obtained with a new measurement technique, a high-speed treadmill (H.S.T.). Animals were measured at their approximate field-active body temperatures once on both of 2 consecutive days. Within species, individual variation in speed measurements was consistent between trial days and repeatabilities were

Kevin E. Bonine

1999-01-01

12

Development of Patterns for Digital Image Correlation Measurements at Reduced Length Scales  

Microsoft Academic Search

Methods for patterning metal thin films at the microscale and nanoscale by applying the patterns to metallic and polymeric\\u000a materials for use in shape and deformation measurements in a scanning electron microsope (SEM) or other high magnification\\u000a imaging system are described. In one approach, thin films of metallic materials (e.g., Au, Ag, Cu, and Cr) are applied to\\u000a a variety

W. A. Scrivens; Y. Luo; M. A. Sutton; S. A. Collette; M. L. Myrick; P. Miney; P. E. Colavita; A. P. Reynolds; X. Li

2007-01-01

13

Measuring Crack Length in Coarse Grain Ceramics  

NASA Technical Reports Server (NTRS)

Due to a coarse grain structure, crack lengths in precracked spinel specimens could not be measured optically, so the crack lengths and fracture toughness were estimated by strain gage measurements. An expression was developed via finite element analysis to correlate the measured strain with crack length in four-point flexure. The fracture toughness estimated by the strain gaged samples and another standardized method were in agreement.

Salem, Jonathan A.; Ghosn, Louis J.

2010-01-01

14

Correlation of Choroidal Thickness and Volume Measurements with Axial Length and Age Using Swept Source Optical Coherence Tomography and Optical Low-Coherence Reflectometry  

PubMed Central

Purpose. To report choroidal thickness and volume in healthy eyes using swept source optical coherence tomography (SS-OCT). Methods. A prospective observational study of 122 patients examined with swept source OCT (DRI-OCT, Topcon, Japan). In each eye, we performed 256 horizontal scans, 12?mm in length and centered on the fovea. We calculated choroidal thickness manually with a built-in caliper and automatically using DRI-OCT mapping software. Choroidal volume was also automatically calculated. We measured axial length with optical low-coherence reflectometry (Lenstar LS 900, Haag-Streit, Switzerland). Results. The choroid has focally increased thickness under the fovea. Choroid was thinnest in the outer nasal quadrant. In stepwise regression analysis, age was estimated as the most significant factor correlating with decreased choroidal thickness (F = 23.146, P < 0.001) followed by axial length (F = 4.902, P = 0.03). Refractive error was not statistically significant (F = 1.16, P = 0.28). Conclusions. SS-OCT is the first commercially available system that can automatically create choroidal thickness and volume maps. Choroidal thickness is increased at the fovea and is thinnest nasally. Age and axial length are critical for the estimation of choroidal thickness and volume. Choroidal measurements derived from SS-OCT images have potential value for objectively documenting disease-related choroidal thickness abnormalities and monitoring progressive changes over time.

Michalewski, Janusz; Nawrocka, Zofia; Bednarski, Maciej; Nawrocki, Jerzy

2014-01-01

15

Turbulent Radial Correlation Lengths in the DIII-D Tokamak.  

National Technical Information Service (NTIS)

Measurements of the radial correlation length Ar of density fluctuations have been made on the DIII-D tokamak in a variety of L-mode discharges. These measurements span the radial region 0.5 < (rho) < or = 1 and are found to scale approximately as (rho)(s...

T. L. Rhodes J. N. Leboeuf R. Sydora E. J. Doyle R. A. Moyer

2000-01-01

16

NMR Measures of Heterogeneity Length  

NASA Astrophysics Data System (ADS)

Advanced solid state NMR spectroscopy provides a wealth of information about structure and dynamics of complex systems. On a local scale, multidimensional solid state NMR has elucidated the geometry and the time scale of segmental motions at the glass transition. The higher order correlation functions which are provided by this technique led to the notion of dynamic heterogeneities, which have been characterized in detail with respect to their rate memory and length scale. In polymeric and low molar mass glass formers of different fragility, length scales in the range 2 to 4 nm are observed. In polymeric systems, incompatibility of backbone and side groups as in polyalkylmethacrylates leads to heteogeneities on the nm scale, which manifest themselves in unusual chain dynamics at the glass transition involving extended chain conformations. References: K. Schmidt-Rohr and H.W. Spiess, Multidimensional Solid-State NMR and Polymers,Academic Press, London (1994). U. Tracht, M. Wilhelm, A. Heuer, H. Feng, K. Schmidt-Rohr, H.W. Spiess, Phys. Rev. Lett. 81, 2727 (1998). S.A. Reinsberg, X.H. Qiu, M. Wilhelm, M.D. Ediger, H.W. Spiess, J.Chem.Phys. 114, 7299 (2001). S.A. Reinsberg, A. Heuer, B. Doliwa, H. Zimmermann, H.W. Spiess, J. Non-Crystal. Solids, in press (2002)

Spiess, Hans W.

2002-03-01

17

Leg-length discrepancy measured by ultrasonography.  

PubMed

Leg-length discrepancy was determined by real-time ultrasonography (ultrasound) in 45 patients, and the measurements were compared with those of erect-posture radiography. A special device for holding and moving the ultrasound transducer was constructed, and the leg length was measured as the highest level of the femoral head in the standing position. The correlation coefficient r between ultrasound and radiography was 0.94, the mean difference was -1.9 mm, and the limits of agreement (mean +/- 2 SD) were -9.1 to 5.3 mm. The mean difference between examiners 1 and 2 was 1.7 mm, and the 95 percent confidence interval was +/- 7 mm. We conclude that leg-length discrepancy can be reliably determined by ultrasound, although the accuracy is less than that obtained by radiographic methods. Because ultrasound is not limited by radiation hazards, our technique can be used for clinical screening. PMID:2014720

Terjesen, T; Benum, P; Rossvoll, I; Svenningsen, S; Fløystad Isern, A E; Nordbø, T

1991-04-01

18

Fluorescence Correlation Spectroscopy Measurements of the Membrane Protein TetA in Escherichia coli Suggest Rapid Diffusion at Short Length Scales  

PubMed Central

Structural inhomogeneities in biomembranes can lead to complex diffusive behavior of membrane proteins that depend on the length or time scales that are probed. This effect is well studied in eukaryotic cells, but has been explored only recently in bacteria. Here we used fluorescence recovery after photobleaching (FRAP) and fluorescence correlation spectroscopy (FCS) to study diffusion of the membrane protein TetA-YFP in E. coli. We find that the diffusion constant determined from FRAP is comparable to other reports of inner membrane protein diffusion constants in E. coli. However, FCS, which probes diffusion on shorter length scales, gives a value that is almost two orders of magnitude higher and is comparable to lipid diffusion constants. These results suggest there is a population of TetA-YFP molecules in the membrane that move rapidly over short length scales (? 400 nm) but move significantly more slowly over the longer length scales probed by FRAP.

Chow, David; Guo, Lin; Gai, Feng; Goulian, Mark

2012-01-01

19

Fundamental correlation lengths of coherent speckle in medical ultrasonic images  

Microsoft Academic Search

Refinements to previous analyses of the natural correlation lengths within simple images and between images to be compounded are presented. Comparison of theoretical and experimental results show very good agreement for the case of Rayleigh scattering media: the correlation length within a simple image is comparable to the resolution cell size; the correlation length between images to be spatially compounded

R. F. Wagner; M. F. Insana; S. W. Smith

1988-01-01

20

Acyl Chain Length of Phosphatidylserine Is Correlated with Plant Lifespan  

PubMed Central

Plant lifespan is affected by factors with genetic and environmental bases. The laws governing these two factors and how they affect plant lifespan are unclear. Here we show that the acyl chain length (ACL) of phosphatidylserine (PS) is correlated with plant lifespan. Among the detected eight head-group classes of membrane lipids with lipidomics based on triple quadrupole tandem mass spectrometry, the ACL of PS showed high diversity, in contrast to the ACLs of the other seven classes, which were highly conserved over all stages of development in all plant species and organs and under all conditions that we studied. Further investigation found that acyl chains of PS lengthened during development, senescence, and under environmental stresses and that increasing length was accelerated by promoted- senescence. The acyl chains of PS were limited to a certain carbon number and ceased to increase in length when plants were close to death. These findings suggest that the ACL of PS can count plant lifespan and could be a molecular scale ruler for measuring plant development and senescence.

Tian, Xuejun; Li, Weiqi

2014-01-01

21

Ozone Correlative Measurements Workshop  

NASA Technical Reports Server (NTRS)

A study was conducted to determine the necessary parameters for the correlation of data on Earth ozone. Topics considered were: (1) measurement accuracy; (2) equipment considerations (SBUV); and (3) ground based measurements to support satellite data.

Hilsenrath, E. (editor)

1985-01-01

22

Roughness with a finite correlation length in a microtrap  

SciTech Connect

We analyze the effects of roughness in the magnitude of the magnetic field produced by a current carrying microwire, which is caused by the geometric fluctuation of the edge of the wire. The relation between the fluctuation of the trapping potential and the height the atom trap lies above the wire is very well consistent with the experimental data when the colored noise with a finite correlation length is considered. On this basis, we generate the random potential and get the density distribution of the Bose-Einstein condensate (BEC) atoms by solving the Gross-Pitaevskii equation, which coincides well with the experimental image, especially in the number of fragmentations. The results help us further understand the nature of the fluctuation and predict its possible application in the precise measurement.

Wu Muzhi; Zhou Xiaoji; Chen Xuzong [School of Electronics Engineering and Computer Science, Peking University, Beijing 100871 (China); Liu, W. M. [Institute of Physics, Chinese Academy of Sciences, Beijing 100080 (China)

2010-03-15

23

ULTRASHORT ELECTRON BUNCH LENGTH MEASUREMENTS AT DUVFEL.  

SciTech Connect

The DUVFEL electron linac is designed to produce sub-picosecond, high brightness electron bunches for driving a short wavelength FEL. Four experiments have been commissioned to address the challenge of accurately measuring bunch lengths on this timescale. In the frequency domain, a short 12 period undulator is used to produce both off-axis coherent emission and on-axis incoherent single-shot spectra. The total coherent infrared power scales inversely with bunch length and the spectral cutoff is an indication of bunch length. The density of power spikes in the single-shot visible spectrum may also be used to estimate bunch length. In the time domain, the linac accelerating sections and a bending magnet are used to implement the RF-zero phasing method, and a sub-picosecond streak camera is also installed. Beam measurements and comparisons of these methods are reported.

GRAVES, W.S.; CARR, G.L.; DIMAURO, L.F.; DOYURAN, A.; HEESE, R.; JOHNSON, E.D.; NEUMAN, C.; RAKOWSKY, G.; ROSE, J.; RUDATI, J.; SHAFTAN, T.; SHEEHY, B.; SKARITKA, J.; YU, L.H.

2001-06-18

24

Determining Correlation and Coherence Lengths in Turbulent Boundary Layer Flight Data  

NASA Technical Reports Server (NTRS)

Wall pressure data acquired during flight tests at several flight conditions are analysed and the correlation and coherence lengths of the data reported. It is found that the correlation and coherence lengths are influenced by the origin of the structure producing the pressure and the frequency bandwidth over which the analyses are performed. It is shown how the frequency bandwidth biases the correlation length and how the convection of the pressure field might reduce the coherence measured between sensors. A convected form of the cross correlation and cross spectrum is introduced to compensate for the effects of convection. Coherence lengths measured in the streamwise direction appear much longer than expected. Coherent structures detected using the convected cross correlation do not exhibit an exponential coherent power decay.

Palumbo, Dan

2012-01-01

25

The correlation length for interplanetary magnetic field fluctuations  

NASA Technical Reports Server (NTRS)

It is argued that it is appropriate to consider two correlation lengths for interplanetary magnetic field fluctuations. For particles with gyro-radii large enough to encounter and be scattered by large-scale tangential discontinuities in the field (particles with energies greater than or approximately equal to several GeV/nucleon) the appropriate correlation length is simply the mean spatial separation between the discontinuities, L approximately 2 x 10 to the 11th power. Particles with gyro-radii much less than this mean separation (energies less than or approximately equal to 100 MeV/nucleon) appear to be unaffected by the discontinuities and respond only to smaller-scale field fluctuations. For these particles the correlation length is shown to be L approximately 10 to the 10th power cm. With this system of two correlation lengths the cosmic-ray diffusion tensor may be altered from what was predicted by, for example, Jokipii and Coleman, and the objections raised recently by Klimas and Sandri to the diffusion analysis of Jokipii may apply only at relatively low energies (approximately 50 MeV/nucleon).

Fisk, L. A.; Sari, J. W.

1972-01-01

26

Polyelectrolyte persistence length: Attractive effect of counterion correlations and fluctuations  

NASA Astrophysics Data System (ADS)

The persistence length of a single, strongly charged, stiff polyelectrolyte chain is investigated theoretically. Path integral formulation is used to obtain the effective electrostatic interaction between the monomers. We find significant deviations from the classical Odijk, Skolnick and Fixman (OSF) result. An induced attraction between monomers is due to thermal fluctuations and correlations between bound counterions. The electrostatic persistence length is found to be smaller than the OSF value and indicates a possible mechanical instability (collapse) for highly charged polyelectrolytes with multivalent counterions. In addition, we calculate the amount of condensed counterions on a slightly bent polyelectrolyte. More counterions are found to be adsorbed as compared to the Manning condensation on a cylinder.

Ariel, G.; Andelman, D.

2003-01-01

27

Torque correlation length and stochastic twist dynamics of DNA  

NASA Astrophysics Data System (ADS)

We introduce a short correlation length for torque in twisting-stiff biomolecules, which is necessary for the physical property that torque fluctuations be finite in amplitude. We develop a nonequilibrium theory of dynamics of DNA twisting which predicts two crossover time scales for temporal torque correlations in single-molecule experiments. Bending fluctuations can be included, and at linear order we find that they do not affect the twist dynamics. However, twist fluctuations affect bending, and we predict the spatial inhomogeneity of twist, torque, and buckling arising in nonequilibrium "rotor-bead" experiments.

Banigan, Edward J.; Marko, John F.

2014-06-01

28

Characterization of Hydrogen Bond Lengths in Watson–Crick Base Pairs by Cross-Correlated Relaxation  

Microsoft Academic Search

Hydrogen bond lengths in Watson–Crick base pairs can be characterized by cross-correlated relaxation between 1H chemical shift anisotropy and dipole–dipole coupling of 1H and its hydrogen bond acceptor 15N. As a reference, the cross-correlated relaxation between 1H chemical shift anisotropy and dipole–dipole coupling of 1H and its hydrogen bond donor 15N is used. With the two measured cross-correlated relaxation rates,

Roland Riek

2001-01-01

29

Bedside prediction of airway length by measuring upper incisor manubrio-sternal joint length  

PubMed Central

Background: Malpositioning of endotracheal tube may lead to serious complications like endobronchial intubation or accidental extubation. Using anatomical measurements for prediction of airway length would be more practical in resource constrained settings. Materials and Methods: One hundred adult patients of American Society of Anesthesiologists (ASA) grade 1 or 2, without any evidence of difficult airway, were randomly allocated to two cohorts — a model cohort of 70 (50 males) and test cohort of 30 (20 males) subjects. Height, the straight length from the upper incisor to manubrio-sternal joint in fully extended head position (IncManustL), the length from upper incisor to the carina in neutral head position (IncCarinaL), and degree of neck extension were measured in all subjects. Relationship between the two lengths in the model cohort was explored by Pearson's coefficient (r). Predictions were made for subjects in the test cohort and actual and predicted values assessed for agreement using intra-class correlation coefficient (ICC). Results: Good agreement was found between IncManustL and IncCarinaL for both male (r = 0.69) and female (r = 0.54) subjects. Multiple regression analysis suggested height to be another significant predictor, unlike age, weight, and neck extension. The gender-specific regression equations were used to predict IncCarinaL for the test cohort. ICC for absolute agreement between the actual and predicted values was 0.723 (95% CI 0.495-0.858). Conclusions: It is possible to predict airway length in adult Indian subjects by making two simple anatomical measurements, namely stature and incisor manubrio-sternal joint length.

Mukherjee, Sudipta; Ray, Manjushree; Pal, Rita

2014-01-01

30

Cross correlation and length scales in turbulent flows near surfaces  

NASA Technical Reports Server (NTRS)

Two kinds of length scales are used in turbulent flows; 'functional length scales' such as mixing length, dissipation length L(sub epsilon), etc., and 'flow-field length scales' derived from cross correlations of velocity, pressure, etc. in the flow. Some connection between these scales are derived here. We first consider the cross correlation R(sub vv)(y,y(sub 1)) of the normal components u at two heights y, y(sub 1) above a rigid surface, normalized by the velocity y(sub 1) (greater than y). For shear-free boundary layers it is found theoretically, and in field and numerical experiments that R(sub vv) approximately equals y/y(sub 1). For shear layers it is also found that R(sub vv) approximately equals f(y/y(sub 1)) less than or equal to y,y(sub 1). This function f differs slightly between low Reynolds number numerical simulations and field experiments. The lateral structure defined by R(sub vv)(y,r(sub 3); y(sub 1),0) is also self similar and shows that the eddies centered at about y(sub 1) appear to have constant lateral width a(sub 3) above and below y(sub 1), where a(sub 3, sup +) approximately equals 7+1/(1.4dU(sup +)/dy(sup +)), when normalized on u(sub *) and v, where U is the mean velocity. Results for L(sub epsilon, sup -1) from direct numerical simulation are found to compare well with the formula L(sub epsilon, sup -1) = A(sub B)/y + A(sub S)dU/dy/v, for unidirectional and reversing turbulent boundary layers and channel flow, except near where dU/dy approximately equals 0. The conclusion is that the large-scale eddy structure and length scales in these flows are determined by a combination of shear and blocking, and that the vertical component of turbulence has a self-similar structure in both kinds of boundary layer.

Hunt, J. C. R.; Moin, P.; Lee, M.; Moser, R. D.; Spalart, P.; Mansour, N. N.; Kaimal, J. C.; Gaynor, E.

1989-01-01

31

The Turbulent Correlation Length in the Distant Solar Wind  

NASA Astrophysics Data System (ADS)

A model of turbulent evolution in the distant solar wind has recently been presented which incorporates the detailed quasilinear generation of fluctuations by interstellar pickup protons to drive the turbulence [Isenberg et al., ApJ, 592, 564, 2003; Isenberg, ApJ, submitted, 2004]. The dissipation of the turbulent fluctuations at the standard Kolmogorov rate has been shown to provide a reasonable agreement with observed heating of the core solar wind protons out to almost 75 AU [Smith et al., ApJ, submitted, 2004]. In this model, the correlation length of the turbulence ? (r) is a fundamental quantity, since it controls the turbulent dissipation rate. Although analysis of observations out to 30 AU indicates that ? steadily increases with r, the model calls for this quantity to decrease beyond about 10 AU due to the turbulent driving by the pickup protons. Here, we investigate modifications to the present model which will bring the correlation length more in line with the observations. These modifications will, in turn, affect the predicted turbulent intensities and solar wind temperatures. We will present and discuss the modified model and compare its results with solar wind observations.

Isenberg, P. A.; Smith, C. W.

2004-12-01

32

Relating Vegetation Aerodynamic Roughness Length to Interferometric SAR Measurements  

NASA Technical Reports Server (NTRS)

In this paper, we investigate the feasibility of estimating aerodynamic roughness parameter from interferometric SAR (INSAR) measurements. The relation between the interferometric correlation and the rms height of the surface is presented analytically. Model simulations performed over realistic canopy parameters obtained from field measurements in boreal forest environment demonstrate the capability of the INSAR measurements for estimating and mapping surface roughness lengths over forests and/or other vegetation types. The procedure for estimating this parameter over boreal forests using the INSAR data is discussed and the possibility of extending the methodology over tropical forests is examined.

Saatchi, Sassan; Rodriquez, Ernesto

1998-01-01

33

Automatic detection and measurement of femur length from fetal ultrasonography  

NASA Astrophysics Data System (ADS)

Femur bone length is used in the assessment of fetal development and in the prediction of gestational age (GA). In this paper, we present a completely automated two-step method for identifying fetal femur and measuring its length from 2D ultrasound images. The detection algorithm uses a normalized score premised on the distribution of anatomical shape, size and presentation of the femur bone in clinically acceptable scans. The measurement process utilizes a polynomial curve fitting technique to determine the end-points of the bone from a 1D profile that is most distal from the transducer surface. The method has been tested with manual measurements made on 90 third trimester femur images by two radiologists. The measurements made by the experts are strongly correlated (Pearson's coefficient = 0.95). Likewise, the algorithm estimate is strongly correlated with expert measurements (Pearson's coefficient = 0.92 and 0.94). Based on GA estimates and their bounds specified in Standard Obstetric Tables, the GA predictions from automated measurements are found to be within +/-2SD of GA estimates from both manual measurements in 89/90 cases and within +/-3SD in all 90 cases. The method presented in this paper can be adapted to perform automatic measurement of other fetal limbs.

Mukherjee, Prateep; Swamy, Gokul; Gupta, Madhumita; Patil, Uday; Krishnan, Kajoli Banerjee

2010-03-01

34

Correlation of Head Circumference and Crown-Rump Length in Newborn Infants  

Microsoft Academic Search

A study of 305 consecutive neonatal autopsies done by two prosectors showed a high correlation between the head circumference (HC) and crown-rump length (CR). The calculated formula can be stated approximately as HC = 0.9 CR + 2.5 cm, and the two measurements are for all practical purposes equal in the immediate neonatal period, regardless of race, sex, age and

S.-S. Yang; Y.-C. Chen; A. J. Brough; J. Bernstein

1975-01-01

35

Knee–heel length measurement in healthy preterm infants  

Microsoft Academic Search

AIMTo examine the reproducibility of crown–heel length measurement; the precision and reproducibility of knee–heel length measurement; and the association between the two in healthy preterm infants.METHODSPaired crown–heel and knee–heel lengths were measured on 172 occasions by three observers in 43 preterm infants between 205 and 458 days of postconceptional age.RESULTSCrown–heel length (CHL) measurement was highly reproducible, with a coefficient of

Ian J Griffin; Naomi M Pang; Jeffery Perring; Richard J Cooke

1999-01-01

36

Is there a correlation between right bronchus length and diameter with age?  

PubMed Central

Objective Right main bronchial anatomy knowledge is essential to guide endoscopic stent placement in modern era. The aim is to describe right bronchial anatomy, cross-area and its relation with the right pulmonary artery and patient’s age. Methods One hundred thirty four cadaveric specimens were studied after approval by the Research and Ethics Committee at the University of São Paulo Medical School and Medical Forensic Institute of São Paulo. All necropsies were performed in natura after 24 hours of death and patients with previous pulmonary disease were excluded. Landmarks to start measurement were the first tracheal ring, vertex of carina, first right bronchial ring, and right pulmonary artery area over the right main bronchus. After mobilization, the specimens were measured using a caliper and measurement of distances was recorded in centimeters at landmarks points. All the measures (distances, cross sectional area and planes) were performed by three independent observers and recorded as mean, standard error and ranges. Student t test was used to compare means and linear regression was applied to correlate the measurements. Results From 134 specimens studied, 34 were excluded (10 with previous history of pulmonary diseases, surgery or deformities and 24 of female gender). Linear regression showed proportionality between tracheal length and right bronchus length; with the area at first tracheal ring and carina and also between the cross sectional area at these points. Linear regression analysis between tracheal length and age (R=0.593 P<0.005), right bronchus length and age (R=0.523, P<0.005), area of contact between right bronchus and right pulmonary artery and age (R=0.35, P<0.005). Conclusions We can conclude that large airways grow progressively with increasing age in male gender. There was a direct correlation between age and tracheal length; as has age and right bronchus length. There was a direct correlation between age and the area of the right bronchus covered by the right pulmonary artery.

Otoch, Jose Pinhata; Minamoto, Helio; Perini, Marcos; Carneiro, Fred Olavo

2013-01-01

37

Histomorphometric Study of the Root Apex of Mandibular Premolar Teeth: An Attempt to Correlate Working Length Measured with Electronic and Radiograph Methods to Various Anatomic Positions in the Apical Portion of the Canal  

Microsoft Academic Search

One aim of this study was to attempt to relate the position of the cementodentinal junction (CDJ) and the apical constriction to that of the apical foramen in mandibular premolars, as well as to measure the canal diameter at these various points. Another aim was to evaluate how electronic working length determination by Root ZX and radiographic method of working

Ehab E. Hassanien; Abeer Hashem; Henry Chalfin

2008-01-01

38

Error correction technology of the length grating measuring system  

NASA Astrophysics Data System (ADS)

The resolution of the current length grating measuring system can reach micron level, sub-micron level and nanometer level. Researching and producing the high-resolution and high-preciseness length grating measuring system is the development tendency of measuring technology, while the high-preciseness length grating measuring system also has wide application prospects. In the practical application of the grating system, the error correction technology directly affects the measurement preciseness of the length grating measuring system. Therefore, launching the research on the error correction technology of the length grating measuring system is the important. The correction method of the length grating measuring system is discussed. In the method, the displacement length is traced back to the laser wavelength via the photoelectric microscope, line scale, laser Interferometer and data-fitting tool. The error correction method of the length grating measuring system mentioned in this article is simple in principle, more convenient to be implemented, provides high correction precision, and also can be implemented in real-time automatic correction. For some instruments, based on the length grating measuring such as three-coordinate measuring machine, length measuring machine and so on, the method is of important reference and consultation value.

Shu, Xiaomei; Zuo, Yong; Xu, Xiaobo

2010-08-01

39

Focal Length Measurements for the National Ignition Facility Large Lenses  

SciTech Connect

The focal length of the spatial filter and final focus lenses for the National Ignition Facility are measured to < {+-} 0.01% using a combination of master lenses and production-oriented techniques for relative focal length.

Parham, T G; McCarville, T J; Johnson, M A; Kiikka, C

2002-01-25

40

Clocks for Length and Time Measurement  

Microsoft Academic Search

The evolution of various fields of science, technology, trade or legal metrology is intimately connected with the ability\\u000a to relate measurements with each other that were performed at different places and different instants of time. For this purpose\\u000a a practical system of units of measurement i.e. the International System of Units (SI) has been established by international\\u000a cooperation [1]. In

Fritz Riehle

2001-01-01

41

50 CFR Appendix C to Part 622 - Fish Length Measurements  

Code of Federal Regulations, 2013 CFR

...and Fisheries 12 2013-10-01 2013-10-01 false Fish Length Measurements C Appendix C to Part 622 Wildlife and...SOUTH ATLANTIC Pt. 622, App. C Appendix C to Part 622âFish Length Measurements ER17AP13.000...

2013-10-01

42

The correlation length amplitude for eight-arm star polystyrene in methylcyclohexane near the critical point  

NASA Astrophysics Data System (ADS)

The turbidity of eight-arm star polystyrene in methylcyclohexane has been measured and used to determine the correlation length amplitude ?0 for different molecular weight polystyrene. The turbidity in this system was determined from the measured ratio of the transmitted to incident light intensities over three decades in reduced temperature. Using Ornstein-Zernike theory, we are able to fit the turbidity data and determine that ?0 increases systematically for this branched polystyrene in much the same way as a linear polystyrene of the same molecular weight. We acknowledge the support from NSF-REU grant DMR 0243811 and the donors of the American Chemical Society Petroleum Research Fund.

Brinck, Andy P.; Venkataraman, Nithya L.; Jacobs, D. T.

2004-03-01

43

From Concrete to Abstract in the Measurement of Length  

NASA Astrophysics Data System (ADS)

The concatenation of units of length is widely viewed as the paradigmatic expression of fundamental measurement. Survey, assessment, and test scores in educational and psychological measurement are often interpreted in ways that assume a concatenation of units to have been established, even though these assumptions are rarely stated or tested. A concatenation model for measurement is shown to be equivalent to a Rasch model: any two units of measurement placed end to end must together be of the same length as either one of them added to itself. This additive principle and a concatenation model of measurement together serve as a heuristic guide for organizing two experimental approaches to calibrating instruments for measuring length. The capacity to reproduce the unit of measurement from theory with no need for repeated empirical calibration experiments, as in the geometrical bisection of the line and the resultant halving of the length measure, is highlighted as essential to demonstrating a thorough understanding of the construct.

Stephanou, Andreas; Fisher, William P., Jr.

2013-09-01

44

Measuring Adolescent Boys' Physical Activity: Bout Length and the Influence of Accelerometer Epoch Length  

PubMed Central

Objectives Accurate, objective measurement is important for understanding adolescents' physical activity (PA) behaviour. When using accelerometry to objectively measure PA, a decision must be made regarding how frequently data is recorded (i.e., epoch length). The purpose of this study was to examine i) PA bout length, and ii) the effect of variations in accelerometer epoch length on PA estimates during physical education (PE) and leisure time in adolescent boys. Design Cross-sectional study. Methods Year 9 boys (N?=?133; mean age ±SD ?=?14.36±0.48 years) wore accelerometers during two PE lessons, and for a period of seven consecutive days. Data were reintegrated from 1s into longer periods of 2, 5, 10, 30, and 60 seconds. ANOVAs were used to test for differences in PA estimates between epochs in leisure time and PE. Results The mean length of vigorous PA (VPA) bouts was 3.5±2.0 seconds for PE and 2.5±1.7 seconds for leisure time, and mean length of moderate PA (MPA) bouts was 2.3±0.5 seconds for PE and 2.9±0.5 seconds for leisure time. During PE, estimates of MVPA, MPA, and light PA (LPA) increased as epoch increased from 1 second to 60 seconds, while VPA and sedentary behaviour estimates decreased. During leisure time, estimates of all PA intensities decreased as epoch increased from 1 second to 60 seconds, with the exception of sedentary behaviour, which increased as epoch length increased. Conclusion The context in which PA occurs can influence PA bout length measurement and the effect of variations in epoch length on PA estimates. Researchers measuring PA with accelerometry should be conscious of the possible influence of context on PA estimates.

Sanders, Taren; Cliff, Dylan P.; Lonsdale, Chris

2014-01-01

45

Statistical length measurement method by direct imaging of carbon nanotubes.  

PubMed

The influence of carbon nanotube (CNT) length on their macroscopic properties requires an accurate methodology for CNT length measurement. So far, existing techniques are limited to short (less than a few micrometers) CNTs and sample preparation methods that bias the measured values. Here, we show that the average length of carbon nanotubes (CNTs) can be measured by cryogenic transmission electron microscopy (cryo-TEM) of CNTs in chlorosulfonic acid. The method consists of dissolving at low concentration CNTs in chlorosulfonic acid (a true solvent), imaging the individual CNTs by cryo-TEM, and processing and analyzing the images to determine CNT length. By measuring the total CNT contour length and number of CNT ends in each image, and by applying statistical analysis, we extend the method to cases where each CNT is long enough to span many cryo-TEM images, making the direct length measurement of an entire CNT impractical. Hence, this new technique can be used effectively to estimate samples in a wide range of CNT lengths, although we find that cryo-TEM imaging may bias the measurement towards longer CNTs, which are easier to detect. Our statistical method is also applied to AFM images of CNTs to show that, by using only a few AFM images, it yields estimates that are consistent with literature techniques, based on individually measuring a higher number of CNTs. PMID:24773046

Bengio, E Amram; Tsentalovich, Dmitri E; Behabtu, Natnael; Kleinerman, Olga; Kesselman, Ellina; Schmidt, Judith; Talmon, Yeshayahu; Pasquali, Matteo

2014-05-14

46

Determination of effective correlation length in a glassy polymer using electrostatic force microscopy  

NASA Astrophysics Data System (ADS)

Various fourth-order correlation functions have been used to study the size of dynamically correlated regions in colloidal glasses and simulated glass forming liquids or polymers. However, measuring these correlation functions in molecular glasses has been limited by the small length scales on which the dynamics occur. Electrostatic force microscopy techniques are employed here to probe dielectric noise in polyvinyl acetate. We analyze fourth-order statistical fluctuations in order to determine spatio-temporal correlation lengths and their temperature dependence near the sample's glass transition. The first harmonic response of an applied AC voltage between the conducting AFM tip and the conducting substrate beneath the thin film polymer sample is proportional to the local electric polarization. Noise in this signal is examined and many hours are recorded at various temperatures in order to improve statistical precision. We employ a variety of statistical analysis techniques ranging from power spectrum analysis to variance of autocorrelation functions in order to find deviations from Gaussian statistics. Super-sharp carbon nanotube EFM tips (nominal radius of 10 nm) are employed to probe smaller effective volumes and thus more easily detect these fluctuations.

Rumberger, Brant; Israeloff, Nathan

2012-02-01

47

Manometric measurement of human sphincter of Oddi length.  

PubMed Central

Length of biliary (CBD) and/or pancreatic (PD) sphincter of Oddi (SO) was measured during perendoscopic or intraoperative manometry in 21 control subjects and in 46 patients with biliary disease. When the high resting pressure (HPZ) and the phasic wave zone (PAZ) were considered, SO length was, in the control group, 9.5 +/- 0.5 mm (M +/- SE) and 9.4 +/- 0.6 mm at the level of the CBD-SO, and 7.7 +/- 0.6 mm and 6.9 +/- 0.5 mm at the level of the PD-SO. The physiological sphincter length appeared substantially shorter than the anatomical one, as reported in the literature. No significant differences were found between controls and patients with CBD stones. Endoscopic sphincterotomy without manometry reduced mean sphincter length length of the sphincterotomy was tailored to the manometric findings. Surgical partial sphincterotomy reduced sphincter length by only 46.7 +/- 10.3%.

Habib, F I; Corazziari, E; Biliotti, D; Primerano, L; Viscardi, A; Speranza, V; De Masi, E; Fegiz, G; Torsoli, A

1988-01-01

48

Run-Length Distributions of Special-Cause Control Charts for Correlated Processes  

Microsoft Academic Search

We derive run-length distributions of the special-cause control chart proposed by Alwan and Roberts for correlated observations, given that the assignable cause to be detected is a shift in the process mean. Both recursive and closed-form solutions are derived for the run-length distribution, average run length (ARL), and standard deviation of the run length (SRL) for any AR(p) process, and

Don G. Wardell; Herbert Moskowitz; Robert D. Plante

1994-01-01

49

The feather-length of small passerines: a measurement for wing-length in live birds and museum skins  

Microsoft Academic Search

Wing-length is difficult to measure reproducibly, and to compare between live birds and museum skins. Recently the length of Primary 8 was suggested as a measure of wing-length in live small passerines; smaller variation was found between observers than in wing-length.This paper examines which feather-length out of Primaries 1 and 6–¸9 best represents wing-length in 51 passerine species. It was

Lukas Jenni; Rafael Winkler

1989-01-01

50

Effective length measurements of prototype Main Injector Dipole endpacks  

SciTech Connect

An endpack design has been developed for the Fermilab Main Injector Dipole. A major part of the design process was the testing of a series of prototype removable endpacks. The magnetic parameters that were tested included the effective length and the field shape variation. This report presents a description of the measurement techniques and the results for the effective length. The final endpack has an effective length at 1500 A (0.29T) of 2.6 [plus minus] 0.3 mm greater than the steel length, and the change in effective length from 1500 A to maximum current of 9500 A (1.74T) is [minus]1.88 [plus minus] 0.05 mm.

Glass, H.D.; Brown, B.C.; Harding, D.J.

1993-03-03

51

Effective length measurements of prototype Main Injector Dipole endpacks  

SciTech Connect

An endpack design has been developed for the Fermilab Main Injector Dipole. A major part of the design process was the testing of a series of prototype removable endpacks. The magnetic parameters that were tested included the effective length and the field shape variation. This report presents a description of the measurement techniques and the results for the effective length. The final endpack has an effective length at 1500 A (0.29T) of 2.6 {plus_minus} 0.3 mm greater than the steel length, and the change in effective length from 1500 A to maximum current of 9500 A (1.74T) is {minus}1.88 {plus_minus} 0.05 mm.

Glass, H.D.; Brown, B.C.; Harding, D.J.

1993-03-03

52

Focal length measurement by fiber point diffraction longitudinal interferometry  

NASA Astrophysics Data System (ADS)

A focal length measurement method by fiber point-diffraction longitudinal interferometry is proposed. By applying two different longitudinal displacements for the object point respectively and measuring the corresponding displacements of the image point, the lens focal length is derived by Newton formula. The displacements of the object point are introduced by glass plates with known refractive index and thickness. The corresponding displacements of the image point are measured interfeorometrically based on the modeling of the longitudinal interferometry of two point sources. Experiments and error analysis reveal that this method has an accuracy less than 0.15% under normal laboratory environment.

Chen, Lingfeng; Hao, Jinjian; Chen, Zhipu; Guo, Xiaofei

2014-07-01

53

Correlation length of a near-critical, eight-arm star polystyrene in methylcyclohexane  

NASA Astrophysics Data System (ADS)

The turbidity of monodisperse, eight-arm star polystyrene in methylcyclohexane has been measured near each system's critical point and used to determine the correlation length amplitude ?0 at various molecular weights. The turbidity was determined from the measured ratio of the transmitted to incident light intensities as a function of temperature. Various systematic errors were explored and eliminated in obtaining a value of ?0 for each molecular weight of the branched polystyrene in methylcyclohexane. Ornstein-Zernike theory is used to fit the turbidity data. The values of ?0 and their dependence on molecular weight are comparable to that reported in the literature for a linear polystyrene of the same molecular weight in methylcyclohexane. We acknowledge the support from NSF-REU grant DMR 0243811 and to the donors of the American Chemical Society Petroleum Research Fund.

Timmers, Henry; Suddendorf, Sarah; Triplett, Angie; Venkataraman, Nithya; Jacobs, D. T.

2007-03-01

54

Correlation length of a near-critical, eight-arm star polystyrene in methylcyclohexane  

NASA Astrophysics Data System (ADS)

The turbidity of eight-arm star polystyrene in methylcyclohexane has been measured and used to determine the correlation length amplitude ?0. The turbidity in this system was determined from the measured ratio of the transmitted to incident light intensities as a function of temperature. Various systematic errors were explored and eliminated in obtaining a value of ?0 for this branched polystyrene with a total molecular weight of 228,000. Ornstein-Zernike theory is used to fit the turbidity data. The value of ?0 is comparable to that reported in the literature for a linear polystyrene of the same molecular weight in methylcyclohexane. We acknowledge the support from NSF-REU grant DMR 0243811 and to the donors of the American Chemical Society Petroleum Research Fund.

Triplett, Angie

2005-03-01

55

A derivation of roughness correlation length for parameterizing radar backscatter models  

Microsoft Academic Search

Surface roughness is a key parameter of radar backscatter models designed to retrieve surface soil moisture (hS) information from radar images. This work offers a theory-based approach for estimating a key roughness parameter, termed the roughness correlation length (Lc). The Lc is the length in centimetres from a point on the ground to a short distance for which the heights

M. M. Rahman; M. S. Moran; D. P. Thoma; R. Bryant; E. E. Sano; C. D. Holifield Collins; S. Skirvin; C. Kershner; B. J. Orr

2007-01-01

56

Telomere Length in Elderly Caucasians Weakly Correlates with Blood Cell Counts  

PubMed Central

Background. Age-related decrease in bone marrow erythropoietic capacity is often accompanied by the telomere length shortening in peripheral white blood cells. However, limited and conflicting data hamper the conclusive opinion regarding this relationship. Therefore, the aim of this study was to assess an association between telomere length and peripheral blood cell count parameters in the Polish elderly population. Material and Methods. The substudy included 1573 of 4981 subjects aged 65 years or over, participants of the population-based PolSenior study. High-molecular-weight DNA was isolated from blood mononuclear cells. Telomere length (TL) was measured by QRT-PCR as abundance of telomere template versus a single gene copy encoding acidic ribosomal phosphoprotein P0. Results. Only white blood count (WBC) was significantly different in TL tertile subgroups in all subjects (P = 0.02) and in men (P = 0.01), but not in women. Merely in men significant but weak positive correlations were found between TL and WBC (r = 0.11, P < 0.05) and RBC (r = 0.08, P < 0.05). The multiple regression analysis models confirmed a weak, independent contribution of TL to both RBC and WBC. Conclusions. In the elderly, telomere shortening limits hematopoiesis capacity to a very limited extent.

Witecka, Joanna; Koscinska-Marczewska, Justyna; Szwed, Malgorzata; Owczarz, Magdalena; Mossakowska, Malgorzata; Milewicz, Andrzej; Zejda, Jan; Wiecek, Andrzej

2013-01-01

57

Molecular mass dependence of point-to-set correlation length scale in polymers  

NASA Astrophysics Data System (ADS)

We use a recently proposed metric, termed the point-to-set correlation functions, to probe the molecular weight dependence of the relevant static length scales in glass-forming oligomeric chain liquids of 4, 5, 8, and 10 repeat units. In agreement with the results for simple, monatomic fluids, we find that static length scales of the oligomers increase monotonically when the temperature is lowered towards the glass transition temperature of the fluid. More interestingly, the static length scale increases with increasing chain length. Within the bounds of error in our simulations, the static length scale appears to scale as the radius of gyration of the oligomer, but with a prefactor, which is much larger than unity and which grows with the temperature. The preceding behavior contrasts with the length scales extracted from the radial distribution function of the oligomer system, which is practically independent of the chain length.

Hanson, Ben; Pryamitsyn, Victor; Ganesan, Venkat

2012-08-01

58

Detrending moving-average cross-correlation coefficient: Measuring cross-correlations between non-stationary series  

NASA Astrophysics Data System (ADS)

In the paper, we introduce a new measure of correlation between possibly non-stationary series. As the measure is based on the detrending moving-average cross-correlation analysis (DMCA), we label it as the DMCA coefficient ?(?) with a moving average window length ?. We analytically show that the coefficient ranges between -1 and 1 as a standard correlation does. In the simulation study, we show that the values of ?(?) very well correspond to the true correlation between the analyzed series regardless the (non-)stationarity level. Dependence of the newly proposed measure on other parameters-correlation level, moving average window length and time series length-is discussed as well.

Kristoufek, Ladislav

2014-07-01

59

Measurement of Debye length in laser-produced plasma.  

NASA Technical Reports Server (NTRS)

The Debye length of an expanded plasma created by placing an evacuated chamber with an entrance slit in the path of a freely expanding laser produced plasma was measured, using the slab geometry. An independent measurement of electron density together with the observed value for the Debye length also provided a means for evaluating the plasma electron temperature. This temperature has applications in ascertaining plasma conductivity and magnetic field necessary for confinement of the laser produced plasma. Also, the temperature obtained would be useful in analyzing electron-ion recombination rates in the expanded plasma and the dynamics of the cooling process of the plasma expansion.

Ehler, W.

1973-01-01

60

What can we learn about a dynamical length scale in glasses from measurements of surface mobility?  

NASA Astrophysics Data System (ADS)

We consider the ability of recent measurements on the size of a liquid-like mobile surface region in glasses to provide direct information on the length scale of enhanced surface mobility. While these quantities are strongly related there are important distinctions that limit the ability of measurements to quantify the actual length over which the surface properties change from surface to bulk-like. In particular, we show that for temperatures near the bulk glass transition, measurements of a liquid-like mobile layer may have very limited predictive power when it comes to determining the temperature dependent length scale of enhanced surface mobility near the glass transition temperature. This places important limitations on the ability of measurements of such enhanced surface dynamics to contribute to discussion on the length scale for dynamical correlation in glassy materials.

Forrest, J. A.

2013-08-01

61

Correlation between hybrid layer thickness, resin tag length and microtensile bond strength of a self-etching adhesive system.  

PubMed

The purpose of this study was to evaluate the correlation between the hybrid layer thickness, resin tag length and resin bond strength of a self-etching adhesive system to sound dentin tissue "in vivo". After performing restorative procedures and tooth extractions, ten specimens were sectioned in a mesiodistal direction. One dental section was used for light microscope analysis, in which both the resin tag length and hybrid layer thickness were measured, while the other section was analyzed using a microtensile test (0.5 mm/min). The fractured surface of the latter section was characterized using a stereoscopic magnifying glass (40x magnifcation). The results were subject to statistical analysis using the Pearson Correlation Test (a = 0.05). The hybrid layer thickness, resin tag length and resin bond strength mean values were 2.19 microm (0.34), 4.34 microm (0.28) and 9.73 MPa (5,55), respectively. In addition, correlation tests between the resin tag length and the resin bond strength (r=0.014) and also between the hybrid layer thickness and bond strength (r=0.43), showed no statistically significant correlation. The microtensile bond strength of Adper Prompt L Pop self-etching adhesive system does not depend on hybrid layer thickness or resin tag length. PMID:23230647

Rahal, Vanessa; de Oliveira, Fernanda G; Briso, André L F; dos Santos, Paulo H; Sundefeld, Maria L M M; Sundfeld, Renato H

2012-01-01

62

Using Confined ^4He to Determine the Correlation-Length Exponent  

NASA Astrophysics Data System (ADS)

We have previously measured the specific heat of ^4He confined to six different planar geometries. Finite-size scaling theory predicts this data will collapse to a single locus when appropriately plotted using the bulk correlation length exponent ? (and associated specific heat exponent ? determined from ? using hyper-scaling relations) and the smallest distance between the two confining surfaces. We have previously shown good collapse of the data by fixing the exponent ?=0.6705 and ?=-0.0115. We present here a different analysis in which we use data at all confinements and consider nu as a variational parameter to achieve optimum data collapse. This result is consistent, within the statistical error, with both the best theoretical values for nu and the value which can be obtained from the superfluid density. This work is supported by the National Science Foundation, DMR0242246, and the CNF 526-94.

Kimball, Mark O.; Gasparini, Francis M.

2004-03-01

63

Negative correlation between age of subjects and length of the appendix in Bangladeshi males  

PubMed Central

Introduction The anatomy of the vermiform appendix shows variations in its macroscopic dimensions some of which have potential to influence the clinical aspects of the appendix. Anatomical studies on the appendix using people in Bangladesh as a sample are limited and fall short of producing any standardized anthropometric data. This study is predominantly a cross-sectional observational study which also uses some statistical analysis to understand the relationships amongst variables. Material and methods Fifty-six adult male postmortem appendices and adnexa were examined for macroscopic features. Possible interrelationships among the variables were assessed through statistical analysis. The age of the samples ranged from 18 to 67 years. The most common position of the appendix was retrocolic (53.57%) followed by pelvic (30.35%), postileal (12.5%), and subcaecal (3.5%). Results In most cases (62.5%) the mesoappendix did not reach the tip of the appendix. The appendicular length varied from 6.00 cm to 16.30 cm with mean (± SD) and median value of 10.21 ±2.50 cm and 10.00 cm respectively. The base of the appendix was 1.90 to 3.80 cm away from the ileocaecal junction. The other macroscopic measurements of the appendix were taken at the base, at the midzone and at the tip of the appendix and the mean of the three measurements was considered as the overall value. Thus, the overall external diameter varied between 0.32 cm and 0.83 cm. Assessment of possible correlations amongst different variables revealed a significant negative correlation between the age of the subjects and the length of the appendix. Conclusions The data of the present study may provide a baseline along with some previous data in the standardization of the anthropometric information regarding the vermiform appendix of Bangladeshi males.

Bakar, Sheikh Muhammad Abu; Shamim, Manjare; Alam, Gazi Mahabubul

2013-01-01

64

FEL Gain Length and Taper Measurements at LCLS  

SciTech Connect

We present experimental studies of the gain length and saturation power level from 1.5 nm to 1.5 {angstrom} at the Linac Coherent Light Source (LCLS). By disrupting the FEL process with an orbit kick, we are able to measure the X-ray intensity as a function of undulator length. This kick method is cross-checked with the method of removing undulator sections. We also study the FEL-induced electron energy loss after saturation to determine the optimal taper of the undulator K values. The experimental results are compared to theory and simulations.

Ratner, Daniel; Brachmann, A.; Decker, F.J.; Ding, Y.; Dowell, D.; Emma, P.; Frisch, J.; Gilevich, S.; Hays, G.; Hering, P.; Huang, Z.; Iverson, R.; Loos, H.; Miahnahri, A.; Nuhn, H.D.; Turner, J.; Welch, J.; White, W.; Wu, J.; Xiang, D.; Yocky, G.; /SLAC /LBL, Berkeley; ,

2010-07-30

65

FEL GAIN LENGTH AND TAPER MEASUREMENTS AT LCLS  

SciTech Connect

We present experimental studies of the gain length and saturation power level from 1.5 nm to 1.5 Angstroms at the Linac Coherent Light Source (LCLS). By disrupting theFEL process with an orbit kick, we are able to measure the X-ray intensity as a function of undulator length. This kick method is cross-checked with the method of removing undulator sections. We also study the FEL-induced electron energy loss after saturation to determine the optimal taper of the undulator K values. The experimental results are compared to theory and simulations.

Ratner, D.; Fawley, W. M.; Brachmann, A.; Decker, F.J.; Ding, Y.; Dowell, D.; Emma, P.; Frisch, J.; Gilevich, S.; Hays, G.; Hering, P.; Huang, Z.; Loos, H.; Miahnahri, A.; Nuhn, H.D.; Turner, J.; Welch, J.; White, W.; Wu, J.; Xiang, D.; Yocky, G.; Fawley, W. M.

2009-08-14

66

Effective crack lengths by compliance measurement for ARALL-2 laminates  

NASA Technical Reports Server (NTRS)

As a means of determining a stress intensity factor solution, the compliance properties of an ARALL-2 laminated-sheet composite were investigated. Fatigue crack growth rate (FCGR) tests were conducted on middle crack tension (MT) specimens fabricated from a layup consisting of three sheets of 2024-T3 aluminum bonded together with unidirectional aramid fibers embedded in epoxy. Excellent fatigue crack growth properties are obtained by the presence of unbroken aramid fibers in the wake of the crack tip. These unbroken fibers act as a bridging mechanism to inhibit further crack growth. To quantify the effect of maximum fatigue load on compliance, a series of FCGR tests were performed. Effective crack lengths were determined to be at least 10 mm shorter than surface measured crack lengths for a 76-mm-wide specimen. The bridging zone was estimated to be at least 5 mm. Compliance and stress intensity factor as functions of effective crack length were determined.

Wilson, Christopher D.; Wilson, Dale A.

1991-01-01

67

Novel principle of contactless gauge blocks length measurement  

NASA Astrophysics Data System (ADS)

This paper presents a novel principle for contactless gauge block measurement using a combination of low-coherence interferometry and laser interferometry. The experimental setup combines a Dowell interferometer and a Michelson interferometer to ensure a gauge block length determination with direct traceability to the primary length standard. This setup was designed for contactless complex gauge block analysis providing information about gauge block length, gauge block faces surface profile (e.g., indication of scratches) and by analysis of the interference fringes shape, also about the gauge block edge flatness distortion. The designed setup is supplemented by an automatic handling system designed for a set of 126 gauge blocks (0.5 mm to 100 mm) to allow the automatic contactless calibration of the complex gauge block set without a human operator.

Buchta, Zden?k.; ?e?ucha, Šimon; Mikel, B?etislav; ?ížek, Martin; Lazar, Josef; ?íp, Ond?ej

2012-01-01

68

Effective humidity in length measurements: comparison of three approaches  

NASA Astrophysics Data System (ADS)

Humidity is one of the key atmospheric parameters influencing the refractive index of air. Consequently, humidity influences all length measurements whose scale is derived from the speed of light. In this work, we present two laser spectrometers developed for determining the average humidity of air over a long measurement path where local variations may be difficult to measure using conventional sensors. Further, these laser-based systems allow, in principle, good spatial overlap with the beams used in dimensional measurements. The developed systems were compared to each other and to traceable reference sensors during a 65 h measurement campaign. The performance of the systems was investigated under three different conditions: steady state, humidity transient and temperature transient. Both systems were separately tested in outdoor environment at distances up to several hundreds of metres. The measurement results demonstrate that the systems are able to measure the relative humidity below the 4% uncertainty level both in indoor and in outdoor environment.

Pollinger, Florian; Hieta, Tuomas; Vainio, Markku; Doloca, Nicolae R.; Abou-Zeid, Ahmed; Meiners-Hagen, Karl; Merimaa, Mikko

2012-02-01

69

Correlation length of vorticity in the near wall region of a high Reynolds number boundary layer.  

NASA Astrophysics Data System (ADS)

Time series of the spanwise and wall normal components of vorticity were measured in the near wall region of an atmospheric boundary layer. The measurements were acquired at the SLTEST site located in western Utah during a period of neutral thermal stability. The surface was nearly flat, free of vegetation, with a small scale roughness of approximately 2mm. The measurements were acquired at an elevation of 40cm from the surface, or y+=10,300. The Reynolds number based on momentum thickness was approximately 10^6, with a boundary layer thickness of approximately 200m. The vorticity measurements indicate an extremely long correlation time of the near wall vorticity field. Length scales were calculated assuming a convection velocity equal to the local mean. For example, the first zero of the autocorrelation function of the spanwise component of vorticity was found to be at 40m. The same quantity calculated for the wall normal vorticity component was found to be at 220m. This leads to vorticity spectra which deviate from predictions based on isotropic models at moderate to low wave numbers. These data imply a strong causal relationship between the large motions in the outer region of the boundary layer and the near wall motions. A conceptual understanding of the boundary layer turbulent motions which is consistent with these findings will be discussed.

Morris, Scott C.; Foss, John; Maher, Matthew

2002-11-01

70

Absolute length measurement using manually decided stereo correspondence for endoscopy  

NASA Astrophysics Data System (ADS)

In recent years, various kinds of endoscope have been developed and widely used to endoscopic biopsy, endoscopic operation and endoscopy. The size of the inflammatory part is important to determine a method of medical treatment. However, it is not easy to measure absolute size of inflammatory part such as ulcer, cancer and polyp from the endoscopic image. Therefore, it is required measuring the size of those part in endoscopy. In this paper, we propose a new method to measure the absolute length in a straight line between arbitrary two points based on the photogrammetry using endoscope with magnetic tracking sensor which gives camera position and angle. In this method, the stereo-corresponding points between two endoscopic images are determined by the endoscopist without any apparatus of projection and calculation to find the stereo correspondences, then the absolute length can be calculated on the basis of the photogrammetry. The evaluation experiment using a checkerboard showed that the errors of the measurements are less than 2% of the target length when the baseline is sufficiently-long.

Sasaki, M.; Koishi, T.; Nakaguchi, T.; Tsumura, N.; Miyake, Y.

2009-02-01

71

Interaural correlations in normal and traumatized cochleas: length and sensory cell loss  

SciTech Connect

Sizable intraspecies variations have been found in both the length of the organ of Corti (OC) and the amount of damage resulting from exposure to a particular ototraumatic agent. These variations have made it difficult to address certain research questions such as the susceptibility of the previously injured ear to further damage. If intra-animal correlation is high, the variability problem could be circumvented by using the two ears from a given animal for different aspects of the same study. Therefore, correlation coefficients were calculated for OC length and for percentage of missing inner (IHCs) and outer hair cells (OHCs) in a large sample of chinchillas which included controls and animals which had been exposed to noise or treated with ionizing radiation. The correlation coefficients were +0.96 for OC length, +0.93 for IHC loss, and +0.97 for OHC loss.

Bohne, B.A.; Bozzay, D.G.; Harding, G.W.

1986-12-01

72

Two-Point Velocity Correlation Measurements in an Axisymmetric Sudden Expansion Using LDV.  

National Technical Information Service (NTIS)

Two-point velocity correlation measurements were made in the anisotropic flow field of an axisymmetric sudden expansion using two single component LDV system. Both longitudinal and lateral spatial correlations were measured. The integral length scales and...

R. D. Gould L. H. Benedict A. S. Nejad S. A. Ahmed

1992-01-01

73

Daily energy expenditure of male barn swallows correlates with tail-streamer length: handicap-mediated foraging strategies.  

PubMed

Daily energy expenditure (DEE) of male barn swallows (Hirundo rustica), measured using the doubly labelled water technique, correlated with streamer length. Contrary to predictions derived from previous findings, neither a positive linear nor a u-shaped relationship was found between DEE and streamer length. Instead, an n-shaped curve showed that the highest DEE corresponded to an intermediate streamer length of 119 mm. A model incorporating estimates of resting metabolism and flight energy expenditure from aerodynamics models suggested that variation in individual tail dynamics was the most likely explanation for the observed DEE. We suggest that streamer length is coupled to foraging strategy, because tail dynamics control flight performance, which in turn influences flight behaviour. PMID:15252971

Nudds, Robert L; Spencer, Karen A

2004-05-01

74

The formation of interstellar molecular lines in a turbulent velocity field with finite correlation length  

NASA Astrophysics Data System (ADS)

The authors investigate by means of numerical calculations the formation of interstellar molecular lines in a turbulent velocity field with finite correlation length. They have applied the theory developed by Gail et al. (1975, 1980) to the model of a homogeneous plane parallel slab. They have solved the full NLTE-problem, i.e. the generalized transfer equations simultaneously with the rate equations, the model molecule being a 6-level CO molecule. The results show that a finite correlation length affects strongly the line profiles, the line widths, and the intensity ratios, in particular the ratios of corresponding transitions in different isotopic species.

Albrecht, M. A.; Kegel, W. H.

1987-04-01

75

Absolute Bunch Length Measurements by Incoherent Radiation Fluctuation Analysis  

SciTech Connect

By analyzing the pulse to pulse intensity fluctuations of the radiation emitted by a charge particle in the incoherent part of the spectrum, it is possible to extract information about the spatial distribution of the beam. At the Advanced Light Source (ALS) of the Lawrence Berkeley National Laboratory, we have developed and successfully tested a simple scheme based on this principle that allows for the absolute measurement of the rms bunch length. A description of the method and the experimental results are presented.

Sannibale, F.; /LBL, Berkeley; Stupakov, G.V.; /SLAC; Zolotorev, M.S.; /LBL, Berkeley; Filippetto, D.; /INFN, Rome; Jagerhofer, L.; /Vienna, Tech. U.

2009-12-09

76

Absolute bunch length measurements by incoherent radiation fluctuation analysis  

NASA Astrophysics Data System (ADS)

By analyzing the pulse to pulse intensity fluctuations of the radiation emitted by a charge particle in the incoherent part of the spectrum, it is possible to extract information about the spatial distribution of the beam. At the Advanced Light Source of the Lawrence Berkeley National Laboratory, we have developed and successfully tested a simple scheme based on this principle that allows for the absolute measurement of the rms bunch length. A description of the method and the experimental results are presented.

Sannibale, F.; Stupakov, G. V.; Zolotorev, M. S.; Filippetto, D.; Jägerhofer, L.

2009-03-01

77

Measurement of Correlation-Enhanced Collision Rates  

SciTech Connect

We measure the perpendicular-to-parallel collision rate {nu}{sub perpendicular||} in laser-cooled magnetized ion plasmas, spanning the uncorrelated to correlated regimes. In correlated regimes, we measure collision rates consistent with the 'Salpeter correlation enhancement' of roughly exp({gamma}), for correlation parameters {gamma} < or approx. 4. This enhancement also applies to fusion in dense plasmas such as stars.

Anderegg, F.; Dubin, D. H. E.; O'Neil, T. M.; Driscoll, C. F. [Department of Physics, University of California at San Diego, La Jolla, California 92093 (United States)

2009-05-08

78

Differential length measurement using low coherence coupled tandem interferometry  

NASA Astrophysics Data System (ADS)

This paper presents the use of low coherence coupled tandem interferometry to measure the differential length of two independent Fabry-Perot (F-P) type microcavities. The two discrete F-P type microcavities are formed between the cleaved end of a fibre and a reflective surface, which could for example, be a pressure sensing membrane or any other component of a transducing element. The technique is an all-optical fibre based sensing configuration in which the sensing cavities are at widely separated locations in an environment where strong temperature gradients may exist. The sensing system is based on two sequential cavities arranged in tandem. The lengths of the cavities are probed by a temperature stabilised fibre based Michelson interferometer operating with a broadband light source. One arm of the probing Michelson interferometer is scanned using a piezo fibre stretcher resulting in an optical path length difference (OPD) between the two arms. The optical interconnecting leads from the probing Michelson interferometer to the two F-P locations are not an active part of the sensor configuration and therefore this configuration is largely insensitive to temperature and strain effects on these interconnecting leads. It is only the probing Michelson interferometer which has to be temperature stabilised. This arrangement allows the F-P measurement cavities to be separated by distances in the range of tens of meters.

Smith, Martin D.; MacPherson, William N.; Maier, Robert R. J.

2013-05-01

79

Measurement of radon diffusion length in thin membranes.  

PubMed

Building regulations in Israel require the insulating of buildings against radon (222)Rn penetration from soil. In radon-prone areas membranes stretched between the soil and the building foundation are used, together with sealing other possible penetration routes. Designing the radon mitigation procedure requires checking that all sealing materials are practically, radon tight, having a thickness of at least three times the radon diffusion length. In this work, a very simple technique to evaluate the radon diffusion length in thin membranes, using a radon source of known activity and an activated charcoal canister as radon detector is presented. The theoretical formalism and measurement results for polyethylene membranes of different densities obtained in a recent comparison exercise are presented. PMID:22232779

Malki, A; Lavi, N; Moinester, M; Nassar, H; Neeman, E; Piasetzky, E; Steiner, V

2012-07-01

80

Direct measurement of the formation length of photons.  

PubMed

We report the first observation of a shoulder in the radiation spectrum from GeV electrons in a structured target consisting of two thin and closely spaced foils. The position of the shoulder depends on the target spacing and is directly connected to the finite formation length of a low-energy photon emitted by an ultrarelativistic electron. With the present setup it is possible to control the separation of the foils on a ?m scale and hence measure interference effects caused by the macroscopic dimensions of the formation length. Several theoretical groups have predicted this effect using different methods. Our observations have a preference for the modified theory by Blankenbecler but disagree with the results of Baier and Katkov. PMID:22401193

Andersen, Kristoffer K; Andersen, Søren L; Esberg, Jakob; Knudsen, Helge; Mikkelsen, Rune; Uggerhøj, Ulrik I; Sona, Pietro; Mangiarotti, Alessio; Ketel, Tjeerd J; Ballestrero, Sergio

2012-02-17

81

Correlation of bowel symptoms with colonic transit, length, and faecal load in functional faecal retention  

Microsoft Academic Search

Introduction: Abdominal pain, bloating, and defecation disturbances are common complaints in gastrointestinal functional disorders. This study ex- plores whether bowel symptoms are correlated to colon transit time (CTT), faecal loading (coprostasis), and colon length; and whether prokinetic inter- vention can reduce CTT, faecal retention, and symptoms. Methods: This observational and interventional study includes 281 patients, and 44 asymptomatic controls. Evaluations

Dennis Raahave; Elsebeth Christensen; Franck B. Loud; Lisbet L. Knudsen

82

Interferometric Dispersion Measurements on Short Lengths of Monomode Optical Fibre.  

NASA Astrophysics Data System (ADS)

Available from UMI in association with The British Library. Second and third order dispersion measurements were made on short lengths (~1m) of three types of low birefringence monomode optical fibre using the technique of 'white light' interferometry based upon a Mach Zehnder interferometer. The interferometer output was analysed with a scanning monochromator over the wavelength range 770-910 nm for various optical path length differences. Novel optical and electronic signal processing techniques were developed to improve the stability of the interferometer and hence improve the signal to noise ratio of the measurements. Rigorous analysis of the experimental data using a non linear least squares fitting algorithm combined with statistical tests designed to detect inadequencies in the theoretical functions have resulted in a temporal resolution of 7 times 10 ^{-5}ps/nm in a metre length of fibre. This is equivalent to a second order dispersion resolution of 0.07 ps/nm/km. The third order dispersion resolution was 0.02 ps/nm^2/km. Comparison of the experimental results with the theoretical chromatic dispersion derived from material dispersion, waveguide dispersion and the effect of material dispersion on waveguide dispersion gave excellent agreement. A technique has been developed to measure first order dispersion based on a modified frequency modulated continuous wave (FMCW) radar technique. Novel electronic signal processing was incorporated into the 'white light' interferometric system in order to obtain these measurements. The results were found to be in agreement with those predicted from the physical properties of the test fibres.

Merritt, Paul A.

83

Thin-filament length correlates with fiber type in human skeletal muscle.  

PubMed

Force production in skeletal muscle is proportional to the amount of overlap between the thin and thick filaments, which, in turn, depends on their lengths. Both thin- and thick-filament lengths are precisely regulated and uniform within a myofibril. While thick-filament lengths are essentially constant across muscles and species (?1.65 ?m), thin-filament lengths are highly variable both across species and across muscles of a single species. Here, we used a high-resolution immunofluorescence and image analysis technique (distributed deconvolution) to directly test the hypothesis that thin-filament lengths vary across human muscles. Using deltoid and pectoralis major muscle biopsies, we identified thin-filament lengths that ranged from 1.19 ± 0.08 to 1.37 ± 0.04 ?m, based on tropomodulin localization with respect to the Z-line. Tropomodulin localized from 0.28 to 0.47 ?m further from the Z-line than the NH(2)-terminus of nebulin in the various biopsies, indicating that human thin filaments have nebulin-free, pointed-end extensions that comprise up to 34% of total thin-filament length. Furthermore, thin-filament length was negatively correlated with the percentage of type 2X myosin heavy chain within the biopsy and shorter in type 2X myosin heavy chain-positive fibers, establishing the existence of a relationship between thin-filament lengths and fiber types in human muscle. Together, these data challenge the widely held assumption that human thin-filament lengths are constant. Our results also have broad relevance to musculoskeletal modeling, surgical reattachment of muscles, and orthopedic rehabilitation. PMID:22075691

Gokhin, David S; Kim, Nancy E; Lewis, Sarah A; Hoenecke, Heinz R; D'Lima, Darryl D; Fowler, Velia M

2012-02-01

84

Range of Interaction between DNA-Bending Proteins is Controlled by the Second-Longest Correlation Length for Bending Fluctuations  

NASA Astrophysics Data System (ADS)

When a DNA molecule is stretched, the zero-force correlation length for its bending fluctuations—the persistence length A—bifurcates into two different correlation lengths—the shorter “longitudinal” correlation length ??(f) and the longer “transverse” correlation length ??(f). In the high-force limit, ??(f)=??(f)/2=kBTA/f/2. When DNA-bending proteins bind to the DNA molecule, there is an effective interaction between the protein-generated bends mediated by DNA elasticity and bending fluctuations. Surprisingly, the range of this interaction is not the longest correlation length associated with transverse fluctuations of the tangent vector along the polymer, but instead is the second longest longitudinal correlation length ??(f,?). The effect arises from the protein-bend contribution to the Hamiltonian having an axial rotational symmetry which eliminates its coupling to the transverse fluctuations.

Zhang, Houyin; Marko, John F.

2012-12-01

85

Correlated measurement error hampers association network inference.  

PubMed

Modern chromatography-based metabolomics measurements generate large amounts of data in the form of abundances of metabolites. An increasingly popular way of representing and analyzing such data is by means of association networks. Ideally, such a network can be interpreted in terms of the underlying biology. A property of chromatography-based metabolomics data is that the measurement error structure is complex: apart from the usual (random) instrumental error there is also correlated measurement error. This is intrinsic to the way the samples are prepared and the analyses are performed and cannot be avoided. The impact of correlated measurement errors on (partial) correlation networks can be large and is not always predictable. The interplay between relative amounts of uncorrelated measurement error, correlated measurement error and biological variation defines this impact. Using chromatography-based time-resolved lipidomics data obtained from a human intervention study we show how partial correlation based association networks are influenced by correlated measurement error. We show how the effect of correlated measurement error on partial correlations is different for direct and indirect associations. For direct associations the correlated measurement error usually has no negative effect on the results, while for indirect associations, depending on the relative size of the correlated measurement error, results can become unreliable. The aim of this paper is to generate awareness of the existence of correlated measurement errors and their influence on association networks. Time series lipidomics data is used for this purpose, as it makes it possible to visually distinguish the correlated measurement error from a biological response. Underestimating the phenomenon of correlated measurement error will result in the suggestion of biologically meaningful results that in reality rest solely on complicated error structures. Using proper experimental designs that allow for the quantification of the size of correlated and uncorrelated errors, can help to identify suspicious connections in association networks constructed from (partial) correlations. PMID:24951433

Kaduk, Mateusz; Hoefsloot, Huub C J; Vis, Daniel J; Reijmers, Theo; van der Greef, Jan; Smilde, Age K; Hendriks, Margriet M W B

2014-09-01

86

Choosing an Appropriate Length of Loop Type Ureteral Stent Using Direct Ureteral Length Measurement  

Microsoft Academic Search

Purpose: The ureteral stent is now a fundamental part of many urological procedures. To decrease ureteral stent-related symptoms, loop type ureteral stent was developed. However the most important factor to decrease urinary symptoms is choosing the optimal length of a ureteral stent. We investigated the relationship between the actual ureteral length and the loop type ureteral stent position. Materials and

Takashi Kawahara; Hiroki Ito; Hideyuki Terao; Minoru Yoshida; Takehiko Ogawa; Hiroji Uemura; Yoshinobu Kubota; Junichi Matsuzaki

2012-01-01

87

Axial length measurement techniques in pediatric eyes with cataract  

PubMed Central

Globe axial length (AL) in children is commonly measured using either contact or immersion technique. Office measurement of AL can be difficult in young children and infants and must often be done under anesthesia in an eye that is unable to cooperate with precise fixation and centration. Contact A-scan measurements yield shorter AL, on average, than immersion A-scan measurements in pediatric eyes. This difference is mainly the result of the anterior chamber depth rather than the lens thickness value. During intraocular lens power calculation, if globe axial length is measured by the contact technique, it will result in the use of an average 1-D stronger IOL power than is actually required. This can lead to induced myopia in the postoperative refraction. In our studied patients, there was a significant difference in prediction error between contact A-scan biometry and immersion A-scan biometry. The immersion A-scan technique is recommended for pediatric IOL power calculation. We also provide a review of biometry in pediatric eyes. The overall mean AL of pediatric cataractous eyes is significantly different than the mean AL of non cataractous eyes. More importantly, the standard deviation is higher in eyes with cataract than in those without. Three phases of eye growth in children have been documented: A rapid, postnatal phase from birth to 6 months of age, followed by a slower, infantile phase from 6 to 18 months of age, and finally a slow, juvenile phase from 18 months forward. In our study, girls had shorter ALs than boys and African-American subjects had longer ALs than Caucasians. Eyes with unilateral cataract had shorter ALs than eyes with bilateral cataract during the earlier years, but had longer ALs during later childhood.

Wilson, M. Edward; Trivedi, Rupal H.

2011-01-01

88

Correlation of ion dynamics with characteristic length scales and network structural units in bismuth borate glasses  

NASA Astrophysics Data System (ADS)

Ion dynamics in lithium bismuth borate conducting glasses have been reported in wide composition and temperature ranges. The activation energy for the dc conduction has been analysed using Anderson-Stuart model and a correlation between the dc conductivity and the doorway radius has been predicted. The characteristic length scales for ion dynamics, such as mean square displacement and spatial extent of sub-diffusive motion of lithium ions have been determined from the ac conductivity and dielectric spectra, respectively. A direct connection between the ion dynamics and the characteristic length scales and the network structural units have been established.

Shaw, A.; Ghosh, A.

2013-09-01

89

Measurement of scattering lengths using kaon(pi3) decay  

NASA Astrophysics Data System (ADS)

The determination of N-N and pp scattering lengths is of fundamental importance in the studies of hadron dynamics. A direct measurement of pp scattering lengths is impossible due to a lack of processes with just two pions in both the initial and final state. Therefore indirect methods must be used. In the past, pN-->ppN and Ke4 decay[1] have been employed. These analyses are complicated due to problems of (a)extrapolation to threshold, (b)contribution of higher multipoles, and (c)inelasticity effects. In this thesis we present a novel analysis of stopped K+p3 decays (K+-->p+p0 p0) to deduce the scattering lengths ( a00 and a20 ) in a nearly model independent way. The model of Sawyer and Wali[2], incorporating Chew and Mandelstam's[3] result for pp scattering, was used to analyze the data. The data is a kinematically complete determination of Kp3 decays, a byproduct of the T-violation experiment at KEK[4]. It is fit to an amplitude At' (s1,s2,s3 )=- 2lp( 2lp+/ [t20(s1 )+t20( s2)]+/[t0 0(s3)-t 20(s3) ]) (0.1) where l,lp are the Kp-->pp and pp-->pp coupling constants, si are the center of mass energies of pion pairs and, tI ( I = 0, 2) is the S wave scattering amplitude for isospin I given by the Roy equation: tI(s)=s- 4m2p eid(s) sind( s) . Here d(s) is phase shift which depends on the scattering length, a. We deduce p+p0(p 0p0) scattering lengths to be a00 = 0.199 +/- 0.003(stat) +/- 0.002( syst) and a20 = -0.0285 +/- 0.0008 (stat)+0.0012 - 0.0007 (syst). This also is the first experimental determination of Weinberg's universal curve[5] W=2a20- 5a2 0=0.540+/-0.007(stat) +0.005-0.007(syst) .

Baker, Troy Andrew

2000-10-01

90

SAGE II aerosol correlative observations - Profile measurements  

NASA Technical Reports Server (NTRS)

Profiles of the aerosol extinction measurements from the Stratospheric Aerosol and Gas Experiment (SAGE) II are compared with profiles from five correlative experiments between November 1984 and July 1986. The correlative profiles were derived from six-channel dustsonde measurements and two-wavelength lidar backscatter data. The correlation between the dustsonde- and lidar-derived measurements and the SAGE II data is good, validating the SAGE II lower stratospheric aerosol extinction measurements.

Osborn, M. T.; Rosen, J. M.; Mccormick, M. P.; Wang, Pi-Huan; Livinfston, J. M.

1989-01-01

91

Energy-z correlation measurements of electron bunches  

NASA Astrophysics Data System (ADS)

Bunch length and energy-z correlation measurements were performed on the high energy (28.5 GeV) electron test beam of the A-line and End Station A (ESA) facilities at the SLAC National Accelerator Laboratory. The longitudinal profile of each bunch was measured by imaging the synchrotron light emitted as the electrons traversed a highly dispersive bend after being streaked by a transverse rf deflecting cavity. In addition, high frequency diodes and pyroelectric detectors placed at a ceramic gap in the beam line were used to measure the length of the bunch in ESA.

Molloy, Stephen; Emma, Paul; Frisch, Josef; Iverson, Rick; Ross, Marc; McCormick, Doug; Woods, Mike; Walston, Sean

2010-08-01

92

Leukocyte Telomere Length in Major Depression: Correlations with Chronicity, Inflammation and Oxidative Stress - Preliminary Findings  

PubMed Central

Background Depression is associated with an unusually high rate of aging-related illnesses and early mortality. One aspect of “accelerated aging” in depression may be shortened leukocyte telomeres. When telomeres critically shorten, as often occurs with repeated mitoses or in response to oxidation and inflammation, cells may die. Indeed, leukocyte telomere shortening predicts early mortality and medical illnesses in non-depressed populations. We sought to determine if leukocyte telomeres are shortened in Major Depressive Disorder (MDD), whether this is a function of lifetime depression exposure and whether this is related to putative mediators, oxidation and inflammation. Methodology Leukocyte telomere length was compared between 18 unmedicated MDD subjects and 17 controls and was correlated with lifetime depression chronicity and peripheral markers of oxidation (F2-isoprostane/Vitamin C ratio) and inflammation (IL-6). Analyses were controlled for age and sex. Principal Findings The depressed group, as a whole, did not differ from the controls in telomere length. However, telomere length was significantly inversely correlated with lifetime depression exposure, even after controlling for age (p<0.05). Average telomere length in the depressed subjects who were above the median of lifetime depression exposure (?9.2 years' cumulative duration) was 281 base pairs shorter than that in controls (p<0.05), corresponding to approximately seven years of “accelerated cell aging.” Telomere length was inversely correlated with oxidative stress in the depressed subjects (p<0.01) and in the controls (p<0.05) and with inflammation in the depressed subjects (p<0.05). Conclusions These preliminary data indicate that accelerated aging at the level of leukocyte telomeres is proportional to lifetime exposure to MDD. This might be related to cumulative exposure to oxidative stress and inflammation in MDD. This suggest that telomere shortening does not antedate depression and is not an intrinsic feature. Rather, telomere shortening may progress in proportion to lifetime depression exposure.

Wolkowitz, Owen M.; Mellon, Synthia H.; Epel, Elissa S.; Lin, Jue; Dhabhar, Firdaus S.; Su, Yali; Reus, Victor I.; Rosser, Rebecca; Burke, Heather M.; Kupferman, Eve; Compagnone, Mariana; Nelson, J. Craig; Blackburn, Elizabeth H.

2011-01-01

93

Aging phenotypes in cultured normal human mammary epithelial cells are correlated with decreased telomerase activity independent of telomere length  

PubMed Central

Background Shortening of telomeres, which are essential for maintenance of genomic integrity, is a mechanism commonly associated with the aging process. Here we ascertained whether changes in telomere lengths or telomerase activity correlated with age in normal human mammary epithelial cells (HMEC), or with phenotypes of aging in breast. Accordingly, flow cytometry fluorescence in situ hybridization (flowFISH) was used to determine relative telomere lengths (RTL), and telomerase activity was measured by the telomeric repeat amplification protocol (TRAP), in a collection of 41 primary HMEC strains established from women aged 16 to 91 years. Results RTL measurements of HMEC strains that were heterogeneous with respect to lineage composition revealed no significant associations between telomere length with age, maximum observed population doublings, or with lineage composition of the strains. However, within strains, luminal epithelial and cKit-expressing epithelial progenitor cells that were flow cytometry-enriched from individual HMEC strains exhibited significantly shorter telomeres relative to isogenic myoepithelial cells (P?correlate with RTL. Telomerase activity declined with age; the average age of strains that exhibited TRAP activity was 29.7?±?3.9y, whereas the average age of strains with no detectable TRAP activity was 49.0?±?4.9y (P?correlated with phenotypes of aging previously described in HMEC strains; increased proportions of CD227-expressing luminal epithelial cells (P?correlate with the chronological ages of HMEC strains, whereas decreased telomerase activity correlated with age and with lineage distribution phenotypes characteristic of aging.

2013-01-01

94

Audiogram, body mass, and basilar papilla length: correlations in birds and predictions for extinct archosaurs  

NASA Astrophysics Data System (ADS)

The inner ear in the group of archosaurs (birds, crocodilians, and extinct dinosaurs) shows a high degree of structural similarity, enabling predictions of their function in extinct species based on relationships among similar variables in living birds. Behavioral audiograms and morphological data on the length of the auditory sensory epithelium (the basilar papilla) are available for many avian species. By bringing different data sets together, we show that body mass and the size of the basilar papilla are significantly correlated, and the most sensitive frequency in a given species is inversely related to the body mass and the length of the basilar papilla. We also demonstrate that the frequency of best hearing is correlated with the high-frequency limit of hearing. Small species with a short basilar papilla hear higher frequencies compared with larger species with a longer basilar papilla. Based on the regression analysis of two significant correlations in living archosaurs (best audiogram frequency vs body mass and best audiogram frequency vs papillar length), we suggest that hearing in large dinosaurs was restricted to low frequencies with a high-frequency limit below 3 kHz.

Gleich, Otto; Dooling, Robert J.; Manley, Geoffrey A.

2005-12-01

95

Total diesel exhaust particulate length measurements using a modified household smoke alarm ionization chamber.  

PubMed

To evaluate the effectiveness of various means to combat the negative health effects of ultrafine particles emitted by internal combustion engines, a reliable, low-cost instrument for dynamic measurements of the exhaust emissions of ultrafine particulate matter (PM) is needed. In this study, an ordinary ionization-type building smoke detector was modified to serve as a measuring ionization chamber and utilized for dynamic measurements of PM emissions from diesel engines. When used with diluted exhaust, the readings show an excellent correlation with total particulate length. The instrument worked well with raw and diluted exhaust and with varying emission levels and is well suitable for on-board use. PMID:21387930

Vojtisek-Lom, Michal

2011-02-01

96

Leg length inequality measured by ultrasound and clinical methods.  

PubMed

Leg length inequality (LLI) was determined by ultrasound and two clinical methods in 100 subjects without previous disorders of the lower extremities. The mean LLI by ultrasound was 4.1 mm (range: 0-16 mm). An LLI of 10 mm or more was found in 4% of the subjects. The mean inter-observer variation by ultrasound was 0.9 mm (range: divided by 5-8 mm), which was significantly less than that obtained by clinical methods. The 95% confidence interval of inter-observer variation (+/- 2 SD) by ultrasound was +/- 5 mm and this interval is assumed to represent the accuracy of the method. Because LLI measurement by ultrasound is more reliable than clinical methods, ultrasound is recommended for routine use in clinical practice. PMID:1563425

Junk, S; Terjesen, T; Rossvoll, I; Bråten, M

1992-01-01

97

Representative Elementary Length to Measure Soil Mass Attenuation Coefficient  

PubMed Central

With increasing demand for better yield in agricultural areas, soil physical property representative measurements are more and more essential. Nuclear techniques such as computerized tomography (CT) and gamma-ray attenuation (GAT) have been widely employed with this purpose. The soil mass attenuation coefficient (?s) is an important parameter for CT and GAT analysis. When experimentally determined (?es), the use of suitable sized samples enable to evaluate it precisely, as well as to reduce measurement time and costs. This study investigated the representative elementary length (REL) of sandy and clayey soils for ?es measurements. Two radioactive sources were employed (241Am and 137Cs), three collimators (2–4?mm diameters), and 14 thickness (x) samples (2–15?cm). Results indicated ideal thickness intervals of 12–15 and 2–4?cm for the sources 137Cs and 241Am, respectively. The application of such results in representative elementary area (REA) evaluations in clayey soil clods via CT indicated that ?es average values obtained for x?>?4?cm and source 241Am might induce to the use of samples which are not large enough for soil bulk density evaluations (?s). As a consequence, ?s might be under- or overestimated, generating inaccurate conclusions about the physical quality of the soil under study.

Borges, J. A. R.; Pires, L. F.; Costa, J. C.

2014-01-01

98

Carotid-Femoral Pulse Wave Velocity: Impact of Different Arterial Path Length Measurements  

PubMed Central

Background Carotid-femoral pulse wave velocity (PWV) is the most established index of arterial stiffness. Yet there is no consensus on the methodology in regard to the arterial path length measurements conducted on the body surface. Currently, it is not known to what extent the differences in the arterial path length measurements affect absolute PWV values. Methods Two hundred fifty apparently healthy adults (127 men and 123 women, 19-79 years) were studied. Carotid-femoral PWV was calculated using (1) the straight distance between carotid and femoral sites (PWVcar–fem), (2) the straight distance between suprasternal notch and femoral site minus carotid arterial length (PWV(ssn–fem)-(ssn–car)), (3) the straight distance between carotid and femoral sites minus carotid arterial length (PWV(car–fem)-(ssn–car)), and (4) the combined distance from carotid site to the umbilicus and from the umbilicus to femoral site minus carotid arterial length (PWV(ssn–umb–fem)-(ssn–car)). Results All the calculated PWV were significantly correlated with each other (r=0.966-0.995). PWV accounting for carotid arterial length were 16-31% lower than PWVcar–fem. PWVcar–fem value of 12 m/sec corresponded to 8.3 m/sec for PWV(ssn–fem)-(ssn–car), 10.0 m/sec for PWV(car–fem)-(ssn–car), and 8.9 m/sec for PWV(ssn–umb–fem)-(ssn–car). Conclusion Different body surface measurements used to estimate arterial path length would produce substantial variations in absolute PWV values.

Sugawara, Jun; Hayashi, Koichiro; Yokoi, Takashi; Tanaka, Hirofumi

2009-01-01

99

Measurement of the Length of an Optical Trap  

NASA Technical Reports Server (NTRS)

NASA Glenn has been involved in developing optical trapping and optical micromanipulation techniques in order to develop a tool that can be used to probe, characterize, and assemble nano and microscale materials to create microscale sensors for harsh flight environments. In order to be able to assemble a sensor or probe candidate sensor material, it is useful to know how far an optical trap can reach; that is, the distance beyond/below the stable trapping point through which an object will be drawn into the optical trap. Typically, to measure the distance over which an optical trap would influence matter in a horizontal (perpendicular to beam propagation) direction, it was common to hold an object in one optical trap, place a second optical trap a known distance away, turn off the first optical trap, and note if the object was moved into the second trap when it was turned on. The disadvantage of this technique is that it only gives information of trap influence distance in horizontal (x y) directions. No information about the distance of the influence of the trap is gained in the direction of propagation of the beam (the z direction). A method was developed to use a time-of-flight technique to determine the length along the propagation direction of an optical trap beam over which an object may be drawn into the optical trap. Test objects (polystyrene microspheres) were held in an optical trap in a water-filled sample chamber and raised to a pre-determined position near the top of the sample chamber. Next, the test objects were released by blocking the optical trap beam. The test objects were allowed to fall through the water for predetermined periods of time, at the end of which the trapping beam was unblocked. It was noted whether or not the test object returned to the optical trap or continued to fall. This determination of the length of an optical trap's influence by this manner assumes that the test object falls through the water in the sample chamber at terminal velocity for the duration of its fall, so that the distance of trap influence can be computed simply by: d = VTt, where d is the trap length (or distance of trap reach), VT is the terminal velocity of the test object, and t is the time interval over which the object is allowed to fall.

Wrbanek, Susan Y.

2010-01-01

100

Energy-z correlation measurements of electron bunches  

Microsoft Academic Search

Bunch length and energy-z correlation measurements were performed on the high energy (28.5 GeV) electron test beam of the A-line and End Station A (ESA) facilities at the SLAC National Accelerator Laboratory. The longitudinal profile of each bunch was measured by imaging the synchrotron light emitted as the electrons traversed a highly dispersive bend after being streaked by a transverse

Stephen Molloy; Paul Emma; Josef Frisch; Rick Iverson; Marc Ross; Doug McCormick; Mike Woods; Sean Walston

2010-01-01

101

Cavity length measurement: bias from misalignment and mismatching.  

PubMed

SR-POEM, the sounding rocket principle of equivalence measurement, uses a set of six tracking-frequency laser gauges operating in Fabry-Perot cavities to determine the relative acceleration of two test masses (TMs) that are chemically different. One end of each cavity is a flat mirror on a TM; the other end is a concave coupling mirror mounted to a common reference plate. The tracking-frequency laser gauges work by locking a variable frequency laser to the cavity by the method of Pound, Drever, and Hall. Because the TMs are unconstrained, they are expected to rotate slightly during measurement. Although the distance measurements are intended to be based on the TEM?? cavity mode, any misalignment will couple into higher-order transverse modes, particularly the TEM?? and TEM??. Light thus coupled will contribute a spurious signal to the cavity locking servo that causes a bias (i.e., a systematic error) in the length determination. The spurious signal proportional to the misalignment has an antisymmetric distribution at the detector and thus has a zero average, but causes a distance bias because of the inhomogeneity of the detector responsivity. To prevent such bias, SR-POEM includes a servo to keep the incoming laser beam aligned with the cavity. The required performance of that alignment servo is less stringent than has already been achieved by other projects. There is also a spurious signal proportional to the square of the misalignment that produces a symmetric distribution at the detector. This signal is also made unimportant by the operation of an alignment servo, even when operating well above the shot noise limit. We also look at the locking of a laser to a high finesse cavity and conclude that the alignment quality sets a bound on the ratio of measurement accuracy to cavity linewidth. PMID:24513772

Reasenberg, Robert D

2013-11-20

102

Optimal chirped probe pulse length for terahertz pulse measurement.  

PubMed

A detailed analysis of the relationship between the duration of the chirped probe pulse and the bipolar terahertz (THz) pulse length in the spectral encoding technique is carried out. We prove that there is an optimal chirped probe pulse length (or an optimal chirp rate of the chirped probe pulse) matched to the input THz pulse length and derive a rigorous relationship between them. We find that only under this restricted condition the THz signal can be correctly retrieved. PMID:18679511

Peng, Xiao-Yu; Willi, Oswald; Chen, Min; Pukhov, Alexander

2008-08-01

103

Telomere length measurement by a novel monochrome multiplex quantitative PCR method  

PubMed Central

The current quantitative polymerase chain reaction (QPCR) assay of telomere length measures telomere (T) signals in experimental DNA samples in one set of reaction wells, and single copy gene (S) signals in separate wells, in comparison to a reference DNA, to yield relative T/S ratios that are proportional to average telomere length. Multiplexing this assay is desirable, because variation in the amount of DNA pipetted would no longer contribute to variation in T/S, since T and S would be collected within each reaction, from the same input DNA. Multiplexing also increases throughput and lowers costs, since half as many reactions are needed. Here, we present the first multiplexed QPCR method for telomere length measurement. Remarkably, a single fluorescent DNA-intercalating dye is sufficient in this system, because T signals can be collected in early cycles, before S signals rise above baseline, and S signals can be collected at a temperature that fully melts the telomere product, sending its signal to baseline. The correlation of T/S ratios with Terminal Restriction Fragment (TRF) lengths measured by Southern blot was stronger with this monochrome multiplex QPCR method (R2 = 0.844) than with our original singleplex method (R2 = 0.677). Multiplex T/S results from independent runs on different days were highly reproducible (R2 = 0.91).

Cawthon, Richard M.

2009-01-01

104

The transport of low-frequency turbulence in astrophysical flows: Correlation lengths  

NASA Astrophysics Data System (ADS)

Recently, Zank et al. 2012 developed a model to describe the transport of low-frequency turbulence in inhomogeneous and magnetized flows, based on the Elsässer description. By taking moments of the small scale Elsässer variables z+/-, transport equations for the total energy ET, the cross helicity EC, and the energy difference (residual energy) ED of the turbulence were derived. The set of transport equations was completed by introducing evolution equations for the correlation lengths ?+/- (corresponding to forward and backward propagating modes of the Elsässer variable), and the correlation length ?D (corresponding to the energy difference ED). A first simplification was achieved by setting ?+ = ?-. In this paper we show that, based on an integral scale for velocity correlations, the choice of ?+ = ?- has a certain phenomenology with some very specific implications on the set of transport equations. In particular, it is shown that ?D and z+/- can no longer be chosen arbitrarily, but must satisfy certain restrictions. These are discussed and a reduced transport model is derived.

Dosch, A.; Adhikari, L.; Zank, G. P.

2013-06-01

105

Water absorption length measurement with the ANTARES optical beacon system  

NASA Astrophysics Data System (ADS)

ANTARES is a neutrino telescope located in the Mediterranean Sea with the aim of detecting high energy neutrinos of extra-terrestrial origin. It consists of a three dimensional array on 12 detection lines of photomultiplier tubes (PMTs) able to detect the Cherenkov light induced by muons produced in the interaction of neutrinos with the surrounding water and seabed. To reach the best angular resolution, good time and positioning calibrations are required. The propagation of Cherenkov photons strongly depends on the optical properties of the sea water, which has an impact on the reconstruction efficiency. The determination of the optical parameters, as the absorption and scattering lengths, is crucial to calculate properly the effective area and the angular resolution of the detector. The ANTARES optical beacon system consists of pulsed and fast, well controlled light sources distributed throughout the detector to carry out in situ the relative time calibration of the detector components. In this contribution we show some results on the sea water optical properties and their stability measured with the optical beacon system.

Yepes-Ramirez, Harold; ANTARES Collaboration

2011-01-01

106

Critique: Length of Text and the Measurement of Cohesion.  

ERIC Educational Resources Information Center

Asserts that previous research in cohesion has mathematically adjusted the data in ways that assume a linear relation between text length and opportunities for writers to make cohesive ties; but, because cohesion is often redundant, that relation probably is not linear, giving an advantage to writers of longer essays. (MS)

Haswell, Richard H.

1988-01-01

107

Correlates of rehabilitation hospital length of stay among older African-American patients.  

PubMed Central

This study addresses a gap in the current literature on the correlates of rehabilitation hospital length of stay for older African Americans. Using data from 616 consecutively admitted rehabilitation patients who ranged in age from 50 to 103 years old, we tested the effect of patient's primary medical impairment; structural factors such as admit and discharge setting; level of depression (Geriatric Depression Scale); functional ability upon hospital admission (FIM score); and other control variables. Hierarchical linear regression models show that medical impairment alone was not a robust predictor of LOS. However, when controlling for structural and psychosocial factors, and medical condition, then circulation/amputation impairment was directly associated with longer LOS. Being unmarried or at risk for depression were also directly related to longer LOS. Consequently, rehabilitation administrators and hospital staff should note these findings to determine whether and how these factors affect discharge outcomes in their particular rehabilitative environments.

Mills, Terry L.; Lichtenberg, Peter A.; Wakeman, Melanie A.; Scott-Okafor, Hellena

2002-01-01

108

Relationships between otoacoustic emissions and a proxy measure of cochlear length derived from the auditory brainstem response  

PubMed Central

Brief tones of 1.0 and 8.0 kHz were used to evoke auditory brainstem responses (ABRs), and the differences between the wave-V latencies for those two frequencies were used as a proxy for cochlear length. The tone bursts (8 ms in duration including 2-ms rise/fall times, and 82 dB in level) were, or were not, accompanied by a continuous, moderately intense noise band, highpass filtered immediately above the tone. The proxy values for length were compared with various measures of otoacoustic emissions (OAEs) obtained from the same ears. All the correlations were low, suggesting that cochlear length, as measured by this proxy at least, is not strongly related to the various group and individual differences that exist in OAEs. Female latencies did not differ across the menstrual cycle, and the proxy length measure exhibited no sex difference (either for menses females vs. males or midluteal females vs. males) when the highpass noises were used. However, when the subjects were partitioned into Whites and Non-Whites, a substantial sex difference in cochlear length did emerge for the White group, although the correlations with OAEs remained low. Head size was not highly correlated with any of the ABR measures.

McFadden, Dennis; Garcia-Sierra, Adrian; Hsieh, Michelle D.; Maloney, Mindy M.; Champlin, Craig A.; Pasanen, Edward G.

2012-01-01

109

Correlation of interannual length-of-day variation with El Nino/Southern Oscillation, 1972-1986  

NASA Technical Reports Server (NTRS)

Correlation between interannual length-of-day (LOD) changes and an index representation of El Nino/Southern Oscillation (ENSO) for the period of 1972-1986 was examined in two ways: as the cross-correlation function in the time domain and as the complex coherence spectrum in the frequency domain. The ENSO representation was derived from barometric measurements from the Tahiti and Darwin, Australia, meteorological stations, as the difference of the sea-level pressure between the two locations. The cross correlation between this ENSO representation and LOD variation on the interannual time scale was found to have a maximum value of 0.68 and the LOD phase lag of 2 months, indicating that most of the interannual LOD variation is caused by ENSO, and that the transfer of ENSO's axial angular momentum to the solid earth lags behind the Tahiti-Darwin pressure variation by about 2 months. The corresponding coherence spectrum showed minimum correlation around biennial periods, indicating an influence of the stratospheric quasi-biennial oscillation on LOD variations.

Chao, B. Fong

1988-01-01

110

Titin isoform size is not correlated with thin filament length in rat skeletal muscle.  

PubMed

The mechanisms controlling thin filament length (TFL) in muscle remain controversial. It was recently reported that TFL was related to titin size, and that the latter might be involved in TFL determination. Titin plays several crucial roles in the sarcomere, but its function as it pertains to the thin filament has not been explored. We tested this relationship using several muscles from wild type rats and from a mutant rat model (Greaser et al., 2008) which results in increased titin size. Myofibrils were isolated from skeletal muscles [extensor digitorum longus (EDL), external oblique (EO), gastrocnemius (GAS), longissimus dorsi (LD), psoas major (PM), and tibialis anterior(TA)] using both adult wild type (WT) and homozygous mutant (HM) rats (n = 6 each). Phalloidin and antibodies against tropomodulin-4 (Tmod-4) and nebulin's N-terminus were used to determine TFL. The WT rats studied express skeletal muscle titin sizes ranging from 3.2 to 3.7 MDa, while the HM rats express a giant titin isoform sized at 3.8 MDa. No differences in phalloidin based TFL, nebulin distance, or Tmod distance were observed across genotypes. However, the HM rats demonstrated a significantly increased (p < 0.01) rest sarcomere length relative to the WT phenotype. It appears that the increased titin size, predominantly observed in HM rats' middle Ig domain, allows for increased extensibility. The data indicates that, although titin performs many sarcomeric functions, its correlation with TFL and structure could not be demonstrated in the rat. PMID:24550844

Greaser, Marion L; Pleitner, Jonathan M

2014-01-01

111

Single-shot electron bunch length measurements using a spatial electro-optical autocorrelation interferometer  

SciTech Connect

A spatial, electro-optical autocorrelation (EOA) interferometer using the vertically polarized lobes of coherent transition radiation (CTR) has been developed as a single-shot electron bunch length monitor at an optical beam port downstream the 100 MeV preinjector LINAC of the Swiss Light Source. This EOA monitor combines the advantages of step-scan interferometers (high temporal resolution) [D. Mihalcea et al., Phys. Rev. ST Accel. Beams 9, 082801 (2006) and T. Takahashi and K. Takami, Infrared Phys. Technol. 51, 363 (2008)] and terahertz-gating technologies [U. Schmidhammer et al., Appl. Phys. B: Lasers Opt. 94, 95 (2009) and B. Steffen et al., Phys. Rev. ST Accel. Beams 12, 032802 (2009)] (fast response), providing the possibility to tune the accelerator with an online bunch length diagnostics. While a proof of principle of the spatial interferometer was achieved by step-scan measurements with far-infrared detectors, the single-shot capability of the monitor has been demonstrated by electro-optical correlation of the spatial CTR interference pattern with fairly long (500 ps) neodymium-doped yttrium aluminum garnet (Nd:YAG) laser pulses in a ZnTe crystal. In single-shot operation, variations of the bunch length between 1.5 and 4 ps due to different phase settings of the LINAC bunching cavities have been measured with subpicosecond time resolution.

Suetterlin, Daniel [PUBLICA Swiss Federal Pension Fund, CH-3000 Berne (Switzerland); Paul Scherrer Institute, CH-5232 Villigen (Switzerland); Erni, Daniel [General and Theoretical Electrical Engineering (ATE), Faculty of Engineering, University of Duisburg-Essen, D-47048 Duisburg (Germany); Schlott, Volker [Department of Large Research Facilities, Paul Scherrer Institute, CH- 5232 Villigen (Switzerland); Sigg, Hans [Laboratory for Micro- and Nanotechnology, Paul Scherrer Institute, CH- 5232 Villigen (Switzerland); Jaeckel, Heinz [Department of Information Technology and Electrical Engineering, Electronics Laboratory, ETHZ, CH-8092 Zurich (Switzerland); Murk, Axel [Department of Microwave Physics, Institute of Applied Physics, University of Berne, CH-3012 Berne (Switzerland)

2010-10-15

112

Single-shot electron bunch length measurements using a spatial electro-optical autocorrelation interferometer.  

PubMed

A spatial, electro-optical autocorrelation (EOA) interferometer using the vertically polarized lobes of coherent transition radiation (CTR) has been developed as a single-shot electron bunch length monitor at an optical beam port downstream the 100 MeV preinjector LINAC of the Swiss Light Source. This EOA monitor combines the advantages of step-scan interferometers (high temporal resolution) [D. Mihalcea et al., Phys. Rev. ST Accel. Beams 9, 082801 (2006) and T. Takahashi and K. Takami, Infrared Phys. Technol. 51, 363 (2008)] and terahertz-gating technologies [U. Schmidhammer et al., Appl. Phys. B: Lasers Opt. 94, 95 (2009) and B. Steffen et al., Phys. Rev. ST Accel. Beams 12, 032802 (2009)] (fast response), providing the possibility to tune the accelerator with an online bunch length diagnostics. While a proof of principle of the spatial interferometer was achieved by step-scan measurements with far-infrared detectors, the single-shot capability of the monitor has been demonstrated by electro-optical correlation of the spatial CTR interference pattern with fairly long (500 ps) neodymium-doped yttrium aluminum garnet (Nd:YAG) laser pulses in a ZnTe crystal. In single-shot operation, variations of the bunch length between 1.5 and 4 ps due to different phase settings of the LINAC bunching cavities have been measured with subpicosecond time resolution. PMID:21034105

Sütterlin, Daniel; Erni, Daniel; Schlott, Volker; Sigg, Hans; Jäckel, Heinz; Murk, Axel

2010-10-01

113

Length Limitations of Far-End Crosstalk Measurements in Multipair Telephone Cables.  

National Technical Information Service (NTIS)

Far-End Crosstalk testing of production length cables is subject to possible measurement errors especially at the 6300 KHz test frequency of Bellcore TA series cable specifications. Cable attenuation at high frequencies and long lengths can reduce the sig...

J. M. Normile

1986-01-01

114

Correlate measurements at different test sites  

Microsoft Academic Search

A new method for systematic correlation of measurements in semi-anechoic and anechoic chambers is presented. A signal measured in a semi-anechoic chamber is first processed using the matrix-pencil method which is applied sequentially on small frequency intervals. On each interval the measured signal is decomposed into its propagating wave components. The component corresponding to the wave reflected from the ground

B. Fourestie; Z. Altman; J. Wiart; A. Azoulay

1999-01-01

115

Understanding the amplitudes of noise correlation measurements  

USGS Publications Warehouse

Cross correlation of ambient seismic noise is known to result in time series from which station-station travel-time measurements can be made. Part of the reason that these cross-correlation travel-time measurements are reliable is that there exists a theoretical framework that quantifies how these travel times depend on the features of the ambient noise. However, corresponding theoretical results do not currently exist to describe how the amplitudes of the cross correlation depend on such features. For example, currently it is not possible to take a given distribution of noise sources and calculate the cross correlation amplitudes one would expect from such a distribution. Here, we provide a ray-theoretical framework for calculating cross correlations. This framework differs from previous work in that it explicitly accounts for attenuation as well as the spatial distribution of sources and therefore can address the issue of quantifying amplitudes in noise correlation measurements. After introducing the general framework, we apply it to two specific problems. First, we show that we can quantify the amplitudes of coherency measurements, and find that the decay of coherency with station-station spacing depends crucially on the distribution of noise sources. We suggest that researchers interested in performing attenuation measurements from noise coherency should first determine how the dominant sources of noise are distributed. Second, we show that we can quantify the signal-to-noise ratio of noise correlations more precisely than previous work, and that these signal-to-noise ratios can be estimated for given situations prior to the deployment of seismometers. It is expected that there are applications of the theoretical framework beyond the two specific cases considered, but these applications await future work.

Tsai, Victor C.

2011-01-01

116

Generalized entropic measures of quantum correlations  

SciTech Connect

We propose a general measure of nonclassical correlations for bipartite systems based on generalized entropic functions and majorization properties. Defined as the minimum information loss due to a local measurement, in the case of pure states it reduces to the generalized entanglement entropy, i.e., the generalized entropy of the reduced state. However, in the case of mixed states it can be nonzero in separable states, vanishing just for states diagonal in a general product basis, like the quantum discord. Simple quadratic measures of quantum correlations arise as a particular case of the present formalism. The minimum information loss due to a joint local measurement is also discussed. The evaluation of these measures in simple relevant cases is as well provided, together with comparison with the corresponding entanglement monotones.

Rossignoli, R.; Canosa, N.; Ciliberti, L. [Departamento de Fisica-IFLP, Universidad Nacional de La Plata, C.C. 67, 1900 La Plata (Argentina)

2010-11-15

117

New Method for Automatic Body Length Measurement of the Collembolan, Folsomia candida Willem 1902 (Insecta: Collembola)  

PubMed Central

The collembolan, Folsomia candida, is widely used in soil ecotoxicology. In recent years, growth rate of collembolans has become as frequently used endpoint as reproduction rate in ecotoxicological studies. However, measuring collembolan body sizes to estimate growth rate is a complicated and time-consuming task. Here we present a new image analysis method, which facilitates and accelerates the body length measurement of the collembolan Folsomia candida. The new software package, called CollScope, consists of three elements: 1) an imaging device; 2) photographing software; 3) an ImageJ macro for image processing, measurement and data analysis. We give a complete description of the operation of the software, the image analyzing process and describe its accuracy and reliability. The software with a detailed usage manual is attached as Supplementary Material. We report a case study to demonstrate that the automated measurement of collembolan body sizes is highly correlated with the traditional manual measurements (estimated measuring accuracy 0.05 mm). Furthermore, we performed a dose-response ecotoxicity test using cadmium-sulfate by using CollScope as well as classical methods for size measurement. Size data measured by CollScope or manually did not differ significantly. Furthermore the new software package decreased time consumption of the measurements to 42% when tested on 35 animals. Consequently, methodological investigations performed in this study should be regarded as a recommendation for any other routine dose-response study where body growth is an endpoint.

Banszegi, Oxana; Kosztolanyi, Andras; Bakonyi, Gabor; Szabo, Borbala; Dombos, Miklos

2014-01-01

118

Length scale dependence and reliability of x-ray strain measurements in metallic glasses  

NASA Astrophysics Data System (ADS)

There is a long history of using x-ray scattering techniques for measuring elastic strain in crystalline materials. Only recently have these techniques been applied to metallic glasses. Results emerging from this work indicate that the elastic strain in metallic glasses varies with the distance from an average atom r in an asymptotic fashion. The reason for such anomalous length-scale behavior of elastic strain in these materials remains unclear. To investigate the origins of this behavior, high energy x-ray scattering experiments were carried out in this work on zirconium and palladium based metallic glass specimens subject to mechanical loading. In both these alloys, the elastic strain obtained from pair correlation function position shifts was found to approach the imposed strain asymptotically. This behavior was found to be independent of the uniaxial compression, uniaxial tension, or pure shear loading geometries. To further investigate the length-scale behavior, molecular dynamics simulations were carried out on a binary Lennard-Jones glass. Elastic strain in this model binary glass, when subject to uniaxial tensile deformation, qualitatively reproduced the length-scale behavior observed in the experiments when the strain was calculated from pair correlation function positions shifts. Other techniques for calculating strain, however, gave different results. Also, independent of the calculation methodology, imposing hydrostatic deformation resulted in nearly length-scale independent strain. These results seem to indicate that the presence of resolved shear stresses and non-affine displacements are central to the length-scale effect. Besides the anomalous length-scale behavior, recent data also suggest that the x-ray technique usually underestimates the elastic strain (with respect to macroscopic value), or overestimates the elastic modulus, in metallic glasses. To investigate this modulus discrepancy, a two-phase model, containing low density liquid-like regions and high density relaxed regions, was investigated. This model was found to be unsuitable because the density difference required to explain the observed discrepancy was too large to be physically meaningful. However, assuming presence of voids, as an extreme of the two phase model, was found to explain the observed discrepancy.

Vempati, Udaya K.

119

Tools for Thought: The Measurement of Length and Area.  

ERIC Educational Resources Information Center

The ability of children to solve measurement problems was studied in 2 experiments with 190 children aged 6 through 10 years in Oxford (England). Results suggest that in designing instruction both conceptual difficulties and difficulties that relate to particular measurement practice must be studied. The role of culturally transmitted measurement

Nunes, T.; And Others

1993-01-01

120

On the saturation of the refractive index structure function. II - Influence of the correlation length on astronomical 'seeing'  

NASA Technical Reports Server (NTRS)

A physical length scale in the wavefront corresponding to the parameter (r sub 0) characterizing the loss in detail in a long exposure image is identified, and the influence of the correlation scale of turbulence as r sub 0 approaches this scale is shown. Allowing for the effect of 2-point correlations in the fluctuations of the refractive index, Venkatakrishnan and Chatterjee (1987) proposed a modified law for the phase structure function. It is suggested that the departure of the phase structure function from the 5/3 power law for length scales in the wavefront approaching the correlation scale of turbulence may lead to better 'seeing' at longer wavelengths.

Venkatakrishnan, P.

1987-01-01

121

Quantum correlations and least disturbing local measurements  

SciTech Connect

We examine the evaluation of the minimum information loss due to an unread local measurement in mixed states of bipartite systems, for a general entropic form. Such a quantity provides a measure of quantum correlations, reducing for pure states to the generalized entanglement entropy, while in the case of mixed states it vanishes just for classically correlated states with respect to the measured system, as the quantum discord. General stationary conditions are provided, together with their explicit form for general two-qubit states. Closed expressions for the minimum information loss as measured by quadratic and cubic entropies are also derived for general states of two-qubit systems. As an application, we analyze the case of states with maximally mixed marginals, where a general evaluation is provided, as well as X states and the mixture of two aligned states.

Rossignoli, R.; Canosa, N.; Ciliberti, L. [Departamento de Fisica-IFLP, Universidad Nacional de La Plata, C.C. 67, La Plata (1900) (Argentina)

2011-11-15

122

Quantum Correlations and the Measurement Problem  

NASA Astrophysics Data System (ADS)

The transition from classical to quantum mechanics rests on the recognition that the structure of information is not what we thought it was: there are operational, i.e., phenomenal, probabilistic correlations that lie outside the polytope of local correlations. Such correlations cannot be simulated with classical resources, which generate classical correlations represented by the points in a simplex, where the vertices of the simplex represent joint deterministic states that are the common causes of the correlations. The `no go' hidden variable theorems tell us that we can't shoe-horn phenomenal correlations outside the local polytope into a classical simplex by supposing that something has been left out of the story. The replacement of the classical simplex by the quantum convex set as the structure representing probabilistic correlations is the analogue for quantum mechanics of the replacement of Newton's Euclidean space and time by Minkowski spacetime in special relativity. The nonclassical features of quantum mechanics, including the irreducible information loss on measurement, are generic features of correlations that lie outside the classical simplex. This paper is an elaboration of these ideas, which have their source in work by Pitowsky (J. Math. Phys. 27:1556, 1986; Math. Program. 50:395, 1991; Phys. Rev. A 77:062109, 2008), Garg and Mermin (Found. Phys. 14:1-39, 1984), Barrett (Phys. Rev. A 75:032304, 2007; Phys. Rev. A 7:022101, 2005) and others, e.g., Brunner et al. (arXiv:1303.2849, 2013), but the literature goes back to Boole (An Investigation of the Laws of Thought, Dover, New York, 1951). The final section looks at the measurement problem of quantum mechanics in this context. A large part of the problem is removed by seeing that the inconsistency in reconciling the entangled state at the end of a quantum measurement process with the definiteness of the macroscopic pointer reading and the definiteness of the correlated value of the measured micro-observable depends on a stipulation that is not required by the structure of the quantum possibility space. Replacing this stipulation by an alternative consistent stipulation is the first step to resolving the problem.

Bub, Jeffrey

2013-06-01

123

Measures and models for angular correlation and angular-linear correlation. [correlation of random variables  

NASA Technical Reports Server (NTRS)

Population models for dependence between two angular measurements and for dependence between an angular and a linear observation are proposed. The method of canonical correlations first leads to new population and sample measures of dependence in this latter situation. An example relating wind direction to the level of a pollutant is given. Next, applied to pairs of angular measurements, the method yields previously proposed sample measures in some special cases and a new sample measure in general.

Johnson, R. A.; Wehrly, T.

1976-01-01

124

Optical testing by absolute length measurement with wavelength tuning interferometer  

NASA Astrophysics Data System (ADS)

The surface shape and the absolute optical thickness of a fused-silica glass parallel plate were measured by wavelength tuning interferometry. An excess fractions method combined with the Fourier based frequency analysis removed a systematic error. The interference orders of the optical thickness fringes were finally estimated, which resulted in an accuracy of a few nanometers for the optical thickness measurement.

Hibino, Kenichi; Kim, Yangjin; Ito, Makoto

2013-05-01

125

CTR Bunch Length Measurement of Monoenergetic and Maxwellian Electron Beams from Laser Plasma Cathode  

Microsoft Academic Search

Recently, several plasma cathodes at universities and institutes can generate a monoenergetic electron beam. LBL measured the bunch length by the CTR (Coherent Transition Radiation) interferometer to determine it as about 50 fs (FWHM). We are trying to carry out a single-shot measurement of the bunch length by a infrared polychromator. As the first step forward it, we measured the

Mitsuru Uesaka; Akira Maekawa; Takeru Ohkubo; Ryosuke Tsujii; Kennichi Kinoshita; Yamazaki Atsushi; Kazuyuki Kobayashi; Yukio Shibata; Yasuhiro Kondo; Tomonao Hosokai; Alexei Zhidkov; Toshiharu Takahashi

2006-01-01

126

Measuring magnetic correlations in nanoparticle assemblies  

NASA Astrophysics Data System (ADS)

We illustrate how to extract correlations between magnetic moments in assemblies of nanoparticles from, e.g., electron holography data providing the combined knowledge of particle size distribution, inter-particle distances, and magnitude and orientation of each magnetic moment within a nanoparticle superstructure, We show, based on simulated data, how to build a radial/angular pair distribution function f(r,?) encoding the spatial and angular difference between every pair of magnetic moments. A scatter-plot of f(r,?) reveals the degree of structural and magnetic order present, and hence provides a measure of the strength and range of magnetic correlations.

Beleggia, M.; Frandsen, C.

2014-06-01

127

Quantum correlations in dual quantum measurements  

NASA Astrophysics Data System (ADS)

. We analyze the quantum measurement properties of dual non-degenerate parametric amplifers in the twin-beam configuration, in the cascaded back-action-evasion configuration, and in Kerr-type photon-number quantum non-demolition measurements. It is found that Einstein-Podolsky-Rosen correlations can be obtained between the quadrature components of an idler mode and the sum of the readout of two signal modes. Furthermore, we discuss dual-mode quantum non-demolition measurements on the combination of two light modes, and the generation of number-state entanglement.

Karlsson, Anders; Björk, Gunnar

1996-01-01

128

On the correlation between bond-length change and vibrational frequency shift in halogen-bonded complexes  

NASA Astrophysics Data System (ADS)

The C-Hal (Hal = Cl, Br, or I) bond-length change and the corresponding vibrational frequency shift of the C-Hal stretch upon the C-Hal ...Y (Y is the electron donor) halogen bond formation have been determined by using density functional theory computations. Plots of the C-Hal bond-length change versus the corresponding vibrational frequency shift of the C-Hal stretch all give straight lines. The coefficients of determination range from 0.94366 to 0.99219, showing that the correlation between the C-Hal bond-length change and the corresponding frequency shift is very good in the halogen-bonded complexes. The possible effects of vibrational coupling, computational method, and anharmonicity on the bond-length change-frequency shift correlation are discussed in detail.

Wang, Weizhou; Zhang, Yu; Ji, Baoming; Tian, Anmin

2011-06-01

129

On the correlation between bond-length change and vibrational frequency shift in halogen-bonded complexes.  

PubMed

The C-Hal (Hal = Cl, Br, or I) bond-length change and the corresponding vibrational frequency shift of the C-Hal stretch upon the C-Hal···Y (Y is the electron donor) halogen bond formation have been determined by using density functional theory computations. Plots of the C-Hal bond-length change versus the corresponding vibrational frequency shift of the C-Hal stretch all give straight lines. The coefficients of determination range from 0.94366 to 0.99219, showing that the correlation between the C-Hal bond-length change and the corresponding frequency shift is very good in the halogen-bonded complexes. The possible effects of vibrational coupling, computational method, and anharmonicity on the bond-length change-frequency shift correlation are discussed in detail. PMID:21682510

Wang, Weizhou; Zhang, Yu; Ji, Baoming; Tian, Anmin

2011-06-14

130

Comparison of length measurements provided by a femtosecond optical frequency comb.  

PubMed

This paper presents a comparison of length measurements between the wavelength and the adjacent pulse repetition interval length (APRIL) provided by a femtosecond optical frequency comb. A theoretical estimation of the frequency stability for stabilizing the wavelength and APRIL, the frequency parameters that affect the stability of the APRIL in air, and the ambiguity in the length measurement by the APRIL are investigated. We find that the APRIL can be used as a low-cost measurement for the absolute length over a range of hundreds of meters in laboratory conditions. PMID:24664052

Wei, Dong; Aketagawa, Masato

2014-03-24

131

FIBER LENGTH DISTRIBUTION MEASUREMENT FOR LONG GLASS AND CARBON FIBER REINFORCED INJECTION MOLDED THERMOPLASTICS  

SciTech Connect

Procedures for fiber length distribution (FLD) measurement of long fiber reinforced injection molded thermoplastics were refined for glass and carbon fibers. Techniques for sample selection, fiber separation, digitization and length measurement for both fiber types are described in detail. Quantitative FLD results are provided for glass and carbon reinforced polypropylene samples molded with a nominal original fiber length of 12.7 mm (1/2 in.) using equipment optimized for molding short fiber reinforced thermoplastics.

Kunc, Vlastimil [ORNL; Frame, Barbara J [ORNL; Nguyen, Ba N. [Pacific Northwest National Laboratory (PNNL); TuckerIII, Charles L. [University of Illinois, Urbana-Champaign; Velez-Garcia, Gregorio [Virginia Polytechnic Institute and State University

2007-01-01

132

Non invasive and surgical measurement of length of soft tissue from the tip of interdental papilla to the alveolar crest  

PubMed Central

Background Various methods, including clinical and radiographic techniques, can be used to assess periodontal regeneration in interproximal areas. The goal of the present study was to compare the papilla length relative to the alveolar bone crest measured by clinical, intrasurgical, and radiographic techniques. Materials and methods The study sample included 250 interproximal papillae in 68 patients with generalized chronic periodontitis. The papilla length from the alveolar bone crest was measured clinically (as the actual papilla length, APL), intrasurgically (as the bone probing length, BPL), and radiographically (as the radiographic bone length, RBL). Measurements were standardized by using acrylic resin stents, XCP rinn, a paralleling technique, and/or a radiographic grid. Results The mean (± standard deviation) for RBL was 4.9 ± 0.8 mm, BPL was 5.1 ± 0.6 mm, and APL was 5.1 ± 0.6 mm. Correlations between RBL and APL and between BPL and APL were 0.918 and 0.943, respectively (both P < 0.01). Conclusions If the clinical recordings are appropriately standardized, then noninvasive radiographic methods can be used to evaluate the papilla length with good accuracy.

Kolte, Rajashri A.; Kolte, Abhay P.; Ghodpage, Pallavi S.

2013-01-01

133

Microsatellite length variation in candidate genes correlates with habitat in the gilthead sea bream Sparus aurata.  

PubMed

The genetic basis and evolutionary implications of local adaptation in high gene flow marine organisms are still poorly understood. In several Mediterranean fish species, alternative migration patterns exist between individuals entering coastal lagoons that offer favourable conditions for growth and those staying in the sea where environmental conditions are less subject to rapid and stressful change. Whether these coexisting strategies are phenotypically plastic or include a role for local adaptation through differential survival needs to be determined. Here, we explore the genetic basis of alternate habitat use in western Mediterranean populations of the gilthead sea bream (Sparus aurata). Samples from lagoonal and open-sea habitats were typed for three candidate gene microsatellite loci, seven anonymous microsatellites and 44 amplified fragment length polymorphism markers to test for genotype-environment associations. While anonymous markers globally indicated high levels of gene flow across geographic locations and habitats, non-neutral differentiation patterns correlated with habitat type were found at two candidate microsatellite loci located in the promoter region of the growth hormone and prolactin genes. Further analysis of these two genes revealed that a mechanism based on habitat choice alone could not explain the distribution of genotype frequencies at a regional scale, thus implying a role for differential survival between habitats. We also found an association between allele size and habitat type, which, in the light of previous studies, suggests that polymorphisms in the proximal promoter region could influence gene expression by modulating transcription factor binding, thus providing a potential explanatory link between genotype and growth phenotype in nature. PMID:23061421

Chaoui, Lamya; Gagnaire, Pierre-Alexandre; Guinand, Bruno; Quignard, Jean-Pierre; Tsigenopoulos, Costas; Kara, M Hichem; Bonhomme, François

2012-11-01

134

Investigation on series of length of coding and non-coding DNA sequences of bacteria using multifractal detrended cross-correlation analysis.  

PubMed

In the framework of multifractal detrended cross-correlation analysis, we investigate characteristics of series of length of coding and non-coding DNA sequences of some bacteria and archaea. We propose the use of a multifractal cross-correlation series that can be defined for any pair of equal lengths data sequences (or time series) and that can be characterized by the full set of parameters that are attributed to any time series. Comparison between characteristics of series of length of coding and non-coding DNA sequences and of their associated multifractal cross-correlation series for selected groups is used for the identification of class affiliation of certain bacteria and archaea. The analysis is carried out using the dependence of the generalized Hurst exponent on the size of fluctuations, the shape of the singularity spectra, the shape and relative disposition of the curves of the singular measures scaling exponent and the values of the associated parameters. Empirically, we demonstrate that the series of lengths of coding and non-coding sequences as well as the associated multifractal cross-correlation series can be approximated as universal multifractals. PMID:23313335

Stan, Cristina; Cristescu, Monica Teodora; Luiza, Buimaga Iarinca; Cristescu, C P

2013-03-21

135

A tool for measuring the bending length in thin wires.  

PubMed

Great effort is currently being put into the development and construction of the second generation, advanced gravitational wave detectors, Advanced Virgo and Advanced LIGO. The development of new low thermal noise suspensions of mirrors, based on the experience gained in the previous experiments, is part of this task. Quasi-monolithic suspensions with fused silica wires avoid the problem of rubbing friction introduced by steel cradle arrangements by directly welding the wires to silica blocks bonded to the mirror. Moreover, the mechanical loss level introduced by silica (?fs ? 10(-7) in thin fused silica wires) is by far less than the one associated with steel. The low frequency dynamical behaviour of the suspension can be computed and optimized, provided that the wire bending shape under pendulum motion is known. Due to the production process, fused silica wires are thicker near the two ends (necks), so that analytical bending computations are very complicated. We developed a tool to directly measure the low frequency bending parameters of fused silica wires, and we tested it on the wires produced for the Virgo+ monolithic suspensions. The working principle and a set of test measurements are presented and explained. PMID:23556827

Lorenzini, M; Cagnoli, G; Cesarini, E; Losurdo, G; Martelli, F; Piergiovanni, F; Vetrano, F; Viceré, A

2013-03-01

136

A tool for measuring the bending length in thin wires  

NASA Astrophysics Data System (ADS)

Great effort is currently being put into the development and construction of the second generation, advanced gravitational wave detectors, Advanced Virgo and Advanced LIGO. The development of new low thermal noise suspensions of mirrors, based on the experience gained in the previous experiments, is part of this task. Quasi-monolithic suspensions with fused silica wires avoid the problem of rubbing friction introduced by steel cradle arrangements by directly welding the wires to silica blocks bonded to the mirror. Moreover, the mechanical loss level introduced by silica (?fs ~ 10-7 in thin fused silica wires) is by far less than the one associated with steel. The low frequency dynamical behaviour of the suspension can be computed and optimized, provided that the wire bending shape under pendulum motion is known. Due to the production process, fused silica wires are thicker near the two ends (necks), so that analytical bending computations are very complicated. We developed a tool to directly measure the low frequency bending parameters of fused silica wires, and we tested it on the wires produced for the Virgo+ monolithic suspensions. The working principle and a set of test measurements are presented and explained.

Lorenzini, M.; Cagnoli, G.; Cesarini, E.; Losurdo, G.; Martelli, F.; Piergiovanni, F.; Vetrano, F.; Viceré, A.

2013-03-01

137

Measurement of silicon dioxide surface phonon-polariton propagation length by attenuated total reflection  

NASA Astrophysics Data System (ADS)

The authors present an experimental measurement of the propagation length of surface phonon-polaritons on amorphous silicon dioxide using the method of attenuated total reflection. The measurements yield a propagation length of 10.8+/-1.3 ?m for the silicon dioxide surface phonon-polariton resonance at 9 ?m, which is in good agreement with the calculated value.

Chen, Dye-Zone A.; Chen, Gang

2007-09-01

138

Digital examination and transperineal ultrasonographic measurement of cervical length to assess risk of preterm delivery  

Microsoft Academic Search

Objective: To compare the diagnostic performance of cervical length measurement determined with transperineal ultrasonography and digital assessment of the cervix for the prediction of preterm delivery in patients with preterm labor. Method: 90 patients admitted to the hospital with the diagnosis of preterm labor and intact membrane underwent cervical length measurement by transperineal ultrasonography along with digital examination for cervical

L. S Öndero?lu

1997-01-01

139

Young Children's Understandings of Length Measurement: Evaluating a Learning Trajectory  

ERIC Educational Resources Information Center

This study investigated the development of length measurement ideas in students from prekindergarten through 2nd grade. The main purpose was to evaluate and elaborate the developmental progression, or levels of thinking, of a hypothesized learning trajectory for length measurement to ensure that the sequence of levels of thinking is consistent…

Szilagyi, Janka; Clements, Douglas H.; Sarama, Julie

2013-01-01

140

Study of the Correlation Between Dislocations and Diffusion Length in In(49)Ga(51)P Solar Cells.  

National Technical Information Service (NTIS)

A quantitative, contact-free method for extracting minority carrier diffusion length is used to measure the relatively small variations in diffusion length associated with dislocation bands in mismatched epitaxy in the p-type region of a two dimensional h...

S. E. Williams

2008-01-01

141

Modeling the Length Effect: Specifying the Relation with Visual and Phonological Correlates of Reading  

ERIC Educational Resources Information Center

Beginning readers' reading latencies increase as words become longer. This length effect is believed to be a marker of a serial reading process. We examined the effects of visual and phonological skills on the length effect. Participants were 184 second-grade children who read 3- to 5-letter words and nonwords. Results indicated that reading…

van den Boer, Madelon; de Jong, Peter F.; Haentjens-van Meeteren, Marleen M.

2013-01-01

142

Correlation-based phase noise measurements  

NASA Astrophysics Data System (ADS)

In the characterization of the phase noise of a component, it is common practice to measure the cross-spectrum density at the output of two phase detectors that simultaneously compare the component output signal to a common reference. This technique, which is based on correlation and averaging, allows the rejection of the phase detector noise. On the other hand, it is known that the interferometer exhibits lower noise floor and higher conversion gain than other phase detectors suitable to radio-frequency and microwave bands. Thus, we experimented on an improved instrument in which the phase noise of a component is measured by correlating and averaging the output of two interferometers. The measurement sensitivity, given in terms of noise floor, turns out to be limited by the temperature uniformity of the instrument, instead of the absolute temperature T. This feature makes the instrument suitable to investigate the spectrum S?(f) of phase fluctuations below kBT/Po, i.e., the thermal energy kBT referred to the carrier power Po. The described method is suitable to the implementation of instruments in a wide frequency range, from some 100 kHz to 40 GHz and beyond. In principle, this method can also be exploited for the measurement of amplitude noise. Theory and experimental proof are given.

Rubiola, Enrico; Giordano, Vincent

2000-08-01

143

Eddy correlation measurements of submarine groundwater discharge  

USGS Publications Warehouse

This paper presents a new, non-invasive means of quantifying groundwater discharge into marine waters using an eddy correlation approach. The method takes advantage of the fact that, in virtually all aquatic environments, the dominant mode of vertical transport near the sediment-water interface is turbulent mixing. The technique thus relies on measuring simultaneously the fluctuating vertical velocity using an acoustic Doppler velocimeter and the fluctuating salinity and/or temperature using rapid-response conductivity and/or temperature sensors. The measurements are typically done at a height of 5-15??cm above the sediment surface, at a frequency of 16 to 64??Hz, and for a period of 15 to 60??min. If the groundwater salinity and/or temperature differ from that of the water column, the groundwater specific discharge (cm d- 1) can be quantified from either a heat or salt balance. Groundwater discharge was estimated with this new approach in Salt Pond, a small estuary on Cape Cod (MA, USA). Estimates agreed well with previous estimates of discharge measured using seepage meters and 222Rn as a tracer. The eddy correlation technique has several desirable characteristics: 1) discharge is quantified under in-situ hydrodynamic conditions; 2) salinity and temperature can serve as two semi-independent tracers of discharge; 3) discharge can be quantified at high temporal resolution, and 4) long-term records of discharge may be possible, due to the low power requirements of the instrumentation. ?? 2007 Elsevier B.V. All rights reserved.

Crusius, J.; Berg, P.; Koopmans, D. J.; Erban, L.

2008-01-01

144

A Preliminary Test of Measurement of Joint Angles and Stride Length with Wireless Inertial Sensors for Wearable Gait Evaluation System  

PubMed Central

The purpose of this study is to develop wearable sensor system for gait evaluation using gyroscopes and accelerometers for application to rehabilitation, healthcare and so on. In this paper, simultaneous measurement of joint angles of lower limbs and stride length was tested with a prototype of wearable sensor system. The system measured the joint angles using the Kalman filter. Signals from the sensor attached on the foot were used in the stride length estimation detecting foot movement automatically. Joint angles of the lower limbs were measured with stable and reasonable accuracy compared to those values measured with optical motion measurement system with healthy subjects. It was expected that the stride length measurement with the wearable sensor system would be practical by realizing more stable measurement accuracy. Sensor attachment position was suggested not to affect significantly measurement of slow and normal speed movements in a test with the rigid body model. Joint angle patterns measured in 10?m walking with a healthy subject were similar to common patterns. High correlation between joint angles at some characteristic points and stride velocity were also found adequately. These results suggested that the wireless wearable inertial sensor system could detect characteristics of gait.

Watanabe, Takashi; Saito, Hiroki; Koike, Eri; Nitta, Kazuki

2011-01-01

145

Probing Macroscopic Realism via Ramsey Correlation Measurements.  

PubMed

We describe a new and experimentally feasible protocol for performing fundamental tests of quantum mechanics with massive objects. In our approach, a single two-level system is used to probe the motion of a nanomechanical resonator via multiple Ramsey interference measurements. This scheme enables the measurement of modular variables of macroscopic continuous-variable systems; we show that correlations thereof violate a Leggett-Garg inequality and can be applied for tests of quantum contextuality. Our method can be implemented with a variety of different solid-state or photonic qubit-resonator systems, and it provides a clear experimental signature to distinguish the predictions of quantum mechanics from those of other alternative theories at a macroscopic scale. PMID:24877918

Asadian, A; Brukner, C; Rabl, P

2014-05-16

146

Correction of the measurement of fiber length of short fiber reinforced thermoplastics  

Microsoft Academic Search

Short fiber reinforced thermoplastics are often made using extrusion compounding and injection moulding techniques. Fiber breakage takes place during processing. In finished fiber reinforced parts, there often exists a fiber length distribution. Measurement of fiber length is often performed on photographs of short fibers obtained from burning off or dissolving the matrix. However, relatively long fibers crossing the photographs cannot

Shao-Yun Fu; Yiu-Wing Mai; Emma Chui-Yee Ching; Robert K. Y Li

2002-01-01

147

Experimental study of the correlation length of critical-current fluctuations in the presence of surface disorder: Probing vortex long-range interactions  

NASA Astrophysics Data System (ADS)

We report on critical currents and voltage noise measurements in niobium strips in the superconducting state, in the presence of a bulk vortex lattice (Bcorrelation length of the current fluctuations can be associated with the electromagnetic skin depth of vortex superficial instabilities. The modification of the surface state by means of low energy irradiation induces a strong modification of the critical current and of the noise. The appearance of a corner frequency in the spectral domain can be linked with the low wave vectors of the artificial corrugation. Since this latter occurs only for Bcorrelation length to extend up to values imposed by the surface topography.

Scola, J.; Pautrat, A.; Goupil, C.; Simon, Ch.

2006-01-01

148

A transient assay in plant cells reveals a positive correlation between extrachromosomal recombination rates and length of homologous overlap.  

PubMed Central

An assay to monitor homologous recombination in plant cells has been established by cotransfecting Nicotiana plumbaginifolia protoplasts with different topological forms of plasmids of various deletion mutants of a non-selectable marker gene, the beta-glucuronidase (GUS) gene. Transient GUS enzyme activities were measured by a sensitive assay. In the nuclear DNA of the cotransfected protoplasts the recombined complete GUS gene could be detected by a specially modified PCR analysis. In comparison to the standard assay, which monitors homologous recombination by integration of a selectable marker, the described assay avoids position effects of gene expression, is fast, easy to handle and large numbers of samples can be processed simultaneously. We were able to demonstrate a positive correlation between the length of overlapping homology (up to 1200 base pairs) of the transfected supercoiled circular or linearized plasmids and the respective GUS activities. We found a significant drop in the recombination rates when the overlap of both substrates was reduced to 456 basepairs or less. The requirement for such a long stretch of homology for efficient recombination might ensure the stability of the rather repetitive plant genome. Images

Puchta, H; Hohn, B

1991-01-01

149

Exploring the spatial heterogeneity of terraced landscapes using LiDAR: the Slope Local Length of Auto-Correlation (SLLAC).  

NASA Astrophysics Data System (ADS)

Terraces represent an outstanding example that displays centuries of a ubiquitous human-Earth interaction, in a very specific and productive way, and they are a significant part of numerous local economies. They, in fact, optimise the local resources for agricultural purposes, but also exploit marginal landscapes, expanding local populations. The ubiquity, variety, and importance of terraces have motivated studies designed to understand them better both as cultural and ecological features, but also as elements that can deeply influence runoff generation and propagation, contributing to local instabilities, and triggering or aggravating land degradation processes. Their vulnerability in the face of fast-growing urban settlements and the changes in agricultural practices is also well known, prompting protection measures strongly supported by local communities, but also by national and international projects. This work explores the spatial heterogeneity of terraced landscapes, identifying a proper indicator able to discriminate a terraced landscape respect to a more natural one. Recognizing and characterizing terraced areas can offer important multi-temporal insights into issues such as agricultural sustainability, indigenous knowledge systems, human-induced impact on soil degradation or erosive and landslide processes, geomorphological and pedologic processes that influence soil development, and climatic and biodiversity changes. More in detail, the present work introduces a new morphological indicator from LiDAR, effectively implementable for the automatic characterization of terraced landscapes. For the study, we tested the algorithm for environments that differ in term of natural morphology and terracing system. Starting from a LiDAR Digital Terrain Models (DTM), we considered the local auto-correlation (~local self-similarity) of the slope, calculating the correlation between a slope patch and its surrounding areas. We define the resulting map as the "Slope Local Length of Auto-Correlation", or SLLAC map. The SLLAC map texture is characterized by the presence of peculiar elongated fibers that change depending on the landscape morphology, and on the type of terracing system. The differences in texture can be measured, and they can be used to discriminate terraced areas from more natural ones. Given the raising importance of these landscapes, the proposed procedure can offer an important and promising tool to explore the spatial heterogeneity of terraced sites.

Sofia, Giulia; Marinello, Francesco; Tarolli, Paolo

2014-05-01

150

A Robust Correlation Measure for Correspondence Estimation  

Microsoft Academic Search

A median correlation for the estimation of corresponding points in stereovision is proposed. It is based on the normalised correlation coefficient using the median instead of the mean. Its performance appears to be superior than conventional correlation specially in depth discontinuities image areas. This conclusion is derived from an empirical evaluation in which the proposed correlation is compared with the

Maria F. Trujillo; Ebroul Izquierdo

2004-01-01

151

The Importance of Parameter Variances, Correlations Lengths, and Cross-Correlations in Reactive Transport Models: Key Considerations for Assessing the Need for Microscale Information (Invited)  

NASA Astrophysics Data System (ADS)

A process-oriented modeling approach is implemented to examine the importance of parameter variances, correlation lengths, and especially cross-correlations in contaminant transport predictions over large scales. It is shown that the most important consideration is the correlation between flow rates and retardation processes (e.g., sorption, matrix diffusion) in the system. If flow rates are negatively correlated with retardation factors in systems containing multiple flow pathways, then characterizing these negative correlation(s) may have more impact on reactive transport modeling than microscale information. Such negative correlations are expected in porous-media systems where permeability is negatively correlated with clay content and rock alteration (which are usually associated with increased sorption). Likewise, negative correlations are expected in fractured rocks where permeability is positively correlated with fracture apertures, which in turn are negatively correlated with sorption and matrix diffusion. Parameter variances and correlation lengths are also shown to have important effects on reactive transport predictions, but they are less important than parameter cross-correlations. Microscale information pertaining to contaminant transport has become more readily available as characterization methods and spectroscopic instrumentation have achieved lower detection limits, greater resolution, and better precision. Obtaining detailed mechanistic insights into contaminant-rock-water interactions is becoming a routine practice in characterizing reactive transport processes in groundwater systems (almost necessary for high-profile publications). Unfortunately, a quantitative link between microscale information and flow and transport parameter distributions or cross-correlations has not yet been established. One reason for this is that quantitative microscale information is difficult to obtain in complex, heterogeneous systems, so simple systems that lack the complexity and heterogeneity of real aquifer materials are often studied. Another is that instrumentation used to obtain microscale information often probes only one variable or family of variables at a time, so linkages to other variables must be inferred by indirect means from other lines of evidence. Despite these limitations, microscale information can be useful in the development and validation of reactive transport models. For example, knowledge of mineral phases that have strong affinities for contaminants can help in the development of cross-correlations between flow and sorption parameters via characterization of permeability and mineral distributions in aquifers. Likewise, microscale information on pore structures in low-permeability zones and contaminant penetration distances into these zones from higher-permeability zones (e.g., fractures) can provide valuable constraints on the representation of diffusive mass transfer processes between flowing porosity and secondary porosity. The prioritization of obtaining microscale information in any groundwater system can be informed by modeling exercises such as those conducted for this study.

Reimus, P. W.

2010-12-01

152

Cesium oscillator strengths measured with a multiple-path-length absorption cell  

NASA Technical Reports Server (NTRS)

Absorption-oscillator-strength measurements for the principal series in cesium were measured using a multiple-path-length cell. The optical arrangement included a movable transverse path for checking the uniformity of the alkali density along the length of the cell and which also allowed strength measurements to be made simultaneously on both strong and weak lines. The strengths measured on the first 10 doublets indicate an increasing trend in the doublet ratio. The individual line strengths are in close agreement with the high resolution measurements of Pichler (1974) and with the calculations of Norcross (1973).

Exton, R. J.

1976-01-01

153

Neurofilament content is correlated with branch length in developing collateral branches of Xenopus spinal cord neurons.  

PubMed

During development, axons form interstitial collateral branches, which are initially dynamic but gradually stabilize as the projection sharpens. The initial outgrowth of collaterals is characterized by transitions in growth dynamics that occur at different lengths. Below 10 microm, collateral branches start out as unstable, thin filopodia. Above 30 microm, the branches stabilize. Although the relationship between branch length and the presence of microfilaments and microtubules has been well characterized, relatively less is known about the development of the neurofilament cytoskeleton in collateral branches. In the main axon, successive stages of outgrowth are accompanied by changes in the polypeptide composition of neurofilaments (NFs), which shifts from being rich in Type III neuronal intermediate filament proteins (nIFs) to progressively favoring Type IV subunits. To characterize the NF composition of developing collateral branches, antibodies to peripherin (a Type III nIF) and NF-M (a Type IV nIF) were used to stain newly differentiating embryonic Xenopus laevis spinal cord neurons in culture. In contrast to what happens in the main axon, staining for both subunits coincided in collaterals. Branches shorter than 10 microm seldom had NFs, whereas all branches longer than 30 microm did. In branches that had NFs staining either extended all the way to branch tip or terminated approximately 10mum from it. These lengths correspond remarkably well with lengths associated with branch stabilization. Given that NFs are the most stable of the cytoskeletal polymers, we speculate that they may contribute to this stabilization. PMID:16725258

Smith, Andrew; Gervasi, Christine; Szaro, Ben G

2006-08-01

154

Audiogram, body mass, and basilar papilla length: correlations in birds and predictions for extinct archosaurs  

Microsoft Academic Search

The inner ear in the group of archosaurs (birds, crocodilians, and extinct dinosaurs) shows a high degree of structural similarity, enabling predictions of their function in extinct species based on relationships among similar variables in living birds. Behavioral audiograms and morphological data on the length of the auditory sensory epithelium (the basilar papilla) are available for many avian species. By

Otto Gleich; Robert J. Dooling; Geoffrey A. Manley

2005-01-01

155

Phase correlation processing for DPIV measurements  

Microsoft Academic Search

A novel digital particle image velocimetry (DPIV) correlation method is presented, the Gaussian transformed phase correlation\\u000a (GTPC) estimator, using nonlinear filtering techniques coupled with the phase-transform (PHAT) generalized cross-correlation\\u000a filter. The use of spatial windowing is shown to be ideally suited for the use of phase correlation estimators, due to their\\u000a invariance to the loss of correlation effects. Error analysis

Adric C. Eckstein; John Charonko; Pavlos Vlachos

2008-01-01

156

A Correlation Between Length of Strong-Shear Neutral Lines and Total X-Ray Brightness in Active Regions  

NASA Technical Reports Server (NTRS)

From a sample of 7 MSFC vector magnetograms,of active regions and 17 Yohkoh SXT soft X-ray images of these active regions, we have found that the total x-ray brightness of an entire active region is correlated with the total length of neutral lines on which the magnetic field is both strong (less than 250 G) and strongly sheared (shear angle greater than 75 deg) in the same active region. This correlation, if not fortuitous, is additional evidence of the importance of strong-shear strong-field neutral lines to strong heating in active regions.

Falconer, D. A.

1997-01-01

157

Simple approach to determining the minimum measurable stress length and stress measurement accuracy in distributed Brillouin sensing  

NASA Astrophysics Data System (ADS)

A simple approach is proposed for quantifying the errors in measuring the Brillouin frequency shifts associated with stresses whose lengths are shorter than the pulse length. The smallest detectable Brillouin frequency shift is thus determined with respect to the size of the stressed sections and the frequency resolution. The lowest detectable frequency shift is found to be ~42% of the Brillouin gain natural linewidth. A worst-case iso-error curve that associates the minimum frequency shift to the length of the stressed region is derived. A minimum resolvable frequency shift and minimum detectable stress length are defined with an approach based on a Rayleigh equivalent criterion.

Ravet, Fabien; Bao, Xiaoyi; Chen, Liang

2005-09-01

158

Simple approach to determining the minimum measurable stress length and stress measurement accuracy in distributed Brillouin sensing.  

PubMed

A simple approach is proposed for quantifying the errors in measuring the Brillouin frequency shifts associated with stresses whose lengths are shorter than the pulse length. The smallest detectable Brillouin frequency shift is thus determined with respect to the size of the stressed sections and the frequency resolution. The lowest detectable frequency shift is found to be approximately 42% of the Brillouin gain natural linewidth. A worst-case iso-error curve that associates the minimum frequency shift to the length of the stressed region is derived. A minimum resolvable frequency shift and minimum detectable stress length are defined with an approach based on a Rayleigh equivalent criterion. PMID:16149353

Ravet, Fabien; Bao, Xiaoyi; Chen, Liang

2005-09-01

159

Audiogram, body mass, and basilar papilla length: correlations in birds and predictions for extinct archosaurs  

Microsoft Academic Search

The inner ear in the group of archosaurs (birds, crocodilians, and extinct dinosaurs) shows a high degree of structural similarity,\\u000a enabling predictions of their function in extinct species based on relationships among similar variables in living birds.\\u000a Behavioral audiograms and morphological data on the length of the auditory sensory epithelium (the basilar papilla) are available\\u000a for many avian species. By

Otto Gleich; Robert J. Dooling; Geoffrey A. Manley

2005-01-01

160

Correlation of the separation region length in shock wave/channel boundary layer interaction  

NASA Astrophysics Data System (ADS)

Results of an experimental investigation of the characteristics of a separation region induced by the interaction of an externally generated oblique shock with the turbulent boundary layer formed in a rectangular half channel are discussed. The experiments were carried out in the supersonic wind tunnel of the Institute of Theoretical and Applied Mechanics SB RAS at a free-stream Mach number M?=3.01 over a range of Reynolds numbers Re1=(9.7-47.5)×106 m-1 and at zero incidence and zero yaw of the model. Particular attention is paid to the size of the zone of the upstream propagation of disturbances (upstream influence region) under different experimental conditions: with varied values of the shock wave strength, half channel width, and Reynolds number. It is shown, in particular, that the normalized upstream influence region length as a function of inclination angle of the shock generator in a rectangular half channel is readily approximated by a simple exponential function. In support of the known reference data obtained for supersonic numbers M? and moderate Re in other configurations, it is also shown that the upstream influence region length decreases with increasing Reynolds number. Generalization of experimental data on the length of the upstream influence region formed in similar geometric configurations is possible using an additional reference linear scale which is the distance from the leading edge of the shock generator to the exposed surface. A substantial dependence of the reference dimensions of separation region on the half channel width is also established.

Kornilov, V. I.

161

Cervical Length Measured by Transvaginal Ultrasonography and Cervicovaginal Infection as Predictor of Preterm Birth Risk  

PubMed Central

Introduction: The study shows possibilities of transvaginal sonographic measurement of the cervix in prediction of premature birth risk. Goals: The aim of the study was to follow up the cervical length in the pregnant from 16th to 37th week, as well as to do a microbiological analysis of the vaginal and cervical flora and to identify relation between the cervical shortening and microbiological flora as well as with a premature birth. Material and methods: The investigation was conducted as a prospective study on two groups of female patients in Clinical Centre of Banja Luka. In the high risk group we had 8% of patients with cervical length bellow than 15mm, 30% of patients with cervical length from 15 to 25m and 62% of patients with cervical length bigger than 25mm. In the low risk group we had no patients with cervical length bellow 15mm, 95% of patients had cervical length bigger than 25mm and 5% of patients had cervical length from 15 do 25mm. Results: The regression coefficient of the cervical length in the high risk group was 0.44mm, while in the low risk group it was 0.26mm. In the high risk group 67.56% patients had a positive cervical smear finding, while in the low risk group it was 4%. A high premature birth (defined as birth before 36.6 weeks) incidence of 50% was presented in patients with cervical length bellow 15mm. In the group of patients with cervical length up to 25mm the premature risk incidence was 10.52±0.05. In the high risk group of patients with a positive cervical smear finding, regarding the cervical length the percentage was as follows; in the subgroup of 15mm length 88,89±11,87, in subgroup from 15 to 25mm was 62,07±11,43 and in the subgroup bigger than 25mm, 60.06±8.05. Conclusion: By the analysis of the first and second goal of our study we can conclude that ultrasound assessment of cervical length is simple and feasible in the 16th week of pregnancy in both groups, with high and low risk. The length of the cervix in this period is shorter in the high risk group compared with the low-risk group. This difference was not statistically significant, however, it clearly demonstrated connection between shorten length of the cervix with the preterm birth. A regression analysis shows that the shortening of the cervix length is more frequent in high risk group which is to be expected, bearing in mind that in this group, the risk of preterm delivery was significantly higher.

Banicevic, Arnela Ceric; Popovic, Miroslav; Ceric, Amela

2014-01-01

162

Length measurement of the eye using a swept-source interferometer.  

PubMed

In this article, a swept-source setup based on a semiconductor optical amplifier at the central wavelength of 1050 nm for measurements of the axial length inside the eye is presented. The large coherence length is achieved using a tunable optical filter, consisting of a reflective diffraction grating, two Littrow prisms, and a scanner. It was possible to achieve a coherence length of 40 mm, which allowed interference measurements in this range to be made. Measurements of the biomedical data of a human model eye are presented. To realize faster measurements, the data acquisition must be increased to more than 2 MS/s. In further studies, the usage of a field-programmable gate array, to achieve faster measurements, will be considered. PMID:24096435

Al-Mohamedi, Haroun; Prinz, Andreas; Mieskes, Guido; Oltrup, Theo; Bende, Thomas

2014-02-01

163

Scanning laser image correlation for measurement of flow  

Microsoft Academic Search

Scanning laser image correlation (SLIC) is an optical correlation technique for measuring the fluid velocity of particles suspended in a liquid. This technique combines laser scanning of an arbitrary pattern with pair cross-correlation between any two points in the pattern. SLIC overcomes many of the limitations of other optical correlation techniques for flow measurement, such as laser speckle, spatial temporal

Molly J. Rossow; William W. Mantulin; Enrico Gratton

2010-01-01

164

The Commissioning Of A Three Dimensional Depolarized Neutron Beamline For Studying The Magnetic Correlation Length Of A Magnetic Material At Tsing Hua Open-Pool Reactor  

SciTech Connect

A new three dimensional neutron depolarization beamline was commissioning at W3 beam port of Tsing Hua Open Pool Reactor (THOR, 2 MW) located in Hsinchu, Taiwan. The beamline consists of a pair of Heusler crystals as neutron polarizer and analyzer. Two three-dimensional rotators were placed before and after the sample position. The sample chamber was enclosed in a mu-metal enclosure with a gradient field at incident and exit ports. Typically, 0.237 nm of monoenergetic neutron was selected for experiments. A flipping ratio of 23 can be obtained which corresponds to a polarization ratio of 92% of this beamline. The typical intensity is 400 n/cm{sup 2}s at 1 MW operation. Magnetic correlation lengths of Ni-ferrite powders with different packing densities were measured to understand the characteristics of this beamline. The magnetic correlation lengths were observed to be 2 mum at virgin state and about 3.1 mum at remanent state. This magnetic correlation length in the virgin state is similar than the particle size. No significant change of domain size at packing density up to 60% implies that the domain wall motion is hindered by the porosity of the sample.

Su, H.-C.; Chang, H.-H.; Hu, C.-W. [Department of Engineering and System Science, National Tsing Hua University, Hsinchu, Taiwan 30013 (China); Lee, C.-H.; Wu, Y.-H. [Department of Engineering and System Science, National Tsing Hua University, Hsinchu, Taiwan 30013 (China); Nuclear Science and Technology Development Center, National Tsing Hua University, Hsinchu, Taiwan 30013 (China); Chang, L. J. [Nuclear Science and Technology Development Center, National Tsing Hua University, Hsinchu, Taiwan 30013 (China); Ioffe, A. [Juelich Centre for Neutron Science (JCNS) Forschungszentrum Juelich Outstation at FRM-II, Lichtenbergstrasse 1, D-85747 Garching (Germany); Kraan, H. T. [Delft University of Technology, Delft (Netherlands)

2010-01-05

165

Clinical value of the correlations of mural coronary artery compression extent with myocardial bridge length and thickness evaluated by 128-slice CT  

PubMed Central

This study aimed to investigate the correlations between the detection rate of mural coronary artery (MCA) by 128-slice CT and the MCA compression extent in systole with myocardial bridge (MB) length and thickness. A retrospective analysis was conducted for 580 patients receiving multislicespiral CT coronary angiography (MSCTCA). In addition, the MCA incidence rate and position were detected, and the MB length and thickness in the left anterior descending branch (LAD) and MCA compression extent in systole were measured to compare the differences between MB-MCA length and thickness among the mild, moderate and severe groups. A total of 140 cases of MB-MCA (24.14%) were involved in the study. Among them, 104 cases occurred in the middle segment of the LAD (74.3%), 16 cases (11.4%) occurred in the distal segment of the LAD, 8 cases (5.7%) occurred in the left circumflex-obtuse marginal branch (LCX-OM), 7 cases (5.0%) occurred in the first diagonal branch (1st D), 3 cases (2.1%) in the intermediate branch (M) and 2 cases (1.5%) occurred in the posterior descending branch of the right coronary artery (RCA-PD). The mean length of the MB in the LAD was 21.80±5.98 mm, the mean thickness was 2.15±0.74 mm and the mean compression extent was 38.5±19.6%. Among the different groups, there were no significant difference in MB length (P>0.05) but there were significant differences in MB thickness (P<0.05). In addition, the extent of MCA compression in systole was linearly and positively correlated with MB thickness (r=0.408, P<0.05) but was not correlated with MB length (r=0.076, P>0.05). 128-slice CT coronary angiography (SCTCA) is able to accurately detect MB-MCA and evaluate the correlations of MCA compression extent in systole with MB length and thickness which provides a basis for its clinical use.

NIU, YU-JUN; ZHANG, XIANG-LIN; CAO, A-DAN; LENG, BING

2013-01-01

166

Focal length measurement of microlens array for Shack-Hartmann wavefront sensor using interferometer  

NASA Astrophysics Data System (ADS)

We have proposed a method to determine the focal length of microlens array (MLA) based on the measurement of transverse displacement of image spot in the focal plane for a change of angle of incidence of plane wavefront. An existing interferometer test setup, meant for the surface figure measurement of MLA substrate, along with a charge-coupled device (CCD) is used for this purpose. The interferometer generates as well as measures the angle of incidence of plane wavefront at the MLA, and the transverse displacement of the image spot is determined from images recorded with the CCD. We have also discussed the theory of estimation of the focal length of MLA with spherical wavefront. Error analysis is carried out for both methods and is compared. The proposed plane wavefront method is experimentally demonstrated with an off-the-shelf MLA, and the measured focal length is within 1% of catalogue value.

Kumar, M. Senthil; Narayanamurthy, C. S.; Kumar, A. S. Kiran

2013-12-01

167

Stern potential and Debye length measurements in dilute ionic solutions with electrostatic force microscopy.  

PubMed

We demonstrate the ability to measure Stern potential and Debye length in dilute ionic solution with atomic force microscopy. We develop an analytic expression for the second harmonic force component of the capacitive force in an ionic solution from the linearized Poisson-Boltzmann equation. This allows us to calibrate the AFM tip potential and, further, obtain the Stern potential of sample surfaces. In addition, the measured capacitive force is independent of van der Waals and double layer forces, thus providing a more accurate measure of Debye length. PMID:24076615

Kumar, Bharat; Crittenden, Scott R

2013-11-01

168

Stern potential and Debye length measurements in dilute ionic solutions with electrostatic force microscopy  

NASA Astrophysics Data System (ADS)

We demonstrate the ability to measure Stern potential and Debye length in dilute ionic solution with atomic force microscopy. We develop an analytic expression for the second harmonic force component of the capacitive force in an ionic solution from the linearized Poisson-Boltzmann equation. This allows us to calibrate the AFM tip potential and, further, obtain the Stern potential of sample surfaces. In addition, the measured capacitive force is independent of van der Waals and double layer forces, thus providing a more accurate measure of Debye length.

Kumar, Bharat; Crittenden, Scott R.

2013-11-01

169

Optical length change measurement via RF frequency shift analysis of incoherent light source based optoelectronic oscillator.  

PubMed

Radio-frequency (RF) frequency shift of incoherent light source based optoelectronic oscillator (OEO) is employed to measure the optical length change. In the proposed OEO using an incoherent light source, the optical length under test is inserted in the optoelectronic hybrid loop. The frequency shift of RF oscillation modes at the output of the OEO reflects the optical length change, with the change being measured via frequency shift analysis. Two OEO configurations are theoretically designed and experimentally performed, while an amplified spontaneous emission (ASE) source serves as the incoherent light source. A linear relationship between the frequency shift and the optical length change has been confirmed for measurement, and a reconfigurable measurement sensitivity is available by selecting different oscillation modes. Moreover, the use of ASE greatly reduces the complexity and the cost for stabilization control on light source, while the derived results are consistent with that obtained in a laser source based OEO both in the measured optical length changes and the phase noise performance. A sensitivity of -28 KHz/cm, -480 KHz/cm or higher, and a resolution of nano-meter scale are obtained, which can be used to monitor the displacement, the changes in refractive index, temperature. PMID:24921811

Zou, Xihua; Li, Ming; Pan, Wei; Luo, Bin; Yan, Lianshan; Shao, Liyang

2014-05-01

170

Electronic root canal length measurement before and after experimentally induced pulpitis and apical periodontitis in dogs  

Microsoft Academic Search

The aim of the study was to examine the influence of the state of the pulp and apical periodontium on the results of electronic root canal length measurement (ERCLM) with a resistance measuring device in dogs. Pulpitis and apical periodontitis were induced by pulp exposure and contamination by the oral flora in the premolar teeth of six mongrel dogs, comprising

Maja Kovacevic; Tomislav Tamarut; Snjezana Glavicic; Nives Jonjic; Sanja Zoricic-Cvek; Dragica Bobinac

2006-01-01

171

Possible methods of measuring the length of sub-picosecond electron bunches in the frequency domain  

SciTech Connect

The traditional method of measuring extremely short electron beams using streak cameras begins to become problematic and expensive at bunch lengths at a picosecond and below. In this paper a few alternatives, based on the differential measurement of the Fourier spectrum of the longitudinal charge distribution of a bunch are suggested and evaluated.

Jackson, G.P.

1992-12-01

172

Bunch length measurements at the Advanced Photon Source (APS) linear accelerator.  

National Technical Information Service (NTIS)

Measurements of the APS linac micro-bunch length are performed by backphasing a single 2856-MHz, S-band linac waveguide and using a downstream spectrometer to observe the beam. By measuring the beam width in the dispersive plane as a function of rf power ...

N. S. Sereno R. Fuja C. Gold A. E. Grelick A. Nassiri

1995-01-01

173

Effects of Text Length on Lexical Diversity Measures: Using Short Texts with Less than 200 Tokens  

ERIC Educational Resources Information Center

Despite the importance of lexical diversity (LD) in L2 speaking and writing performance, LD assessment measures are known to be affected by the number of words analyzed in the text. This study aims to identify LD measures that are least affected by text length and can be used for the analysis of short L2 texts (50-200 tokens). We compared the…

Koizumi, Rie; In'nami, Yo

2012-01-01

174

Measuring minority-carrier diffusion length using a Kelvin probe force microscope  

Microsoft Academic Search

A method based on Kelvin probe force microscopy for measuring minority-carrier diffusion length in semiconductors is described. The method is based on measuring the surface photovoltage between the tip of an atomic force microscope and the surface of an illuminated semiconductor junction. The photogenerated carriers diffuse to the junction and change the contact potential difference between the tip and the

R. Shikler; N. Fried; T. Meoded; Y. Rosenwaks

2000-01-01

175

Acoustic method for measuring the sound speed of gases over small path lengths  

Microsoft Academic Search

Acoustic ``phase shift'' methods have been used in the past to accurately measure the sound speed of gases. In this work, a phase shift method for measuring the sound speed of gases over small path lengths is presented. We have called this method the discrete acoustic wave and phase detection (DAWPD) method. Experimental results show that the DAWPD method gives

J. S. Olfert; M. D. Checkel; C. R. Koch

2007-01-01

176

Air method measurements of apple vessel length distributions with improved apparatus and theory  

Microsoft Academic Search

Studies showing that rootstock dwarfing potential is related to plant hydraulic conductance led to the hypothesis that xylem properties are also related. Vessel length distribution and other properties of apple wood from a series of varieties were measured using the 'air method' in order to test this hypoth- esis. Apparatus was built to measure and monitor conductivity to air of

Shabtai Cohen; John Bennink; Mel Tyree

2003-01-01

177

A general framework for error analysis in measurement-based GIS Part 4: Error analysis in length and area measurements  

Microsoft Academic Search

This is the final of a series of four papers on the development of a general framework for error analysis in measurement-based geographic information systems (MBGIS). In this paper, we discuss the error analysis problems in length and area measurements under measurement error (ME) of the defining points. In line with the basic ME model constructed in Part 1 of

Yee Leung; Jiang-Hong Ma; Michael F. Goodchild

2004-01-01

178

Development of a method for the measurement of primary cilia length in 3D  

PubMed Central

Background Primary cilia length is an important measure of cell and tissue function. While accurate length measurements can be calculated from cells in 2D culture, measurements in tissue or 3D culture are inherently difficult due to optical distortions. This study uses a novel combination of image processing techniques to rectify optical distortions and accurately measure cilia length from 3D images. Methods Point spread functions and experimental resolutions were calculated from subresolution microspheres embedded in 3D agarose gels for both wide-field fluorescence and confocal laser scanning microscopes. The degree of axial smearing and spherical aberration was calculated from xy:xz diameter ratios of 3D image data sets of 4 ?m microspheres that had undergone deconvolution and/or Gaussian blurring. Custom-made 18 and 50 ?m fluorescent microfibers were also used as calibration objects to test the suitability of processed image sets for 3D skeletonization. Microfiber length in 2D was first measured to establish an original population mean. Fibers were then embedded in 3D agarose gels to act as ciliary models. 3D image sets of microfibers underwent deconvolution and Gaussian blurring. Length measurements within 1 standard deviation of the original 2D population mean were deemed accurate. Finally, the combined method of deconvolution, Gaussian blurring and skeletonization was compared to previously published methods using images of immunofluorescently labeled renal and chondrocyte primary cilia. Results Deconvolution significantly improved contrast and resolution but did not restore the xy:xz diameter ratio (0.80). Only the additional step of Gaussian blurring equalized xy and xz resolutions and yielded a diameter ratio of 1.02. Following image processing, skeletonization successfully estimated microfiber boundaries and allowed reliable and repeatable measurement of fiber lengths in 3D. We also found that the previously published method of calculating length from 2D maximum projection images significantly underestimated ciliary length. Conclusions This study used commercial and public domain image processing software to rectify a long-standing problem of 3D microscopy. We have shown that a combination of deconvolution and Gaussian blurring rectifies optical distortions inherent in 3D images and allows accurate skeletonization and length measurement of microfibers and primary cilia that are bent or curved in 3D space.

2012-01-01

179

The Physical Ability of Japanese Female Elderly with Cerebrovascular Disease Correlates with the Telomere Length and Subtelomeric Methylation Status in Their Peripheral Blood Leukocytes  

Microsoft Academic Search

Background: The telomere length and subtelomeric methylated status of peripheral blood leukocytes have been reported to be correlated with many kinds of pathophysiological conditions. However, the correlation between the telomeric parameters and patients’ physical ability is not known. Objective: This study aims to study how telomeric parameters, including telomere length and the subtelomeric methylation status of peripheral blood leukocytes, are

Toyoki Maeda; Jun-ichi Oyama; Yoshihiro Higuchi; Yasuhiro Nishiyama; Yoshihiro Kudo; Tomoko Yamori; Takashi Nakazono; Takahiro Arima; Koshi Mimori; Naoki Makino

2011-01-01

180

Bunch Length Measurements at the JLab FEL Using Coherent Transition and Synchrotron Radiation  

SciTech Connect

The JLab FEL is routinely operated with sub-picosecond bunches. The short bunch length is important for high gain of the FEL. Coherent transition radiation has been used for the bunch length measurements for many years [1]. This diagnostic can be used only in the pulsed beam mode. It is our goal to run the FEL with CW beam and a 74.85 MHz micropulse repetition rate, which, with the 135 pC nominal bunch charge corresponds to the beam average current of 10 mA. Hence it is very desirable to have the possibility of making bunch length measurements when running CW beam with any micropulse frequency. We use a Fourier transform infrared (FTIR) interferometer, which is essentially a Michelson interferometer, to measure the spectrum of the coherent synchrotron radiation generated in the last dipole of the magnetic bunch compressor upstream of the FEL wiggler. This noninvasive diagnostic provides bunch length measurements for CW beam operation at any micropulse frequency. We also compare the measurements made with the help of the FTIR interferometer with data obtained using the Martin-Puplett interferometer [1]. Results of the two diagnostics agree within 15 %. Here we present a description of the experimental setup, data evaluation procedure and results of the beam measurements.

Pavel Evtushenko; James Coleman; Kevin Jordan; J. Michael Klopf; George Neil; Gwyn Williams

2006-05-01

181

First working group meeting on the minority carrier diffusion length/lifetime measurement: Results of the round robin lifetime/diffusion length tests  

SciTech Connect

As was noted in the cover letter that accompanied the samples, the eleven bare silicon samples were from various manufacturers. Table I lists the codes for the samples and the manufacturer of each sample. It also notes if the sample was single or poly-crystalline. The samples had been polished on one side before being sent out for measurements, but no further processing was done. The participants of the study were asked to measure either the lifetime or diffusion length of each of the samples using their standard procedure. Table II shows the experimental conditions used by the groups who measured diffusion length. All the diffusion length measurements were performed using the Surface Photovoltage method (SPV). Table M shows the experimental conditions for the lifetime measurements. All the lifetime measurements were made using the Photoconductance Decay method (PCD) under low level injection. These tables show the diameter of the spot size used during the measurement (the effective sampling area), the locations where measurements were taken, and the number of measurements taken at each location. Table N shows the results of the measurements. The table is divided into diffusion length and lifetime measurements for each sample. The values listed are the average values reported by each group. One of the immediate artifacts seen in the data is the large variation in the lifetime measurements. The values from MIT and Mobil are generally close. However, the measurements from NCSU are typically an order of magnitude lower.

Cudzinovic, M.; Sopori, B. [comp.] [comp.

1995-11-01

182

Longitudinal-to-Transverse Mapping for Femtosecond Electron Bunch Length Measurement  

SciTech Connect

A longitudinal-to-transverse mapping technique is proposed to measure the length and temporal profile of ultrashort electron bunches. In this scheme a special chicane and a radio-frequency deflecting cavity are used to transform the beam's longitudinal distribution into angular distribution which is further converted to transverse distribution after a parallel-to-point imaging beam line. With this technique, the temporal profile of the electron beam is exactly mapped to the transverse profile. This makes it possible to measure ultrashort electron bunch length with a resolution well beyond 1 femtosecond.

Xiang, Dao; Ding, Yuantao; /SLAC

2010-08-25

183

Interpretation of scanning electron microscope measurements of minority carrier diffusion lengths in semiconductors  

NASA Technical Reports Server (NTRS)

In scanning electron microscope (SEM) injection measurements of minority carrier diffusion lengths some uncertainties of interpretation exist when the response current is nonlinear with distance. This is significant in epitaxial layers where the layer thickness is not large in relation to the diffusion length, and where there are large surface recombination velocities on the incident and contact surfaces. An image method of analysis is presented for such specimens. A method of using the results to correct the observed response in a simple convenient way is presented. The technique is illustrated with reference to measurements in epitaxial layers of GaAs. Average beam penetration depth may also be estimated from the curve shape.

Flat, A.; Milnes, A. G.

1978-01-01

184

On the neural origin of pseudoneglect: EEG-correlates of shifts in line bisection performance with manipulation of line length?  

PubMed Central

Healthy participants tend to show systematic biases in spatial attention, usually to the left. However, these biases can shift rightward as a result of a number of experimental manipulations. Using electroencephalography (EEG) and a computerized line bisection task, here we investigated for the first time the neural correlates of changes in spatial attention bias induced by line-length (the so-called line-length effect). In accordance with previous studies, an overall systematic left bias (pseudoneglect) was present during long line but not during short line bisection performance. This effect of line-length on behavioral bias was associated with stronger right parieto-occipital responses to long as compared to short lines in an early time window (100–200 ms) post-stimulus onset. This early differential activation to long as compared to short lines was task-independent (present even in a non-spatial control task not requiring line bisection), suggesting that it reflects a reflexive attentional response to long lines. This was corroborated by further analyses source-localizing the line-length effect to the right temporo-parietal junction (TPJ) and revealing a positive correlation between the strength of this effect and the magnitude by which long lines (relative to short lines) drive a behavioral left bias across individuals. Therefore, stimulus-driven left bisection bias was associated with increased right hemispheric engagement of areas of the ventral attention network. This further substantiates that this network plays a key role in the genesis of spatial bias, and suggests that post-stimulus TPJ-activity at early information processing stages (around the latency of the N1 component) contributes to the left bias.

Benwell, Christopher S.Y.; Harvey, Monika; Thut, Gregor

2014-01-01

185

System for variable stripe length optical gain measurements in structures containing silicon nanocrystals  

NASA Astrophysics Data System (ADS)

The variable stripe length (VSL) is a convenient method for the measurement of optical gain. However, several inherent experimental constraints such as pump beam non-uniformity, diffraction from the movable cache and sample edges, and gain saturation challenge its proper implementation. A modified VSL configuration, which addresses these constraints, has been developed and implemented for gain measurements in SiO2 structures containing silicon nanocrystals. A microprocessor based acquisition of several control parameters provides reliable and reproducible optical gain measurements.

Koshel, D.; Barba, D.; Martin, F.; Ross, G. G.

2009-06-01

186

Improvement in the measurement of focal length using spot patterns and spherical aberration.  

PubMed

Using an optical setup that includes a square array of 3×3 holes, we used nine meridional rays to measure the effective focal length of a lens. We observed the selected meridional rays as a spot pattern on a diffuse screen. First, we generated a regular square spot pattern (reference pattern) without a lens to test, and then we generated two spot patterns in two different axial positions when the lens being tested refracts the rays. By selecting two sets of four rays of each spot pattern, we were able to measure the difference of the longitudinal (primary) spherical aberration in two positions. With this difference we were able to improve the calculation of the effective focal length. To determine the method's precision, we first simulated the relative error in the effective focal length considering the error in the measurement of the ray heights. Then we determined the experimental relative error by means of the standard deviation of the focal lengths obtained for each spot (in the image of reference and for the images at the two different locations) for both sets of four spots. The experimental results agree very well with the simulation. The error analysis allows us to establish under what conditions it is possible to obtain relative errors of less than 1% in the effective focal length. PMID:23938404

Mejía, Yobani

2013-08-10

187

Focal length measurement of a varifocal liquid lens with capacitance detection  

NASA Astrophysics Data System (ADS)

This paper reports on a detailed deformation model of varifocal liquid lenses fabricated by Parylene-on-liquid-deposition (POLD), which can be applied to measure and adjust the focal length of such lenses without using extra sensors or sensing mechanisms. The lens was fabricated by encapsulating a liquid between a transparent electrode and a polymer film that was covered with a metal electrode. When voltage is applied to the two electrodes, the lens deforms due to the electrostatic force, and its focal length and the capacitance between the two electrodes change simultaneously. This characteristic enables the focal length of the lens to be adjusted and detected by measuring the capacitance change. The focal length of the fabricated varifocal liquid lens changed from 153.6 to 82.6 mm by applying 150-V. The focal length change of the liquid lens was calculated from the change in its capacitance. Finally, to confirm the efficiency of this varifocal liquid lens, we fabricated a confocal distance sensor using the lens for laser scanning and demonstrated that this system can be used to measure distances of 94-140 mm with an average error of 0.83 mm and a standard deviation of 0.77 mm.

Noda, Kentaro; Binh-Khiem, Nguyen; Takei, Yusuke; Takahata, Tomoyuki; Matsumoto, Kiyoshi; Shimoyama, Isao

2014-04-01

188

Measurement of bunch length in Indus-1 storage ring using fast photodiode.  

PubMed

The length of electron bunches in a storage ring is an important parameter for both synchrotron radiation users and accelerator physicists. Several methods are used for measurements of bunch length using electronic and optical instruments. We have measured temporal profile of synchrotron radiation emitted from dipole magnet of Indus-1 by using fast photodiode. Bunch length is calculated by assuming gaussian profile for the particles inside bunch. The results show that bunch length is increasing with the decrease of gap voltage of RF cavity. These measurements were carried out at low beam current; at high voltage results are in close agreement with theory and the values estimated using ZAP code. In the second experiment, the results show that bunch length increases with the increase of beam current inside the bunch, and above threshold current, it follows Chao-Gareyte scaling law. The longitudinal broadband impedance for Indus-1 SRS was estimated using Keil-Schnell criterion and results were compared with theoretical estimated values using ZAP code. PMID:23206055

Garg, Akash Deep; Nathwani, R K; Holikatti, A C; Karnewar, Akhilesh Kumar; Tyagi, Y; Yadav, S; Puntambekar, T A; Navathe, C P

2012-11-01

189

Field measurements to support IAEA procedures development for fuel assembly and fuel rod active length verification  

SciTech Connect

The activities performed in verification of reactor fuel rods and assemblies by International Atomic Energy Agency (IAEA) safeguards inspectors include measurements of the length of the enriched uranium sections in fuel assemblies and fuel rods. These measurements are normally made with the IAEA hand-held gamma monitor (HM-4) on fuel elements containing only enriched uranium. Many fuel rods currently in use contain natural uranium end sections and several different [sup 235]U enrichment zones. To support development of standard procedures for IAEA nondestructive assay (NDA) measurements, a field measurement campaign was carried out to evaluate the FM-4 measurements and to investigate the feasibility of extending the HM-4 measurements to fuel rods and assemblies containing both natural and enriched uranium sections. The results show that the enriched fuel length can be measured to within [plus minus] 1 to 2 cm in the presence of natural uranium sections and to within [plus minus] 0.5 = when only enriched uranium is present. Based on the results from these measurements, a standard procedure, Measurement of Active Fuel Length in Fuel Assemblies and Fuel Rods Using the HM-4,'' has been drafted for review by the IAEA.

Belew, W.L.; Cooley, J.N.; Whitaker, J.M.

1992-07-17

190

Field measurements to support IAEA procedures development for fuel assembly and fuel rod active length verification  

SciTech Connect

The activities performed in verification of reactor fuel rods and assemblies by International Atomic Energy Agency (IAEA) safeguards inspectors include measurements of the length of the enriched uranium sections in fuel assemblies and fuel rods. These measurements are normally made with the IAEA hand-held gamma monitor (HM-4) on fuel elements containing only enriched uranium. Many fuel rods currently in use contain natural uranium end sections and several different {sup 235}U enrichment zones. To support development of standard procedures for IAEA nondestructive assay (NDA) measurements, a field measurement campaign was carried out to evaluate the FM-4 measurements and to investigate the feasibility of extending the HM-4 measurements to fuel rods and assemblies containing both natural and enriched uranium sections. The results show that the enriched fuel length can be measured to within {plus_minus} 1 to 2 cm in the presence of natural uranium sections and to within {plus_minus} 0.5 = when only enriched uranium is present. Based on the results from these measurements, a standard procedure, ``Measurement of Active Fuel Length in Fuel Assemblies and Fuel Rods Using the HM-4,`` has been drafted for review by the IAEA.

Belew, W.L.; Cooley, J.N.; Whitaker, J.M.

1992-07-17

191

A new Coulomb correction method for Bose-Einstein correlations, based on the + correlation measurements  

Microsoft Academic Search

We present the measured correlation functions for + , and ++ pairs in central S+Ag collisions at 200 GeV per nucleon. The Gamov function, which has been traditionally used to correct the correlation functions of charged pions for the Coulomb interaction, is found to be inconsistent with all measured correlation functions. Cer- tain problems which have been dominating the systematic

T. Alber; J. Bartke; H. Bialkowska; M. A. Bloomer; R. Bock; W. J. Braithwaite; D. Brinkmann; R. Brockmann; P. Bun; P. Chan; S. I. Chase; P. B. Cramer; J. G. Cramer; I. Derado; B. Eberlein; V. Eckardt; J. Eschke; D. Ferenc; B. Fleischmann; P. Foka; P. Freund; M. Fuchs; E. Gladysz; J. W. Harris; M. Hoffmann; P. Jacobs; S. Kabana; K. Kadija; J. Kosiec; M. Kowalski; M. Lahanas; J. Y. Lee; A. Ljubi; S. Margetis; J. T. Mitchell; R. Morse; E. Nappi; G. Odyniec; G. Paic; A. D. Panagiotou; A. Petridis; A. Piper; F. Posa; A. M. Poskanzer; H. G. Pugh; G. Rai; W. Rauch; R. Renfordt; W. Retyk; G. Roland; H. Rothard; K. Runge; A. Sandoval; J. Schambach; N. Schmitz; E. Schmoetten; I. Schneider; R. Sendelbach; P. Seyboth; J. Seyerlein; E. Skrzypczak; P. Stefansky; L. Teitelbaum; S. Tonse; T. A. Trainor; G. Vasileiadis; M. Vassiliou; S. Wenig; M. Wensveen; B. Wosiek

1997-01-01

192

Does the orbit-averaged theory require a scale separation between periodic orbit size and perturbation correlation length?  

SciTech Connect

Using the canonical perturbation theory, we show that the orbit-averaged theory only requires a time-scale separation between equilibrium and perturbed motions and verifies the widely accepted notion that orbit averaging effects greatly reduce the microturbulent transport of energetic particles in a tokamak. Therefore, a recent claim [Hauff and Jenko, Phys. Rev. Lett. 102, 075004 (2009); Jenko et al., ibid. 107, 239502 (2011)] stating that the orbit-averaged theory requires a scale separation between equilibrium orbit size and perturbation correlation length is erroneous.

Zhang, Wenlu [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China) [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Department of Physics and Astronomy, University of California, Irvine, California 92697 (United States); Lin, Zhihong [Department of Physics and Astronomy, University of California, Irvine, California 92697 (United States) [Department of Physics and Astronomy, University of California, Irvine, California 92697 (United States); Fusion Simulation Center, Peking University, Beijing 100871 (China)

2013-10-15

193

Alignment and arm length measurement of the swing arm profilometer using a laser tracker  

NASA Astrophysics Data System (ADS)

In this paper, we present the use of the laser tracker to aid the alignment of a Swing Arm Profilometer (SAP) and measure the length of the swinging arm, thus calibrating the operating radius of the SAP. The measurement uncertainty analysis is given. A laser tracker is used to align the SAP to ensure the path of the probe head passes through the rotary axis of the rotary table. By building the coordinate system by laser tracker measurement on the rotary table and measuring the swinging arc of the arm, we can determine whether the swinging path of the probe head passes through the rotary axis of the rotary table and perform the corresponding adjustment if necessary. A laser tracker is also used to measure the arm length, i.e. the length between the probe's ball centre and the rotation axis of the swinging arm. By placing a retroreflector or the tracker ball on the swinging arm and scanning the swinging path of the arm using the laser tracker, we can acquire the data of an arc and fit to determine the length of the probe head center to rotation axis of swinging arm, thus giving accurate SAP calibration data.

Jing, Hongwei; King, Christopher; Walker, David

2010-05-01

194

CTR Bunch Length Measurement of Monoenergetic and Maxwellian Electron Beams from Laser Plasma Cathode  

SciTech Connect

Recently, several plasma cathodes at universities and institutes can generate a monoenergetic electron beam. LBL measured the bunch length by the CTR (Coherent Transition Radiation) interferometer to determine it as about 50 fs (FWHM). We are trying to carry out a single-shot measurement of the bunch length by a infrared polychromator. As the first step forward it, we measured the CTR spectra emitted at a 300microm-thick Ti foil by the electron beams from our plasma cathode. The laser parameters are 12 TW, 50fs, 3x1019W/cm2. He gas-jet is used and the electron density is 6x1019cm-3. By using the liquid He bolometer and several optical low-pass filter, we measured the spectra of the CTR. We can clearly classify the difference of the spectrum and bunch length for the monoenergetic and Maxwellian beams. The numerical analysis of the bunch elongation due to the energy spread confirms the experimental results. The bunch length of the monoenergetic beam is less than 100 fs at FWHM with about 10 pC per bunch, which is consistent with the PIC simulation. The next single-shot measurement with the FIR (Far-Ingfra-Red) polychomator and application to a pump-and-probe experiment for radiation chemsitry are also discussed.

Uesaka, Mitsuru; Maekawa, Akira; Tsujii, Ryosuke; Kinoshita, Kennichi; Atsushi, Yamazaki; Kobayashi, Kazuyuki; Shibata, Yukio; Kondo, Yasuhiro [Nuclear Professional School, University of Tokyo, 2-22 Shirakata-Shirane, Tokai, Naka, Ibaraki 319-1188 (Japan); Ohkubo, Takeru [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency, 1233 Watanuki-machi, Takasaki, Gunma (Japan); Hosokai, Tomonao [Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo (Japan); Zhidkov, Alexei [Central Research Institute of Electric Power Industry, 2-6-1 Nagasaka, Yokosuka, Kanagawa (Japan); Takahashi, Toshiharu [Kyoto University Research Reactor Institute, 2 Asahiro-nishi, Kumatori, Sennan, Osaka (Japan)

2006-11-27

195

Focal length measurement of microlens-array by the clarity function of digital image  

NASA Astrophysics Data System (ADS)

In this paper, a method for the focal length measurement of Microlens-array (MLA) is introduced. The measuring setup is composed by monochromatic, condenser, collimator, MLA, microscope and CCD sensor. An experiment was performed using a MLA whose focal length is about 8 mm and a GUI based on Matlab software was developed to analyze the image gathered at the vertex and the focus by the clarity of digital image processing technology. The measuring uncertainty of this method is about 0.8% and this method introduced in this paper can finish tens of microlens array measurement at a single shot. Compared with traditional technology for MLA measuring, this method not only has a preferable precision but also super efficiency.

Zhu, Xianchang; Wu, Fan; Cao, Xuedong; Wu, Shibin; Zhang, Peng; Jing, Hongwei

2012-10-01

196

Lifetime and diffusion length measurements on silicon material and solar cells  

NASA Technical Reports Server (NTRS)

Experimental methods were evaluated for the determination of lifetime and diffusion length in silicon intentionally doped with potentially lifetime-degrading impurities found in metallurgical grade silicon, impurities which may be residual in low-cost silicon intended for use in terrestrial flat-plate arrays. Lifetime measurements were made using a steady-state photoconductivity method. Diffusion length determinations were made using short-circuit current measurements under penetrating illumination. Mutual consistency among all experimental methods was verified, but steady-state photoconductivity was found preferable to photoconductivity decay at short lifetimes and in the presence of traps. The effects of a number of impurities on lifetime in bulk material, and on diffusion length in cells fabricated from this material, were determined. Results are compared with those obtained using different techniques. General agreement was found in terms of the hierarchy of impurities which degrade the lifetime.

Othmer, S.; Chen, S. C.

1978-01-01

197

Photon path length distributions inferred from rotating shadowband spectrometer measurements at the Atmospheric Radiation Measurements Program Southern Great Plains site  

Microsoft Academic Search

An algorithm for retrieving the first two moments of the photon path length probability density function for both the oxygen A-band and the 0.820 mum water vapor band from measurements of the second generation Rotating Shadowband Spectrometer (RSS) is developed and applied to data from the Atmospheric Radiation Measurements (ARM) Program Southern Great Plains (SGP) site. In the algorithm, solar

Qilong Min; Eugene E. Clothiaux

2003-01-01

198

Photon path length distributions inferred from rotating shadowband spectrometer measurements at the Atmospheric Radiation Measurements Program Southern Great Plains site  

Microsoft Academic Search

An algorithm for retrieving the first two moments of the photon path length probability density function for both the oxygen A-band and the 0.820 ?m water vapor band from measurements of the second generation Rotating Shadowband Spectrometer (RSS) is developed and applied to data from the Atmospheric Radiation Measurements (ARM) Program Southern Great Plains (SGP) site. In the algorithm, solar

Qilong Min; Eugene E. Clothiaux

2003-01-01

199

A strong correlation exists between the distribution of retinal ganglion cells and nose length in the dog.  

PubMed

The domestic dog, CANIS LUPUS FAMILIARIS, is a subspecies of the gray wolf, CANIS LUPUS, with almost identical mitochondrial DNA. The dog is the most diverse species on earth, with skull length varying between 7 and 28 cm whereas the wolf skull is around 30 cm long. However, eye size in dogs does not appear to vary as much. For example, small dogs such as the chihuahua appear to have very large eyes in proportion to the skull. Our aim was to examine eye size and retinal cell numbers and distribution to determine whether the dog eye exhibits as much variation as the skull. We found a correlation between eye radius and skull dimensions. However, the most surprising finding was that the distribution of ganglion cells in the eye varied tremendously from a horizontally aligned visual streak of fairly even density across the retina (as seen in the wolf) to a strong area centralis with virtually no streak (for example, as observed in a pug from the current series). This variation in ganglion cell density within a single species is quite unique. Intriguingly, the ratio of peak ganglion cell density in the area centralis to visual streak was highly negatively correlated with skull length (r = -0.795, n = 22) and positively correlated with cephalic index (r = 0.687, n = 22). The orientation of eyelid aperture was also correlated with cephalic index (r = 0.648, n = 22). Therefore, the genetic manipulation of selective breeding, which has produced an abnormal shortening of the skull and eyelids with less lateral apertures, has also produced a considerably more pronounced area centralis in the dog. PMID:14673195

McGreevy, Paul; Grassi, Tanya D; Harman, Alison M

2004-01-01

200

Multichannel analysis of correlation length of SEVIRI images around ground-based cloud observatories to determine their representativeness  

NASA Astrophysics Data System (ADS)

Images of the geostationary Meteosat-9 SEVIRI instrument during the year 2012 are analyzed with respect to the representativeness of the observations of eight cloud observatories in Europe. Cloudy situations are selected to get a time series for every pixel in a 300 km × 300 km area centered around each ground station. Then the Pearson correlation coefficient of each time series to the one of the pixel nearest to the corresponding ground site is calculated. The area for which a station is representative is defined by the characteristic radius around each station for each SEVIRI channel, where the average correlation falls below 0.9. It is found that measurements in the visible and near infrared channels, which respond to cloud microphysics, are correlated in an area with a 1 to 4 km radius, while the thermal channels, that correspond to cloud top temperature, are correlated to a distance of about 20 km. The defined radius even increases for the water vapor and ozone channels. While all stations in Central Europe are quite alike, the correlations around the station in the mountains of southern Italy are much lower. Additionally correlations at different distances corresponding to the grid box sizes of forecast models were compared. The results show good comparability between regional forecast models (grid size ≲ 10 km) and ground-based measurements since the correlations in less than 10 km distance are in all cases higher than 0.8. For larger distances like they are typical for global models (grid size ≳ 20 km) the correlations decrease to 0.6, especially for shortwave measurements and corresponding cloud products. By comparing daily means, the characteristic radius of each station is increased to about 3 to 10 times the value of instantaneous measurements and also the comparability to models grows.

Slobodda, J.; Hünerbein, A.; Lindstrot, R.; Preusker, R.; Ebell, K.; Fischer, J.

2014-06-01

201

Method for Single-Shot Measurement of Picosecond Laser Pulse-Lengths Without Electronic Time Dispersion.  

National Technical Information Service (NTIS)

A two-source shear pattern recording is proposed as a method for single-shot measurement of the pulse shape from nearly monochromatic sources whose pulse lengths are shorter than their coherence times. The basis of this method relies on the assertion that...

G. A. Kyrala

1987-01-01

202

Measurement of the length of pedestrian crossings - a navigational aid for blind people  

Microsoft Academic Search

This paper describes a fast as well as simple method for measurement of the length of pedestrian crossings using a single camera for the purpose of a travel aid for blind people. In a crossing, the usual black road surface is painted with constant width periodic white lines. In Japan, this width is 45 cm. The crossing region as well

Mohammad Shorif Uddin; Tadayoshi Shioyama

2004-01-01

203

Curricular Treatments of Length Measurement in the United States: Do They Address Known Learning Challenges?  

ERIC Educational Resources Information Center

Extensive research has shown that elementary students struggle to learn the basic principles of length measurement. However, where patterns of errors have been documented, the origins of students' difficulties have not been identified. This study investigated the hypothesis that written elementary mathematics curricula contribute to the…

Smith, John P., III; Males, Lorraine M.; Dietiker, Leslie C.; Lee, KoSze; Mosier, Aaron

2013-01-01

204

Systematic Pseudomagnetic Measurements of the Spin-Dependent Scattering Length of Slow Neutrons with Atomic Nuclei  

NASA Astrophysics Data System (ADS)

The magnitude and the sign of spin-dependent scattering lengths of slow neutrons by nuclei of Li7, Al27, Sc45, Zr91, Nb93, La139, and Ta181 have been determined by measuring the dependence of the precession angle of the neutron spins on the nuclear polarization of the scattering target.

Roubeau, P.; Abragam, A.; Bacchella, G. L.; Glättli, H.; Malinovski, A.; Meriel, P.; Piesvaux, J.; Pinot, M.

1974-07-01

205

Measurement of Optical Path Length for Cerebral Near-Infrared Spectroscopy in Newborn Infants  

Microsoft Academic Search

The time taken for an extremely short pulse of near-infrared laser light to traverse the heads of 6 preterm infants was measured after death. The values obtained were used to calculate a differential path length factor (DPF), defined as the mean distance travelled by the photons divided by the distance between the points where light entered and left the head.

J. S. Wyatt; M. Cope; D. T. Delpy; P. van der Zee; S. R. Arridge; A. D. Edwards; E. O. R. Reynolds

1990-01-01

206

The testing of heliograph mirrors and the measurement of mirrors of long focal length  

Microsoft Academic Search

The method of testing the general surface consists in observing the reflection from the mirror of a system of squares on the test board, the magnification given by the mirror being utilised to determine the curvature. The method of examination is applicable to the rapid measurement of mirrors of long focal length, especially of those forms silvered on the back,

Wm Shackleton

1921-01-01

207

Bunch Length Measurements at the ATF Damping Ring in April 2000.  

National Technical Information Service (NTIS)

We want to accurately know the energy spread and bunch length dependence on current in the ATF damping ring. One reason is to know the strength of the impedance: From the energy spread measurements we know whether or not we are above the threshold to the ...

K. L. F. Bane T. Naito T. Okugi J. Urakawa

2000-01-01

208

Scale and construal: how larger measurement units shrink length estimates and expand mental horizons.  

PubMed

Scale can vary by requiring a different number of units to measure the same target. But what are the consequences of using fewer, larger units? We draw on past psychophysical research that shows how using fewer units reduces clutter in measurement, translating to shorter length estimates. Additionally, we propose that larger scale is associated with targets further from a person's immediate experience (i.e., psychologically distant) and higher order mental representation. Evidence from Study 1 indicates that framing a target as further away causes it to be estimated as shorter because people use larger units to measure it compared to when the same target is framed as nearby. Two subsequent studies suggest that direct manipulation of larger (versus smaller) measurement scale produces not only shorter length estimates, but also more distal timing judgments (Study 2) and abstract mental representation (Study 3). Implications for scale and level of mental construal are discussed. PMID:21327357

Maglio, Sam J; Trope, Yaacov

2011-02-01

209

High-frequency noise measurements on MOSFETs with channel-lengths in sub-100 nm regime  

Microsoft Academic Search

High-Frequency signal and noise measurements on 40 nm, 80 nm, and 110 nm, gate-length MOS transistors are performed. On-wafer measurements of S-parameters up to 18 GHz yield an accurate small-signal RF device model with gm in excess of 1000 mS\\/mm. Noise contributions due to gate resistance, substrate resistance, source and drain resistances, substrate current and induced-gate noise are found to

Pradeep R. Patalay; R. P. Jindal; Hisashi Shichijo; S. Martin; Fan-Chi Hou; Django Trombley

2009-01-01

210

Low coherence tandem interferometry for the measurement of differential length sensing at two widely separated locations  

NASA Astrophysics Data System (ADS)

An all optical fibre based sensing configuration designed to measure the changes in differential length of two independent Fabry-Perot cavities at widely separated locations in an environment where strong temperature gradients may exist is demonstrated. Two Fabry-Perot sensing cavities are formed between the cleaved end of a fibre and a reflective surface. The presented technique is based on low coherence tandem interferometry incorporating high coherence interferometry as a calibration measurement.

Smith, Martin D.; MacPherson, William N.; Maier, Robert R. J.

2013-09-01

211

Selection of optimum frequencies for atmospheric electric path length measurement by satellite-borne microwave radiometers  

NASA Technical Reports Server (NTRS)

Numerical experiments using regressions by leaps and bounds have been performed to determine the optimum frequencies for satellite-borne microwave radiometers to estimate atmospheric electrical path length over the sea. The frequency range 5-40 GHz was searched. The effect of surface wind speed, sea surface temperature, and clouds was considered in the optimum frequency selection. The analysis indicates that approximately 0.6-cm rms accuracy is possible for one-way path length measurement using a proper pair of frequencies. The best two-channel subset selected by the leaps and bounds techniques is (16.0, 21.0) GHz.

Pandey, P. C.; Kakar, R. K.

1983-01-01

212

Pulsed ion beam measurement of defect diffusion lengths in irradiated solids.  

PubMed

Radiation-generated point defects in solids often experience dynamic annealing-diffusion and interaction processes after the thermalization of collision cascades. The length scale of dynamic annealing can be described in terms of the characteristic defect diffusion length (Ld). Here, we propose to measure Ld by a pulsed beam method. Our approach is based on the observation of enhanced defect production when, for individual ion pulses, the average separation between adjacent damage regions is smaller than Ld. We obtain a value for Ld of ~30 nm for float-zone Si crystals bombarded at room temperature with 500 keV Ar ions. PMID:23524408

Charnvanichborikarn, S; Myers, M T; Shao, L; Kucheyev, S O

2013-04-24

213

Amplified quenching of conjugated polymer nanoparticle photoluminescence for robust measurement of exciton diffusion length  

NASA Astrophysics Data System (ADS)

A new method for measuring exciton diffusion length in nanoparticles (NPs) of conjugated materials is presented. Cationic acceptor dyes are used to quench the photoluminescence in NPs of the prototypical conjugated polymer poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV). Amplified quenching of MEH-PPV emission is observed with an initial Stern-Volmer constant in excess of 105 M-1. Stern-Volmer plots are nonlinear with two distinct quenching regimes, hinting saturation of NP surfaces with acceptor molecules at some point during titration experiments. Using an assumption that highly efficient quenching of excitons occurs after saturation with acceptors at the NP surfaces, the amount of maximum emission quenching can be compared with a model of exciton diffusion to determine exciton diffusion length. By assuming quenching efficiency above 80%, the measured three dimensional exciton diffusion length is estimated to be 12 +/- 1 nm. This result is in the lower region of reported values ranging from 10 to 25 nm in MEH-PPV thin films. Both the derived model and the experimental methodology allow robust measurement of exciton diffusion length for any luminescent conjugated material from which NPs can be prepared.

Bjorgaard, Josiah A.; Köse, Muhammet E.

2013-05-01

214

Infrared Spectroscope for Electron Bunch-length Measurement: Heat Sensor Parameters Analysis  

SciTech Connect

The Linac Coherent Light Source (LCLS) is used for many experiments. Taking advantage of the free electron laser (FEL) process, scientists of various fields perform experiments of all kind. Some for example study protein folding; other experiments are more interested in the way electrons interact with the molecules before they are destroyed. These experiments among many others have very little information about the electrons x-ray produced by the FEL, except that the FEL is using bunches less than 10 femtoseconds long. To be able to interpret the data collected from those experiments, more accurate information is needed about the electron's bunch-length. Existing bunch length measurement techniques are not suitable for the measurement of such small time scales. Hence the need to design a device that will provide more precise information about the electron bunch length. This paper investigates the use of a pyreoelectric heat sensor that has a sensitivity of about 1.34 micro amps per watt for the single cell detector. Such sensitivity, added to the fact that the detector is an array sensor, makes the detector studied the primary candidate to be integrated to an infrared spectrometer designed to better measure the LCLS electron bunch length.

Domgmo-Momo, Gilles; /Towson U. /SLAC

2012-09-05

215

Measurements of ultrashort x-ray pulses by photon correlation  

Microsoft Academic Search

We propose single photon counting and photon correlation measurements to characterize ultrashort x-ray pulses, in particular to measure their coherence, spectral, and temporal characteristics. Photon coincidence measuremens allow us to measure higher order correlation between photons, from which temporal profiles of the pulses can be recovered.

Ferenc Raksi; Zsolt Papp

1995-01-01

216

Correlating DSC and X-Ray Measurements Of Crystallinity  

NASA Technical Reports Server (NTRS)

Experiment demonstrated approximate linear correlation between degree of crystallinity of multiphase polymer (as calculated from x-ray diffraction measurements) and heat of fusion of polymer (as calculated from differential scanning calorimetry (DSC) measurements). Correlation basis of simple new technique for estimating degree of crystallinity of specimens of polymer from DSC measurements alone.

Yen, Shiao-Ping S.; Lowry, Lynn E.; Bankston, Clyde P.

1991-01-01

217

Microlenses focal length measurement using Z-scan and parallel moiré deflectometry  

NASA Astrophysics Data System (ADS)

In this paper, a simple and accurate method based on Z-scan and parallel moiré deflectometry for measuring the focal length of microlenses is reported. A laser beam is focused by one lens and is re-collimated by another lens, and then strikes a parallel moiré deflectometer. In the presence of a microlens near the focal point of the first lens, the radius of curvature of the beam is changed; the parallel moiré fringes are formed only due to the beam divergence or convergence. The focal length of the microlens is obtained from the moiré fringe period graph without the need to know the position of the principal planes. This method is simple, more reliable, and completely automated. The implementation of the method is straightforward. Since a focused laser beam and Z-scan in free space are used, it can be employed for determining small focal lengths of small size microlenses without serious limitation on their size.

Rasouli, Saifollah; Rajabi, Y.; Sarabi, H.

2013-12-01

218

Vascular measurements correlate with estrogen receptor status  

PubMed Central

Background Breast carcinoma can be classified as either Estrogen Receptor (ER) positive or negative by immunohistochemical phenotyping, although ER expression may vary from 1 to 100% of malignant cells within an ER?+?tumor. This is similar to genetic variability observed in other tumor types and is generally viewed as a consequence of intratumoral evolution driven by random genetic mutations. Here we view cellular evolution within tumors as a classical Darwinian system in which variations in molecular properties represent predictable adaptations to spatially heterogeneous environmental selection forces. We hypothesize that ER expression is a successful adaptive strategy only if estrogen is present in the microenvironment. Since the dominant source of estrogen is blood flow, we hypothesized that, in general, intratumoral regions with higher blood flow would contain larger numbers of ER?+?cells when compared to areas of low blood flow and in turn necrosis. Methods This study used digital pathology whole slide image acquisition and advanced image analysis algorithms. We examined the spatial distribution of ER?+?and ER- cells, vascular density, vessel area, and tissue necrosis within histological sections of 24 breast cancer specimens. These data were correlated with the patients ER status and molecular pathology report findings. Results ANOVA analyses revealed a strong correlation between vascular area and ER expression and between high fractional necrosis and absent ER expression (R2?=?39%; p?correlate with tumor grade or size. Conclusion We conclude that ER expression can be understood as a Darwinian process and linked to variations in estrogen delivery by temporal and spatial heterogeneity in blood flow. This correlation suggests strategies to promote intratumoral blood flow or a cyclic introduction of estrogen in the treatment schedule could be explored as a counter-intuitive approach to increase the efficacy of anti-estrogen drugs.

2014-01-01

219

Probing the role of chain length on the diffusion dynamics of ?-conjugated polymers by fluorescence correlation spectroscopy.  

PubMed

We investigate the role of the chain length and molecular weight distribution on the diffusion dynamics of freshly synthesized MEH-PPV polymer chains. For the above purpose, a new technique based on combination of size exclusion chromatography (SEC) with fluorescence correlation spectroscopy (FCS) is developed to probe the diffusion dynamics of a narrow molecular weight distribution of fractionated samples of 20-500 kDa. The narrow dispersed samples were characterized by absorbance, emission, and time-resolved fluorescence decay techniques. The results revealed that the properties of fractionated samples were almost uniform for a wide range of molecular weights. A maximum entropy based method for FCS data analysis is employed to obtain the correct diffusion coefficients of the polymer chains with heterogeneous dynamics. The FCS experiment on the unfractionated broad molecular weight sample is not enough to establish the correlation between the molecular weight of the chains with diffusion dynamics and emphasized the need for relatively monodispersed ?-conjugated polymers. FCS results show that higher molecular weight chains diffuse much faster than shorter ones. Atomic force microscopy revealed that 300 kDa polymers produced 130 nm particles, whereas 50 kDa polymer chains formed micrometer size aggregates. At higher molecular weights, the strong chain interactions promote the formation of globular (or tightly packed) particles which diffuse faster in solution. The low molecular weight chains experience strong interparticle interaction; as a consequence, the diffusion of chains becomes slower. In the present investigation, we demonstrate the need for the narrow polydisperse sample for establishing the correlation between diffusion dynamics and chain length (or molecular weights) of ?-conjugated polymers using a single molecule spectroscopy technique such as FCS. PMID:21842892

Murthy, A V R; Goel, Mahima; Patil, Shivprasad; Jayakannan, M

2011-09-22

220

Correlative studies of satellite ozone sensor measurements  

NASA Astrophysics Data System (ADS)

Comparisons are made between total ozone measurements made by four satellite ozone sensors (TOMS, SBUV, TOVS and MFR). The comparisons were made during July 1979 when all sensors were operating simultaneously. The TOMS and SBUV sensors were observed to measure less total ozone than the MFR sensor, 10 and 15 Dobson units (DU) respectively. The MFR and TOMS sensors measured less ozone than the TOVS sensor, 19 and 28 DU, respectively. Latitudinal variability of the total ozone comparisons is discussed.

Lovill, J. E.; Ellis, J. S.

1983-06-01

221

A new triple correlation technique for measuring ultrashort laser pulses  

Microsoft Academic Search

A new triple correlation technique for measuring the complete intensity profile of ultrashort optical pulses is described. The triple correlation preserves the phase information of the input pulse so that a reconstruction of the triply correlated signal will provide a unique reconstruction of the input. The new technique described here uses two second-order, nonlinear optical interactions for the generation of

Nicholas G. Paulter; Arun K. Majumdar

1991-01-01

222

Reliability-guided digital image correlation for image deformation measurement  

Microsoft Academic Search

A universally applicable reliability-guided digital image correlation (DIC) method is proposed for reliable image deformation measurement. The zero-mean normalized cross correlation (ZNCC) coefficient is used to identify the reliability of the point computed. The correlation calculation begins with a seed point and is then guided by the ZNCC coefficient. That means the neighbors of the point with the highest ZNCC

Bing Pan

2009-01-01

223

The Comparison Of Accuracy Of Length Measurement Obtained From Terrestrial Laser Scanner And Total Station  

NASA Astrophysics Data System (ADS)

Nowadays the developments in the technologies are contributed to accuracy and reliability of terrestrial laser Scanning Technology. Therefore, Terrestrial laser scanners (TLS) are used in many engineering applications. The working principle of Terrestrial laser scanners is similar to reflectorless total stations. Terrestrial laser scanner is a device that can quickly measure the 3-dimensional point cloud of an image that is scanned in the form of x, y, z points. With the help of these operations, the realistic 3D models of scanned objects are generated. Terrestrial laser scanners have also significant advantages that distinguish them from traditional measurement methods. The accuracy and reliability of final products of TLS depends on accuracy and resolution of data obtained from laser scanner. The scientific research studies are carried out focusing on accuracy and sensitivity. Studies in this paper were made in Calibration Baseline (20-meter) and EDM Baseline (300 -meter) in the department of Geomatic Engineering, at the Yildiz Technical University. Purpose of this study is to determine the accuracy and sensitivity of length measuring of Optech ILRIS 3D Terrestrial Laser Scanner and Total station. Tests were carried out with specially prepared targets and in environments where they included the environmental and laboratory impacts. In this paper, geometric and nominal measurements of 3-dimensional (3D) models or point coordinate gathered by scanning object surfaces and targets using TLS were compared to the measurements of Total Stations (1+2ppm). In particular, the effects of the accuracy and sensitivity of the measuring length of the targets were determined. This reference targets shifted at varying intervals from the center of the scan point. TLS measurements were made between reference points and the starting point. The point clouds obtained by scanning created surface models. The differences in these movement directions of created surface models have identifying the movement of the reference object. The Tests determining the accuracy of length measurement of Optech ILRIS 3D Terrestrial Laser Scanner and Total Station are discussed.

Gumus, Kutalmis; Erkaya, Halil

2013-04-01

224

Optical microscopy measurement of pair correlation functions  

NASA Astrophysics Data System (ADS)

We studied the pair correlation function g(r) of silica particles with a fluorescent core and a nonfluorescent shell which were confined between two glass plates by optical video microscopy. To investigate the possible role of optical artifacts due to overlapping particle images, we compared experiments, where, first, the whole particle (white image) and then, only the fluorescent core (fluorescent image) was used for determining particle positions. While under white-image conditions the observed g(r) exhibits a main peak at about 1.2 times the particle’s diameter; under fluorescent image conditions the obtained g(r) resembles a short-ranged repulsive system where the main peak is close to contact. This discrepancy points towards artifacts of video microscopy, leading to erroneous g(r) and in turn to erroneous effective-pair potentials.

Ramírez-Saito, Angeles; Bechinger, Clemens; Arauz-Lara, José Luis

2006-09-01

225

Diffusion length measurements of thin GaAs solar cells by means of energetic electrons  

NASA Technical Reports Server (NTRS)

A calculation of the short circuit current density (j sub sc) of a thin GaAs solar cell induced by fast electrons is presented. It is shown that in spite of the disparity in thickness between the N-type portion of the junction and the P-type portion of the junction, the measurement of the bulk diffusion length L sub p of the N-type part of the junction is seriously hampered due to the presence of a sizable contribution to the j sub sc from the P-type region of the junction. Corrections of up to 50% had to be made in order to interpret the data correctly. Since these corrections were not amenable to direct measurements it is concluded that the electron beam method for the determination of the bulk minority carrier diffusion length, which works so well for Si solar cells, is a poor method when applied to thin GaAs cells.

Vonross, O.

1980-01-01

226

Scanning laser image correlation for measurement of flow.  

PubMed

Scanning laser image correlation (SLIC) is an optical correlation technique for measuring the fluid velocity of particles suspended in a liquid. This technique combines laser scanning of an arbitrary pattern with pair cross-correlation between any two points in the pattern. SLIC overcomes many of the limitations of other optical correlation techniques for flow measurement, such as laser speckle, spatial temporal image correlation spectroscopy, and two-foci methods. One of the main advantages of SLIC is that the concept can be applied to measurements on a range of scales through simple zooming or modifications in the instrumentation. Additionally, SLIC is relatively insensitive to instrument noise through the use of correlation analysis and is insensitive to background. SLIC can provide detailed information about the direction and pattern of flow. SLIC has potential applications ranging from microfluidics to blood flow measurements. PMID:20459248

Rossow, Molly J; Mantulin, William W; Gratton, Enrico

2010-01-01

227

Electron Bunch Length Measurements in the E-167 Plasma Wakefield Experiment  

SciTech Connect

Bunch length is of prime importance to beam driven plasma wakefield acceleration experiments due to its inverse relationship to the amplitude of the accelerating wake. We present here a summary of work done by the E167 collaboration measuring the SLAC ultra-short bunches via autocorrelation of coherent transition radiation. We have studied material transmission properties and improved our autocorrelation traces using materials with better spectral characteristics.

Blumenfeld, Ian; Berry, Melissa; Decker, Franz-Josef; Hogan, Mark J.; Ischebeck, Rasmus; Iverson, Richard; Kirby, Neil; Siemann, Robert H.; Walz, Dieter; Zacherl, Walter [Stanford Linear Accelerator Center, 2575 Sand Hill Road, Menlo Park, CA 94025 (United States); Auerbach, David; Clayton, Christopher E.; Huang, Chengkun; Johnson, Devon; Joshi, Chandrashekhar; Lu, Wei; Marsh, Kenneth A.; Mori, Warren B.; Zhou, Miaomiao [University of California at Los Angeles, 405 Hilgard Avenue, Los Angeles, CA 90095 (United States); Katsouleas, Thomas [University of Southern California, University Park Campus, Los Angeles, CA 90089 (United States)] (and others)

2006-11-27

228

Path length modulation technique for scatter noise immunity in squeezing measurements.  

PubMed

We present a technique for frequency shifting scattering induced noise on squeezed light beams, providing immunity from scattered light while preserving the squeezed states. Using a 500 Hz pre and postsqueezing apparatus path length modulation, we show up to a 20 dB reduction in scattering induced noise while recovering squeezing measurement below the shot noise level. Such a technique offers immunity to spurious scattering sources without the need for optically lossy isolation optics. PMID:23811897

Wade, Andrew R; Chua, Sheon S Y; Stefszky, Michael S; Shaddock, Daniel A; McClelland, David E

2013-07-01

229

Contingent Use of Fetal Fibronectin Testing and Cervical Length Measurement in Women With Preterm Labour  

Microsoft Academic Search

Objective: To evaluate the contingent use of fetal fibronectin (fFN) testing and cervical length (CL) measurement to predict preterm delivery, and to validate the use of phosphorylated IGFBP-1 as a predictor of preterm delivery. Methods: We recruited 71 women with a clinical diagnosis of preterm labour between 24 and 34 weeks, and tested for the presence of fFN and IGFBP-1

François Audibert; Suzanne Fortin; Edgard Delvin; Anissa Djemli; Suzanne Brunet; Johanne Dubé; William D. Fraser

2010-01-01

230

Electron Bunch Length Measurements in the E-167 Plasma Wakefield Experiment  

SciTech Connect

Bunch length is of prime importance to beam driven plasma wakefield acceleration experiments due to its inverse relationship to the amplitude of the accelerating wake. We present here a summary of work done by the E167 collaboration measuring the SLAC ultra-short bunches via autocorrelation of coherent transition radiation. We have studied material transmission properties and improved our autocorrelation traces using materials with better spectral characteristics.

Blumenfeld, I.; Auerbach, D.; Berry, M.; Clayton, C.E.; Decker, F.J.; Hogan, M.J.; Huang, Cheng-Kun; Ischebeck, R.; Iverson, R.; Johnson, D.; Joshi, C.; Katsouleas, T.; Kirby, N.; Lu, Wei; Marsh, K.A.; Mori, W.B.; Muggli, P.; Oz, E.; Siemann, R.H.; Walz, D.; Zacherl, W.; /SLAC /UCLA /Southern California U.

2007-03-27

231

Measurement of atmospheric coherence length with differential movement of the image sensor  

NASA Astrophysics Data System (ADS)

This paper gives the introduction about a new measuring device which is to measure th e atmospheric coherence length by using the differential movement principle.The system can observe the edge of the sun in the day time, and also observe planets at night. This system can measure the atmospheric coherence length in both horizontal and slant directions. The measurement in the day time requests the assistance of the attenuator and beacon beam of the atmospheric coherence length in the direction of the slant path.The working principle is the laser beam scattered by atmospheric turbulence through into the receiving optical system. Because the receiving system which is consists of two completely symmetrical telephoto optical system. Therefore?two optical channels in turbulence device are completely identical. After passing through the optical channels, the beam focusing is finished. By adjusting the optical system manually or automatically, two light point images can be formed on the photosensitive element of the CCD. Atmospheric turbulence can cause phase fluctuation of wave front. After aggregation by the receiving lens, The photosensitive element of CCD can collect the relative jitter of the two imaging optical centroid positions we require, and researchers can obtain relative changes from the two centroid positions by the calculations of computer software, as the result, the atmospheric coherence length is obtained. By means of the simulation of the optical system and the imaging quality optimization by Code V, researchers can rather achieve transfer function diagram, the circle of confusion value in different views and energy distribution. From above, researchers can examine whether the optical system is being qualified, or the method is leading to a better observation effect. At end of this dissertation, the limitations of this system will be analyzed, and the improvement methods and suggestions will be provided.

Jia, Yu-gang; Tong, Shou-feng

2013-08-01

232

Measurement of the coherence length of diffusely scattered laser beams with adaptive photodetectors  

NASA Astrophysics Data System (ADS)

Original experiments on measurements of the coherence length of diffusely scattered CW laser beams using GaAs adaptive photodetectors based on the photo-EMF effect are presented. Simplicity of the configuration, capability to detect aberrated speckle-like wavefronts with high signal-to-noise ratio, and potentially high speed of operation make this configuration potentially useful for Optical Coherence Tomography and Laser Ranging.

Carrasco, M. L. Arroyo; Montero, P. Rodr?´guez; Stepanov, S.

1998-12-01

233

Ultrasonic measurement of stress in railroad wheels and in long lengths of welded rail  

NASA Technical Reports Server (NTRS)

The failure of high speed emergency braking is discussed for railroad wheels and track. It is shown that high compressive residual stresses exist in the rims of new wheels which generate excessive heat, reducing the stress levels. Thermal stresses that build up in continuous lengths of welded track are reported and nondestructive methods of measuring stresses in thick steel are presented for identification, replacement, or adjustment before hazardous failures occur.

Clotfelter, W. N.; Risch, E. R.

1974-01-01

234

d + Au hadron correlation measurements at PHENIX  

NASA Astrophysics Data System (ADS)

In these proceedings, we discuss recent results from d + Au collisions in PHENIX ridge related measurements and their possible hydrodynamic origin. We present the v2 at midrapidity and measurements of the pseudorapidity dependence of the ridge, distinguishing between the d-going and Au-going directions. We investigate the possible geometrical origin by comparing v2 in d + Au to that in p + Pb, Au + Au and Pb + Pb collisions. Future plans to clarify the role of geometry in small collision systems at RHIC are discussed.

Sickles, Anne M.

2014-06-01

235

Measuring correlations between non-stationary series with DCCA coefficient  

NASA Astrophysics Data System (ADS)

In this short report, we investigate the ability of the DCCA coefficient to measure correlation level between non-stationary series. Based on a wide Monte Carlo simulation study, we show that the DCCA coefficient can estimate the correlation coefficient accurately regardless the strength of non-stationarity (measured by the fractional differencing parameter d). For a comparison, we also report the results for the standard Pearson correlation coefficient. The DCCA coefficient dominates the Pearson coefficient for non-stationary series.

Kristoufek, Ladislav

2014-05-01

236

Measurements of electric charge and screening length of microparticles in a plasma sheath  

SciTech Connect

An experiment is described in which microparticles are levitated within a rf sheath above a conducting plate in argon plasma. The microparticles forming a two-dimensional crystal structure are considered to possess Debye screening Coulomb potential {phi}(r)=(Q/4{pi}{epsilon}{sub 0}r)exp(-r/{lambda}), where Q is the electric charge, r is distance, and {lambda} is the screening length. When the crystal structure is slanted with an angle {theta}, a particle experiences a force Mg sin {theta}, where M is the mass of the particle and g is acceleration due to gravity, which must be equal to the Debye screened Coulomb force from other particles. By changing {theta}, relations for {lambda}(Q) are measured. The screening length {lambda} and Q are determined uniquely from the crossing points of several relations. The electric charge Q is also estimated from a floating potential measured with a probe. The measured {lambda} is nearly equal to an ion Debye length.

Nakamura, Y.; Ishihara, O. [Department of Physics, Faculty of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501 (Japan)

2009-04-15

237

New measurements of the coherent and incoherent neutron scattering lengths of 13C  

SciTech Connect

The techniques of neutron interferometry and neutron diffraction were used to determine the coherent and incoherent neutron scattering lengths of 13C. From a neutron interferometry measurement of the optical path difference in liquid samples: 13CS2 versus natCS2, we obtain a bound coherent scattering length of bcoh,13C = 6.502 0.003 fm which differs appreciably from the standard tabulated value of 6.19 0.09 fm. The resulting contrast of only 0.146(3) fm with respect to bcoh,natC = 6.6484 0.0013 fm has consequences for neutron diffraction experiments involving 13C isotopic substitution. Combining our result for bcoh,13C with precise neutron diffraction measurements of the self-scattering intensities of liquid samples: 13CS2 versus natCS2, and 13CO2 versus 12CO2, we deduce a bound incoherent scattering length of bincoh,13C = ?0.73 0.14 fm that is consistent with the standard tabulated value of ?0.52 0.09 fm. The results presented here have required accurate measurements of small effects, for which particular attention has been given to the data analysis.

Fischer, Henry E [Institut Laue-Langevin (ILL); Neuefeind, Joerg C [ORNL; Simonson, J Michael {Mike} [ORNL; Loidl, Rudolf [Institut Laue-Langevin (ILL); Rauch, Helmut [E141 Atominstitut der Österreichischen Universitäten,

2008-01-01

238

Turbulence spectra and length scales measured in film coolant flows emerging from discrete holes  

SciTech Connect

To date, very little attention has been devoted to the scales and turbulence energy spectra of coolant exiting from film cooling holes. Length-scale documentation and spectral measurements have primarily been concerned with the free-stream flow with which the coolant interacts. Documentation of scales and energy decomposition of the coolant flow leads to more complete understanding of this important flow and the mechanisms by which it disperses and mixes with the free stream. CFD modeling of the emerging flow can use these data as verification that flow computations are accurate. To address this need, spectral measurements were taken with single-sensor, hot-wire anemometry at the exit plane of film cooling holes. Energy spectral distributions and length scales calculated from these distributions are presented for film cooling holes of different lengths and for coolant supply plenums of different geometries. Measurements are presented on the hole streamwise centerline at the center of the hole, one-half diameter upstream of center, and one-half diameter downstream of center. The data highlight some fundamental differences in energy content, dominant frequencies, and scales with changes in the hole and plenum geometries. Coolant flowing through long holes exhibits smoothly distributed spectra as might be anticipated in fully developed tube flows. Spectra from short-hole flows, however, show dominant frequencies.

Burd, S.W. [Pratt and Whitney Florida, West Palm Beach, FL (United States). Combustor Module Center; Simon, T.W. [Univ. of Minnesota, Minneapolis, MN (United States). Heat Transfer Lab.

1999-07-01

239

Measurement of coherence length and incoherent source size of hard x-ray undulator beamline at Pohang Light Source-II.  

PubMed

We measured the spatial coherence length and incoherent source size of a hard x-ray undulator beamline at Pohang Light Source-II, the stored electron energy of which has been increased from 2.5 GeV to 3 GeV. The coherence length was determined by single-slit measurement of the visibility of the Fresnel diffraction pattern. The correlated incoherent source size was cross-checked for three different optics: the single slit, beryllium parabolic compound refractive lenses, and the Fresnel zone plate. We concluded that the undulator beamline has an effective incoherent source size (FWHM) of 540 ?m (horizontal) × 50 ?m (vertical). PMID:24784668

Park, So Yeong; Hong, Chung Ki; Lim, Jun

2014-04-01

240

Measurement of coherence length and incoherent source size of hard x-ray undulator beamline at Pohang Light Source-II  

NASA Astrophysics Data System (ADS)

We measured the spatial coherence length and incoherent source size of a hard x-ray undulator beamline at Pohang Light Source-II, the stored electron energy of which has been increased from 2.5 GeV to 3 GeV. The coherence length was determined by single-slit measurement of the visibility of the Fresnel diffraction pattern. The correlated incoherent source size was cross-checked for three different optics: the single slit, beryllium parabolic compound refractive lenses, and the Fresnel zone plate. We concluded that the undulator beamline has an effective incoherent source size (FWHM) of 540 ?m (horizontal) × 50 ?m (vertical).

Park, So Yeong; Hong, Chung Ki; Lim, Jun

2014-04-01

241

Internalized Heterosexism: Measurement, Psychosocial Correlates, and Research Directions  

ERIC Educational Resources Information Center

This article provides an integrated critical review of the literature on internalized heterosexism/internalized homophobia (IH), its measurement, and its psychosocial correlates. It describes the psychometric properties of six published measures used to operationalize the construct of IH. It also critically reviews empirical studies on correlates

Szymanski, Dawn M.; Kashubeck-West, Susan; Meyer, Jill

2008-01-01

242

Correlations among Three Measures of Congruence.  

ERIC Educational Resources Information Center

Combinations of Holland codes were drawn randomly and used to compare three common measures of congruency (the Iachan Index, the Kwak and Pulvino Index, and the Zener-Schnuelle Index) between pairs of three-letter codes. Findings suggest that the choice of which index is most appropriate remains contingent on one's particular purpose. (Author/NB)

Miller, Mark J.

1992-01-01

243

Measuring Microscopic Deformations with Digital Image Correlation  

Microsoft Academic Search

This paper describes a feasibility study of a high magnification full field deformation measurement system. The system consists of an image acquiring and analysis system and an optical metallurgical microscope. It can be used to determine in-plane surface deformations at magnifications up to 2000 pixels\\/mm. Images from an optical microscope are acquired by using a CCD camera and a digitizing

Zili Sun; Jed S Lyons; Stephen R McNeill

1997-01-01

244

Thermal Diffusivity and Conductivity Measurements: Effect of Sample Length and Radiation  

NASA Astrophysics Data System (ADS)

Measurements of thermal diffusivity D and conductivity ? commonly show an upturn as a function of temperature. The upturn is very apparent in semi-transparent materials such as upper mantle minerals at absolute temperatures T of the order of 600-700 K. Although the effect is readily attributed to a radiative component, it shows a temperature dependence that is more characteristic of a black body (e.g., T3) than that expected from actual optical absorption spectra at high temperature for very large dimensions. When radiative conductivity ?r is obtained from optical methods, it tends begin at lower temperatures and to level off as absorption increases with T. Part of the discrepancy can be assigned to the fact that photon mean free path mfp( T) is usually comparable with sample dimensions. However, the problem is worsened in portions of the spectra by spectral path lengths (reciprocal absorption coefficients) substantially longer than sample lengths, an effect manifested in length-dependent radiative diffusion. For olivine (Mg0.91,Fe0.09)2SiO4 we have used a model of 1-dimensional spectral absorption and emission between volume elements to demonstrate that as sample length increases, ?r approaches that expected from spectral methods.

Shankland, T. J.; Schilling, F. R.; Gibert, B.; Gratz, K.

2005-12-01

245

Normal values for renal length and volume as measured by magnetic resonance imaging.  

PubMed

The objective of this magnetic resonance imaging (MRI) study was to (1) test the validity of the ellipsoid formula for estimating kidney volume using ex vivo and in vivo models and (2) establish a normal range of values for kidney length and volume in patients with no known history of renal disease. The volumes of five excised porcine kidneys were measured by (1) disc-summation method, (2) ellipsoid formula, and (3) water displacement method. In a retrospective, consecutive group of clinically referred patients (n = 150; 300 kidneys), individual kidney volume and length were calculated by the disc-summation method and by multiplanar reformation of MRI data, respectively. For comparison, kidney volumes also were calculated using the ellipsoid formula in all patients. Renal volume that was obtained by MRI using the disc-summation method was within 5% of the volume that was determined by the water displacement method, independent of the spatial resolution of the MRI technique used. Data from both the in vivo and the ex vivo models revealed that the ellipsoid formula that commonly is used in ultrasonography underestimates renal volume by 17 to 29% compared with the disc-summation method (P < 0.05). As measured by MRI (mean +/- SD), kidney lengths were 12.4 +/- 0.9 cm for men and 11.6 +/- 1.1 cm for women, and kidney volumes were 202 +/- 36 ml for men and 154 +/- 33 ml for women. The results from the ex vivo MRI study show that the kidney volume that was obtained using the disc-summation method is within 5% of the true kidney volume as measured by the water displacement method. The ellipsoid formula consistently and significantly underestimates the true kidney volume. The length and the volume of kidneys that are obtained by MRI in patients with no known history of intrinsic renal disease are greater than the commonly quoted reference values that are obtained by ultrasonography. PMID:17699385

Cheong, Benjamin; Muthupillai, Raja; Rubin, Mario F; Flamm, Scott D

2007-01-01

246

Scattering length measurements from radiative pion capture and neutron-deuteron breakup  

SciTech Connect

The neutron-neutron and neutron-proton {sup 1}S{sub 0} scattering lengths a{sub nn} and a{sub np}, respectively, were determined simultaneously from the neutron-deuteron breakup reaction. Their comparison with the recommended values obtained from two body reactions gives a measure of the importance of three-nucleon force effects in the three-nucleon continuum. In order to check on the result obtained for a{sub nn} from the two-body {pi}{sup {minus}}-d capture reaction, a new measurement was performed at LANL. Preliminary results of the three experiments are given.

Gibson, B.F. [Los Alamos National Lab., NM (United States); Tornow, W. [Duke Univ., Durham, NC (United States). Dept. of Physics]|[Triangle Universities Nuclear Lab., Durham, NC (United States); Carman, T.S. [Lawrence Livermore National Lab., CA (United States)] [and others

1997-07-01

247

Comparison of PACS and Hard-copy 51-inch Radiographs for Measuring Leg Length and Deformity  

Microsoft Academic Search

Background  The picture archiving and communication system (PACS) eventually will replace the use of standard hard-copy radiographs. It\\u000a is unknown whether measurements of limb length discrepancy (LLD) and deformity on PACS compare in accuracy and reproducibility\\u000a with those from hard-copy radiographs.\\u000a \\u000a \\u000a \\u000a \\u000a Questions\\/purposes  We compared the reproducibility and reliability of LLD and deformity measurements for each of these two media.\\u000a \\u000a \\u000a \\u000a Methods  We retrospectively reviewed

Saurabh Khakharia; Daniel Bigman; Austin T. Fragomen; Helene Pavlov; S. Robert Rozbruch

2011-01-01

248

Motor evoked potential response latencies demonstrate moderate correlations with height and limb length in healthy young adults.  

PubMed

The purposes of this study were to determine 1) if motor evoked potential (MEP) response latencies and central motor conduction time (CMCT) are significantly correlated with lower extremity (LE) length or height, and 2) determine if MEP response latencies and CMCT are different between sexes among healthy adults. A cross-sectional, descriptive laboratory design was used. MEPs were recorded from 106 subjects (60 females, 46 males; age 20.1 +/- 2.4 years) by applying transcranial magnetic stimulation over the primary motor cortex. MEP response latencies were recorded using electromyography (EMG) responses from the tibialis anterior; CMCT was calculated from cortical and spinal-evoked MEP latencies. MEP latencies were significantly different between males (29.53 +/- 3.02 msec) and females (27.69 +/- 2.81 msec). Height accounted for greater variability (eta2 = .369 or approximately 37%) between genders and demonstrated a good-to-moderate correlation with MEP latency (r = .595, p = < .0001). Accounting for height as a confounding variable in the analyses, no significant differences between genders was observed (F1,103 = 2.45, p = .21). MEP latency should be adjusted to each subjects' height to account for the unwanted variability associated with the varied heights of subjects being tested, thereby permitting an accurate comparison and meaningful interpretation of MEPs between subjects or patients. PMID:23682541

Livingston, Scott C; Friedlander, Daniel L; Gibson, Brent C; Melvin, James R

2013-03-01

249

Quantum correlations in position, momentum and intermediate bases, measured using fiber arrays  

NASA Astrophysics Data System (ADS)

We have developed a new approach to measuring the spatial position of a single photon. Using fibers of different length, all connected to a single detector allows us to use the high timing precision of single photon avalanche diodes (SPAD) to spatially locate the photon. We have built two 8-element detector arrays to measure the full-field quantum correlations in position, momentum and intermediate bases for photon pairs produced in parametric down conversion. The strength of the position-momentum correlations is found to be an order of magnitude below the classical limit.

Izdebski, F.; Leach, J.; Warburton, R. E.; Ireland, D. G.; Barnett, S. M.; Yao, A. M.; Buller, G. S.; Padgett, M. J.

2012-02-01

250

Atomic force microscopy of reovirus dsRNA: a routine technique for length measurements.  

PubMed Central

Atomic force microscopy (AFM) was used to image reovirus double stranded RNA (dsRNA) deposited from diluted buffer solution onto a chemically treated mica surface. This procedure allows AFM images of dsRNA molecules to be obtained with a quality close to that obtained with conventional electron microscopy. The length of the molecules were measured directly on a computer display using the digitally acquired images. The lengths of the molecules varied between 0.2 and 1.8 microns. Statistical analysis showed a multimodal distribution with clear maxima at 0.4, 0.65 and 1.05 microns. These data are in a good agreement with those obtained by electron microscopy and gel electrophoresis. Images

Lyubchenko, Y L; Jacobs, B L; Lindsay, S M

1992-01-01

251

Bunch Length Measurements at the ATF Damping Ring in April 2000  

SciTech Connect

We want to accurately know the energy spread and bunch length dependence on current in the ATF damping ring. One reason is to know the strength of the impedance: From the energy spread measurements we know whether or not we are above the threshold to the microwave instability, and from the energy spread and bunch length measurements we find out the extent of potential-well bunch lengthening (PWBL). Another reason for these measurements is to help in our understanding of the intra-beam scattering (IBS) effect in the ATF. The ATF as it is now, running below design energy and with the wigglers turned off, is strongly affected by IBS. To check for consistency with IBS theory of, for example, the measured vertical beam size, we need to know all dimensions of the beam, including the longitudinal one. But beyond this practical reason for studying IBS, IBS is currently a hot research topic at many accelerators around the world (see e.g. Ref. [1]), and the effect in actual machines is not well understood. Typically, when comparing theory with measurements fudge factors are needed to get agreement (see e.g. Ref. [1]). With its strong IBS effect, the ATF is an ideal machine for studying IBS, and an indispensable ingredient for this study is a knowledge of the longitudinal phase space of the beam. The results of earlier bunch lengthening measurements in the ATF can be found in Refs. [2]-[4]. Measurements of current dependent effects, especially bunch length measurements using a streak camera, can be difficult to perform accurately. For example, space charge in the camera itself can lead to systematic errors in the measurement results. It is important the results be accurate and reproducible. In the measurements of both December 1998[3] and December 1999[4], by using light filters, the authors first checked that space charge in the streak camera was not significant. And then the Dec 99 authors show that their results agree with those Dec 98, i.e. on the dates of the two measurements the results were reproducible. Since IBS is so strong in the ATF, in the Dec 99 measurements an attempt was made to estimate the impedance effect using the following method: First, from the form of the energy spread vs. current measurements it was concluded that the threshold to the microwave instability was beyond 2 mA. Then, by dividing the bunch length vs. current curve by the energy spread vs. current curve the effect of IBS was divided out, and PWBL was approximated. The assumption is that PWBL can be treated as a perturbation on top of IBS. The result was that this component of bunch lengthening was found to grow by 7-15% (depending on the rf voltage) between the currents of .5 mA and 2 mA, about a factor of 3 less than the total bunch length growth. The conclusion was that the inductive component of the impedance was small, in fact much smaller than had been concluded earlier in Ref. [2]. Electron machines generally run in a parameter regime where IBS is an insignificant effect, and impedance measurements and calculations have also normally been performed for machines where IBS is unimportant. To simplify the interpretation of the impedance from bunch length measurements, in April 2000 the energy spread and bunch length measurements of Dec 99 were repeated, but now with the beam on a linear (difference) coupling resonance, where the horizontal and vertical emittances were approximately equal. For this case the effect of IBS was expected to be very small. An energy spread vs. current measurement under such conditions will also allow us to more clearly see whether we reach the threshold to the microwave instability. As part of the April data taking we, in addition, repeated the earlier off-coupling measurements, in order to check the reproducibility of the earlier results. In this report we present and analyze this recent set of data, and compare it with the results of the earlier measurements, particularly those of Dec 99. The measurements and analysis of data in this report follow essentially the same procedure as was used in Ref. [4]. In the prese

Bane, K.L.F.; /SLAC; Naito, T.; Okugi, T.; Urakawa, J.; /KEK, Tsukuba

2005-12-19

252

Comparison of Echo 7 field line length measurements to magnetospheric model predictions  

NASA Technical Reports Server (NTRS)

The Echo 7 sounding rocket experiment injected electron beams on central tail field lines near L = 6.5. Numerous injections returned to the payload as 'conjugate echoes' after mirroring in the southern hemisphere. Field line lengths calculated from measured conjugate echo bounce times and energies are compared to predictions made by integrating electron trajectories through various magnetospheric models. Although Kp at launch was 3-, quiet time magnetic models best fit the echo measurements. Geosynchronous satellite magnetometer measurements near the Echo 7 field lines during the flight were best modeled by the Olson-Pfitzer Dynamic Model and the Tsyganenko-Usmanov model for Kp = 3. The discrepancy between the models that best fit the Echo 7 data and those that fit the satellite data was most likely due to uncertainties in the small-scale configuration of the magnetospheric models. The field line length measured by the conjugate echoes showed some temporal variation in the magnetic field, also indicated by the satellite magnetometers. This demonstrates the utility an Echo-style experiment could have in substorm studies.

Nemzek, R. J.; Malcolm, P. R.; Winckler, J. R.

1992-01-01

253

Electron-beam induced current measurements of diffusion length in Si doped MOCVD grown GaN  

Microsoft Academic Search

This paper reports on the electron-beam induced current (EBIC) measurement of minority carrier diffusion length as a function of electron beam acceleration voltage in Si-doped, MOCVD grown, gallium nitride. The measured diffusion length varied from 160nm at 8kV to 220nm at 15kV. Possible reasons for the observed diffusion length dependence on voltage are discussed.

D. Wee; G. Parish; B. D. Nener

2010-01-01

254

Measurement of growing dynamical length scale on approach to jamming in granular systems  

NASA Astrophysics Data System (ADS)

The flow of granular materials is of widespread practical and fundamental interest. One challenge to understanding and controlling behavior is that the response is nonlinear, with a forcing threshold below which the medium is static. Furthermore, just above threshold the response may be intermittent even though the forcing is steady. Two familiar examples are avalanches on a heap and clogging in a silo. Another example is dynamical heterogeneities for systems brought close to jamming, where intermediate-time motion is correlated in the form of intermitted string-like swirls. Here this will be illustrated with experiments on air-driven beads, where jamming is approached by lowering the effective temperature, as well as by experiments on rapid heap flow, where jamming is approached as a function of depth from the free surface. Use of novel statistical quantities and optical spectroscopies reveal a growing dynamical length scale on approach to jamming. Collaborators: Adam Abate, Hiroaki Katsuragi, Aaron Keys, Sharon Glotzer.

Durian, Douglas

2009-03-01

255

Femoral pinless length and offset measurements during computer-assisted, minimally invasive total hip arthroplasty.  

PubMed

We asked whether the intraoperative assessment of leg length (LL) and offset (OS) change would be accurate using a novel pinless femoral reference system during unilateral minimally invasive THA in 50 patients with a mean age of 60years (48-79). LL and OS change measured at surgery was compared with LL/OS change as measured on magnification-corrected preoperative and postoperative radiographs by two blinded examiners. The radiographic evaluation showed a high inter-rater reliability (r>0.80 for all assessments). The mean differences (±95% limits of agreement) between navigation and radiographic measurements on the treated side were +0.4mm (±3.6) for LL and -1.0mm (±3.9) for OS. Femoral pinless navigation technology represents a feasible assistance in THA. PMID:24269098

Renkawitz, Tobias; Sendtner, Ernst; Schuster, Tibor; Weber, Markus; Grifka, Joachim; Woerner, Michael

2014-05-01

256

Measurements of the effect of free-stream turbulence length scale on heat transfer  

NASA Astrophysics Data System (ADS)

The effects of free-stream turbulence scale on heat transfer through a turbulent flat plate boundary layer have been measured. A variety of turbulence spectra were produced by parallel bar grids. The design of these was guided by previous measurements of combustion chamber turbulence. Heat transfer was measured transiently using thin film gauges. The heat transfer to the plate was found to be a function of turbulence integral length scale as well as intensity, and is of relevance to gas turbine heat transfer where airfoils are subject to high turbulence levels from the combustor. Enhancement factors of up to 40 percent were experienced and the results extend conclusions drawn by other workers to higher turbulence levels and scales.

Moss, R. W.; Oldfield, M. L. G.

1992-06-01

257

Measurement of diffusion length, lifetime, and surface recombination velocity in thin semiconductor layers  

NASA Astrophysics Data System (ADS)

A small-signal admittance method is developed for the determination of two important parameters affecting the performance of several semiconductor devices with thin layers such as integrated-injection-logic and MOS transistors, OCHI-HLE, BSF and TJ solar cells. These parameters, the minority-carrier diffusion length (or the minority-carrier lifetime) and the surface recombination velocity, are found using a combination of low-frequency and high-frequency admittance measurements. The theoretical base of the method and experimental results showing its application and usefulness are presented.

Gonzalez, F. N.; Neugroschel, A.

1984-04-01

258

Measurement of the transverse spin correlation in Z ? ? + ? ? decays  

Microsoft Academic Search

The measurement of the correlation between the transverse spin components of ?+ ?? pairs collected during 1992 to 1994 with the DELPHI detector at LEPI is presented. A value C? = 0.87 ± 0.20 (stat.) ?0.12+0.10 (syst.) was obtained for the correlation parameter, in agreement with the Standard Model expectation.

P. Abreu; W. Adam; T. Adye; I. Ajinenko; G. D. Alekseev; R. Alemany; P. P. Allport; S. Almehed; Ugo Amaldi; S. Amato; P. Andersson; A. Andreazza; P. Antilogus; W. D. Apel; B. Åsman; J. E. Augustin; A. Augustinus; Paul Baillon; P. Bambade; F. Barao; M S Barbi; Dimitri Yuri Bardin; G. Barker; A. Baroncelli; O. Barring; M. J. Bates; Marco Battaglia; M. Baubillier; J. Baudot; K. H. Becks; M. Begalli; P. Beilliere; Yu A Belokopytov; K S Belous; Alberto C Benvenuti; M. Berggren; D. Bertini; D. Bertrand; M. Besancon; F. Bianchi; M. Bigi; M. S. Bilenky; P. Billoir; M. A. Bizouard; D. Bloch; M. Blume; M. Bonesini; W. Bonivento; P. S. L. Booth; A. W. Borgland; G. Borisov; C. Bosio; O. Botner; E. Boudinov; B. Bouquet; C. Bourdarios; T. J. V. Bowcock; I. Bozovic; M. Bozzo; P. Branchini; K. D. Brand; T. Brenke; R. A. Brenner; C. Bricman; R. C. A. Brown; P. Bruckman; J. M. Brunet; L. Bugge; T. Buran; T. Burgsmueller; P. Buschmann; S. Cabrera; M. Caccia; M. Calvi; A. J. Camacho Rozas; T. Camporesi; V. Canale; M. Canepa; F. Cao; F. Carena; L. Carroll; Carlo Caso; M. V. Castillo Gimenez; A. Cattai; F. R. Cavallo; V. Chabaud; Ph. Charpentier; L. Chaussard; P. Checchia; G. A. Chelkov; M. Chen; R. Chierici; P V Chliapnikov; P. Chochula; V. Chorowicz; V. Cindro; P. Collins; R. Contri; E. Cortina; G. Cosme; F. Cossutti; J. H. Cowell; H. B. Crawley; D J Crennell; G. Crosetti; J. Cuevas Maestro; S. Czellar; J. Dahm; B. Dalmagne; M. Dam; G. Damgaard; P. D. Dauncey; Martyn Davenport; W. Da Silva; A. Deghorain; G. Della Ricca; P A Delpierre; N. Demaria; A. De Angelis; Wim de Boer; S. De Brabandere; C. De Clercq; C. De La Vaissiere; B. De Lotto; A. De Min; L S De Paula; H. Dijkstra; Lucia Di Ciaccio; A. di Diodato; A. Djannati; J. Dolbeau; K. Doroba; M. Dracos; J. Drees; K.-A. Drees; M. Dris; J. D. Durand; D M Edsall; R. Ehret; G. Eigen; T J C Ekelöf; Gösta Ekspong; M. Elsing; J. P. Engel; B. Erzen; M. Espirito Santo; E. Falk; G K Fanourakis; D. Fassouliotis; Michael Feindt; P. Ferrari; A. Ferrer; S. Fichet; T. A. Filippas; A. Firestone; P.-A. Fischer; H. Foeth; E. Fokitis; F. Fontanelli; F. Formenti; B J Franek; A. G. Frodesen; R. Fruhwirth; F. Fulda-Quenzer; J A Fuster; A. Galloni; D. Gamba; M. Gandelman; C. Garcia; J. Garcia; C. Gaspar; U. Gasparini; Ph. Gavillet; E. N. Gazis; D. Gele; J. P. Gerber; R. Gokieli; B. Golob; P. Goncalves; Gian P Gopal; L. Gorn; M. Gorski; Yu. Gouz; Valerio Gracco; E. Graziani; C. Green; A. Grefrath; P. Gris; G. Grosdidier; K. Grzelak; S A Gumenyuk; M. Gunther; J. Guy; F. Hahn; S. Hahn; Z. Hajduk; A. Hallgren; K. Hamacher; F. J. Harris; V. Hedberg; R P Henriques; J. J. Hernandez; P. Herquet; H. Herr; T. L. Hessing; J.-M. Heuser; E. Higon; Hans Jürgen Hilke; S. O. Holmgren; P. J. Holt; D J Holthuizen; S. Hoorelbeke; M A Houlden; Josef Hrubec; K. Huet; K. Hultqvist; J. N. Jackson; R. Jacobsson; P. Jalocha; R. Janik; Ch. Jarlskog; G. Jarlskog; P. Jarry; B. Jean-Marie; E. K. Johansson; L B Jönsson; P E Jönsson; Christian Joram; P. Juillot; M. Kaiser; F. Kapusta; K. Karafasoulis; M. Karlsson; S. Katsanevas; E. C. Katsoufis; R. Keranen; Yu A Khokhlov; B. A. Khomenko; N N Khovanskii; B J King; N. J. Kjaer; O. Klapp; H. Klein; P M Kluit; D. Knoblauch; B. Koene; P. Kokkinias; A K Konoplyannikov; M. Koratzinos; K. Korcyl; V. Kostioukhine; C. Kourkoumelis; O. Kouznetsov; Manfred Krammer; C. Kreuter; I J Kronkvist; Z Krumshtein; W. Krupinski; P. Kubinec; W. Kucewicz; K L Kurvinen; C. Lacasta; I. Laktineh; J. W. Lamsa; L. Lanceri; P. Langefeld; J. P. Laugier; R. Lauhakangas; Gerhard Leder; F. Ledroit; V. Lefebure; C. K. Legan; A. Leisos; R. Leitner; J. Lemonne; Georg Lenzen; V. Lepeltier; T. Lesiak; J. Libby; D. Liko; R. Lindner; A. Lipniacka; I. Lippi; B. Loerstad; J. G. Loken; J. M. Lopez; D. Loukas; P. Lutz; L. Lyons; J N MacNaughton; G. Maehlum; J. R. Mahon; A. Maio; T. G. M. Malmgren; V. Malychev; F. Mandl; J. Marco; R P Marco; B. Marechal; M. Margoni; J. C. Marin; C. Mariotti; A. Markou; C. Martinez-Rivero; F. Martinez-Vidal; S. Marti i Garcia; F. Matorras; C. Matteuzzi; Giorgio Matthiae; M. Mazzucato; M. Mc Cubbin; R. Mc Kay; R. Mc Nulty; J. Medbo; M. Merk; C. Meroni; S. Meyer; W. T. Meyer; A. Miagkov; M. Michelotto; E. Migliore; L. Mirabito; Winfried A Mitaroff; U. Mjoernmark; T. Moa; R. Moeller; K. Moenig; M. R. Monge; P. Morettini; H. Mueller; K. Muenich; M. Mulders; L. M. Mundim; W. J. Murray; B. Muryn; Gerald Myatt; F. Naraghi; Francesco Luigi Navarria; S. Navas; K. Nawrocki; P. Negri; S. Nemecek; W. Neumann; N. Neumeister; R. Nicolaidou; B. S. Nielsen; M. Nieuwenhuizen; V. Nikolaenko; M. Nikolenko; P. Niss; A. Nomerotski; Ainsley Normand; M. Novak; W. Oberschulte-Beckmann; V F Obraztsov; A G Olshevskii; A. Onofre; Risto Orava; G. Orazi; K. Osterberg; A. Ouraou; P. Paganini; M. Paganoni; P. Pages; R. Pain; H. Palka

1997-01-01

259

AFM image reconstruction for deformation measurements by digital image correlation  

Microsoft Academic Search

The scanner drift of the atomic force microscope (AFM) is a great disadvantage to the application of digital image correlation to micro\\/nano-scale deformation measurements. This paper has addressed the image distortion induced by the scanner drifts and developed a method to reconstruct AFM images for the successful use of AFM image correlation. It presents such a method, that is to

Yaofeng Sun; John H. L. Pang

2006-01-01

260

Spatial correlation of plasma sheet and solar wind turbulence from two point measurements  

NASA Astrophysics Data System (ADS)

Interplanetary turbulence is the best studied case of low frequency plasma turbulence and the only directly quantified instance of astrophysical turbulence. Here, correlation analysis of interplanetary magnetic and plasma sheet turbulence is carried out, using for the first time only proper two point, single time measurements, providing a key step in unraveling the space-time structure of interplanetary turbulence. Simultaneous solar magnetic field data from the ACE, Cluster, Geotail, IMP 8, and Wind spacecraft are analyzed to determine the spatial correlation function, the correlation (outer) scale, and the inner (Taylor) microscale near Earth orbit. The two standard length scales are used to determine the effective magnetic Reynold number and the other standard turbulence length scale, the Kolmogorov scale. The correlation scale is determined to be 1.2 Mkm, the Taylor scale is 2500 km, and the effective magnetic Reynolds number is calculated to be 230,000 from the ratio of the Taylor scale and the outer scale. The Cluster magnetic field data are investigated to obtain the correlation scale and the Taylor scale in the Earth's plasma sheet. The correlation scale calculated is 22,000 km, the Taylor scale is 2200 km, and the effective magnetic Reynolds number is 100. This two point correlation method provides us with a means of determining the effective magnetic Reynolds number without having to make estimates of conductivity or assumption about wave particle interactions.

Weygand, J. M.; Matthaeus, W. H.; Dasso, S.; Kivelson, M. G.

2006-12-01

261

High Frequency Click-Evoked Otoacoustic Emission Measurements Using Maximum Length Sequences  

NASA Astrophysics Data System (ADS)

The aim of the study was to compare high-frequency components (4-8 kHz) of click-evoked otoacoustic emissions (CEOAEs) recorded using two different stimulus paradigms: the double-evoked (DE) paradigm, which uses two earphones, and the rate-derived nonlinear (RDNL) paradigm, which uses maximum length sequences (MLS) in a single ear-phone. Recordings were made in 20 otologically normal ears, and the results compared in terms of the apparent stimulus artefacts, and the presence of high-frequency CEOAEs. The correlation between CEOAEs amplitudes and DPOAE amplitudes from 4-8 kHz were also calculated. The results showed that, for both paradigms, the stimulus artefacts were of similar amplitudes and had largely decayed by around 1.5-2 ms post stimulus. Though similar in amplitude, the morphology of the artefacts in the two paradigms showed some differences, suggesting a possible means of identification. The CEOAE waveforms (post 2 ms) were very similar in both paradigms, and contained significant energy from 4-8 kHz. The amplitude correlated with the mean DPOAE amplitude from 4-8 kHz (R = 0.7 p<0.001).

Lineton, B.; Sohal, R.; Harvey, E.; Thornton, A. R. D.

2011-11-01

262

Correlation of anterior segment optical coherence tomography measurements with graft trephine diameter following descemet stripping automated endothelial keratoplasty  

PubMed Central

Background To assess repeatability of the Zhongshan Assessment Program (ZAP) software measurement of Anterior Segment Optical Coherence Tomography (ASOCT) images and correlate with graft trephine diameter following Descemet Stripping Automated Endothelial Keratoplasty (DSAEK) Methods Retrospectively evaluated interventional case series. 121 consecutive eyes undergoing DSAEK over a 26 month period underwent ASOCT imaging 1month after their surgery. ASOCT images were processed using ZAP software which measured the graft and cornea parameters including anterior and posterior graft arc length and cord length, posterior cornea arc length (PCAL) and anterior chamber width. Results The graft measurements showed good repeatability on ASOCT using ZAP with high intra class coefficient and small variation in the coefficient of variation. On ASOCT, the mean recipient PCAL was 12.99+/?0.69mm and the anterior chamber width was 11.16+/?0.57mm. The mean Graft anterior arc length was 9.69+/?0.66mm and the mean Graft anterior cord length was 8.92+/?2.94mm. The mean graft posterior arc length was 9.24+/?0.75mm and the mean graft posterior cord length was 8.15+/?0.57mm. Graft posterior arc length (rho=0.788, p< 0.001) correlated best with intra-operative graft trephine diameter. The mean ratio of posterior graft arc length to PCAL was 0.712 +/? 0.056. Conclusions We have validated the repeatability of the ZAP software for DSAEK graft measurements from ASOCT images and shown that the graft arc length parameters calculated from the ASOCT images correlate well with the intra-operative graft trephine diameter. This software may help surgeons determine the optimal DSAEK graft size based on pre-operative ASOCT measurements of the recipient eye.

2012-01-01

263

Micro and Nanoscale Deformation Measurement of Surface and Internal Planes via Digital Image Correlation  

Microsoft Academic Search

The digital image correlation (DIC) technique is successfully applied across multiple length scales through the generation\\u000a of a suitable speckle pattern at each size scale. For microscale measurements, a random speckle pattern of paint is created\\u000a with a fine point airbrush. Nanoscale displacement resolution is achieved with a speckle pattern formed by solution deposition\\u000a of fluorescent silica nanoparticles. When excited,

T. A. Berfield; J. K. Patel; R. G. Shimmin; P. V. Braun; J. Lambros; N. R. Sottos

2007-01-01

264

High-temperature deformation measurements using digital-image correlation  

Microsoft Academic Search

The ability of the computer-vision technique of digital-image correlation to measure full-field in-plane surface deformations at elevated temperatures was evaluated by a series of experiments. Samples were subjected to pure translation, free thermal expansion and uniform tensile loads. Results are presented which show that the digital-image-correlation technique remains fully capable of accurate measurement of the displacements and strains on the

J. S. Lyons; J. Liu; M. A. Sutton

1996-01-01

265

Turbulence length-scales in a fan-stirred combustion bomb, measured via particle-imaging velocimetry  

NASA Astrophysics Data System (ADS)

Combustion experiments are prepared in a fan-stirred reaction bomb that provides internal combustion engine conditions. The experiments aim at the understanding of flame-turbulence interaction. To mimic in-cylinder flow conditions the turbulence properties have to be similar as in engines. The combustion bomb has a near spherical volume of approximately 0.1 m diameter. Turbulence is generated with four fans. Before actual combustion experiments can take place, the turbulence properties as a function of fan speed, i. e. energy input are studied. A particle-imaging velocimetry setup is used to measure turbulence length scales in the combustion bomb. Air at ambient pressure and temperature is seeded with high-temperature dried MgO particles. A double-pulsed Nd:YAG laser at 30mJ per pulse flash-illuminates a plane of 10 mm height in the center of the bomb. Pulse separation and laser sheet thickness are chosen to guarantee proper detection of the maximum velocities of approximately 10 m/s. A progressive scan ccd camera is used to record the scattering images and data are then processed to yield two-dimensional vector fields. Up to several hundred images per fan speed setting are recorded and mean and rms velocities are computed from these data. An automated routine evaluates the correlation function, which is then used to compute the integral length scale and Taylor scale.

Sick, Volker; Hartman, Michael

1999-11-01

266

Length variation in a specific region of the period gene correlates with differences in pupal diapause incidence in the flesh fly, Sarcophaga bullata.  

PubMed

We report differences in the length of a specific region of the circadian clock gene period (per) that correlate with different capacities for pupal diapause in the flesh fly, Sarcophaga bullata. The conspicuous difference is located in a region we refer to as the putative C-terminal photoperiodic (CP) region. The length of the CP region correlates inversely with the incidence of diapause. A deletion of 33 amino acids in this region correlates with a significant increase in the incidence of diapause, from 78.1% to 93.0%, and an insertion of 9 amino acids in the same area correlates with a drop in the diapause incidence to 4.0%. This correlation suggests a possible functional role for this region of per in photoperiodism. PMID:19186187

Han, Bing; Denlinger, David L

2009-05-01

267

Measurement of intact-core length of atomizing liquid jets by image deconvolution  

NASA Astrophysics Data System (ADS)

The investigation of liquid jet breakup and spray development is critical to the understanding of combustion phenomena in liquid propellant rocket engines. Much work has been done to characterize low-speed liquid jet breakup and dilute sprays, but atomizing jets and dense sprays have yielded few quantitative measurements due to their high liquid load fractions and hence their optical opacity. Focus was on a characteristic of the primary breakup process of round liquid jets, namely the length of the intact-liquid core. The specific application considered is that of shear-coaxial-type rocket engine injectors in which liquid oxygen is injected through the center post while high velocity gaseous hydrogen is injected through a concentric annulus, providing a shear force to the liquid jet surface. Real-time x ray radiography, capable of imaging through the dense two-phase region surrounding the liquid core, is used to make the measurements. The intact-liquid-core length data were obtained and interpreted using two conceptually different methods to illustrate the effects of chamber pressure, gas-to-liquid momentum ratio, and cavitation.

Woodward, Roger; Burch, Robert; Kuo, Kenneth; Cheung, Fan-Bill

1993-11-01

268

Modeling work zone crash frequency by quantifying measurement errors in work zone length.  

PubMed

Work zones are temporary traffic control zones that can potentially cause safety problems. Maintaining safety, while implementing necessary changes on roadways, is an important challenge traffic engineers and researchers have to confront. In this study, the risk factors in work zone safety evaluation were identified through the estimation of a crash frequency (CF) model. Measurement errors in explanatory variables of a CF model can lead to unreliable estimates of certain parameters. Among these, work zone length raises a major concern in this analysis because it may change as the construction schedule progresses generally without being properly documented. This paper proposes an improved modeling and estimation approach that involves the use of a measurement error (ME) model integrated with the traditional negative binomial (NB) model. The proposed approach was compared with the traditional NB approach. Both models were estimated using a large dataset that consists of 60 work zones in New Jersey. Results showed that the proposed improved approach outperformed the traditional approach in terms of goodness-of-fit statistics. Moreover it is shown that the use of the traditional NB approach in this context can lead to the overestimation of the effect of work zone length on the crash occurrence. PMID:23563145

Yang, Hong; Ozbay, Kaan; Ozturk, Ozgur; Yildirimoglu, Mehmet

2013-06-01

269

Effect of measurement errors in particle correlation studies  

SciTech Connect

Rapidity correlation studies could yield information on the hadronization process in the phase transition of the quark-gluon plasma. Several theorethical methodes are commonly used in these studies: the standard two particle correlation functions, the scaled factorial momenta and the split-bin correlation functions. The influence of measurement errors on the analyses using these methods is investigated as part of an R&D project of the PHENIX experiment at RHIC. Extensive Monte Carlo simulations were performed employing the FRITIOF event generator. It is found that measurement errors associated with experimental data could introduce correlation effects in uncorrelated particles spectra comparable to those arising from correlated particles. Results of this simulation work will be presented and their implications discussed.

Rosati, M.; Barrette, J.; Mark, S.K.; Normand, L.

1993-10-01

270

Study of the fractal correlation method in displacement measurement  

NASA Astrophysics Data System (ADS)

The classical digital speckle pattern, or digital image, correlation method of deformation measurement is based on gray level correlation between unformed and deformed digital images. Since the pattern of artificial random speckles and the natural texture have fractal characteristics, and their fractal dimensions represent both gray and morph information, a fractal correlation method of displacement measurement is developed in this paper. The in-plane displacement field of a body can be acquired. In order to verify the validity of the new method, an experiment has been designed and the results have been compared with those tested by gray correlation method. The calculation speed is over 20 times fast than the digital image correlation method. The results how that its precision is less than 0.05 pixels.

Hou, Zhende; Qin, Yuwen

2001-06-01

271

Intra- and inter-observer reliability of combined segmental measurement techniques for predicting immediate post-deployment intraluminal tracheal stent length in dogs.  

PubMed

This study evaluated segmental measurement techniques for predicting immediate post-deployment intraluminal tracheal stent length in dogs with naturally occurring tracheal collapse. Radiographs of 12 client-owned dogs that underwent intraluminal tracheal stent placement were retrospectively reviewed. Tracheal lengths were divided into 1, 2, 3, or 4 equal segments. Stent lengths were predicted using the widest dorsoventral height of each segment, with and without the addition of 10%, and an accompanying foreshortening chart. Techniques were compared for intra- and inter-observer reliability, and post-deployment stent length predictability. There was good to high intra- and inter-observer reliability for all segmental measurements; median intra-class correlation coefficients were 0.98 and 0.92, respectively. Measuring 2 segments without the addition of 10% to the widths was significantly more accurate in predicting immediate post-deployment stent length in terms of percent (P = 0.03) and absolute difference (P = 0.02). Segmental measuring techniques are repeatable amongst observers and may help guide stent selection. PMID:24790228

Monaco, Thomas A; Taylor, Jim A; Langenbach, Anke; Gordon, Sebastian; Vance, Eric

2014-05-01

272

Do severity measures explain differences in length of hospital stay? The case of hip fracture.  

PubMed Central

OBJECTIVE: To examine whether judgments about hospital length of stay (LOS) vary depending on the measure used to adjust for severity differences. DATA SOURCES/STUDY SETTING: Data on admissions to 80 hospitals nationwide in the 1992 MedisGroups Comparative Database. STUDY DESIGN: For each of 14 severity measures, LOS was regressed on patient age/sex, DRG, and severity score. Regressions were performed on trimmed and untrimmed data. R-squared was used to evaluate model performance. For each severity measure for each hospital, we calculated the expected LOS and the z-score, a measure of the deviation of observed from expected LOS. We ranked hospitals by z-scores. DATA EXTRACTION: All patients admitted for initial surgical repair of a hip fracture, defined by DRG, diagnosis, and procedure codes. PRINCIPAL FINDINGS: The 5,664 patients had a mean (s.d.) LOS of 11.9 (8.9) days. Cross-validated R-squared values from the multivariable regressions (trimmed data) ranged from 0.041 (Comorbidity Index) to 0.165 (APR-DRGs). Using untrimmed data, observed average LOS for hospitals ranged from 7.6 to 23.9 days. The 14 severity measures showed excellent agreement in ranking hospitals based on z-scores. No severity measure explained the differences between hospitals with the shortest and longest LOS. CONCLUSIONS: Hospitals differed widely in their mean LOS for hip fracture patients, and severity adjustment did little to explain these differences.

Shwartz, M; Iezzoni, L I; Ash, A S; Mackiernan, Y D

1996-01-01

273

Atmospheric correlation time measurements using coherent CO2 lidar  

NASA Technical Reports Server (NTRS)

A pulsed TEA-CO2 lidar with coherent detection was used to measure the correlation time of backscatter from an ensemble of atmospheric aerosol particles which are illuminated by the pulsed radiation. The correlation time of the backscatter return signal is important in studies of atmospheric turbulence and its effects on optical propagation and backscatter. If the temporal coherence of the pulse is large enough, then the temporal coherence of the return signal is dominated by the turbulence and shear for a variety of interesting atmospheric conditions. Various techniques for correlation time measurement are discussed and evaluated.

Ancellet, G. M.; Menzies, R. T.

1986-01-01

274

Correlations among adiposity measures in school-aged children  

PubMed Central

Background Given that it is not feasible to use dual x-ray absorptiometry (DXA) or other reference methods to measure adiposity in all pediatric clinical and research settings, it is important to identify reasonable alternatives. Therefore, we sought to determine the extent to which other adiposity measures were correlated with DXA fat mass in school-aged children. Methods In 1110 children aged 6.5-10.9 years in the pre-birth cohort Project Viva, we calculated Spearman correlation coefficients between DXA (n=875) and other adiposity measures including body mass index (BMI), skinfold thickness, circumferences, and bioimpedance. We also computed correlations between lean body mass measures. Results 50.0% of the children were female and 36.5% were non-white. Mean (SD) BMI was 17.2 (3.1) and total fat mass by DXA was 7.5 (3.9) kg. DXA total fat mass was highly correlated with BMI (rs=0.83), bioimpedance total fat (rs=0.87), and sum of skinfolds (rs=0.90), and DXA trunk fat was highly correlated with waist circumference (rs=0.79). Correlations of BMI with other adiposity indices were high, e.g., with waist circumference (rs=0.86) and sum of subscapular plus triceps skinfolds (rs=0.79). DXA fat-free mass and bioimpedance fat-free mass were highly correlated (rs=0.94). Conclusions In school-aged children, BMI, sum of skinfolds, and other adiposity measures were strongly correlated with DXA fat mass. Although these measurement methods have limitations, BMI and skinfolds are adequate surrogate measures of relative adiposity in children when DXA is not practical.

2013-01-01

275

Diffusion length measurements in bulk and epitaxially grown 3-5 semiconductors using charge collection microscopy  

NASA Technical Reports Server (NTRS)

Diffusion lengths and surface recombination velocities were measured in GaAs diodes and InP finished solar cells. The basic techniques used was charge collection microscopy also known as electron beam induced current (EBIC). The normalized currents and distances from the pn junction were read directly from the calibrated curves obtained while using the line scan mode in an SEM. These values were then equated to integral and infinite series expressions resulting from the solution of the diffusion equation with both extended generation and point generation functions. This expands previous work by examining both thin and thick samples. The surface recombination velocity was either treated as an unknown in a system of two equations, or measured directly using low e(-) beam accelerating voltages. These techniques give accurate results by accounting for the effects of surface recombination and the finite size of the generation volume.

Leon, R. P.

1987-01-01

276

Diffusion length measurement in bulk and epitaxially grown III-V semiconductors using charge collection microscopy  

NASA Technical Reports Server (NTRS)

Diffusion lengths and surface recombination velocities were measured in GaAs diodes and InP finished solar cells. The basic technique used was charge collection microscopy, also known as electron beam induced current (EBIC). The normalized currents and distances from the pn junction were read directly from the calibrated curves obtained while using the line-scan mode in an SEM. These values were then equated to integral and infinite series expressions resulting from the solution of the diffusion equation with both extended-generation and point-generation functions. This expands previous work by examining both thin and thick samples. The surface recombination velocity was either treated as an unknown in a system of two equations or measured directly using low e(-) beam accelerating voltages. These techniques give accurate results by accounting for the effects of surface recombination and the finite size of the generation volume.

Leon, R. P.

1987-01-01

277

Precision measurement of {pi}{pi} scattering lengths at the NA48/2 experiment  

SciTech Connect

The NA48/2 experiment at CERN [1] collected {approx}18{center_dot}10{sup 9} charged kaon decays during the years 2003/4. Along with the primary goals of the collaboration, i.e. the measurement of the CP-violating asymmetry in the K{sup {+-}}{yields}{pi}{sup {+-}}{pi}{sup +}{pi}{sup -} and K{sup {+-}}{yields}{pi}{sup {+-}}{pi}{sup 0}{pi}{sup 0} decays thanks to the simultaneous collection of K{sup +} and K{sup -} events, the collected data allowed to perform many other interesting analyses. In this paper two independent measurements of {pi}{pi} scattering lengths will be reviewed, using NA48/2 data from the K{sup {+-}}{yields}e{sup {+-}}{nu}{pi}{sup +}{pi}{sup -} decay and from the cusp effect in K{sup {+-}}{yields}{pi}{sup {+-}}{pi}{sup +}{pi}{sup -} respectively.

Venditti, Stefano [Universita di Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy)

2010-12-28

278

Accurate Leg Length Measurement in Total Hip Arthroplasty: A Comparison of Computer Navigation and a Simple Manual Measurement Device  

PubMed Central

Background Several studies have shown that better placement of the acetabular cup and femoral stem can be achieved in total hip arthroplasty (THA) by using the computer navigation system rather than the free-hand alignment methods. However, there have been no comparisons of the relevant clinical advantages in using the computer navigation as opposed to the manual intraoperative measurement devices. The purpose of this study is to determine whether the use of computer navigation can improve postoperative leg length discrepancy (LLD) compared to the use of the measurement device. Methods We performed a retrospective study comparing 30 computer-assisted THAs with 40 THAs performed using a simple manual measurement device. Results The postoperative LLD was 3.0 mm (range, 0 to 8 mm) in the computer-assisted group and 2.9 mm (range, 0 to 10 mm) in the device group. Statistically significant difference was not seen between the two groups. Conclusions The results showed good equalization of the leg lengths using both computed tomography-based navigation and the simple manual measurement device.

Kabata, Tamon; Maeda, Toru; Kajino, Yoshitomo; Tsuchiya, Hiroyuki

2014-01-01

279

Curriculum-Based Measurement Oral Reading as an Indicator of Reading Achievement: A Meta-Analysis of the Correlational Evidence  

ERIC Educational Resources Information Center

This meta-analysis summarized the correlational evidence of the association between the CBM Oral Reading measure (R-CBM) and other standardized measures of reading achievement for students in grades 1-6. Potential moderating variables were also examined (source of criterion test, administration format, grade level, length of time, and type of…

Reschly, Amy L.; Busch, Todd W.; Betts, Joseph; Deno, Stanley L.; Long, Jeffrey D.

2009-01-01

280

MaSC: mappability-sensitive cross-correlation for estimating mean fragment length of single-end short-read sequencing data  

PubMed Central

Motivation: Reliable estimation of the mean fragment length for next-generation short-read sequencing data is an important step in next-generation sequencing analysis pipelines, most notably because of its impact on the accuracy of the enriched regions identified by peak-calling algorithms. Although many peak-calling algorithms include a fragment-length estimation subroutine, the problem has not been adequately solved, as demonstrated by the variability of the estimates returned by different algorithms. Results: In this article, we investigate the use of strand cross-correlation to estimate mean fragment length of single-end data and show that traditional estimation approaches have mixed reliability. We observe that the mappability of different parts of the genome can introduce an artificial bias into cross-correlation computations, resulting in incorrect fragment-length estimates. We propose a new approach, called mappability-sensitive cross-correlation (MaSC), which removes this bias and allows for accurate and reliable fragment-length estimation. We analyze the computational complexity of this approach, and evaluate its performance on a test suite of NGS datasets, demonstrating its superiority to traditional cross-correlation analysis. Availability: An open-source Perl implementation of our approach is available at http://www.perkinslab.ca/Software.html. Contact: tperkins@ohri.ca Supplementary information: Supplementary data are available at Bioinformatics online.

Ramachandran, Parameswaran; Palidwor, Gareth A.; Porter, Christopher J.; Perkins, Theodore J.

2013-01-01

281

Image scale measurement with correlation filters in a volume holographic optical correlator  

NASA Astrophysics Data System (ADS)

A search engine containing various target images or different part of a large scene area is of great use for many applications, including object detection, biometric recognition, and image registration. The input image captured in realtime is compared with all the template images in the search engine. A volume holographic correlator is one type of these search engines. It performs thousands of comparisons among the images at a super high speed, with the correlation task accomplishing mainly in optics. However, the inputted target image always contains scale variation to the filtering template images. At the time, the correlation values cannot properly reflect the similarity of the images. It is essential to estimate and eliminate the scale variation of the inputted target image. There are three domains for performing the scale measurement, as spatial, spectral and time domains. Most methods dealing with the scale factor are based on the spatial or the spectral domains. In this paper, a method with the time domain is proposed to measure the scale factor of the input image. It is called a time-sequential scaled method. The method utilizes the relationship between the scale variation and the correlation value of two images. It sends a few artificially scaled input images to compare with the template images. The correlation value increases and decreases with the increasing of the scale factor at the intervals of 0.8~1 and 1~1.2, respectively. The original scale of the input image can be measured by estimating the largest correlation value through correlating the artificially scaled input image with the template images. The measurement range for the scale can be 0.8~4.8. Scale factor beyond 1.2 is measured by scaling the input image at the factor of 1/2, 1/3 and 1/4, correlating the artificially scaled input image with the template images, and estimating the new corresponding scale factor inside 0.8~1.2.

Zheng, Tianxiang; Cao, Liangcai; He, Qingsheng; Jin, Guofan

2013-08-01

282

Feasibility study for transuranic nuclide measurement on long-length contaminated equipment using neutron detection  

SciTech Connect

The feasibility of measuring the transuranic (TRU) nuclide content of equipment removed from Hanford`s high-level radioactive-waste tanks has been established for components heavier than about 30 kg/m (20 lbs/ft). This conclusion has been reached based on experience with the TRU assay of waste burial boxes, planned improvements to the assay equipment design and assay methodology, and experimental investigation of neutron detector performance in high gamma-ray fields. The experiments indicate that the neutron detectors presently used with Pacific Northwest Laboratory`s box scanner perform correctly in gamma-ray exposure rates of at least 3 R/h. The design of equipment proposed for measuring TRU content incorporates multiple, BF{sub 3}-gas-filled neutron counters in a configuration that is approximately 0.5 m wide and 2 m long, with polyethylene to moderate high-energy neutrons down to thermal energy. Specially developed electrical systems are used to eliminate response to gamma-rays. Performance of the assay would require 10 to 14 hours of time during which close-range access is provided to the waste and its burial container. A standard neutron source, will be placed within the burial container (before inserting components) to allow calibration of the detector. Final calculation of the TRU contamination will utilize plausible conservative assumptions concerning the spatial, isotopic, and elemental distributions of any TRU present. For long-length equipment, the detector array collects data at various positions along the length of the equipment. Separate monitoring of the cosmic-ray-induced neutron background during the assay period will provide confidence that observed changes in counts at the equipment are not related to changing background. Background measurements using the burial container and equipment {open_quotes}skid{close_quotes} will allow compensation for neutrons that are created by cosmic-ray spallation within the burial container.

Stromswold, D.C.; Peurrung, A.J.; Arthur, R.J. [and others

1995-10-01

283

Measurement of Critical correlations in an ultracold Bose gas by means of a temporal Talbot-Lau interferometery  

NASA Astrophysics Data System (ADS)

We report the results of a study of measuring the correlation length at the Lambda critical phase transition point in an ultra-cold Bose gas with a temporal Talbot-Lau (TL) interferometery. Near the critical temperature, the correlation length increase exponentially and its critical exponent factor is measured around 0.67, which is a universal value in quantum gas. In the experiment we filtered the fraction of condensate from the thermal cloud at the Lambda critical phase transition point by means of the TL interferometer technique.

Chen, Xuzong; Xiong, Wei; Zhai, Yueyang; Yue, Xuguang; Wu, Biao; Xiong, Hongwei; Zhou, Xiaoji

2014-04-01

284

Application of Flow-FISH for Dynamic Measurement of Telomere Length in Cell Division.  

PubMed

This method makes it possible to measure the fluorescence of a DNA probe in cells with known division number and targeted surface antigen. In fact, this method is a combination or consistent application of three other methods: cell tracking by vital dye, surface immunophenotyping, and flow-FISH. The idea in developing this method was to study telomere length changes in cells with known surface antigen after every new cell division. First, the in vitro cell culturing and staining with CFSE vital dye are performed. Then, cells are stained with surface MAbs labeled with biotin, followed by incubation with streptavidin-labeled fluorochrome. After that, cells are fixed with BS(3) reagent followed by the flow-FISH procedure with PNA-probe complementary to telomere DNA repeats. Finally, in one tube, it is possible to determine telomere length in surface antigen-labeled cells that have made the exact same number of divisions after incubation. Curr. Protoc. Cytom. 69:8.14.1-8.14.10. © 2014 by John Wiley & Sons, Inc. PMID:24984965

Borisov, Vyacheslav I; Korolkova, Olga Y; Kozhevnikov, Vladimir S

2014-01-01

285

Anthropometric measurements of the forearm and their correlation with the stature of Bengali adult Muslim females.  

PubMed

Stature or body height is one of the most important and useful anthropometric parameter that determine the physical identity of an individual. The study was done to estimate stature from the forearm length on one hundred and fifty Bengali adult Muslim females. This descriptive cross sectional study was done in the department of Anatomy, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh. One hundred and fifty Bengali adult Muslim female was collected from BSMMU & some urban region of Dhaka. Measurement of stature and forearm length of right and left side was taken with a standard anthropometer and a slide caliper respectively. The present study showed significant (p<0.001) positive correlation between the stature and forearm length. PMID:20639830

Laila, S Z; Begum, J A; Ferdousi, R; Parveen, S; Nurunnobi, A M; Yesmin, F

2010-07-01

286

In-Guide - Far Field Emission Spectra Measurements and Correlations.  

National Technical Information Service (NTIS)

This report describes tests conducted with the purpose of correlating In-Guide (AN/GPM-59) and Far Field emission spectra measurements. The report discusses both In-Guide and conventional Far Field measurement techniques, and identifies the error sources ...

E. W. Taylor E. F. Hjort

1967-01-01

287

The Measurement and Correlates of Career Decision Making.  

ERIC Educational Resources Information Center

This paper presents a theoretical framework for understanding career decision making (CDM); introduces an instrument, Assessment of Career Decision Making (ACDM) to measure CDM with college students; and presents correlational data on sex role and cognitive style factors hypothesized to influence CDM. The ACDM, designed to measure the Tiedeman and…

Harren, Vincent A.; Kass, Richard A.

288

Thermal Deformation Measurement by Digital Image Correlation Method  

Microsoft Academic Search

Thermal-mechanical behavior of materials and reliability assessment of semiconductor packages are two of key issues in electronic packaging. Digital image correlation method is increasingly used for thermal deformation characterization in electronic packaging in recent years. For example, the deformation measurements of solder joints in various semiconductor packages have been reported in previous studies. However, the noise effects on measurement accuracy

Yaofeng Sun; J. H. L. Pang; Xunqing Shi; J. W. Ronnie Tew

2006-01-01

289

High strain gradient measurements by using digital image correlation technique  

Microsoft Academic Search

When material characterization requires nonhomogeneous strain field measurements, the use of specific techniques is necessary. In this paper, the efficiency of the digital image correlation method for measuring in-plane displacements in the presence of high strain gradient is discussed. Three types of strain gradient have been studied: strain localization around a hole in a composite laminate, strain concentration at a

Fabienne Lagattu; Jean Brillaud; Marie-Christine Lafarie-Frenot

2004-01-01

290

An optical vernier technique for in situ measurement of the length of long Fabry-Pérot cavities  

Microsoft Academic Search

We propose a method for in situ measurement of the length of kilometre-sized Fabry-Pérot cavities in laser gravitational wave detectors. The method is based on the vernier, which occurs naturally when the laser beam incident on the cavity has a sideband. By changing the length of the cavity over several wavelengths we obtain a set of carrier resonances alternating with

M. Rakhmanov; M. Evans; H. Yamamoto

1999-01-01

291

Measuring Omega and the real correlation function from the redshift correlation function  

NASA Technical Reports Server (NTRS)

Peculiar velocities distort the correlation function of galaxies in redshift space. In the linear regime, the distortion has a characteristic quadrupole plus hexadecapole form. The amplitude of the distortion depends on the cosmological density parameter Omega. Practical formulas are derived here which can be applied to redshift galaxy catalogs to measure Omega in the linear regime. The formulas also yield the real underlying correlation function in the linear regime, corrected for peculiar velocities.

Hamilton, A. J. S.

1992-01-01

292

Exact quantum correlations of conjugate variables from joint quadrature measurements  

NASA Astrophysics Data System (ADS)

We demonstrate that for two canonically conjugate operators qˆ, pˆ, the global correlation -2, and the local correlations (p)- and (q)- can be measured exactly by Von Neumann-Arthurs-Kelly joint quadrature measurements. Here (q) and (p) denote the conditional expectation values of momentum at a given position, and position at a given momentum respectively. These correlations provide a sensitive experimental test of quantum phase space probabilities quite distinct from the probability densities of q, p. E.g. for EPR states, and entangled generalized coherent states, phase space probabilities which reproduce the correct position and momentum probability densities have to be modified to reproduce these correlations as well.

Roy, S. M.

2013-11-01

293

Distributed representation of geometrically correlated images with compressed linear measurements.  

PubMed

This paper addresses the problem of distributed coding of images whose correlation is driven by the motion of objects or the camera positioning. It concentrates on the problem where images are encoded with compressed linear measurements. We propose a geometry-based correlation model that describes the common information in pairs of images. We assume that the constitutive components of natural images can be captured by visual features that undergo local transformations (e.g., translation) in different images. We first identify prominent visual features by computing a sparse approximation of a reference image with a dictionary of geometric basis functions. We then pose a regularized optimization problem in order to estimate the corresponding features in correlated images that are given by quantized linear measurements. The correlation model is thus given by the relative geometric transformations between corresponding features. We then propose an efficient joint decoding algorithm that reconstructs the compressed images such that they are consistent with both the quantized measurements and the correlation model. Experimental results show that the proposed algorithm effectively estimates the correlation between images in multiview data sets. In addition, the proposed algorithm provides effective decoding performance that advantageously compares to independent coding solutions and state-of-the-art distributed coding schemes based on disparity learning. PMID:22345540

Thirumalai, Vijayaraghavan; Frossard, Pascal

2012-07-01

294

Spontaneous oscillation of tension and sarcomere length in skeletal myofibrils. Microscopic measurement and analysis.  

PubMed Central

We have devised a simple method for measuring tension development of single myofibrils by micromanipulation with a pair of glass micro-needles. The tension was estimated from the deflection of a flexible needle under an inverted phase-contrast microscope equipped with an image processor, so that the tension development is always accompanied by the shortening of the myofibril (auxotonic condition) in the present setup. The advantage of this method is that the measurement of tension (1/30 s for time resolution and about 0.05 micrograms for accuracy of tension measurement; 0.05 microns as a spatial resolution for displacement of the micro-needle) and the observation of sarcomere structure are possible at the same time, and the technique to hold myofibrils, even single myofibrils, is very simple. This method has been applied to study the tension development of glycerinated skeletal myofibrils under the condition where spontaneous oscillation of sarcomeres is induced, i.e., the coexistence of MgATP, MgADP and inorganic phosphate without free Ca2+. Under this condition, we found that the tension of myofibrils spontaneously oscillates accompanied by the oscillation of sarcomere length with a main period of a few seconds; the period was lengthened and shortened with stretch and release of myofibrils. A possible mechanism of the oscillation is discussed. Images FIGURE 4

Anazawa, T; Yasuda, K; Ishiwata, S

1992-01-01

295

Measurement of Minority Charge Carrier Diffusion Length in Gallium Nitride Nanowires Using Electron Beam Induced Current (EBIC).  

National Technical Information Service (NTIS)

Electron Beam Induced Current (EBIC) measurements were performed on GaN nanowires to determine minority charge carrier diffusion length, Ld. Although EBIC has been used to characterize bulk and thin film materials, very little is known about near contact ...

C. P. Ong

2009-01-01

296

Time domain measures of inter-channel EEG correlations: a comparison of linear, nonparametric and nonlinear measures.  

PubMed

Correlations between ten-channel EEGs obtained from thirteen healthy adult participants were investigated. Signals were obtained in two behavioral states: eyes open no task and eyes closed no task. Four time domain measures were compared: Pearson product moment correlation, Spearman rank order correlation, Kendall rank order correlation and mutual information. The psychophysiological utility of each measure was assessed by determining its ability to discriminate between conditions. The sensitivity to epoch length was assessed by repeating calculations with 1, 2, 3, …, 8 s epochs. The robustness to noise was assessed by performing calculations with noise corrupted versions of the original signals (SNRs of 0, 5 and 10 dB). Three results were obtained in these calculations. First, mutual information effectively discriminated between states with less data. Pearson, Spearman and Kendall failed to discriminate between states with a 1 s epoch, while a statistically significant separation was obtained with mutual information. Second, at all epoch durations tested, the measure of between-state discrimination was greater for mutual information. Third, discrimination based on mutual information was more robust to noise. The limitations of this study are discussed. Further comparisons should be made with frequency domain measures, with measures constructed with embedded data and with the maximal information coefficient. PMID:24465281

Bonita, J D; Ambolode, L C C; Rosenberg, B M; Cellucci, C J; Watanabe, T A A; Rapp, P E; Albano, A M

2014-02-01

297

Accuracy of axial length measurements from immersion B-scan ultrasonography in highly myopic eyes  

PubMed Central

AIM To evaluate the accuracy of axial length (AL) measurements obtained from immersion B-scan ultrasonography (immersion B-scan) for intraocular lens (IOL) power calculation in patients with high myopia and cataracts. METHODS Immersion B-scan, contact A-scan ultrasonography (contact A-scan), and the IOLMaster were used to preoperatively measure the AL in 102 eyes from 102 patients who underwent phacoemulsification and IOL implantation. Patients were divided into two groups according to the AL: one containing patients with 22 mm?AL<26 mm(group A) and the other containing patients with AL?26 mm (group B). The mean error (ME) was calculated from the difference between the AL measurement methods predicted refractive error and the actual postoperative refractive error. RESULTS In group A, ALs measured by immersion B-scan (23.48±1.15) didn't differ significantly from those measured by the IOLMaster (23.52±1.17) or from those by contact A-scan (23.38±1.20). In the same group, the standard deviation (SD) of the mean error (ME) of immersion B-scan (-0.090±0.397 D) didn't differ significantly from those of IOLMaster (-0.095±0.411 D) and contact A-scan (-0.099±0.425 D). In group B, ALs measured by immersion B-scan (27.97±2.21 mm) didn't differ significantly from those of the IOLMaster (27.86±2.18 mm), but longer than those measured by Contact A-scan (27.75±2.23 mm, P=0.009). In the same group, the standard deviation (SD) of the mean error (ME) of immersion B-scan (-0.635±0.157 D) didn't differ significantly from those of the IOLMaster (-0.679±0.359 D), but differed significantly from those of contact A-scan (-0.953±1.713 D, P=0.028). CONCLUSION Immersion B-scan exhibits measurement accuracy comparable to that of the IOLMaster, and is thus a good alternative in measuring AL in eyes with high myopia when the IOLMaster can't be used, and it is more accurate than the contact A-scan.

Yang, Qing-Hua; Chen, Bing; Peng, Guang-Hua; Li, Zhao-Hui; Huang, Yi-Fei

2014-01-01

298

Length, width and centroid distance as measures of teams tactical performance in youth football.  

PubMed

Small-sided games are commonly used in training and teaching contexts of football. However, few studies have focused on the tactical implications of this type of drills. The aim of this study is to identify how tactical collective behaviour varies with age in different small-sided game formats. We investigated the in-game field position in three different age groups of youth football players [under-9 (n=10; age = 8.5 ± 0.53), under-11 (n=10; age = 10.4 ± 0.52) and under-13 (n=10; age = 12.7 ± 0.48)], participating in two different small-sided game conditions (GK + 3 × 3 + GK and GK + 4 × 4 + GK). A team variable was created based on the players' length per width ratio (lpwratio), and a match variable was calculated as the distance between the centroid of the two teams. Results show that team variable values were influenced by the age of the players, as younger teams tend to present a higher value of lpwratio in their dispersion on the pitch. The variability of this variable also showed a decrease for teams with older players, suggesting a more consistent application of the width (stretching and creating space) and concentration (compressing into a confined area) principles of play and reflecting a higher level of collective tactical behaviour. Match variable showed a larger centroid distance for the older age groups in comparison with the younger players in the GK + 3 × 3 + GK, while all age groups demonstrated similar large centroid distances in the GK + 4 × 4 + GK game format. These results suggest that length and width ratio and centroid distance are useful measures of tactical performance in small-sided games in youth football. PMID:24444244

Folgado, Hugo; Lemmink, Koen A P M; Frencken, Wouter; Sampaio, Jaime

2014-01-01

299

Comparative Study of Bunch Length And Arrival Time Measurements at FLASH  

SciTech Connect

Diagnostic devices to precisely measure the longitudinal electron beam profile and the bunch arrival time require elaborate new instrumentation techniques. At FLASH, two entirely different methods are used. The bunch profile can be determined with high precision by a transverse deflecting RF structure, but the method is disruptive and does not allow to monitor multiple bunches in a macro-pulse train. It is therefore complemented by two non-disruptive electrooptical devices, called EO and TEO. The EO setup uses a dedicated diagnostic laser synchronized to the machine RF. The longitudinal electron beam profile is encoded in the intensity profile of a chirped laser pulse and analyzed by looking at the spectral composition of the pulse. The second setup, TEO, utilizes the TiSa-based laser system used for pump-probe experiments. Here, the temporal electron shape is encoded into the spatial dimension of the laser pulse by an intersection angle between the laser and the electron beam at the EO-crystal. In this paper, we present a comparative study of bunch length and arrival time measurements performed simultaneously with all three experimental techniques.

Schlarb, H.; Azima, A.; Dusterer, S.; Huning, M.; Knabbe, E.A.; Roehrs, M.; Rybnikov, V.; Schmidt, B.; Steffen, B.; /DESY; Ross, M.C.; /SLAC; Schmueser, P.; Winter, A.; /Hamburg U.

2007-04-16

300

Acoustic ship signature measurements by cross-correlation method.  

PubMed

Cross-correlation methods were applied for the estimation of the power spectral density and modulation spectrum of underwater noise generated by moving vessels. The cross-correlation of the signal from two hydrophones allows the separation of vessel acoustic signatures in a busy estuary. Experimental data recorded in the Hudson River are used for demonstration that cross-correlation method measured the same ship noise and ship noise modulation spectra as conventional methods. The cross-correlation method was then applied for the separation of the acoustic signatures of two ships present simultaneously. Presented methods can be useful for ship traffic monitoring and small ship classification, even in noisy harbor environments. PMID:21361436

Fillinger, Laurent; Sutin, Alexander; Sedunov, Alexander

2011-02-01

301

The comparison of the lengths and diameters of main bronchi measured from two-dimensional and three-dimensional images in the same patients  

PubMed Central

Background Recently, multi-planar reconstruction of the three-dimensional (3D) spiral chest CT scan has demonstrated superiority in the evaluation of the tracheobronchial tree. The goal of this study was to measure the lengths of the right and left main bronchi and their anteroposterior (AP) and transverse (TR) diameters using the 3D and two-dimensional (2D) images in the same adult respectively, and to evaluate the degree of correlation between them. Methods We measured the lengths of the right and left main bronchi from the carina to the first of their branches and the AP and TR diameters at the mid-portion of the right main bronchus and 2 cm below the carina in the left main bronchus. We determined the size of the left-sided double-lumen tube (DLT) based on the measured AP diameter of the left main bronchus from the 3D and 2D images, respectively. Results There was moderate correlation between the lengths of both main bronchi obtained from the 3D images and the 2D images, and between the AP diameter of the left main bronchus obtained from the 3D images and the 2D images. Same sized DLTs were estimated in 69% of the men and 34% of the women. Conclusions The lengths of the right and left main bronchi and their AP and TR diameters obtained from 3D images were not strongly correlated with those from 2D images. Therefore, a further study is needed to verify the superiority of 3D images in selecting the appropriate size of left-sided DLT.

Lee, Jeong Woo; Choi, Jin-Wook; Han, Young-Jin; Lee, Jun-Rae

2014-01-01

302

Measuring short electron bunch lengths using coherent smith-purcell radiation  

DOEpatents

A method is provided for directly determining the length of sub-picosecond electron bunches. A metallic grating is formed with a groove spacing greater than a length expected for the electron bunches. The electron bunches are passed over the metallic grating to generate coherent and incoherent Smith-Purcell radiation. The angular distribution of the coherent Smith-Purcell radiation is then mapped to directly deduce the length of the electron bunches.

Nguyen, Dinh C. (Los Alamos, NM)

1999-01-01

303

Measuring short electron bunch lengths using coherent Smith-Purcell radiation  

DOEpatents

A method is provided for directly determining the length of sub-picosecond electron bunches. A metallic grating is formed with a groove spacing greater than a length expected for the electron bunches. The electron bunches are passed over the metallic grating to generate coherent and incoherent Smith-Purcell radiation. The angular distribution of the coherent Smith-Purcell radiation is then mapped to directly deduce the length of the electron bunches. 8 figs.

Nguyen, D.C.

1999-03-30

304

Correlation measurements in Z? ?+?- and the ? neutrino helicity  

NASA Astrophysics Data System (ADS)

Using data collected with the ALEPH detector at LEP correlations between the decay products of the ? + and ? - produced in the decay of the Z have been measured. The measurements performed in the decays ?? ?? and ?? ?? place limits on deviations from the Standard Model. These are given by the parameter ? with ? = -1 for the Standard Model. The measured values are ?? = -0.95 ± 0.11 ± 0.05 and ?? = -1.03 ± 0.11 ± 0.05. For models which predict ?? = ?? = ? - interpreted as the average ? neutrino helicity - the measurement is ? = -0.99 ± 0.07 ± 0.04.

Buskulic, D.; de Bonis, I.; Decamp, D.; Ghez, P.; Goy, C.; Lees, J.-P.; Minard, M.-N.; Pietrzyk, B.; Ariztizabal, F.; Comas, P.; Crespo, J. M.; Delfino, M.; Efthymiopoulos, I.; Fernandez, E.; Fernandez-Bosman, M.; Gaitan, V.; Garrido, Ll.; Mattison, T.; Pacheco, A.; Padilla, C.; Pascual, A.; Creanza, D.; de Palma, M.; Farilla, A.; Iaselli, G.; Maggi, G.; Marinelli, N.; Natali, S.; Nuzzo, S.; Ranieri, A.; Raso, G.; Romano, F.; Ruggieri, F.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Zito, G.; Chai, Y.; Hu, H.; Huang, D.; Huang, X.; Lin, J.; Wang, T.; Xie, Y.; Xu, D.; Xu, R.; Zhang, J.; Zhang, L.; Zhao, W.; Bonvicini, G.; Boudreau, J.; Casper, D.; Drevermann, H.; Forty, R. W.; Ganis, G.; Gay, C.; Girone, M.; Hagelberg, R.; Harvey, J.; Hilgart, J.; Jacobsen, R.; Jost, B.; Knobloch, J.; Lehraus, I.; Maggi, M.; Markou, C.; Martinez, M.; Mato, P.; Meinhard, H.; Minten, A.; Miquel, R.; Moser, H.-G.; Palazzi, P.; Pater, J. R.; Perlas, J. A.; Perrodo, P.; Pusztaszeri, J.-F.; Ranjard, F.; Rolandi, L.; Rothberg, J.; Ruan, T.; Saich, M.; Schlatter, D.; Schmelling, M.; Sefkow, F.; Tejessy, W.; Tomalin, I. R.; Veenhof, R.; Wachsmuth, H.; Wasserbaech, S.; Wiedenmann, W.; Wildish, T.; Witzeling, W.; Wotschack, J.; Ajaltouni, Z.; Bardadin-Otwinowska, M.; Barres, A.; Boyer, C.; Falvard, A.; Gay, P.; Guicheney, C.; Henrard, P.; Jousset, J.; Michel, B.; Montret, J.-C.; Pallin, D.; Perret, P.; Podlyski, F.; Proriol, J.; Saadi, F.; Fearnley, T.; Hansen, J. B.; Hansen, J. D.; Hansen, J. R.; Hansen, P. H.; Møllerud, R.; Nilsson, B. S.; Kyriakis, A.; Simopoulou, E.; Siotis, I.; Vayaki, A.; Zachariadou, K.; Badier, J.; Blondel, A.; Bonneaud, G.; Brient, J. C.; Bourdon, P.; Fouque, G.; Orteu, S.; Rougé, A.; Rumpf, M.; Tanaka, R.; Verderi, M.; Videau, H.; Candlin, D. J.; Parsons, M. I.; Veitch, E.; Focardi, E.; Moneta, L.; Parrini, G.; Corden, M.; Georgiopoulos, C.; Jaffe, D. E.; Levinthal, D.; Antonelli, A.; Baldini, R.; Bencivenni, G.; Bologna, G.; Bossi, F.; Campana, P.; Capon, G.; Cerutti, F.; Chiarella, V.; Felici, G.; Laurelli, P.; Mannocchi, G.; Murtas, F.; Murtas, G. P.; Passalacqua, L.; Pepe-Altarelli, M.; Colrain, P.; Ten Have, I.; Lynch, J. G.; Maitland, W.; Morton, W. T.; Raine, C.; Reeves, P.; Scarr, J. M.; Smith, K.; Smith, M. G.; Thompson, A. S.; Turnbull, R. M.; Brandl, B.; Braun, O.; Geweniger, C.; Hanke, P.; Hepp, V.; Kluge, E. E.; Maumary, Y.; Putzer, A.; Rensch, B.; Stahl, A.; Tittel, K.; Wunsch, M.; Beuselinck, R.; Binnie, D. M.; Cameron, W.; Cattaneo, M.; Colling, D. J.; Dornan, P. J.; Hassard, J. F.; Lieske, N. M.; Moutoussi, A.; Nash, J.; Patton, S.; Payne, D. G.; Phillips, M. J.; San Martin, G.; Sedgbeer, J. K.; Wright, A. G.; Girtler, P.; Kuhn, D.; Rudolph, G.; Vogl, R.; Bowdery, C. K.; Brodbeck, T. J.; Finch, A. J.; Foster, F.; Hughes, G.; Jackson, D.; Keemer, N. R.; Nuttall, M.; Patel, A.; Sloan, T.; Snow, S. W.; Whelan, E. P.; Greene, A. M.; Kleinknecht, K.; Raab, J.; Renk, B.; Sander, H.-G.; Schmidt, H.; Walther, S. M.; Wanke, R.; Wolf, B.; Zimmermann, A.; Bencheikh, A. M.; Benchouk, C.; Bonissent, A.; Calvet, D.; Carr, J.; Coyle, P.; Diaconu, C.; Drinkard, J.; Etienne, F.; Nicod, D.; Payre, P.; Roos, L.; Rousseau, D.; Schwemling, P.; Talby, M.; Adlung, S.; Assmann, R.; Bauer, C.; Blum, W.; Brown, D.; Cattaneo, P.; Dehning, B.; Dietl, H.; Dydak, F.; Frank, M.; Halley, A. W.; Jakobs, K.; Lauber, J.; Lütjens, G.; Lutz, G.; Männer, W.; Richter, R.; Schröder, J.; Schwarz, A. S.; Settles, R.; Seywerd, H.; Stierlin, U.; Stiegler, U.; St. Denis, R.; Wolf, G.; Alemany, R.; Boucrot, J.; Callot, O.; Cordier, A.; Davier, M.; Duflot, L.; Grivaz, J.-F.; Heusse, Ph.; Janot, P.; Kimfn, D. W.; Le Diberder, F.; Lefrançois, J.; Lutz, A.-M.; Schune, M.-H.; Veillet, J.-J.; Videau, I.; Zhang, Z.; Abbaneo, D.; Bagliesi, G.; Batignani, G.; Bottigli, U.; Bozzi, C.; Calderini, G.; Carpinelli, M.; Ciocci, M. A.; Ciulli, V.; Dell'Orso, R.; Ferrante, I.; Fidecaro, F.; Foà, L.; Forti, F.; Giassi, A.; Giorgi, M. A.; Gregorio, A.; Ligabue, F.; Lusiani, A.; Mannelli, E. B.; Marrocchesi, P. S.; Messineo, A.; Palla, F.; Rizzo, G.; Sanguinetti, G.; Spagnolo, P.; Steinberger, J.; Tenchini, R.; Tonelli, G.; Triggiani, G.; Valassi, A.; Vannini, C.; Venturi, A.; Verdini, P. G.; Walsh, J.; Betteridge, A. P.; Gao, Y.; Green, M. G.; Johnson, D. L.; March, P. V.; Medcalf, T.; Mir, Ll. M.; Quazi, I. S.; Strong, J. A.; Botterill, D. R.; Clifft, R. W.; Edgecock, T. R.; Haywood, S.; Norton, P. R.; Thompson, J. C.; Bloch-Devaux, B.; Colas, P.; Duarte, H.; Emery, S.; Kozanecki, W.; Lançon, E.; Lemaire, M. C.; Locci, E.; Marx, B.; Perez, P.; Rander, J.; Renardy, J.-F.; Rosowsky, A.; Roussarie, A.; Schuller, J.-P.; Schwindling, J.; Si Mohand, D.; Vallage, B.; Johnson, R. P.; Litke, A. M.; Taylor, G.; Wear, J.; Babbage, W.; Booth, C. N.; Buttar, C.

1994-01-01

305

Length Scales and Structural Dynamics in Nematogen Pseudonematic Domains Measured with 2D IR Vibrational Echoes and Optical Kerr Effect Experiments.  

PubMed

Nematogen liquids in the isotropic phase are macroscopically homogeneous but on multinanometer length scales have pseudonematic domains with correlation lengths that grow as the isotropic to nematic phase transition temperature (TNI) is approached from above. Orientational relaxation of nematogens in the isotropic phase manifests as two fast power laws and a slow exponential decay when measured by optical heterodyne detected optical Kerr effect (OHD-OKE) experiments. The long time exponential relaxation is associated with complete randomization of pseudonematic domains. We examine the effect of local orientational correlation on spectral diffusion (structural evolution) experienced by a vibrational probe molecule within the pseudonematic domains of 4-cyano-4'-pentylbiphenyl (5CB) using two-dimensional infrared (2D IR) vibrational echo spectroscopy. The addition of low concentration 4-pentyl-4'-thiocyanobiphenyl (5SCB) as a long-lived vibrational probe to 5CB is shown to lower TNI of the sample slightly, but the fast power law dynamics and exponential decays observed by OHD-OKE spectroscopy are unchanged. We compare the complete orientational relaxation and spectral diffusion for samples of 5SCB in 5CB to 5SCB in 4-pentylbiphenyl (5B) at four temperatures above TNI. 5B has a molecular structure similar to 5CB but is not a nematogen. At all but the lowest temperature, the spectral diffusion in 5CB and 5B is described well as a triexponential decay with very similar time constants. The results demonstrate that the presence of local orientational order at temperatures well above TNI does not affect the spectral diffusion (structural evolution) within pseudonematic domains when the correlation lengths are short. However, when the temperature of the sample is held very close to TNI, the spectral diffusion in 5CB slows dramatically while that in 5B does not. It is only as the correlation length becomes very long that its presence impacts the spectral diffusion (structural fluctuations) sensed by the vibrational probes located in pseudonematic domains. The orientational relaxation is modeled with schematic mode coupling theory (MCT). Fitting with MCT provides density and orientational correlation functions. The density correlation decays are similar for 5B and 5CB, but the orientational correlation decays are much slower for 5CB. Additionally, the time dependence of the spectral diffusion in 5CB is strikingly similar to that of the density correlation function decay, while the orientational correlation function decay is far too slow to contribute to the spectral diffusion. Therefore, density fluctuations are likely the source of spectral diffusion at temperatures at least 5 K above TNI. PMID:24521155

Sokolowsky, Kathleen P; Bailey, Heather E; Fayer, Michael D

2014-07-17

306

Measurement of surface profile using digital image correlation  

Microsoft Academic Search

Presented in this paper is the development of a system for measuring surface profile using digital image correlation. All\\u000a needed equations for camera calibration and system profile measurements are shown. Equations included needed transformation\\u000a to account for subset perspective distortions. The system is capable of an accuracy of 1\\/20,000 of the camera-to-object distance.\\u000a Experimental results are shown for several cases,

S. R. McNeill; M. A. Sutton; Z. Miao; J. Ma

1997-01-01

307

Quantum Discord: A Measure of the Quantumness of Correlations  

Microsoft Academic Search

Two classically identical expressions for the mutual information generally differ when the systems involved are quantum. This difference defines the quantum discord. It can be used as a measure of the quantumness of correlations. Separability of the density matrix describing a pair of systems does not guarantee vanishing of the discord, thus showing that absence of entanglement does not imply

Harold Ollivier; Wojciech H. Zurek

2002-01-01

308

Correlation theory applied to work-flow measurement  

Microsoft Academic Search

Correlation theory is applied to a production system to evaluate its potentialities for the measurement of work-flow rates. Results obtained by this method are compared with those obtained from a, two-month shop-floor study and the agreement is good. The wider implications of the approach for production control are discussed.

A. S. CARRIE

1971-01-01

309

Effects of Length and Linguistic Complexity on Temporal Acoustic Measures in Apraxia of Speech.  

ERIC Educational Resources Information Center

A study was conducted of five individuals exhibiting acquired apraxia of speech to examine vowel durations and length of intervals between words produced in utterances that varied in type of utterance as well as in length. Results found evidence that longer vowel durations were a salient characteristic of apraxia of speech. (CR)

Strand, Edythe A.; McNeil, Malcolm R.

1996-01-01

310

Space Plasma Particle Correlation: Theory, Simulation and Measurement  

NASA Astrophysics Data System (ADS)

Historically particle correlator instruments have provided insight into the missing link of experimental space plasma physics. Space plasma instrumentation is otherwise split into the dichotomy imposed by particle-wave duality, but the correlator bridges this di- vision by detecting and measuring the interaction between wave and particle. In the past the theory of particle correlation in space plasmas has mainly dealt with reso- nant particles bunched within potential waves. To detect this, the technique employed was to Fourier transform the autocorrelation of the detected particles: a line spectrum would then be interpreted as a particle-wave resonance. In this poster we develope a theory in which derives analytical expressions for particle autocorrelation functions and we argue that the particle correlation is involved in more than just resonant parti- cles. Indeed it can be employed to study the microphysics of space plasmas. We also discuss various techniques for analysing particle correlator data which complements and in certain cases surpasses the Fourier technique. The theory and techniques are illustrated and applied to data from the DWP correlator on the Cluster space mission. We also show Monte-Carlo simulations of the microscale physics involved in counting electrons in a space plasma.

Carozzi, T. D.; Gough, M. P.; Buckley, A. M.; Beloff, N.

311

Quantitative evaluation of cross correlation between two finite-length time series with applications to single-molecule FRET.  

PubMed

The statistical properties of the cross correlation between two time series has been studied. An analytical expression for the cross correlation function's variance has been derived. On the basis of these results, a statistically robust method has been proposed to detect the existence and determine the direction of cross correlation between two time series. The proposed method has been characterized by computer simulations. Applications to single-molecule fluorescence spectroscopy are discussed. The results may also find immediate applications in fluorescence correlation spectroscopy (FCS) and its variants. PMID:18847232

Hanson, Jeffery A; Yang, Haw

2008-11-01

312

Sonographic measurement of renal size in patients undergoing chronic hemodialysis: Correlation with residual renal function  

PubMed Central

Previous studies have reported that renal size may change when the function is compromised. However, it is not known whether sonographically measured renal size reflects the residual renal function (RRF) in patients undergoing chronic hemodialysis. A total of 140 patients undergoing chronic hemodialysis (?3 months) were investigated in the present study. The patients were divided into two groups according to the daily urine volume: Individuals with RRF (RRF+ group; ?200 ml; n=65) and without RRF (RRF? group; <200 ml; n=75). Renal sizes were measured using sonography and renal volumes were calculated with the ellipsoid formula. Univariable and multivariable stepwise forward logistic regression analyses were performed to examine the correlation between the presence of RRF and various variables. The results indicated that there were statistically significant differences (P<0.001) between the RRF+ and RRF? groups with regard to renal length, width, thickness and volume of the left (length, 7.9±1.2 vs. 6.8±1.2 cm; volume, 60.0±26.7 vs. 40.2±18.1 ml, respectively) and right (length, 7.6±1.2 vs. 6.7±1.2 cm; volume, 50.2±26.5 vs. 33.9±15.3 ml, respectively) sides of the kidney. Multivariable stepwise forward logistic regression analyses showed that the mean renal length or volume and hemodialysis duration were independent predictors of the presence of RRF. Therefore, renal size assessment by ultrasonography may be useful for RRF evaluation in patients undergoing chronic hemodialysis.

ZHANG, WU-XING; ZHANG, ZHI-MIN; CAO, BING-SHENG; ZHOU, WEI

2014-01-01

313

Rheology of fluids measured by correlation force spectroscopy  

NASA Astrophysics Data System (ADS)

We describe a method, correlation force spectrometry (CFS), which characterizes fluids through measurement of the correlations between the thermally stimulated vibrations of two closely spaced micrometer-scale cantilevers in fluid. We discuss a major application: measurement of the rheological properties of fluids at high frequency and high spatial resolution. Use of CFS as a rheometer is validated by comparison between experimental data and finite element modeling of the deterministic ring-down of cantilevers using the known viscosity of fluids. The data can also be accurately fitted using a harmonic oscillator model, which can be used for rapid rheometric measurements after calibration. The method is non-invasive, uses a very small amount of fluid, and has no actively moving parts. It can also be used to analyze the rheology of complex fluids. We use CFS to show that (non-Newtonian) aqueous polyethylene oxide solution can be modeled approximately by incorporating an elastic spring between the cantilevers.

Radiom, Milad; Robbins, Brian; Honig, Christopher D. F.; Walz, John Y.; Paul, Mark R.; Ducker, William A.

2012-04-01

314

Imaging cross-correlation FROG: measuring ultrashort, complex, spatiotemporal fields.  

PubMed

We present imaging cross-correlation frequency-resolved optical gating (ImXFROG), a new method for the spatiotemporal phase retrieval of ultrashort pulses. It is demonstrated that ImXFROG can measure phase and intensity of arbitrary, spatiotemporally distorted pulses with femtosecond resolution and up to 10(7) independent variables. ImXFROG is implemented as a plug-in upgrade to an existing correlator and used to demonstrate the reconstruction of highly complex, optical pulses with femtosecond features and massive spatiotemporal distortion. PMID:24216822

Eilenberger, Falk; Brown, Alexander; Minardi, Stefano; Pertsch, Thomas

2013-11-01

315

Correlative measurement opportunities between ATLAS-1 and UARS experiments  

NASA Technical Reports Server (NTRS)

The first ATmospheric Laboratory for Applications and Science (ATLAS-1) mission was flown aboard the Space Shuttle from March 24 to April 2, 1992. The ATLAS-1 instruments provided a large number of measurements which were coincident with observations from experiments on the Upper Atmosphere Research Satellite (UARS). During the ATLAS-1 mission, simulations were performed to predict when and where coincident measurements between ATLAS and UARS instruments would occur. These predictions were used to develop instrument operation schedules to maximize the correlative opportunities between the two satellites. Results of the simulations provide valuable information for the ATLAS and UARS scientists to compare measurements between various instruments on the two satellites.

Harrison, Edwin F.; Denn, Fred M.; Gibson, Gary G.

1992-01-01

316

Viscoelastic properties of normal and infarcted myocardium measured by a multifrequency shear wave method: comparison with pressure-segment length method.  

PubMed

Our aims were (i) to compare in vivo measurements of myocardial elasticity by shear wave dispersion ultrasound vibrometry (SDUV) with those by the conventional pressure-segment length method, and (ii) to quantify changes in myocardial viscoelasticity during systole and diastole after reperfused acute myocardial infarction. The shear elastic modulus (?1) and viscous coefficient (?2) of left ventricular myocardium were measured by SDUV in 10 pigs. Young's elastic modulus was independently measured by the pressure-segment length method. Measurements made with the SDUV and pressure-segment length methods were strongly correlated. At reperfusion, ?1 and ?2 in end-diastole were increased. Less consistent changes were found during systole. In all animals, ?1 increased linearly with left ventricular pressure developed during systole. Preliminary results suggest that ?1 is preload dependent. This is the first study to validate in vivo measurements of myocardial elasticity by a shear wave method. In this animal model, the alterations in myocardial viscoelasticity after a myocardial infarction were most consistently detected during diastole. PMID:24814645

Pislaru, Cristina; Urban, Matthew W; Pislaru, Sorin V; Kinnick, Randall R; Greenleaf, James F

2014-08-01

317

Optical vernier technique for in-situ measurement of the length of long Fabry-Perot cavities  

Microsoft Academic Search

We propose a method for in-situ measurement of the length of kilometer size\\u000aFabry-Perot cavities in laser gravitational wave detectors. The method is based\\u000aon the vernier, which occurs naturally when the laser incident on the cavity\\u000ahas a sideband. By changing the length of the cavity over several wavelengths\\u000awe obtain a set of carrier resonances alternating with sideband

M. Rakhmanov; M. Evans; H. Yamamoto

1998-01-01

318

Non-contact measurement of linear thermal expansion coefficients of solid materials by infrared image correlation  

NASA Astrophysics Data System (ADS)

A new non-contact optical method (IIC, infrared image correlation) for the determination of the coefficients of thermal expansion of solid materials is presented. The proposed method is based on performing a digital image correlation between thermal images recorded at different temperatures by means of an infrared camera. It allows the coefficient of thermal expansion of both isotropic and anisotropic solid materials to be determined by measuring simultaneously the fractional increase in length and the actual thermal field over a small region of interest in which a dual-emissivity stochastic speckle pattern has been created. The results reported in this paper prove the effectiveness of the proposed method that can be applied either to carry out reference measurements in laboratory or to evaluate thermal stresses and strains on structural components in-field.

Montanini, R.; Freni, F.

2014-01-01

319

Reliability-guided digital image correlation for image deformation measurement  

SciTech Connect

A universally applicable reliability-guided digital image correlation (DIC) method is proposed for reliable image deformation measurement. The zero-mean normalized cross correlation (ZNCC) coefficient is used to identify the reliability of the point computed. The correlation calculation begins with a seed point and is then guided by the ZNCC coefficient. That means the neighbors of the point with the highest ZNCC coefficient in a queue for computed points will be processed first. Thus the calculation path is always along the most reliable direction, and possible error propagation of the conventional DIC method can be avoided. The proposed novel DIC method is universally applicable to the images with shadows, discontinuous areas, and deformation discontinuity. Two image pairs were used to evaluate the performance of the proposed technique, and the successful results clearly demonstrate its robustness and effectiveness.

Pan Bing

2009-03-10

320

Neural Correlates of Temporal Auditory Processing in Developmental Dyslexia during German Vowel Length Discrimination: An fMRI Study  

ERIC Educational Resources Information Center

This fMRI study investigated phonological vs. auditory temporal processing in developmental dyslexia by means of a German vowel length discrimination paradigm (Groth, Lachmann, Riecker, Muthmann, & Steinbrink, 2011). Behavioral and fMRI data were collected from dyslexics and controls while performing same-different judgments of vowel duration in…

Steinbrink, Claudia; Groth, Katarina; Lachmann, Thomas; Riecker, Axel

2012-01-01

321

Wound shape geometry measurements correlate to eventual wound healing.  

PubMed

Wound geometry measurements have long been associated with wound-healing outcomes but there is little published evidence to support this. We studied serial wound tracings of 338 venous leg ulcers (VLUs) that had been followed during a controlled, prospective, randomized pivotal trial of two topical wound treatments, to determine whether the relationship between wound surface area and wound perimeter planimetry measurements, as well as the qualitative assessment of wound shape, could be correlated to wound-healing outcomes. VLUs that transitioned to a more convex wound shape, and maintained a linear relationship between their wound margin size and wound surface area size, had faster healing rates and were more likely to completely heal by 12 weeks (odds ratio=4.84, p=0.001). VLUs that initially presented with isolated areas of epithelium within the wound margins, large concavities, or were segmented into multiple ulcers typically had a poorer linear correlation between their margins and their surface area. Only 18 out of 134 (13%) VLUs with a linear r(2)<0.80 eventually reached full wound closure, vs. 43% (102 of 270) of the remaining wounds with an r(2)> or =0.80 (Fisher's exact p<0.001). We believe our results show that the proportional relationship between one-dimensional perimeter and area measurements accurately correlates to the healing progress of the wound. Wounds that do not correlate to this linear relationship (concave geometries or multiple islands of healing) may be physiologically different than wounds that have good linear correlation, which we concluded through the analysis of wound acetate tracings. PMID:19320884

Cardinal, Matthew; Eisenbud, David E; Armstrong, David G

2009-01-01

322

Multiple length and time scales of dynamic heterogeneities in model glass-forming liquids: A systematic analysis of multi-point and multi-time correlations  

NASA Astrophysics Data System (ADS)

We report an extensive and systematic investigation of the multi-point and multi-time correlation functions to reveal the spatio-temporal structures of dynamic heterogeneities in glass-forming liquids. Molecular dynamics simulations are carried out for the supercooled states of various prototype models of glass-forming liquids such as binary Kob-Andersen, Wahnström, soft-sphere, and network-forming liquids. While the first three models act as fragile liquids exhibiting super-Arrhenius temperature dependence in their relaxation times, the last is a strong glass-former exhibiting Arrhenius behavior. First, we quantify the length scale of the dynamic heterogeneities utilizing the four-point correlation function. The growth of the dynamic length scale with decreasing temperature is characterized by various scaling relations that are analogous to the critical phenomena. We also examine how the growth of the length scale depends upon the model employed. Second, the four-point correlation function is extended to a three-time correlation function to characterize the temporal structures of the dynamic heterogeneities based on our previous studies [K. Kim and S. Saito, Phys. Rev. E 79, 060501(R) (2009); and J. Chem. Phys. 133, 044511 (2010)]. We provide comprehensive numerical results obtained from the three-time correlation function for the above models. From these calculations, we examine the time scale of the dynamic heterogeneities and determine the associated lifetime in a consistent and systematic way. Our results indicate that the lifetime of the dynamical heterogeneities becomes much longer than the ?-relaxation time determined from a two-point correlation function in fragile liquids. The decoupling between the two time scales is remarkable, particularly in supercooled states, and the time scales differ by more than an order of magnitude in a more fragile liquid. In contrast, the lifetime is shorter than the ?-relaxation time in tetrahedral network-forming strong liquid, even at lower temperatures.

Kim, Kang; Saito, Shinji

2013-03-01

323

Correlations between LDEX Measurements and the Lunar Plasma Environment  

NASA Astrophysics Data System (ADS)

The Lunar Dust Experiment (LDEX) aboard the Lunar Atmosphere and Dust Environment Explorer (LADEE) is an impact ionization dust detector capable of measuring the mass of sub-micron sized dust grains above the lunar surface. LDEX can also search for the putative population of grains with radii on the order of ~ 0.1 ?m lofted over the terminator regions by measuring the collective current of dust grains that are below the detection threshold for single impacts. This current, intended to measure the collective impact plasma from multiple small grain impacts, has also shown considerable correlations with plasma measurements from the ARTEMIS (Acceleration, Reconnection, Turbulence, & Electrodynamics of Moon's Interaction with the Sun) mission. Through LADEE's many orbits, LDEX sees time periods with very low variability, having almost no activity as well as periods with very high variability. Since this type of high activity is also observed in anti-ram pointing measurements, much of this current cannot be explained by collections of small dust grain impacts. Given this, comparisons to ARTEMIS data provide a promising way to explain such measurements. This presentation will focus on the correlations between LDEX and ARTEMIS data.

Szalay, Jamey; Horanyi, Mihaly; Poppe, Andrew; Halekas, Jasper

2014-05-01

324

Measurement and correlation of jet fuel viscosities at low temperatures  

NASA Technical Reports Server (NTRS)

Apparatus and procedures were developed to measure jet fuel viscosity for eight current and future jet fuels at temperatures from ambient to near -60 C by shear viscometry. Viscosity data showed good reproducibility even at temperatures a few degrees below the measured freezing point. The viscosity-temperature relationship could be correlated by two linear segments when plotted as a standard log-log type representation (ASTM D 341). At high temperatures, the viscosity-temperature slope is low. At low temperatures, where wax precipitation is significant, the slope is higher. The breakpoint between temperature regions is the filter flow temperature, a fuel characteristic approximated by the freezing point. A generalization of the representation for the eight experimental fuels provided a predictive correlation for low-temperature viscosity, considered sufficiently accurate for many design or performance calculations.

Schruben, D. L.

1985-01-01

325

Measurement and correlation of vapor sorption equilibria of polymer solutions  

Microsoft Academic Search

Solvent sorption equilibrium data of binary solvent\\/polymer systems were measured using a vacuum electromicrobalance. Solvents tested were benzene, cyclohexane, n-hexane, water and methanol. Rubbery polymers tested were poly(dimethylsiloxane, PDMS), poly(iso-butylene, PIB), poly(propylene oxide, PPO) and poly(vinyl alcohol, PVA). Data obtained in the present study, together with existing literature data, were correlated by both the UNIQUAC, Gibbs function (gE)-model and a

Jisoo Kim; Kyung Chul Joung; Ki-Pung Yoo; Seong Youl Bae

1998-01-01

326

A quantitative measure of phase correlations in density fields  

NASA Technical Reports Server (NTRS)

A quantitative measure of the phase correlations in a density field is presented based on the location of the maxima of the Fourier components of that field. It is found that this measue can easily detect non-Gaussian behavior either in artificially constructed density fields or those that become non-Gaussian from gravitational clustering of Gaussian initial conditions. It is found that different initial power spectra produce somewhat distinguishable signals, and the signals are robust against sparse sampling.

Scherrer, Robert J.; Melott, Adrian L.; Shandarin, Sergei F.

1991-01-01

327

Measurement of angular correlations based on secondary vertex reconstruction at  

Microsoft Academic Search

A measurement of the angular correlations between beauty and anti-beauty hadrons () produced in pp collisions at a centre-of-mass energy of 7 TeV at the CERN LHC is presented, probing for the first time the\\u000a region of small angular separation. The B hadrons are identified by the presence of displaced secondary vertices from their\\u000a decays. The B hadron angular separation

V. Khachatryan; A. M. Sirunyan; A. Tumasyan; W. Adam; T. Bergauer; M. Dragicevic; J. Erö; C. Fabjan; M. Friedl; R. Frühwirth; V. M. Ghete; J. Hammer; S. Hänsel; C. Hartl; M. Hoch; N. Hörmann; J. Hrubec; M. Jeitler; G. Kasieczka; W. Kiesenhofer; M. Krammer; D. Liko; I. Mikulec; M. Pernicka; H. Rohringer; R. Schöfbeck; J. Strauss; A. Taurok; F. Teischinger; P. Wagner; W. Waltenberger; G. Walzel; E. Widl; C.-E. Wulz; V. Mossolov; N. Shumeiko; J. Suarez Gonzalez; L. Benucci; K. Cerny; E. A. De Wolf; X. Janssen; T. Maes; L. Mucibello; S. Ochesanu; B. Roland; R. Rougny; M. Selvaggi; H. Van Haevermaet; P. Van Mechelen; N. Van Remortel; S. Beauceron; F. Blekman; S. Blyweert; J. D’Hondt; O. Devroede; R. Gonzalez Suarez; A. Kalogeropoulos; J. Maes; M. Maes; S. Tavernier; W. Van Doninck; P. Van Mulders; G. P. Van Onsem; I. Villella; O. Charaf; B. Clerbaux; G. De Lentdecker; V. Dero; A. P. R. Gay; G. H. Hammad; T. Hreus; P. E. Marage; L. Thomas; C. Vander Velde; P. Vanlaer; J. Wickens; V. Adler; S. Costantini; M. Grunewald; B. Klein; A. Marinov; J. Mccartin; D. Ryckbosch; F. Thyssen; M. Tytgat; L. Vanelderen; P. Verwilligen; S. Walsh; N. Zaganidis; S. Basegmez; G. Bruno; J. Caudron; L. Ceard; J. De Favereau De Jeneret; C. Delaere; P. Demin; D. Favart; A. Giammanco; G. Grégoire; J. Hollar; V. Lemaitre; J. Liao; O. Militaru; S. Ovyn; D. Pagano; A. Pin; K. Piotrzkowski; N. Schul; N. Beliy; T. Caebergs; E. Daubie; G. A. Alves; D. De Jesus Damiao; M. E. Pol; M. H. G. Souza; W. Carvalho; E. M. Da Costa; C. De Oliveira Martins; S. Fonseca De Souza; L. Mundim; H. Nogima; V. Oguri; W. L. Prado Da Silva; A. Santoro; S. M. Silva Do Amaral; A. Sznajder; F. Torres Da Silva De Araujo; F. A. Dias; M. A. F. Dias; T. R. Fernandez Perez Tomei; E. M. Gregores; F. Marinho; S. F. Novaes; Sandra S. Padula; N. Darmenov; L. Dimitrov; V. Genchev; P. Iaydjiev; S. Piperov; M. Rodozov; S. Stoykova; G. Sultanov; V. Tcholakov; R. Trayanov; I. Vankov; M. Dyulendarova; R. Hadjiiska; V. Kozhuharov; L. Litov; E. Marinova; M. Mateev; B. Pavlov; P. Petkov; J. G. Bian; G. M. Chen; H. S. Chen; C. H. Jiang; D. Liang; S. Liang; J. Wang; X. Wang; Z. Wang; M. Xu; M. Yang; J. Zang; Z. Zhang; Y. Ban; S. Guo; Y. Guo; W. Li; Y. Mao; S. J. Qian; H. Teng; L. Zhang; B. Zhu; W. Zou; A. Cabrera; B. Gomez Moreno; A. A. Ocampo Rios; A. F. Osorio Oliveros; J. C. Sanabria; N. Godinovic; D. Lelas; K. Lelas; R. Plestina; D. Polic; I. Puljak; Z. Antunovic; M. Dzelalija; V. Brigljevic; S. Duric; K. Kadija; S. Morovic; A. Attikis; M. Galanti; J. Mousa; C. Nicolaou; F. Ptochos; P. A. Razis; H. Rykaczewski; M. Finger; Y. Assran; M. A. Mahmoud; A. Hektor; M. Kadastik; K. Kannike; M. Müntel; M. Raidal; L. Rebane; V. Azzolini; P. Eerola; S. Czellar; J. Härkönen; A. Heikkinen; V. Karimäki; R. Kinnunen; J. Klem; M. J. Kortelainen; T. Lampén; K. Lassila-Perini; S. Lehti; T. Lindén; P. Luukka; T. Mäenpää; E. Tuominen; J. Tuominiemi; E. Tuovinen; D. Ungaro; L. Wendland; K. Banzuzi; A. Korpela; T. Tuuva; D. Sillou; M. Besancon; S. Choudhury; M. Dejardin; D. Denegri; B. Fabbro; J. L. Faure; F. Ferri; S. Ganjour; F. X. Gentit; A. Givernaud; P. Gras; G. Hamel de Monchenault; P. Jarry; E. Locci; J. Malcles; M. Marionneau; L. Millischer; J. Rander; A. Rosowsky; I. Shreyber; M. Titov; P. Verrecchia; S. Baffioni; F. Beaudette; L. Bianchini; M. Bluj; C. Broutin; P. Busson; C. Charlot; T. Dahms; L. Dobrzynski; R. Granier de Cassagnac; M. Haguenauer; P. Miné; C. Mironov; C. Ochando; P. Paganini; D. Sabes; R. Salerno; Y. Sirois; C. Thiebaux; B. Wyslouch; A. Zabi; J.-L. Agram; J. Andrea; A. Besson; D. Bloch; D. Bodin; J.-M. Brom; M. Cardaci; E. C. Chabert; C. Collard; E. Conte; F. Drouhin; C. Ferro; J.-C. Fontaine; D. Gelé; U. Goerlach; S. Greder; P. Juillot; M. Karim; A.-C. Le Bihan; Y. Mikami; P. Van Hove; F. Fassi; D. Mercier; C. Baty; N. Beaupere; M. Bedjidian; O. Bondu; G. Boudoul; D. Boumediene; H. Brun; N. Chanon; R. Chierici; D. Contardo; P. Depasse; H. El Mamouni; A. Falkiewicz; J. Fay; S. Gascon; B. Ille; T. Kurca; T. Le Grand; M. Lethuillier; L. Mirabito; S. Perries; V. Sordini; S. Tosi; Y. Tschudi; P. Verdier; H. Xiao; L. Megrelidze; V. Roinishvili; D. Lomidze; G. Anagnostou; M. Edelhoff; L. Feld; N. Heracleous; O. Hindrichs; R. Jussen; K. Klein; J. Merz; N. Mohr; A. Ostapchuk; A. Perieanu; F. Raupach; J. Sammet; S. Schael; D. Sprenger; H. Weber; M. Weber; B. Wittmer; M. Ata; W. Bender; M. Erdmann; J. Frangenheim; T. Hebbeker; A. Hinzmann; K. Hoepfner; C. Hof; T. Klimkovich; D. Klingebiel; P. Kreuzer; D. Lanske; C. Magass; G. Masetti; M. Merschmeyer; A. Meyer; P. Papacz; H. Pieta; H. Reithler; S. A. Schmitz; L. Sonnenschein; J. Steggemann; D. Teyssier; M. Bontenackels; M. Davids; M. Duda; G. Flügge; H. Geenen; M. Giffels; W. Haj Ahmad; D. Heydhausen; T. Kress; Y. Kuessel; A. Linn; A. Nowack; L. Perchalla; O. Pooth; J. Rennefeld

2011-01-01

328

Assessment of Digital Image Correlation Measurement Errors: Methodology and Results  

Microsoft Academic Search

Optical full-field measurement methods such as Digital Image Correlation (DIC) are increasingly used in the field of experimental\\u000a mechanics, but they still suffer from a lack of information about their metrological performances. To assess the performance\\u000a of DIC techniques and give some practical rules for users, a collaborative work has been carried out by the Workgroup “Metrology”\\u000a of the French

M. Bornert; F. Brémand; P. Doumalin; J.-C. Dupré; M. Fazzini; M. Grédiac; F. Hild; S. Mistou; J. Molimard; J.-J. OrteuL; L. Robert; Y. Surrel; P. Vacher; B. Wattrisse

2009-01-01

329

Tibiofemoral centroid velocity correlates more consistently with cartilage damage than does contact path length in two ovine models of stifle injury.  

PubMed

Anterior cruciate ligament (ACL) rupture and/or meniscal injury are known risk factors for post-traumatic osteoarthritis. We tested the hypothesis that increasingly abnormal tibiofemoral centroid path lengths and velocities would correlate with the severity of cartilage damage in injured sheep. Six sheep underwent combined ACL/medial collateral ligament transection (ACL/MCLx), five complete lateral meniscectomy (Mx), and four sham arthrotomy (Sham). Weighted centroids were used to estimate in vivo tibiofemoral cartilage contact path length during stance and the velocity of relative motion. Cartilage morphology was graded at dissection. Ligament transection significantly elongated plateau centroid path lengths and velocities, whereas condyle paths and velocities were reduced. Differences between plateau and femoral velocities (relative centroid velocity) were increased up to 10-fold over baseline values in the medial compartment. Reductions in Mx lateral compartment paths were significantly different from ACL/MCLx paths, but not relative to baseline or Sham values. Importantly, only centroid velocities consistently correlated with cartilage damage in either injury model, suggesting that while path length is valuable in detecting changes in the envelope of joint motion, it may average out meaningful peaks in the rate of relative motion that more closely relate to the mechanisms that might be damaging articular cartilage in these models. PMID:23832294

Beveridge, Jillian E; Heard, Bryan J; Shrive, Nigel G; Frank, Cyril B

2013-11-01

330

Analysis of Correlation between Body Length and Genetic Polymorphism for Loci ESTD1 and IDHP-3 in the Atlantic Salmon Salmo salar  

Microsoft Academic Search

Correlation between body length and characteristics of genetic polymorphism for loci Me-2, IDHP-3, ESTD-1, and AAT-2 were studied in the Atlantic salmon Salmo salar. The study was based on data on genetic variation in more than 4000 fish grown at the Kandalaksha Hatchery. Of four loci studied, loci ESTD-1 and IDHP-3 were distinguished by the fact that they can be

A. N. Evsyukov; M. V. Oficerov; I. V. Kononov

2002-01-01

331

Correlation of Sequence Block Lengths and Degree of Randomness with Melt Rheological Properties in PET\\/PEN Blends  

Microsoft Academic Search

PET\\/PEN blends were prepared over the full composition range via a melt mixing process under various processing conditions. This resulted in transesterification reactions and formation of copolymer structures with various average sequence block lengths (L?nPET L?nPET) and degree of randomness (RD) determined by 1H NMR. It was seen that with an increase in time and temperature of mixing copolymer content

Hossein Ali Khonakdar; Mahdi Golriz; Seyed-Hassan Jafari; Udo Wagenknecht

2009-01-01

332

Beta Neutrino Correlation Measurement with Trapped Radioactive Ions  

SciTech Connect

The beta-neutrino angular correlation coefficient provides a sensitive observable to search for physics beyond the standard electroweak model in nuclear beta decay. We address here the measurement of this parameter in the pure Gamow-Teller transition of {sup 6}He. A deviation from the standard model prediction would indicate the existence of tensor like couplings, possibly mediated by new bosons like leptoquarks. The aim of the LPCTrap experiment is to measure this coefficient with a statistical uncertainty of 0.5% using a novel transparent Paul trap. The status of the experiment is briefly presented along with the work in progress.

Velten, Ph.; Ban, G.; Durand, D.; Flechard, X.; Lienard, E.; Mauger, F.; Naviliat-Cuncic, O. [LPC-Caen, ENSICAEN, Universite de Caen, CNRS/IN2P3-ENSI, Caen (France); Mery, A. [CIMAP, ENSICAEN, Universite de Caen, CNRS/IN2P3-ENSI, Caen (France); Rodriguez, D. [Dep. de Fisica Atomica, Molecular y Nuclear, Facultad de Ciencias, Universitad de Granada, Granada (Spain); Thomas, J.-C. [GANIL, CEA/DSM-CNRS/IN2P3, Caen (France)

2010-04-30

333

Ternary Fission Studies by Correlation Measurements with Ternary Particles  

NASA Astrophysics Data System (ADS)

The rare ternary fission process has been studied mainly by inclusive measurements of the energy distributions and fractional yields of the light charged particles (LCPs) from fission, or by experiments on the angular and energy correlation between LCPs and fission fragments (FFs). The present contribution presents a brief overview of more elaborate correlation measurements that comprise the emission of neutrons and ? rays with LCPs and FFs, or the coincident registration of two LCPs. These measurements have permitted identification of new modes of particle-accompanied fission, such as the population of excited states in LCPs, the formation of neutron-unstable nuclei as short-lived intermediate LCPs, as well as the sequential decay of particle-unstable LCPs and quaternary fission. Furthermore, the neutron multiplicity numbers bar ? (A) and distributions of fragment masses A, measured for the ternary fission modes with various LCP isotopes, give a valuable hint of the role played by nuclear shell structure in the fission process near scission. Finally, two different hitherto unknown asymmetries in ternary ?-particle emission with respect to the fission axis, called the TRI and ROT effect, were studied in fission reactions induced by polarised cold neutrons.

Mutterer, Manfred

2011-10-01

334

Frequency of nonallelic homologous recombination is correlated with length of homology: evidence that ectopic synapsis precedes ectopic crossing-over.  

PubMed

Genomic disorders constitute a class of diseases that are associated with DNA rearrangements resulting from region-specific genome instability, that is, genome architecture incites genome instability. Nonallelic homologous recombination (NAHR) or crossing-over in meiosis between sequences that are not in allelic positions (i.e., paralogous sequences) can result in recurrent deletions or duplications causing genomic disorders. Previous studies of NAHR have focused on description of the phenomenon, but it remains unclear how NAHR occurs during meiosis and what factors determine its frequency. Here we assembled two patient cohorts with reciprocal genomic disorders; deletion associated Smith-Magenis syndrome and duplication associated Potocki-Lupski syndrome. By assessing the full spectrum of rearrangement types from the two cohorts, we find that complex rearrangements (those with more than one breakpoint) are more prevalent in copy-number gains (17.7%) than in copy-number losses (2.3%); an observation that supports a role for replicative mechanisms in complex rearrangement formation. Interestingly, for NAHR-mediated recurrent rearrangements, we show that crossover frequency is positively associated with the flanking low-copy repeat (LCR) length and inversely influenced by the inter-LCR distance. To explain this, we propose that the probability of ectopic chromosome synapsis increases with increased LCR length, and that ectopic synapsis is a necessary precursor to ectopic crossing-over. PMID:21981782

Liu, Pengfei; Lacaria, Melanie; Zhang, Feng; Withers, Marjorie; Hastings, P J; Lupski, James R

2011-10-01

335

Measurement of laminar burning speeds and Markstein lengths using a novel methodology  

Microsoft Academic Search

Three different methodologies used for the extraction of laminar information are compared and discussed. Starting from an asymptotic analysis assuming a linear relation between the propagation speed and the stretch acting on the flame front, temporal radius evolutions of spherically expanding laminar flames are postprocessed to obtain laminar burning velocities and Markstein lengths. The first methodology fits the temporal radius

Toni Tahtouh; Fabien Halter; Christine Mounaïm-Rousselle

2009-01-01

336

Effects of length and linguistic complexity on temporal acoustic measures in apraxia of speech.  

PubMed

The purpose of this study was to examine the effects of varying length and linguistic utterance types on temporal acoustic characteristics of the imitative speech of apraxic speakers. Vowel duration and two between-word segment durations were examined during the production of three response types: words, word-strings, and sentences. Three length conditions were studied in words, two length conditions for word-strings, and three length conditions for sentences, yielding eight experimental conditions. Apraxic speakers exhibited significantly longer vowel and between-word segment durations than control speakers in all conditions. Apraxic speakers consistently produced longer vowel and between-word segment durations in sentence contexts than in word contexts. Further, intrasubject and intersubject variability for between-word segment durations were substantially greater for the apraxic speakers in sentences compared to word conditions, whereas control speakers exhibited greater homogeneity in sentence production. The differences in duration and variability in sentence production versus word or word-string production imply different mechanisms for executing motor programs for varying linguistic stimuli. PMID:8898255

Strand, E A; McNeil, M R

1996-10-01

337

Measurement of helicopter rotor blade deformation using digital image correlation  

NASA Astrophysics Data System (ADS)

An experimental study on the application of the digital image correlation (DIC) technique to measure the deformation of rotating helicopter blades is described. Measurements on two different rotors of diameter 24 and 39 in., with different rotor hubs, were carried out to explore applicability of the technique over a range of scales. Commercial DIC software was synchronized with the frequency of rotation such that rotor blade images could be obtained at a constant rotor azimuth. Bending and torsion mode shapes were extracted from the data with deformation as high as 0.4 in. measured with an accuracy of 0.0038 in. This technique is very advantageous because it is noncontact, cost effective, accurate and simple to implement while yielding full-field, three-dimensional data with a high spatial resolution.

Sirohi, Jayant; Lawson, Michael S.

2012-04-01

338

Displacement measurements of highway bridges using digital image correlation methods  

NASA Astrophysics Data System (ADS)

Digital image correlation methods (DICMs) are important tools in experimental solid mechanics. DICM is becoming very versatile and cost effective due to the dramatic improvement over the digital cameras. Current study applies DICMs to displacement measurements of full-scale concrete beams. Computer programs are implemented and tested against the contact measurements using a linear variable differential transformer (LVDT). The calculated displacements agree with the LVDT measurements that the difference is mostly within 3%. The DICM programs produce similar displacement fields to those obtained using two computer codes written by other researchers. The DICM programs compute a singlepoint in merely seconds while completing the displacement calculation for a whole-field region of one mega pixels in one hour. Additional tests on the vertical displacement of a highway bridge also achieve a reasonable result which can be extended to health monitoring of bridges.

Chiang, Chih-Hung; Shih, Ming-Hsiang; Chen, Welltin; Yu, Chih-Peng

2011-08-01

339

Measurement of fluid velocity fields using digital correlation techniques  

NASA Technical Reports Server (NTRS)

A new aperiodic recording technique for measuring fluid velocity fields by digital correlation is introduced which uses a low-powered He-Ne laser, a desktop computer, and a lightly seeded fluid. In contrast to optical methods, this technique does not need to use laser light to interrogate the image pattern, so no secondary speckle is introduced. Also, the lower limit of displacement measurement is determined by the resolution of the sensor used and the magnification of the camera, and can be much lower than the speckle size, so a considerably wider range of measurement is possible than with optical processing. The technique can be completely automated and is potentially much faster than all of the optical methods currently used for flow visualization.

Matthys, Donald R.; Puliparambil, Joseph T.; Gilbert, John A.

1990-01-01

340

Improved digital image correlation for in-plane displacement measurement.  

PubMed

Electronic speckle photography (ESP) for in-plane displacement (IPD) and deformation measurements is well known with its more modern form, digital image correlation (DIC). Two speckle images of an optically rough surface before and after deformation, called reference and test images, are recorded and processed for IPD or deformation measurement of the test image with respect to the reference image. The reliability of ESP in measurements depends strongly on the postprocessing of the two images by DIC, which we have referred to as conventional DIC. In this paper, we are proposing a small but useful modification in the existing DIC methods by introducing some additional steps, which drastically improves the results obtained with the existing techniques. The modification to the conventional DIC method has been referred to as modified DIC. Computer-simulated and experimental results have been presented to validate the superiority of modified DIC over conventional DIC methods. PMID:24663278

Mudassar, Asloob Ahmad; Butt, Saira

2014-02-10

341

Measuring capital market efficiency: Global and local correlations structure  

NASA Astrophysics Data System (ADS)

We introduce a new measure for capital market efficiency. The measure takes into consideration the correlation structure of the returns (long-term and short-term memory) and local herding behavior (fractal dimension). The efficiency measure is taken as a distance from an ideal efficient market situation. The proposed methodology is applied to a portfolio of 41 stock indices. We find that the Japanese NIKKEI is the most efficient market. From a geographical point of view, the more efficient markets are dominated by the European stock indices and the less efficient markets cover mainly Latin America, Asia and Oceania. The inefficiency is mainly driven by a local herding, i.e. a low fractal dimension.

Kristoufek, Ladislav; Vosvrda, Miloslav

2013-01-01

342

Importance of Independent Measurement of Width and Length of Lateral Meniscus During Preoperative Sizing for Meniscal Allograft Transplantation  

Microsoft Academic Search

Background: Successful meniscus transplantation depends on an accurate sizing of the meniscal allograft. Although accurate sizing of the meniscal allograft is crucial during meniscus transplantation, the accuracy of meniscal measurement methods is still in debate.Purpose: This study was undertaken to evaluate the relationship between the width and length of the lateral meniscus. These anatomic dimensions were also evaluated in the

Jung-Ro Yoon; Taik-Sun Kim; Joon-Ho Wang; Ho-Hyun Yun; Hyungtae Lim; Jae-Hyuk Yang

2011-01-01

343

Measurement of the Coherent Neutron Scattering Length of 3He by Reflection from a Quartz-Liquid-Helium Interface  

NASA Astrophysics Data System (ADS)

The real part of the bound-atom coherent neutron scattering length of 3He has been measured by comparing the reflectivities of quartz-liquid-3He and quartz-liquid-4He interfaces and has been found to have the value (6.1 +/- 0.6) × 10- 13 cm.

Kitchens, T. A.; Oversluizen, T.; Passell, L.; Schermer, R. I.

1974-04-01

344

Measuring peptide mass spectrum correlation using the quantum Grover algorithm  

NASA Astrophysics Data System (ADS)

We investigated the use of the quantum Grover algorithm in the mass-spectrometry-based protein identification process. The approach coded the mass spectra on a quantum register and uses the Grover search algorithm for searching multiple solutions to find matches from a database. Measurement of the fidelity between the input and final states was used to quantify the similarity between the experimental and theoretical spectra. The optimal number of iteration is proven to be (?)/(4)(N)/(k) , where k refers to the number of marked states. We found that one iteration is sufficient for the search if we let more that 62% of the N states be marked states. By measuring the fidelity after only one iteration of Grover search, we discovered that it resembles that of the correlation-based measurement used in the existing protein identification software. We concluded that the quantum Grover algorithm can be adapted for a correlation-based mass spectra database search, provided that decoherence can be kept to a minimum.

Choo, Keng Wah

2007-03-01

345

Measuring peptide mass spectrum correlation using the quantum Grover algorithm.  

PubMed

We investigated the use of the quantum Grover algorithm in the mass-spectrometry-based protein identification process. The approach coded the mass spectra on a quantum register and uses the Grover search algorithm for searching multiple solutions to find matches from a database. Measurement of the fidelity between the input and final states was used to quantify the similarity between the experimental and theoretical spectra. The optimal number of iteration is proven to be pi/4sqrt[N/k] , where k refers to the number of marked states. We found that one iteration is sufficient for the search if we let more that 62% of the N states be marked states. By measuring the fidelity after only one iteration of Grover search, we discovered that it resembles that of the correlation-based measurement used in the existing protein identification software. We concluded that the quantum Grover algorithm can be adapted for a correlation-based mass spectra database search, provided that decoherence can be kept to a minimum. PMID:17500738

Choo, Keng Wah

2007-03-01

346

Measurements of Siple transmitter signals on the DE 1 satellite - Wave normal direction and antenna effective length  

NASA Technical Reports Server (NTRS)

A new experimental technique is developed to simultaneously measure the wave propagation direction and the effective length of a small (L value much smaller than wavelength) electric dipole antenna on a spin-stabilized satellite in the magnetosphere. The technique relies on the near simultaneous measurement of single components of the electric and magnetic fields of a coherent VLF signal injected into the medium from a ground-based source. The spin fading characteristics of the signal received by the electric dipole and the magnetic loop antenna permit the measurement of the wave normal direction assuming whistler-mode propagation. In-situ and remote measurements of the local cold plasma density are used to determine the refractive index. The wave electric field is then inferred from the wave magnetic field as measured on the loop antenna, the refractive index and the direction of propagation. Comparing this electric field with the measured voltage across the dipole antenna leads to the determination of the effective length of the receiving electric dipole. The technique is applied to data from the Dynamics Explorer 1 satellite observations of whistler mode signals injected into the magnetosphere from the Siple, Antarctica, VLF transmitter. In one case, with the measured background cold plasma density being 15 el/cu cm, the effective length of the 200 m-long electric dipole antenna is found to be 222 + or - 56 m, i.e., about twice the conventional value.

Sonwalker, V. S.; Inan, U. S.

1986-01-01

347

New Measurement of the {sup 1}S {sub 0} Neutron-Neutron Scattering Length Using the Neutron-Proton Scattering Length as a Standard  

SciTech Connect

This paper reports high-accuracy cross-section data taken for identical kinematic conditions of the neutron-proton (np) and neutron-neutron (nn) final-state interactions in the {sup 2}H( n,thinspnnp) reaction at an incident mean neutron energy of 13.0thinspthinspMeV. These data were analyzed with rigorous three-nucleon calculations to determine the {sup 1}S{sub 0} np and nn scattering lengths, a{sub np} and a{sub nn} . Our results are a{sub nn}={minus}18.7{plus_minus}0.6 fm and a{sub np}={minus}23.5{plus_minus}0.8 fm . The value obtained for a{sub nn} in the present work is in agreement with that from {pi}{sup {minus}}d measurements but disagrees with values obtained from earlier neutron-deuteron breakup studies. {copyright} {ital 1999} {ital The American Physical Society}

Gonzalez Trotter, D.E.; Salinas, F.; Chen, Q.; Crowell, A.S.; Howell, C.R.; Roper, C.D.; Tornow, W.; Walter, R.L. [Duke University and Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708 (United States)] [Duke University and Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708 (United States); Gloeckle, W. [Institut fuer Theoretische Physik, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany)] [Institut fuer Theoretische Physik, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany); Schmidt, D. [Physikalisch-Technische Bundesanstalt, D-38116 Braunschweig (Germany)] [Physikalisch-Technische Bundesanstalt, D-38116 Braunschweig (Germany); Slaus, I. [Rudjer Boskovic Institute, Zagreb (Croatia)] [Rudjer Boskovic Institute, Zagreb (Croatia); Tang, H.; Zhou, Z. [Chinese Institute for Atomic Energy, Beijing, People`s Republic of (China)] [Chinese Institute for Atomic Energy, Beijing, People`s Republic of (China); Witala, H. [Institute of Physics, Jagellonian University, PL-30059 Cracow (Poland)] [Institute of Physics, Jagellonian University, PL-30059 Cracow (Poland)

1999-11-01

348

Heme Carbonyls: Environmental Effects on ?C–O and Fe-C/C-O Bond Length Correlations  

PubMed Central

The synthesis and characterization of four low-spin (carbonyl)iron(II) tetraphenylporphyrinates, [Fe(TPP)(CO)(L)], where L = 1-methylimidazole, 2-methylimidazole, 1,2-dimethylimidazole (unsolvated) and 1,2-dimethylimidazole (toluene solvate) are reported. The complexes show nearly the same value of ?C–O in toluene solution (1969–72 cm?1) but a large range of CO stretching frequencies in the solid-state (1926–1968 cm?1). The large solid-state variation results from CO interactions in the solid-state as shown by an examination of the crystal structures of the four complexes. The high precision of the four structures obtained allows us to make a number of structural and spectroscopic correlations that describe the Fe–C–O and NIm–Fe–CO units. The values of ?C–O and the Fe–C and C–O bond distances are strongly correlated and provide a structural as well as a spectroscopic correlation of the ? back-bonding model. The interactions of CO described are closely related to the large range of CO stretching frequencies observed in heme proteins and specific interactions observed in carbonylmyoglobin (MbCO).

Silvernail, Nathan J.; Roth, Arne; Noll, Bruce C.; Scheidt, W. Robert; Schulz, Charles E.

2006-01-01

349

Finger Length  

NSDL National Science Digital Library

This Science Update explores male agression patterns and their correlation to pre-natal testosterone exposure. Although life experience plays a huge role in shaping who we are, the foundations of our personality begin in the womb. One recent study looks to finger length for signs of a man's pre-natal exposure to testosterone.n women, the index and ring finger are roughly equal in length. But in most men, the ring finger is longer. That's a result of fetal exposure to testosterone. Psychologists Alison Bailey and Pete Hurd, of the University of Alberta in Canada, studied these finger ratios in male college students. And they found that men with more dramatic differences tended to be more aggressive. Additional links to resources are given for further inquiry.

American Association for the Advancement of Science (;)

2005-03-28

350

Quantum discord: a measure of the quantumness of correlations.  

PubMed

Two classically identical expressions for the mutual information generally differ when the systems involved are quantum. This difference defines the quantum discord. It can be used as a measure of the quantumness of correlations. Separability of the density matrix describing a pair of systems does not guarantee vanishing of the discord, thus showing that absence of entanglement does not imply classicality. We relate this to the quantum superposition principle, and consider the vanishing of discord as a criterion for the preferred effectively classical states of a system, i.e., the pointer states. PMID:11800986

Ollivier, Harold; Zurek, Wojciech H

2002-01-01

351

Some measurements of time and space correlation in wind tunnel  

NASA Technical Reports Server (NTRS)

Results are presented of research obtained by means of an apparatus for measurement of time and space correlation and of a spectral analyzer in the study of the longitudinal component of turbulence velocities in a wind tunnel downstream of a grid of meshes. Application to the case of a flat-plate boundary layer is illustrated. These researches were made at the Laboratoire de Mecanique de l'Atmosphere de l'I.M.F.M. for the O.N.E.R.A.

Favre, A; Gaviglio, J; Dumas, R

1955-01-01

352

Surface energy of silicas, grafted with alkyl chains of increasing lengths, as measured by contact angle techniques  

SciTech Connect

Silica, modified by esterification with linear alcohols having between 1 and 20 carbon atoms, is compacted into smooth discs. Their surface polarity, measured by contact angle techniques, decreases with increasing surface coverage and chain length of the grafts. For the longer chains, the surface energy of the grafted silicas reaches a value close to the one of poly(ethylene). The spreading pressures of water on the modified silicas were measured either by contact angle or vapor adsorption techniques. 13 references.

Kessaissia, Z. Papirer, E.; Donnet, J.B.

1981-08-01

353

A new measurement method of the delay line length in the X-band delay line distribution system (DLDS)  

Microsoft Academic Search

In order to control the driving RF phase at the input of the accelerating structure of X-band linear collider main linacs, it is necessary to measure the length of the long TE01 mode delay lines of 40-80 m. A new measurement scheme by using the low frequency resonant mode of the TE01 mode delay line was proposed. The delay lines

F. Tamura; H. Mizuno

1997-01-01

354

The Effect of Error Correlation on Interfactor Correlation in Psychometric Measurement  

ERIC Educational Resources Information Center

This article shows how interfactor correlation is affected by error correlations. Theoretical and practical justifications for error correlations are given, and a new equivalence class of models is presented to explain the relationship between interfactor correlation and error correlations. The class allows simple, parsimonious modeling of error…

Westfall, Peter H.; Henning, Kevin S. S.; Howell, Roy D.

2012-01-01

355

Multifunctional fluorescence correlation microscope for intracellular and microfluidic measurements.  

PubMed

A modified fluorescence correlation microscope (FCM) was built on a commercial confocal laser scanning microscope (CLSM) by adding two sensitive detectors to perform fluorescence correlation spectroscopy (FCS). A single pinhole for both imaging and spectroscopy and a simple slider switch between the two modes thus facilitate the accurate positioning of the FCS observation volume after the confocal image acquisition. Due to the use of a single pinhole for CLSM and FCS the identity of imaged and spectroscopically observed positions is guaranteed. The presented FCM system has the capability to position the FCS observation volume at any point within the inner 30% of the field of view without loss in performance and in the inner 60% of the field of view with changes of FCS parameters of less than 10%. A single pinhole scheme for spatial fluorescence cross correlation spectroscopy performed on the FCM system is proposed to determine microfluidic flow angles. To show the applicability and versatility of the system, we measured the translational diffusion coefficients on the upper and lower membranes of Chinese hamster ovary cells. Two-photon excitation FCS was also realized by coupling a pulsed Ti: sapphire laser into the microscope and used for flow direction characterization in microchannels. PMID:17552829

Pan, Xiaotao; Foo, Willy; Lim, Wanrong; Fok, Marcus H Y; Liu, Ping; Yu, Hanry; Maruyama, Ichiro; Wohland, Thorsten

2007-05-01

356

Estimate of the energy spread in a booster cycle via the bunch length measurement  

SciTech Connect

It is important for us to obtain the information of energy spread vs. time in a Booster cycle via the same beam event, for the purpose of minimizing the error caused by the cycle-to-cycle fluctuation. The bunch length (BL) can be extracted from the resistive wall signal (RWS) at different times of a Booster cycle, and from which the energy spread can be estimated.

Yang, Xi; /Fermilab

2004-11-01

357

Water Velocity Measurement on an Extended-Length Submerged Bar Screen at John Day Dam  

SciTech Connect

This report describes a study of water velocity around an extended-length submerged bar screen (ESBS) at John Day Dam. The study was conducted for the U.S. Army Corps of Engineers by AScI Corporation and MEVATEC Corporation in March of 2000. This report was prepared by Pacific Northwest National Laboratory. ESBS are being studied as one method for diverting juvenile migrating fish from the dam's turbine intakes into the gate well and through the juvenile fish bypass channels.

Weiland, Mark A.; Escher, Charles

2001-04-02

358

ABSOLUTE BUNCH LENGTH MEASUREMENTS AT THE ALS BY INCOHERENTSYNCHROTRON RADIATION FLUCTUATION ANALYSIS  

SciTech Connect

By analysing the pulse to pulse intensity fluctuations ofthe radiation emitted by a charge particle in the incoherent part of thespectrum, it is possible to extract information about the spatialdistribution of the beam. At the Advanced Light Source (ALS) of theLawrence Berkeley National Laboratory, we have developed and tested asimple scheme based on this principle that allows for the absolutemeasurement of the bunch length. A description of the method and theexperimental results are presented.

Sannibale, Fernando; Zolotorev, Max S.; Filippetto, Daniele; Stupakov, Gennady V.

2007-06-22

359

Correlated speckle noise in white-light interferometry: theoretical analysis of measurement uncertainty  

SciTech Connect

The partial coherent illumination of the specimen, which is required for white-light interferometric measurements of optically rough surfaces, directly leads to speckle. The electric field of such speckle patterns strongly fluctuates in amplitude and phase. This spatially correlated noise influences the accuracy of the measuring device. Although a variety of noise sources in white-light interferometry has been studied in recent years, they do not account for spatial correlation and, hence, they cannot be applied to speckle noise. Thus, we derive a new model enabling quantitative predictions for measurement uncertainty caused by speckle. The model reveals that the accuracy can be attributed mainly to the degree of spatial correlation, i.e., the average size of a speckle, and to the coherence length of the light source. The same parameters define the signal-to-noise ratio in the spectral domain. The model helps to design filter functions that are perfectly adapted to the noise characteristics of the respective device, thus improving the accuracy of postprocessing algorithms for envelope detection. The derived expressions are also compared to numerical simulations and experimental data of two different types of interferometers. These results are a first validation of the theoretical considerations of this article.

Hering, Marco; Koerner, Klaus; Jaehne, Bernd

2009-01-20

360

Image correlation spectroscopy for measurements of particle densities and colocalization.  

PubMed

Cells interact with their environment through receptor proteins expressed at their plasma membrane, and protein-protein interactions govern the transduction of signals across the membrane into the cell. Therefore, the ability to measure receptor densities and protein colocalization within the membrane of intact cells is of paramount importance. This unit describes a technique to extract these parameters from fluorescence microscopy images obtained using a commercial confocal laser scanning microscope (CLSM) and other similar types of microscopes. It is based on the analysis of spatial fluorescence intensity fluctuations in the images, which can then be related to particle density and aggregation state via calculation of a spatial autocorrelation function, or used to measure particle colocalization via calculation of a spatial cross-correlation function from dual-color images of proteins tagged with two different fluorophores and imaged in two detection channels. These parameters offer key insights on the interaction of the cell with its environment. PMID:23728747

Rappaz, Benjamin; Wiseman, Paul W

2013-06-01

361

openBEB: open biological experiment browser for correlative measurements  

PubMed Central

Background New experimental methods must be developed to study interaction networks in systems biology. To reduce biological noise, individual subjects, such as single cells, should be analyzed using high throughput approaches. The measurement of several correlative physical properties would further improve data consistency. Accordingly, a considerable quantity of data must be acquired, correlated, catalogued and stored in a database for subsequent analysis. Results We have developed openBEB (open Biological Experiment Browser), a software framework for data acquisition, coordination, annotation and synchronization with database solutions such as openBIS. OpenBEB consists of two main parts: A core program and a plug-in manager. Whereas the data-type independent core of openBEB maintains a local container of raw-data and metadata and provides annotation and data management tools, all data-specific tasks are performed by plug-ins. The open architecture of openBEB enables the fast integration of plug-ins, e.g., for data acquisition or visualization. A macro-interpreter allows the automation and coordination of the different modules. An update and deployment mechanism keeps the core program, the plug-ins and the metadata definition files in sync with a central repository. Conclusions The versatility, the simple deployment and update mechanism, and the scalability in terms of module integration offered by openBEB make this software interesting for a large scientific community. OpenBEB targets three types of researcher, ideally working closely together: (i) Engineers and scientists developing new methods and instruments, e.g., for systems-biology, (ii) scientists performing biological experiments, (iii) theoreticians and mathematicians analyzing data. The design of openBEB enables the rapid development of plug-ins, which will inherently benefit from the “house keeping” abilities of the core program. We report the use of openBEB to combine live cell microscopy, microfluidic control and visual proteomics. In this example, measurements from diverse complementary techniques are combined and correlated.

2014-01-01

362

Measurement of Attenuation Length for Radio Wave in Natural Rock Salt Samples Concerning Ultra High Energy Neutrino Detection  

NASA Astrophysics Data System (ADS)

Ultra high energy (UHE) neutrinos with the energy larger than 1015 eV, surely arrive at the earth with Greisen, Zatsepin, Kuz'min (GZK) effect, though the rate is very few. The rare call requires us to utilize a large mass (>10 Gton) of detection medium. UHE neutrino generates a huge number of unpaired electrons in rock salt. They would emit sensible radio wave by coherent Cherenkov (Askar'yan) effect. The longer attenuation length of radio wave in rock salt reduces the number of antennas required. Several rock salt samples including synthesized one are measured in attenuation length for radio wave transmission at 0.3 and 1.0 GHz. Some show attenuation length larger than 300 m, which indicate a possibility for constructing a salt neutrino detector.

Chiba, Masami; Watanabe, Yusuke; Yasuda, Osamu; Kamijo, Toshio; Chikashige, Yuichi; Kon, Tadashi; Amano, Akio; Takeoka, Yosito; Shimizu, Yutaka; Mori, Satoshi; Ninomiya, Sosuke

363

Normalized Movement Quality Measures for Therapeutic Robots Strongly Correlate With Clinical Motor Impairment Measures  

Microsoft Academic Search

In this paper, we analyze the correlations between four clinical measures (Fugl-Meyer upper extremity scale, Motor Activity Log, Action Research Arm Test, and Jebsen-Taylor Hand Function Test) and four robotic measures (smoothness of movement, trajectory error, average number of target hits per minute, and mean tangential speed), used to assess motor recovery. Data were gathered as part of a hybrid

Ozkan Celik; Marcia K. O'Malley; Corwin Boake; Harvey S. Levin; Nuray Yozbatiran; Timothy A. Reistetter

2010-01-01

364

Measurement of two-point two-velocity correlation functions in the ion phase-space  

NASA Astrophysics Data System (ADS)

Using two single frequency tunable lasers we generalize the technique used previously to measure two-point correlation functions to allow two different selected velocities as well. A steady-state singly-ionized Argon plasma with density 10^9 cm-3, electron temperature of 2 eV, and ion temperature of 0.1 eV in a uniformly magnetized plasma cylinder is produced using a CW radio-frequency source. The plasma column is 10 cm in diameter and the main chamber is 200 cm in length. The measurements concern the low-frequency electrostatic fluctuations that occur naturally near the electron drift frequency driven by the radial electron temperature gradient. Two independent LIF systems, with detection systems on movable carriages, are scanned using computer-controlled stepper motors. One system involves a Argon-ion pumped single-frequency dye laser at 611nm with detection at 461 nm. The second system uses a single-frequency tunable diode laser at 668nm with detection at 443nm. By looking at cross-correlation between the two detection systems it is a measurement of is realized. We will describe the tests and validations used to rule out instrumental effects on the measurement and compare the results to previous measurements of made using a single laser beam.

Skiff, Fred

2008-11-01

365

Accurate measurement of curvilinear shapes by Virtual Image Correlation  

NASA Astrophysics Data System (ADS)

The proposed method allows the detection and the measurement, in the sense of metrology, of smooth elongated curvilinear shapes. Such measurements are required in many fields of physics, for example: mechanical engineering, biology or medicine (deflection of beams, fibers or filaments), fluid mechanics or chemistry (detection of fronts). Contrary to actual methods, the result is given in an analytical form of class C? (and not a finite set of locations or pixels) thus curvatures and slopes, often of great interest in science, are given with good confidence. The proposed Virtual Image Correlation (VIC) method uses a virtual beam, an image which consists in a lateral expansion of the curve with a bell-shaped gray level. This figure is deformed until it fits the best the physical image with a method issued from the Digital Image Correlation method in use in solid mechanics. The precision of the identification is studied in a benchmark and successfully compared to two state-of-the-art methods. Three practical examples are given: a bar bending under its own weight, a thin fiber transported by a flow within a fracture and a thermal front. The first allows a comparison with theoretical solution, the second shows the ability of the method to deal with complex shapes and crossings and the third deals with ill-defined image.

Semin, B.; Auradou, H.; François, M. L. M.

2011-10-01

366

A method of a repetitive sampling measurement for OTDR considering a ghost effect to a short-range measurement with a short-length fiber  

Microsoft Academic Search

This paper discusses implementations of a repetitive sampling measurement for OTDR considering ghost effect for short period measurement with a short-length fiber. Repetitive sampling is done to acquire higher equivalent sampling rate with a low sampling clock in the data acquisition. However, the repetitive sampling can cause misalignment of ghost reflection which produces a distortion. This study analyzes the effect

Taeyeon Lee; Ealgoo Kim; Jaehong Park

2005-01-01

367

Electric-field-dependent dielectric response in the de Vries-type smectic- A* phase possessing local orientational order with nanoscale correlation length  

NASA Astrophysics Data System (ADS)

The dielectric strength is shown to increase and the relaxation frequency to decrease for a large temperature range up to a certain value of the electric field in the smectic- A* phase. This behavior contrasts to that observed in a conventional smectic- A* , but can be explained in terms of de Vries scenerio. On assuming the reorientation of the molecular dipoles with electric field to be of the Langevin type in the de Vries smectic- A* , we find that around 1300molecules , corresponding to a minimum correlation length of ???45nm in a single layer cooperatively respond to the applied field.

Manna, U.; Song, Jang-Kun; Vij, J. K.; Naciri, J.

2008-10-01

368

Recent results and prospects for correlation ECE measurements on TCV  

NASA Astrophysics Data System (ADS)

The Tokamak a Configuration Variable (TCV) has a two channel correlation electron cyclotron emission (CECE) radiometer with a line of sight perpendicular to the magnetic field. The antenna pattern of this radiometer limits resolution to k? < 112 m-1 or k??s < 0.3 at 500 kHz. It can access the region with minor radius ?vol < 0.7. A series of measurements has been made of the turbulence spectra at positive and negative triangularity and as a function of collisionality. Also, a series of measurements has been made as a function of poloidal angle, by varying the plasma vertical position with respect to the antenna, the measurements being made on the same flux surface. It is planned to extensively upgrade the diagnostic by integrating four more channels and acquiring a new front-end for the radiometer. This upgrade should reduce the required number of shots for a radial scan by a factor four and improve the signal-to-noise ratio. It is also planned to use a high gain antenna that will extend access to k? < 174m-1 or k??s < 0.5 at 500 kHz. The present system, measurements and the upgrade are described in this paper.

Porte, L.; Coda, S.; Goodman, T. P.; Pochelon, A.; Udintsev, V. S.; Vuille, V.

2012-09-01

369

Atmospheric lateral and longitudinal turbulent length scales (measured at 600 to 800 meters above grade level)  

NASA Technical Reports Server (NTRS)

NASA's Airborne Doppler Lidar System has been used to obtain a detailed 'instantaneous' mapping of horizontal spatial wind fields at 600-800 m elevations on the east side of the San Gorgonio Pass in California, in the form of checkerboard-fashion horizontal wind vectors spaced at 300 m intervals along and normal to the flight path. Spatial autocorrelations for the lateral and longitudinal components are ensemble-averaged, and integral turbulent length scales are computed for the wind fields' longitudinal and lateral directions. The flow in the region studied does not appear to be isotropic.

Cliff, W. C.; Skarda, J. R.

1987-01-01

370

Tunable non-local entanglement of electrons probed by noise cross-correlation measurement  

NASA Astrophysics Data System (ADS)

Nonlocal entanglement is crucial for quantum information processes. While nonlocal entanglement has been realized for photons, it is much more difficult to demonstrate for electrons. One approach that has been proposed is to use hybrid superconducting/normal-metal devices. When the distance between two normal-metal electrodes connected to a superconductor is comparable to the superconducting coherence length, theory predicts that two electrons in the normal-metal electrodes with opposite spin are entangled by Cooper pairs, leading to non-local entanglement of electrons. Such entanglement can be understood by a non-local process called crossed Andreev reflection (CAR), in which a Cooper pair splits into two coherent electrons with one in each normal-metal electrode, generating instantaneous current of the same sign, and inducing a positive current correlation. Experimentally, CAR is indicated by a negative non-local resistance. However, another non-local process, elastic cotunneling (EC), in which one electron tunnels through the superconductor from one normal-metal electrode to the other, contributes to a positive non-local resistance that cancels the contribution due to CAR, preventing us from measuring and control of the CAR component. Fortunately, EC leads to a negative current correlation with bias dependence different from that of CAR. Thus, noise correlation measurement is expected to be able to distinguish these two non-local processes. By cross-correlation measurements as well as measurements of the local and nonlocal resistance, we present here experimental evidence showing that by independently controlling the energy of electrons at the superconductor/normal-metal interfaces, nonlocal Andreev reflection, the signature of spin-entanglement, can be maximized, qualitatively in agreement with theoretical predication.

Wei, Jian

2010-03-01

371

A new Coulomb correction method for Bose-Einstein correlations, based on the $\\\\pi^+\\\\pi^-$ correlation measurements  

Microsoft Academic Search

We present the measured correlation functions for $\\\\pi^+\\\\pi^-$, $\\\\pi^-\\\\pi^-$ and $\\\\pi^+\\\\pi^+$ pairs in central S+Ag collisions at 200 GeV per nucleon. The Gamov function, which has been traditionally used to correct the correlation functions of charged pions for the Coulomb interaction, is found to be inconsistent with all measured correlation functions. Certain problems which have been dominating the systematic uncertainty

J. Bartke; H. Bialkowska; R. Bock; D. Brinkmann; R. Brockmann; P. Chan; I. Derado; B. Eberlein; V. Eckardt; J. Eschke; D. Ferenc; B. Fleischmann; P. Foka; P. Freund; M. Fuchs; M. Hoffmann; P. Jacobs; S. Kabana; K. Kadija; J. Kosiec; M. Kowalski; M. Lahanas; A. Ljubi; S. Margetis; R. Morse; E. Nappi; G. Odyniec; A. Petridis; A. Piper; F. Posa; W. Rauch; R. Renfordt; W. Retyk; G. Roland; H. Rothard; K. Runge; A. Sandoval; J. Schambach; N. Schmitz; E. Schmoetten; I. Schneider; R. Sendelbach; P. Seyboth; J. Seyerlein; E. Skrzypczak; P. Stefansky; L. Teitelbaum; S. Tonse; G. Vasileiadis; M. Vassiliou; S. Wenig; M. Wensveen; B. Wosiek

1997-01-01

372

Measurement of laminar burning speeds and Markstein lengths using a novel methodology  

SciTech Connect

Three different methodologies used for the extraction of laminar information are compared and discussed. Starting from an asymptotic analysis assuming a linear relation between the propagation speed and the stretch acting on the flame front, temporal radius evolutions of spherically expanding laminar flames are postprocessed to obtain laminar burning velocities and Markstein lengths. The first methodology fits the temporal radius evolution with a polynomial function, while the new methodology proposed uses the exact solution of the linear relation linking the flame speed and the stretch as a fit. The last methodology consists in an analytical resolution of the problem. To test the different methodologies, experiments were carried out in a stainless steel combustion chamber with methane/air mixtures at atmospheric pressure and ambient temperature. The equivalence ratio was varied from 0.55 to 1.3. The classical shadowgraph technique was used to detect the reaction zone. The new methodology has proven to be the most robust and provides the most accurate results, while the polynomial methodology induces some errors due to the differentiation process. As original radii are used in the analytical methodology, it is more affected by the experimental radius determination. Finally, laminar burning velocity and Markstein length values determined with the new methodology are compared with results reported in the literature. (author)

Tahtouh, Toni; Halter, Fabien; Mounaim-Rousselle, Christine [Institut PRISME, Universite d'Orleans, 8 rue Leonard de Vinci-45072, Orleans Cedex 2 (France)

2009-09-15

373

A volumetric approach to path-length measurements is essential when treating radiotherapy with modulated beams.  

PubMed

The established dosimetric benefits of intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy have lead to their increased use in prostate radiotherapy. Complimenting these techniques, volumetric image guidance has supported increased positional accuracy. In addition, 3-dimensional image guidance has also allowed for assessment of potential dosimetric variation that can be attributed to a deformation of either internal or external structures, such as rectal distension or body contour. Compounding these issues is the variation of tissue density through which the new field position passes and also the variation of dose across a modulated beam. Despite the growing level of interest in this area, there are only a limited number of articles that examine the effect of a variation in beam path length, particularly across a modulated field. IMRT and volumetric-modulated radiation therapy (VMAT) fields are dynamic in nature, and the dose gradient within these fields is variable. Assessment of variation of path length away from the beam?s central axis and across the entire field is vital where there is considerable variation of dose within the field, such as IMRT and VMAT. In these cases, reliance on the traditional central axis to focus skin distances is no longer appropriate. This article discusses these more subtle challenges that may have a significant clinical effect if left unrecognized and undervalued. PMID:24630910

Forde, Elizabeth; Booth, Jeremy; Leech, Michelle

2014-01-01

374

LIGHT SOURCE: RF deflecting cavity for bunch length measurement in Tsinghua Thomson scattering X-ray source  

NASA Astrophysics Data System (ADS)

An RF deflecting cavity used for bunch length measurement has been designed and fabricated at Tsinghua University for the Thomson Scattering X-Ray Source. The cavity is a 2856 MHz, ?-mode, 3-cell standing-wave cavity, to diagnose the 3.5 MeV beam produced by photocathode electron gun. With a larger power source, the same cavity will again be used to measure the accelerated beam with energy of 50 MeV before colliding with the laser pulse. The RF design using MAFIA for both the cavity shape and the power coupler is reviewed, followed by presenting the fabrication procedure and bench measurement results of two cavities.

Shi, Jia-Ru; Chen, Huai-Bi; Tang, Chuan-Xiang; Huang, Wen-Hui; Du, Ying-Chao; Zheng, Shu-Xin; Ren, Li

2009-06-01

375

Measurements of the effect of free-stream turbulence length scale on heat transfer  

Microsoft Academic Search

The effects of free-stream turbulence scale on heat transfer through a turbulent flat plate boundary layer have been measured. A variety of turbulence spectra were produced by parallel bar grids. The design of these was guided by previous measurements of combustion chamber turbulence. Heat transfer was measured transiently using thin film gauges. The heat transfer to the plate was found

R. W. Moss; M. L. G. Oldfield

1992-01-01

376

Impulsive noise of printers: measurement metrics and their subjective correlation  

NASA Astrophysics Data System (ADS)

In the office and home computing environments, printer impulsive noise has become a significant contributor to user perceived quality or lack thereof, and can affect the user's comfort level and ability to concentrate. Understanding and quantifying meaningful metrics for printer impulsivity is becoming an increasingly important goal for printer manufacturers. Several methods exist in international standards for measuring the impulsivity of noise. For information technology equipment (ITE), the method for detection of impulsive noise is provided in ECMA-74 and ISO 7779. However, there is a general acknowledgement that the current standard method of determining impulsivity by simply measuring A-weighted sound pressure level (SPL) with the impulsive time weighting, I, applied is inadequate to characterize impulsive noise and ultimately to predict user satisfaction and acceptance. In recent years, there has been a variety of new measurement methods evaluated for impulsive noise for both environmental and machinery noise. This paper reviews several of the available metrics, applies the metrics to several printer impulsive noise sources, and makes an initial assessment of their correlation to the subjective impressions of users. It is a review and continuation of the work presented at InterNoise 2005 (Baird, Bray, and Otto).

Baird, Terrence; Otto, Norman; Bray, Wade; Stephan, Mike

2005-09-01

377

Viscosity Measurements and Correlation of the Squalane + CO2 Mixture  

NASA Astrophysics Data System (ADS)

Experimental results for the viscosity of squalane + CO2 mixtures are reported. The viscosities were measured using a rolling ball viscometer. The experimental temperatures were 293.15, 313.15, 333.15, and 353.15 K, and pressures were 10.0, 15.0, and 20.0 MPa. The CO2 mole fraction of the mixtures varied from 0 to 0.417. The experimental uncertainties in viscosity were estimated to be within ±3.0%. The viscosity of the mixtures decreased with an increase in the CO2 mole fraction. The experimental data were compared with predictions from the Grunberg-Nissan and McAllister equations, which correlated the experimental data with maximum deviations of 10 and 8.7%, respectively.

Tomida, D.; Kumagai, A.; Yokoyama, C.

2007-02-01

378

Phase-field model for front propagation in a temperature gradient: Selection and competition between the correlation and the thermal lengths  

NASA Astrophysics Data System (ADS)

A phase-field model is presented to study the propagation and the selection of a front in directional growth. The phase transition can be first or second order and is described by a nonconserved order parameter. In general, the thermal length lu (inversely proportional to the temperature gradient) is much larger than the correlation length l?, which gives the width of the front, and there is no direct competition between them (?=l?/lu?1). In this paper, we consider a situation where these two lengths can be of the same order of magnitude (?=l?/lu close to 1). This happens in liquid crystals at the nematic-cholesteric phase transition. The problem of the front selection is solved theoretically by first performing an asymptotic analysis of the governing equations in the limit ??0, and then by solving the equations numerically. The main result is that the front is selected in a single way (no continuum of solutions) as long as ??0, whatever the velocity and the order of the phase transition. Finally, we show that the order parameter profile and the front temperature can change significantly when ? approaches 1.

Popa-Nita, V.; Oswald, P.

2002-12-01

379

Effect of tensile stress on the phase transition in Cu(2,5-dimethyl-N,N?-dicyanoquinonediimine) 2—correlation of crystal length and conductivity  

Microsoft Academic Search

Using a new interferometric mechanical set up, we have measured the elongation and the resistance of deuterated Cu(2,5-dimethyl-dicyanoquinonediimine)2 crystals along the c-direction as functions of temperature. The crystal length l decreases with dl(l · dT) = 1.1 · 10?4K at about 300 K to exhibit a minimum at 50 K. Below 50 K, l increases at further cooling. At the

H. Hild; J. U. von Schütz; H. Wachtel

1997-01-01

380

Q-FISH Measurement of Hepatocyte Telomere Lengths in Donor Liver and Graft after Pediatric Living-Donor Liver Transplantation: Donor Age Affects Telomere Length Sustainability  

PubMed Central

Along with the increasing need for living-donor liver transplantation (LDLT), the issue of organ shortage has become a serious problem. Therefore, the use of organs from elderly donors has been increasing. While the short-term results of LDLT have greatly improved, problems affecting the long-term outcome of transplant patients remain unsolved. Furthermore, since contradictory data have been reported with regard to the relationship between donor age and LT/LDLT outcome, the question of whether the use of elderly donors influences the long-term outcome of a graft after LT/LDLT remains unsettled. To address whether hepatocyte telomere length reflects the outcome of LDLT, we analyzed the telomere lengths of hepatocytes in informative biopsy samples from 12 paired donors and recipients (grafts) of pediatric LDLT more than 5 years after adult-to-child LDLT because of primary biliary atresia, using quantitative fluorescence in situ hybridization (Q-FISH). The telomere lengths in the paired samples showed a robust relationship between the donor and grafted hepatocytes (r?=?0.765, p?=?0.0038), demonstrating the feasibility of our Q-FISH method for cell-specific evaluation. While 8 pairs showed no significant difference between the telomere lengths for the donor and the recipient, the other 4 pairs showed significantly shorter telomeres in the recipient than in the donor. Multiple regression analysis revealed that the donors in the latter group were older than those in the former (p?=?0.001). Despite the small number of subjects, this pilot study indicates that donor age is a crucial factor affecting telomere length sustainability in hepatocytes after pediatric LDLT, and that the telomeres in grafted livers may be elongated somewhat longer when the grafts are immunologically well controlled.

Kawano, Youichi; Ishikawa, Naoshi; Aida, Junko; Sanada, Yukihiro; Izumiyama-Shimomura, Naotaka; Nakamura, Ken-ichi; Poon, Steven S. S.; Matsumoto, Koshi; Mizuta, Koichi; Uchida, Eiji; Tajiri, Takashi; Kawarasaki, Hideo; Takubo, Kaiyo

2014-01-01

381

Q-FISH Measurement of Hepatocyte Telomere Lengths in Donor Liver and Graft after Pediatric Living-Donor Liver Transplantation: Donor Age Affects Telomere Length Sustainability.  

PubMed

Along with the increasing need for living-donor liver transplantation (LDLT), the issue of organ shortage has become a serious problem. Therefore, the use of organs from elderly donors has been increasing. While the short-term results of LDLT have greatly improved, problems affecting the long-term outcome of transplant patients remain unsolved. Furthermore, since contradictory data have been reported with regard to the relationship between donor age and LT/LDLT outcome, the question of whether the use of elderly donors influences the long-term outcome of a graft after LT/LDLT remains unsettled. To address whether hepatocyte telomere length reflects the outcome of LDLT, we analyzed the telomere lengths of hepatocytes in informative biopsy samples from 12 paired donors and recipients (grafts) of pediatric LDLT more than 5 years after adult-to-child LDLT because of primary biliary atresia, using quantitative fluorescence in situ hybridization (Q-FISH). The telomere lengths in the paired samples showed a robust relationship between the donor and grafted hepatocytes (r?=?0.765, p?=?0.0038), demonstrating the feasibility of our Q-FISH method for cell-specific evaluation. While 8 pairs showed no significant difference between the telomere lengths for the donor and the recipient, the other 4 pairs showed significantly shorter telomeres in the recipient than in the donor. Multiple regression analysis revealed that the donors in the latter group were older than those in the former (p?=?0.001). Despite the small number of subjects, this pilot study indicates that donor age is a crucial factor affecting telomere length sustainability in hepatocytes after pediatric LDLT, and that the telomeres in grafted livers may be elongated somewhat longer when the grafts are immunologically well controlled. PMID:24727734

Kawano, Youichi; Ishikawa, Naoshi; Aida, Junko; Sanada, Yukihiro; Izumiyama-Shimomura, Naotaka; Nakamura, Ken-Ichi; Poon, Steven S S; Matsumoto, Koshi; Mizuta, Koichi; Uchida, Eiji; Tajiri, Takashi; Kawarasaki, Hideo; Takubo, Kaiyo

2014-01-01

382

Measurement of diffusion in articular cartilage using fluorescence correlation spectroscopy  

PubMed Central

Background Fluorescence correlation spectroscopy (FCS) provides information about translational diffusion of fluorescent molecules in tiny detection volumes at the single-molecule level. In normal states, cartilage tissue lacks vascularity, so chondrocyte metabolism depends on diffusion for molecular exchanges. The abundant extracellular matrix (ECM) of cartilage is maintained by a limited number of chondrocytes. ECM plays an important role in the regulation of chondrocyte functions. In this study, FCS was used to measure diffusion behaviors of albumin, the major protein of the intra-articular space, using normal and degenerated cartilage. Preliminary investigation of fluorescence dyes including Alexa 488, Rhodamine 6G and Rhodamine 123 was conducted to evaluate their properties in cartilage. Results The results indicate that the diffusion behaviors of fluorescently lableded albumin can be observed using FCS in both normal and chemically degenerated cartilage. Conclusions This work demonstrates the capability of FCS for direct measurement of diffusion in cartilaginous ECM. When the diffusion characteristics of fluorescent probes in ECM are clarified using FCS evaluation, FCS will be applicable as a method for early diagnosis of osteoarthritis, which is accompanied by increased abnormalities of ECM and also as tool for evaluating bio-engineered artificial cartilage for autologous chondrocyte implantation.

2011-01-01

383

Theoretical predictions for spatial covariance of the electroencephalographic signal during the anesthetic-induced phase transition: Increased correlation length and emergence of spatial self-organization  

NASA Astrophysics Data System (ADS)

In a recent series of papers, the authors have developed a stochastic theory to describe the electrical response of a spatially homogeneous cerebral cortex to infusion of a general anesthetic agent. We showed that by modeling the GABAergic (propofol-like) drug effect as a prolongation of the inhibitory postsynaptic impulse response, we obtain a prediction that there will be a hysteretically separated pair of first-order phase transitions in the population-average excitatory soma voltage, the first occurring at the point of induction of unconsciousness, and the second at the point of emergence from unconsciousness. In the present paper we generalize our earlier “zero-dimensional” homogeneous cortex to a one-dimensional (1D) line of cortical “mass,” thus allowing for the possibility of spatial inhomogeneities in neural activity. Following the spirit of our earlier adiabatic (“slow membrane”) philosophy, we impose a spatioadiabatic approximation that permits us to compute analytic expressions for changes in EEG (electroencephalographic) correlation length and EEG spatial covariance as a function of anesthetic effect. We establish that the correlation length of the EEG fluctuations is expected to increase at the approach to the transition points, and this finding is consistent with both the homogeneous-cortex prediction of increased correlation time (“critical slowing down”) near transition, and the recent, comprehensive anesthetic study by John et al.?[Conscious. Cogn. 10, 165 (2001)] reporting an increase in EEG coherence near the points of loss and recovery of consciousness. In addition, we find that if the long-range (corticocortical) excitatory-to-inhibitory connectivity in the 1D cortex is stronger than the long-range excitatory-to-excitatory connectivity, then the spatioadiabatic system can organize itself into large-amplitude spatial patterns (“dissipative structures”) consisting of giant stationary quasiperiodic voltage fluctuations distributed along the cortical rod.

Steyn-Ross, Moira L.; Steyn-Ross, D. A.; Sleigh, J. W.; Whiting, D. R.

2003-08-01

384

Measurement of the minority carrier diffusion length and edge surface-recombination velocity in InP  

NASA Technical Reports Server (NTRS)

A scanning electron microscope (SEM) was used to measure the electron (minority carrier) diffusion length (L(sub n)) and the edge surface-recombination velocity (V(sub s)) in zinc-doped Czochralski-grown InP wafers. Electron-beam-induced current (EBIC) profiles were obtained in specimens containing a Schottky barrier perpendicular to the scanned (edge) surface. An independent technique was used to measure V(sub s), and these values were used in a theoretical expression for normalized EBIC. A fit of the experimental data with this expression enabled us to determine L(sub n).

Bailey, Sheila G.; Hakimzadeh, Roshanak

1993-01-01

385

Second-harmonic microscopy of unstained living cardiac myocytes: measurements of sarcomere length with 20-nm accuracy  

NASA Astrophysics Data System (ADS)

We extend second-harmonic generation (SHG) microscopy to the measurement of sarcomere length in unstained living cardiac myocytes with 20-nm accuracy. We quantify individual sarcomere shortening in the presence of saxitoxin and find that it is in agreement with mechanical measurements of atrial tissue contracture. This functional application of SHG microscopy is generally applicable to quantify the physiological effects of drugs on contractile tissue. Our data also suggest that packed myosin heads in sarcomere thick filaments are responsible for the large second-harmonic endogenous signal in muscle tissue.

Boulesteix, Thierry; Beaurepaire, Emmanuel; Sauviat, Martin-Pierre; Schanne-Klein, Marie-Claire

2004-09-01

386

Length scales in alloy dissolution and measurement of absolute interfacial free energy.  

PubMed

De-alloying is the selective dissolution of one or more of the elemental components of an alloy. In binary alloys that exhibit complete solid solubility, de-alloying of the less noble component results in the formation of nanoporous metals, a materials class that has attracted attention for applications such as catalysis, sensing and actuation. In addition, the occurrence of de-alloying in metallic alloy systems under stress is known to result in stress-corrosion cracking, a key failure mechanism in fossil fuel and nuclear plants, ageing aircraft, and also an important concern in the design of nuclear-waste storage containers. Central to the design of corrosion-resistant alloys is the identification of a composition-dependent electrochemical critical potential, Vcrit, above which the current rises dramatically with potential, signalling the onset of bulk de-alloying. Below Vcrit, the surface is passivated by the accumulation of up to several monolayers of the more noble component. The current understanding of the processes that control Vcrit is incomplete. Here, we report on de-alloying results of Ag/Au superlattices that clarify the role of pre-existing length scales in alloy dissolution. Our data motivated us to re-analyse existing data on critical potentials of Ag-Au alloys and develop a simple unifying picture that accounts for the compositional dependence of solid-solution alloy critical potentials. PMID:17099702

Rugolo, J; Erlebacher, J; Sieradzki, K

2006-12-01

387

Water equivalent path length measurement in proton radiotherapy using time resolved diode dosimetry  

SciTech Connect

Purpose: To verify water equivalent path length (WEPL) before treatment in proton radiotherapy using time resolved in vivo diode dosimetry. Methods: Using a passively scattered range modulated proton beam, the output of a diode driving a fast current-to-voltage amplifier is recorded at a number of depths in a water tank. At each depth, a burst of overlapping single proton pulses is observed. The rms duration of the burst is computed and the resulting data set is fitted with a cubic polynomial. Results: When the diode is subsequently set to an arbitrary depth and the polynomial is used as a calibration curve, the ''unknown'' depth is determined within 0.3 mm rms. Conclusions: A diode or a diode array, placed (for instance) in the rectum in conjunction with a rectal balloon, can potentially determine the WEPL at that point, just prior to treatment, with submillimeter accuracy, allowing the beam energy to be adjusted. The associated unwanted dose is about 0.2% of a typical single fraction treatment dose.

Gottschalk, B.; Tang, S.; Bentefour, E. H.; Cascio, E. W.; Prieels, D.; Lu, H.-M. [Laboratory for Particle Physics and Cosmology, Harvard University, 18 Hammond Street, Cambridge, Massachusetts 02138 (United States); Francis H. Burr Proton Therapy Center, Boston, Massachusetts 02114 (United States); Ion Beam Applications S.A., Louvain-la-Neuve 1348 (Belgium); Francis H. Burr Proton Therapy Center, Boston, Massachusetts 02114 (United States); Ion Beam Applications S.A., Louvain-la-Neuve 1348 (Belgium); Francis H. Burr Proton Therapy Center, Boston, Massachusetts 02114 (United States)

2011-04-15

388

Influence of the chain length on the dynamic viscosity at high pressure of some 2-alkylamines: Measurements and comparative study of some models  

NASA Astrophysics Data System (ADS)

This work reports the dynamic viscosity data (a total of 93 points) of 2-alkylamines, which exhibit small association, consisting of 2-aminobutane, 2-aminopentane, 2-aminoheptane and 2-aminooctane at four temperatures between 293.15 K and 353.15 K (every 20 K), and pressures up to 100 MPa (every 20 MPa) which allows to study the influence of the chain length. A falling-body viscometer with an uncertainty of ±2% was used to perform these measurements. The variations of dynamic viscosity are discussed with respect to their behaviour due to chain length. Seven different models, most of them with a physical and theoretical background, are studied in order to investigate how they take the chain length effect into account through their required model parameters. The evaluated models are based on the empirical Vogel-Fulcher-Tamman (VFT) representation (combined with a Tait-like equation), the rough hard-sphere scheme, the concept of the free-volume, the friction theory, a correlation derived from molecular dynamics, a model based on Eyring's absolute rate theory combined with cubic EoS. A scaling viscosity representation has also been considered. These models need some adjustable parameters except the molecular dynamics correlation that is entirely predictive. Overall a satisfactory representation of the viscosity of these 2-alkylamines is found for the different models within the considered T, p range taking into account their simplicity. Moreover, it has been verified that the viscosity is a unique function of TV ? where the exponent ? is generally related to the steepness of the intermolecular repulsive potential ( T: temperature and V: specific volume).

Yoshimura, Masatoshi; Boned, Christian; Galliéro, Guillaume; Bazile, Jean-Patrick; Baylaucq, Antoine; Ushiki, Hideharu

2010-04-01

389

Hydrodynamic force measurements under precisely controlled conditions: Correlation of slip parameters with the mean free path  

NASA Astrophysics Data System (ADS)

A customized atomic force microscope has been utilized in dynamic mode to measure hydrodynamic forces between a sphere and a flat plate, both coated with gold. In order to study the influence of the mean free path on slippage without systematic errors due to varying surface properties, all data have been acquired at precisely the same spot on the plate. Local accommodation coefficients and slip lengths have been extracted from experimental data for He, Ne, Ar, Kr, as well as N2, CO2, and C2H6, at Knudsen numbers between 3 × 10-4 and 3. We found that slippage is effectively suppressed if the mean free path of the fluid is lower than the roughness amplitude on the surface, while we could not observe a clear correlation between the accommodation coefficient and the molecular mass.

Sedmik, René I. P.; Borghesani, Armando F.; Heeck, Kier; Iannuzzi, Davide

2013-04-01

390

The spin Hall angle and spin diffusion length of Pd measured by spin pumping and microwave photoresistance  

NASA Astrophysics Data System (ADS)

We present the experimental study of the spin Hall angle (SHA) and spin diffusion length of Pd with the spin pumping and microwave photoresistance effects. The Py/Pd bilayer stripes are excited with an out-of-plane microwave magnetic field. The pure spin current is thus pumped and transforms into charge current via the inverse spin Hall effect (ISHE) in Pd layer, yielding an ISHE voltage. The ISHE voltage can be distinguished from the unwanted signal caused by the anisotropic magnetoresistance according to their different symmetries. Together with Pd thickness dependent measurements of in and out-of-plane precessing angles and effective spin mixing conductance, the SHA and spin-diffusion length of Pd are quantified as 0.0056 ± 0.0007 and 7.3 ± 0.7 nm, respectively.

Tao, X. D.; Feng, Z.; Miao, B. F.; Sun, L.; You, B.; Wu, D.; Du, J.; Zhang, W.; Ding, H. F.

2014-05-01

391

A New Measurement Method of the Delay Line Length in the X-band Delay Line Distribution System(DLDS)  

NASA Astrophysics Data System (ADS)

In order to control the driving RF phase at the input of the accelerating structure of X-band linear collider main linacs, it is necessary to measure the length of the long TE01 mode delay lines of 40-80m. A new measurement scheme by using the low frequency resonant mode of the TE01mode delay line was proposed. The delay lines have the tapered guide on its both ends, thus the low frequency resonant mode around 2GHz can be the measure of the delay line dimensions. The operational principle and the elementary characteristics of this measurement method such as, sensitivity, S/N ratio and other basic design parameters are presented.

Tamura, F.; Mizuno, H.

1997-05-01

392

Measurement of viscoelastic properties at small length scales for heterogeneous and nonlinear materials  

NASA Astrophysics Data System (ADS)

In this dissertation, advances in linear and non-linear viscoelastic analysis and experimentation have been employed to investigate the properties of materials using nanoindentation. In the first study, a general linear-viscoelastic model was developed to measure the properties of polydimethylsiloxane (PDMS) using a flat punch indenter. Subsequently, linear viscoelastic nanoindentation was used to measure the young's relaxation modulus of a locally-heterogeneous thermally-aged bismaleimide resin using a Berkovich indenter. Nanoindentation measurements were conducted on both surface and cross section of aged bismaleimide resin specimens with different aging time at 200°C and 300°C respectively to extract the oxidation effect of sample under high temperatures. Finally, nanoindentation measurements were made on human tympanic membrane specimens with using a spherical nanoindenter tip in direct contact with the collagen fiber layer. Linear viscoelastic analysis was conducted to extract the Young's relaxation modulus distributions. The study also focused on the development of non-linear viscoelastic analysis of indentation experiments. Despite the fact that the nanoindentation technique is well established for the characterization of elasto-plastic materials, nanoindentation on viscoelastic materials is not fully understood especially in nonlinear viscoelastic region. In the dissertation, a nonlinear viscoelastic model was developed and implemented in Abaqus/Implicit Code to analyze the nonlinear visceoelastic behavior of polyvinyl acetate (PVA) under nanoindentation.

Wang, Fang

393

Evaluation of Length-of-Stain Gas Indicator Tubes for Measuring Carbon Monoxide in Air.  

ERIC Educational Resources Information Center

Techniques for detection and measurement of carbon monoxide (CO) in air are of interest and utility in many aspects of automotive safety. CO concentrations may range from less than 100 parts per million (ppm), or 0.01 percent, to about 10 percent by volume. Gas indicator tubes have been used for many years primarily as detectors of hazardous gases…

Klaubert, Earl C.; And Others

394

Measurement of cell surface protein dynamics by two-photon image correlation spectroscopy and image cross-correlation spectroscopy  

Microsoft Academic Search

Advances in laser-scanning microscopy and the advent of confocal microscopy permitted the development of image correlation spectroscopy (ICS). ICS is an imaging analog of fluorescence correlation spectroscopy (FCS) optimized for measuring the aggregation state of fluorescently labeled macromolecules on the surface of biological cells. The ICS method entails spatial autocorrelation analysis of fluorescence fluctuations within an image sampled from an

Paul W. Wiseman; Jeffrey A. Squier

2002-01-01

395

In situ multiproperty measurements of individual nanomaterials in SEM and correlation with their atomic structures.  

PubMed

The relationship between property and structure is one of the most important fundamental questions in the field of nanomaterials and nanodevices. Understanding the multiproperties of a given nano-object also aids in the development of novel nanomaterials and nanodevices. In this paper, we develop for the first time a comprehensive platform for in situ multiproperty measurements of individual nanomaterials using a scanning electron microscope (SEM). Mechanical, electrical, electromechanical, optical, and photoelectronic properties of individual nanomaterials, with lengths that range from less than 200 nm to 20 ?m, can be measured in situ with an SEM on the platform under precisely controlled single-axial strain and environment. An individual single-walled carbon nanotube (SWCNT) was measured on the platform. Three-terminal electronic measurements in a field effect transistor structure showed that the SWCNT was semiconducting and agreed with the structure characterization by transmission electron microscopy after the in situ measurements. Importantly, we observed a bandgap increase of this SWCNT with increasing axial strain, and for the first time, the experimental results quantitatively agree with theoretical predictions calculated using the chirality of the SWCNT. The vibration performance of the SWCNT, a double-walled CNT, and a triple-walled CNT were also studied as a function of axial strain, and were proved to be in good agreement with classical beam theory, although the CNTs only have one, two, or three atomic layers, respectively. Our platform has wide applications in correlating multiproperties of the same individual nanostructures with their atomic structures. PMID:24959846

Ning, Z Y; Fu, M Q; Shi, T W; Guo, Y; Wei, X L; Gao, S; Chen, Q

2014-07-11

396

Optical absorption coefficient and minority carrier diffusion length measurements in low-cost silicon solar cell material  

SciTech Connect

The optical absorption coefficient of silicon solar cell material grown by three low-cost growth methods was measured in the wavelength interval 0.8< or =lambda< or =1.0 ..mu..m, the wavelength region of interest in surface photovoltage measurements of the minority carrier diffusion length. The square root of the absorption coefficient was found to vary linearly with photon energy over the wavelengths studied, and the measured data agree with a linear empirical fit to within 0.5% RMS. The absorption coefficients obtained are slightly lower than those reported by Runyan, with the greatest disagreement at long wavelengths. Minority carrier diffusion lengths computed using the present absorption coefficients are approximately 16% greater than those calculated using Runyan's data. Excellent sample-to-sample agreement within and between lots indicates that for two of the growth methods studied, material quality as judged by optical properties has not been sacrificed by the use of low-cost growth methods. Samples grown by the third growth method studied showed measurably poorer optical quality.

Swimm, R.T.; Dumas, K.A.

1982-11-01

397

Precision intensities and angular correlation measurements in ^152Sm  

NASA Astrophysics Data System (ADS)

The samarium isotopic chain shows great structural change dripline-to-dripline; evolving from deformed at the proton dripline, through spherical near stability before undergoing another transformation near N=90 when large prolate deformation re-emerges. Lying at the midpoint of this latter transition is ^152Sm. Numerous models have been developed to explain ^152Sm in terms of either being at the critical point of a phase transition, or in terms of coexisting shapes. To test the validity of these different models, a beta-decay experiment was performed at the ATLAS facility at Argonne. The decay of ^152Eu to ^152Sm was studied through gamma-ray spectroscopy using Gammasphere. An extremely large data set was collected, consisting of > 7x10^9 gamma-gamma or higher fold events. This made possible a high precision measurement of energies and intensities and very definite angular correlation determinations. The new results resolve some previous experimental ambiguities and help to differentiate between theoretical models. Work supported by the DOE Office of Nuclear Physics under contract DE-AC02-06CH11357.

McCutchan, E. A.; Lister, C. J.; Zhu, S.; Carpenter, M. P.; Janssens, R. V. F.; Khoo, T. L.; Lauritsen, T.; Seweryniak, D.

2010-11-01

398

Feasibility study for transuranic nuclide measurement on long-length contaminated equipment using neutron detection  

Microsoft Academic Search

The feasibility of measuring the transuranic (TRU) nuclide content of equipment removed from Hanford`s high-level radioactive-waste tanks has been established for components heavier than about 30 kg\\/m (20 lbs\\/ft). This conclusion has been reached based on experience with the TRU assay of waste burial boxes, planned improvements to the assay equipment design and assay methodology, and experimental investigation of neutron

D. C. Stromswold; A. J. Peurrung; R. J. Arthur

1995-01-01

399

Effect of detergent alkyl chain length on crystallization of a detergent-solubilized membrane protein:. correlation of protein-detergent particle size and particle-particle interaction with crystallization of the photosynthetic reaction center from Rhodobacter sphaeroides  

NASA Astrophysics Data System (ADS)

The effect of detergent alkyl chain length on the crystallization of detergent-solubilized membrane proteins was characterized using the reaction center (RC) from Rhodobacter sphaeroides as a model. Crystallization was performed in the presence of both n-alkyl-?-D-glucopyranosides, C nG, where the alkyl chain length, n, was varied from 8 to 10, and dodecyl-dimethylamine-N-oxide (C 12DAO). A pronounced effect of detergent chain length was found on the ability to crystallize the reaction center. Small-angle neutron scattering measurements (SANS) demonstrated that the variation in the ability to crystallize the reaction center is correlated with changes in the apparent radius of gyration, Rg, of the reaction center-detergent particle, reflecting changes in the size of the reaction center and strength of the inter-particle interactions. Specifically, reaction center crystallization in the absence of additional amphiphiles was found to occur only with octylglucoside, C 8G. Crystallization in the presence of longer chain detergents, C 9G, C 10G, C 12DAO, required the use of an additional small amphiphile, heptanetriol (HT). SANS measurements showed that the apparent Rg of the reaction center-detergent particle increased with increasing detergent chain length, and that the addition of HT reduces this parameter. The addition of HT was found to impede crystallization in the presence of C 8G. This inhibition could be reversed by increasing C 8G concentration with respect to HT, resulting in the formation of alternate crystal forms. Taken together, these results suggest that detergents and small molecule amphiphiles used in membrane protein crystallization must be chosen to optimize both the size and solubility of the protein-detergent particle. Data for the reaction center suggest that crystallization occurs within a restricted range of size of the protein-detergent complex.

Marone, Palma Ann; Thiyagarajan, P.; Wagner, Arlene M.; Tiede, David M.

1999-12-01

400

An evolutionarily conserved family of virion tail needles related to bacteriophage P22 gp26: correlation between structural stability and length of the ?-helical trimeric coiled-coil  

PubMed Central

Bacteriophages of the Podoviridae family use short non-contractile tails to inject their genetic material into Gram-negative bacteria. In phage P22, the tail contains a thin needle, encoded by the phage gene 26, which is essential both for stabilization and ejection of the packaged viral genome. Bio-informatic analysis of the N-terminal domain of gp26 (residues 1–60) led us to identify a family of genes encoding putative homologues of the tail needle gp26. To validate this idea experimentally and to explore their diversity, we cloned the gp26-like gene from phages HK620, Sf6, HS1, and characterized these gene products in solution. All gp26-like factors contain an elongated ?-helical coiled-coil core consisting of repeating, adjacent trimerization heptads and form trimeric fibers with length ranging between about 240Å to 300Å. Gp26-tail needles display high structural stability in solution, with Tm (temperature of melting) between 85–95°C. To determine how the structural stability of these phage fibers correlates with the length of the ?-helical core, we investigated the effect of insertions and deletions in the helical core. In P22 tail needle, we identified an 85-residue long helical domain, termed MiCRU (Minimal Coiled-coil Repeat Unit), that can be inserted in frame inside gp26 helical core, preserving the straight morphology of the fiber. Likewise, we were able to remove three quarters of the helical core of HS1 tail needle minimally decreasing the stability of the fiber. We conclude that in the gp26 family of tail needles, structural stability increases non-linearly with the length of the ?-helical core. Thus, the overall stability of these bacteriophage fibers is not solely dependent on the number of trimerization repeats in the ?-helical core.

Bhardwaj, Anshul; Walker-Kopp, Nancy; Casjens, Sherwood R.; Cingolani, Gino

2009-01-01

401

Inter-ELM power decay length for JET and ASDEX upgrade: measurement and comparison with heuristic drift-based model.  

PubMed

Experimental measurements of the SOL power decay length (?(q)) estimated from analysis of fully attached divertor heat load profiles from two tokamaks, JET and ASDEX Upgrade, are presented. Data was measured by means of infrared thermography. An empirical scaling reveals parametric dependency ?(q) in mm = 0.73B(T)(-0.78)q(cyl)(1.2)P(SOL)(0.1)R(geo)(0), where B(T)(T) describes the toroidal magnetic field, q(cyl) the cylindrical safety factor, P(SOL)(MW) the power crossing the separatrix and R(geo)(m) the major radius of the device. A comparison of these measurements to a heuristic particle drift-based model shows satisfactory agreement in both absolute magnitude and scaling. Extrapolation to ITER gives ?(q) ? 1 mm. PMID:22181888

Eich, T; Sieglin, B; Scarabosio, A; Fundamenski, W; Goldston, R J; Herrmann, A

2011-11-18

402

Measurement of the spatial backscattering impulse-response at short length-scales with polarized enhanced backscattering (EBS)  

PubMed Central

In this Letter, we describe an easy to implement technique to measure the spatial backscattering impulse-response at length-scales shorter than a transport mean free path with resolution of better than 10 ?m using the enhanced backscattering (EBS) phenomenon. This technique enables spectroscopic measurements throughout the visible range and sensitivity to all polarization channels. Through a combination of Monte Carlo simulations and experimental measurements of latex microspheres, we explore the various sensitivities of our technique to both intrinsic sample properties and extrinsic instrumental properties. We conclude by demonstrating the extraordinary sensitivity of our technique to the shape of the scattering phase function, including higher order shape parameters than the anisotropy factor (or first moment).

Radosevich, Andrew J.; Mutyal, Nikhil N.; Turzhitsky, Vladimir; Rogers, Jeremy D.; Yi, Ji; Taflove, Allen; Backman, Vadim

2012-01-01

403

Contact Angle Measurements by AFM on Droplets of Intermediate-Length Alkanes Adsorbed on SiO2 Surfaces  

NASA Astrophysics Data System (ADS)

We have recently discovered that films of intermediate-length alkanes (n-CnH2n+2; 24 < n < 40) do not completely wet a SiO2 surface on a nanometer length scale [2]. In a narrow temperature range near the bulk melting point Tb, we observe a single layer of molecules oriented with their long axis perpendicular to the surface. On heating just above Tb, these molecules undergo a delayering transition to three-dimensional droplets that remain present up to their evaporation point. Here we report measurements by noncontact Atomic Force Microscopy of the contact angle of these droplets for a film of hexatriacontane (n-C36H74 or C36). Our preliminary measurements indicate that there is a weak maximum in the contact angle at ˜Tb + 3 C. Further measurements are planned to investigate whether the weak maximum in the contact angle is consistent with the droplets supporting a surface freezing effect as at the bulk fluid/air interface. ^2M. Bai, K. Knorr, M. J. Simpson, S. Trogisch, H. Taub, S. N. Ehrlich, H. Mo, U. G. Volkmann, F. Y. Hansen, cond-mat/0611497.

Bai, M.; Taub, H.; Knorr, K.; Volkmann, U. G.; Hansen, F. Y.

2007-03-01

404

Multiple Measures of Adiposity Are Associated with Mean Leukocyte Telomere Length in the Northern Finland Birth Cohort 1966  

PubMed Central

Studies of leukocyte telomere length (LTL) and adiposity have produced conflicting results, and the relationship between body mass index (BMI) and telomere length throughout life remains unclear. We therefore tested association of adult LTL measured in 5,598 participants with: i) childhood growth measures (BMI and age at adiposity rebound (AR)); ii) change in BMI from childhood to adulthood and iii) adult BMI, waist-to-hip ratio (WHR), body adiposity index (BAI). Childhood BMI at AR was positively associated with LTL at 31 years in women (P?=?0.041). Adult BMI and WHR in both men (P?=?0.025 and P?=?0.049, respectively) and women (P?=?0.029 and P?=?0.008, respectively), and BAI in women (P?=?0.021) were inversely associated with LTL at 31 years. An increase in standardised BMI between early childhood and adulthood was associated with shorter adult LTL in women (P?=?0.008). We show that LTL is inversely associated with multiple measures of adiposity in both men and women. Additionally, BMI increase in women from childhood to adulthood is associated with shorter telomeres at age 31, potentially indicating accelerated biological ageing.

Rodriguez, Alina; Kaakinen, Marika; Couto Alves, Alexessander; Sebert, Sylvain; Millwood, Iona Y.; Laitinen, Jaana; O'Reilly, Paul F.; Jarvelin, Marjo-Riitta; Blakemore, Alexandra I. F.

2014-01-01

405

Measurement of diffusion lengths in quaternary semiconducting thin layers by spectrum imaging  

NASA Astrophysics Data System (ADS)

A method is described to detect and measure diffusion in complex layer systems. The technique of spectrum imaging is a combination of electron energy-loss spectroscopy and imaging in a transmission electron microscope with imaging energy filter. It allows to extract chemical profiles with a spatial resolution of about 1 nm at a compositional sensitivity better than 1 at% for most elements. This has been applied to multilayers of quaternary semiconductors, where simple electron microscopy based imaging techniques cannot distinguish between the diffusion of different atomic species. The diffusivities of sulphur in ZnMgSSe/ZnSe quantum well laser structures and of magnesium and manganese across interfaces in CdMnTe/CdTe/CdMgTe quantum wells have been determined.

Walther, T.

2001-12-01

406

Review and analysis of VHF/UHF field strength measurements: Measurements at VHF over path lengths greater than 100 km  

NASA Astrophysics Data System (ADS)

In 1983 CCIRIWP 5/5 put forward a number of proposals for improvements to the field strength prediction methods of CCIR Recommendation 370 and associated Report 239, as used for international planning negotiations in the VHF and UHF Broadcast Bands. Described are the results of studies carried out by the BBC, in conjunction with other propagation investigations, to assess the validity of those proposals of IWP 5/5 which relate to propagation over path lengths in excess of about 100 km in the VHF Bands. It is concluded that these proposals can be supported with only one exception, relating to an addition of 7 dB to beyond-horizon oversea curves. Subsequently, the VHF proposals (excepting the one relating to the 7 dB correction) have been endorsed by CCIR Study Group 5 and adopted by the Plenar Meeting in 1986 for inclusion as modifications to Recommendation 370. Even so, limitations in the exsiting methods are identified and further work is proposed.

Sandell, R. S.; Bell, C. P.; Taplin, D. W.

1986-12-01

407

Correlation  

NSDL National Science Digital Library

This chapter will discuss the concept of correlation , which is used in later chapters that will explain the concepts of validity and reliability. Here, the authors introduce the Pearson correlation coefficient, a statistic that is used with ratio

Christmann, Edwin P.; Badgett, John L.

2008-11-01

408

Effectively classically correlated state of a measured system and a bosonic measurement apparatus  

SciTech Connect

We consider a multilevel system coupled to a bosonic measurement apparatus. We derive exact expressions for the time-dependent expectation values of a large class of physically relevant observables that depend on degrees of freedom of both systems. We find that, for this class, though the two systems become entangled as a result of their interaction, they appear classically correlated for long enough times. The unique corresponding time-dependent separable state is determined explicitly. To better understand the physical parameters that control the time scale of this effective disentanglement process, we study a one-dimensional measurement apparatus.

Camalet, S. [Laboratoire de Physique Theorique de la Matiere Condensee, UMR 7600, Universite Pierre et Marie Curie, 4, place Jussieu, F-75005 Paris (France)

2011-04-15

409

Clinical Correlates to Laboratory Measures for use in Non-Contact Anterior Cruciate Ligament Injury Risk Prediction Algorithm  

PubMed Central

Background Prospective measures of high knee abduction moment during landing identify female athletes at high risk for non-contact anterior cruciate ligament injury. Biomechanical laboratory measurements predict high knee abduction moment landing mechanics with high sensitivity (85%) and specificity (93%). The purpose of this study was to identify correlates to laboratory-based predictors of high knee abduction moment for use in a clinic-based anterior cruciate ligament injury risk prediction algorithm. The hypothesis was that clinically obtainable correlates derived from the highly predictive laboratory-based models would demonstrate high accuracy to determine high knee abduction moment status. Methods Female basketball and soccer players (N=744) were tested for anthropometrics, strength and landing biomechanics. Pearson correlation was used to identify clinically feasible correlates and logistic regression to obtain optimal models for high knee abduction moment prediction. Findings Clinical correlates to laboratory-based measures were identified and predicted high knee abduction moment status with 73% sensitivity and 70% specificity. The clinic-based prediction algorithm, including (Odds Ratio: 95% confidence interval) knee valgus motion (1.43:1.30–1.59 cm), knee flexion range of motion (.98:0.96–1.01 deg), body mass (1.04:1.02–1.06 kg), tibia length (1.38:1.25–1.52 cm) and quadriceps to hamstring ratio (1.70:1.06–2.70) predicted high knee abduction moment status with C statistic 0.81. Interpretation The combined correlates of increased knee valgus motion, knee flexion range of motion, body mass, tibia length and quadriceps to hamstrings ratio predict high knee abduction moment status in female athletes with high sensitivity and specificity.

Myer, Gregory D.; Ford, Kevin R.; Khoury, Jane; Succop, Paul; Hewett, Timothy E.

2010-01-01

410

Theory and Measurement of Partially Correlated Persistent Scatterers  

NASA Astrophysics Data System (ADS)

Interferometric synthetic aperture radar (InSAR) time-series methods can effectively estimate temporal surface changes induced by geophysical phenomena. However, such methods are susceptible to decorrelation due to spatial and temporal baselines (radar pass separation), changes in orbital geometries, atmosphere, and noise. These effects limit the number of interferograms that can be used for differential analysis and obscure the deformation signal. InSAR decorrelation effects may be ameliorated by exploiting pixels that exhibit phase stability across the stack of interferograms. These so-called persistent scatterer (PS) pixels are dominated by a single point-like scatterer that remains phase-stable over the spatial and temporal baseline. By identifying a network of PS pixels for use in phase unwrapping, reliable deformation measurements may be obtained even in areas of low correlation, where traditional InSAR techniques fail to produce useful observations. PS identification is challenging in natural terrain, due to low reflectivity and few corner reflectors. Shanker and Zebker [1] proposed a PS pixel selection technique based on maximum-likelihood estimation of the associated signal-to-clutter ratio (SCR). In this study, we further develop the underlying theory for their technique, starting from statistical backscatter characteristics of PS pixels. We derive closed-form expressions for the spatial, rotational, and temporal decorrelation of PS pixels as a function of baseline and signal-to-clutter ratio. We show that previous decorrelation and critical baseline expressions [2] are limiting cases of our result. We then describe a series of radar scattering simulations and show that the simulated decorrelation matches well with our analytic results. Finally, we use our decorrelation expressions with maximum-likelihood SCR estimation to analyze an area of the Hayward Fault Zone in the San Francisco Bay Area. A series of 38 images of the area were obtained from C-band ERS radar satellite passes between May 1995 and December 2000. We show that the interferogram stack exhibits PS decorrelation trends in agreement with our analytic results. References 1. P. Shanker and H. Zebker, "Persistent scatterer selection using maximum likelihood estimation," Geophysical Research Letters, Vol. 34, L22301, 2007. 2. H. Zebker and J. Villasenor, "Decorrelation in Interferometric Radar Echos," IEEE Transactions on Geoscience and Remote Sensing, Vol. 30, No. 5, Sept. 1992.

Lien, J.; Zebker, H. A.

2011-12-01

411

Expectations for dihadron correlation measurements extrapolated to 5.5A TeV  

SciTech Connect

The suppression of high transverse momentum (P{sub T}) inclusive hadron spectra in heavy-ion collisions as compared to the scaled expectation of high P{sub T} hadron production in p-p collisions is the most direct manifestation of the interaction of hard partons with the soft bulk medium produced in heavy-ion collisions which is absent in p-p collisions. Yet the measured nuclear suppression factor R{sub AA} is a very averaged quantity and hence only a limited amount of information about the medium evolution and the nature of the interaction with the medium can be deduced from R{sub AA}. Measurements of hard back-to-back hadron correlations in 200A GeV Au-Au collisions at RHIC have opened a new window to study the energy loss of partons in a medium in a more differential way and for a different distribution of in-medium path lengths than in the case of R{sub AA}. In this work, we present an extrapolation of our results for back-to-back yields at RHIC energies to 5.5 TeV Pb-Pb collisions at the CERN LHC. We also discuss differences and similarities between the measurement at RHIC.

Renk, Thorsten; Eskola, Kari J. [Department of Physics, P. O. Box 35, University of Jyvaeskylae, FI-40014 Jyvaeskylae (Finland) and Helsinki Institute of Physics, P. O. Box 64, University of Helsinki, FI-00014 Helsinki (Finland)

2008-04-15

412

A New Non-Invasive Ultrasonic Method for Measurements of Longitudinal Length Alteration of the Arterial Wall-First in vivo trial  

NASA Astrophysics Data System (ADS)

We have recently shown that there is a previous unknown longitudinal movement present in the arterial wall. We aim now to investigate whether the longitudinal movement causes length alteration of the arterial wall. The objective of this paper was to describe a new non-invasive ultrasonic technique that measures the length alteration of arteries in human in-vivo. Results indicate that a significant length alteration is present in the common carotid artery.

Cinthio, M.; Ahlgren, Å. R.; Persson, H. W.; Lindström, K.

413

Magnetoelastic coupling and charge correlation lengths in a twin domain of Ba(Fe1-xCox)2As2 (x=0.047): A high-resolution x-ray diffraction study  

NASA Astrophysics Data System (ADS)

The interplay between structure, magnetism, and superconductivity in single crystal Ba(Fe1-xCox)2As2 (x=0.047) has been studied using high-resolution x-ray diffraction by monitoring charge Bragg reflections in each twin domain separately. The emergence of the superconducting state is correlated with the suppression of the orthorhombic distortion around TC, exhibiting competition between orthorhombicity and superconductivity. Above TS, the in-plane charge correlation length increases with the decrease of temperature, possibly induced by nematic fluctuations in the paramagnetic tetragonal phase. Upon cooling, anomalies in the in-plane charge correlation lengths along a (?a) and b axes (?b) are observed at TS and also at TN indicative of strong magnetoelastic coupling. The in-plane charge correlation lengths are found to exhibit anisotropic behavior along and perpendicular to the in-plane component of stripe-type AFM wave vector (101)O below around TN. The temperature dependence of the out-of-plane charge correlation length shows a single anomaly at TN, r