Gyromagnetically Induced Transparency of Meta-Surfaces
Mousavi, S Hossein; Allen, Jeffery; Allen, Monica; Shvets, Gennady
2013-01-01
We demonstrate that the violation of the time-reversal (TR) symmetry in the presence of a gyromagnetic substrate can produce an analog of electromagnetically induced transparency in metallic meta-molecules. The simplest implementation of such gyromagnetically induced transparency (GIT) in a meta-surface comprised of an array of resonant antenna pairs placed on a gyromagnetic substrate and illuminated by a normally incident electromagnetic wave is analyzed. TR symmetry breaking introduced by the magnetic field makes meta-molecules bi-anisotropic and causes spectrally-sharp Fano interference between the otherwise uncoupled electric and magnetic dipolar resonances of the meta-molecules. The applied magnetic field results in a sharp transmission peak through the otherwise reflective meta-surface. We show that, for oblique wave incidence, one-way GIT can be achieved by the combination of spatial dispersion and TR symmetry breaking. These theoretically predicted phenomena pave the way to non-reciprocal switches and...
Nonreciprocal Electromagnetic Devices in Gyromagnetic Photonic Crystals
Li, Zhi-Yuan; Liu, Rong-Juan; Gan, Lin; Fu, Jin-Xin; Lian, Jin
2014-01-01
Gyromagnetic photonic crystal (GPC) offers a promising way to realize robust transport of electromagnetic waves against backscattering from various disorders, perturbations and obstacles due to existence of unique topological electromagnetic states. The dc magnetic field exerting upon the GPC brings about the time-reversal symmetry breaking, splits the band degeneracy and opens band gaps where the topological chiral edge states (CESs) arise. The band gap can originate either from long-range Bragg-scattering effect or from short-range localized magnetic surface plasmon resonance (MSP). These topological edge states can be explored to construct backscattering-immune one-way waveguide and other nonreciprocal electromagnetic devices. In this paper we review our recent theoretical and experimental studies of the unique electromagnetic properties of nonreciprocal devices built in GPCs. We will discuss various basic issues like experimental instrumental setup, sample preparations, numerical simulation methods, tunable properties against magnetic field, band degeneracy breaking and band gap opening and creation of topological CESs. We will investigate the unidirectional transport properties of one-way waveguide under the influence of waveguide geometries, interface morphologies, intruding obstacles, impedance mismatch, lattice disorders, and material dissipation loss. We will discuss the unique coupling properties between one-wave waveguide and resonant cavities and their application as novel one-way bandstop filter and one-way channel-drop filter. We will also compare the CESs created in the Bragg-scattering band gap and the MSP band gap under the influence of lattice disorders. These results can be helpful for designing and exploring novel nonreciprocal electromagnetic devices for optical integration and information processing.
Robust edge states in amorphous gyromagnetic photonic lattices
Mansha, Shampy; Chong, Y. D.
2017-09-01
We numerically study amorphous analogs of a two-dimensional photonic Chern insulator. The amorphous lattices consist of gyromagnetic rods that break time-reversal symmetry, with the lattice sites generated by a close-packing algorithm. The level of short-range order is adjustable, and there is no long-range order. The topologically nontrivial gaps of the photonic Chern insulator are found to persist into the amorphous regime, so long as there is sufficient short-range order. Strongly nonreciprocal robust transmission occurs via edge states, which are shown to propagate ballistically despite the absence of long-range order, and to be exponentially localized along the lattice edge. Interestingly, there is an enhancement of nonreciprocal transmission even at very low levels of short-range order, where there are no discernible spectral gaps.
Precision Measurement of the Electron/Muon Gyromagnetic Factors
Awobode, A M
2010-01-01
Clear, persuasive arguments are brought forward to motivate the need for highly precise measurements of the electron/muon orbital g, i.e. gL. First, we briefly review results obtained using an extended Dirac equation, which conclusively showed that, as a consequence of quantum relativistic corrections arising from the time-dependence of the rest-energy, the electron gyromagnetic factors are corrected. It is next demonstrated, using the data of Kusch & Foley on the measurement of deltaS minus 2 deltaL together with the modern precise measurements of the electron deltaS where deltaS identically equal to gS minus 2, that deltaL may be a small, non-zero quantity, where we have assumed Russel-Saunders LS coupling and proposed, along with Kusch and Foley, that gS = 2 plus deltaS and gS = 1 plus deltaL. Therefore, there is probable evidence from experimental data that gS is not exactly equal to 1; the expectation that quantum effects will significantly modify the classical value of the orbital g is therefore rea...
Rotating Spacetimes with Asymptotic Non-Flat Structure and the Gyromagnetic Ratio
Aliev, Alikram N
2007-01-01
In general relativity, the gyromagnetic ratio for all stationary, axisymmetric and asymptotically flat spacetimes is known to be g=2. In this paper, we continue our previous works of examination this result for rotating charged spacetimes with asymptotic non-flat structure. We first consider two instructive examples of these spacetimes: The spacetime of a Kerr-Newman black hole with a straight cosmic string on its axis of symmetry and the Kerr-Newman Taub-NUT spacetime. We show that for both spacetimes the gyromagnetic ratio g=2 independent of their asymptotic structure. We also extend this result to a general class of metrics which admit separation of variables for the Hamilton-Jacobi and wave equations. We proceed with the study of the gyromagnetic ratio in higher dimensions by considering the general solution for rotating charged black holes in minimal five-dimensional gauged supergravity. We obtain the analytic expressions for two distinct gyromagnetic ratios of these black holes that are associated with ...
Andreev, V. V.; Novitskii, A. A.; Umnov, A. M.; Chuprov, D. V.
2016-06-01
The spatial configuration of a relativistic plasma bunch generated under the gyromagnetic autoresonance and confined in a magnetic mirror trap has been studied experimentally and numerically. The characteristics of bremsstrahlung generated by the plasma bunch from the gas and chamber walls were investigated using X-ray spectroscopy and radiometry, which made it possible to determine the localization of the bunch and analyze the dynamics of its confinement.
Gyromagnetic factor of rotating disks of electrically charged dust in general relativity
Liu Pynn, Yu-Chun; Macedo, Rodrigo Panosso; Breithaupt, Martin; Palenta, Stefan; Meinel, Reinhard
2016-11-01
We calculated the dimensionless gyromagnetic ratio ("g -factor") of self-gravitating, uniformly rotating disks of dust with a constant specific charge ɛ . These disk solutions to the Einstein-Maxwell equations depend on ɛ and a "relativity parameter" γ (0 <γ ≤1 ) up to a scaling parameter. Accordingly, the g -factor is a function g =g (γ ,ɛ ). The Newtonian limit is characterized by γ ≪1 , whereas γ →1 leads to a black-hole limit. The g -factor, for all ɛ , approaches the values g =1 as γ →0 and g =2 as γ →1 .
The proton gyromagnetic ratio by low field method measured at KRISS
Park, P G; Kim, C S; Shifrin, V Y; Khorev, V N
1999-01-01
The proton gyromagnetic ratio (gamma sup ' sub p) in water has been obtained by the low-field method using the atomic magnetic resonance in sup 4 He, a multi-current solenoid and an induction technique for the dimensional measurement for the solenoid. The final result is gamma sup ' sub p (low) = 2.675 154 18 x 10 sup 8 s sup - sup 1 T sup - sup 1 (0.18 x 10 sup - sup 6 , by K sub j sub - sub 9 sub 0 = 483 597.9 GHz/V, R sub k sub - sub 9 sub 0 = 25 812.807 OMEGA).
Gyromagnetic factor of rotating disks of electrically charged dust in general relativity
Pynn, Yu-Chun; Breithaupt, Martin; Palenta, Stefan; Meinel, Reinhard
2016-01-01
We calculated the dimensionless gyromagnetic ratio ("$g$-factor") of self-gravitating, uniformly rotating disks of dust with a constant specific charge $\\epsilon$. These disk solutions to the Einstein-Maxwell equations depend on $\\epsilon$ and a "relativity parameter" $\\gamma$ ($0<\\gamma\\le 1$) up to a scaling parameter. Accordingly, the $g$-factor is a function $g=g(\\gamma,\\epsilon)$. The Newtonian limit is characterized by $\\gamma \\ll 1$, whereas $\\gamma\\to 1$ leads to a black-hole limit. The $g$-factor, for all $\\epsilon$, approaches the values $g=1$ as $\\gamma\\to 0$ and $g=2$ as $\\gamma\\to 1$.
Bias-field controlled phasing and power combination of gyromagnetic nonlinear transmission lines.
Reale, D V; Bragg, J-W B; Gonsalves, N R; Johnson, J M; Neuber, A A; Dickens, J C; Mankowski, J J
2014-05-01
Gyromagnetic Nonlinear Transmission Lines (NLTLs) generate microwaves through the damped gyromagnetic precession of the magnetic moments in ferrimagnetic material, and are thus utilized as compact, solid-state, frequency agile, high power microwave (HPM) sources. The output frequency of a NLTL can be adjusted by control of the externally applied bias field and incident voltage pulse without physical alteration to the structure of the device. This property provides a frequency tuning capability not seen in many conventional e-beam based HPM sources. The NLTLs developed and tested are mesoband sources capable of generating MW power levels in the L, S, and C bands of the microwave spectrum. For an individual NLTL the output power at a given frequency is determined by several factors including the intrinsic properties of the ferrimagnetic material and the transmission line structure. Hence, if higher power levels are to be achieved, it is necessary to combine the outputs of multiple NLTLs. This can be accomplished in free space using antennas or in a transmission line via a power combiner. Using a bias-field controlled delay, a transient, high voltage, coaxial, three port, power combiner was designed and tested. Experimental results are compared with the results of a transient COMSOL simulation to evaluate combiner performance.
Reale, D V; Parson, J M; Neuber, A A; Dickens, J C; Mankowski, J J
2016-03-01
A stripline gyromagnetic nonlinear transmission line (NLTL) was constructed out of yttrium iron garnet ferrite and tested at charge voltages of 35 kV-55 kV with bias fields ranging from 10 kA/m to 20 kA/m. Typically, high power gyromagnetic NLTLs are constructed in a coaxial geometry. While this approach has many advantages, including a uniform transverse electromagnetic (TEM) mode, simple interconnection between components, and the ability to use oil or pressurized gas as an insulator, the coaxial implementation suffers from complexity of construction, especially when using a solid insulator. By moving to a simpler transmission line geometry, NLTLs can be constructed more easily and arrayed on a single substrate. This work represents a first step in exploring the suitability of various transmission line structures, such as microstrips and coplanar waveguides. The resulting high power microwave (HPM) source operates in ultra high frequency (UHF) band with an average bandwidth of 40.1% and peak rf power from 2 MW to 12.7 MW.
Johnson, J. M.; Reale, D. V.; Krile, J. T.; Garcia, R. S.; Cravey, W. H.; Neuber, A. A.; Dickens, J. C.; Mankowski, J. J.
2016-05-01
In this paper, a solid-state four element array gyromagnetic nonlinear transmission line high power microwave system is presented as well as a detailed description of its subsystems and general output capabilities. This frequency agile S-band source is easily adjusted from 2-4 GHz by way of a DC driven biasing magnetic field and is capable of generating electric fields of 7.8 kV/m at 10 m correlating to 4.2 MW of RF power with pulse repetition frequencies up to 1 kHz. Beam steering of the array at angles of ±16.7° is also demonstrated, and the associated general radiation pattern is detailed.
High power microwave beam steering based on gyromagnetic nonlinear transmission lines
Romanchenko, I. V., E-mail: riv@lfe.hcei.tsc.ru; Rostov, V. V.; Gunin, A. V.; Konev, V. Yu. [Institute of high current electronics SB RAS, Akademichesky 2/3, 634055, Tomsk (Russian Federation)
2015-06-07
We demonstrate electronically controlled beam steering by high power RF pulses produced by two gyromagnetic nonlinear transmission lines (NLTLs) connected to a one high voltage driver. Each NLTL is capable of producing several ns RF pulses with peak power from 50 to 700 MW (6% standard deviation) at frequencies from 0.5 to 1.7 GHz (1% standard deviation) with 100 Hz repetition rate. Using a helix antenna allows irradiating of RF pulses with almost circular polarization and 350 MW maximum peak power, which corresponds to 350 kV effective potential of radiation. At the installation of two identical channels, we demonstrate the possibility of beam steering within ±15° in the horizontal plane by coherent RF pulses with circular polarization at 1.0 GHz center frequency. Fourfold increase in the power flux density for in-phase irradiation of RF pulses is confirmed by comparison with one-channel operation.
Distal Radius Fracture (Broken Wrist)
.org Distal Radius Fracture (Broken Wrist) Page ( 1 ) The radius is the larger of the two bones of the forearm. The ... the distal end. A fracture of the distal radius occurs when the area of the radius near ...
Umamaheswari, C.; sundar, D. Shanmuga; Raja, A. Sivanantha
2017-01-01
Three port optical circulators are designed predicated on two dimensional triangular lattice photonic crystals and examined with different size of regular (circular) and irregular (triangular) ferrite posts, through the structure optimization and exploration of defect mode coupling. Ferrite, a special type of highly permeable and low-loss magnetic material, which is anisotropic when biased by a much larger static magnetic field is modeled and the gyromagnetic property of the same is investigated. According to theoretical analysis, the optimized geometry structure can make the non-reciprocal transmission of electromagnetic waves accompanying a high caliber isolation and low insertion loss with the avail of ferrite post inserted at the center of the joint. In order to minimize the reflections in the isolated port at the nominal frequencies, the scaling of ferrite post is implemented by defining S parameter. The structural optimization and the calculation of tensor elements of the anisotropic medium is executed by the finite element method. Moreover, the further study shows the importance of scaling the magneto-photonic material and the way it affects the transmission and isolation of the structured contrivance. Numerical simulations are performed to manifest the attainability and the characteristics of the designed circulators. Finally the triangular ferrite post with the scale of 0.518 makes the non-reciprocal transmission of electromagnetic waves with the minimum insertion loss at the normalized frequency range of 191.6 GHz which benefits from a broad operational bandwidth. This optimized device can realize the operations of splitting, routing and isolation and have good technological compatibility for chip level integration into Photonic Integrated Circuits.
Downie E. J.
2016-01-01
Full Text Available The proton radius puzzle is the difference between the proton radius as measured with electron scattering and in the excitation spectrum of atomic hydrogen, and that measured with muonic hydrogen spectroscopy. Since the inception of the proton radius puzzle in 2010 by the measurement of Pohl et al.[1], many possible resolutions to the puzzle have been postulated, but, to date, none has been generally accepted. New data are therefore necessary to resolve the issue. We briefly review the puzzle, the proposed solutions, and the new electron scattering and spectroscopy experiments planned and underway. We then introduce the MUSE experiment, which seeks to resolve the puzzle by simultaneously measuring elastic electron and muon scattering on the proton, in both charge states, thereby providing new information to the puzzle. MUSE addresses issues of two-photon effects, lepton universality and, possibly, new physics, while providing simultaneous form factor, and therefore radius, measurements with both muons and electrons.
Effective Cleaning Radius Studies
Churnetski, B.V.
2001-10-15
This report discusses results of testing done in the Savannah River Laboratory half tank and full tank mockup facilities using kaolin clay slurries and the relationship between cleaning radius and pump and slurry characteristics.
Stevanovic, Dragan
2015-01-01
Spectral Radius of Graphs provides a thorough overview of important results on the spectral radius of adjacency matrix of graphs that have appeared in the literature in the preceding ten years, most of them with proofs, and including some previously unpublished results of the author. The primer begins with a brief classical review, in order to provide the reader with a foundation for the subsequent chapters. Topics covered include spectral decomposition, the Perron-Frobenius theorem, the Rayleigh quotient, the Weyl inequalities, and the Interlacing theorem. From this introduction, the
Low-energy effective field theory of superfluid 3He-B and its gyromagnetic and Hall responses
Fujii, Keisuke
2016-01-01
The low-energy physics of a superfluid 3He-B is governed by Nambu-Goldstone bosons resulting from its characteristic symmetry breaking pattern. Here we construct an effective field theory at zero temperature consistent with all available symmetries in curved space, which are the U(1) phase x SU(2) spin x SO(3) orbital gauge invariance and the nonrelativistic general coordinate invariance, up to the next-to-leading order in a derivative expansion. The obtained low-energy effective field theory is capable of predicting gyromagnetic responses of the superfluid 3He-B, such as a magnetization generated by a rotation and an orbital angular momentum generated by a magnetic field, in a model-independent and nonperturbative way. We furthermore show that the stress tensor exhibits a dissipationless Hall viscosity with coefficients uniquely fixed by the orbital angular momentum density, which manifests itself as an elliptical polarization of sound wave with an induced transverse component.
Crivelli, P.; Cooke, D.; Heiss, M. W.
2016-09-01
The upcoming operation of the extra low energy antiprotons ring at CERN, the upgrade of the antiproton decelerator (AD), and the installation in the AD hall of an intense slow positron beam with an expected flux of 1 08 e+ /s will open the possibility for new experiments with antihydrogen (H ¯). Here we propose a scheme to measure the Lamb shift of H ¯. For four months of data taking, we anticipate an uncertainty of 100 ppm. This will provide a test of C P T and the first determination of the antiproton charge radius at the level of 10%.
Gusev, A. I.; Pedos, M. S.; Rukin, S. N.; Timoshenkov, S. P.
2017-07-01
In this work, experiments were made in which gyromagnetic nonlinear transmission line (NLTL) operates as a peak power amplifier of the input pulse. At such an operating regime, the duration of the input pulse is close to the period of generated oscillations, and the main part of the input pulse energy is transmitted only to the first peak of the oscillations. Power amplification is achieved due to the voltage amplitude of the first peak across the NLTL output exceeding the voltage amplitude of the input pulse. In the experiments, the input pulse with an amplitude of 500 kV and a half-height pulse duration of 7 ns is applied to the NLTL with a natural oscillation frequency of ˜300 MHz. At the output of the NLTL in 40 Ω coaxial transmission line, the pulse amplitude is increased to 740 kV and the pulse duration is reduced to ˜2 ns, which correspond to power amplification of the input pulse from ˜6 to ˜13 GW. As a source of input pulses, a solid-state semiconductor opening switch generator was used, which allowed carrying out experiments at pulse repetition frequency up to 1 kHz in the burst mode of operation.
Turnaround radius in modified gravity
Faraoni, Valerio
2015-01-01
In an accelerating universe in General Relativity there is a maximum radius above which a shell of test particles cannot collapse, but is dispersed by the cosmic expansion. This radius could be used in conjunction with observations of large structures to constrain the equation of state of the universe. We extend the concept of turnaround radius to modified theories of gravity for which the gravitational slip is non-vanishing.
Magnetic Radius of the Deuteron
Afanasiev, A V; Trubnikov, S V; Afanasev, Andrei V; Trubnikov, S V
1998-01-01
The root-mean square radius of the deuteron magnetic moment distribution, $ r_{Md}$, is calculated for several realistic models of the $NN$--interaction. For the Paris potential the result is $r_{Md} = 2.312 \\pm 0.010 $ fm. The dependence of $r_{Md} $ on the choice of $NN$ model, relativistic effects and meson exchange currents is investigated. The experimental value of $r_{Md}$ is also considered. The necessity of new precise measurements of the deuteron magnetic form factor at low values of $Q^2$ is stressed.
The convexity radius of a Riemannian manifold
Dibble, James
2014-01-01
The ratio of convexity radius over injectivity radius may be made arbitrarily small within the class of compact Riemannian manifolds of any fixed dimension at least two. This is proved using Gulliver's method of constructing manifolds with focal points but no conjugate points. The approach is suggested by a characterization of the convexity radius that resembles a classical result of Klingenberg about the injectivity radius.
Sharp Upper and Lower Bounds for the Laplacian Spectral Radius and the Spectral Radius of Graphs
Ji-ming Guo
2008-01-01
In this paper, sharp upper bounds for the Laplacian spectral radius and the spectral radius of graphs are given, respectively. We show that some known bounds can be obtained from our bounds. For a bipartite graph G, we also present sharp lower bounds for the Laplacian spectral radius and the spectral radius,respectively.
Mirror with thermally controlled radius of curvature
Neil, George R.; Shinn, Michelle D.
2010-06-22
A radius of curvature controlled mirror for controlling precisely the focal point of a laser beam or other light beam. The radius of curvature controlled mirror provides nearly spherical distortion of the mirror in response to differential expansion between the front and rear surfaces of the mirror. The radius of curvature controlled mirror compensates for changes in other optical components due to heating or other physical changes. The radius of curvature controlled mirror includes an arrangement for adjusting the temperature of the front surface and separately adjusting the temperature of the rear surface to control the radius of curvature. The temperature adjustment arrangements can include cooling channels within the mirror body or convection of a gas upon the surface of the mirror. A control system controls the differential expansion between the front and rear surfaces to achieve the desired radius of curvature.
Puzzling out the proton radius puzzle
Mihovilovič Miha
2014-01-01
Full Text Available The discrepancy between the proton charge radius extracted from the muonic hydrogen Lamb shift measurement and the best present value obtained from the elastic scattering experiments, remains unexplained and represents a burning problem of today’s nuclear physics: after more than 50 years of research the radius of a basic constituent of matter is still not understood. This paper presents a summary of the best existing proton radius measurements, followed by an overview of the possible explanations for the observed inconsistency between the hydrogen and the muonic-hydrogen data. In the last part the upcoming experiments, dedicated to remeasuring the proton radius, are described.
Puzzling out the proton radius puzzle
Mihovilovič, M.; Merkel, H.; Weber, A. [Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, Johann-Joachim-Becher-Weg 45, 55128 Mainz (Germany)
2016-01-22
The discrepancy between the proton charge radius extracted from the muonic hydrogen Lamb shift measurement and the best present value obtained from the elastic scattering experiments, remains unexplained and represents a burning problem of today’s nuclear physics: after more than 50 years of research the radius of a basic constituent of matter is still not understood. This paper presents a summary of the best existing proton radius measurements, followed by an overview of the possible explanations for the observed inconsistency between the hydrogen and the muonic-hydrogen data. In the last part the upcoming experiments, dedicated to remeasuring the proton radius, are described.
On the radius constants for classes of analytic functions
Ali, Rosihan M.; Jain, Naveen; Ravichandran, V.
2012-01-01
Radius constants for several classes of analytic functions on the unit disk are obtained. These include the radius of starlikeness of a positive order, radius of parabolic starlikeness, radius of Bernoulli lemniscate starlikeness, and radius of uniform convexity. In the main, the radius constants obtained are sharp. Conjectures on the non-sharp constants are given.
Finite Larmor Radius Effects to Arbitrary Order
Knorr, G.; Hansen, F.R.; Lynov, Jens-Peter
1988-01-01
A representation of a finite Larmor radius plasma is proposed, which permits the transition rL → ∞ without becoming mathematically ill-posed. It is being used in a two-dimensional guiding center plasma spectral code and may have useful analytical applications. The ions are represented as guiding...... centers and the Larmor radius is averaged analytically for every Fourier-mode. Finite Larmor radius densities and velocities are thus obtained from guiding center quantities by application of a filter in wave vector space....
Mass-radius relationships in icy satellites
Lupo, M. J.; Lewis, J. S.
1979-01-01
Using published laboratory data for H2O ice, a modeling technique was developed by which the bulk density, density and temperature profile, rotational moment of inertia, central pressure, and location of the rock-ice interface can all be obtained as a function of the radius, the heliocentric distance, and the silicate composition. Models of the interiors of Callisto, Ganymede, Europa, Rhea, and Titan are given, consistent with present mass and radius data. The radius and mass of spheres of ice under self-gravitation for two different temperature classes are given (103 and 77 deg K). Measurements of mass, radius and I/MR2 by spacecraft can be interpreted by this model to yield substantial information about the internal structure and the ice/rock ratio of the icy satellites of Jupiter and Saturn.
Inside the Bondi radius of M87
Russell, H R; McNamara, B R; Broderick, A E
2015-01-01
Chandra X-ray observations of the nearby brightest cluster galaxy M87 resolve the hot gas structure across the Bondi accretion radius of the central supermassive black hole, a measurement possible in only a handful of systems but complicated by the bright nucleus and jet emission. By stacking only short frame-time observations to limit pileup, and after subtracting the nuclear PSF, we analysed the X-ray gas properties within the Bondi radius at 0.12-0.22 kpc (1.5-2.8 arcsec), depending on the black hole mass. Within 2 kpc radius, we detect two significant temperature components, which are consistent with constant values of 2 keV and 0.9 keV down to 0.15 kpc radius. No evidence was found for the expected temperature increase within ~0.25 kpc due to the influence of the SMBH. Within the Bondi radius, the density profile is consistent with $\\rho\\propto r^{-1}$. The lack of a temperature increase inside the Bondi radius suggests that the hot gas structure is not dictated by the SMBH's potential and, together with...
Solar Radius at Sub-Terahertz Frequencies
Menezes, Fabian; Valio, Adriana
2017-10-01
The visible surface of the Sun, or photosphere, is defined as the solar radius in the optical spectrum range located at 696,000 km (Cox et al. (Ed. 2015)). However, as the altitude increases, the dominant electromagnetic radiation is emitted at other frequencies. Our aim is to measure the solar radius at frequencies of 212 GHz and 405 GHz through out a solar cycle and, therefore, the altitude where these emissions are generated and that variation along the years. Also we tried to verify the the radius dependence on the solar activity cycle, which can be a good indicator of the changes that occur in the atmosphere structure. For this, we used data obtained by the Submillimetric Solar Telescope (SST) created from daily scans made by SST from 1990 to 2015. From these scans a 2D map of the solar disk was constructed. The solar radius is then determined by adjusting a circumference to the points where the brightness is half of the quiet Sun level, which is set as the most common temperature value in the solar map, i.e., the mode of the temperature distribution. Thus, we determined the solar radius at 212 and 405 GHz and the altitude of the emissions respectively. For 212 GHz, we obtained a radius of 976.5''+/-8'' (707+/-4 Mm), whereas for 405 GHz, we obtained 975.0''+/-8'' (707+/-5 Mm). optical spectrum range
Measuring Neutron Star Mass and Radius with Three Mass-Radius Relations
Zhang, C M; Kojima, Y; Chang, H K; Xu, R X; Li, X D; Zhang, B; Kiziltan, B
2006-01-01
We propose to determine the mass and the radius of a neutron star (NS) using three measurable mass-radius relationships, namely the ``apparent'' radius inferred from neutron star thermal emission, the gravitational redshift inferred from the absorption lines, as well as the averaged stellar mass density inferred from the orbital Keplerian frequency derived from the kilohertz quasi periodic oscillation (kHz QPO) data. We apply the method to constrain the NS mass and the radius of the X-ray sources, 1E 1207.4-5209, Aql X-1 and EXO 0748-676.
Nuclear charge radius of $^8$He
Müller, P; Villari, A C C; Alcantara-Nunez, J A; Alves-Conde, R; Bailey, K; Drake, G W F; Dubois, M; Eleon, C; Gaubert, G; Holt, R J; Janssens, R V F; Lecesne, N; Lu, Z -T; O'Connor, T P; Saint-Laurent, M -G; Thomas, J -C; Wang, L -B
2008-01-01
The root-mean-square (rms) nuclear charge radius of ^8He, the most neutron-rich of all particle-stable nuclei, has been determined for the first time to be 1.93(3) fm. In addition, the rms charge radius of ^6He was measured to be 2.068(11) fm, in excellent agreement with a previous result. The significant reduction in charge radius from ^6He to ^8He is an indication of the change in the correlations of the excess neutrons and is consistent with the ^8He neutron halo structure. The experiment was based on laser spectroscopy of individual helium atoms cooled and confined in a magneto-optical trap. Charge radii were extracted from the measured isotope shifts with the help of precision atomic theory calculations.
Critical bubble radius in solvent sublation
无
2007-01-01
The complex compound of dithizone-Co(Ⅱ) was separated and concentrated from the aqueous phase to n-octanol by solvent sublation. From the analysis of the coalescence behavior of bubbles on water-organic interface, the conception of critical bubble radius was proposed, and the value of the critical bubble radius in the water-octanol system was obtained: 1.196 × 10-3 m. The simulation of the mathematical model using CBR and experimental data is completed with perfect results, and the simulation of the mathematical model using CBR is very different with the classic one. The analytical results proved that the critical bubble radius should be adequately considered in mathematical model of solvent sublation.
Relationship Between Thermal Tides and Radius Excess
Socrates, Aristotle
2013-01-01
Close-in extrasolar gas giants -- the hot Jupiters -- display departures in radius above the zero-temperature solution, the radius excess, that are anomalously high. The radius excess of hot Jupiters follows a relatively close relation with thermal tidal tidal torques and holds for ~ 4-5 orders of magnitude in a characteristic thermal tidal power in such a way that is consistent with basic theoretical expectations. The relation suggests that thermal tidal torques determine the global thermodynamic and spin state of the hot Jupiters. On empirical grounds, it is shown that theories of hot Jupiter inflation that invoke a constant fraction of the stellar flux to be deposited at great depth are, essentially, falsified.
A Maximum Radius for Habitable Planets.
Alibert, Yann
2015-09-01
We compute the maximum radius a planet can have in order to fulfill two constraints that are likely necessary conditions for habitability: 1- surface temperature and pressure compatible with the existence of liquid water, and 2- no ice layer at the bottom of a putative global ocean, that would prevent the operation of the geologic carbon cycle to operate. We demonstrate that, above a given radius, these two constraints cannot be met: in the Super-Earth mass range (1-12 Mearth), the overall maximum that a planet can have varies between 1.8 and 2.3 Rearth. This radius is reduced when considering planets with higher Fe/Si ratios, and taking into account irradiation effects on the structure of the gas envelope.
Management of Malunions of the Distal Radius
Yaniel Truffin Rodriguez; Osmany Pérez Martínez; Rafael Esmandy Gómez Arregoitía; Indira L. Gómez Gil
2015-01-01
Fractures of the distal radius often present with a group of major complications. Of these, malunion is one of the most disabling. Its management through salvage procedures is essential for its correction. The case of a 60-year-old healthy woman of urban origin treated at the Dr. Gustavo Aldereguía Lima University General Hospital in Cienfuegos because of a malunion of the distal end of the left radius as a result of a previous Colles' fracture is presented. The patient complained of severe p...
Contact radius of stamps in reversible adhesion
无
2011-01-01
A mechanics model is developed for the contact radius of stamps with pyramid tips in transfer printing.This is important to the realization of reversible control of adhesion,which has many important applications,such as climbing robots,medical tapes,and transfer printing of electronics.The contact radius is shown to scale linearly with the work of adhesion between the stamp and the contacting surface,and inversely with the plane-strain modulus of the stamp. It also depends on the cone angle and tip radiu...
Study Application of RADIUS Protocol on Ethernet
GUO Fang; YANG Huan-yu; LI Hong
2004-01-01
This paper presents how to apply the RADIUS (Remote Authentication Dial In User Service)protocol ,which is generally applied to dial-up network, to the authentication & charge of Broad Band accessing control system on Ethernet. It is provided that the Broad Band accessing control system included a self-designed communication protocol is used in communicating between an terminal user and Network Access Server .The interface module on the servers side and the Radius system is also given in this article.
BOREL RADIUS AND T-RADIUS OF THE ALGEBROIDAL FUNCTION IN THE UNIT DISC
Kong Yinying
2012-01-01
Using Ahlfors' theory of covering surface and a type-function,we confirm the existence theorem of a Borel radius and a T-radius for the algebroidal function dealing with multiple values in the unit disc,which briefly extend some results for the algebroidal functions in the complex plane.
Zhang, H; Chen, S; Wang, Z; Guo, Y; Liu, B; Tong, D
2016-07-01
During osteoarticular reconstruction of the distal radius with the proximal fibula, congruity between the two articular surfaces is an important factor in determining the quality of the outcome. In this study, a three-dimensional model and a coordinate transformation algorithm were developed on computed tomography scanning. Articular surface matching was performed and parameters for the optimal position were determined quantitatively. The mean radii of best-fit spheres of the articular surfaces of the distal radius and proximal fibula were compared quantitatively. The radial inclination and volar tilt following reconstruction by an ipsilateral fibula graft, rather than the contralateral, best resembles the values of the native distal radius. Additionally, the ipsilateral fibula graft reconstructed a larger proportion of the distal radius articular surface than did the contralateral. The ipsilateral proximal fibula graft provides a better match for the reconstruction of the distal radius articular surface than the contralateral, and the optimal position for graft placement is quantitatively determined.
Mass and Radius of Neutron Stars Constrained by Photospheric Radius Expansion X-ray Bursts
Kwak, Kyujin; Kim, Myungkuk; Kim, Young-Min; Lee, Chang-Hwan
Simultaneous measurement of mass and radius of a neutron star is important because it provides strong constraint on the equation of state for nuclear matter inside a neutron star. Type I X-ray Bursts (XRBs) that have been observed in low-mass X-ray binaries sometimes show photospheric radius expansion (PRE). By combining observed fluxes, X-ray spectra, and distances of PRE XRBs and using a statistical analysis, it is possible to simultaneously constrain the mass and radius of a neutron star. However, the mass and radius of a neutron star estimated in this method depends on the opacity of accreted material. We investigate the effect of the opacity on the mass and radius estimation by taking into account the cases that the hydrogen mass fraction of accreted material has narrowly-distributed values. We present preliminary results that are investigated with three different values of hydrogen mass fraction and compare our results with previous studies.
Denseness of Numerical Radius Attaining Holomorphic Functions
Lee HanJu
2009-01-01
Full Text Available We study the density of numerical radius attaining holomorphic functions on certain Banach spaces using the Lindenstrauss method. In particular, it is shown that if a complex Banach space is locally uniformly convex, then the set of all numerical attaining elements of is dense in .
Denseness of Numerical Radius Attaining Holomorphic Functions
Han Ju Lee
2009-01-01
Full Text Available We study the density of numerical radius attaining holomorphic functions on certain Banach spaces using the Lindenstrauss method. In particular, it is shown that if a complex Banach space X is locally uniformly convex, then the set of all numerical attaining elements of A(BX:X is dense in A(BX:X.
Improved KAM estimates for the Siegel radius
Liverani, C.; Turchetti, G.
1986-12-01
For the Siegel center problem the authors explore the possibility of improving the KAM estimates, with a view to possible extensions to Hamiltonian systems. The use of a suitable norm and explicit perturbative computations allow estimates to within a factor 2 of the Siegel radius for the quadratic map.
Mass-radius relationships for exoplanets
Swift, Damian; Hicks, Damien; Hamel, Sebastien; Caspersen, Kyle; Schwegler, Eric; Collins, Gilbert; Ackland, Graeme
2010-01-01
For planets other than Earth, and in particular for exoplanets, interpretation of the composition and structure depends largely on a comparison of the mass and radius with the composition expected given their distance from the parent star. The composition implies a mass-radius relation for different layers within the planet, which is based heavily on equations of state calculated from electronic structure theory and measured experimentally on Earth. We summarize current techniques for predicting and measuring equations of state, and calculate mass-radius relations for key materials for which the equation of state is reasonably well established, and for Fe-rock combinations. The relations are compared with the observed masses and radii of planets and exoplanets, broadly supporting recent inferences about exoplanet structures. CoRoT-7b probably has a rocky mantle over an Fe-based core. The core is likely to be proportionately smaller than the Earth's. GJ 1214b lies between the mass-radius curves for H_2Oand CH_...
Proton radius from electron scattering data
Higinbotham, Douglas W. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Kabir, Al Amin; Lin, Vincent; Meekins, David; Norum, Blaine; Sawatzky, Brad
2016-05-01
Background: The proton charge radius extracted from recent muonic hydrogen Lamb shift measurements is significantly smaller than that extracted from atomic hydrogen and electron scattering measurements. The discrepancy has become known as the proton radius puzzle. Purpose: In an attempt to understand the discrepancy, we review high-precision electron scattering results from Mainz, Jefferson Lab, Saskatoon, and Stanford. Methods: We make use of stepwise regression techniques using the F test as well as the Akaike information criterion to systematically determine the predictive variables to use for a given set and range of electron scattering data as well as to provide multivariate error estimates. Results: Starting with the precision, low four-momentum transfer (Q2) data from Mainz (1980) and Saskatoon (1974), we find that a stepwise regression of the Maclaurin series using the F test as well as the Akaike information criterion justify using a linear extrapolation which yields a value for the proton radius that is consistent with the result obtained from muonic hydrogen measurements. Applying the same Maclaurin series and statistical criteria to the 2014 Rosenbluth results on GE from Mainz, we again find that the stepwise regression tends to favor a radius consistent with the muonic hydrogen radius but produces results that are extremely sensitive to the range of data included in the fit. Making use of the high-Q2 data on GE to select functions which extrapolate to high Q2, we find that a Padé (N=M=1) statistical model works remarkably well, as does a dipole function with a 0.84 fm radius, GE(Q2)=(1+Q2/0.66GeV2)−2. Conclusions: Rigorous applications of stepwise regression techniques and multivariate error estimates result in the extraction of a proton charge radius that is consistent with the muonic hydrogen result of 0.84 fm; either from linear extrapolation of the extremely-low-Q2 data or by use of the Padé approximant for extrapolation using a larger range of
MASS-RADIUS RELATIONSHIPS FOR EXOPLANETS
Swift, D. C.; Eggert, J. H.; Hicks, D. G.; Hamel, S.; Caspersen, K.; Schwegler, E.; Collins, G. W. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California, CA 94550 (United States); Nettelmann, N. [Institut fuer Physik, Universitaet Rostock, D-18051 Rostock (Germany); Ackland, G. J. [Centre for Science at Extreme Conditions, School of Physics, University of Edinburgh, Edinburgh EH9 3JZ (United Kingdom)
2012-01-01
For planets other than Earth, particularly exoplanets, interpretation of the composition and structure depends largely on comparing the mass and radius with the composition expected given their distance from the parent star. The composition implies a mass-radius relation which relies heavily on equations of state calculated from electronic structure theory and measured experimentally on Earth. We lay out a method for deriving and testing equations of state, and deduce mass-radius and mass-pressure relations for key, relevant materials whose equation of state (EOS) is reasonably well established, and for differentiated Fe/rock. We find that variations in the EOS, such as may arise when extrapolating from low-pressure data, can have significant effects on predicted mass-radius relations and on planetary pressure profiles. The relations are compared with the observed masses and radii of planets and exoplanets, broadly supporting recent inferences about exoplanet structures. Kepler-10b is apparently 'Earth-like', likely with a proportionately larger core than Earth's, nominally 2/3 of the mass of the planet. CoRoT-7b is consistent with a rocky mantle over an Fe-based core which is likely to be proportionately smaller than Earth's. GJ 1214b lies between the mass-radius curves for H{sub 2}O and CH{sub 4}, suggesting an 'icy' composition with a relatively large core or a relatively large proportion of H{sub 2}O. CoRoT-2b is less dense than the hydrogen relation, which could be explained by an anomalously high degree of heating or by higher than assumed atmospheric opacity. HAT-P-2b is slightly denser than the mass-radius relation for hydrogen, suggesting the presence of a significant amount of matter of higher atomic number. CoRoT-3b lies close to the hydrogen relation. The pressure at the center of Kepler-10b is 1.5{sup +1.2}{sub -1.0} TPa. The central pressure in CoRoT-7b is probably close to 0.8 TPa, though may be up to 2 TPa. These
The Proton Radius from Electron Scattering Data
Higinbotham, Douglas W; Lin, Vincent; Meekins, David; Norum, Blaine; Sawatzky, Brad
2015-01-01
In an attempt to understand the discrepancy between the proton radius determined the muonic hydrogen Lamb shift and elastic electron-proton scattering measurements, we carefully review two classic, high precision electron scattering charge form factor, ${G_E}$, results. Upon examination, it was noted that the covariance matrices of common three parameter fits show large parameter correlations. Thus, we reanalyzed the classic data guided by statistical constraints and found low $q^2$, two-parameter fits were actually consistent with muonic hydrogen results. By subsequently including the highest measured values of ${G_E}(q^2)$ in the fits, we found that a dipole function, $G_E(q^2) = ( 1 + q^2/0.66[\\rm{GeV}^2])^{-2}$, with the muonic hydrogen radius, 0.84087(39) fm, not only describes the low $q^2$ electron scattering data, but also describes the highest measured $q^2$ $G_E$ values.
苏佳灿; 张春才; 禹宝庆; 许硕贵; 王家林; 纪方; 张雪松; 吴建国; 王保华; 薛召军; 丁祖泉
2003-01-01
Objective: To study the memory biomechanical character of anatomic distal radius Nitinol memory connector (DRMC) in treating distal radius fracture. Methods: Establishing three dimensional model and finite element analysis, we calculated the stress in and around the fracture faces when distal radius fracture was fixated with DRMC. Results: Axial holding stress produced by holding part of DRMC on distal radius was 14.66 MPa. The maximum stress of holding part was 40-70 MPa, the minimum stress was 3-7 MPa,and the stress of compression part was 20-40 MPa. Conclusion: The distribution of stress produced by DRMC around the fracture line is reasonable, and axial holding stress can help stabilize fracture during earlier period. The existence of longitudal compression and memory effect can transfer fixated disused section into developed section and enhance fracture healing.
Cost Effective RADIUS Authentication for Wireless Clients
Alexandru ENACEANU
2010-12-01
Full Text Available Network administrators need to keep administrative user information for each network device, but network devices usually support only limited functions for user management. WLAN security is a modern problem that needs to be solved and it requires a lot of overhead especially when applied to corporate wireless networks. Administrators can set up a RADIUS server that uses an external database server to handle authentication, authorization, and accounting for network security issues.
Phacoemulsification efficiency with a radiused phaco tip.
Gupta, Isha; Zaugg, Brian; Stagg, Brian C; Barlow, William R; Pettey, Jeff H; Jensen, Jason D; Kirk, Kevin R; Olson, Randall J
2014-05-01
To evaluate radiused and nonradiused phacoemulsification tips to determine which tip is more efficient in removal of lens fragments using 3 ultrasound (US) modalities. John A. Moran Eye Center Laboratories, University of Utah, Salt Lake City, Utah, USA. Experimental study. Porcine lens nuclei were formalin-soaked for 2 hours or 3 hours and then divided into 2.0 mm cubes. Thirty-degree, 0.9 mm beveled radiused tips and nonradiused tips were used with torsional, transverse, and micropulsed US modalities. Bent tips were used with torsional and transversal US, and straight tips were used with micropulsed US. Efficiency (time to lens removal) and chatter (number of lens fragment repulsions from the tip) were determined. The mean phacoemulsification efficiency was statistically significantly decreased (increased time for removal) with the radiused tip compared with the nonradiused tip for torsional US only (2-hour soaked lenses: 2.14 seconds ± 1.94 [SD] versus 1.18 ± 0.69 seconds [P tip showed decreased efficiency with torsional US only. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2014 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.
On the radius of habitable planets
Alibert, Yann
2013-01-01
The conditions that a planet must fulfill to be habitable are not precisely known. However, it is comparatively easier to define conditions under which a planet is very likely not habitable. Finding such conditions is important as it can help select, in an ensemble of potentially observable planets, which ones should be observed in greater detail for characterization studies. Assuming, as in the Earth, that the presence of a C-cycle is a necessary condition for long-term habitability, we derive, as a function of the planetary mass, a radius above which a planet is likely not habitable. We compute the maximum radius a planet can have to fulfill two constraints: surface conditions compatible with the existence of liquid water, and no ice layer at the bottom of a putative global ocean. We demonstrate that, above a given radius, these two constraints cannot be met. We compute internal structure models of planets, using a five-layer model (core, inner mantle, outer mantle, ocean, and atmosphere), for different mas...
Crivelli, P; Heiss, M W
2016-01-01
The upcoming operation of the Extra Low ENergy Antiprotons (ELENA) ring at CERN, the upgrade of the anti-proton decelerator (AD), and the installation in the AD hall of an intense slow positron beam with an expected flux of $10^{8}$ e$^+$/s will open the possibility for new experiments with anti-hydrogen ($\\bar{\\text{H}}$). Here we propose a scheme to measure the Lamb shift of $\\bar{\\text{H}}$. For a month of data taking, we anticipate an uncertainty of 100 ppm. This will provide a test of CPT and the first determination of the anti-proton charge radius at the level of 10%.
Small-radius jets to all orders
Cacciari, Matteo; Soyez, Gregory; Salam, Gavin; Dasgupta, Mrinal
2015-01-01
With hadron colliders continuing to push the boundaries of precision, it is becoming increas ingly important to have a detailed understanding of the subtleties appearing at smaller values of the jet radius R. We present a method to resum all leading logarithmic terms, a'.; Inn R, using a generating functional approach, as was recently discussed in Ref. 1. We study a variety of observables, such as the inclusive jet spectrum and jet vetoes for Higgs physics, and show that small-R effects can be sizeable. Finally, we compare our calculations to existing ALICE data, and show good agreement.
Are classifications of proximal radius fractures reproducible?
dos Santos João BG
2009-10-01
Full Text Available Abstract Background Fractures of the proximal radius need to be classified in an appropriate and reproducible manner. The aim of this study was to assess the reliability of the three most widely used classification systems. Methods Elbow radiographs images of patients with proximal radius fractures were classified according to Mason, Morrey, and Arbeitsgemeinschaft für osteosynthesefragen/Association for the Study of Internal Fixation (AO/ASIF classifications by four observers with different experience with this subject to assess their intra- and inter-observer agreement. Each observer analyzed the images on three different occasions on a computer with numerical sequence randomly altered. Results We found that intra-observer agreement of Mason and Morrey classifications were satisfactory (κ = 0.582 and 0.554, respectively, while the AO/ASIF classification had poor intra-observer agreement (κ = 0.483. Inter-observer agreement was higher in the Mason (κ = 0.429-0.560 and Morrey (κ = 0.319-0.487 classifications than in the AO/ASIF classification (κ = 0.250-0.478, which showed poor reliability. Conclusion Inter- and intra-observer agreement of the Mason and Morey classifications showed overall satisfactory reliability when compared to the AO/ASIF system. The Mason classification is the most reliable system.
Genetics Home Reference: thrombocytopenia-absent radius syndrome
... Genetics Home Health Conditions TAR syndrome thrombocytopenia-absent radius syndrome Enable Javascript to view the expand/collapse ... PDF Open All Close All Description Thrombocytopenia-absent radius (TAR) syndrome is characterized by the absence of ...
Mass-radius relations of white dwarfs at finite temperatures
Boshkayev, Kuantay; Rueda, Jorge A.; Ruffini, Remo; Zhami, Bakytzhan; Kalymova, Zhanerke; Balgimbekov, Galymdin
2016-01-01
We construct mass-radius relations of white dwarfs taking into account the effects of rotation and finite temperatures. We compare and contrast the theoretical mass-radius relations with observational data.
Spectral Radius of Hamiltonian Planar Graphs and Outerplanar Graphs
周建; 林翠琴; 胡冠章
2001-01-01
The spectral radius is an important parameter of a graph related to networks. A method forestimating the spectral radius of each spanning subgraph is used to prove that the spectral radius of aHamiltonian planar graph of order n ≥ 4 is less than or equal toand the spectral radius of theouterplanar graph of order n ≥ 6 is less than or equal to, which are improvements overprevious results. A direction for further study is then suggested.``
21 CFR 886.1450 - Corneal radius measuring device.
2010-04-01
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Corneal radius measuring device. 886.1450 Section... (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1450 Corneal radius measuring device. (a) Identification. A corneal radius measuring device is an AC-powered device intended to...
Ultrasound-Assisted Distal Radius Fracture Reduction
Socransky, Steve; Skinner, Andrew; Bromley, Mark; Smith, Andrew; Anawati, Alexandre; Middaugh, Jeff; Ross, Peter
2016-01-01
Introduction Closed reduction of distal radius fractures (CRDRF) is a commonly performed emergency department (ED) procedure. The use of point-of-care ultrasound (PoCUS) to diagnose fractures and guide reduction has previously been described. The primary objective of this study was to determine if the addition of PoCUS to CRDRF changed the perception of successful initial reduction. This was measured by the rate of further reduction attempts based on PoCUS following the initial clinical determination of achievement of best possible reduction. Methods We performed a multicenter prospective cohort study, using a convenience sample of adult ED patients presenting with a distal radius fracture to five Canadian EDs. All study physicians underwent standardized PoCUS training for fractures. Standard clinically-guided best possible fracture reduction was initially performed. PoCUS was then used to assess the reduction adequacy. Repeat reduction was performed if deemed indicated. A post-reduction radiograph was then performed. Clinician impression of reduction adequacy was scored on a 5 point Likert scale following the initial clinically-guided reduction and following each PoCUS scan and the post-reduction radiograph. Results There were 131 patients with 132 distal radius fractures. Twelve cases were excluded prior to analysis. There was no significant difference in the assessment of the initial reduction status by PoCUS as compared to the clinical exam (mean score: 3.8 vs. 3.9; p = 0.370; OR 0.89; 95% CI 0.46 to 1.72; p = 0.87). Significantly fewer cases fell into the uncertain category with PoCUS than with clinical assessment (2 vs 12; p = 0.008). Repeat reduction was performed in 49 patients (41.2%). Repeat reduction led to a significant improvement (p < 0.001) in the PoCUS determined adequacy of reduction (mean score: 4.3 vs 3.1; p < 0.001). In this group, the odds ratio for adequate vs. uncertain or inadequate reduction assessment using PoCUS was 12.5 (95% CI 3
Understanding the mass-radius relation for sub-Neptunes: radius as a proxy for composition
Lopez, Eric D.; Fortney, Jonathan J. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States)
2014-09-01
Transiting planet surveys like Kepler have provided a wealth of information on the distribution of planetary radii, particularly for the new populations of super-Earth- and sub-Neptune-sized planets. In order to aid in the physical interpretation of these radii, we compute model radii for low-mass rocky planets with hydrogen-helium envelopes. We provide model radii for planets 1-20 M {sub ⊕}, with envelope fractions 0.01%-20%, levels of irradiation 0.1-1000 times Earth's, and ages from 100 Myr to 10 Gyr. In addition we provide simple analytic fits that summarize how radius depends on each of these parameters. Most importantly, we show that at fixed H/He envelope fraction, radii show little dependence on mass for planets with more than ∼1% of their mass in their envelope. Consequently, planetary radius is to a first order a proxy for planetary composition, i.e., H/He envelope fraction, for Neptune- and sub-Neptune-sized planets. We recast the observed mass-radius relationship as a mass-composition relationship and discuss it in light of traditional core accretion theory. We discuss the transition from rocky super-Earths to sub-Neptune planets with large volatile envelopes. We suggest ∼1.75 R {sub ⊕} as a physically motivated dividing line between these two populations of planets. Finally, we discuss these results in light of the observed radius occurrence distribution found by Kepler.
Mass-radius relationships of rocky exoplanets
Sohl, F; Rauer, H
2012-01-01
Mass and radius of planets transiting their host stars are provided by radial velocity and photometric observations. Structural models of solid exoplanet interiors are then constructed by using equations of state for the radial density distribution, which are compliant with the thermodynamics of the high-pressure limit. However, to some extent those structural models suffer from inherent degeneracy or non-uniqueness problems owing to a principal lack of knowledge of the internal differentiation state and/or the possible presence of an optically thick atmosphere. We here discuss the role of corresponding measurement errors, which adversely affect determinations of a planet's mean density and bulk chemical composition. Precise measurements of planet radii will become increasingly important as key observational constraints for radial density models of individual solid low-mass exoplanets or super-Earths.
Physeal arrest of the distal radius.
Abzug, Joshua M; Little, Kevin; Kozin, Scott H
2014-06-01
Fractures of the distal radius are among the most common pediatric fractures. Although most of these fractures heal without complication, some result in partial or complete physeal arrest. The risk of physeal arrest can be reduced by avoiding known risk factors during fracture management, including multiple attempts at fracture reduction. Athletes may place substantial compressive and shear forces across the distal radial physes, making them prone to growth arrest. Timely recognition of physeal arrest can allow for more predictable procedures to be performed, such as distal ulnar epiphysiodesis. In cases of partial arrest, physeal bar excision with interposition grafting can be performed. Once ulnar abutment is present, more invasive procedures may be required, including ulnar shortening osteotomy or radial lengthening.
On Galaxy Mass-Radius Relationship
Bindoni, D.; Secco, L.; Contini, E.; Caimmi, R.
In the Clausius' virial maximum theory (TCV) [Secco and Bindoni, NewA 14, 567 (2009)] to explain the galaxy Fundamental Plane (FP) a natural explanation follows about the observed relationship between stellar mass and effective radius, M ∗ - r e , for early type galaxies (ETGs). The key of this correlation lies in the deep link which has to exist between cosmology and the existence of the FP. The general strategy consists in using the two-component tensor virial theorem to describe the virial configuration of the baryonic component of mass M B ≃ M ∗ embedded in a dark matter (DM) halo of mass M D at the end of relaxation phase. In a ΛCDM flat cosmology, starting from variance at equivalence epoch, we derive some preliminary theoretical relationships, M ∗ - r e , which are functions of mass ratio m = M D / M B . They appear to be in agreement with the trends extracted from the data of galaxy sample used by [Tortora et al., MNRAS 396, 1132 (2009)].
Experimental study of finite Larmor radius effects
Struve, K.W.
1980-08-01
Linear Z-pinches in Ar, Kr, Xe, N/sub 2/, and He are experimentally studied in regimes where strong finite Larmor radius effects could provide a significant stabilizing effect. Scaling arguments show that for deuterium such a pinch has an electron line density of order 2 x 10/sup 15//cm. For higher Z plasmas a higher line density is allowed, the exact value of which depends on the average ion charge. The pinch is formed by puffing gas axially through the cathode towards the anode of an evacuated pinch chamber. When the gas reaches the anode, the pinch bank is fired. The pinch current rises in 2 to 3 ..mu..sec to a maximum of 100 to 200 kA. The pinch bank capacitance is 900 ..mu..F, and the external inductance is 100 nH. Additionally, the bank is fused to increase dI/dt. The primary diagnostics are a framing camera, a spatially resolved Mach-Zehnder interferometer, and X-ray absorption.
Fragmentation of a Jet with Small Radius
Dai, Lin; Leibovich, Adam K
2016-01-01
In this paper we consider the fragmentation of a parton into a jet with small jet radius $R$. Perturbatively, logarithms of $R$ can appear, which for narrow jets can lead to large corrections. Using soft-collinear effective theory (SCET), we introduce the jet fragmentation function (JFF), which describes the fragmentation of a parton into a jet. We discuss how these objects are related to the standard jet functions. Calculating the JFF to next-to-leading order, we show that these objects satisfy the standard DGLAP evolution equations, with a natural scale that depends upon $R$. By using standard renormalization group evolution, we can therefore resum logarithms of $R$. We further use SCET to prove a factorization theorem where the JFFs naturally appear, for the fragmentation of a hadron within a jet with small $R$. Finally, we also show how this formalism can be used to resum the ratio of jet radii for a subjet to be emitted from within a fat jet.
On the p-norm joint spectral radius
周佳立
2003-01-01
The p-norm joint spectral radius is defined by a bounded collection of square matrices with complex entries and of the same size. In the present paper the author investigates the p-norm joint spectral radius for integers. The method introduced in this paper yields some basic formulas for these spectral radii. The approach used in this paper provides a simple proof of Berger-Wang's relation concerning the ∞-norm joint spectral radius.
On the p-norm joint spectral radius
周佳立
2003-01-01
The p-norm joint spectral radius is defined by a bounded collection of square matrices with complex entries and of the same size. In the present paper the author investigates the p-norm joint spectral radius for integers. The method introduced in this paper yields some basic formulas for these spectral radii. The approach used in this paper provides a simple proof of Berger-Wang' s relation concerning the ∞-norm joint spectral radius.
Applying Occam's Razor To The Proton Radius Puzzle
Higinbotham, Douglas
2016-09-01
Over the past five decades, ever more complex mathematical functions have been used to extract the radius of the proton from electron scattering data. For example, in 1963 the proton radius was extracted with linear and quadratic fits of low Q2 data (Lamb shift measurements.
The Origin of the Ionic-Radius Ratio Rules
Jensen, William B.
2010-01-01
In response to a reader query, this article traces the origins of the ionic-radius ratio rules and their incorrect attribution to Linus Pauling in the chemical literature and to Victor Goldschmidt in the geochemical literature. In actual fact, the ionic-radius ratio rules were first proposed within the context of the coordination chemistry…
Decreasing the spectral radius of a graph by link removals
Van Mieghem, P.; Stevanović, D.; Kuipers, F.; Li, C.; Van de Bovenkamp, R.; Liu, D.; Wang, H.
2011-01-01
The decrease of the spectral radius, an important characterizer of network dynamics, by removing links is investigated. The minimization of the spectral radius by removing m links is shown to be an NP-complete problem, which suggests considering heuristic strategies. Several greedy strategies are co
The minimal spectral radius of graphs with a given diameter
Dam, E.R. van; Kooij, R.E.
2007-01-01
The spectral radius of a graph (i.e., the largest eigenvalue of its corresponding adjacency matrix) plays an important role in modeling virus propagation in networks. In fact, the smaller the spectral radius, the larger the robustness of a network against the spread of viruses. Among all connected g
Numerical Radius Inequalities for Finite Sums of Operators
Mirmostafaee Alireza Kamel
2014-12-01
Full Text Available In this paper, we obtain some sharp inequalities for numerical radius of finite sums of operators. Moreover, we give some applications of our result in estimation of spectral radius. We also compare our results with some known results.
Distal radius fractures: what determines the outcome after surgery?
Teunis, T.
2016-01-01
This thesis addresses current issues in the outcome of operatively treated distal radius fractures. The general aim was to determine factors associated with adverse events, loss of motion, functional limitations, and opioid use after surgery. Injury In 3D complete articular distal radius fracture mo
Return Radius and volume of recrystallized material in Ostwald Ripening
Hausser, Frank
2012-01-01
Within the framework of the LSW theory of Ostwald ripening the amount of volume of the second (solid) phase that is newly formed by recrystallization is investigated. It is shown, that in the late stage, the portion of the newly generated volume formed within an interval from time $t_0$ to $t$ is a certain function of $t/t_0$ and an explicit expression of this volume is given. To achieve this, we introduce the notion of the {\\it return radius} $r(t,t_0)$, which is the unique radius of a particle at time $t_0$ such that this particle has -- after growing and shrinking -- the same radius at time $t$. We derive a formula for the return radius which later on is used to obtain the newly formed volume. Moreover, formulas for the growth rate of the return radius and the recrystallized material at time $t_0$ are derived.
Effects of inlet radius and bell mouth radius on flow rate and sound quality of centrifugal blower
Son, Pham Ngoc; Kim, Jae Won; Byun, S. M. [Sunmoon University, Asan (Korea, Republic of); Ahn, E. Y. [Hanbat National University, Daejeon (Korea, Republic of)
2012-05-15
The effect of inlet radius and bell mouth radius on flow rate of centrifugal blower were numerically simulated using a commercial CFD program, FLUENT. In this research, a total of eight numerical models were prepared by combining different values of bell mouth radii and inlet radii (the cross section of bell mouth was chosen as a circular arc in this research). The frozen rotor method combined with a realizable k-epsilon turbulence model and non-equilibrium wall function was used to simulate the three-dimensional flow inside the centrifugal blowers. The inlet radius was then revealed to have significant impact on flow rate with the maximum difference between analyzed models was about 4.5% while the bell mouth radius had about 3% impact on flow rate. Parallel experiments were carried out to confirm the results of CFD analysis. The CFD results were thereafter validated owning to the good agreement between CFD results and the parallel experiment results. In addition to performance analysis, noise experiments were carried out to analyze the dependence of sound quality on inlet radius and bell mouth radius with different flow rate. The noise experiment results showed that the loudness and sharpness value of different models were quite similar, which mean the inlet radius and the bell mouth radius didn't have a clear impact on sound quality of centrifugal blower.
Thermoconvective vortices in a cylindrical annulus with varying inner radius.
Castaño, D; Navarro, M C; Herrero, H
2014-12-01
This paper shows the influence of the inner radius on the stability and intensity of vertical vortices, qualitatively similar to dust devils and cyclones, generated in a cylindrical annulus non-homogeneously heated from below. Little relation is found between the intensity of the vortex and the magnitude of the inner radius. Strong stable vortices can be found for both small and large values of the inner radius. The Rankine combined vortex structure, that characterizes the tangential velocity in dust devils, is clearly observed when small values of the inner radius and large values of the ratio between the horizontal and vertical temperature differences are considered. A contraction on the radius of maximum azimuthal velocity is observed when the vortex is intensified by thermal mechanisms. This radius becomes then nearly stationary when frictional force balances the radial inflow generated by the pressure drop in the center, despite the vortex keeps intensifying. These results connect with the behavior of the radius of the maximum tangential wind associated with a hurricane.
An Asian perspective on the management of distal radius fractures.
Sebastin, Sandeep J; Chung, Kevin C
2012-05-01
There is limited data regarding the epidemiology, pathology, and management of distal radius fractures from centers in Asia. The advanced economies in Asia include Hong Kong, Japan, Korea, Singapore, and Taiwan, whereas the prominent emerging economies are China, India, Malaysia, Philippines, and Thailand. This article examines the available epidemiological data from Asia, compares the management of distal radius fractures in the advanced and emerging Asian economies and how they compare with the current management in the west. It concludes by offering solutions for improving outcomes of distal radius fractures in Asia.
Relationship between elastic moduli and pore radius in clay aggregates
Fabricius, Ida Lykke
2011-01-01
Available experimental data on elastic velocities of clay-air mixtures and clay-brine mixtures as a function of porosity are re-interpreted. Pore radius as calculated from porosity and specific surface measured by BET seems to be the factor controlling stiffness of these un-cemented sediments....... For each of the two pore fluids: air or brine smectitic clay and kaolinitic clay seem to have similar power law relationships between a given elastic modulus and pore radius. These results indicate that pore radius and thus permeability of shale in the depth interval of mechanical compaction may...
Fracture of the distal radius: epidemiology and premanagement radiographic characterization.
Porrino, Jack A; Maloney, Ezekiel; Scherer, Kurt; Mulcahy, Hyojeong; Ha, Alice S; Allan, Christopher
2014-09-01
Fractures of the distal radius are common and frequently encountered by the radiologist. We review the epidemiology, classification, as well as the concept of instability. Salient qualitative and quantitative features of the distal radius fracture identifiable on the routine radiography series are highlighted. We conclude with a synopsis of descriptors that are of greatest utility to the clinician for treatment planning and that should be addressed in the radiology report. A detailed understanding of the intricacies of the distal radius fracture is necessary for the radiologist to provide a clinically relevant description.
Radius of 9C from the Asymptotic Normalization Coefficient
LI Zhi-Hong; GUO Bing; LIU Wei-Ping; BAI Xi-Xiang; LIAN Gang; SU Jun; YAN Sheng-Quan; WANG Bao-Xiang; ZENG Sheng
2005-01-01
@@ The asymptotic normalization coefficient (ANC) of9 C = 8 B+p deduced from 8 Li(d, p)9 Li reaction is used to obtainthe root-mean-square (rms) radius of the loosely bound proton in the 9C ground state. We obtain 1/2 = 3.61 fmfor the valence proton, which is significantly larger than the matter radius of 9 C. The probability of the valence proton outside the matter radius of 9 C is greater than 60%. The present work supports the conclusion that 9 Chas a proton halo structure.
and minimum plastic zone radius (MPZR) for four point bend ...
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LEFM) approach. ... where the radius of plastic zone takes either a local or global minimum depending on the ..... facilities provided by the Research Centre, B V B College of Engineering & ... American institute of physics conference proceedings.
Split radius-form blocks for tube benders
Lange, D. R.; Seiple, C. W.
1970-01-01
Two-piece, radius-form block permits accurate forming and removing of parts with more than a 180 degree bend. Tube bender can shape flexible metal tubing in applications dealing with plumbing, heating, and pressure transmission lines.
The Potato Radius: a Lower Minimum Size for Dwarf Planets
Lineweaver, Charles H
2010-01-01
Gravitational and electronic forces produce a correlation between the mass and shape of objects in the universe. For example, at an average radius of ~ 200 km - 300 km, the icy moons and rocky asteroids of our Solar System transition from a rounded potato shape to a sphere. We derive this potato-to-sphere transition radius -- or "potato radius" -- from first principles. Using the empirical potato radii of asteroids and icy moons, we derive a constraint on the yield strength of these bodies during their formative years when their shapes were determined. Our proposed ~ 200 km potato radius for icy moons would substantially increase the number of trans-Neptunian objects classified as dwarf planets.
Experiments towards resolving the proton charge radius puzzle
Antognini, A; Amaro, F D; Amaro, P; Abdou-Ahmed, M; Biraben, F; Chen, T -L; Covita, D S; Dax, A J; Diepold, M; Fernandes, L M P; Franke, B; Galtier, S; Gouvea, A L; Götzfried, J; Graf, T; Hänsch, T W; Hildebrandt, M; Indelicato, P; Julien, L; Kirch, K; Knecht, A; Kottmann, F; Krauth, J J; Liu, Y -W; Machado, J; Monteiro, C M B; Mulhauser, F; Nez, F; Santos, J P; Santos, J M F dos; Szabo, C I; Taqqu, D; Veloso, J F C A; Voss, A; Weichelt, B; Pohl, R
2015-01-01
We review the status of the proton charge radius puzzle. Emphasis is given to the various experiments initiated to resolve the conflict between the muonic hydrogen results and the results from scattering and regular hydrogen spectroscopy.
Experiments towards resolving the proton charge radius puzzle
Antognini A.
2016-01-01
Full Text Available We review the status of the proton charge radius puzzle. Emphasis is given to the various experiments initiated to resolve the conflict between the muonic hydrogen results and the results from scattering and regular hydrogen spectroscopy.
Deuteron charge radius from spectroscopy data in atomic deuterium
Pohl, Randolf; Udem, Thomas; Antognini, Aldo; Beyer, Axel; Fleurbaey, Hélène; Grinin, Alexey; Hänsch, Theodor W; Julien, Lucile; Kottmann, Franz; Krauth, Julian J; Maisenbacher, Lothar; Matveev, Arthur; Biraben, François
2016-01-01
We give a pedagogical description of the method to extract the charge radii and Rydberg constant from laser spectroscopy in regular hydrogen (H) and deuterium (D) atoms, that is part of the CODATA least-squares adjustment of the fundamental physical constants. We give a deuteron charge radius from D spectroscopy alone of 2.1415(45) fm. This value is independent of the proton charge radius, and five times more accurate than the value found in the CODATA Adjustment 10.
A Sharp upper bound for the spectral radius of a nonnegative matrix and applications
You, Lihua; Shu, Yujie; Zhang, Xiao-Dong
2016-01-01
In this paper, we obtain a sharp upper bound for the spectral radius of a nonnegative matrix. This result is used to present upper bounds for the adjacency spectral radius, the Laplacian spectral radius, the signless Laplacian spectral radius, the distance spectral radius, the distance Laplacian spectral radius, the distance signless Laplacian spectral radius of a graph or a digraph. These results are new or generalize some known results.
Predicting the failure load of the distal radius.
Muller, Monique E; Webber, Colin E; Bouxsein, Mary L
2003-06-01
The distal radius is an important site for the early detection of patients at risk for fracture. Since measuring bone strength in vivo is not possible, we evaluated which bone assessment method of the forearm would best predict failure load of the distal radius and computed a factor of risk for wrist fracture (Phi wrist). Thirty-eight cadaveric forearm specimens were measured by five different techniques to assess bone density, bone mineral content, geometry and trabecular structure at the distal forearm. The bone assessment techniques included dual-energy X-ray absorptiometry (DXA) of the radius, peripheral quantitative computed tomography (pQCT) of the 4% and 20% distal sites of the radius, DXA of the phalanges, digital X-ray radiogrammetry of the forearm (DXR-BMD), and quantitative ultrasound of the radius. The failure load of each excised radius was determined by simulating a fall on an outstretched hand. The pQCT measurements of polar stress-strain index and cortical content explained the greatest portion of variance in failure load (r2=0.82-0.85). Bone mineral content measures were generally better predictors of failure load (r2=0.53-0.85) than the corresponding volumetric or areal bone mineral density values (r2=0.22-0.69) measured by either pQCT or DXA. Multiple regression analysis showed that the addition of a bone geometry measure improved the ability of a bone density measure alone to predict failure load. There was high variability in the ability of different techniques and different variables within a given technique to predict failure load. Estimates of the factor of risk for wrist fracture (Phi wrist) revealed that the women in this study would have been likely to fracture their distal radius upon falling from a standing height (Phi wrist= 1.04), whereas the men would have likely withstood the impact without fracturing their wrist (Phi wrist= 0.79).
Optimal network modification for spectral radius dependent phase transitions
Rosen, Yonatan; Kirsch, Lior; Louzoun, Yoram
2016-09-01
The dynamics of contact processes on networks is often determined by the spectral radius of the networks adjacency matrices. A decrease of the spectral radius can prevent the outbreak of an epidemic, or impact the synchronization among systems of coupled oscillators. The spectral radius is thus tightly linked to network dynamics and function. As such, finding the minimal change in network structure necessary to reach the intended spectral radius is important theoretically and practically. Given contemporary big data resources such as large scale communication or social networks, this problem should be solved with a low runtime complexity. We introduce a novel method for the minimal decrease in weights of edges required to reach a given spectral radius. The problem is formulated as a convex optimization problem, where a global optimum is guaranteed. The method can be easily adjusted to an efficient discrete removal of edges. We introduce a variant of the method which finds optimal decrease with a focus on weights of vertices. The proposed algorithm is exceptionally scalable, solving the problem for real networks of tens of millions of edges in a short time.
Accuracy of distal radius positioning using an anatomical plate.
Vroemen, Joy C; Dobbe, Johannes G G; Sierevelt, Inger N; Strackee, Simon D; Streekstra, Geert J
2013-04-01
Over the past decade, several anatomical plates have been introduced to improve the result of open reduction and internal fixation of the distal radius. Using 3-dimensional imaging techniques, the authors studied the accuracy and reproducibility of distal radius positioning using anatomical plates.Distal radius fractures and the correction of these fractures were simulated with plastic bone models of radii. The authors simulated a defect by removing an arbitrary wedge shape from the artificial radii. Two surgeons corrected these fractures by placing 2 anatomical plate types according to the plate manufacturers' instructions. The residual positioning errors of the distal segment in relation to the unaffected radii were determined using 3-dimensional imaging and were compared with naturally occurring bilateral radius differences in healthy individuals. In many cases, positioning does not agree with differences based on bilateral asymmetry in healthy patients.This study indicated the accuracy of anatomical plates. Positioning an anatomical plate may lead to considerable residual errors in individual patients. Volar distal radius plate shapes differ among plate manufacturers. Therefore, one plate may perform better than another in an individual.
The radius distribution of planets around cool stars
Morton, Timothy D. [Department of Astrophysical Sciences, 4 Ivy Lane, Peyton Hall, Princeton University, Princeton, NJ 08544 (United States); Swift, Jonathan, E-mail: tdm@astro.princeton.edu [Department of Astrophysics, California Institute of Technology, MC 249-17, Pasadena, CA 91125 (United States)
2014-08-10
We calculate an empirical, non-parametric estimate of the shape of the period-marginalized radius distribution of planets with periods less than 150 days using the small yet well-characterized sample of cool (T{sub eff} < 4000 K) dwarf stars in the Kepler catalog. In particular, we present and validate a new procedure, based on weighted kernel density estimation, to reconstruct the shape of the planet radius function down to radii smaller than the completeness limit of the survey at the longest periods. Under the assumption that the period distribution of planets does not change dramatically with planet radius, we show that the occurrence of planets around these stars continues to increase to below 1 R{sub ⊕}, and that there is no strong evidence for a turnover in the planet radius function. In fact, we demonstrate using many iterations of simulated data that a spurious turnover may be inferred from data even when the true distribution continues to rise toward smaller radii. Finally, the sharp rise in the radius distribution below ∼3 R{sub ⊕} implies that a large number of planets await discovery around cool dwarfs as the sensitivities of ground-based transit surveys increase.
Evidence for a large radius of the 11Be projectile
So, W. Y.; Choi, K. S.; Cheoun, Myung-Ki; Kim, K. S.
2016-05-01
We investigate ratios of the elastic scattering cross section to Rutherford cross section, PE, and angular distributions of breakup cross section by using an optical model which exploits various long-range dynamic polarization potentials as well as short-range nuclear bare potentials for the 11Be projectile. From these simultaneous analyses, we extract a large radius of a halo projectile from the experimental data for PE and the angular distribution of the breakup cross section of the 11Be + 64Zn and 11 + 120Sn systems. It results from the fact that a large radius for the long-range nuclear potential is more reasonable for properly explaining these data simultaneously. The extracted reduced interaction radius turns out to be r0=3.18 ˜3.61 fm for 11Be nucleus, which is larger than the conventional value of r0=1.1 ˜1.5 fm used in the standard radius form R =r0A1 /3 . Furthermore, the larger radius as well as the normalization constant N is shown to be important for understanding Coulomb dipole strength distribution.
Radius variation of optical fibers with angstrom accuracy.
Sumetsky, M; Dulashko, Y
2010-12-01
We have developed a robust method for the unprecedentedly accurate angstrom-scale detection of local variations of the fiber radius based on the idea suggested by Birks et al. [IEEE Photon. Technol. Lett. 12, 182 (2000)]. The method uses an optical microfiber (MF) translated at a small distance along the tested fiber and periodically touching it at measurement points. At these points, the MF transmission spectrum exhibits whispering-gallery-mode (WGM) resonances shifting with the tested fiber radius. A simple and comprehensive optimization scheme, which determines the radius variation without visual recognition of resonances and treats their shifts simultaneously, is developed. The optics of WGM propagation is discussed, and the condition for the validity of the developed method is established.
A Precise Estimate of the Radius of HD 149026b
Nutzman, Philip; Winn, Joshua N; Knutson, Heather A; Fortney, Jonathan J; Holman, Matthew J; Agol, Eric
2008-01-01
We present Spitzer 8 micron transit observations of the extrasolar planet system HD 149026. At this wavelength, transit light curves are weakly affected by stellar limb-darkening, allowing for a simpler and more accurate determination of planetary parameters. We measure a planet-star radius ratio of R_p/R_s = 0.05158 +/- 0.00077, and in combination with ground-based data and independent constraints on the stellar mass and radius, we derive an orbital inclination of i = 85.4 +0.9/-0.8 deg. and a planet radius of 0.755 +/- 0.040 Jupiter radii. These measurements further support models in which the planet is greatly enriched in heavy elements.
Effect of sample radius on stability of electromagnetic levitation melting
马伟增; 郑红星; 季诚昌; 李建国
2004-01-01
Based on the power dissipating model of spherical sample in free convection gas medium and the expression of input power, the model of temperature calculation for electromagnetic levitation melting sample was established. Considering the limitation of levitation force and levitation sample temperature,the principle of stability levitation zone computation was determined. A spherical sample (ThDy)Fe2 under the protection of argon gas was examined, and the effect of radius of levitation sample and perturbation on the stable levitation zone was investigated.The results show that longitudinal perturbation and transverse perturbation can shorten the length of stable levitation zone and the range of levitation sample radius. By increasing the sample radius and weakening the perturbation the electromagnetic levitation melting stability of sample can be improved.
Extraction of the proton charge radius from experiments
Kelkar, N G; Nowakowski, M
2016-01-01
Static properties of hadrons such as their radii and other moments of the electric and magnetic distributions can only be extracted using theoretical methods and not directly measured from experiments. As a result, discrepancies between the extracted values from different precision measurements can exist. The proton charge radius, $r_p$, which is either extracted from electron proton elastic scattering data or from hydrogen atom spectroscopy seems to be no exception. The value $r_p = 0.84087(39)$ fm extracted from muonic hydrogen spectroscopy is about 4% smaller than that obtained from electron proton scattering or standard hydrogen spectroscopy. The resolution of this so called proton radius puzzle has been attempted in many different ways over the past six years. The present article reviews these attempts with a focus on the methods of extracting the radius.
Rational functions with maximal radius of absolute monotonicity
Loczi, Lajos
2014-05-19
We study the radius of absolute monotonicity R of rational functions with numerator and denominator of degree s that approximate the exponential function to order p. Such functions arise in the application of implicit s-stage, order p Runge-Kutta methods for initial value problems and the radius of absolute monotonicity governs the numerical preservation of properties like positivity and maximum-norm contractivity. We construct a function with p=2 and R>2s, disproving a conjecture of van de Griend and Kraaijevanger. We determine the maximum attainable radius for functions in several one-parameter families of rational functions. Moreover, we prove earlier conjectured optimal radii in some families with 2 or 3 parameters via uniqueness arguments for systems of polynomial inequalities. Our results also prove the optimality of some strong stability preserving implicit and singly diagonally implicit Runge-Kutta methods. Whereas previous results in this area were primarily numerical, we give all constants as exact algebraic numbers.
The PRad experiment and the proton radius puzzle
Gasparian Ashot
2014-06-01
Full Text Available New results from the recent muonic hydrogen experiments seriously questioned our knowledge of the proton charge radius, rp. The new value, with its unprecedented less than sub-percent precision, is currently up to eight standard deviation smaller than the average value from all previous experiments, triggering the well-known “proton charge radius puzzle” in nuclear and atomic physics. The PRad collaboration is currently preparing a novel, magnetic-spectrometer-free ep scattering experiment in Hall B at JLab for a new independent rp measurement to address this growing “puzzle” in physics.
Thoughts on the so-called radius-capitellum axis
Schild, H.; Mueller, H.A.; Wagner, H.; Baetz, W.
1982-02-01
We have studied 438 patients radiologically in order to observe the so-called 'radius-capitellum axis'. In about a quarter of people with normal elbows the axis passes lateral to the middle portion of the capitellum, so that even when there is marked deviation, there is no certainty that the humero-radial joint is abnormal. Deviation of the axis can be caused by changes in the shape of the capitellum or of the radius, or by distension of the capsule of the elbow joint, or by various changes in muscular pull.
Dome-shaped osteotomy for distal radius fracture malunions.
Brunelli, Giorgio A
2003-06-01
After having hinted to the various component of the malformity caused by malunions of the distal radius fracture, the various possibilities of correcting this deformity are described. The difficulty to correct all the components of the deformity are considered. Then a Dome-shaped osteotomy of the distal radius is described that allows to correct all the deformities in all the directions as the gliding plane of the osteotomy is spherical. The ulnar plus and the DRUJ alterations are corrected by means of an added Sauvé-Kapandji procedure that guarantees against any painful movement of the DRUJ preserving effective prono-supination.
Social Support Contributes to Outcomes following Distal Radius Fractures
Caitlin J. Symonette
2013-01-01
Full Text Available Background. Distal radius fractures are the most common fracture of the upper extremity and cause variable disability. This study examined the role of social support in patient-reported pain and disability at one year following distal radius fracture. Methods. The Medical Outcomes Study Social Support Survey was administered to a prospective cohort of 291 subjects with distal radius fractures at their baseline visit. Pearson correlations and stepwise linear regression models (F-to-remove 0.10 were used to identify whether social support contributes to wrist fracture outcomes. The primary outcome of pain and disability at one year was measured using the Patient Rated Wrist Evaluation. Results. Most injuries were low energy (67.5% and were treated nonoperatively (71.9%. Pearson correlation analysis revealed that higher reported social support correlated with improved Patient Rated Wrist Evaluation scores at 1 year, r(n=181=-0.22, P<0.05. Of the subscales within the Social Support Survey, emotional/informational support explained a significant proportion of the variance in 1-year Patient Rated Wrist Evaluation scores, R2=4.7%, F (1, 181 = 9.98, P<0.05. Conclusion. Lower emotional/informational social support at the time of distal radius fracture contributes a small but significant percentage to patient-reported pain and disability outcomes.
Optimal Taylor-Couette flow: Radius ratio dependence
Monico, Rodolfo Ostilla; Jannink, Tim J G; van Gils, Dennis P M; Verzicco, Roberto; Grossmann, Siegfried; Sun, Chao; Lohse, Detlef
2013-01-01
Taylor-Couette flow with independently rotating inner (i) and outer (o) cylinders is explored numerically and experimentally to determine the effects of the radius ratio {\\eta} on the system response. Numerical simulations reach Reynolds numbers of up to Re_i=9.5 x 10^3 and Re_o=5x10^3, corresponding to Taylor numbers of up to Ta=10^8 for four different radius ratios {\\eta}=r_i/r_o between 0.5 and 0.909. The experiments, performed in the Twente Turbulent Taylor-Couette (T^3C) setup, reach Reynolds numbers of up to Re_i=2x10^6$ and Re_o=1.5x10^6, corresponding to Ta=5x10^{12} for {\\eta}=0.714-0.909. Effective scaling laws for the torque J^{\\omega}(Ta) are found, which for sufficiently large driving Ta are independent of the radius ratio {\\eta}. As previously reported for {\\eta}=0.714, optimum transport at a non-zero Rossby number Ro=r_i|{\\omega}_i-{\\omega}_o|/[2(r_o-r_i){\\omega}_o] is found in both experiments and numerics. Ro_opt is found to depend on the radius ratio and the driving of the system. At a drivi...
Radius ratio effects on natural heat transfer in concentric annulus
Alipour, M.; Hosseini, R.; Kolaei, Alireza Rezania
2013-01-01
This paper studies natural convection heat transfer in vertical and electrically heated annulus. The metallic cylinders mounted concentrically in a parallel tube. Measurements are carried out for four input electric powers and three radius ratios with an apparatus immersed in stagnant air...
Radius-mass scaling laws for celestial bodies
Muradian, R.; S. Carneiro; Marques, R.
1999-01-01
In this letter we establish a connection between two-exponent radius-mass power laws for cosmic objects and previously proposed two-exponent Regge-like spin-mass relations. A new, simplest method for establishing the coordinates of Chandrasekhar and Eddington points is proposed.
3D imaging in corrective osteotomy of the distal radius
Vroemen, Joy
2013-01-01
The research described in this thesis is on the development, design, implementation and testing of new techniques for corrective osteotomy of the distal radius. The goal of this thesis is threefold. At first, possible pitfalls of conventional corrective osteotomy surgery were determined and quantifi
Surgical versus conservative treatment of distal radius fractures in elderly.
Trevisan, C; Klumpp, R; Nava, V; Riccardi, D; Recalcati, W
2013-10-01
The distal radius fractures (DRFs) are the second most common fracture in the elderly population. Despite their frequency, the optimal treatment of these fractures remains controversial. Several dogmatic myths on DRFs management may adversely affect their outcome and despite a strong trend versus surgical options, systematic reviews suggest that conservative treatment remains the safest option for DRFs in most cases.
Human Fertility Increases with the Marital-radius
Labouriau, Rodrigo; Amorim, António
2008-01-01
We report a positive association between marital radius (distance between mates' birthplaces) and fertility detected in a large population. Spurious association due to socioeconomic factors is discarded by a conditional analysis involving income, education, and urbanicity. Strong evidence...... of consanguinity's deleterious effects affecting an entire human population is provided...
Nonlinear buckling analyses of a small-radius carbon nanotube
Liu, Ning, E-mail: liuxiao@ase.buaa.edu.cn; Li, Min; Jia, Jiao [School of Aeronautic Science and Engineering, Beihang University, Beijing 100091 (China); Wang, Yong-Gang [Department of Applied Mechanics, China Agricultural University, Beijing 100083 (China)
2014-04-21
Carbon nanotube (CNT) was first discovered by Sumio Iijima. It has aroused extensive attentions of scholars from all over the world. Over the past two decades, we have acquired a lot of methods to synthesize carbon nanotubes and learn their many incredible mechanical properties such as experimental methods, theoretical analyses, and computer simulations. However, the studies of experiments need lots of financial, material, and labor resources. The calculations will become difficult and time-consuming, and the calculations may be even beyond the realm of possibility when the scale of simulations is large, as for computer simulations. Therefore, it is necessary for us to explore a reasonable continuum model, which can be applied into nano-scale. This paper attempts to develop a mathematical model of a small-radius carbon nanotube based on continuum theory. An Isotropic circular cross-section, Timoshenko beam model is used as a simplified mechanical model for the small-radius carbon nanotube. Theoretical part is mainly based on modified couple stress theory to obtain the numerical solutions of buckling deformation. Meanwhile, the buckling behavior of the small radius carbon nanotube is simulated by Molecular Dynamics method. By comparing with the numerical results based on modified couple stress theory, the dependence of the small-radius carbon nanotube mechanical behaviors on its elasticity constants, small-size effect, geometric nonlinearity, and shear effect is further studied, and an estimation of the small-scale parameter of a CNT (5, 5) is obtained.
Individualist-Collectivist Culture and Trust Radius : A Multilevel Approach
van Hoorn, André
2015-01-01
We apply a multilevel approach to examine empirically the nexus between individualist and collectivist culture on the one hand and people’s radius of trust on the other. People’s trust level (i.e., the intensity with which people trust other people) has been extensively studied. Increasingly, howeve
Injectivity Radius and Cartan Polyhedron for Simply Connected Symmetric Spaces
Ling YANG
2007-01-01
The author explores the relationship between the cut locus of. an arbitrary simply connected and compact Riemannian symmetric space and the Cartan polyhedron of corresponding restricted root system, and computes the injectivity radius and diameter for every type of irreducible ones.
On the mass–radius relation of hot stellar systems
Gieles, M.; BAumgardt, H.; Heggie, D.C.; Lamers, J.T.W.H.
2010-01-01
Most globular clusters have half-mass radii of a few pc with no apparent correlation with their masses. This is different from elliptical galaxies, for which the Faber–Jackson relation suggests a strong positive correlation between mass and radius. Objects that are somewhat in between globular clust
The charge radius and anapole moment of a free fermion
Gongora-T, A.; Stuart, R.G. (European Organization for Nuclear Research, Geneva (Switzerland). Theory Div.)
1992-07-01
We derive an expression for the charge radius and anapole moment of a free fermion induced at one loop in the standard Glashow-Salam-Weinberg model of electroweak interactions. The result, despite earlier claims to the contrary, is demonstrably gauge-invariant and observable in principle. (orig.).
Nonlinear buckling analyses of a small-radius carbon nanotube
Liu, Ning; Wang, Yong-Gang; Li, Min; Jia, Jiao
2014-04-01
Carbon nanotube (CNT) was first discovered by Sumio Iijima. It has aroused extensive attentions of scholars from all over the world. Over the past two decades, we have acquired a lot of methods to synthesize carbon nanotubes and learn their many incredible mechanical properties such as experimental methods, theoretical analyses, and computer simulations. However, the studies of experiments need lots of financial, material, and labor resources. The calculations will become difficult and time-consuming, and the calculations may be even beyond the realm of possibility when the scale of simulations is large, as for computer simulations. Therefore, it is necessary for us to explore a reasonable continuum model, which can be applied into nano-scale. This paper attempts to develop a mathematical model of a small-radius carbon nanotube based on continuum theory. An Isotropic circular cross-section, Timoshenko beam model is used as a simplified mechanical model for the small-radius carbon nanotube. Theoretical part is mainly based on modified couple stress theory to obtain the numerical solutions of buckling deformation. Meanwhile, the buckling behavior of the small radius carbon nanotube is simulated by Molecular Dynamics method. By comparing with the numerical results based on modified couple stress theory, the dependence of the small-radius carbon nanotube mechanical behaviors on its elasticity constants, small-size effect, geometric nonlinearity, and shear effect is further studied, and an estimation of the small-scale parameter of a CNT (5, 5) is obtained.
VOL AR PLATING OF DISTAL RADIUS FRACTURE : A RETROSPECTIVE ANALYSIS
Victor
2015-06-01
Full Text Available BACKGROUND: Treatment of distal radius has undergone remarkable changes since the time of Abraham colles. Conservative treatment with cast application has given way to operative techniques for better o utcome in high demand young individuals. Volar plating fo r distal end radius fractures is an effective technique which allows early mobilisation with re storation of r adial inclination , radial length , articular congruity and palmar tilt. MATERIALS AND METHODS: T his study was performed in chettinad hospital and research institute between January 2013 and M arch 2014. 24 patients with closed isolated distal end radius fractures treated with open reduction and internal fixation with plates and screws by volar approach were followed up retrospectively for a minimum period of one year . There were 17 men and 7 women. Mean age was 44 years (Range, 22 - 75 years. The fractures were classified based on the AO system. There were 4 A2, 12 B3, 5 C1, 3 C2 fracture types. RESULTS : All the patients were evaluated with standard anteroposterior and lateral radiographs and CT scans in c ase of intraarticular fractures . In all patie nts plating of distal end radius done by volar approach. Patients were followed postoperatively for one y ear radiologically and clinically by modified clinical scoring system by Green and O Brien. Five patients had excellent results, thirteen patients had good results with twenty five percent restriction of wrist function . Five patients had fair results. One patient had postop wound infection which required implant removal and external fixator application . CONCLUSION: With proper patient selection a nd accurate surgical techniques , volar plating continues to be a useful method of treatment for distal end radius fractures with minimal complications and allowing early return of patients to normal activities.
Unstable Distal Radius Fractures Treated by Volar Locking Anatomical Plates
Jose, Anto; Deniese, Pascal Noel; Babu, Abey Thomas; Rengasamy, Kanagasabai; Najimudeen, Syed
2017-01-01
Introduction Fracture of the distal end of radius represents the most common fracture of the upper extremity accounting for 16-20% of all fractures. Plating is now emerging as the gold standard for management of distal radius fractures due to increased rate of complications such as malunion, subluxation/dislocation of distal radio-ulnar joint or late collapse of fracture. Procedures such as closed reduction and cast immobilization, ligamentotaxis with external fixator and percutaneous pin fixation are no longer acceptable. Aim The purpose of the study was to evaluate the functional and radiological outcome of unstable distal radius fractures treated with the volar locking plate. Materials and Methods We reviewed 53 patients from January 2011 to December 2015, treated for unstable distal radius fractures using a volar locking compression plate. Standard radiographic and clinical assessment after 12 months (range 12-16 months) were measured and final functional and radiological outcome were assessed using the Modified Mayo wrist scoring system and Sarmiento’s modification of Lindstorm criteria respectively. Results There were 42 males and 11 females with an average age of 39.12±31.78 years (18-71 years). At the end of 12 months, 36 patients had an excellent radiological outcome and 10 patients had good radiological outcome as per Sarmiento’s modification of Lindstorm criteria. Eleven patients had an excellent functional outcome and 26 patients had a good functional outcome as per modified Mayo wrist scoring system. There was one case of superficial wound infection which subsided with intravenous antibiotics. Conclusion The volar locking plate fixation helps in early mobilization of the wrist, restores anatomy, allows early return to function, prevents secondary loss of reduction and hence is an effective treatment for unstable fractures of the distal radius. PMID:28274009
Variable radius cartography - History and perspectives of a new discipline
Scalera, Giancarlo
2014-05-01
The map that Toscanelli sent to Columbus was an unconscious application of cartography at a smaller radius than the real. The first really conscious attempts to represent the geography of Earth on globes of radius less than the current one occurred after the formulation of the concept of expanding Earth through geological time. The American chemist and geologist Richard Owen (1810-1890) in his book Key to the geology of the globe (1857) described the principles of what he himself called Anatomical Geology, with the Earth growing as a biological organism. The book contained a global paleogeographic map of the Earth that would have had a radius of about 4000 kilometers. In 1928 J.A.H. Kerkhoff (under the pseudonym Aero-dilettant) published a series of paleogeographic globes on which the modern oceans disappeared. With the same artisan methods of transfer continental outlines from a sphere to a smaller one, in 1933 O.C. Hilgenberg represented three different geological epochs, and, later, for the first time mapped paleopoles with their site-pole segments of meridian. Even today the traditional method of Hilgenberg is followed by senior researchers (Klaus Vogel, 2003) and younger geologists (James Maxlow). In England Hugh Owen applied the methods of traditional cartography to the variable radius one. His Atlas of Continental Displacement was in the 70s and 80s, for this discipline, a real milestone. While in the field of constant radius paleogeography the adherents to plate tectonics created many computer codes of automatic mapping (Bullard et al., 1965; Smith & Hallam, 1970; Scotese et al., 1979; and many others), in the variable radius field few tried to reach the same task. In 1972 in United States a first very simple attempt (but was not further developed) came from a private, R.B. Perry, followed by the still not-computerized Atlas of Owen, and both them constituted inspiration for the construction of a FORTRAN variable radius mapping code at INGV, with which it
21 CFR 886.1430 - Ophthalmic contact lens radius measuring device.
2010-04-01
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ophthalmic contact lens radius measuring device... lens radius measuring device. (a) Identification. An ophthalmic contact lens radius measuring device is an AC-powered device that is a microscope and dial gauge intended to measure the radius of a...
Transfer matrices of dipoles with bending radius variation
无
2011-01-01
With the increasing demand of high brightness in light source, the uniform dipole can not meet the needs of low emittance, and thus the dipole with bending radius variation is introduced in this paper. The transfer matrix of a non-uniform dipole whose bending radius is linearly changed is chosen as an example and a very simple calculation formula of non-uniform dipole transfer matrices is given. The transfer matrices of some common profile non-uniform dipoles are also listed. The comparison of these transfer matrices and the matrices calculated with slices method verifies the numerical accuracy of this formula. This method can make the non-uniform beam dynamic problem simpler, very helpful for emittance research and lattice design with non-uniform dipoles.
Error analysis for a laser differential confocal radius measurement system.
Wang, Xu; Qiu, Lirong; Zhao, Weiqian; Xiao, Yang; Wang, Zhongyu
2015-02-10
In order to further improve the measurement accuracy of the laser differential confocal radius measurement system (DCRMS) developed previously, a DCRMS error compensation model is established for the error sources, including laser source offset, test sphere position adjustment offset, test sphere figure, and motion error, based on analyzing the influences of these errors on the measurement accuracy of radius of curvature. Theoretical analyses and experiments indicate that the expanded uncertainty of the DCRMS is reduced to U=0.13 μm+0.9 ppm·R (k=2) through the error compensation model. The error analysis and compensation model established in this study can provide the theoretical foundation for improving the measurement accuracy of the DCRMS.
Predicting jet radius in electrospinning by superpositioning exponential functions
Widartiningsih, P. M.; Iskandar, F.; Munir, M. M.; Viridi, S.
2016-08-01
This paper presents an analytical study of the correlation between viscosity and fiber diameter in electrospinning. Control over fiber diameter in electrospinning process was important since it will determine the performance of resulting nanofiber. Theoretically, fiber diameter was determined by surface tension, solution concentration, flow rate, and electric current. But experimentally it had been proven that significantly viscosity had an influence to fiber diameter. Jet radius equation in electrospinning process was divided into three areas: near the nozzle, far from the nozzle, and at jet terminal. There was no correlation between these equations. Superposition of exponential series model provides the equations combined into one, thus the entire of working parameters on electrospinning take a contribution to fiber diameter. This method yields the value of solution viscosity has a linear relation to jet radius. However, this method works only for low viscosity.
Network partition via a bound of the spectral radius
Mondragon, R J
2015-01-01
Based on the density of connections between the nodes of high degree, we introduce two bounds of the spectral radius. We use these bounds to split a network into two sets, one of these sets contains the high degree nodes, we refer to this set as the spectral--core. The degree of the nodes of the subnetwork formed by the spectral--core gives an approximation to the top entries of the leading eigenvector of the whole network. We also present some numerical examples showing the dependancy of the spectral--core with the assortativity coefficient, its evaluation in several real networks and how the properties of the spectral--core can be used to reduce the spectral radius.
Core Deuterium Fusion and Radius Inflation in Hot Jupiters
Jaikumar, Prashanth; Rachid Ouyed
2016-06-01
Several laboratory-based studies have shown that the Deuterium fusion cross-section is enhanced in a solid deuterated target as compared to a gas target, attributable to enhanced mobility of deuterons in a metal lattice. As an application, we propose that, for core temperatures and compositions characterizing hot Jupiters, screened Deuterium fusion can occur deep in the interior, and show that the amount of radius inflation from this effect can be important if there is sufficient rock-ice in the core. The mechanism of screened Deuterium fusion, operating in the above temperature range, is generally consistent with the trend in radius anomaly with planetary equilibrium temperature. We also explore the trend with planetary mass using a simple analytic model.
External Fixation of Unstable Distal Radius Fracture. A Case Report
Yaniel Truffin Rodríguez
2014-12-01
Full Text Available Unstable fracture of the distal radius is a common injury. If not properly treated, it can cause major disturbance in the radiocarpal joint and impaired hand function. A case of a 42-year-old patient of rural origin without a history of previous conditions treated at the Gustavo Aldereguía Lima Hospital in Cienfuegos is presented. He suffered a fall on the outstretched hand, which led to an unstable fracture of the left distal radius. Emergency surgery consisting of manual fracture reduction under general anesthesia and fixation with RALCA minifixator plus a percutaneously placed Kirschner wire was performed. Since this fracture is often inadequately treated, the presentation of this case can be helpful to many orthopedic surgeons.
Radius fracture from an electrical injury involving an electric guitar.
Pappano, Dante
2010-03-01
Electrical injury ranges widely from simple shock and mild burns to more extensive superficial injury, internal injury, and mortality. Bony fracture from electrically-induced tetanic muscle contraction is a rare but recognized injury. We report the case of a 14-year-old boy who suffered a minor burn and radius fracture related to an electrical injury involving his electric guitar. An interesting pattern is emerging from available case reports of similar injuries.
Biomechanical Stability of Four Fixation Constructs for Distal Radius Fractures
Capo, John T.; Kinchelow, Tosca; Brooks, Kenneth; Tan, Virak; Manigrasso, Michaele; Francisco, Kristin
2009-01-01
Implants available for distal radius fracture fixation include dorsal nonlocked plating (DNLP), volar locked plating (VLP), radial–ulnar dual-column locked plating (DCPs), and locked intramedullary fixation (IMN). This study examines the biomechanical properties of these four different fixation constructs. In 28 fresh-frozen radii, a wedge osteotomy was performed, creating an unstable fracture model and the four fixation constructs employed (DNLP, VLP, DCPs, and IMN). Dorsal bending loads wer...
Formation scenarios and mass-radius relation for neutron stars
Zdunik, J L
2011-01-01
Neutron star crust, formed via accretion of matter from a companion in a low-mass X-ray binary (LMXB), has an equation of state (EOS) stiffer than that of catalyzed matter. At a given neutron star mass, M, the radius of a star with an accreted crust is therefore larger, by DR(M), than for usually considered star built of catalyzed matter. Using a compressible liquid drop model of nuclei, we calculate, within the one-component plasma approximation, the EOSs corresponding to different nuclear compositions of ashes of X-ray bursts in LMXB. These EOSs are then applied for studying the effect of different formation scenarios on the neutron-star mass-radius relation. Assuming the SLy EOS for neutron star's liquid core, derived by Douchin & Haensel (2001), we find that at M=1.4 M_sun the star with accreted crust has a radius more than 100 m larger that for the crust of catalyzed matter. Using smallness of the crust mass compared to M, we derive a formula that relates DR(M) to the difference in the crust EOS. Thi...
Habitability of Exomoons at the Hill or Tidal Locking Radius
Hinkel, Natalie R
2013-01-01
Moons orbiting extrasolar planets are the next class of object to be observed and characterized for possible habitability. Like the host-planets to their host-star, exomoons have a limiting radius at which they may be gravitationally bound, or the Hill radius. In addition, they also have a distance at which they will become tidally locked and therefore in synchronous rotation with the planet. We have examined the flux phase profile of a simulated, hypothetical moon orbiting at a distant radius around the confirmed exoplanets mu Ara b, HD 28185 b, BD +14 4559 b, and HD 73534 b. The irradiated flux on a moon at it's furthest, stable distance from the planet achieves it's largest flux gradient, which places a limit on the flux ranges expected for subsequent (observed) moons closer in orbit to the planet. We have also analyzed the effect of planetary eccentricity on the flux on the moon, examining planets that traverse the habitable zone either fully or partially during their orbit. Looking solely at the stellar ...
Simulation for Proton Charge Radius (PRad) Experiment at Jefferson Lab
Ye, Li; PRad Collaboration Collaboration
2016-09-01
The ``Proton Charge Radius Puzzle'' refers to 7 σ discrepancy between the proton charge radius extracted from muonic hydrogen Lamb shift measurements and that from the atomic hydrogen Lamb shift and e-p elastic scattering measurements. In order to get a better understanding of this puzzle, the PRad experiment (E12-11-106) was proposed and recently performed with 1.1 and 2.2 GeV unpolarized electron beam in Hall B at Jefferson Lab. The experiment aims to extract the electric form factor and the charge radius of proton by simultaneously measuring the e - p elastic scattering cross section and the Møller cross section at very low Q2(2 × 10-4 10-1(GeV / c) 2) region, with sub-percent precision. A windowless hydrogen gas flow target was used to better control the background. A high-efficiency and high-resolution calorimeter (HyCal) and a pair of Gas Electron Multiplier (GEM) chambers were used in the experiment. This talk will focus on comparing the detailed simulation of PRad experiment and its background with preliminary spectra from the data. This work is supported in part by NSF MRI Award PHY-1229153, the U.S. Department of Energy under Contacts No. DE-FG02-07ER41528, Thomas Jefferson National Laboratory, Mississippi State University and PRad collaboration.
Is the proton radius puzzle evidence of extra dimensions?
Dahia, F.; Lemos, A.S. [Universidade Federal da Paraiba, Department of Physics, Joao Pessoa, PB (Brazil)
2016-08-15
The proton charge radius inferred from muonic hydrogen spectroscopy is not compatible with the previous value given by CODATA-2010, which, on its turn, essentially relies on measurements of the electron-proton interaction. The proton's new size was extracted from the 2S-2P Lamb shift in the muonic hydrogen, which showed an energy excess of 0.3 meV in comparison to the theoretical prediction, evaluated with the CODATA radius. Higher-dimensional gravity is a candidate to explain this discrepancy, since the muon-proton gravitational interaction is stronger than the electron-proton interaction and, in the context of braneworld models, the gravitational potential can be hugely amplified in short distances when compared to the Newtonian potential. Motivated by these ideas, we study a muonic hydrogen confined in a thick brane. We show that the muon-proton gravitational interaction modified by extra dimensions can provide the additional separation of 0.3 meV between the 2S and 2P states. In this scenario, the gravitational energy depends on the higher-dimensional Planck mass and indirectly on the brane thickness. Studying the behavior of the gravitational energy with respect to the brane thickness in a realistic range, we find constraints for the fundamental Planck mass that solve the proton radius puzzle and are consistent with previous experimental bounds. (orig.)
Characterizing SL2S galaxy groups using the Einstein radius
Verdugo, T.; Motta, V.; Foex, G.
2014-01-01
Aims. We aim to study the reliability of RA (the distance from the arcs to the center of the lens) as a measure of the Einstein radius in galaxy groups. In addition, we want to analyze the possibility of using RA as a proxy to characterize some properties of galaxy groups, such as luminosity (L......) and richness (N). Methods. We analyzed the Einstein radius, θE, in our sample of Strong Lensing Legacy Survey (SL2S) galaxy groups, and compared it with RA, using three different approaches: 1) the velocity dispersion obtained from weak lensing assuming a singular isothermal sphere profile (θE,I); 2) a strong.......7 ± 0.2)RA, θE,II = (0.4 ± 1.5) + (1.1 ± 0.4)RA, and θE,III = (0.4 ± 1.5) + (0.9 ± 0.3)RA for each method respectively. We found weak evidence of anti-correlation between RA and z, with Log RA = (0.58 ± 0.06) − (0.04 ± 0.1)z, suggesting a possible evolution of the Einstein radius with z, as reported...
The Radius Distribution of Small Planets Around Cool Stars
Morton, Timothy D
2013-01-01
We calculate an empirical, non-parametric estimate of the shape of the radius distribution of small planets with periods less than 90 days using the small yet well-characterized sample of cool T_eff <4000 K dwarf stars in the Kepler catalog. Using a new technique we call a modified kernel density estimator (MKDE) and carefully correcting for incompleteness, we show that planets with radii ~1.25 R_earth are the most common planets around these stars. An apparent overabundance of planets with radii 2-2.5 R_earth may be evidence for a population of planets with H/He atmospheres. Lastly, the sharp rise in the radius distribution from ~4 R_earth to 2 R_earth implies that a large number of planets await discovery around cool dwarfs as the sensitivities of ground-based surveys increase. The radius distribution will continue to be tested with future Kepler results, but the features reported herein are robust features of the current dataset and thus invite theoretical explanation in the context of planetary system ...
Conversion of radius of curvature to power (and vice versa)
Wickenhagen, Sven; Endo, Kazumasa; Fuchs, Ulrike; Youngworth, Richard N.; Kiontke, Sven R.
2015-09-01
Manufacturing optical components relies on good measurements and specifications. One of the most precise measurements routinely required is the form accuracy. In practice, form deviation from the ideal surface is effectively low frequency errors, where the form error most often accounts for no more than a few undulations across a surface. These types of errors are measured in a variety of ways including interferometry and tactile methods like profilometry, with the latter often being employed for aspheres and general surface shapes such as freeforms. This paper provides a basis for a correct description of power and radius of curvature tolerances, including best practices and calculating the power value with respect to the radius deviation (and vice versa) of the surface form. A consistent definition of the sagitta is presented, along with different cases in manufacturing that are of interest to fabricators and designers. The results make clear how the definitions and results should be documented, for all measurement setups. Relationships between power and radius of curvature are shown that allow specifying the preferred metric based on final accuracy and measurement method. Results shown include all necessary equations for conversion to give optical designers and manufacturers a consistent and robust basis for decision-making. The paper also gives guidance on preferred methods for different scenarios for surface types, accuracy required, and metrology methods employed.
Methane Planets and their Mass-Radius Relation
Helled, Ravit; Vos, Eran
2015-01-01
Knowledge of both the mass and radius of an exoplanet allows us to estimate its mean density, and therefore, its composition. Exoplanets seem to fill a very large parameter space in terms of mass and composition, and unlike the solar-system's planets, exoplanets also have intermediate masses (~5-50 M_Earth) with various densities. In this letter, we investigate the behavior of the Mass-Radius relation for methane (CH_4) planets and show that when methane planets are massive enough (M_planet > ~15 M_Earth) the methane can dissociate and lead to a differentiated planet with a carbon core, a methane envelope, and a hydrogen atmosphere. The contribution of a rocky core to the behavior of CH_4 planet is considered as well. We also develop interior models for several detected intermediate-mass planets that could, in principle, be methane/methane-rich planets. The example of methane planets emphasizes the complexity of the Mass-Radius relation and the challenge in inferring the planetary composition uniquely.
Measurement of Capillary Radius and Contact Angle within Porous Media.
Ravi, Saitej; Dharmarajan, Ramanathan; Moghaddam, Saeed
2015-12-01
The pore radius (i.e., capillary radius) and contact angle determine the capillary pressure generated in a porous medium. The most common method to determine these two parameters is through measurement of the capillary pressure generated by a reference liquid (i.e., a liquid with near-zero contact angle) and a test liquid. The rate of rise technique, commonly used to determine the capillary pressure, results in significant uncertainties. In this study, we utilize a recently developed technique for independently measuring the capillary pressure and permeability to determine the equivalent minimum capillary radii and contact angle of water within micropillar wick structures. In this method, the experimentally measured dryout threshold of a wick structure at different wicking lengths is fit to Darcy's law to extract the maximum capillary pressure generated by the test liquid. The equivalent minimum capillary radii of different wick geometries are determined by measuring the maximum capillary pressures generated using n-hexane as the working fluid. It is found that the equivalent minimum capillary radius is dependent on the diameter of pillars and the spacing between pillars. The equivalent capillary radii of micropillar wicks determined using the new method are found to be up to 7 times greater than the current geometry-based first-order estimates. The contact angle subtended by water at the walls of the micropillars is determined by measuring the capillary pressure generated by water within the arrays and the measured capillary radii for the different geometries. This mean contact angle of water is determined to be 54.7°.
Fractal analysis of bone architecture at distal radius.
Tomomitsu, Tatsushi; Mimura, Hiroaki; Murase, Kenya; Sone, Teruki; Fukunaga, Masao
2005-12-20
Bone strength depends on bone quality (architecture, turnover, damage accumulation, and mineralization) as well as bone mass. In this study, human bone architecture was analyzed using fractal image analysis, and the clinical relevance of this method was evaluated. The subjects were 12 healthy female controls and 16 female patients suspected of having osteoporosis (age range, 22-70 years; mean age, 49.1 years). High-resolution CT images of the distal radius were acquired and analyzed using a peripheral quantitative computed tomography (pQCT) system. On the same day, bone mineral densities of the lumbar spine (L-BMD), proximal femur (F-BMD), and distal radius (R-BMD) were measured by dual-energy X-ray absorptiometry (DXA). We examined the correlation between the fractal dimension and six bone mass indices. Subjects diagnosed with osteopenia or osteoporosis were divided into two groups (with and without vertebral fracture), and we compared measured values between these two groups. The fractal dimension correlated most closely with L-BMD (r=0.744). The coefficient of correlation between the fractal dimension and L-BMD was very similar to the coefficient of correlation between L-BMD and F-BMD (r=0.783) and the coefficient of correlation between L-BMD and R-BMD (r=0.742). The fractal dimension was the only measured value that differed significantly between both the osteopenic and the osteoporotic subjects with and without vertebral fracture. The present results suggest that the fractal dimension of the distal radius can be reliably used as a bone strength index that reflects bone architecture as well as bone mass.
HABITABILITY OF EXOMOONS AT THE HILL OR TIDAL LOCKING RADIUS
Hinkel, Natalie R.; Kane, Stephen R., E-mail: natalie.hinkel@gmail.com [NASA Exoplanet Science Institute, Caltech, MS 100-22, 770 South Wilson Avenue, Pasadena, CA 91125 (United States)
2013-09-01
Moons orbiting extrasolar planets are the next class of object to be observed and characterized for possible habitability. Like the host-planets to their host-star, exomoons have a limiting radius at which they may be gravitationally bound, or the Hill radius. In addition, they also have a distance at which they will become tidally locked and therefore in synchronous rotation with the planet. We have examined the flux phase profile of a simulated, hypothetical moon orbiting at a distant radius around the confirmed exoplanets {mu} Ara b, HD 28185 b, BD +14 4559 b, and HD 73534 b. The irradiated flux on a moon at its furthest, stable distance from the planet achieves its largest flux gradient, which places a limit on the flux ranges expected for subsequent (observed) moons closer in orbit to the planet. We have also analyzed the effect of planetary eccentricity on the flux on the moon, examining planets that traverse the habitable zone either fully or partially during their orbit. Looking solely at the stellar contributions, we find that moons around planets that are totally within the habitable zone experience thermal equilibrium temperatures above the runaway greenhouse limit, requiring a small heat redistribution efficiency. In contrast, exomoons orbiting planets that only spend a fraction of their time within the habitable zone require a heat redistribution efficiency near 100% in order to achieve temperatures suitable for habitability. This means that a planet does not need to spend its entire orbit within the habitable zone in order for the exomoon to be habitable. Because the applied systems comprise giant planets around bright stars, we believe that the transit detection method is most likely to yield an exomoon discovery.
A generalized spectral radius formula and Olsen's question
Loring, Terry; Shulman, Tatiana
2012-01-01
Let A be a C⁎C⁎-algebra and I be a closed ideal in A. For x∈Ax∈A, its image in A/IA/I is denoted by x˙, and its spectral radius is denoted by r(x)r(x). We prove that max{r(x),‖x˙‖}=inf‖(1+i)−1x(1+i)‖ (where the infimum is taken over all i∈Ii∈I such that 1+i1+i is invertible), which generalizes th...
Charge Radius Measurement of the Halo Nucleus $^{11}$Li
Kluge, H-J; Kuehl, T; Simon, H; Wang, Haiming; Zimmermann, C; Onishi, T; Tanihata, I; Wakasugi, M
2002-01-01
%IS385 %title\\\\ \\\\The root-mean-square charge radius of $^{11}$Li will be determined by measuring the isotope shift of a suitable atomic transition in a laser spectroscopic experiment. Comparing the charge radii of the lithium isotopes obtained by this nuclear-model-independent method with the relevant mass radii obtained before will help to answer the question whether the proton distribution in halo nuclei at the neutron drip-line is decoupled to the first order from their neutron distribution. The necessary experimental sensitivity requires the maximum possible rate of $^{11}$Li nuclei in a beam of low emittance which can only be provided by ISOLDE.
Guidelines for measuring solar radius with Baily beads analysis
SIGISMONDI Costantino
2009-01-01
By inspection of central eclipses videorecords, data of Baily beads timings are retrievable. Knowing the lunar limb profile at the moment of the eclipse we evaluate the excess or defect of solar limb when the Sun is assumed at its standard radius. Two procedures of data analysis are here presented: one based on limb heights and the other on times. While these methods are based upon Occult 4 software, they can be used with other ephemerides and new lunar profiles. The example of 2006 total eclipse data, with its remarkably negative value of ΔR=-0.41"±0.04", is presented.
Guidelines for measuring solar radius with Baily beads analysis
SIGISMONDI; Costantino
2009-01-01
By inspection of central eclipses videorecords, data of Baily beads timings are retrievable. Knowing the lunar limb profile at the moment of the eclipse we evaluate the excess or defect of solar limb when the Sun is assumed at its standard radius. Two procedures of data analysis are here presented: one based on limb heights and the other on times. While these methods are based upon Occult 4 software, they can be used with other ephemerides and new lunar profiles. The example of 2006 total eclipse data, with its remarkably negative value of ΔR= - 0.41"± 0.04", is presented.
Modelling Acoustic Wave Propagation in Axisymmetric Varying-Radius Waveguides
Bæk, David; Willatzen, Morten
2008-01-01
A computationally fast and accurate model (a set of coupled ordinary differential equations) for fluid sound-wave propagation in infinite axisymmetric waveguides of varying radius is proposed. The model accounts for fluid heat conduction and fluid irrotational viscosity. The model problem is solved...... by expanding solutions in terms of cross-sectional eigenfunctions following Stevenson’s method. A transfer matrix can be easily constructed from simple model responses of a given waveguide and later used in computing the response to any complex wave input. Energy losses due to heat conduction and viscous...
Finite Larmor radius influence on MHD solitary waves
E. Mjølhus
2009-04-01
Full Text Available MHD solitons are studied in a model where the usual Hall-MHD model is extended to include the finite Larmor radius (FLR corrections to the pressure tensor. The resulting 4-dimensional set of differential equations is treated numerically. In this extended model, the point at infinity can be of several types. Necessary for the existence of localized solutions is that it is either a saddle-saddle, a saddle-center, or, possibly, a focus-focus. In cases of saddle-center, numerical solutions for localized travelling structures have been obtained, and compared with corresponding results from the Hall-MHD model.
Experimental Method for Microbubbles Dynamics Monitoring and Radius Sizing
Fouan, Damien; Achaoui, Younes; Payan, Cedric; Mensah, Serge
Rationale and aim: Within the context of divers' decompression illness prevention, ultrasonic detection and sizing of circulating microbubbles in blood is of great interest. In order to be representative of the divers gas tension level (supersaturation) and thus, to optimize decompression stages, the measurements (made in the right ventricle region) should be performed during a short period of time (ventricle filling <20 ms), efficient to detect a broad range of bubbles' radii population (radius from 20 to 200 _m) and harmless (Mechanical Index MI<0.3).
Paediatric post-traumatic cortical defects of the distal radius
Roach, Richard T.; Summers, Bruce N. [Department of Orthopaedics, Princess Royal Hospital, Telford (United Kingdom); Cassar-Pullicino, Victor [Department of Radiology, Robert Jones and Agnes Hunt Hospital, Oswestry, Shropshire (United Kingdom)
2002-05-01
Paediatric post-traumatic cortical defects, although rare, are predominately seen affecting the distal radius following a greenstick or torus fracture. We review the literature and present a further two cases supported by CT and MRI. Images from an acute greenstick fracture are also presented to help understand the pathogenesis. Defects are typically solitary on plain radiographs and are usually noticed late, proximal to the site of compression. They are non-expansile in an otherwise healthy child. CT and MRI may reveal smaller multiple subperiosteal defects. Typical defects require no further management other than reassurance and advice that they may occasionally cause discomfort but resolve with time. (orig.)
Trajectory Calculator for Finite-Radius Cutter on a Lathe
Savchenkov, Anatoliy; Strekalov, Dmitry; Yu, Nan
2009-01-01
A computer program calculates the two-dimensional trajectory (radial vs. axial position) of a finite-radius-of-curvature cutting tool on a lathe so as to cut a workpiece to a piecewise-continuous, analytically defined surface of revolution. (In the original intended application, the tool is a diamond cutter, and the workpiece is made of a crystalline material and is to be formed into an optical resonator disk.) The program also calculates an optimum cutting speed as F/L, where F is a material-dependent empirical factor and L is the effective instantaneous length of the cutting edge.
Comments on “Reverberation Radius in Real Rooms”
P. Jafari Shalkouhi
2012-11-01
Full Text Available The goal of this letter is to comment on the article "Reverberation Radius in Real Rooms" by Mijić and Mašović (2010. Mijić and Mašović measured critical distance and reverberation time in four different size rooms from 125 Hz to 4 kHz octave bands. They proposed a method for measurement of critical distance. This paper confirms that the measurements of critical distance made by Mijić and Mašović were not accurate at some frequencies.
Post-traumatic cystic lesion following fracture of the radius
Papadimitriou, Nikolaos G.; Christophorides, John; Beslikas, Theodoros A.; Papadimitriou, Ageliki G. [Aristotle University of Thessaloniki, 2. Orthopaedic University Clinic, Thessaloniki (Greece); Doulianaki, Eleni G. [Aristotle University of Thessaloniki, 1. Pediatric University Clinic, Thessaloniki (Greece)
2005-07-01
Post-traumatic cystic lesions are an uncommon complication of fractures in children. They are benign, asymptomatic, non-expansive and tend to resolve spontaneously. Their cause seems to be the invasion of bone-marrow fat by subperiosteal hematoma, which may be visible on radiographs during fracture consolidation of the newly formed subperiosteal bone. The case we present is of cyst formation following a fracture of the distal radius and we evaluate the role of yellow bone marrow in the pathogenesis of the cyst. Its typical features clear differentiation from other lesions, preventing unnecessary and, possibly, invasive examinations. (orig.)
Two empirical regimes of the planetary mass-radius relation
Bashi, Dolev; Helled, Ravit; Zucker, Shay; Mordasini, Christoph
2017-08-01
Today, with the large number of detected exoplanets and improved measurements, we can reach the next step of planetary characterization. Classifying different populations of planets is not only important for our understanding of the demographics of various planetary types in the galaxy, but also for our understanding of planet formation. We explore the nature of two regimes in the planetary mass-radius (M-R) relation. We suggest that the transition between the two regimes of "small" and "large" planets occurs at a mass of 124 ± 7M⊕ and a radius of 12.1 ± 0.5R⊕. Furthermore, the M-R relation is R ∝ M0.55 ± 0.02 and R ∝ M0.01 ± 0.02 for small and large planets, respectively. We suggest that the location of the breakpoint is linked to the onset of electron degeneracy in hydrogen, and therefore to the planetary bulk composition. Specifically, it is the characteristic minimal mass of a planet that consists of mostly hydrogen and helium, and therefore its M-R relation is determined by the equation of state of these materials. We compare the M-R relation from observational data with the relation derived by population synthesis calculations and show that there is a good qualitative agreement between the two samples.
What is the largest Einstein radius in the universe?
Oguri, Masamune
2008-01-01
The Einstein radius plays a central role in lens studies as it characterises the strength of gravitational lensing. The distribution of Einstein radii near the upper cutoff should probe the largest mass concentrations in the universe. Adopting a triaxial halo model, we compute expected distributions of large Einstein radii. To assess the cosmic variance, we generate a number of all-sky Monte-Carlo realisations. We find that the expected largest Einstein radius in the universe is sensitive to the cosmological model: for a source redshift z=1, they are 42^{+9}_{-7}, 35^{+8}_{-6}, and 54^{+12}_{-7} arcseconds, assuming best-fit parameters of the WMAP5, WMAP3 and WMAP1 data, respectively. These values are broadly consistent with current observations given their incompleteness. For the same source redshift, we expect in all-sky 35 (WMAP5), 15 (WMAP3), and 150 (WMAP1) clusters that have Einstein radii larger than 20''. Whilst the values of the largest Einstein radii are almost unaffected by the primordial non-Gauss...
Some issues concerning the proton charge radius puzzle
Walcher, Thomas
2012-01-01
An explanation of the difference of the charge radius of the proton as determined from the Lamb shift in electronic hydrogen and from elastic electron scattering off the proton on the one side and the recent high precision determination with muonic hydrogen on the other side is presented. It is shown that the modification of the $2S_{1/2}$ and $2P_{3/2}$ wave functions by the "Uehling potential" yields a correction to the theoretical Lamb shift of $\\delta (\\Delta E_{\\textrm{Lamb}}) = 0.302$ meV which has to be compared to $\\delta (\\Delta E_{\\textrm{Lamb}}) = 0.322(46)$ meV equivalent to the stated radius difference. The explanation is based on the realization that the bound state wave functions modified by the external "Uehling potential" have to be propagated by the vacuum polarization propagator in order to give the correct leading order Lamb shift. It is argued that a conflicting relativistic calculation neglects this propagation aspect. The explanation demonstrates that the Lamb shift is dynamically induc...
Is the proton radius puzzle an evidence of extra dimensions?
Dahia, F
2015-01-01
The proton charge radius inferred from muonic hydrogen spectroscopy is not compatible with the previous value given by CODATA-2010, which, on its turn, essentially relies on measurements of the electron-proton interaction. The proton's new size was extracted from the 2S-2P Lamb shift in the muonic hydrogen, which showed an energy excess of 0.3 meV in comparison to the theoretical prediction, evaluated with the CODATA radius. Higher-dimensional gravity is a candidate to explain this discrepancy, since the muon-proton gravitational interaction is stronger than the electron-proton interaction and, in the context of braneworld models, the gravitational potential can be hugely amplified in short distances when compared to the Newtonian potential. Motivated by these ideas, we study a muonic hydrogen confined in a thick brane. We show that the muon-proton gravitational interaction modified by extra dimensions can provide the additional separation of 0.3 meV between 2S and 2P states. In this scenario, the gravitation...
Automated bone age assessment of older children using the radius
Tsao, Sinchai; Gertych, Arkadiusz; Zhang, Aifeng; Liu, Brent J.; Huang, Han K.
2008-03-01
The Digital Hand Atlas in Assessment of Skeletal Development is a large-scale Computer Aided Diagnosis (CAD) project for automating the process of grading Skeletal Development of children from 0-18 years of age. It includes a complete collection of 1,400 normal hand X-rays of children between the ages of 0-18 years of age. Bone Age Assessment is used as an index of skeletal development for detection of growth pathologies that can be related to endocrine, malnutrition and other disease types. Previous work at the Image Processing and Informatics Lab (IPILab) allowed the bone age CAD algorithm to accurately assess bone age of children from 1 to 16 (male) or 14 (female) years of age using the Phalanges as well as the Carpal Bones. At the older ages (16(male) or 14(female) -19 years of age) the Phalanges as well as the Carpal Bones are fully developed and do not provide well-defined features for accurate bone age assessment. Therefore integration of the Radius Bone as a region of interest (ROI) is greatly needed and will significantly improve the ability to accurately assess the bone age of older children. Preliminary studies show that an integrated Bone Age CAD that utilizes the Phalanges, Carpal Bones and Radius forms a robust method for automatic bone age assessment throughout the entire age range (1-19 years of age).
Measurement of the $\\Sigma^{-}$ Charge Radius at SELEX
Eschrich, I
1998-01-01
The charge radii of Sigma^- and pi^- have been determined by direct elastic scttering on shell electrons. The measurement was performed in the framework of the SELEX (E781) charm hadroproduction experiment at Fermilab which employs a 600 GeV/c high-intensity Sigma^-/pi^- beam and a 3-stage magnetic spectrometer covering 0.1 <= x_F <= 1.0. Scattering angles and momenta of both hadron and electron were measured with high precision using silicon microstrip detectors, thus allowing for a segmented solid target. Two TRDs provided full particle identification. A preliminary result for the Sigma^- charge radius for a four-momentum transfer squared of 0.03 GeV^2/c^2 <= Q^2 <= 0.16 GeV^2/c^2 will be reported. In a parallel analysis the pi^- charge radius has been determined for 0.03 GeV^2/c^2 <= Q^2 <= 0.2 GeV^2/c^2, and is found to be consistent with previous experiments.
Stellar Initial Mass Function: Trends With Galaxy Mass And Radius
Parikh, Taniya
2017-06-01
There is currently no consensus about the exact shape and, in particular, the universality of the stellar initial mass function (IMF). For massive galaxies, it has been found that near-infrared (NIR) absorption features, which are sensitive to the ratio of dwarf to giant stars, deviate from a Milky Way-like IMF; their modelling seems to require a larger fraction of low mass stars. There are now increasing results looking at whether the IMF varies not only with galaxy mass, but also radially within galaxies. The SDSS-IV/MaNGA integral-field survey will provide spatially resolved spectroscopy for 10,000 galaxies at R 2000 from 360-1000nm. Spectra of early-type galaxies were stacked to achieve high S/N which is particularly important for features in the NIR. Trends with galaxy radius and mass were compared to stellar population models for a range of absorption features in order to separate degeneracies due to changes in stellar population parameters, such as age, metallicity and element abundances, with potential changes in the IMF. Results for 611 galaxies show that we do not require an IMF steeper than Kroupa as a function of galaxy mass or radius based on the NaI index. The Wing-Ford band hints towards a steeper IMF at large radii however we do not have reliable measurements for the most massive galaxies.
Biomechanical stability of four fixation constructs for distal radius fractures.
Capo, John T; Kinchelow, Tosca; Brooks, Kenneth; Tan, Virak; Manigrasso, Michaele; Francisco, Kristin
2009-09-01
Implants available for distal radius fracture fixation include dorsal nonlocked plating (DNLP), volar locked plating (VLP), radial-ulnar dual-column locked plating (DCPs), and locked intramedullary fixation (IMN). This study examines the biomechanical properties of these four different fixation constructs. In 28 fresh-frozen radii, a wedge osteotomy was performed, creating an unstable fracture model and the four fixation constructs employed (DNLP, VLP, DCPs, and IMN). Dorsal bending loads were applied and bending stiffness, load to yield 5 mm displacement, and ultimate failure were measured. Bending stiffness for VLP (16.7 N/mm) was significantly higher than for DNLP (6.8 N/mm), while IMN (12.6 N/mm) and DCPs (11.8 N/mm) were similar. Ultimate load to failure occurred at 278.2 N for the VLP, 245.7 N for the IMN, and 52.0 N for the DNLP. The VLP was significantly stronger than the DNLP and DCPs, and the IMN and DCPs were stronger than the DNLP. The VLP has higher average bending stiffness, ultimate bending strength, and resistance to 5 mm displacement than the other constructs and significantly higher ultimate bending strength than the DCPs and DNLP. There was no statistically significant difference between the VLP and IMN. VLP and IMN fixation of distal radius fractures can achieve comparable stability.
Takagi, Hiroshi; Wu, Wenjie
2016-03-01
Even though the maximum wind radius (Rmax) is an important parameter in determining the intensity and size of tropical cyclones, it has been overlooked in previous storm surge studies. This study reviews the existing estimation methods for Rmax based on central pressure or maximum wind speed. These over- or underestimate Rmax because of substantial variations in the data, although an average radius can be estimated with moderate accuracy. As an alternative, we propose an Rmax estimation method based on the radius of the 50 kt wind (R50). Data obtained by a meteorological station network in the Japanese archipelago during the passage of strong typhoons, together with the JMA typhoon best track data for 1990-2013, enabled us to derive the following simple equation, Rmax = 0.23 R50. Application to a recent strong typhoon, the 2015 Typhoon Goni, confirms that the equation provides a good estimation of Rmax, particularly when the central pressure became considerably low. Although this new method substantially improves the estimation of Rmax compared to the existing models, estimation errors are unavoidable because of fundamental uncertainties regarding the typhoon's structure or insufficient number of available typhoon data. In fact, a numerical simulation for the 2013 Typhoon Haiyan as well as 2015 Typhoon Goni demonstrates a substantial difference in the storm surge height for different Rmax. Therefore, the variability of Rmax should be taken into account in storm surge simulations (e.g., Rmax = 0.15 R50-0.35 R50), independently of the model used, to minimize the risk of over- or underestimating storm surges. The proposed method is expected to increase the predictability of major storm surges and to contribute to disaster risk management, particularly in the western North Pacific, including countries such as Japan, China, Taiwan, the Philippines, and Vietnam.
On the inner radius of univalency by pre-Schwarzian derivative
2007-01-01
In this paper,the inner radius of univalency of hyperbolic domains by pre-Schwarzian derivative is studied,and some general formulas for the lower bound of the inner radius are established. As their applications,the lower bounds of inner radiuses for angular domains and strongly starlike domains are obtained.
STABILITY RADIUS OF NON-SMOOTH PRITCHARD-SALAMON SYSTEMS AND THE ALGEBRAIC RICCATI EQUATION
Weisheng JIANG; Falun HUANG; Tingyu ZHU
2009-01-01
The authors discuss the stability radius of the non-smooth Pritchard-Salamon systems under structured perturbations. A formula for the stability radius in terms of the norm of a certain input-output operator is obtained. Furthermore, the relationship between stability radius and the solvability of some type of algebraic Riccati equations is given.
On the inner radius of univalency by pre-Schwarzian derivative
Tao CHENG; Ji-xiu CHEN
2007-01-01
In this paper, the inner radius of univalency of hyperbolic domains by pre-Schwarzian derivative is studied, and some general formulas for the lower bound of the inner radius are established.As their applications, the lower bounds of inner radiuses for angular domains and strongly starlike domains are obtained.
Post-traumatic osteonecrosis of the lunate after fracture of the distal radius.
Nakanishi, Akito; Yajima, Hiroshi; Kisanuki, Osamu
2014-12-01
We present a case of post-traumatic osteonecrosis of the lunate after fracture of the distal radius. Post-traumatic osteonecrosis of the carpal lunate after a fracture of the distal radius has, to our knowledge, not been reported previously. We treated the patient with vascularised bone graft from the distal radius, with a satisfactory result.
Severely comminuted radius fracture presenting as a signature patterned injury
Saurabh Jain
2016-01-01
Full Text Available Dilemma still prevails, regarding the exact management of mangled extremity injuries between limb salvage versus amputation, each having there own set of complications. We here present a case of severely comminuted fractures of radius (bag of bones along with the multiple criss-cross shaped lacerated wounds on the forearm and wrist presenting as a “signature pattern injury” caused by entrapment of the limb in the concrete mixer. MESS score of patient was 8, a score valid for amputation, but contrary, we successfully salvaged the patient's limb with use of radio-carpal distracter. Management of mangled injuries should be individualized, with due consideration to the mechanism and force of injury, associated injuries, and the patient profile.
Severely comminuted radius fracture presenting as a signature patterned injury.
Jain, Saurabh; Rajan, Sunil; Srivastava, Abhishek
2016-01-01
Dilemma still prevails, regarding the exact management of mangled extremity injuries between limb salvage versus amputation, each having there own set of complications. We here present a case of severely comminuted fractures of radius (bag of bones) along with the multiple criss-cross shaped lacerated wounds on the forearm and wrist presenting as a "signature pattern injury" caused by entrapment of the limb in the concrete mixer. MESS score of patient was 8, a score valid for amputation, but contrary, we successfully salvaged the patient's limb with use of radio-carpal distracter. Management of mangled injuries should be individualized, with due consideration to the mechanism and force of injury, associated injuries, and the patient profile.
How to extract physics from HBT radius parameters
Heinz, Ulrich W
1996-01-01
I review recent progress in the understanding of the connection between the space-time structure of the particle emitting source and the form of the two-particle correlation function in momentum space. Based on a new scheme for calculating the HBT radius parameters from the emission function, strategies are suggested to separate for rapidly expanding sources the information on the spatial and temporal structure of the source. To this end a new fitting function for the two-particle correlation function is proposed. Its usefulness is demonstrated for a typical expanding model source, and it is shown how the dependence of the resulting fit parameters on the momentum of the particle pair can be used to measure the longitudinal and transverse expansion of the source.
Inductive voltage adder (IVA) for submillimeter radius electron beam
Mazarakis, M.G.; Poukey, J.W.; Maenchen, J.E. [and others
1996-12-31
The authors have already demonstrated the utility of inductive voltage adder accelerators for production of small-size electron beams. In this approach, the inductive voltage adder drives a magnetically immersed foilless diode to produce high-energy (10--20 MeV), high-brightness pencil electron beams. This concept was first demonstrated with the successful experiments which converted the linear induction accelerator RADLAC II into an IVA fitted with a small 1-cm radius cathode magnetically immersed foilless diode (RADLAC II/SMILE). They present here first validations of extending this idea to mm-scale electron beams using the SABRE and HERMES-III inductive voltage adders as test beds. The SABRE experiments are already completed and have produced 30-kA, 9-MeV electron beams with envelope diameter of 1.5-mm FWHM. The HERMES-III experiments are currently underway.
The neutrino charge radius is a physical observable
Bernabeu, J; Vidal, J
2004-01-01
We present a method which allows, at least in principle, the direct extraction of the gauge-invariant and process-independent neutrino charge radius (NCR) from experiments. Under special kinematic conditions, the judicious combination of neutrino and anti-neutrino forward differential cross-sections allows the exclusion of all target-dependent contributions, such as gauge-independent box-graphs, not related to the NCR. We show that the remaining contributions contain universal, renormalization group invariant combinations, such as the electroweak effective charge and the running mixing angle, which must be also separated out. By considering the appropriate number of independent experiments we show that one may systematically eliminate these universal terms, and finally express the NCR entirely in terms of physical cross-sections. Even though the kinematic conditions and the required precision may render the proposed experiments unfeasible, at the conceptual level the analysis presented here allows for the pro...
The muonic hydrogen Lamb shift and the proton radius
Peset, Clara
2014-01-01
We obtain a model independent expression for the muonic hydrogen Lamb shift up to $\\mathcal O (m_\\mu \\alpha^6, m_\\mu \\alpha^5 \\frac{m_\\mu^2}{m_\\rho^2})$. The hadronic effects are controlled by the chiral theory, which allows for their model independent determination. We give their complete expression including the pion and Delta particles. Out of this analysis and the experimental measurement of the muonic hydrogen Lamb shift we determine the electromagnetic proton radius: $r_p$=0.8412(15) fm. This number is at 6.8$\\sigma$ variance with respect to the CODATA value. The parametric control of the uncertainties allows us to obtain a model independent determination of the error, which is dominated by hadronic effects.
Constraints on the distribution of supernova remnants with Galactocentric radius
Green, D A
2015-01-01
Supernova remnants (SNRs) in the Galaxy are an important source of energy injection into the interstellar medium, and also of cosmic rays. Currently there are 294 known SNRs in the Galaxy, and their distribution with Galactocentric radius is of interest for various studies. Here I discuss some of the statistics of Galactic SNRs, including the observational selection effects that apply, and difficulties in obtaining distances for individual remnants from the `Sigma-D' relation. Comparison of the observed Galactic longitude distribution of a sample of bright Galactic SNRs -- which are not strongly affected by selection effects -- with those expected from models is used to constrain the Galactic distribution of SNRs. The best-fitting power-law/exponential model is more concentrated towards the Galactic centre than the widely used distribution obtained by Case & Bhattacharya (1998).
Decreasing "circumference" for increasing "radius" in axially symmetric gravitating systems
Lubo, M
2001-01-01
Apart from the flat space with an angular deficit, Einstein general relativity possesses another cylindrically symmetric solution. Because this configuration displays circles whose "circumferences" tend to zero when their "radius" go to infinity, it has not received much attention in the past. We propose a geometric interpretation of this feature and find that it implies field boundary conditions different from the ones found in the literature if one considers a source consisting of the scalar and the vector fields of a U(1) system . To obtain a non increasing energy density the gauge symmetry must be unbroken . For the Higgs potential this is achieved only with a vanishing vacuum expectation value but then the solution has a null scalar field. A non trivial scalar behaviour is exhibited for a potential of sixth order. The trajectories of test particles in this geometry are studied, its causal structure discussed. We find that this bosonic background can support a normalizable fermionic condensate but not suc...
Large-radius bipolaron and the polaron-polaron interaction
Kashirina, N I [Institute of Semiconductor Physics, National Academy of Sciences of Ukraine, Kiev (Ukraine); Lakhno, Viktor D [Institute of Mathematical Problems of Biology, Russian Academy of Sciences, Pushchino, Moscow region (Russian Federation)
2010-08-09
Research on the polaron-polaron interaction and the theory of large-radius bipolarons are reviewed. The difference between the two-center and one-center continuum bipolaron models in isotropic and anisotropic crystals is discussed. It is shown that the inclusion of electron-electron correlations can significantly reduce the bipolaron and D{sup -}-center energies as well as the energies of exchange-bound pairs of shallow hydrogen-like centers. The two-center bipolaron configuration corresponds to a shallow secondary minimum and is unstable. The phonon-mediated exchange interaction between Pekar polarons has an antiferromagnetic nature and exceeds the ferromagnetic interaction due to the Coulomb interaction of electrons localized in polaron potential wells. The possibility that the superfluidity of bipolarons can give rise to high-temperature superconductivity is discussed and problems related to the Wigner crystallization of a polaron gas are examined. (reviews of topical problems)
Sensor Activation and Radius Adaptation (SARA) in Heterogeneous Sensor Networks
Bartolini, Novella; la Porta, Thomas; Petrioli, Chiara; Silvestri, Simone
2010-01-01
In this paper we address the problem of prolonging the lifetime of wireless sensor networks (WSNs) deployed to monitor an area of interest. In this scenario, a helpful approach is to reduce coverage redundancy and therefore the energy expenditure due to coverage. We introduce the first algorithm which reduces coverage redundancy by means of Sensor Activation and sensing Radius Adaptation (SARA)in a general applicative scenario with two classes of devices: sensors that can adapt their sensing range (adjustable sensors) and sensors that cannot (fixed sensors). In particular, SARA activates only a subset of all the available sensors and reduces the sensing range of the adjustable sensors that have been activated. In doing so, SARA also takes possible heterogeneous coverage capabilities of sensors belonging to the same class into account. It specifically addresses device heterogeneity by modeling the coverage problem in the Laguerre geometry through Voronoi-Laguerre diagrams. SARA executes quickly and is guarante...
Massive radius-dependent flow slippage in carbon nanotubes
Siria, Alessandro; Secchi, Eleonora; Marbach, Sophie; Niguès, Antoine; Stein, Derek; Bocquet, Lydéric
2016-11-01
Nanofluidics is the frontier where the continuum picture of fluid mechanics confronts the atomic nature of matter. Recent reports indicate that carbon nanotubes exhibit exceptional water transport properties due to nearly frictionless interfaces and this has stimulated interest in nanotube-based membranes for desalination, nano-filtration, and energy harvesting. However, the fundamental mechanisms of water transport inside nanotubes and at water-carbon interfaces remain controversial, as existing theories fail to provide a satisfying explanation for the limited experimental results. We report a study of water jets emerging from single nanotubes made of carbon and boron-nitride materials. Our experiments reveal extensive and radius-dependent surface slippage in carbon nanotubes (CNT). In stark contrast, boron-nitride nanotubes (BNNT), which are crystallographically similar to CNTs but electronically different, exhibit no slippage. This shows that slippage originates in subtle atomic-scale details of the solid-liquid interface. ERC StG - NanoSOFT.
Heliocentric radius of the cosmic ray modulation boundary
Randall, B. A.; Van Allen, J. A.
1986-01-01
A semiempirical analysis is made of an extensive body of observed cosmic ray intensity data from Pioneers 10 and 11, and related spectral information from other authors, in order to infer the radius R of the modulation region surrounding the sun. During the period 1972-1985, the inferred values of R vary with time systematically and in a manner generally similar to that of sunspot numbers. The range of values of R is from 42 AU at the time of minimum solar activity (circa 1976) to 88 AU about 1.5 yr following the time of maximum solar activity (circa 1980). A specific, testable prediction is that Pioneer 10 will reach the modulation boundary in 1988, and will remain in its vicinity for several years thereafter.
Proton Radius, Darwin-Foldy Term and Radiative Corrections
Jentschura, U D
2010-01-01
We discuss the role of the so-called Darwin-Foldy term in the evaluation of the proton and deuteron charge radii from atomic hydrogen spectroscopy and nuclear scattering data. The question of whether this term should be included or excluded from the nuclear radius has been controversially discussed in the literature. We attempt to clarify which literature values correspond to which conventions. A detailed discussion of the conventions appears useful because a recent experiment [R. Pohl et al., Nature vol. 466, p. 213 (2010)] has indicated that there is a discrepancy between the proton charge radii inferred from ordinary ("electronic") atomic hydrogen and muonic hydrogen. We also investigate the role of quantum electrodynamic radiative corrections in the determination of nuclear radii from scattering data, and propose a definition of the nuclear self energy which is compatible with the subtraction of the radiative corrections in scattering experiments.
Measurement of the Σ- Charge Radius in the Selex Experiment
Simon, J.
2000-01-01
The charge radius of the Σ- has been determined by direct elastic scattering on shell electrons. The measurement was performed in the framework of the Selex (E781) charm hadroproduction experiment at Fermilab. Selex employs 600 GeV/c high-intensity Σ-/π- and p/π+ beams and a three-stage magnetic spectrometer covering 0.1 <= xF <= 1.0. The scattering angles and momenta of the hadron and the electron were measured with high precision using silicon microstrip detectors. Particle identification was provided by two TRDs. For control of systematic effects the charge radii of the proton and the π- were measured with the same apparatus and are found to be consistent with previous experiments.
Galaxy Mass, Metallicity, Radius and Star Formation Rates
Brisbin, Drew
2011-01-01
Working with 108,786 Sloan Digital Sky Survey low redshift galaxies, we have examined the relation between galaxy mass, metallicity, radius, and star formation rates. We subdivided the redshift range covered in our sample 0.072.8E10 Msun and exhibit high metallicities at high star formation rates, suggesting that for these galaxies star formation independent of mass infall plays a significant role. A toy model for the physics of infall accounts for the SFR Mi^(3/2) relation and permits us to estimate the mean densities and velocities of clumps of baryonic matter traversing the dark matter halos in which the SDSS galaxies may be embedded. The model also reproduces the gross features of the galaxy main sequence.
Relations between photoionization cross sections and photon radius
Liu, Shan-Liang
2016-01-01
The relations between photoionization cross sections and photon radius are obtained on basis of quantum mechanics and the particle-like properties of a photon. The photoionization cross sections of H atom and H-like ions, He atom and He like ions, alkali metal atoms, and Rydberg atoms are calculated using the relations. The calculation results are found to be good agreement with the known experimental data. The results show that the photoionization cross section is always smaller than the cross section of the photon to ionize the atom or ion and can be expressed as the product of the cross section of the photon and the probability that electron meets with the photon. These provide the intuitive understanding for the photoionization phenomena and open a new avenue of research on interaction between a photon and an atom or ion.
Nuclear charge radius measurements of radioactive beryllium isotopes
2002-01-01
We propose to measure the nuclear charge radii of the beryllium isotopes $^{7,9,10}$Be and the one-neutron halo isotope $^{11}$Be using laser spectroscopy of trapped ions. Ions produced at ISOLDE and ionized with the laser ion source will be cooled and bunched in the radio-frequency buncher of the ISOLTRAP experiment and then transferred into a specially designed Paul trap. Here, they will be cooled to temperatures in the mK range employing sympathetic and direct laser cooling. Precision laser spectroscopy of the isotope shift on the cooled ensemble in combination with accurate atomic structure calculations will provide nuclear charge radii with a precision of better than 3%. This will be the first model-independent determination of a one-neutron halo nuclear charge radius.
[Manifestation of Dupuytren nodules following fracture of the distal radius].
Wichelhaus, Alice; Wendt, M; Mielsch, N; Gradl, G; Mittlmeier, T
2015-02-01
The aim of this study is to evaluate the incidence of post-traumatic development of Dupuytren nodules in distal radius fractures treated operatively. In 2 prospective randomised studies for operative treatment of distal radius fractures, the formation of Dupuytren nodules was registered. One of the exclusion criteria was a pre-existing Dupuytren's disease at the date of trauma. In addition to the notification of the development of Dupuytren nodules, signs of a complex regional pain syndrome were registered as well as the wrist function, level of pain and grip strength. The Castaing and the Gartland and Werley scores were assessed. The clinical outcomes of patients with and without Dupuytren nodules were compared. 239 of 275 (87%) of the patients could be examined 1 year after the operation, consisting of 32 men and 207 women with a median age of 64.2 years. The patients with Dupuytren nodules were re-evaluated after 16-60 months (median 41.8) for progression of the disease. 21 patients (8.7%) developed changes of the palmar aponeurosis. In 20 patients nodules were stated, one patient showed a cord at the fourth ray of the injured hand. 19 out of 21 patients were female (90.5%). At re-evaluation after 41.8 months (16-60) progression could not be noted nor could similar changes be seen on the contralateral side. Patients with Dupuytren nodules were not handicapped in their hand function. 3 patients (14.3%) revealed a positive family history for Dupuytren's disease. Abuse of alcohol or diabetes was not present in any of the patients with Dupuytren nodules, 7 (33%) were smokers. The occurrence of Dupyutren nodules can be triggered by a trauma or operation. It may be speculated that these nodules are an entity of their own as no progression of the contracture could be seen during the follow-up period. © Georg Thieme Verlag KG Stuttgart · New York.
Thuysbaert, Gilles; Ringburg, Akkie; Petronilia, Steven; Vanden Berghe, Alex; Hollevoet, Nadine
2015-06-01
Ulnar variance and radial inclination are radiological parameters frequently used to evaluate displacement of distal radius fractures. In most studies measurements are based on the long central axis of the distal radius, although the axis of the distal ulna can also be used. The purpose of this study was to determine which axis is more reliable. Four observers performed measurements on standard anteroposterior digital wrist X-rays of 20 patients taken 1 and 2 months after sustaining an extra-articular distal radius fracture. Intraobserver reliability was similar with both methods. No difference was found in interobserver reliability between both methods for ulnar variance, but for radial inclination it was better with the axis through the radius. Measurements on two X-rays of the same wrist taken at a different moment were similar with both methods. It can be concluded that the central axis of the distal radius can remain the basis to determine ulnar variance and radial inclination.
Radius of lunar core estimated by GRAIL results
Matsumoto, K.; Yamada, R.; Kikuchi, F.; Iwata, T.; Hanada, H.; Ishihara, Y.; Kamata, S.; Sasaki, S.
2013-12-01
Internal structure and composition of the Moon provide important clue and constraints on theories for how the Moon formed and evolved. The Apollo seismic network has contributed to the internal structure modeling. Efforts have been made to detect the lunar core from the noisy Apollo data (e.g., [1], [2]), but there is scant information about the structure below the deepest moonquakes at about 1000 km depth. On the other hand, there have been geodetic studies to infer the deep structure of the Moon. For example, LLR (Lunar Laser Ranging) data analyses detected a displacement of the lunar pole of rotation, indicating that dissipation is acting on the rotation arising from a fluid core [3]. Bayesian inversion using geodetic data (such as mass, moments of inertia, tidal Love numbers k2 and h2, and quality factor Q) also suggests a fluid core and partial melt in the lower mantle region [4]. Recent analyses of GRAIL data have achieved the improved k2 accuracy; JPL solution is 0.02405 × 0.00018 [5], and GSFC solution is 0.02427 × 0.00026 [6]. The two solutions are consistent with each other within their error bounds, and the accuracy of k2 is now about 1 %. Such an accurately-determined Love number will contribute to constrain the structure of the lunar deep interior, such as the radius of the possible liquid core. We used geodetic data of the mass, the mean moment of inertia, the Love numbers h2 and k2 to infer the size of liquid core. It is difficult to tightly constrain the internal structure from the geodetic data only because there are trade-offs among the structures of crust, mantle, and core. In our preliminary analysis we used a 5-layer model and the mantle structure was constrained by VPREMOON [2] with 5 % error for density and 10 % error for shear and bulk moduli being assumed. An inversion using Markov chain Monte Carlo method indicates that the core radius is 480 × 50 km, but the density values were sampled around the assumed lower limit of 3600 kg/m3. When
What Is the Largest Einstein Radius in the Universe?
Oguri, Masamune; Blandford, Roger D.
2008-08-05
The Einstein radius plays a central role in lens studies as it characterizes the strength of gravitational lensing. In particular, the distribution of Einstein radii near the upper cutoff should probe the probability distribution of the largest mass concentrations in the universe. Adopting a triaxial halo model, we compute expected distributions of large Einstein radii. To assess the cosmic variance, we generate a number of Monte-Carlo realizations of all-sky catalogues of massive clusters. We find that the expected largest Einstein radius in the universe is sensitive to parameters characterizing the cosmological model, especially {sigma}{sub s}: for a source redshift of unity, they are 42{sub -7}{sup +9}, 35{sub -6}{sup +8}, and 54{sub -7}{sup +12} arcseconds (errors denote 1{sigma} cosmic variance), assuming best-fit cosmological parameters of the Wilkinson Microwave Anisotropy Probe five-year (WMAP5), three-year (WMAP3) and one-year (WMAP1) data, respectively. These values are broadly consistent with current observations given their incompleteness. The mass of the largest lens cluster can be as small as {approx} 10{sup 15} M{sub {circle_dot}}. For the same source redshift, we expect in all-sky {approx} 35 (WMAP5), {approx} 15 (WMAP3), and {approx} 150 (WMAP1) clusters that have Einstein radii larger than 2000. For a larger source redshift of 7, the largest Einstein radii grow approximately twice as large. While the values of the largest Einstein radii are almost unaffected by the level of the primordial non-Gaussianity currently of interest, the measurement of the abundance of moderately large lens clusters should probe non-Gaussianity competitively with cosmic microwave background experiments, but only if other cosmological parameters are well-measured. These semi-analytic predictions are based on a rather simple representation of clusters, and hence calibrating them with N-body simulations will help to improve the accuracy. We also find that these &apos
Failure of dual radius hydroxyapatite-coated acetabular cups
Zatti Giovanni
2008-08-01
Full Text Available Abstract Introduction Many kind of hydroxyapatite-coated cups were used, with favorable results in short term studies; it was supposed that its use could improve osteointegration of the cup, enhancing thus stability and survivorship. The purpose of this study is to analyze the long term behavior of the hemispheric HA coated, Dual Radius Osteonics cup and to discuss the way of failure through the exam of the revised components and of both periacetabular and osteolysis tissue. Materials and Methods Between 1994 and 1997, at the Department of Orthopedic Sciences of the Insubria University, using the posterolateral approach, were implanted 276 Dual Radius Osteonics® in 256 patients, with mean age of 63 years. Results At a mean follow-up of 10 years (range 8–12 years, 183 cups in 165 patients, were available for clinical and radiographical evaluation. 22 Cups among the 183 were revised (11%. The cause of revision was aseptic loosening in 17 cases, septic loosening in one case, periprosthetic fracture in another case, osteolysis and polyethylene wear in two cases and, finally, recurrent dislocations in the last one. In the remaining patients, mean HHS increased from a preoperative value of 50,15 to a postoperative value of 92,69. The mean polyethylene wear was 1,25 mm (min. 0,08, max. 3,9 mm, with a mean annual wear of 0,17 mm. The mean acetabular migration on the two axis was 1,6 mm and 1,8 mm. Peri-acetabular osteolysis were recorded in 89% of the implants (163 cases. The cumulative survivorship (revision as endpoint at the time was 88,9%. Conclusion Our study confirms the bad behavior of this type of cup probably related to the design, to the method of HA fixation. The observations carried out on the revised cup confirm these hypotheses but did not clarify if the third body wear could be a further problem. Another interesting aspect is the high incidence of osteolysis, which are often asymptomatic becoming a problem for the surgeon as the
[Py-Desmanet pinning in distal radius fractures].
Alexa, O; Popia, I
2009-01-01
Internal fixation by pinning is one of the most used methods of surgical treatment in fractures of the distal extremity of the radius. As in stable fractures a styloid pinning is satisfactory, in unstable fractures however we must resort to different patterns of pin insertion, in order to effectively prevent the secondary displacement of the fractured fragments. The elastic pinning described by Py and Desmanet is one of the possibilities of inserting the pins. The principle of this method is to use the bending-induced tension in the pins to counteract the postero-lateral displacing forces. The authors have treated by this technique five patients with distal radius fractures (3 women and 2 men) about 56 years of average age, all with good-quality bone, all with Colles' fracture pattern (2-4 cm above the radio-carpal articulation, no articular involvement, posterior displacement of the distal fragment). The reduction of the fractures was achieved by closed manipulation and controlled intraoperatively with the C-arm. We preferred to reduce the fractures before inserting the pins, although this is not compulsory, according to the authors of the technique. The approach was minimally-invasive, through two 1-cm long incisions. The pins, previously blunted and curved along the last centimeters, were introduced using a "T"-shaped handle. The potential complications, consisting of injuries of the many elements which cross the region, were avoided by sufficiently long incisions and identification and retraction of these elements (tendons, nervous branches) in order not to penetrate them with the pins. The aftertreatment consisted of immediate mobilization of the wrist in one patient, 21-day splinting in other two and 30-day splinting in the last two, depending on the intraoperative assessment of the stability of the fixation. The pins were removed at 45 days postoperatively in all cases. There were no complications such as loss of reduction or pin migration. In all cases
Failure of dual radius hydroxyapatite-coated acetabular cups.
D'Angelo, Fabio; Molina, Mauro; Riva, Giacomo; Zatti, Giovanni; Cherubino, Paolo
2008-08-07
Many kind of hydroxyapatite-coated cups were used, with favorable results in short term studies; it was supposed that its use could improve osteointegration of the cup, enhancing thus stability and survivorship. The purpose of this study is to analyze the long term behavior of the hemispheric HA coated, Dual Radius Osteonics cup and to discuss the way of failure through the exam of the revised components and of both periacetabular and osteolysis tissue. Between 1994 and 1997, at the Department of Orthopedic Sciences of the Insubria University, using the posterolateral approach, were implanted 276 Dual Radius Osteonics in 256 patients, with mean age of 63 years. At a mean follow-up of 10 years (range 8-12 years), 183 cups in 165 patients, were available for clinical and radiographical evaluation. 22 Cups among the 183 were revised (11%). The cause of revision was aseptic loosening in 17 cases, septic loosening in one case, periprosthetic fracture in another case, osteolysis and polyethylene wear in two cases and, finally, recurrent dislocations in the last one. In the remaining patients, mean HHS increased from a preoperative value of 50.15 to a postoperative value of 92.69. The mean polyethylene wear was 1.25 mm (min. 0.08, max 3.9 mm), with a mean annual wear of 0.17 mm. The mean acetabular migration on the two axis was 1.6 mm and 1.8 mm. Peri-acetabular osteolysis were recorded in 89% of the implants (163 cases). The cumulative survivorship (revision as endpoint) at the time was 88,9%. Our study confirms the bad behavior of this type of cup probably related to the design, to the method of HA fixation. The observations carried out on the revised cup confirm these hypotheses but did not clarify if the third body wear could be a further problem. Another interesting aspect is the high incidence of osteolysis, which are often asymptomatic becoming a problem for the surgeon as the patient refuses the possibility of a revision.
Nakashima, Kenichi; Stoller, Roger E; Xu, Haixuan
2015-08-26
The recombination radius of a Frenkel pair is a fundamental parameter for the object kinetic Monte Carlo (OKMC) and mean field rate theory (RT) methods that are used to investigate irradiation damage accumulation in irradiated materials. The recombination radius in bcc Fe has been studied both experimentally and numerically, however there is no general consensus about its value. The detailed atomistic processes of recombination also remain uncertain. Values from 1.0a0 to 3.3a0 have been employed as a recombination radius in previous studies using OKMC and RT. The recombination process of a Frenkel pair is investigated at the atomic level using the self-evolved atomistic kinetic Monte Carlo (SEAKMC) method in this paper. SEAKMC calculations reveal that a self-interstitial atom recombines with a vacancy in a spontaneous reaction from several nearby sites following characteristic pathways. The recombination radius of a Frenkel pair is estimated to be 2.26a0 by taking the average of the recombination distances from 80 simulation cases. In addition, we apply these procedures to the capture radius of a self-interstitial atom by a vacancy cluster. The capture radius is found to gradually increase with the size of the vacancy cluster. The fitting curve for the capture radius is obtained as a function of the number of vacancies in the cluster.
Possible Solutions to the Radius Anomalies of Transiting Giant Planets
Burrows, A; Budai, J D; Hubbard, W B
2006-01-01
We calculate the theoretical evolution of the radii of all fourteen of the known transiting extrasolar giant planets (EGPs) for a variety of atmospheric metallicities, dense inner core masses, and possible internal power sources. We incorporate the effects of stellar irradiation and customize such effects for each EGP and star. Looking collectively at the family as a whole, we find that there are in fact two radius anomalies to be explained. Not only are the radii of a subset of the known transiting EGPs larger than expected from previous theory, but many of the other objects are smaller than the default theory would allow. We suggest that the larger EGPs can be explained by invoking super-solar metallicity atmospheres and opacities that naturally retain internal heat and straightforwardly comport with the observed correlation between the statistics of EGPs and parent metallicity. This explanation might obviate the necessity for an extra internal power source. We explain the smaller radii by the presence in p...
Placing molecules with Bohr radius resolution using DNA origami
Funke, Jonas J.; Dietz, Hendrik
2016-01-01
Molecular self-assembly with nucleic acids can be used to fabricate discrete objects with defined sizes and arbitrary shapes. It relies on building blocks that are commensurate to those of biological macromolecular machines and should therefore be capable of delivering the atomic-scale placement accuracy known today only from natural and designed proteins. However, research in the field has predominantly focused on producing increasingly large and complex, but more coarsely defined, objects and placing them in an orderly manner on solid substrates. So far, few objects afford a design accuracy better than 5 nm, and the subnanometre scale has been reached only within the unit cells of designed DNA crystals. Here, we report a molecular positioning device made from a hinged DNA origami object in which the angle between the two structural units can be controlled with adjuster helices. To test the positioning capabilities of the device, we used photophysical and crosslinking assays that report the coordinate of interest directly with atomic resolution. Using this combination of placement and analysis, we rationally adjusted the average distance between fluorescent molecules and reactive groups from 1.5 to 9 nm in 123 discrete displacement steps. The smallest displacement step possible was 0.04 nm, which is slightly less than the Bohr radius. The fluctuation amplitudes in the distance coordinate were also small (±0.5 nm), and within a factor of two to three of the amplitudes found in protein structures.
Massive radius-dependent flow slippage in carbon nanotubes.
Secchi, Eleonora; Marbach, Sophie; Niguès, Antoine; Stein, Derek; Siria, Alessandro; Bocquet, Lydéric
2016-09-08
Measurements and simulations have found that water moves through carbon nanotubes at exceptionally high rates owing to nearly frictionless interfaces. These observations have stimulated interest in nanotube-based membranes for applications including desalination, nano-filtration and energy harvesting, yet the exact mechanisms of water transport inside the nanotubes and at the water-carbon interface continue to be debated because existing theories do not provide a satisfactory explanation for the limited number of experimental results available so far. This lack of experimental results arises because, even though controlled and systematic studies have explored transport through individual nanotubes, none has met the considerable technical challenge of unambiguously measuring the permeability of a single nanotube. Here we show that the pressure-driven flow rate through individual nanotubes can be determined with unprecedented sensitivity and without dyes from the hydrodynamics of water jets as they emerge from single nanotubes into a surrounding fluid. Our measurements reveal unexpectedly large and radius-dependent surface slippage in carbon nanotubes, and no slippage in boron nitride nanotubes that are crystallographically similar to carbon nanotubes, but electronically different. This pronounced contrast between the two systems must originate from subtle differences in the atomic-scale details of their solid-liquid interfaces, illustrating that nanofluidics is the frontier at which the continuum picture of fluid mechanics meets the atomic nature of matter.
Mass-Radius Relation of Strongly Magnetized White Dwarfs
Bera, P.; Bhattacharya, D.
2017-03-01
We study the strongly magnetized white dwarf configurations in a self-consistent manner as a progenitor of the over-luminous type-Ia supernovae. We compute static equilibria of white dwarf stars containing a strong magnetic field and present the modification of the white dwarf mass-radius relation caused by the magnetic field. From a static equilibrium study, we find that a maximum white dwarf mass of about 1.9 M⊙ may be supported if the interior poloidal field is as strong as approximately 1010 T. On the other hand if the field is purely toroidal the maximum mass can be more than 5 M⊙. All these modifications are mainly from the presence of the Lorenz force. The effects of i) modification of the equation of state due to Landau quantization, ii) electrostatic interaction due to ions, iii) general relativistic calculation on the stellar structure and, iv) field geometry are also considered. These strongly magnetised configurations are sensitive to magnetic instabilities where the perturbations grow at the corresponding Alfven time scales.
Mass-Radius Relation for Rocky Planets based on PREM
Zeng, Li; Jacobsen, Stein
2015-01-01
Several small dense exoplanets are now known, inviting comparisons to Earth and Venus. Such comparisons require translating their masses and sizes to composition models of evolved multi-layer-interior planets. Such theoretical models rely on our understanding of the Earth's interior, as well as independently derived equations of state (EOS), but have so far not involved direct extrapolations from Earth's seismic model -PREM. In order to facilitate more detailed compositional comparisons between small exoplanets and the Earth, we derive here a semi-empirical mass-radius relation for two-layer rocky planets based on PREM: ${\\frac{R}{R_\\oplus}} = (1.07-0.21\\cdot \\text{CMF})\\cdot (\\frac{M}{M_\\oplus})^{1/3.7}$, where CMF stands for Core Mass Fraction. It is applicable to 1$\\sim$8 M$_{\\oplus}$ and CMF of 0.0$\\sim$0.4. Applying this formula to Earth and Venus and several known small exoplanets with radii and masses measured to better than $\\sim$30\\% precision gives a CMF fit of $0.26\\pm0.07$.
Variation of Inner Radius of Dust Torus in NGC4151
Koshida, Shintaro; Kobayashi, Yukiyasu; Minezaki, Takeo; Sakata, Yu; Sugawara, Shota; Enya, Keigo; Suganuma, Masahiro; Tomita, Hiroyuki; Aoki, Tsutomu; Peterson, Bruce A
2009-01-01
The long-term optical and near infrared monitoring observations for a type 1 act ive galactic nucleus NGC 4151 were carried out for six years from 2001 to 2006 b y using the MAGNUM telescope, and delayed response of flux variations in the $K(2.2\\mu m)$ band to those in the $V(0.55\\mu m)$ band was clearly detected. Based on cross correlation analysis, we precisely measured a lag time $\\Delta t$ for eight separate periods, and we found that $\\Delta t$ is not constant changing be tween 30 and 70 days during the monitoring period. Since $\\Delta t$ is the ligh t travel time from the central energy source out to the surrounding dust torus, this is the first convincing evidence that the inner radius of dust torus did ch ange in an individual AGN. In order to relate such a change of $\\Delta t$ with a change of AGN luminosity $L$, we presented a method of taking an average of th e observed $V$-band fluxes that corresponds to the measured value of $\\Delta t$, and we found that the time-changing track of NGC 4151 in the...
Mass-Radius Relation for Rocky Planets Based on PREM
Zeng, Li; Sasselov, Dimitar D.; Jacobsen, Stein B.
2016-03-01
Several small dense exoplanets are now known, inviting comparisons to Earth and Venus. Such comparisons require translating their masses and sizes to composition models of evolved multi-layer interior planets. Such theoretical models rely on our understanding of the Earth’s interior, as well as independently derived equations of state, but so far have not involved direct extrapolations from Earth’s seismic model: the Preliminary Reference Earth Model (PREM). To facilitate more detailed compositional comparisons between small exoplanets and the Earth, we derive here a semi-empirical mass-radius relation for two-layer rocky planets based on PREM, \\frac{R}{{R}\\oplus }=(1.07-0.21\\cdot {CMF})\\cdot {≤ft(\\frac{M}{{M}\\oplus }\\right)}1/3.7, where CMF stands for core mass fraction. It is applicable to 1 ˜ 8 M⊕ and a CMF of 0.0 ˜ 0.4. Applying this formula to Earth and Venus and several known small exoplanets with radii and masses measured to better than ˜30% precision gives a CMF fit of 0.26 ± 0.07.
Massive radius-dependent flow slippage in carbon nanotubes
Secchi, Eleonora; Marbach, Sophie; Niguès, Antoine; Stein, Derek; Siria, Alessandro; Bocquet, Lydéric
2016-09-01
Measurements and simulations have found that water moves through carbon nanotubes at exceptionally high rates owing to nearly frictionless interfaces. These observations have stimulated interest in nanotube-based membranes for applications including desalination, nano-filtration and energy harvesting, yet the exact mechanisms of water transport inside the nanotubes and at the water-carbon interface continue to be debated because existing theories do not provide a satisfactory explanation for the limited number of experimental results available so far. This lack of experimental results arises because, even though controlled and systematic studies have explored transport through individual nanotubes, none has met the considerable technical challenge of unambiguously measuring the permeability of a single nanotube. Here we show that the pressure-driven flow rate through individual nanotubes can be determined with unprecedented sensitivity and without dyes from the hydrodynamics of water jets as they emerge from single nanotubes into a surrounding fluid. Our measurements reveal unexpectedly large and radius-dependent surface slippage in carbon nanotubes, and no slippage in boron nitride nanotubes that are crystallographically similar to carbon nanotubes, but electronically different. This pronounced contrast between the two systems must originate from subtle differences in the atomic-scale details of their solid-liquid interfaces, illustrating that nanofluidics is the frontier at which the continuum picture of fluid mechanics meets the atomic nature of matter.
Mass-radius relation of strongly magnetized white dwarfs
Bera, Prasanta; Bhattacharya, Dipankar
2016-07-01
We study the strongly magnetized white dwarf configurations in a self-consistent manner as a progenitor of the over-luminous type-Ia supernovae. We compute static equilibria of white dwarf stars containing a strong magnetic field and present the modification of white dwarf mass-radius relation caused by the magnetic field. From a static equilibrium study, we find that a maximum white dwarf mass of about 1.9 M_{⊙} may be supported if the interior poloidal field is as strong as approximately 10^{10} T. On the other hand, if the field is purely toroidal the maximum mass can be more than 5 M_⊙. All these modifications are mainly from the presence of Lorenz force. The effects of i) modification of equation of state due to Landau quantization ii) electrostatic interaction due to ions, ii) general relativistic calculation on the stellar structure and, iii) field geometry are also considered. These strongly magnetised configurations are sensitive to magnetic instabilities where the perturbations grow at the corresponding Alfven time scales.
Photospheric radius expansion in superburst precursors from neutron stars
Keek, L
2012-01-01
Thermonuclear runaway burning of carbon is in rare cases observed from accreting neutron stars as day-long X-ray flares called superbursts. In the few cases where the onset is observed, superbursts exhibit a short precursor burst at the start. In each instance, however, the data was of insufficient quality for spectral analysis of the precursor. Using data from the propane anti-coincidence detector of the PCA instrument on RXTE, we perform the first detailed time resolved spectroscopy of precursors. For a superburst from 4U 1820-30 we demonstrate the presence of photospheric radius expansion. We find the precursor to be 1.4-2 times more energetic than other short bursts from this source, indicating that the burning of accreted helium is insufficient to explain the full precursor. Shock heating would be able to account for the lacking energy. We argue that this precursor is a strong indication that the superburst starts as a detonation, and that a shock induces the precursor. Furthermore, we employ our techniq...
System Estimates Radius of Curvature of a Segmented Mirror
Rakoczy, John
2008-01-01
A system that estimates the global radius of curvature (GRoC) of a segmented telescope mirror has been developed for use as one of the subsystems of a larger system that exerts precise control over the displacements of the mirror segments. This GRoC-estimating system, when integrated into the overall control system along with a mirror-segment- actuation subsystem and edge sensors (sensors that measure displacements at selected points on the edges of the segments), makes it possible to control the GROC mirror-deformation mode, to which mode contemporary edge sensors are insufficiently sensitive. This system thus makes it possible to control the GRoC of the mirror with sufficient precision to obtain the best possible image quality and/or to impose a required wavefront correction on incoming or outgoing light. In its mathematical aspect, the system utilizes all the information available from the edge-sensor subsystem in a unique manner that yields estimates of all the states of the segmented mirror. The system does this by exploiting a special set of mirror boundary conditions and mirror influence functions in such a way as to sense displacements in degrees of freedom that would otherwise be unobservable by means of an edge-sensor subsystem, all without need to augment the edge-sensor system with additional metrological hardware. Moreover, the accuracy of the estimates increases with the number of mirror segments.
Closing capacity of segmental radius defects in rabbits.
Bodde, Esther W H; Spauwen, Paul H M; Mikos, Antonios G; Jansen, John A
2008-04-01
In the research of synthetic bone graft substitutes, the relevance for bone regeneration can be confirmed in a critical-sized model. In this study the rabbit radial defect was investigated as an ingenious model of critical size, due to its defect immobilizing intact ulna. In addition, the influence of poly(DL-lactic-co-glycolic acid) (PLGA) on bone regeneration was determined. Sixteen, 4-month-old rabbits received bilateral segmental radial defects of 15 or 20 mm. The osteotomy ends were marked with small titanium pins. Half of the group received injected PLGA microparticle/carboxymethylcellulose implants. Implantation time was 12 weeks. Evaluation consisted of radiographs after surgery and sacrifice, microcomputed tomography and histology. The radiographs revealed that the created defects were significantly smaller after sacrifice. Further a number of radii showed fibrocartilaginous interposition. Both findings indicated instability of the created defect. All evaluation techniques revealed that 15 and 20 mm were not of critical size, as most defects were more or less regenerated. PLGA microparticles did not influence bone regeneration significantly. In conclusion, 15- and 20-mm radius defects in 4-month-old rabbits were not a suitable model for bone regeneration as these defects were neither critical size nor stable. PLGA-microparticle degradation did not influence bone regeneration.
Mass-radius relations for helium white dwarfs
Civelek, R
1998-01-01
In recent years, white dwarf stars are receiving increasing attension. The recent studies on the relation of M-R for the WDs are those of Wood (1990), Vennes et al. (1995) and Althaus and Benvenuto (1997, 1998). Vennes et al. (1995) computed static M-R relation for masses between 0.4 $M_\\odot$ and 0.7 $M_\\odot$ assuming non zero temperature effects. They assumed the luminosity is proportional to the mass which works for cool WDs but their results are in the range of high effective temperatures. As Althaus and Benvenuto (1997) mentioned, luminosity is not proportional to a constant for hot WD interiors because of neutrino emission. The purpose of this study is to present the effect of neutrino emission at finite temperatures. We considered fully degenerate configuration for WDs with pure helium composition to obtain static mass-radius relation for masses greater than 0.4 $M_\\odot$ with luminosity mass ratio due to neutrino energy loss.
Photogrammetric analysis of the articular surface of the distal radius.
Ege, A; Seker, D Z; Tuncay, I; Duran, Z
2004-01-01
Three-dimensional measurements made using photogrammetry have recently gained popularity with the development of real-time detection facilities and up-to-date equipment. The modelling of human bones presents a particular challenge as the measurements required are difficult to obtain, especially from uneven surfaces. In this study, the articular surfaces of 12 radius bones were evaluated using photogrammetry to obtain three-dimensional coordinates of certain points. Morphometric characteristics of the digital topography of the articular surface were analysed using three-dimensional data from more than 200 points for each specimen. The coronal plane curve, from the tip of the styloid process to the centre of the distal radioulnar articular notch, was found to be similar to the fourth degree polynomial function. A mathematical expression representing the sagittal curve passing through scapholunate border could not be found. Close-range photogrammetry is a safe and precise technique that can provide reliable, reproducible and accurate data for evaluating complex morphological surfaces.
Volar morphology of the distal radius in axial planes: a quantitative analysis.
Oura, Keiichiro; Oka, Kunihiro; Kawanishi, Yohei; Sugamoto, Kazuomi; Yoshikawa, Hideki; Murase, Tsuyoshi
2015-04-01
To investigate the cause of rupture of the flexor pollicis longus (FPL) after volar plate fixation of distal radius fractures, previous studies have examined the shape of the distal radius in the sagittal plane or in the lateral view. However, there are no reports on the anatomical shape of the volar surface concavity of the distal radius in the axial plane. We hypothesized that this concavity might contribute to the mismatch between the plate and the surface of the radius. To test this hypothesis, we constructed three-dimensional models of the radius and FPL based on computed tomography scans of 70 normal forearms. We analyzed axial cross-sectional views with 2 mm intervals. In all cases, the volar surface of the distal radius was concave in the axial plane. The concavity depth was maximum at 6 mm proximal to the palmar edge of the lunate fossa and progressively decreased toward the proximal radius. FPL was closest to the radius at 2 mm proximal to the palmar edge of the lunate fossa. The volar surface of the distal radius was externally rotated from proximal to distal. These results may help to develop new implants which fit better to the radius and decrease tendon irritation.
Radius model of convex vertical curve of freeway based on attachment coefficient
LI Song-ling; PEI Yu-long
2008-01-01
A longitudinal slope brake model was established for the radius calculation of vertical curve of free-way through analyzing the dynamics of brake-running of vehicles running on the longitudinal slope road section. To satisfy the requirement of sight distance, a relation model was established for the attachment coefficient and the convex vertical curve radius. Using MATLAB simulation technique, the convex vertical curve radius at different attachment conditions was calculated accurately and a three-dimensional figure was drawn to describe the relation between the adhesive coefficient, the driving velocity and the radius of vertical curve. The correlation between the convex vertical curve radius and the adhesive coefficient was further analyzed and compared with National Technical Standards. The suggested radius of vertical curve was then put forward to provide a theoretical platform for the security design of the convex vertical curve.
Minimally invasive plate osteosynthesis for distal radius fractures
Xu-ming Wei
2014-01-01
Full Text Available Background: Fractures of distal radius are common injury in all age groups. Cast treatment with or without close reduction is a viable option. However, the results are often unsatisfactory with restricted function. The open reduction and internal fixation often results in extensive soft tissue dissection and associated high rates of infection and delayed/nonunion. The distractor/external fixator have reported good functional and anatomical results but the incidence of pin traction infection nerve injury and cosmedic deformity are high. We introduced a modified operative technique for minimally invasive plate osteosynthesis (MIPO for distal radial fracture and evaluated the functional outcomes and complications. Materials and Methods: 22 distal radial fractures (10 left, 12 right were treated using the MIPO technique and two small incisions with a palmar locking plate from August 2009 to August 2010. The wrist function was assessed according to Dienst wrist rating system, and postoperative complications were recorded. Results: According to Dienst wrist rating system, 13 patients showed excellent results, 6 cases showed good results and 3 patients had moderate results. No patient had poor results. Thus, the excellent and good rate was 86.4%. One patient had anesthesia in the thenar eminence and this symptom disappeared after 3 months. One patient had delayed healing in the proximal wrist crease. Two patients had mild pain on the ulnar side of the wrist and two patients had limited wrist joint function. Conclusion: The MIPO technique by using two small palmar incisions is safe and effective for treatment of distal radial fractures.
The strength of polyaxial locking interfaces of distal radius plates.
Hoffmeier, Konrad L; Hofmann, Gunther O; Mückley, Thomas
2009-10-01
Currently available polyaxial locking plates represent the consequent enhancement of fixed-angle, first-generation locking plates. In contrast to fixed-angle locking plates which are sufficiently investigated, the strength of the new polyaxial locking options has not yet been evaluated biomechanically. This study investigates the mechanical strength of single polyaxial interfaces of different volar radius plates. Single screw-plate interfaces of the implants Palmar 2.7 (Königsee Implantate und Instrumente zur Osteosynthese GmbH, Allendorf, Germany), VariAx (Stryker Leibinger GmbH & Co. KG, Freiburg, Germany) und Viper (Integra LifeSciences Corporation, Plainsboro, NJ, USA) were tested by cantilever bending. The strength of 0 degrees, 10 degrees and 20 degrees screw locking angle was obtained during static and dynamic loading. The Palmar 2.7 interfaces showed greater ultimate strength and fatigue strength than the interfaces of the other implants. The strength of the VariAx interfaces was about 60% of Palmar 2.7 in both, static and dynamic loading. No dynamic testing was applied to the Viper plate because of its low ultimate strength. By static loading, an increase in screw locking angle caused a reduction of strength for the Palmar 2.7 and Viper locking interfaces. No influence was observed for the VariAx locking interfaces. During dynamic loading; angulation had no influence on the locking strength of Palmar 2.7. However, reduction of locking strength with increasing screw angulation was observed for VariAx. The strength of the polyaxial locking interfaces differs remarkably between the examined implants. Depending on the implant an increase of the screw locking angle causes a reduction of ultimate or fatigue strength, but not in all cases a significant impact was observed.
2015-01-01
Bilateral distal radius fracture is a rare entity. There is no literature reporting a bilateral distal radius fracture in pregnancy. Fracture healing is influenced by hormones. Hormonal changes of pregnancy will affect the healing of a fracture. A 28-year-old female at 34 wk of pregnancy sustained a bilateral distal radius fracture after a self fall. One side was managed conservatively and open reduction was done for the other side. Both fractures united at four weeks. This case is unique in ...
Research on the expanding deformation of ring radius in cold profiled ring rolling process
无
2010-01-01
Cold profiled ring rolling is an advanced local plastic deformation technology widely used to precisely manufacture various complex seamless ring parts.It plays an important role in many industrial fields such as aeronautics,astronautics,automobile,bearings,etc.In the cold ring rolling process,the ring radius expands gradually with the increase of the feeding amount(i.e.rolling reduction),and the expanding deformation of the ring radius is closely related to the rolling reduction.It is very important to investigate the expanding deformation of ring radius for the precise control of ring dimensions and the design of feeding movement.In this paper,the relation between the expanding deformation of the ring radius and the rolling reduction in the stepped ring rolling process,a typical profiled ring rolling process,is analyzed by using analytical method.The results show that the growth amount of the filling depth of groove can’t exceed the rolling reduction,that in the inner stepped ring rolling process,the curves of the outer radius and big inner radius with the rolling reduction are monotonous,ascending and concave,i.e.,the outer radius and big inner radius expand faster and faster with the increase of the rolling reduction,and that in the outer stepped ring rolling process,the curves of the inner radius and small outer radius with the rolling reduction are also monotonous,ascending and concave,i.e.,the inner radius and small outer radius expand faster and faster with the increase of the roll reduction.
Posterolateral Elbow Dislocation with Ipsilateral Fractures of Head and Distal End Radius
Vijay C
2011-04-01
Full Text Available Elbow dislocation associated with ipsilateral fracture head and distal end radius is a rare pattern of Injury, although it is common for elbow dislocation and radius fractures to occur separately. We report a case of 35 year-old male who had a posterolateral elbow dislocation with ipsilateral fractures of head and distal end radius that underwent closed reduction and POP application and outcome is excellent with 9 months of follow-up.
Goberna, Miguel A.; Jeyakumar, Vaithilingam; Li, Guoyin; Linh, Nguyen
2016-01-01
The radius of robust feasibility of a convex program with uncertain constraints gives a value for the maximal ‘size’ of an uncertainty set under which robust feasibility can be guaranteed. This paper provides an upper bound for the radius for convex programs with uncertain convex polynomial constraints and exact formulas for convex programs with SOS-convex polynomial constraints (or convex quadratic constraints) under affine data uncertainty. These exact formulas allow the radius to be comput...
Brodie's abscess of the distal radius: an unusual complication after percutaneous pinning.
Johnson, Jeff W; Bindra, Randip R
2008-12-01
We report a case of Brodie's abscess of the distal radius that presented 4 years after closed reduction and percutaneous pinning for a closed distal radius fracture. This condition has not been previously reported in the adult distal radius and we detail the clinical features and imaging findings. We also present a new way of management of Brodie's abscess using injectable bone substitute along with adjunctive parenteral antibiotic therapy.
Brodie’s Abscess of the Distal Radius: An Unusual Complication after Percutaneous Pinning
Bindra, Randip R.
2008-01-01
We report a case of Brodie’s abscess of the distal radius that presented 4 years after closed reduction and percutaneous pinning for a closed distal radius fracture. This condition has not been previously reported in the adult distal radius and we detail the clinical features and imaging findings. We also present a new way of management of Brodie’s abscess using injectable bone substitute along with adjunctive parenteral antibiotic therapy. PMID:18780011
Fractures of the bilateral distal radius and scaphoid: a case report
Ozkan Korhan
2008-03-01
Full Text Available Abstract Introduction Bilateral fractures of the distal radius and scaphoid are extremely rare injuries. Case presentation A patient with bilateral comminuted, displaced distal fractures of the radius and bilateral fractures of the scaphoid was treated via internal fixation of the scaphoid fractures with Herbert screws and internal fixation of the distal radius fractures with locked volar plating. Conclusion Rigid internal fixation of distal radius and scaphoid fractures is mandatory to start early active rehabilitation of the wrist without the need for wrist immobilization with a plaster or external skeletal fixation.
Estimation of weapon-radius versus maneuverability trade-off for air-to-air combat
Kelley, H. J.; Lefton, L.
1977-01-01
A chase in a horizontal plane between a pursuer with a large capture radius and a more maneuverable evading vehicle is examined with constant-speed vehicle models. An approximation to the 'sidestepping' maneuver of the Homicidal Chauffeur Game is modified to account for the effect of evader turning rate, and an estimate of capture radius required is so obtained which agrees remarkably well with Cockayne's point-capture result. The maneuver assumes central importance for barrier surfaces appearing in the Game of Two Cars. Results are given for required weapon capture-radius in terms of the maneuverability of the two vehicles. Some calculations of capture radius are presented.
Evaluation of the proton charge radius from e-p scattering
Arrington, John
2015-01-01
In light of the proton radius puzzle, the discrepancy between measurements of the proton charge radius from muonic hydrogen and those from electronic hydrogen and electron-proton scattering measurements, we reexamine the charge radius extractions from electron scattering measurements. We provide a recommended value for the proton RMS charge radius, $r_E = 0.879 \\pm 0.011$ fm, based on a global examination of elastic e-p scattering data. The uncertainties include contributions to account for tension between different data sets and inconsistencies between radii using different extraction procedures.
Effects of Leading-Edge Radius on Aerodynamic Characteristics of 50º Delta Wings
Verhaagen, N.G.
2010-01-01
The study focuses on the effects of the leading-edge radius on the flow over 50º swept delta wing models. Three models were tested, one model having a sharp leading edge and the other two having a semi-circular leading edge of different radius. The vortical flow on and off the surface of the models
The Minimum Spectral Radius of Signless Laplacian of Graphs with a Given Clique Number
Su Li
2014-02-01
Full Text Available In this paper we observe that the minimal signless Laplacian spectral radius is obtained uniquely at the kite graph PKn−ω,ω among all connected graphs with n vertices and clique number ω. In addition, we show that the spectral radius μ of PKm,ω (m ≥ 1 satisfies
Osteonecrosis of the trapezium treated with a vascularized distal radius bone graft.
Zafra, Manuel; Carpintero, Pedro; Cansino, Daniel
2004-11-01
A 20-year-old man presented with early stage osteonecrosis of the trapezium, diagnosed by magnetic resonance imaging. A vascularized distal radius bone graft was performed, with good clinical and radiologic results over a 1-year follow-up period. The authors believe that a vascularized distal radius bone graft is an ideal treatment for early stage carpal bone necrosis.
Rieger, Michael; Gruber, Hannes; Jaschke, Werner R. [Innsbruck University Hospital, Department of Radiology I, Innsbruck (Austria); Gabl, Markus [Innsbruck University Hospital, Department of Trauma Surgery, Innsbruck (Austria); Mallouhi, Ammar [Innsbruck University Hospital, Department of Radiology II, Innsbruck (Austria)
2005-04-01
Our objective was to evaluate the usefulness of CT virtual preoperative planning in the surgical repositioning of malunited distal radius fracture. Eleven patients with malunited distal radius fracture underwent multislice CT of both wrists. A preoperative workup was performed in a virtual reality environment created from the CT data sets. Virtual planning comprised three main procedures, carrying out the virtual osteotomy of the radius, prediction of the final position of the distal radius after osteotomy and computer-assisted manufacturing of a repositioning device, which was later placed at the surgical osteotomy site to reposition objectively the distal radius fragment before fixation with the osteosynthesis. All patients tolerated the surgical procedure well. During surgery, the orthopedic surgeons were not required in any of the cases to alter the position of the distal radius that was determined by the repositioning device. At postoperative follow-up, the anatomic relationship of the distal radius was restored (radial inclination, 21.4 ; volar tilt, 10.3 ; ulnar variance, 0.5 mm). Clinically, a significant improvement of pronation (P=0.012), supination (P=0.01), flexion (P=0.001) and extension (P=0.006) was achieved. Pain decreased from 54 to 7 points. CT virtual reality is a valuable adjunct for the preoperative workup and surgical reposition of malunited distal radius fractures. (orig.)
A Precise Asteroseismic Age and Radius for the Evolved Sun-like Star KIC 11026764
Metcalfe, Travis S.; Monteiro, Mario J.P.F.G.; Thompson, Michael J.
2010-01-01
that attempt to match the asteroseismic and spectroscopic constraints simultaneously. We determine both the radius and the age of KIC 11026764 with a precision near 1%, and an accuracy near 2% for the radius and 15% for the age. Continued observations of this star promise to reveal additional oscillation...
Any lure’s semiochemical release rate that is attractive to flying insects has a specific effective attraction radius (EAR) that corresponds to the lure’s orientation response strength. The EAR was defined as the radius of a passive sphere that would intercept the same number of insects as a semioch...
Collision free path generation in 3D with turning and pitch radius constraints for aerial vehicles
Schøler, F.; La Cour-Harbo, A.; Bisgaard, M.
2009-01-01
assumes that most of the aircraft structural and dynamic limitations can be formulated as a turn radius constraint, and that any two consecutive waypoints have line-of-sight. The generated trajectories are collision free and also satisfy a constraint on the minimum admissible turning radius, while...
The Muon Scattering Experiment (MUSE at PSI and the proton radius puzzle
Kohl Michael
2014-01-01
Full Text Available The unexplained large discrepancy of the proton charge radius measurements with muonic hydrogen Lamb shift and determinations from elastic electron scattering and Lamb shift in regular hydrogen of seven standard deviations is known as the proton radius puzzle. Suggested solutions of the puzzle range from possible errors in the experiments through unexpectedly large hadronic physics effects to new physics beyond the Standard Model. A new approach to verify the radius discrepancy in a systematic manner will be pursued with the Muon Scattering Experiment (MUSE at PSI. The experiment aims to compare elastic cross sections, the proton elastic form factors, and the extracted proton charge radius with scattering of electrons and muons of either charge and under identical conditions. The difference in the observed radius will be probed with a high precision to verify the discrepancy. An overview of the experiment and the current status will be presented.
Vertical profiles of droplet effective radius in shallow convective clouds
S. Zhang
2011-05-01
Full Text Available Conventional satellite retrievals can only provide information on cloud-top droplet effective radius (r_{e}. Given the fact that cloud ensembles in a satellite snapshot have different cloud-top heights, Rosenfeld and Lensky (1998 used the cloud-top height and the corresponding cloud-top r_{e} from the cloud ensembles in the snapshot to construct a profile of r_{e} representative of that in the individual clouds. This study investigates the robustness of this approach in shallow convective clouds based on results from large-eddy simulations (LES for clean (aerosol mixing ratio N_{a} = 25 mg^{−1}, intermediate (N_{a} = 100 mg^{−1}, and polluted (N_{a} = 2000 mg^{−1} conditions. The cloud-top height and the cloud-top r_{e} from the modeled cloud ensembles are used to form a constructed r_{e} profile, which is then compared to the in-cloud r_{e} profiles. For the polluted and intermediate cases where precipitation is negligible, the constructed r_{e} profiles represent the in-cloud r_{e} profiles fairly well with a low bias (about 10 %. The method used in Rosenfeld and Lensky (1998 is therefore validated for nonprecipitating shallow cumulus clouds. For the clean, drizzling case, the in-cloud r_{e} can be very large and highly variable, and quantitative profiling based on cloud-top r_{e} is less useful. The differences in r_{e} profiles between clean and polluted conditions derived in this manner are however, distinct. This study also investigates the subadiabatic characteristics of the simulated cumulus clouds to reveal the effect of mixing on r_{e} and its evolution. Results indicate that as polluted and moderately polluted clouds develop into their decaying stage, the subadiabatic fraction
Evolution of the solar radius during the solar cycle 24 rise time
Meftah, Mustapha
2015-08-01
One of the real motivations to observe the solar radius is the suspicion that it might be variable. Possible temporal variations of the solar radius are important as an indicator of internal energy storage and as a mechanism for changes in the total solar irradiance. Measurements of the solar radius are of great interest within the scope of the debate on the role of the Sun in climate change. Solar energy input dominates the surface processes (climate, ocean circulation, wind, etc.) of the Earth. Thus, it appears important to know on what time scales the solar radius and other fundamental solar parameters, like the total solar irradiance, vary in order to better understand and assess the origin and mechanisms of the terrestrial climate changes. The current solar cycle is probably going to be the weakest in 100 years, which is an unprecedented opportunity for studying the variability of the solar radius during this period. This paper presents more than four years of solar radius measurements obtained with a satellite and a ground-based observatory during the solar cycle 24 rise time. Our measurements show the benefit of simultaneous measurements obtained from ground and space observatories. Space observations are a priori most favourable, however, space entails also technical challenges, a harsh environment, and a finite mission lifetime. The evolution of the solar radius during the rising phase of the solar cycle 24 show small variations that are out of phase with solar activity.
Anatomical variations of the proximal radius and their effects on osteosynthesis.
Giannicola, Giuseppe; Manauzzi, Erica; Sacchetti, Federico M; Greco, Alessandro; Bullitta, Gianluca; Vestri, Annarita; Cinotti, Gianluca
2012-05-01
In fractures of the radial head and neck requiring open reduction and internal fixation, osteosynthesis may be safely applied in a limited zone. We conducted a morphometric study of the proximal radius at the level of the safe zone to identify different morphologic types of this anatomical region. We analyzed 44 dried cadaveric radii. We measured the whole length of the radius, the length of the neck and head, and the minimum and maximum diameter of the radial head. The morphologic aspect of the neck-head curvature of the safe zone was evaluated qualitatively and quantitatively. The proximal radius at the level of the safe zone exhibited different radii of bending. In particular, we identified a morphologic type A, which showed a flat profile (25% of cases), morphologic types B and C, which showed a low concave curvature (64%), and a marked concave curvature (11%), respectively, of the safe zone. The profile of the proximal radius in the safe zone shows substantial morphologic variations that should be taken into account when operating on fractures of the proximal radius, to avoid malunions, pain, and stiffness of the elbow joint. A preoperative radiograph of the contralateral uninjured radius may be helpful in selecting the most appropriate internal fixation device to reconstruct the proximal radius after comminuted fractures. Knowledge of the proper bending radius of the safe zone allows the surgeon to select the most appropriate plate, and to achieve good fracture reduction and anatomical restoration of the proximal radius. Copyright © 2012 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.
Initialization effects via the nuclear radius on transverse in-plane flow and its disappearance
Bansal Rajni
2014-04-01
Full Text Available We study the dependence of collective transverse flow and its disappearance on initialization effects via the nuclear radius within the framework of the Isospin-dependent Quantum Molecular Dynamics (IQMD model. We calculate the balance energy using different parametrizations of the radius available in the literature for the reaction of 12C+12C to explain its measured balance energy. A mass-dependent analysis of the balance energy through out the periodic table is also carried out by changing the default liquid drop IQMD radius.
Use of High-Speed X ray and Video to Analyze Distal Radius Fracture Pathomechanics.
Gutowski, Christina; Darvish, Kurosh; Liss, Frederic E; Ilyas, Asif M; Jones, Christopher M
2015-10-01
The purpose of this study is to investigate the failure sequence of the distal radius during a simulated fall onto an outstretched hand using cadaver forearms and high-speed X ray and video systems. This apparatus records the beginning and propagation of bony failure, ultimately resulting in distal radius or forearm fracture. The effects of 3 different wrist guard designs are investigated using this system. Serving as a proof-of-concept analysis, this study supports this imaging technique to be used in larger studies of orthopedic trauma and protective devices and specifically for distal radius fractures.
Hyperextension trauma to the elbow joint induced through the distal ulna or the distal radius
Tyrdal, Stein; Olsen, Bo Sanderhoff
1998-01-01
Loads applied to the forearm result in hyperextension of the elbow. The pathomechanics of hyperextension trauma with load applied to the distal radius and ulna were studied in 10 macroscopically normal cadaver elbow joint specimens to reveal patterns of injury with radial traction (n = 5) compared...... trauma to the elbow joint induced through the distal ulna or the distal radius produced the same pattern of injury as reported in hyperextension of the elbow with traction to the forearm when free rotation of the radius relative to the ulna was allowed....
The Effect of Osteoporosis on Healing of Distal Radius Fragility Fractures.
Tulipan, Jacob; Jones, Christopher M; Ilyas, Asif M
2015-10-01
Although the decision for operative versus nonoperative treatment of distal radius fractures remains subjective and is performed on a case-by-case basis, evaluation and treatment of patients with concomitant osteoporosis requires understanding of the behavior of this injury as a distinct subset of distal radius fractures. Age, infirmity, and osteoporosis affect every aspect of the fracture. Understanding what makes these fractures unique assists surgeons in more effective and efficient treatment. The authors present the current understanding of osteoporotic fragility fractures of the distal radius, focusing on epidemiology, biomechanics of bone healing, and its implication on strategies for management.
Synchronous Multicentric Giant Cell Tumour of Distal Radius and Sacrum with Pulmonary Metastases
Varun Sharma Tandra
2015-01-01
Full Text Available Giant cell tumour (GCT is an uncommon primary bone tumour, and its multicentric presentation is exceedingly rare. We report a case of a 45-year-old female who presented to us with GCT of left distal radius. On the skeletal survey, osteolytic lesion was noted in her right sacral ala. Biopsy confirmed both lesions as GCT. Pulmonary metastasis was also present. Resection-reconstruction arthroplasty for distal radius and thorough curettage and bone grafting of the sacral lesion were done. Multicentric GCT involving distal radius and sacrum with primary sacral involvement is not reported so far to our knowledge.
Research of RADIUS in access convergence router%RADIUS协议在ACR中的研究
单康康; 张兴明
2011-01-01
针对大规模接入汇聚路由器(ACR)可运营的要求,根据ACR用户实际业务需求提出了在ACR中利用远程用户拨号认证协议(RADIUS)实现AAA的方案,制定了相应的RADIUS报文数据项,最后给出了RADIUS单元模块的实现.%To fulfil the operational requirements of the Access Convergence Router (ACR) , a method in which RADIUS is incorperated into the ACR to better serve the actual needs of users and facilitate an AAA scheme, is proposed. This paper also presents the related attributes of RADIUS packets. Finally, the realization of RADIUS module is presented.
Asymptotic Normalization Coefficient of 27P→26Si+p and Radius of 27P Halo
GUO Bing; LI Zhi-Hong; LIU Wei-Ping; BAI Xi-Xiang
2006-01-01
The asymptotic normalization coefficient of the virtual decay 27P→26Si+p is extracted to be 1840±240 fm-1 from the peripheral 26Mg(d,p)27Mg reaction using charge symmetry of mirror pair,for the first time.It is then used to derive the rms radius of the valence proton in the ground state of 27P.We obtain the rms radius 1/2=4.57±0.36 fm,significantly larger than the matter radius of 27P.The probability of the valence proton outside the matter radius of 27P is found to be 73%.The present work supports the conclusion that the 27P ground state has a proton halo structure.
Ambipolar Diffusion in Direct-Current Positive Column with Variations in Radius of Discharge Tube
D. AKBAR; S. BILIKMEN
2006-01-01
@@ The ambipolar diffusion and argon ion mobility as functions of the reduced electric field and pressure times the tube radius are investigated in a weakly ionized non-uniform glow discharge plasma system.
Mitigation Effect of Finite Larmor Radius on Rayleigh-Taylor Instability in Z-Pinch Implosions
邱孝明; 黄林; 简广德
2002-01-01
Based on the framework of magnetohydrodynamic theory, a simple model is proposed to study the mitigation effect of finite Larmor radius on the Rayleigh-Taylor instability in Z-pinch implosions. In this model, taking account of Ti ≥ Te in Z-pinch implosions we believe that the magnetohydrodynamic plasma responds to a perturbation (～ exp [i (k. x - ωt)]) at frequency (ω + ik2⊥ρ2iΩi) instead of frequency ω, where k2⊥ρ2i is due to the finite Larmor radius effects expressed from the generalkinetic theory of magnetized plasma. Therefore the linearized continuity and momentum equations for the perturbed mass-density and velocity include the finite Larmor radius effects. The calculations indicate that, in the wavenumber region of interest, the finite Larmor radius effects can mitigate the Rayleigh-Taylor instability in Z-pinch implosions.
Water Well Locations - MO 2010 Public Water System Wells Half-Mile Radius (SHP)
NSGIC GIS Inventory (aka Ramona) — This shapefile represents a one-half mile radius around public water system (PWS) wells. This data set does not include wells classified as plugged, observation,...
Optimization research of sextant fan baffle curvature radius in shell and tube heat exchanger
Jin, M.; Liu, H. J.; Wang, X. Y.
2017-09-01
For a high shell side pressure drop of the conventional segmental baffles in shell and tube heat exchanger, a novel sextant fan baffle was put forward. To research the influence of baffle curvature radius of the sextant fan baffled shell and tube heat exchanger (SFTHX) on the shell side pressure drop, the heat transfer coefficient and the comprehensive heat transfer performance, six different curvature radius baffles were numerically simulated and experimental studied in this paper. Based on the numerically simulation results, under the same inlet flow conditions, a better comprehensive heat transfer performance can be found in SFTHX with the baffle curvature radius of 1 D, which is higher by 0.84-6.85% more than that of the others. Moreover, the experimental investigation data of SFTHX with baffle curvature radius of 1 D indicates that the numerically simulation can well predict the flow and heat transfer characteristics with the experiment.
Ruoff, A L; Christensen, N E
2002-01-01
By calculating the single-crystal elastic constants of W and Mo by first-principles methods the pressure strengthening of the yield stress was obtained. This was used to calculate the behaviour of the hydrogen sample hole size in a tungsten gasket. It was found that drastic changes occur depending on r sub s sup 0 /r sub t where r sub s sup 0 is the initial sample radius and r sub t is the diamond tip radius. It is seen why, with r sub s sup 0 /r sub t =0.9, the Carnegie group cannot and have not exceeded pressures of 230 GPa and why, with r sub s sup 0 /r sub t =0.5, the Cornell group has been able to reach 342 GPa.
Distal radius fracture after Sauvé-Kapandji procedure in a rheumatoid arthritis patient.
Ochi, Kensuke; Horiuchi, Yukio; Matsumura, Takashi; Nakamura, Mitsukazu; Takei, Terue; Yabe, Hiroki
2012-04-01
We report a case of distal radius fracture after a Sauvé-Kapandji procedure combined with synovectomy and tendon transfer in a rheumatoid arthritis patient. This case shared several unusual features that were also seen in a previously reported case. Based on these features, we discuss favorable surgical treatment for the rheumatoid wrist with extensor tendon rupture, and also the optimal treatment for distal radius fracture after such procedures.
indications of r-mode oscillations in soho/mdi solar radius measurements
Sturrock, P A; Gough, D O; Scargle, J D
2015-01-01
Analysis of solar radius measurements acquired by the Michelson Doppler Imager on the SOHO spacecraft supports previously reported evidence of solar internal r-mode oscillations in Mt Wilson radius data and in nuclear-decay data acquired at the Lomonosov Moscow State University. The frequencies of these oscillations are compatible with oscillations in a putative inner tachocline that separates a slowly rotating core from the radiative envelope.
Bahari, Syah
2007-07-01
Fracture of the distal radius from low energy trauma is a common presentation to orthopaedic trauma services. This fragility type fracture is associated with underlying osteoporosis. Osteoporosis is a \\'silent disease\\' where fragility fracture is a common presentation. Orthopaedic surgeons may be the only physician that these patients encounter. We found a high percentage of female patients who sustained a fragility fracture of the distal radius have an underlying osteoporosis. Further management of osteoporosis is important to prevent future fragility fractures.
Effect of the Finite Ion Larmor Radius on the Kelvin‐Helmholtz Instability
Melchior, Henning; Popovich, M.
1968-01-01
The Kelvin‐Helmholtz instability is described with the effects of the finite ion Larmor radius included. The growth rate is computed for several values of the velocity shear and different density profiles. © 1968 American Institute of Physics......The Kelvin‐Helmholtz instability is described with the effects of the finite ion Larmor radius included. The growth rate is computed for several values of the velocity shear and different density profiles. © 1968 American Institute of Physics...
Inequalities on the Inner Radius of Univalency and the Norm of Pre-Schwarzian Derivative
Tao CHENG; Yue Ming KANG; Ji Xiu CHEN
2009-01-01
In this paper, we get a lower bound of inner radius of univalency of Schwarzian derivative by means of the norm of pre-Schwarzian derivative. Furthermore, we apply the theory of Universal Teichmuller Space to explain its geometric meaning which shows the relationship between the inner radius in Universal Teichmuller Space embedded by Schwarzian derivative and the norm defined in Universal Teichmuller Space embedded by pre-Schwarzian derivative.
MD simulation of the effect of contact area and tip radius on nanoindentation
CHEN; Shangda; KE; Fujiu
2004-01-01
Molecular dynamics simulations of nanoindentation are performed on monocrystal copper. A new "contact atoms" method is presented for calculating the contact area. Compared with conventional methods, this method can provide the contact area more accurately not only for sink-in but also for pile-up situation. The effect of tip radius on indentation is investigated too. The results indicate that the measured hardness of the material will become higher as the tip radius increases.
Carpal tunnel syndrome: A rare manifestation of distal radius osteoid osteoma.
Basran, Sukhvinder Singh; Kumar, Sandeep; Jameel, Javed; Sajid, Imran
2015-09-01
Osteoid Osteoma is a benign bone tumor that normally affects long bones and rarely affects distal radius. Because of its nonspecific presentation in the wrist, it remains a diagnostic challenge. We report an unusual case of Osteoid Osteoma at distal radius having symptoms resembling that of carpal tunnel syndrome. The diagnosis was confirmed preoperatively with X-rays; bone scintigraphy, CT, and MRI, later histological examination confirmed the diagnoses. Surgical excision lead to a dramatic improvement in the condition of the patient.
Di Lorenzo, N; Camperchioli, I; Gaspari, A L
2007-12-01
We illustrate our experience with a new class of instruments, the mechanical manipulators (MM), whose main features are an improved mobility, and ergonomy and a modular structure. A specific MM, the Radius Surgical System (RADIUS), has been used both for educational purposes as well as in clinical studies, demonstrating that it can represent an efficient tool to support surgeons performing surgical complex procedures, with a short learning curve for the postural attitude.
Mass-Radius Relations of Z and Higgs-Like Bosons
Lehnert B.
2014-01-01
Full Text Available Relations between the rest mass and the effective radius are deduced for the Z boson and the experimentally discovered Higgs-like boson, in terms of a revised quantum electrodynamic (RQED theory. The latter forms an alternative to the Standard Model of elementary particles. This results in an effective radius of the order of 10 E-18 m for a rest mass of 125 GeV.
Tonogai, Ichiro; Hamada, Yoshitaka; Hibino, Naohito; Sato, Ryosuke; Henmi, Tatsuhiko; Sairyo, Koichi
2015-01-01
Salmonella osteomyelitis of the radius in a healthy individual is very rare. We present such a case involving the distal radius of a healthy 23-year-old man without underlying disease or possible episode...
Status of the MUSE Measurement of the Proton Radius at PSI
Gilman, Ronald; MUSE Collaboration
2014-09-01
It is a puzzle that the proton radius appears to be different when measured with muons vs. with electrons. The MUon Scattering Experiment (MUSE) at the Paul Scherrer Institut (PSI) πM1 beam line utilizes a mixed e / μ / π beam to measure μ+/- p and e+/- p elastic scattering. The experiment will study the proton electromagnetic form factors at low Q2, in the region most sensitive to the proton radius. The goal is to determine whether the charge radius is indeed the same for muons and electrons, with measurements at the same time in a single experiment. I will describe test measurements done for the MUSE experiment and discuss the status of the project. It is a puzzle that the proton radius appears to be different when measured with muons vs. with electrons. The MUon Scattering Experiment (MUSE) at the Paul Scherrer Institut (PSI) πM1 beam line utilizes a mixed e / μ / π beam to measure μ+/- p and e+/- p elastic scattering. The experiment will study the proton electromagnetic form factors at low Q2, in the region most sensitive to the proton radius. The goal is to determine whether the charge radius is indeed the same for muons and electrons, with measurements at the same time in a single experiment. I will describe test measurements done for the MUSE experiment and discuss the status of the project. This work was supported in part by the US National Science Foundation Grant PHY 1306126.
Tv, Ravikumar; P, Rahul; Grover, Amit; Samorekar, Bheemsingh
2015-04-01
Bilateral distal radius fracture is a rare entity. There is no literature reporting a bilateral distal radius fracture in pregnancy. Fracture healing is influenced by hormones. Hormonal changes of pregnancy will affect the healing of a fracture. A 28-year-old female at 34 wk of pregnancy sustained a bilateral distal radius fracture after a self fall. One side was managed conservatively and open reduction was done for the other side. Both fractures united at four weeks. This case is unique in three ways. First distal radius fractures commonly occur in elderly postmenopausal females due to oestrogen deficiency. In this case a distal radius fracture occurred following a self fall in third trimester of pregnancy - a hyperestrogenic state. Second the time taken for union was only four weeks signifying the hormonal effects on pregnancy on fracture healing. Third the occurrence of bilateral distal radius fracture itself is very rare in adults. In pregnancy there is a faster rate of fracture healing due to effects of oestrogen and increased cardiac output. Fractures in pregnancy require special attention. Surgical intervention should be done with a multidisciplinary approach. While management of fractures in pregnancy, effect of hormonal and physiological changes should be kept in mind.
Measurement of the radius of Mercury by radio occultation during the MESSENGER flybys
Perry, Mark E.; Kahan, Daniel S.; Barnouin, Olivier S.; Ernst, Carolyn M.; Solomon, Sean C.; Zuber, Maria T.; Smith, David E.; Phillips, Roger J.; Srinivasan, Dipak K.; Oberst, Jürgen; Asmar, Sami W.
2011-12-01
The MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft completed three flybys of Mercury in 2008-2009. During the first and third of those flybys, MESSENGER passed behind the planet from the perspective of Earth, occulting the radio-frequency (RF) transmissions. The occultation start and end times, recovered with 0.1 s accuracy or better by fitting edge-diffraction patterns to the RF power history, are used to estimate Mercury's radius at the tangent point of the RF path. To relate the measured radius to the planet shape, we evaluate local topography using images to identify the high-elevation feature that defines the RF path or using altimeter data to quantify surface roughness. Radius measurements are accurate to 150 m, and uncertainty in the average radius of the surrounding terrain, after adjustments are made from the local high at the tangent point of the RF path, is 350 m. The results are consistent with Mercury's equatorial shape as inferred from observations by the Mercury Laser Altimeter and ground-based radar. The three independent estimates of radius from occultation events collectively yield a mean radius for Mercury of 2439.2±0.5 km.
Die Radius Affecting Sheet Metal Extrusion Quality for Fine Blanking Process
Chatkaew Suriyapha
2010-01-01
Full Text Available Problem statement: Sheet metal extrusion is a process in which the punch penetrates one surface of the sheet metal material to cause it to extrude and flow toward the outlet of the die. Therefore, the process can invent different thickness of sheet metal work piece. From these advantages on the sheet metal extrusion, nowadays, it is generally used in many manufacturing of industrial elements fields. The Sheet Metal Extrusions in Fine Blanking (SME-FB advantages, over a conventional extrusion, are possible due to a blank holder force, a counterpunch force and a large die radius. However, the selection on those parameter values affects on the material flow and the surface quality on the extrusion parts also. Namely, it causes the crack surface and shrinkage failure which are the general problems in the SME-FB. Approach: Objective of this research was to study the effect of die radius on the SME-FB surface which investigated the formation of the failure defection with respect to the several die radiuses by using the Finite Element Method (FEM. Results: From the results, it indicated that applying the small die radius caused the material flow difficult resulting in the decreasing of smooth surface. Vice versa, in the case of large die radius, the material flow easy is resulting in the increasing of smooth surface. Conclusion: The FEM simulation results of a larger die radius will cause the residual stress at work piece.
The Mass-Radius Relation Between 60 Exoplanets Smaller than 4 Earth Radii
Weiss, Lauren M
2013-01-01
We study the masses and radii of 60 exoplanets smaller than 4 Earth radii with orbital periods shorter than 100 days. We find a nearly linear mass-radius relation: M/M_E= 3.17 (R/R_E)^0.87, which is a shallower power-law index than in many previous mass-radius relations. The RMS of planet masses to this fit is 3.9 Earth masses, and our best fit has reduced chi squared = 3.1, indicating a diversity in planet compositions below 4 Earth radii. Fitting density vs. radius with a polynomial, we find planet density = 11.50 - 5.97 (R/R_E) + 0.84 (R/R_E)^2. The mass-radius and mass-density relations reflect that planet density decreases as radius increases, indicating that larger exoplanets have a significant fraction of volatiles by volume (such as H/He envelopes). Exoplanets have densities comparable to that of Earth at R = 1.5 R_E, indicating likely rocky compositions among planets smaller than 1.5 Earth radii. The scaling of the mass-radius relationship for exoplanets smaller than 1.5 Earth radii is not well-const...
Corrective distal radius osteotomy: including bilateral differences in 3-D planning.
Dobbe, J G G; Vroemen, J C; Strackee, S D; Streekstra, G J
2013-07-01
After a fracture of the distal radius, the bone segments may heal in a suboptimal position. This condition may lead to a reduced hand function, pain and finally osteoarthritis, sometimes requiring corrective surgery. Recent studies report computer-assisted 3-D planning techniques in which the mirrored contralateral unaffected radius serves as reference for planning the position of the distal radius before corrective osteotomy surgery. Bilateral asymmetry, however, may introduce length errors into this type of preoperative planning that can be compensated for by taking into account the concomitant ulnae asymmetry. This article investigates a method for planning a correction osteotomy of the distal radius, while compensating for bilateral length differences using a linear regression model that describes the relationship between radii and ulnae asymmetry. The method is evaluated quantitatively using CT scans of 20 healthy individuals, and qualitatively using CT scans of patients suffering from a malunion of the distal radius. The improved planning method reduces absolute length deviations by a factor of two and markedly reduces positioning variation, from 2.9 ± 2.1 to 1.5 ± 0.6 mm. We expect the method to be of great value for future 3-D planning of a corrective distal radius osteotomy.
ACS imaging of star clusters in M51. I. Identification and radius distribution
Scheepmaker, R A; Gieles, M; Bastian, N; Larsen, S S; Lamers, Henny J G L M
2007-01-01
We use HST/ACS observations of the spiral galaxy M51 in F435W, F555W and F814W to select a large sample of star clusters with accurate effective radius measurements in an area covering the complete disc of M51. We present the dataset and study the radius distribution and relations between radius, colour, arm/interarm region, galactocentric distance, mass and age. We select a sample of 7698 (F435W), 6846 (F555W) and 5024 (F814W) slightly resolved clusters and derive their effective radii by fitting the spatial profiles with analytical models convolved with the point spread function. The radii of 1284 clusters are studied in detail. We find cluster radii between 0.5 and ~10 pc, and one exceptionally large cluster candidate with a radius of 21.6 pc. The median radius is 2.1 pc. We find 70 clusters in our sample which have colours consistent with being old GC candidates and we find 6 new "faint fuzzy" clusters in, or projected onto, the disc of M51. The radius distribution can not be fitted with a power law, but ...
[The Study of relationship between fetal radius loss and chromosomal abnormality].
Yang, R Q; Liu, Z Y; Hu, J; Nan, Y; Fan, L M
2016-09-20
Objective: To explore the relationship between fetal radius loss and chromosomal abnormalities. Methods: Collect data of 3 100 cases pregnant women who had been checked in the second hospital of Jilin University from 2012 to 2015.There were 8 cases of absent radius, except 1 case of fetal lost follow-up, the remaining 7 cases had complete ultrasound, chromosome examination and the result of induction.The relationship between fetal radius loss and chromosomal abnormalities were analysed. Results: There were 1 case of 21 trisomy syndrome, 1 case of trisomy 13 syndrome, 2 cases of trisomy 18, 2 cases of chromosome translocation, 1 case of normal chromosome result and 1 case was lost to follow-up of the 8 absent radius fetuses. Conclusion: Through a comparison between the chromosome and ultrasonic characteristics of fetuses who have absent radius, we had indicated the relationship of fetal radius deletion and chromosomal anomaly, improved the positive rate of chromosome invasion examination, and provided the reference for eugenics.
Accuracy and analysis of long-radius measurement with long trace profiler
Haixian Ye; Liming Yang
2011-01-01
The long trace profiler (LTP) is proposed to measure radius of curvature (R) and surface figure of a long-radius spherical surface in an optical shop. Equipped with a motorized rotary stage and a two-dimensional tilt stage, the LTP scans the full aperture and calculates the absolute radius of curvature of each scanning line based on the least square method. Nonlinear error and manufacture error difference between (-enter and the edge are obtained by comparing R results. The R-limit is validated and expressed as D/R, where D is the aperture of the mirror under tost. A full-aperture three-dimensional figure is also reconstructed based on triangle interpolation.%The long trace profiler (LTP) is proposed to measure radius of curvature (R) and surface figure of a longradius spherical surface in an optical shop.Equipped with a motorized rotary stage and a two-dimensional tilt stage,the LTP scans the full aperture and calculates the absolute radius of curvature of each scanning line based on the least square method.Nonlinear error and manufacture error difference between center and the edge are obtained by comparing R results.The R-limit is validated and expressed as D/R,where D is the aperture of the mirror under test.A full-apertnre three-dimensional figure is also reconstructed based on triangle interpolation.Large optical observing systeus and hngc 1aser installations demand numerons large-scale spherical and aspherical lenses with loug focal length.Array laser installatinns,in particular,strictly demand consistency of focal length.Metrology for long focal length lens has considerable influence on the performance of these optical systems.Focal length can be calculated from the radius of curvature.Thus,developing an instrument for direct long-radius surface measurement tan ensure precision of the long focal length and improve manufacturing efficiency.
Ehlers, R.; Picksak, A.; Krueger, V.; Witte, J. (Eastman Teleco, Celle (Germany))
1992-10-01
Horizontal technology proved to be a very effective method to improve recovery from old reservoirs besides other methods of enhanced oil recovery. Since the introduction of steerable short radius drilling systems in 1989, the industry holds now the ability to drill horizontal intervals exeeding 300 m below a 12 m radius curve. The system's main components are an articulated downhole motor and a flexible wireline steering tool. The achieved results confirmed the new system's efficiency. Flexible MWDs are currently under extensive field testing and will provide the necessary member for a modern steerable drilling system. Following an introduction to the drilling system, recent case histories from Italy and the Middle East are presented. A future outlook and further applications are given. (orig.).
Tatewaki, Hiroshi, E-mail: htatewak@nsc.nagoya-cu.ac.jp [Graduate School of Natural Sciences, Nagoya City University, Nagoya, Aichi 467-8501 (Japan); Institute of Advanced Studies in Artificial Intelligence, Chukyo University, Toyota, Aichi 470-0393 (Japan); Hatano, Yasuyo [School of Information Science and Technology, Chukyo University, Toyota, Aichi 470-0393 (Japan); Noro, Takeshi [Division of Chemistry, Graduate School of Science, Hokkaido University, Sapporo, Hokkaido 060-0810 (Japan); Yamamoto, Shigeyoshi [School of International Liberal Studies, Chukyo University, Nagoya, Aichi 466-8666 (Japan)
2015-06-15
We consider, for atoms from {sub 55}Cs to {sub 80}Hg, the effective atomic radius (r{sub ear}), which is defined as the distance from the nucleus at which the magnitude of the electric field is equal to that in He at one half of the equilibrium bond length of He{sub 2}. The values of r{sub ear} are about 50% larger than the mean radius of the outermost occupied orbital of 6s,
无
2003-01-01
A hybrid model of MHD and kinetic theory is proposed to investigate the synergetic stabilizing effects of sheared axial flow and finite Larmor radius on the Rayleigh-Taylor instability in Z-pinch implosions.In our model the MHD plasma is considered to respond to a perturbation with exp[i(k*x-ωt)] at frequency ω+ik2⊥ρ2iΩi instead of frequency ω,where k2⊥ρ2i is the finite Larmor radius effects given from the general kinetic theory of magnetized plasma.Therefore linearized continuity and momentum equations include automatically the finite Larmor radius effects.Dispersion relation is derived,which includes the effects of a density discontinuity and the finite Larmor radius as well as a sheared flow that produces the Kelvin-Helmholtz instability.The dispersion equation is examined in three cases.The results indicate that the synergetic effect of sheared axial flow and the finite Larmor radius can mitigate both the Rayleigh-Taylor instability and the hybrid Rayleigh-Taylor/Kelvin-Helmholtz instability.Moreover,the synergetic mitigation effect is stronger than either of them acting separately.
The inner disc radius in the propeller phase and accretion-propeller transition of neutron stars
Ertan, Ünal
2017-04-01
We have investigated the critical conditions required for a steady propeller effect for magnetized neutron stars with optically thick, geometrically thin accretion discs. We have shown through simple analytical calculations that a steady-state propeller mechanism cannot be sustained at an inner disc radius where the viscous and magnetic stresses are balanced. The radius calculated by equating these stresses is usually found to be close to the conventional Alfvén radius for spherical accretion, rA. Our results show that: (1) a steady propeller phase can be established with a maximum inner disc radius that is at least ∼15 times smaller than rA depending on the mass-flow rate of the disc, rotational period and strength of the magnetic dipole field of the star, (2) the critical accretion rate corresponding to the accretion-propeller transition is orders of magnitude lower than the rate estimated by equating rA to the co-rotation radius. Our results are consistent with the properties of the transitional millisecond pulsars that show transitions between the accretion powered X-ray pulsar and the rotational powered radio-pulsar states.
Bounds of the Spectral Radius and the Nordhaus-Gaddum Type of the Graphs
Tianfei Wang
2013-01-01
Full Text Available The Laplacian spectra are the eigenvalues of Laplacian matrix L(G=D(G-A(G, where D(G and A(G are the diagonal matrix of vertex degrees and the adjacency matrix of a graph G, respectively, and the spectral radius of a graph G is the largest eigenvalue of A(G. The spectra of the graph and corresponding eigenvalues are closely linked to the molecular stability and related chemical properties. In quantum chemistry, spectral radius of a graph is the maximum energy level of molecules. Therefore, good upper bounds for the spectral radius are conducive to evaluate the energy of molecules. In this paper, we first give several sharp upper bounds on the adjacency spectral radius in terms of some invariants of graphs, such as the vertex degree, the average 2-degree, and the number of the triangles. Then, we give some numerical examples which indicate that the results are better than the mentioned upper bounds in some sense. Finally, an upper bound of the Nordhaus-Gaddum type is obtained for the sum of Laplacian spectral radius of a connected graph and its complement. Moreover, some examples are applied to illustrate that our result is valuable.
An accurate mass and radius measurement for an ultracool white dwarf
Parsons, S G; Marsh, T R; Bergeron, P; Copperwheat, C M; Dhillon, V S; Bento, J; Littlefair, S P; Schreiber, M R
2012-01-01
Studies of cool white dwarfs in the solar neighbourhood have placed a limit on the age of the Galactic disk of 8-9 billion years. However, determining their cooling ages requires the knowledge of their effective temperatures, masses, radii, and atmospheric composition. So far, these parameters could only be inferred for a small number of ultracool white dwarfs for which an accurate distance is known, by fitting their spectral energy distributions (SEDs) in conjunction with a theoretical mass-radius relation. However, the mass-radius relation remains largely untested, and the derived cooling ages are hence model-dependent. Here we report direct measurements of the mass and radius of an ultracool white dwarf in the double-lined eclipsing binary SDSS J013851.54-001621.6. We find M(WD)=0.529+/-0.010Msol and R(WD)=0.0131+/-0.0003Rsol. Our measurements are consistent with the mass-radius relation and we determine a robust cooling age of 9.5 billion years for the 3570K white dwarf. We find that the mass and radius o...
Influence of punch radius on elastic modulus of three-point bending tests
Pengliang Hou
2016-05-01
Full Text Available Three-point bending is one of the most common methods of studying the mechanical performance of materials. The influence of punch radius in the measurements is not considered in the previous studies. This article focuses on the influence of the punch radius on the elastic modulus. The experiment is set up to measure the elastic modulus of 6061 aluminum alloy (6061 Al and copper as the specimens, in which several different radii of punches are used. The maximum bending deflection of the middle point is 1.0 mm. Moreover, a finite element simulation is constructed to simulate the bending process of specimen, which is consistent with the experimental results. According to the results, the punch radius has affected the measurement of elastic modulus, and the elastic modulus, the contact length, and the peak load increase with the increase in the punch radius. Combining the experiment result (E1 and the standard result (E3 of Changchun research institute for testing machines, it is found that the appropriate punch radius is in the range from 2.5 to 3.0 mm for this experiment, when the specimen’s dimension is 30.0 mm × 6.0 mm × 1.0 mm.
Weil, Wayne M; Trumble, Thomas E
2005-08-01
The technique of intrafocal pinning was originally described by Kapandji. This technique, along with the addition of supplemental external or internal bridging fixation, can be performed quickly with minimal soft tissue damage. This technique is indicated for the treatment of unstable extra-articular or minimally displaced intra-articular fractures of the distal radius. Studies demonstrate that young patients with displaced extra-articular distal radius fractures and minimal comminution can be treated by percutaneous intrafocal pin fixation alone, whereas, patients over 55 years of age and younger patients with comminution involving two or more surfaces of the radial metaphysis (or > 50% of the metaphyseal diameter) require bridging fixation besides percutaneous pin fixation. The use of this technique achieves the goal of surgical treatment of distal radius fractures: restoration of hand and wrist function through the restoration of alignment and articular surface congruity.
Assessing Upper Tropospheric Jet Streak Proximity Using the Rossby Radius of Deformation
Joshua S. Kastman
2016-12-01
Full Text Available The Rossby radius of deformation is a parameter that describes the relative role of buoyant and inertial forces for atmospheric phenomena in a flow regime. It will be demonstrated that it can also be used to determine whether or not forcing for vertical motions in the region between upper level tropospheric jet streaks overlaps or interacts. Using predefined points in the entrance and exit regions of neighboring upper level jet streaks, the distance between them is calculated for each event. If they are closer than twice the Rossby radius of deformation, the resulting region affected by both streaks is termed the Rossby Radius of Deformation Overlap Zone (RRDOZ. Plan-view and cross-sectional analysis shows that ageostrophic transverse circulations within the RRDOZ led to enhanced upward vertical velocities as predicted in prior research. Lastly, a short-term climatology for overlap events in North America is derived, and these are classified according to three proposed archetypes.
Treatment of distal clavicle fracture with distal radius volar locking compression plate
YU Chao; SUN Yue-hua; ZHAO Chang-qing; SHI Ding-wei; WANG You
2009-01-01
Objective: To observe the early clinical outcomes of the internal fixation with distal radius volar locking compression plate (LCP) in treatment of distal clavicle fracture.Methods: Six patients with unilateral distal clavicle fractures, identified as type Ⅱ according to Neer classification system, including 4 males and 2 females, were treated with open reduction and internal fixation using a distal radius volar LCP. Bone union was evaluated by routine X-ray radiography, and shoulder joint function were assessed by Constant score system.Results: All fractures achieved bone union at 6 to 8 weeks postoperatively, and Constant scores ranged from 95 to 100 at the postoperative 10 to 12 weeks.Conclusion: Fixation of distal clavicle fracture with distal radius volar LCP demonstrates excellent effects of bone union with rarely early complications, thus providing a new technique to treat distal clavicle fracture.
The scalar radius of the pion from lattice QCD in the continuum limit
Guelpers, Vera; Hippel, Georg von [Johannes Gutenberg-Universitaet Mainz, PRISMA Cluster of Excellence and Institut fuer Kernphysik, Mainz (Germany); Wittig, Hartmut [Johannes Gutenberg-Universitaet Mainz, PRISMA Cluster of Excellence and Institut fuer Kernphysik, Mainz (Germany); Johannes Gutenberg-Universitaet Mainz, Helmholtz Institute Mainz, Mainz (Germany)
2015-12-15
We extend our study (Phys. Rev. D 89, 094503 (2014)) of the pion scalar radius in two-flavour lattice QCD to include two additional lattice spacings as well as lighter pion masses, enabling us to perform a combined chiral and continuum extrapolation. We find discretisation artefacts to be small for the radius, and confirm the importance of the disconnected diagrams in reproducing the correct chiral behaviour. Our final result for the scalar radius of the pion at the physical point is left angle r{sup 2} right angle {sub s}{sup π} = 0.600±0.052 fm{sup 2}, corresponding to a value of l{sub 4} = 4.54±0.30 for the low-energy constant l{sub 4} of NLO chiral perturbation theory. (orig.)
Reconstruction of the Distal Radius following Tumour Resection Using an Osteoarticular Allograft
Katharina Rabitsch
2013-01-01
Full Text Available Reconstruction of the distal radius following tumour resection is challenging and various techniques are recorded. We retrospectively analysed the outcome of five patients (one male and four females after reconstruction of the distal radius with osteoarticular allograft, following tumour resection. Mean followup was 32 months (range, 4–121. In three of the five patients the dominant limb was affected. Mean bone resection length was 6.5 centimetres (range, 5–11.5. Two grafts developed nonunion, both successfully treated with autologous bone grafting. No infection, graft fracture, or failure occurred. Mean flexion/extension was 38/60 degrees and mean pronation/supination was 77/77 degrees. The mean Mayo wrist score was 84 and the mean DASH score was 8, both representing a good functional result. Therefore we state the notion that osteoarticular allograft reconstruction of distal radius provides good to excellent functional results.
Calculating the Potato Radius of Asteroids using the Height of Mt. Everest
Caplan, M E
2015-01-01
At approximate radii of 200-300 km, asteroids transition from oblong `potato' shapes to spheres. This limit is known as the Potato Radius, and has been proposed as a classification for separating asteroids from dwarf planets. The Potato Radius can be calculated from first principles based on the elastic properties and gravity of the asteroid. Similarly, the tallest mountain that a planet can support is also known to be based on the elastic properties and gravity. In this work, a simple novel method of calculating the Potato Radius is presented using what is known about the maximum height of mountains and Newtonian gravity for a spherical body. This method does not assume any knowledge beyond high school level mechanics, and may be appropriate for students interested in applications of physics to astronomy.
Sanjeev Kumar Kare
2016-12-01
Full Text Available BACKGROUND Fracture of the distal radius (‘broken wrist’ is a common clinical problem. It can be treated conservatively usually involving wrist immobilisation in a plaster cast or surgically. A key method of surgical fixation is external fixation. MATERIALS AND METHODS A prospective study was carried out on 66 patients admitted between June 2014 to May 2016 for evaluation of conservative and surgical management of distal radius fractures. RESULTS Excellent, fair or good result was noticed in around 85% of cases managed conservatively and in above 90% of cases managed by external fixator. CONCLUSION There is some evidence to support the use of external fixation for dorsally displaced fractures of the distal radius in adults. Though, there is insufficient evidence to confirm a better functional outcome, external fixation reduces redisplacement gives improved anatomical results and most of the excess surgically-related complications are minor.
Nagasawa, Fumiya; Takagi, Jun; Kunihashi, Yoji; Kohda, Makoto; Nitta, Junsaku
2012-02-01
A geometric phase of electron spin is studied in arrays of InAlAs/InGaAs two-dimensional electron gas rings. By increasing the radius of the rings, the time-reversal symmetric Aharonov-Casher oscillations of the electrical resistance are shifted towards weaker spin-orbit interaction regions with their shortened period. We conclude that the shift is due to a modulation of the spin geometric phase, the maximum modulation of which is approximately 1.5 rad. We further show that the Aharonov-Casher oscillations in various radius arrays collapse onto a universal curve if the radius and the strength of Rashba spin-orbit interaction are taken into account. The result is interpreted as the observation of the effective spin-dependent flux through a ring.
The influence of finite Larmor radius effects on the radial interchange motions of plasma filaments
Madsen, Jens; Garcia, Odd E.; Larsen, Jeppe Stærk
2011-01-01
The influence of finite Larmor radius (FLR) effects on the perpendicular convection of isolated particle density filaments driven by interchange motions in magnetized plasmas is investigated using a two-moment gyrofluid model. By means of numerical simulations on a two-dimensional, bi-periodic do......The influence of finite Larmor radius (FLR) effects on the perpendicular convection of isolated particle density filaments driven by interchange motions in magnetized plasmas is investigated using a two-moment gyrofluid model. By means of numerical simulations on a two-dimensional, bi....... Due to FLR effects, the poloidal up-down symmetry in the particle density field observed in the zero Larmor radius limit is broken. The symmetry breaking implies a poloidal motion of the blobs in the BrB direction. At later times, the direction of the poloidal motion is reversed when the blob...
The occultation of Mariner 10 by Mercury. [planetary radius and atmospheric radio measurements
Fjeldbo, G.; Kliore, A.; Sweetnam, D.; Esposito, P.; Seidel, B.; Howard, T.
1976-01-01
Analysis of Mariner 10 dual-frequency radio-occultation recordings has yielded new information on the radius and atmosphere of Mercury. The ingress measurements, which were conducted near 1.1 deg north latitude and 67.4 deg east longitude on the night side of the planet, gave a value for the radius of 2439.5 + or - 1 km. Egress near 67.6 deg north latitude and 258.4 deg east longitude on the sunlit side yielded a radius of 2439.0 + or - 1 km. The atmospheric measurements showed the electron density to be less than 1000 per cu cm on both sides of the planet. From the latter result one may infer an upper limit to the dayside surface gas density of 1 million molecules per cu cm.
Effects of Spot Size on Neutron-Star Radius Measurements from Pulse Profiles
Bauböck, Michi; Psaltis, Dimitrios; Özel, Feryal
2015-10-01
We calculate the effects of spot size on pulse profiles of moderately rotating neutron stars. Specifically, we quantify the bias introduced in radius measurements from the common assumption that spots are infinitesimally small. We find that this assumption is reasonable for spots smaller than 10°-18° and leads to errors that are ≤10% in the radius measurement, depending on the location of the spot and the inclination of the observer. We consider the implications of our results for neutron star radius measurements with the upcoming and planned X-ray missions NICER and LOFT. We calculate the expected spot size for different classes of sources and investigate the circumstances under which the assumption of a small spot is justified.
Effects of Spot Size on Neutron-Star Radius Measurements from Pulse Profiles
Baubock, Michi; Ozel, Feryal
2015-01-01
We calculate the effects of spot size on pulse profiles of moderately rotating neutron stars. Specifically, we quantify the bias introduced in radius measurements from the common assumption that spots are infinitesimally small. We find that this assumption is reasonable for spots smaller than 10-18$^\\circ$ and leads to errors that are $\\le$10% in the radius measurement, depending on the location of the spot and the inclination of the observer. We consider the implications of our results for neutron star radius measurements with the upcoming and planned X-ray missions NICER and LOFT. We calculate the expected spot size for different classes of sources and investigate the circumstances under which the assumption of a small spot is justified.
Sharp bounds on the critical stability radius for relativistic charged spheres: I
Andreasson, Hakan
2007-01-01
In a recent paper by Giuliani and Rothman \\cite{GR}, the problem of finding a lower bound on the radius R of a charged sphere with mass M and charge Q is addressed. Such a bound is referred to as the critical stability radius. Equivalently, it can be formulated as the problem of finding an upper bound on M for given radius and charge. This problem has resulted in a number of papers in recent years but neither a transparent nor a general inequality similar to the case without charge, i.e., $M\\leq 4R/9,$ has been found. In this paper we derive the surprisingly transparent inequality \\begin{equation}\
Sharp bounds on the critical stability radius for relativistic charged spheres
Andreasson, Hakan
2008-01-01
In a recent paper by Giuliani and Rothman \\cite{GR}, the problem of finding a lower bound on the radius $R$ of a charged sphere with mass M and charge Q
Surface Tension of Methanol as a Function of cut-off Radius and Temperature Controllers
Obeidat, Abdalla; Jaradat, Adnan; Hamdan, Bushra
Molecular dynamics is used to calculate the surface tension of van Leeuwen methanol. The van Leeuwen model of methanol is chosen over other models of methanol, since this model is widely used to study nucleation at low temperature. Usually, scientists use the cut-off radius to be three order of magnitude of segment diameter. In this study, we varied the cut-off radius to estimate the best cut-off at which the surface tension reaches its plateau. After deciding the best cut-off radius for van der Waals and Coulomb interactions (CUT-OFF and PME were used for Coulomb interaction), we varied the temperature controller (van-Housen, Berendsen, and v-rescale) to decide the best temperature controller to be used to study methanol. In all simulations, Gromacs is used at T =200-300K with periodic boundary conditions in all dimensions. JUST.
Siegall, Evan; Ziran, Bruce
2014-08-01
A patient with a 1-month-old intra-articular distal radius fracture (treated closed in a splint) presented with an unacceptable degree of pain and stiffness caused by shortening and dorsal angulation of the distal radius. The fracture was comminuted with 4 or 5 distinct fragments, several involving the articular surface. Surgical correction was attempted. During the procedure, it was noted that, though the distal radius was shortened and angulated, there was actually acceptable congruity of the articular surface itself, despite the intra-articular nature of the fracture. Bone quality was poor and healing incomplete. Thus, we were concerned the currently congruous articular surface would fall apart with manipulation. Given this situation, we used a unique scaffolding technique with Kirschner wires placed in perpendicular fashion to both hold the articular surface intact and manipulate it en bloc. This technique is a simple way to turn a complex fracture into an easily reduced 2-part fracture.
Fatemi, Fredrik K; Solano, Pablo; Fenton, Eliot F; Beadie, Guy; Rolston, Steven L; Orozco, Luis A
2016-01-01
Optical nanofibers (ONF) of subwavelength dimensions confine light in modes with a strong evanescent field that can trap, probe, and manipulate nearby quantum systems. To measure the evanescent field and propagating modes, and to optimize ONF performance, a surface probe is desirable during fabrication. We demonstrate a nondestructive measurement of light propagation in ONFs by sampling the local evanescent field with a microfiber. This approach reveals the behavior of all propagating modes, and because the modal beat lengths in cylindrical waveguides depend strongly on radius, simultaneously provides exquisite sensitivity to the ONF radius. We show that our measured spatial frequencies provide a map of the average ONF radius (over a 600 micrometer window) along the 10 mm ONF waist with 40 picometer resolution and high signal-to-noise ratio. The measurements agree with scanning electron microscopy (SEM) to within SEM instrument resolution. This fast method is immune to polarization, intrinsic birefringence, m...
Efficiency Enhancement in a Tapered Free Electron Laser by Varying the Electron Beam Radius
Jiao, Yi; Wu, J.; Cai, Y.; Chao, A.W.; Fawley, W.M.; Frisch, J.; Huang, Z.; Nuhn, H.-D.; /SLAC; Pellegrini, C.; /SLAC /UCLA; Reiche, S.; /PSI, Villigen
2012-02-15
Energy extraction efficiency of a free electron laser (FEL) can be increased when the undulator is tapered after the FEL saturation. By use of ray equation approximation to combine the one-dimensional FEL theory and optical guiding approach, an explicit physical model is built to provide insight to the mechanism of the electron-radiation coherent interaction with variable undulator parameters as well as electron beam radius. The contribution of variation in electron beam radius and related transverse effects are studied based on the presented model and numerical simulation. Taking a recent studied terawatt, 120 m long tapered FEL as an example, we demonstrate that a reasonably varied, instead of a constant, electron beam radius along the undulator helps to improve the optical guiding and thus the radiation output.
Reconstruction of lower end of radius using vascularized upper end of fibula
Koul Ashok
2007-01-01
Full Text Available Background: Giant cell tumor is a fairly common locally invasive tumor in young adults. The lower end of the radius is the second commonest site for this tumor. The most common treatment for this tumor is curettage with or without bone grafting but it carries a significant rate of recurrence. Excision is the treatment of choice, especially for cases in which the cortex has been breached. After excision of the distal end of the radius, different procedures have been described to reconstruct the defect of distal radius. These include partial arthrodesis and hemiarthroplasty using the upper end of the fibula. The upper end of the fibula has a morphological resemblance to the lower end of the radius and has been used to replace the latter. Traditionally it was used as a ′free′ (non-vascularized graft. More recently the upper end of the fibula has been transferred as a vascularized transfer for the same purpose. Though vascularized transfer should be expected to be more physiological, its superiority over the technically simpler non-vascularized transfer has not been conclusively proven. Materials and Methods: Two patients are presented who had giant cell tumor of distal radius. They underwent wide local excision and reconstruction with free vascularized upper end of the fibula. Result: Follow-up period was two and a half years and 12 months respectively. Both patients have returned to routine work. One patient has excellent functional result and the other has a good result. Conclusion: Vascularized upper end of fibula transfer is a reliable method of reconstruction for loss of the distal end of the radius that restores local anatomy and physiology.
Clinical and ultrasonographic evidence of a proximal positional fault of the radius. A case report.
Malo-Urriés, Miguel; Hidalgo-García, César; Bueno-Gracia, Elena; Estébanez-de-Miguel, Elena; Lucha-López, Orosia; Tricás-Moreno, José Miguel
2014-06-01
Positional faults are considered a possible underlying mechanism mimicking the symptoms of a joint sprain. Despite numerous clinical studies indicating the presence of positional faults, there is limited evidence of imaging studies confirming positional faults. This case report is a preliminary study that offers clinical and ultrasonographic evidence of a proximal positional fault of the radius, treated successfully with manual therapy techniques. Three weeks after a bike fall on the outstretched hand, the patient in this study presented with right wrist pain and a lack of progress with conventional conservative treatment (NSAIDs, rest and immobilization). Clinical findings indicating a proximal positional fault of the radius included pain during active pronation increased by associating a passive movement of the radius in a proximal direction and it was reduced by associating a passive movement of the radius in a distal direction. Ultrasonographic (US) images showed a reduction of radio-capitellar distance on the right side (11.4 mm) compared to the left side (13.3 mm). A positive response with a distal mobilization of the radius supported the proximal positional fault of the radius. After two manual therapy sessions, the patient had recovered normal asymptomatic function. The outcomes used to assess function and pain were active pronation range of motion, the Spanish version of the DASH questionnaire and a 0-10 numeric pain rating scale. Each measure was conducted prior and after each treatment session and one week post treatment. The patient was re-examined at 6 months follow-up, during which US images, demonstrated a normalization of the right radio-capitellar distance.
4 mm cannulatedcancellous screws fixation in extra articular distal 1/3 radius fracture - A study
M.S. Patil
2017-01-01
Full Text Available Background: Distal radius fracture are extremely common and represents 16% of fractures treated by orthopaedic surgeons. Near anatomical reduction with restoration of radial length, radial tilt and ulnar variances are important for good functional results. Cannulated 4 mm long threaded using minimally invasive osteosynthesis technique are less aggressive towards soft tissue covering. It allows immediate range of motion of the wrist while maintaining alignment resulting in rapid and comfortable functional recovery. The objective of this study was to evaluate the clinical, radiological and functional efficacy of 4 mm cannulated screws in the management of extra articular distal radius fracture using the criteria of Gartland and Werley point system. Material & Method: 40 Patients with extra articular distal radius fracture were treated by minimally invasive osteosynthesis technique using 4 mm cannulatedcancellous screws in AL-Ameen Medical College Hospital, Bijapur between Nov 2013 to Oct 2015 which included 19 males and 21 female patients. The duration of follow-up was ranged from 12-18 months. Results: Using Demerit scoring system of Gartland and Werley, we had 45% excellent, 50% good, 0% fair and 5% poor results. As per our results, excellent to good results were found in 95% of patients. Conclusion: Cannulatedcancellous screws fixation is an effective means of fixation in distal 1/3 radius fracture, allowing immediate range of motion of the wrist, resulting in a rapid and comfortable functional recovery while maintaining alignment and bone healing. It has higher degree of purchase when treating extra articular distal radius fracture with poor bone quality. Being minimally invasive with minimal soft tissue dissection, less operative time, cost effective, cannulated screws is a good option for both young and elderly patients with extra articular distal radius fracture.
Preferential distal radius fracture in right-handed individuals presenting to an ED.
Pesola, Gene R; Feinberg, Gary A; Ahsan, Habibul
2003-11-01
The purpose of this study was to determine whether there is a lateralizing predisposition toward injury in right hand-dominant (RHD) individuals. The distal radius fracture was used as the injury for evaluation because it is easily defined and can be objectively documented by roentgenography. A prospective case-series design was used to include consecutive RHD patients with a distal radius fracture. There were 86 women with an average age of 63.1 +/- 17.9 years and 41 men with an average age of 44.0 +/- 17.6 years with a significant difference between ages (P <.01). Overall, there were 50 right and 77 left distal radius fractures, which was significantly different than a 50:50 split (P <.025). Stratification and logistic regression analysis revealed that age (dichotomized into age greater than 57 or other) and not gender was a significant factor in the determination of left versus right distal radius fracture. No interaction between age and gender was found. After adjustment for gender, the odds of developing a left compared with right distal radius fracture was 2.3-fold greater for the older compared with the younger age group (95% confidence interval, 1.0-5.2). Preliminary evidence suggests a lateralizing predisposition for left distal radius fractures in older compared with younger individuals who are RHD. If this data holds up, finding the etiology/mechanism of this predisposition might help in designing environments to minimize the impact of this injury pattern in the slightly older individual.
On the pi pi continuum in the nucleon form factors and the proton radius puzzle
Hoferichter, M; de Elvira, J Ruiz; Hammer, H -W; Meißner, U -G
2016-01-01
We present an improved determination of the $\\pi\\pi$ continuum contribution to the isovector spectral functions of the nucleon electromagnetic form factors. Our analysis includes the most up-to-date results for the $\\pi\\pi\\to\\bar N N$ partial waves extracted from Roy-Steiner equations, consistent input for the pion vector form factor, and a thorough discussion of isospin-violating effects and uncertainty estimates. As an application, we consider the $\\pi\\pi$ contribution to the isovector electric and magnetic radii by means of sum rules, which, in combination with the accurately known neutron electric radius, are found to slightly prefer a small proton charge radius.
Brief review of the theory of the muonic hydrogen Lamb shift and the proton radius
Pineda, Antonio
2011-01-01
Recently the muonic hydrogen lamb shift has been measured with unprecedented accuracy, allowing for a precise determination of the proton radius. This determination is 5 sigma away from the previous CODATA value obtained from (mainly) the hydrogen lamb shift and the electron-proton scattering. Within an effective field theory formalism, I will define the proton radius and briefly review some aspects of the theoretical prediction for the muonic hydrogen lamb shift, studying both the pure QED-like computation and the hadronic effects.
Florid Reactive Periostitis of the Ulna and Radius: A Case Report
Lee, Kwang Jin; Kim, Yong Hoon; Hwang, Yoon Joon; Kim, Su Young; Lee, Byeong Hoon; Lee, Ji Young; Kim, You Sung [Dept. of Radiology, Ilsan Paik Hospital, Inje University College of Medicine, Koyang (Korea, Republic of)
2012-04-15
Florid reactive periostitis is a benign periosteal reaction that rarely occurs in the long bones of the forearm. A 43-year-old woman presented with a case of florid reactive periostitis, which affects the distal ulna and radius. Computed tomography and plain radiography showed smooth, uniformed periosteal reaction along the interosseous margins of the distal ulna and radius, without underlying bony cortical erosion or destruction. Magnetic resonance imaging also revealed diffuse edema and enhancement in the subperiosteal area and the adjacent soft tissues.
A Non-Interfering Beam Radius Diagnostic Suitable For Induction Linacs
Nexsen, W E
2005-06-07
High current electron induction linacs operate in a parameter regime that allows the use of a diamagnetic loop (DML) to measure the beam magnetic moment. Under certain easily met conditions the beam radius can be derived from the moment measurement. The DML has the advantage over the present methods of measuring beam radius in that it is an electrical measurement with good time resolution that does not interfere with the beam transport. I describe experiments on the LLNL accelerators, ETA-II and FXR that give confidence in the use of a DML as a beam diagnostic.
Mulders, Marjolein A M; Walenkamp, Monique M J; Goslings, J Carel; Schep, Niels W L
2016-02-09
Of all distal radius fractures, 25 % are complete articular fractures (AO/OTA type C fractures). Two thirds of those fractures are displaced and require reduction. According to several International Guidelines, adequately reduced intra-articular distal radius fractures are best treated non-operatively with plaster immobilisation, while surgical fixation is suggested only when the articular step exceeds 2 mm after reduction. However, these recommendations are based on studies that did not differentiate between intra- and extra-articular distal radius fractures. Thus, no clear consensus about the best treatment for patients with displaced intra-articular distal radius fractures can be reached. Despite the lack of evidence, an increase in internal fixation of intra-articular distal radius fractures has been observed over the last decade. The aim of this study is to determine the difference in functional outcome following open reduction and plate fixation compared with non-operative treatment with closed reduction and plaster immobilisation in patients with a displaced intra articular distal radius fracture. This multicentre randomised controlled trial will randomise between open reduction and internal plate fixation (intervention group) and closed reduction and plaster immobilisation (control group). All consecutive adult patients from 18 to 65 years with a displaced intra-articular distal radius fracture (AO/OTA type C), which has been adequately reduced at the Emergency Department according to the Dutch National Guidelines, are eligible for inclusion in this study. The primary outcome is function and pain of the wrist assessed with the Patient-Rated Wrist Evaluation score (PRWE). Secondary outcomes are the Disability of the Arm, Shoulder and Hand score (DASH), pain, quality of life (SF-36), range of motion, grip strength, radiological parameters, complications, crossovers and cost-effectiveness of both treatments. A total of 90 patients will be included in this
An examination of proton charge radius extractions from e-p scattering data
Arrington, John
2015-01-01
A detailed examination of issues associated with proton radius extractions from elastic electron-proton scattering experiments is presented. Sources of systematic uncertainty and model dependence in the extractions are discussed, with an emphasis on how these may impact the proton charge and magnetic radii. A comparison of recent Mainz data to previous world data is presented, highlighting the difference in treatment of systematic uncertainties as well as tension between different data sets. We find several issues that suggest that larger uncertainties than previously quoted may be appropriate, but do not find any corrections which would resolve the proton radius puzzle.
Transverse radius dependence for transverse velocity and elliptic flow in intermediate energy HIC
YAN Ting-Zhi; LI Shan
2011-01-01
The mean transverse velocity and elliptic flow of light fragments (A≤2) as a function of transverse radius are studied for 25 MeV/nucleon Cu+Cu collisions with impact parameters 3-5 fm by the isospin- dependent quantum molecular dynamics model. By comparison between the in-plane and the out-of-plane transverse velocities, the elliptic flow dependence on the transverse radius can be understood qualitatively, and variation of the direction of the resultant force on the fragments can be investigated qualitatively.
Fine-Tuning on the Effective Patch Radius Expression of the Circular Microstrip Patch Antennas
A. E. Yilmaz
2010-09-01
Full Text Available In this study, the effective patch radius expression for the circular microstrip antennas is improved by means of several manipulations. Departing from previously proposed equations in the literature, one of the most accurate equations is picked up, and this equation is fine-tuned by means of Particle Swarm Optimization technique. Throughout the study, impacts of other parameters (such as the definition of the fitness/objective function, the degree-of-freedom in the proposed effective patch radius expression, the number of measured resonant frequency values are observed in a controlled manner. Finally, about 3% additional improvement is achieved over a very accurate formula, which was proposed earlier.
严方军 ; 梅顺良
2007-01-01
本文在分析RADIUS协议原理基础上,给出了一种基于规则的RADIUS Server的设计方案和实现策略,规则的引入可以很方便在规则配置中定义认证流程和属性逻辑运算,能够在不修改源代码的情况下,高效支持新的设备和新的业务。本RADIUS Server实现已经在实际项目中得到验证。
Should muffin tin radius vary in different structures of a material?: A case study
Nayak, Vikas; Banger, Suman; Verma, U. P.
2014-04-01
Quantum mechanical calculations based on density functional theory and a generalized gradient approximation (GGA) have been used to study the structural properties of YbN. Its predicted unit cell lattice parameter in NaCl (B1) structure is 4.7810Å and in CsCl (B2) structure it is 2.8685Å. In the determination of lattice parameter the muffin tin radius (RMT) of constituent atoms play important role. In both the structures the muffin tin radius for Yb and N converges to 2.3 and 1.4 a.u., respectively.
An Indentation Method for Nanoprecision Measurement of Diamond Tool Edge Radius
X; P; Li; M; Rahman; K; Liu; K; S; Neo; C; C; Chan
2002-01-01
In ductile mode cutting of brittle materials using di amond tools, such as ductile cutting of silicon and quartz for wafer fabrication , one of the key conditions for achieving ductile chip formation is to get the r ight ratio of tool cutting edge radius to the undeformed chip thickness. It has been shown that the undeformed chip thickness has to be in the order of nanomete rs and that the tool cutting edge radius has to be smaller than the undeformed c hip thickness. Therefore, nanoprecision measurement ...
On the ππ continuum in the nucleon form factors and the proton radius puzzle
Hoferichter, M.; Kubis, B.; Ruiz de Elvira, J.; Hammer, H.-W.; Meißner, U.-G.
2016-11-01
We present an improved determination of the ππ continuum contribution to the isovector spectral functions of the nucleon electromagnetic form factors. Our analysis includes the most up-to-date results for the ππ→bar{N} N partial waves extracted from Roy-Steiner equations, consistent input for the pion vector form factor, and a thorough discussion of isospin-violating effects and uncertainty estimates. As an application, we consider the ππ contribution to the isovector electric and magnetic radii by means of sum rules, which, in combination with the accurately known neutron electric radius, are found to slightly prefer a small proton charge radius.
Influence of punch radius on elastic modulus of three-point bending tests
Pengliang Hou; Hongwei Zhao; Zhichao Ma; Shizhong Zhang; Jianping Li; Xiaolong Dong; Yujiao Sun; Zhongwei Zhu
2016-01-01
Three-point bending is one of the most common methods of studying the mechanical performance of materials. The influence of punch radius in the measurements is not considered in the previous studies. This article focuses on the influence of the punch radius on the elastic modulus. The experiment is set up to measure the elastic modulus of 6061 aluminum alloy (6061 Al) and copper as the specimens, in which several different radii of punches are used. The maximum bending deflection of the middl...
Should muffin tin radius vary in different structures of a material?: A case study
Nayak, Vikas, E-mail: vikas.nayak88@gmail.com; Banger, Suman, E-mail: vikas.nayak88@gmail.com; Verma, U. P., E-mail: vikas.nayak88@gmail.com [School of Studies in Physics, Jiwaji University, Gwalior - 474011 (India)
2014-04-24
Quantum mechanical calculations based on density functional theory and a generalized gradient approximation (GGA) have been used to study the structural properties of YbN. Its predicted unit cell lattice parameter in NaCl (B1) structure is 4.7810Å and in CsCl (B2) structure it is 2.8685Å. In the determination of lattice parameter the muffin tin radius (R{sub MT}) of constituent atoms play important role. In both the structures the muffin tin radius for Yb and N converges to 2.3 and 1.4 a.u., respectively.
Multiple topological phase transitions in a gyromagnetic photonic crystal
Chen, Zeguo
2017-04-19
We present the design of a tunable two-dimensional photonic crystal that exhibits multiple topological phases, including a conventional insulator phase, a quantum spin Hall phase, and a quantum anomalous Hall phase under different combinations of geometric parameters and external magnetic fields. Our photonic crystal enables a platform to study the topology evolution attributed to the interplay between crystalline symmetry and time-reversal symmetry. A four-band tight-binding model unambiguously reveals that the topological property is associated with the pseudospin orientations and that it is characterized by the spin Chern number. The emerging quantum anomalous Hall phase features a single helical edge state that is locked by a specific pseudospin. Simulation results demonstrate that the propagation of such a single helical edge state is robust against magnetic impurities. Potential applications, such as spin splitters, are described.
New Experiments to Measure the Muon Anomalous Gyromagnetic Moment
Eads, M
2015-01-01
The magnetic moment is a fundamental property of particles. The measurement of these magnetic moments and the comparison with the values predicted by the standard model of particle physics is a way to test our understanding of the fundamental building blocks of our world. In some cases, such as for the electron, this comparison has resulted in confirmation of the standard model with incredible precision. In contrast, the magnetic moment of the muon has shown a long-standing disagreement in the measured and the predicted value. There is currently a tantalizing three-standard-deviation difference between the current best measurement (with a precision of 0.54 ppm) and the state-of-the-art standard model prediction. This represents one of the very few experimental hints for physics beyond the standard model. There are currently two major experimental efforts underway to improve the precision of the muon magnetic moment measurement. The first is an evolution of the E-821 experiment, originally located at Brookhave...
The proton gyromagnetic g-factor: an electromagnetic model
Sardin, G
2009-01-01
So far, the Standard Model of Elementary Particles has not succeeded getting a trustworthy account of the proton spin, which remains an enigma. This hindrance is known as the proton spin crisis, owing to the experimental evidence already from 1988 suggesting that little or none of the proton spin would come from the spin of the quarks. This prompted theorists to a flood of guessworks about the proton spin. Since it remains unsolved, in the framework of new physics an exploratory approach based on a novel paradigm is proposed, which brings a renewed access to this challenge, through its reciprocal relationship with the g-factor.
THE STEWARTSON LAYER OF A ROTATING-DISK OF FINITE RADIUS
1992-01-01
It is shown that if a disk of finite radius and the surrounding medium rotate coaxially with slightly different angular velocities, an axial layer in the form of a cylindrical shell exists at the edge of the disk. This shell of thickness O(E1/3) has length O(E-1) in axial direction, where E is the E
On the Inner Radius Evolution with Fluxes of the Neutron Star Binary Serpens X-1
Chiang, Chia-Ying; Cackett, Edward M; Miller, Jon M; Bhattacharyya, Sudip; Strohmayer, Tod E
2016-01-01
We analyze the latest Suzaku observation of the bright neutron star system Serpens X-1 taken in 2013 October and 2014 April. The observation was taken using the burst mode and only suffered mild pile-up effects. A broad iron line is detected in the X-ray spectrum. We test different models and find that the iron line is asymmetric and best interpreted by relativistic reflection. The relativistically broadened iron line is generally believed to originate from the innermost regions of the accretion disk, where strong gravity causes a series of special and general relativistic effects. The iron line profile indicates an inner radius of ~8 $R_{\\rm G}$. The asymmetric iron line has been observed in a number of previous observations, which gives several inner radius measurements at different flux states. We find the inner radius to be consistent over a wide range of luminosity, implying that the inner radius of Serpens X-1 does not evolve significantly over the range of $L/L_{\\rm Edd}$ ~ 0.2-0.6.
New and improved hydraulic radius for channels of the second kind
Ali R. Vatankhah
2015-09-01
In current research a new and improved definition of hydraulic radius for closed conduits flowing partially full, is presented. This definition is efficient enough and provides powerful tool to determine the channel discharge and friction slope of uniform flow via Manning’s equation.
Remodeling of Salter-Harris type II epiphyseal plate injury of the distal radius.
Houshian, Shirzad; Holst, Anette Koch; Larsen, Morten S; Torfing, Trine
2004-01-01
The authors studied the relation between residual angulation at the time of healing and final orientation of the distal radius as well as the clinical outcome in patients after Salter-Harris type II epiphyseal plate injury of the distal radius. Eighty-five patients were reviewed with a median follow-up of 8.5 years. Anteroposterior and lateral radiographs were taken at follow-up. The mobility of both wrists and forearms was examined, together with grip strength. Pain with activities and sports was evaluated. At follow-up, 73 patients (86%) were anatomically normal on radiographs; the remaining 12 patients had an incomplete remodeling of the volar and/or radial inclination of the distal radius. Premature closure of the growth plate in the distal radius or ulna did not occur in any of these children. Complete remodeling was seen in children aged up to 10 years in all but one patient. Remodeling after Salter-Harris type II epiphyseal plate injury occurs in all age groups, but the potential is greater in children up to 10 years of age. The incomplete remodeling does not seem to have any substantial long-term negative effect on mobility of the wrist and grip strength.
Classification of distal radius physeal fractures not included in the salter-harris system.
Sferopoulos, Nikolaos K
2014-01-01
The most commonly used classification for pediatric physeal fractures has been proposed by Salter and Harris. Among the most suitable classification schemes are those proposed by Ogden and Peterson who added several new types of injuries. The purpose of this study was to examine the value of both schemes to classify all different types of physeal injuries of the distal radius that are not included in the Salter-Harris system and to test a new nomenclature to classify and guide treatment for the whole spectrum of these injuries. A total of 292 children who were admitted for a physeal fracture of the distal radius that could not be classified according to the Salter-Harris system were identified from the hospital database. All radiographs were carefully examined and classified according to the existing classifications of Ogden and Peterson and a modified classification scheme. The results of the treatment were also evaluated. Ninety-six physeal injuries could not be classified using the classification schemes of Ogden and Peterson. All injuries could be classified in five types using the new, modified nomenclature. Growth abnormalities of the distal radius were evaluated after an average follow-up time of 11 years. Growth arrest due to a physeal bar was detected only in one patient. The proposed modified scheme is practical, incorporates all previous classification systems, allows classification of all physeal injuries of the distal radius that are not included in the Salter-Harris system and may assist comparison of treatment outcomes.
Taylor–Couette turbulence at radius ratio η=0.5: scaling, flow structures and plumes
Veen, van der R.C.A.; Huisman, S.G.; Merbold, S.; Harlander, U.; Egbers, C.; Lohse, D.; Sun, C.
2016-01-01
Using high-resolution particle image velocimetry, we measure velocity profiles, the wind Reynolds number and characteristics of turbulent plumes in Taylor–Couette flow for a radius ratio of 0.5 and Taylor number of up to 6:2 109. The extracted angular velocity profiles follow a log law more closely
RADIUS: Research Archive on Disability in the United States. [CD-ROMs].
Sociometrics Corp., Los Altos, CA.
This Research Archive on Disability in the United States (RADIUS), a database on CD-ROM, contains 19 data sets on the prevalence, incidence, correlates, and consequences of disability in the United States. The 19 data sets are: (1) 1991 National Maternal and Infant Health Follow-Up Survey; (2) National Pediatric Trauma Registry, 1988-1994; (3)…
Turnaround radius in an accelerated universe with quasi-local mass
Faraoni, Valerio; Prain, Angus
2015-01-01
We apply the Hawking-Hayward quasi-local energy construct to obtain in a rigorous way the turnaround radius of cosmic structures in General Relativity. A splitting of this quasi-local mass into local and cosmological parts describes the interplay between local attraction and cosmological expansion.
An ecological hydraulic radius approach to estimate the instream ecological water requirement
LIU Changming; MEN Baohui
2007-01-01
This essay defines the concepts of ecological flow velocity as well as ecological hydraulic radius (EHR) and proposes an ecological hydraulic radius approach (EHRA) which considers both the watercourse information (including hydraulic radius, roughness coefficient and hydraulic gradient) and the required stream velocity necessary for maintenance of certain ecological functions all together. The key parameter of EHRA is to fix the watercourse cross-sectional flow area corresponding to EHR, by which the relation between parabola shaped cross-sectional flow area and hydraulic radius is deduced. The EHRA not only meets the requirement of flow velocity for adequate fish spawning migration, but also is applicable to the ecological flows in regard with other ecological issues (such as the calculation of the instream flow requirements for transporting sediment and for pollution self-purification, etc. ). This essay has illuminated the computational process taking the estimation of ecological water requirement of Zhuba Hydrologyical Station watercourse in Niqu branch of the Yalong River as an example. Additionally, we compare EHRA with Tennant approach. The result shows that the Zhuba Hydrological Station ecological water requirement calculated by EHRA lies between the minimum and favorable ecological water requirement calculated by the Tennant approach. This is due to the fact that the ecological flow velocity (such as the fish spawning migration flow velocity) was taken into consideration, producing results applicable to the practical situation.
Large-radius Holstein polaron and the problem of spontaneous symmetry breaking
Lakhno, V.D.
2014-01-01
A translation-invariant solution is found for a large-radius Holstein polaron whose energy in the strong coupling limit is lower than that obtained by Holstein. The wave function corresponding to this solution is delocalized. A conclusion is made about the absence of a spontaneous symmetry breaking in the quantum system discussed.
Influence of radius of cylinder HTS bulk on guidance force in a maglev vehicle system
Longcai, Zhang
2014-07-01
Bulk superconductors had great potential for various engineering applications, especially in a high-temperature superconducting (HTS) maglev vehicle system. In such a system, the HTS bulks were always exposed to AC external magnetic field, which was generated by the inhomogeneous surface magnetic field of the NdFeB guideway. In our previous work, it was observed that the guidance force of the YBCO bulk over the NdFeB guideway used in the HTS maglev vehicle system was decayed by the application of the AC external magnetic field. In this paper, we investigated the influence of the radius of the cylinder HTS bulk exposed to an AC magnetic field perturbation on the guidance force in the maglev vehicle system. From the results, it was found that the guidance force was stronger for the bulk with bigger radius and the guidance force decay rates of the bulks were approximately equal despite of the different radius in the maglev vehicle system. Therefore, in order to obtain higher guidance force in the maglev vehicle system, we could use the cylinder HTS bulks with the bigger radius.
Progress and prediction of occupational performance in women with distal radius fractures
Nielsen, Tove Lise; Dekkers, Merete Klindt
2013-01-01
To describe the occupational performance and pain during the first year after a distal radius fracture, an observational follow-up study was performed among 37 mainly elderly Danish women. They were assessed at cast removal and reassessed at three and 12 months post-injury with COPM, DASH...
Angular Momentum-Radius Entanglement for an Electron in a Uniform Magnetic Field
范洪义
2002-01-01
Noticing that the angular momentum operator Lz commutes with the square of radius operator, R2, of the orbit track of an electron in a uniform magnetic field, we reveal that a new entanglement is inherent to the common eigenvector of the operators Lz and R2.
Effects of Odanacatib on the Radius and Tibia of Postmenopausal Women
Cheung, Am; Majumdar, S; Brixen, K
2014-01-01
age 64.0 ± 6.8 years, and baseline lumbar spine T-score -1.81 ± 0.83) were randomized to oral ODN 50 mg or PBO weekly for 2 years. With ODN, significant increases from baseline in total vBMD occurred at the distal radius and tibia. Treatment differences from placebo were also significant (3.84% and 2.......63% for radius and tibia, respectively). At both sites, significant differences from placebo were also seen in trabecular vBMD, cortical vBMD, cortical thickness, cortical area and strength (failure load) estimated using finite element analysis of HR-pQCT scans (treatment differences at radius and tibia = 2.......64% and 2.66%). At the distal radius, odanacatib significantly improved trabecular thickness and BV/TV versus placebo. At a more proximal radial site, odanacatib attenuated the increase in cortical porosity seen with placebo (treatment difference= -7.7%, p = 0.066). At the distal tibia, odanacatib...
Measuring the Radius of the Earth from a Mountain Top Overlooking the Ocean
Gangadharan, Dhevan
2009-01-01
A clear view of the ocean may be used to measure the radius of the Earth. To an observer looking out at the ocean, the horizon will always form some angle [theta] with the local horizontal plane. As the observer's elevation "h" increases, so does the angle [theta]. From measurements of the elevation "h" and the angle [theta],…
Characteristics of distal radius speed of sound data in Chinese mainland men and women.
Huang, Ligang; Pan, Jiafei; Jin, Hongting; Xiao, Luwei; Tao, Jing; Tong, Peijian
2015-01-01
Quantitative ultrasound (QUS) assessment of bone health status, as a reliable method, is rapidly gaining popularity. Speed of sound (SOS) is one parameter of skeletal status provided by QUS assessment. The objective of the present study was first to determine the normative distal radius SOS data on healthy Chinese mainland men and women and second to investigate the effects of sex, age, and body size on this parameter. A study cohort consisting of 19,980 healthy Chinese women and 8722 men aged 20-89 yr participated in this investigation. They answered a detailed questionnaire on their healthy condition, and their anthropometric measurements were taken. Their distal radius SOS values were evaluated using the Sunlight ultrasound systems. The distal radius SOS values exhibited a characteristic rise-then-fall pattern with increasing age in both sexes. The peak SOS value occurred at the age of 40-49 both in males and females. Age-related differences were both pronounced among males and females. Pearson correlation and regression analysis showed that age was a major determinant of SOS in both sexes. In females, SOS values had a much stronger correlation with age than male subjects. Body weight was also correlated with SOS but not as well as age. The SOS values of distal radius at present study may be used as normal reference data for Chinese mainland population and will be useful for comparing the results of individual studies and determining diagnostic criteria of osteoporosis by QUS.
Understanding the proton radius puzzle: Nuclear structure effects in light muonic atoms
Ji, Chen; Dinur, Nir Nevo; Bacca, Sonia; Barnea, Nir
2015-01-01
We present calculations of nuclear structure effects to the Lamb shift in light muonic atoms. We adopt a modern ab-initio approach by combining state-of-the-art nuclear potentials with the hyperspherical harmonics method. Our calculations are instrumental to the determination of nuclear charge radii in the Lamb shift measurements, which will shed light on the proton radius puzzle.
Improved precision on the radius of the nearby super-Earth 55 Cnc e
Gillon, M; Benneke, B; Valencia, D; Deming, D; Seager, S; Lovis, C; Mayor, M; Pepe, F; Queloz, D; Segransan, Damien; Udry, S
2011-01-01
We report on new transit photometry for the super-Earth 55 Cnc e obtained with Warm Spitzer/IRAC at 4.5 microns. An individual analysis of these new data leads to a planet radius of 2.21-0.16+0.15 Rearth, in good agreement with the values previously derived from the MOST and Spitzer transit discovery data. A global analysis of both Spitzer transit time-series improves the precision on the radius of the planet at 4.5 microns to 2.20+-0.12 Rearth. We also performed an independent analysis of the MOST data, paying particular attention to the influence of the systematic effects of instrumental origin on the derived parameters and errors by including them in a global model instead of performing a preliminary detrending-filtering processing. We deduce from this reanalysis of MOST data an optical planet radius of 2.04+-0.15 Rearth that is consistent with our Spitzer infrared radius. Assuming the achromaticity of the transit depth, we performed a global analysis combining Spitzer and MOST data that results in a plane...
Self-gravitation of massive charge and the Einstein-Maxwell electron radius
Dekker, H
2014-01-01
The existence of stable, charged elementary 'point particles' still is a basically unsolved puzzle in theoretical physics. E.g., in quantum electrodynamics the infinite self-energy of the Dirac point electron is 'swept under the carpet' by renormalizing its mass. The present work takes a fresh look at the problem by including gravity - without resorting to string theory. Using Einstein's equations for the gravitational fields in a general static isotropic metric with the full energy-momentum tensor (for the charged material mass and the electromagnetic fields) as the source term, an exact solution with a well-defined characteristic radius emerges where mass and charge accumulate: $r_{\\rm c}{=}\\sqrt{r_{\\rm e}r_o/2}$ - with $r_{\\rm e}{=}e^2\\!/4\\pi\\epsilon_omc^2{\\approx}10^{-15}$m being the{~}'classical' electron radius and where $r_o{=}2mG/c^2{\\approx}10^{-57}$m is the Schwarzschild radius belonging to the observable mass $m{\\approx}10^{-30}$kg. The novel 'Einstein-Maxwell' gravitational electron radius can als...
Research methodology in distal radius fracture care : 1 step backward, 2 steps forward
Kleinlugtenbelt, Y.V.
2017-01-01
The clinical practice guideline for distal radius fractures (DRF) has 29 recommendations; however, none of these recommendations were given a “strong” rating owing to limited strength of the evidence. Therefore, determining effective evidence-based treatment of patients with DRFs is crucial. To
Modelling the cutting edge radius size effect for force prediction in micro milling
Bissacco, Giuliano; Hansen, Hans Nørgaard; Jan, Slunsky
2008-01-01
This paper presents a theoretical model for cutting force prediction in micro milling, taking into account the cutting edge radius size effect, the tool run out and the deviation of the chip flow angle from the inclination angle. A parameterization according to the uncut chip thickness to cutting...
Energetically optimal nonstationary mode of flow along tube with constant and time-varying radius
Sergey G. Chefranov
2016-11-01
Full Text Available Derived is a new modification of hydrodynamic equations of viscous incompressible fluid flowing along the tube with radius changing in time. Obtained are exact non-stationary solutions of these equations generalizing a well-known classic stationary solution for Hagen–Poiseuille flow in the tube with radius constant in time. It is demonstrated that the law of changing the tube radius in time may be determined basing on the condition of minimality of the work expended for flowing the set fluid volume along such a tube during the period of radius change cycle. Obtained is the solution of the corresponding variational (isoperimetric problem on conditional extremum determining the limits to dimensionless quantity of the cycle duration set by the specified dimensionless value of the flowed fluid volume. Identified is the generalization of well-known model of optimal branching pipeline (F.L. Chernous’ko, 1977 in which the Poiseuille law modification is used for a new exact non-stationary solution of hydrodynamic equation instead of the law itself. It is demonstrated that the energetically favorable non-stationary modes with negative hydraulic resistance are permissible in certain conditions. The obtained conclusions may be used for development of the hydrodynamic basis of modelling the energy-optimal blood flow realized in the cardiovascular system in norm.
FUNCTIONAL OUTCOME OF UNSTABLE DISTAL RADIUS FRACTURES - TREATED BY PERCUTANEOUS K-WIRE FIXATION
Chatla
2015-10-01
Full Text Available BACKGROUND: Distal radius fractures are very common and increasing in incidence, especially in older age group. There are various methods of treatment available each one has its own merits and demerits. Our technique involves closed reduction, percutaneous K-wire fixation, and POP immobilzation of the unstable distal radius fracture for 4-6 weeks. This study aims to examine the functional outcome of percutaneous pinning of these unstable distal radius fractures. MATERIAL AND METHODS: This is a prospective study of 48 patients aged between 35years to 74years, with unstable distal radius fracture. Patients were treated by closed reduction, percutaneous pinning using two to three k-wires. The wires are cut and bent to the outside. A posterior below elbow POP slab was applied for 4-6 weeks. All the patients were fallowed up at regular intervals of 3weeks, 6 weeks, 12 weeks and 24 weeks. The functional evaluation was done at 24 weeks follow-up. We used Sarmiento’s modification of Lindstrom criteria and Gartland & Warley’s criteria for evaluation of results. RESULTS: Excellent to good results were seen in 91.66% of cases, fair results in 8.34%. CONCLUSION: Percutaneous pinning is a simple, functionally effective, safe method to maintain the fracture reduction and prevent stiffness of wrist and hand.
Scale factor correction for Gaussian beam truncation in second moment beam radius measurements
Hofer, Lucas R.; Dragone, Rocco V.; MacGregor, Andrew D.
2017-04-01
Charged-couple devices (CCD) and complementary metal oxide semiconductor (CMOS) image sensors, in conjunction with the second moment radius analysis method, are effective tools for determining the radius of a laser beam. However, the second moment method heavily weights sensor noise, which must be dealt with using a thresholding algorithm and a software aperture. While these noise reduction methods lower the random error due to noise, they simultaneously generate systematic error by truncating the Gaussian beam's edges. A scale factor that is invariant to beam ellipticity and corrects for the truncation of the Gaussian beam due to thresholding and the software aperture has been derived. In particular, simulations showed an order of magnitude reduction in measured beam radius error when using the scale factor-irrespective of beam ellipticity-and further testing with real beam data demonstrated that radii corrected by the scale factor are independent of the noise reduction parameters. Thus, through use of the scale factor, the accuracy of beam radius measurements made with a CCD or CMOS sensor and the second moment are significantly improved.
A Spitzer Infrared Radius for the Transiting Extrasolar Planet HD 209458 b
Richardson, L. Jeremy; Harrington, Joseph; Seager, Sara; Deming, Drake
2007-01-01
We have measured the infrared transit of the extrasolar planet HD 209458 b using the Spitzer Space Telescope. We observed two primary eclipse events (one partial and one complete transit) using the 24 micrometer array of the Multiband Imaging Photometer for Spitzer (MIPS). We analyzed a total of 2392 individual images (10-second integrations) of the planetary system, recorded before, during, and after transit. We perform optimal photometry on the images and use the local zodiacal light as a short-term flux reference. At this long wavelength, the transit curve has a simple box-like shape, allowing robust solutions for the stellar and planetary radii independent of stellar limb darkening, which is negligible at 24 micrometers. We derive a stellar radius of R(sub *) = 1.06 plus or minus 0.07 solar radius, a planetary radius of R(sub p) = 1.26 plus or minus 0.08 R(sub J), and a stellar mass of 1.17 solar mass. Within the errors, our results agree with the measurements at visible wavelengths. The 24 micrometer radius of the planet therefore does not differ significantly compared to the visible result. We point out the potential for deriving extrasolar transiting planet radii to high accuracy using transit photometry at slightly shorter IR wavelengths where greater photometric precision is possible.
Yang, Wuming
2016-01-01
The determination of the size of the convective core of main-sequence stars is usually dependent on the construction of models of stars. Here we introduce a method to estimate the radius of the convective core of main-sequence stars with masses between about 1.1 and 1.5 $M_{\\odot}$ from observed frequencies of low-degree p-modes. A formula is proposed to achieve the estimation. The values of the radius of the convective core of four known stars are successfully estimated by the formula. The radius of the convective core of KIC 9812850 estimated by the formula is $\\mathbf{0.140\\pm0.028}$ $R_{\\odot}$. In order to confirm this prediction, a grid of evolutionary models were computed. The value of the convective-core radius of the best-fit model of KIC 9812850 is $0.149$ $R_{\\odot}$, which is in good agreement with that estimated by the formula from observed frequencies. The formula aids in understanding the interior structure of stars directly from observed frequencies. The understanding is not dependent on the c...
Team physician #5. Salter-Harris type I fracture of the distal radius due to weightlifting.
Weiss, A P; Sponseller, P D
1989-02-01
A Salter-Harris Type I distal radius fracture was sustained by a skeletally immature adolescent while performing a supine bench press during weight training. Closed reduction was accomplished without difficulty. Fractures in adolescence due to weightlifting are rare but illustrate the need for proper instruction and supervision.
Predictions of Crystal Structure Based on Radius Ratio: How Reliable Are They?
Nathan, Lawrence C.
1985-01-01
Discussion of crystalline solids in undergraduate curricula often includes the use of radius ratio rules as a method for predicting which type of crystal structure is likely to be adopted by a given ionic compound. Examines this topic, establishing more definitive guidelines for the use and reliability of the rules. (JN)
Pole-strength of the earth from Magsat and magnetic determination of the core radius
Voorhies, G. V.; Benton, E. R.
1982-01-01
A model based on two days of Magsat data is used to numerically evaluate the unsigned magnetic flux linking the earth's surface, and a comparison of the 16.054 GWb value calculated with values from earlier geomagnetic field models reveals a smooth, monotonic, and recently-accelerating decrease in the earth's pole strength at a 50-year average rate of 8.3 MWb, or 0.052%/year. Hide's (1978) magnetic technique for determining the radius of the earth's electrically-conducting core is tested by (1) extrapolating main field models for 1960 and 1965 downward through the nearly-insulating mantle, and then separately comparing them to equivalent, extrapolated models of Magsat data. The two unsigned fluxes are found to equal the Magsat values at a radius which is within 2% of the core radius; and (2) the 1960 main field and secular variation and acceleration coefficients are used to derive models of 1930, 1940 and 1950. The same core magnetic radius value, within 2% of the seismic value, is obtained. It is concluded that the mantle is a nearly-perfect insulator, while the core is a perfect conductor, on the decade time scale.
Effective transverse radius of nucleon in high-energy elastic diffractive scattering
Godizov, A.A. [NRC ' ' Kurchatov Institute' ' , Institute for High Energy Physics, Protvino (Russian Federation)
2015-05-15
High-energy elastic diffraction of nucleons is considered in the framework of the simplest Regge-eikonal approximation. It is demonstrated explicitly that the effective transverse radius of nucleon in this nonperturbative regime is ∝ 0.2 / 0.3 fm and much less than the transverse size of the diffractive interaction region. (orig.)
Kinematics and early migration in single-radius mobile- and fixed-bearing total knee prostheses
Wolterbeek, N.; Garling, E.H.; Mertens, B.J.; Nelissen, R.G.H.H.; Valstar, E.R.
2012-01-01
Background The mobile-bearing variant of a single-radius design is assumed to provide more freedom of motion compared to the fixed-bearing variant because the insert does not restrict the natural movements of the femoral component. This would reduce the contact stresses and wear which in turn may ha
Surgical approach for elastic stable intramedullary nail in pediatric radius shaft fracture
Nørgaard, Sandra L.; Schødt Riber, Sara; Danielsson, Frederik B.
2017-01-01
When using elastic stable intramedullary nailing in children’s distal radius shaft fractures, the surgical approach can either be lateral or dorsal. The aim of this article was to carry out a systematic review of the literature comparing the two types of approaches in terms of complications...
Bounds on the tau and muon neutrino vector and axial vector charge radius
Hirsch, M; Restrepo, D A; Hirsch, Martin; Nardi, Enrico; Restrepo, Diego
2003-01-01
A Majorana neutrino is characterized by just one flavor diagonal electromagnetic form factor: the anapole moment, that in the static limit corresponds to the axial vector charge radius . Experimental information on this quantity is scarce, especially in the case of the tau neutrino. We present a comprehensive analysis of the available data on the single photon production process $e^+e^- -> \
Understanding the ``Proton Radius Puzzle'': Nuclear Polarizability Correction in μD
Hernandez, Oscar J.; Dinur, Nir Nevo; Ji, Chen; Bacca, Sonia; Barnea, Nir
2016-09-01
The accuracy of the proton radius was improved ten-fold by new spectroscopic measurements in muonic hydrogen but it differs by 7 σ from hydrogen determinations. This discrepancy, has been coined the ``proton radius puzzle''. The results of new high-precision experiments on muonic deuterium indicate a new deuterium radius puzzle. The accuracy of the nuclear charge radius determination from these measurements is limited by the uncertainty in the nuclear structure effects. We have calculated this correction in Ref. including the first estimate of the nuclear-model dependence. Due to the importance of constraining the uncertainty, we will determine the statistical and systematic uncertainties of the χEFT potentials by determining the co-variance matrices of our predictions. I will also discuss an alternate method that may reduce the theoretical uncertainty. TRIUMF receives federal funding via a contribution agreement with the National Research Council of Canada. This work was supported in parts by the Natural Sciences and Engineering Research Council (Grant Number SAPIN-2015-00031).
Friction in metal-on-metal total disc arthroplasty: effect of ball radius.
Moghadas, Parshia; Mahomed, Aziza; Hukins, David W L; Shepherd, Duncan E T
2012-02-02
Total disc arthroplasty (TDA) can be used to replace a degenerated intervertebral disc in the spine. There are different designs of prosthetic discs, but one of the most common is a ball-and-socket combination. Contact between the bearing surfaces can result in high frictional torque, which can then result in wear and implant loosening. This study was designed to determine the effects of ball radius on friction. Generic models of metal-on-metal TDA were manufactured with ball radii of 10, 12, 14 and 16 mm, with a radial clearance of 0.015 mm. A simulator was used to test each sample in flexion-extension, lateral bending and axial rotation at frequencies of 0.25, 0.5, 0.75, 1, 1.25, 1.5, 1.75 and 2 Hz under loads of 50, 600, 1200 and 2000 N, in new born calf serum. Frictional torque was measured and Stribeck curves were plotted to illustrate the lubrication regime in each case. It was observed that implants with a smaller ball radius showed lower friction and showed boundary and mixed lubrication regimes, whereas implants with larger ball radius showed boundary lubrication only. This study suggests designing metal-on-metal TDAs with ball radius of 10 or 12 mm, in order to reduce wear and implant loosening. Copyright © 2011 Elsevier Ltd. All rights reserved.
Martineau, D; Shorez, J; Beran, C; Dass, A G; Atkinson, P
2014-01-01
The ideal treatment strategy for the dorsally comminuted distal radius fracture continues to evolve. Newer plate designs allow for variable axis screw placement while maintaining the advantages of locked technology. The purpose of this study is to compare the biomechanical properties of one variable axis plate with two traditional locked constructs. Simulated fractures were created via a distal 1 cm dorsal wedge osteotomy in radius bone analogs. The analogs were of low stiffness and rigidity to create a worst-case strength condition for the subject radius plates. This fracture-gap model was fixated using one of three different locked volar distal radius plates: a variable axis plate (Stryker VariAx) or fixed axis (DePuy DVR, Smith & Nephew Peri-Loc) designs. The constructs were then tested at physiologic loading levels in axial compression and bending (dorsal and volar) modes. Construct stiffness was assessed by fracture gap motion during the different loading conditions. As a within-study control, intact bone analogs were similarly tested. All plated constructs were significantly less stiff than the intact control bone models in all loading modes (pbending (pbending.
climatic and seasonal variations of effective-earth-radius factor and ...
2008-04-12
Apr 12, 2008 ... Keywords: illicrowave links, effective-earth radius, scale height and line -of-s ight. Introduction. Refractive ... causes bending of a radio ray towards the. Earth, is' normally not ... Table 1 shows the different types of atmospheric ...
Polycarbonate and co-continuous polycarbonate/ABS blends: influence of notch radius
Inberg, J.P.F.; Gaymans, R.J.
2002-01-01
The influence of notch tip radius in the range of 1–0.002 mm was studied on polycarbonate (PC) and co-continuous PC/acrylonitrile–butadiene–styrene (ABS). Co-continuous PC/ABS blend was obtained by mixing PC and ABS containing 15% polybutadiene (PB) in a twin screw extruder. PC and PC/ABS specimens
ACS imaging of star clusters in M 51. I. Identification and radius distribution
Scheepmaker, R. A.; Haas, M. R.; Gieles, M.; Bastian, N.; Larsen, S. S.; Lamers, H. J. G. L. M.
2007-07-01
Context: Size measurements of young star clusters are valuable tools to put constraints on the formation and early dynamical evolution of star clusters. Aims: We use HST/ACS observations of the spiral galaxy M 51 in F435W, F555W and F814W to select a large sample of star clusters with accurate effective radius measurements in an area covering the complete disc of M 51. We present the dataset and study the radius distribution and relations between radius, colour, arm/interarm region, galactocentric distance, mass and age. Methods: We select a sample of 7698 (F435W), 6846 (F555W) and 5024 (F814W) slightly resolved clusters and derive their effective radii (R_eff) by fitting the spatial profiles with analytical models convolved with the point spread function. The radii of 1284 clusters are studied in detail. Results: We find cluster radii between 0.5 and ~10 pc, and one exceptionally large cluster candidate with R_eff = 21.6 pc. The median R_eff is 2.1 pc. We find 70 clusters in our sample which have colours consistent with being old GC candidates and we find 6 new “faint fuzzy” clusters in, or projected onto, the disc of M 51. The radius distribution can not be fitted with a power law similar to the one for star-forming clouds. We find an increase in R_eff with colour as well as a higher fraction of clusters with B-V ⪆ 0.05 in the interarm regions. We find a correlation between R_eff and galactocentric distance (RG) of the form R_eff∝ RG0.12±0.02, which is considerably weaker than the observed correlation for old Milky Way GCs. We find weak relations between cluster luminosity and radius: R_eff∝ L0.15±0.02 for the interarm regions and R_eff∝ L-0.11±0.01 for the spiral arm regions, but we do not observe a correlation between cluster mass and radius. Conclusions: The observed radius distribution indicates that shortly after the formation of the clusters from a fractal gas, the radii of the clusters have changed in a non-uniform way. We find tentative
Resection-reconstruction arthroplasty for giant cell tumor of distal radius
Saikia Kabul
2010-01-01
Full Text Available Background: Giant cell tumor (GCT of the distal radius poses problems for reconstruction after resection. Several reconstructive procedures like vascularized and non-vascularized fibular graft, osteo-articular allograft, ceramic prosthesis and megaprosthesis are in use for substitution of the defect in the distal radius following resection. Most authors advocate wrist arthrodesis following resection of distal radius and non vascularized fibular graft. Here we have analyzed the results of aggressive benign GCTs of the distal radius treated by resection and reconstruction arthroplasty using autogenous non-vascularized fibular graft. Materials and Methods: Twenty-four cases of giant cell tumor of the distal radius (mean age 32 years, mean follow-up 6.6 years treated by en-bloc resection and reconstruction arthroplasty using autogenous non-vascularized ipsilateral fibular graft with a minimum followup of two years have been included in this retrospective study. Nineteen cases were of Campanacci grade III and five were of Grade II recurrence. The mean resected length of the radius was 9.5 (8-12 cm. Routine radiographs and clinical assessments regarding pain, instability, recurrence, hand grip strength and functional status were done at regular intervals and functional results were assessed using (musculoskeletal tumor society MSTS-87 scoring. Results: Early radiological union at host-graft junction was achieved at mean 12.5 weeks, (range 12-14 weeks and solid incorporation with callus formation was observed in mean 29 weeks (range 28-32 weeks in all the cases. Satisfactory range of motion (mean 63%, range 52-78% of the wrist was achieved in 18 cases. Grip strength compared to the contralateral hand was found to be 67% (range 58-74%. Functional results were excellent in six cases (25%, good in 14 cases (58.3% and four (16.7% cases had fair results. Soft tissue recurrence was seen in one patient. The most commonly encountered complication was fibulo
Mercury's radius change estimates revisited using high incidence angle MESSENGER data
Di Achille, G.; Popa, C.; Massironi, M.; Ferrari, S.; Mazzotta Epifani, E.; Zusi, M.; Cremonese, G.; Palumbo, P.
2012-04-01
Estimates of Mercury's radius decrease obtained using the amount of strain recorded by tectonics on the planet range from 0.5 km to 2 km. These latter figures appear too low with respect to the radius contraction (up to 5-6 km) predicted by the most accredited studies based on thermo-mechanical evolution models. For this reason, it has been suggested that there may be hidden strain accommodated by features yet unseen on Mercury. Indeed, as it has been already cautioned by previous studies, the identification of tectonic features on Mercury might be largely biased by the lighting geometry of the used basemaps. This limitation might have affected the results of the extrapolations for estimating the radius change. In this study, we mapped tectonic features at the terminator thus using images acquired at high sun incidence angle (>50°) that represents the optimal condition for their observation. In fact, images with long shadows enhance the topography and texture of the surface and are ideal to detect tectonic structures. This favorable illumination conditions allowed us to infer reliable measurements of spatial distribution (i.e. frequency, orientation, and areal density) of tectonic features which can be used to estimate the average contractional strain and planetary radius decrease. We digitized tectonic structures within a region extending for an area of about 12 million sq. km (~16% of planet's surface). More than 1300 tectonic lineaments were identified and interpreted to be compressional features (i.e. lobate scarps, wrinkle ridges, and high relief ridges) with a total length of more than 12300 km. Assuming that the extensional strain is negligible within the area, the average contractional strain calculated for the survey area is ~0.21-0.28% (~0.24% for θ=30°). This strain, extrapolated to the entire surface, corresponds to a contraction in radius of about 2.5-3.4 km (~2.9 km for θ=30°). Interestingly, the values of contractional strain and radius decrease
Reconstruction of a bony bankart lesion: best fit based on radius of curvature.
Dehaan, Alexander; Munch, Jacqueline; Durkan, Michael; Yoo, Jung; Crawford, Dennis
2013-05-01
The inferior coracoid process has traditionally been considered to be the gold standard for glenoid augmentation after anteroinferior bone loss. Other autograft sites, and more recently, osteochondral allograft sites, have been described as potential donor sources. Potential autograft and osteochondral allograft sites were compared to identify the graft source that would provide the best fit for glenoid augmentation. Controlled laboratory study. Mose circles, a geometric tool found on a standard goniometer, were used to make radius of curvature measurements of 10 anatomic locations in 17 cadaveric specimens. The bony surface of the glenoid, measured from superior to inferior (G-SI) and from anterior to posterior (G-AP), was used as the standard for comparison. Autograft sites were the inferior coracoid, lateral coracoid, and inner table of the iliac crest. Potential osteochondral allograft sites were the radial head, scaphoid fossa of the distal radius (S-DR), lunate fossa of the distal radius (L-DR), medial tibial plateau, and lateral distal tibia. An acceptable match for autograft sites was based on a paired analysis and defined as a radius of curvature within 5 mm of the G-SI or the G-AP of the same cadaveric specimen. Allograft sites were evaluated using an unpaired analysis in which an ideal fit was defined as a radius of curvature of 25 to 30 mm, based on the interquartile range of the G-SI and G-AP. The median (interquartile range) radii of curvature for the G-SI and G-AP were 30 mm (range, 25-30 mm) and 25 mm (range, 25-25 mm), respectively. The inferior coracoid was within 5 mm of the G-SI 59% of the time and the G-AP 94% of the time; no measurements from the lateral coracoid or iliac crest were within the range of the glenoid radius of curvature. Analysis of the allograft sites demonstrated an acceptable fit for 94% of the distal tibia, 68% of the medial tibial plateau, 12% of the S-DR, and 0% of the L-DR and the radial head specimens. An autograft of the
MEASURING THE SOLAR RADIUS FROM SPACE DURING THE 2012 VENUS TRANSIT
Emilio, M. [Observatório Astronômico Departamento de Geociências, Universidade Estadual de Ponta Grossa, Paraná (Brazil); Couvidat, S.; Bush, R. I. [HEPL Solar Physics, Stanford University, Stanford, CA 94305 (United States); Kuhn, J. R.; Scholl, I. F., E-mail: memilio@uepg.br, E-mail: kuhn@ifa.hawaii.edu, E-mail: ifscholl@hawaii.edu, E-mail: couvidat@stanford.edu, E-mail: ribush@solar.stanford.edu [Institute for Astronomy, University of Hawaii, Honolulu, HI 96822 (United States)
2015-01-01
We report in this work the determination of the solar radius from observations by the Helioseismic and Magnetic Imager (HMI) and the Atmospheric Imaging Assembly (AIA) instruments on board the Solar Dynamics Observatory during the 2012 June Venus transit of the Sun. Two different methods were utilized to determine the solar radius using images of Sun taken by the HMI instrument. The first technique fit the measured trajectory of Venus in front of the Sun for seven wavelengths across the Fe I absorption line at 6173 Å. The solar radius determined from this method varies with the measurement wavelength, reflecting the variation in the height of line formation. The second method measured the area of the Sun obscured by Venus to determine the transit duration from which the solar radius was derived. This analysis focused on measurements taken in the continuum wing of the line, and applied a correction for the instrumental point spread function (PSF) of the HMI images. Measurements taken in the continuum wing of the 6173 Å line, resulted in a derived solar radius at 1 AU of 959.''57 ± 0.''02 (695, 946 ± 15 km). The AIA instrument observed the Venus transit at ultraviolet wavelengths. Using the solar disk obscuration technique, similar to that applied to the HMI images, analysis of the AIA data resulted in values of R {sub ☉} = 963.''04 ± 0.''03 at 1600 Å and R {sub ☉} = 961.''76 ± 0.''03 at 1700 Å.
Multivariate injury risk criteria and injury probability scores for fractures to the distal radius.
Burkhart, Timothy A; Andrews, David M; Dunning, Cynthia E
2013-03-15
The purpose of this study was to develop a multivariate distal radius injury risk prediction model that incorporates dynamic loading variables in multiple directions, and interpret the distal radius failure data in order to establish injury probability thresholds. Repeated impacts with increasing intensity were applied to the distal third of eight human cadaveric radius specimens (mean (SD) age=61.9 (9.7)) until injury occurred. Crack (non-propagating damage) and fracture (specimen separated into at least two fragments) injury events were recorded. Best subsets analysis was performed to find the best multivariate injury risk model. Force-only risk models were also determined for comparison. Cumulative distribution functions were developed from the parameters of a Weibull analysis and the forces and risk scores (i.e., values calculated from the injury risk models) from 10% to 90% probability were calculated. According to the adjusted R(2), variance inflation factor and p-values, the model that best predicted the crack event included medial/lateral impulse, Fz load rate, impact velocity and the natural logarithm of Fz (Adj. R(2)=0.698), while the best predictive model of the fracture event included medial/lateral impulse, impact velocity and peak Fz (Adj. R(2)=0.845). The multivariate models predicted injury risk better than both the Fz-only crack (Adj. R(2)=0.551) and fracture (Adj. R(2)=0.293) models. Risk scores of 0.5 and 0.6 corresponded to 10% failure probability for the crack and fracture events, respectively. The inclusion of medial/lateral impulse and impact velocity in both crack and fracture models, and Fz load rate in the crack model, underscores the dynamic nature of these events. This study presents a method capable of developing a set of distal radius fracture prediction models that can be used in the assessment and development of distal radius injury prevention interventions.
Li, Zhaosheng; Falanga, Maurizio; Chen, Li; Qu, Jinlu; Xu, Renxin
2017-08-01
The measurement of neutron star mass and radius is one of the most direct ways to distinguish between various dense matter equations of state. The mass and radius of accreting neutron stars hosted in low-mass X-ray binaries can be constrained by several methods, including photospheric radius expansion from type I X-ray bursts and from quiescent spectra. In this paper, we apply for the first time these two methods simultaneously to constrain the mass and radius of Aql X-1. The quiescent spectra from Chandra and XMM-Newton, and photospheric radius expansion bursts from RXTE are used. The determination of the mass and radius of Aql X-1 is also used to verify the consistency between the two methods and to narrow down the uncertainties of the neutron star mass and radius. It is found that the distance to Aql X-1 should be in the range of 4.0-5.75 kpc, based on the overlapping confidence regions between photospheric radius expansion burst and quiescent spectra methods. In addition, we show that the mass and radius determined for the compact star in Aql X-1 are compatible with strange star equations of state and conventional neutron star models.
Isaac Sunder Sen
2016-10-01
Full Text Available BACKGROUND The aim of the study is to categorically suggest the apt method of surgical technique for a particular type of distal radius fracture (Frykman’s type III-VI. Distal radius fracture are among the most common fractures of the upper extremity inspite of increased focus on regular prevention of osteoporosis, early identification and its prompt management. Most distal radius fractures are the result of low energy mechanisms that can be successfully treated either nonoperatively or with a variety of operative techniques if indicated. Complex distal radius fractures occur most commonly in high-energy injuries with extensive comminution or bone loss and associated soft tissue or vascular injuries. These high-energy fractures can present challenges in reconstructing the distal radius. Effective restoration of the bony architecture requires a thorough knowledge of distal radius anatomy, understanding of the goals of treatment, versatility in surgical approaches and familiarity with multiple fixation options. Although, majority of the extra-articular fracture without signs of instability can be successfully managed with POP immobilisation for a period of 4-5 weeks followed by active physiotherapy, other types (Frykman’s III-VI need surgical management that too with combination of surgical techniques namely augmented spanning external fixator with supplemented K-wire fixation or external fixation followed by fragment specific volar locking compression plate osteosynthesis. MATERIALS AND METHODS I have studied 50 cases of distal radius fractures classified using Frykman’s classification using combination of techniques namely augmented spanning external fixator application with K-wire supplementation and spanning external fixator application followed by volar LCP fixation in which external fixator had been used as a reduction tool in majority of the cases and external fixator had been removed after plate osteosynthesis. In some cases retained
Analysis of the radius and diameter protocols in terms of pricing telecommunication services
Vesna M. Radonjić
2013-06-01
Full Text Available Accounting of telecommunication services is closely related to the functions of authentication and authorization. These functions are usually considered together and implemented within the same server using a common protocol. The most renowned protocols for authentication, authorization and accounting are the RADIUS and Diameter protocols. AAA functions and related protocols In this chapter, the accounting management architecture developed by IETF is presented. It includes the interaction between network elements, accounting servers and billing and charging servers. Accounting data can be used for management, planning and charging users as well as other (specific purposes. Authentication is the process of confirming a user's digital identity, usually through some type of identifiers and related data. Authorization determines whether a particular entity is authorized to perform an activity. Basic Functions of the RADIUS Protocol The RADIUS architecture is based on a client-server model. It uses UDP on the transport layer. Transactions between the client and the server are authenticated, which is achieved by using a common secret key that is never sent through the network. Given the limited resources available to network devices, RADIUS facilitates and centralizes charging end users, provides some protection against active attacks by unauthorized users and it has great support from different network equipment vendors. Although RADIUS is a widely accepted protocol for the mechanisms of authentication, authorization and accounting, it has certain shortcomings that may be caused by the protocol itself or by its poor implementation. Architecture and Operation of the Diameter Protocol Diameter is a scalable protocol designed by the IETF working group in order to eliminate shortcomings and functional limitations of the RADIUS protocol and eventually to replace it in the near future. Most of the basic Diameter mechanisms and its
Mavani, Kinjal J
2016-01-01
Introduction The management of highly comminuted distal radius fractures still remains a major treatment challenge. Articular comminution and compromised bone quality are the culprits. One novel approach is the technique of Internal Distraction Plating which involves “bridging” the fracture with the use of a standard 3.5mm plate applied dorsally in distraction from the radius, proximal to the fracture, to the long finger metacarpal distally, bypassing the comminuted segment. The plate is removed once fracture union has been achieved. Aim The present study was conducted with the aim to evaluate the role of internal dorsal distraction plating as an alternative method in the treatment of fracture distal radius in terms of special indications, technique and outcome. Materials and Methods This study was a prospective longitudinal study on 20 patients (mean age 62 years) treated with internal distraction plating for comminuted distal radius fractures with specific indications. Regular follow-ups with standard radiographs and analysis were done upto 24 months. Functional outcome were assessed by DASH Score and the Gartland and Werley demerit score. Results At final follow-up, all fractures had united and X-rays showed mean palmar tilt of 7°, positive ulnar variance of 0.5mm, radial inclination of 18° and average loss of 2mm of radial height. Mean range of motion values for wrist flexion 46°, extension 50°, pronation 79° and supination 77° At final follow-up, the mean DASH score was 32. 85% patient had excellent to good result as per Gartland and Werley demerit score. This construct has yield satisfactory clinical and radiographic results with these very challenging injuries. Conclusion The purpose of this study was to report the radiographic and the functional outcomes of treatment with this technique. External fixator and volar plating in communited distal end radius fractures are not always satisfactory in old age with osteoporotic bone because of
Gogna Paritosh
2013-12-01
Full Text Available 【Abstract】Objective: Metaphyseal-diaphyseal fractures of the distal radius are a major treatment dilemma and orthopaedic surgeons have to pay due consideration to restoration of anatomy of distal radius together with ro- tation of the radial shaft and maintenance of radial bow and interosseous space. We performed this study to evaluate the clinic-radiological outcome of metaphyseal-diaphyseal fractures of the distal radius treated with long volar locking plates. Methods: This prospective study involved 27 pa- tients (22 males and 5 females with metaphyseal-diaphy- seal fracture of the distal radius. Their mean age was (30.12± 11.48 years (range 19-52 years and the follow-up was 26.8 months (range 22-34 months. All patients underwent open reduction and internal fixation with a long volar locking plate. According to AO/OTA classification, there were 7 type A3, 13 type C2 and 7 type C3 fractures. Subjective assessment was done based on the disabilities of the arm, shoulder and hand (DASH questionnaire. Functional evaluation was done by measuring grip strength and range of motion around the wrist and the radiological determinants included radial angle, radial length, volar angle and ulnar variance. The final as- sessment was done according to Gartland and Werley scor- ing system. Results: Postoperative radiological parameters were well maintained throughout the trial, and there was signifi- cant improvement in the functional parameters from 6 weeks to final follow-up. The average DASH scores improved from 37.5 at 6 weeks to 4.2 at final follow-up. Final assessment using Gartland and Werley scoring system revealed 66.67% (n=18 excellent and 33.33% (n=9 good results. There was one case of superficial infection which responded to antibi- otics and another carpel tunnel syndrome which was ma- naged conservatively. Conclusion: Volar locking plate fixation for metaphy- seal-diaphyseal fractures of distal radius is associated with excellent to good
Incidence and characteristics of distal radius fractures in a southern Swedish region
Atroshi Isam
2007-05-01
Full Text Available Abstract Background The incidence of distal radius fracture has increased substantially during the last 50 years according to several studies that estimated the overall incidence in various general populations. The incidence of fracture classified according to severity has not been well documented. The aim of this population-based study was to estimate the overall and type-specific incidence rates of distal radius fracture in a representative population in southern Sweden. Methods During 2001, all persons older than 18 years with acute distal radius fracture in the southern Swedish region of Northeastern Scania were prospectively recorded. A radiologist classified the fractures according to the AO system and measured volar tilt and ulnar variance. A fracture with volar tilt outside a range of -5° to 20° and/or ulnar variance of 2 mm or greater was defined as displaced. Results 335 persons with acute distal radius fracture were recorded during the 1-year period. The overall incidence rate was 26 (95% confidence interval 23–29 per 10,000 person-years. Among women the incidence rate increased rapidly from the age of 50 and reached a peak of 119 per 10,000 person-years in women 80 years and older. The incidence rate among women 50 to 79 years old (56 per 10,000 person-years was lower than that reported in previous studies of similar populations. Among men the incidence rate was low until the age of 80 years and older when it increased to 28 per 10,000 person-years. Fractures classified as AO type A comprised about 80% of the fractures in women and 64% in men. Almost two-thirds of all fractures were displaced and among men and women 80 years and older more than 80% of the fractures were displaced. Conclusion The incidence rate of distal radius fracture in women 50 to 79 years old was lower than previously reported, which may indicate declining incidence in this group. In both sexes, the incidence was highest in the age group of 80 years and older
Fan Jian; Chen Kai; Zhu Hui; Jiang Bo; Yuan Feng; Zhu Xiaozhong; Mei Jiong
2014-01-01
Background L-shaped incision of pronator quadratus (PQ) muscle along its radial and distal borders was always taken for distal radius fractures reduction and internal fixation.Repair of the PQ muscle was always recommended at the end of operation for some instructive reasons.But repair of PQ is not satisfied because of poor quality of muscle and fascial tissues which may cause pain or impede forearm pronation and supination for post-operative scarring around PQ.Inserting the locking palmar plate to pass under the pronator quadratus muscle and the locking screws are inserted through miniincisions in pronator quadratus in some patients with distal radius fractures is a reasonable technique which can preserve the pronator quadratus.The purpose of this study was to evaluate and compare the clinical effects after volar plating of the distal radius fractures while preserving the pronator quadratus and pronator quadratus repair.Methods Between September 2010 and April 2012,65 patients (42 males and 23 females; aged 20-68 years and a mean age of 42.5 years) with distal radius fracture underwent open reduction and internal fixation using the volar locking palmar plates (Depuy or Smith companies).The patients were classified as 23A-2 through 23C-3 according to the Orthopaedic Trauma Association (OTA) classifications.All surgeries were completed by the same trained team.The volar locking palmar plates of distal radius performed with preserving pronator quadratus group involved 30 patients including 19 males and 11 females and performed with pronator quadratus repair group involved 35 patients including 23 males and 12 females.We compared the two groups for wrist pain,forearm range of motion,grip strength,pedoperative complications and wrist functional recovery score.Results The minimum follow-up for the whole cohort was one year.The differences between the two groups were significant with regard to wrist pain,forearm range of motion,grip strength and wrist function at 1,2,and
In vivo movement of femoral flexion axis of a single-radius total knee arthroplasty.
Shimizu, Norimasa; Tomita, Tetsuya; Yamazaki, Takaharu; Yoshikawa, Hideki; Sugamoto, Kazuomi
2014-12-01
The objective of this study was to investigate in vivo femoro-tibial motion using the movement of femoral flexion axis of a single-radius TKA. We examined 20 clinically successful knees with a single-radius posterior stabilized TKA to evaluate the kinematics of deep knee flexion using 2-3-dimensional registration techniques. The mean knee flexion range of motion was 117.8°. The mean rotation of the femoral component was 7.6° external rotation. The mean knee flexion angle at initial post-cam engagement was 55.2°. No paradoxical movement of femoral component was shown until 70° flexion, afterward the femoral component rolled back with flexion. The data showed that the design of this prosthesis might contribute to reduce the paradoxical anterior femoral movement and provide stability in mid-flexion ranges.
Model independent extraction of the proton magnetic radius from electron scattering
Epstein, Zachary; Paz, Gil; Roy, Joydeep
2014-10-01
We combine constraints from analyticity with experimental electron-proton scattering data to determine the proton magnetic radius without model-dependent assumptions on the shape of the form factor. We also study the impact of including electron-neutron scattering data, and ππ→NN ¯ data. Using representative data sets we find for a cut of Q2≤0.5 GeV2, rMp=0.91-0.06+0.03±0.02 fm using just proton scattering data; rMp=0.87-0.05+0.04±0.01 fm adding neutron data; and rMp=0.87-0.02+0.02 fm adding ππ data. We also extract the neutron magnetic radius from these data sets obtaining rMn=0.89-0.03+0.03 fm from the combined proton, neutron, and ππ data.
The Lamb shift in muonic hydrogen and the proton radius from effective field theories
Peset, Clara; Pineda, Antonio [Universitat Autonoma de Barcelona, Grup de Fisica Teorica, Dept. Fisica and IFAE, Bellaterra (Barcelona) (Spain)
2015-12-15
We comprehensively analyse the theoretical prediction for the Lamb shift in muonic hydrogen, and the associated determination of the proton radius. We use effective field theories. This allows us to relate the proton radius with well-defined objects in quantum field theory, eliminating unnecessary model dependence. The use of effective field theories also helps us to organize the computation so that we can clearly state the parametric accuracy of the result. In this paper we review all (and check several of) the contributions to the energy shift of order α{sup 5}, as well as those that scale like α{sup 6} x logarithms in the context of non-relativistic effective field theories of QED. (orig.)
Slow axis collimation lens with variable curvature radius for semiconductor laser bars
Xiong, Ling-Ling; Cai, Lei; Zheng, Yan-Fang; Liu, Hui; Zhang, Pu; Nie, Zhi-Qiang; Liu, Xing-Sheng
2016-03-01
Based on Snell's law and the constant phase in the front of optical field, a design method of the slow axis collimation lens with variable curvature radius is proposed for semiconductor laser bars. Variable radius of the collimator is designed by the transmission angle, and it is demonstrated that the collimator has good beam collimation ability by material with low refractive index. Resorting to the design thought of finite element method, the surface of the collimator has been divided, and it is feasible to be fabricated. This method is applied as an example in collimation of a 976 nm semiconductor laser bar. 6 mrad divergence angle of collimated beam at slow axis is realized by the designed collimation lens with refraction index of 1.51.
Study on the Radius of an Electrical Spherical Micelle:Functional Theoretical Approach
WANG,Zheng-Wu(王正武); HUANG,Dong-Yang(黄东阳); YI,Xi-Zhang(易希璋); LI,Gan-Zuo(李干佐)
2004-01-01
For the purpose of eliminating restriction,the Poisson-Boltzmann(PB)equation,which represents the potential of the electrical double layer of spherical micelles,can be solved analytically only under the lower potential condition,a kind of iterative method in functional analysis theory has been used.The radius of the spherical particle can be obtained from the diagram of the second iterative solution of the potential versus the distance from the center of the particle.The influences of the concentration of the ions,the charge number of ions,the aggregation number of the particle,the dielectric constant of solvent and the temperature of system on the radius also have been studied.
The primary Sauve-Kapandji procedure--for treatment of comminuted distal radius and ulnar fractures.
Horii, E; Ohmachi, T; Nakamura, R
2005-02-01
We have performed primary Sauve-Kapandji procedures on four patients with severe open comminuted fractures of both the distal radius and ulna. The fragmented distal ulna was fixed to the sigmoid notch in order to stabilize the ulnar side of the carpus, and a proximal pseudoarthrosis was maintained for forearm rotation. All the distal radial fractures united without major complications. The mean wrist flexion/extension arc was 76 degrees , the mean pronation/supination arc was 135 degrees, and grip strength was 64% of the contralateral side. All patients returned to their work or daily activities within short time period without any additional surgical treatment, except for removal of implants in three patients. The primary Sauve-Kapandji procedure is effective for the reconstruction of severely combined distal radius and ulnar fractures.
Cloud liquid water, mean droplet radius, and number density measurements using a Raman lidar
Whiteman, David N. [Laser Remote Sensing Branch, NASA Goddard Space Flight Center, Greenbelt, Maryland (United States); Melfi, S. Harvey [Department of Physics, University of Maryland, Baltimore County, Baltimore (United States)
1999-12-27
A new technique for measuring cloud liquid water, mean droplet radius, and droplet number density is outlined. The technique is based on simultaneously measuring Raman and Mie scattering from cloud liquid droplets using a Raman lidar. Laboratory experiments on liquid microspheres have shown that the intensity of Raman scattering is proportional to the amount of liquid present in the spheres. This fact is used as a constraint on calculated Mie intensity assuming a gamma function particle size distribution. The resulting retrieval technique is shown to give stable solutions with no false minima. It is tested using Raman lidar data where the liquid water signal was seen as an enhancement to the water vapor signal. The general relationship of retrieved average radius and number density is consistent with traditional cloud physics models. Sensitivity to the assumed maximum cloud liquid water amount and the water vapor mixing ratio calibration are tested. Improvements to the technique are suggested. (c) 1999 American Geophysical Union.
Mass-radius relation of low and very low-mass stars revisited with the VLTI
Demory, B -O; Forveille, T; Queloz, D; Beuzit, J -L; Delfosse, X; Di Folco, E; Kervella, P; Bouquin, J -B Le; Perrier, C
2009-01-01
We measured the radii of 7 low and very low-mass stars using long baseline interferometry with the VLTI interferometer and its VINCI and AMBER near-infrared recombiners. We use these new data, together with literature measurements, to examine the luminosity- radius and mass-radius relations for K and M dwarfs. The precision of the new interferometric radii now competes with what can be obtained for double-lined eclipsing binaries. Interferometry provides access to much less active stars, as well as to stars with much better measured distances and luminosities, and therefore complements the information obtained from eclipsing systems. The radii of magnetically quiet late-K to M dwarfs match the predictions of stellar evolution models very well, providing direct confirmation that magnetic activity explains the discrepancy that was recently found for magnetically active eclipsing systems. The radii of the early K dwarfs are well reproduced for a mixing length parameter that approaches the solar value, as qualita...
图的谱半径和Hamilton性%Spectral radius and Hamiltonicity of a graph
朱五华
2011-01-01
从图G的闭包理论角度去研究图的Hamilton性。利用图的补图谱半径的界，讨论了Hamilton图存在的谱条件，证明了n阶图G，如果它的补图的谱半径小于或等于（n-3）的算术平方根，则G是Hamilton图。%The Hamihonicity is studied from the closure theory of a graph G. We discuss some spectral conditions for the existence of Hamilton graph by using bounds of spectral radius of the Complement of a graph, and show that if G is a graph of order n with spectral radius of its complement is less than or equal to the arithmetic square root of （ n - 3） , then G is a Hamilton graph.
Electromagnetic performance analysis of reflector antennas with non-uniform errors along radius
Peiyuan Lian; Congsi Wang; Wei Wang; Binbin Xiang
2016-01-01
Based on the works of Greve and Rahmat-Sami , the electromagnetic (EM) performance of the reflector antenna with non-uniform surface errors along radius is further addressed. A mathematical model is developed to describe the weighting func-tion for the non-uniform surface errors along radius. Then, some discussions on the peak gain loss (PGL) and the first sidelobe level increase (SLLI) caused by the non-uniform surface errors are presented and several significant radiation characteristics of the reflector with non-uniform errors are pointed out. Last, based on the proposed model, the weighted root mean square (RMS) value of the surface errors is produced to evaluate the EM performance and several representative cases with different non-uniform errors are presented with good results. Results show that the weighted RMS value should be taken into account for a better quality evalu-ation of the reflector surface.
The Lamb shift in muonic hydrogen and the proton radius from effective field theories
Peset, Clara
2015-01-01
We comprehensively analyse the theoretical prediction for the Lamb shift in muonic hydrogen, and the associated determination of the proton radius. We use effective field theories. This allows us to relate the proton radius with well-defined objects in quantum field theory, eliminating unnecessary model dependence. The use of effective field theories also helps us to organize the computation so that we can clearly state the parametric accuracy of the result. In this paper we review all (and check several of) the contributions to the energy shift of order $\\alpha^5$, as well as those that scale like $\\alpha^6\\times$logarithms in the context of non-relativistic effective field theories of QED.
Limits on the effective quark radius from inclusive ep scattering at HERA
Abramowicz, H.; Abt, I.; Adamczyk, L.; Adamus, M.; Antonelli, S.; Aushev, V.; Behnke, O.; Behrens, U.; Bertolin, A.; Bhadra, S.; Bloch, I.; Boos, E. G.; Brock, I.; Brook, N. H.; Brugnera, R.; Bruni, A.; Bussey, P. J.; Caldwell, A.; Capua, M.; Catterall, C. D.; Chwastowski, J.; Ciborowski, J.; Ciesielski, R.; Cooper-Sarkar, A. M.; Corradi, M.; Dementiev, R. K.; Devenish, R. C. E.; Dusini, S.; Foster, B.; Gach, G.; Gallo, E.; Garfagnini, A.; Geiser, A.; Gizhko, A.; Gladilin, L. K.; Golubkov, Yu. A.; Grzelak, G.; Guzik, M.; Gwenlan, C.; Hain, W.; Hlushchenko, O.; Hochman, D.; Hori, R.; Ibrahim, Z. A.; Iga, Y.; Ishitsuka, M.; Januschek, F.; Jomhari, N. Z.; Kadenko, I.; Kananov, S.; Karshon, U.; Kaur, P.; Kisielewska, D.; Klanner, R.; Klein, U.; Korzhavina, I. A.; Kotański, A.; Kötz, U.; Kovalchuk, N.; Kowalski, H.; Krupa, B.; Kuprash, O.; Kuze, M.; Levchenko, B. B.; Levy, A.; Limentani, S.; Lisovyi, M.; Lobodzinska, E.; Löhr, B.; Lohrmann, E.; Longhin, A.; Lontkovskyi, D.; Lukina, O. Yu.; Makarenko, I.; Malka, J.; Mastroberardino, A.; Mohamad Idris, F.; Mohammad Nasir, N.; Myronenko, V.; Nagano, K.; Nobe, T.; Nowak, R. J.; Onishchuk, Yu.; Paul, E.; Perlański, W.; Pokrovskiy, N. S.; Polini, A.; Przybycień, M.; Roloff, P.; Ruspa, M.; Saxon, D. H.; Schioppa, M.; Schneekloth, U.; Schörner-Sadenius, T.; Shcheglova, L. M.; Shevchenko, R.; Shkola, O.; Shyrma, Yu.; Singh, I.; Skillicorn, I. O.; Słomiński, W.; Solano, A.; Stanco, L.; Stefaniuk, N.; Stern, A.; Stopa, P.; Sukhonos, D.; Sztuk-Dambietz, J.; Tassi, E.; Tokushuku, K.; Tomaszewska, J.; Tsurugai, T.; Turcato, M.; Turkot, O.; Tymieniecka, T.; Verbytskyi, A.; Wan Abdullah, W. A. T.; Wichmann, K.; Wing, M.; Yamada, S.; Yamazaki, Y.; Zakharchuk, N.; Żarnecki, A. F.; Zawiejski, L.; Zenaiev, O.; Zhautykov, B. O.; Zotkin, D. S.
2016-06-01
The high-precision HERA data allows searches up to TeV scales for beyond the Standard Model contributions to electron-quark scattering. Combined measurements of the inclusive deep inelastic cross sections in neutral and charged current ep scattering corresponding to a luminosity of around 1 fb-1 have been used in this analysis. A new approach to the beyond the Standard Model analysis of the inclusive ep data is presented; simultaneous fits of parton distribution functions together with contributions of "new physics" processes were performed. Results are presented considering a finite radius of quarks within the quark form-factor model. The resulting 95% C.L. upper limit on the effective quark radius is 0.43 ṡ10-16 cm.
Commentary on the Radius of the Sun: Optical Illusion or Manifestation of a Real Surface?
Robitaille P.-M.
2013-04-01
Full Text Available In modern solar theory, the photospheric surface merely act s as an optical illusion. Gases cannot support the existence of such a boundary. Conve rsely, the liquid metallic hydrogen model supports the idea that the Sun has a distinct s urface. Observational as- tronomy continues to report increasingly precise measures of solar radius and diameter. Even the smallest temporal variations in these parameters w ould have profound impli- cations relative to modeling the Sun and understanding clim ate fluctuations on Earth. A review of the literature convincingly demonstrates that th e solar body does indeed pos- sess a measurable radius which provides, along with previou s discussions (Robitaille P.M. On the Presence of a Distinct Solar Surface: A Reply to He rv ́e Faye. Progr. Phys. , 2011, v. 3, 75–78., the twenty-first line of evidence that t he Sun is comprised of condensed-matter.
Cloud Liquid Water, Mean Droplet Radius and Number Density Measurements Using a Raman Lidar
Whiteman, David N.; Melfi, S. Harvey
1999-01-01
A new technique for measuring cloud liquid water, mean droplet radius and droplet number density is outlined. The technique is based on simultaneously measuring Raman and Mie scattering from cloud liquid droplets using a Raman lidar. Laboratory experiments on liquid micro-spheres have shown that the intensity of Raman scattering is proportional to the amount of liquid present in the spheres. This fact is used as a constraint on calculated Mie intensity assuming a gamma function particle size distribution. The resulting retrieval technique is shown to give stable solutions with no false minima. It is tested using Raman lidar data where the liquid water signal was seen as an enhancement to the water vapor signal. The general relationship of retrieved average radius and number density is consistent with traditional cloud physics models. Sensitivity to the assumed maximum cloud liquid water amount and the water vapor mixing ratio calibration are tested. Improvements to the technique are suggested.
Chen, Zhuoying; O'Brien, Stephen
2008-06-01
We report a nanoparticle radius ratio dependent study of the formation of binary nanoparticle superlattices (BNSLs) of CdTe and CdSe quantum dots. While keeping all other parameters identical in the system, the effective nanoparticle radius ratio, gamma(eff), was tuned to allow the formation of five different BNSL structures, AlB(2), cub-NaZn(13), ico-NaZn(13), CaCu(5), and MgZn(2). For each structure, gamma(eff) is located close to a local maximum of its space-filling factor, based on a model for space filling principles. We demonstrate the ability to select specific BNSLs based solely on gamma(eff), highlighting the role of entropic forces as a driver for self-assembly.
Radius of Curvature Measurement of Large Optics Using Interferometry and Laser Tracker
Hagopian, John; Connelly, Joseph
2011-01-01
The determination of radius of curvature (ROC) of optics typically uses either a phase measuring interferometer on an adjustable stage to determine the position of the ROC and the optics surface under test. Alternatively, a spherometer or a profilometer are used for this measurement. The difficulty of this approach is that for large optics, translation of the interferometer or optic under test is problematic because of the distance of translation required and the mass of the optic. Profilometry and spherometry are alternative techniques that can work, but require a profilometer or a measurement of subapertures of the optic. The proposed approach allows a measurement of the optic figure simultaneous with the full aperture radius of curvature.
Lee, Jungpyo; Wright, John; Bertelli, Nicola; Jaeger, Erwin F.; Valeo, Ernest; Harvey, Robert; Bonoli, Paul
2017-05-01
In this paper, a reduced model of quasilinear velocity diffusion by a small Larmor radius approximation is derived to couple the Maxwell's equations and the Fokker Planck equation self-consistently for the ion cyclotron range of frequency waves in a tokamak. The reduced model ensures the important properties of the full model by Kennel-Engelmann diffusion, such as diffusion directions, wave polarizations, and H-theorem. The kinetic energy change ( W ˙ ) is used to derive the reduced model diffusion coefficients for the fundamental damping (n = 1) and the second harmonic damping (n = 2) to the lowest order of the finite Larmor radius expansion. The quasilinear diffusion coefficients are implemented in a coupled code (TORIC-CQL3D) with the equivalent reduced model of the dielectric tensor. We also present the simulations of the ITER minority heating scenario, in which the reduced model is verified within the allowable errors from the full model results.
Mean radius and shape of Pluto and Charon from New Horizons images
Nimmo, Francis; Umurhan, Orkan; Lisse, Carey M.; Bierson, Carver J.; Lauer, Tod R.; Buie, Marc W.; Throop, Henry B.; Kammer, Josh A.; Roberts, James H.; McKinnon, William B.; Zangari, Amanda M.; Moore, Jeffrey M.; Stern, S. Alan; Young, Leslie A.; Weaver, Harold A.; Olkin, Cathy B.; Ennico, Kim
2017-05-01
Approach images taken by the LORRI imaging system during the New Horizons spacecraft encounter have been used to determine the mean radii and shapes of Pluto and Charon. The primary observations are limb locations derived using three independent approaches. The resulting mean radii of Pluto and Charon are 1188.3 ± 1.6 km and 606.0 ± 1.0 km, respectively (2-σ). The corresponding densities are 1854 ± 11 kg/m3 and 1701 ± 33 kg/m3 (2-σ). The Charon radius value is consistent with previous Earth-based occultation estimates. The Pluto radius estimate is consistent with solar occultation measurements performed by the ALICE and Fine Sun Sensor instruments on New Horizons. Neither Pluto nor Charon show any evidence for tidal/rotational distortions; upper bounds on the oblateness are < 0.6% and < 0.5%, respectively.
Tang, Wen Xuan; Zhang, Hao Chi; Liu, Jun Feng; Xu, Jie; Cui, Tie Jun
2017-01-23
Spoof surface plasmon polariton (SPP) has been realized at low frequencies through corrugated metallic structures. As two-dimensional application, the ultrathin SPP transmission lines (TLs) have been proposed with great potentials for microwave compact circuits due to the strong field confinement and enhancement, as well as controllable dispersive properties. In this paper, we examine the radiation loss at small-radius bend, which may cause severe crosstalk in highly-integrated circuits or systems, for the SPP TLs. We theoretically analyze that the SPP TL has essential merit of low radiation loss, and show better performance of SPP TL than the conventional microstrip line through numerical simulations and experiments. Both simulated and measured results demonstrate that the new type of transmission line can efficiently suppress the radiation loss at small-radius bend, and hence reduce the crosstalk in circuits and systems.
Correlating charge radius with quadrupole deformation and $B(E2)$ in atomic nuclei
Sun, Bao-Hua; Wang, Hao-Xin
2016-01-01
A very good linear correlation is found between the four-point charge radius relation $\\delta R_{2p-2n}(Z,N)$ with that of quadrupole deformation data in even-even nuclei. This results in a further improved charge radius relation that holds in a precision of about 5$\\times 10^{-3}$ fm. Such correlations are also seen in global nuclear models, their precisions, however, are not enough to be consistent with the experimental data. The new relation between charge radii and deformation of even-even nuclei can be generalized to the reduced electric quadrupole transition probability $B(E2)$ between the first $2^+$ state and the $0^+$ ground state, and the mean lifetime $\\tau$ of the first 2$^+$ state.
Limits on the effective quark radius from inclusive ep scattering at HERA
Abramowicz, H. [Tel Aviv Univ. (Israel). School of Physics; Max Planck Institute for Physics, Munich (Germany); Abt, I. [Max Planck Institute for Physics, Munich (Germany); Adamczyk, L. [AGH-Univ. of Science and Technology, Krakow (Poland). Faculty of Physics and Applied Computer Sciences; Collaboration: ZEUS Collaboration; and others
2016-04-15
The high-precision HERA data allows searches up to TeV scales for Beyond the Standard Model contributions to electron-quark scattering. Combined measurements of the inclusive deep inelastic cross sections in neutral and charged current ep scattering corresponding to a luminosity of around 1 fb{sup -1} have been used in this analysis. A new approach to the beyond the Standard Model analysis of the inclusive ep data is presented; simultaneous fits of parton distribution functions together with contributions of ''new physics'' processes were performed. Results are presented considering a finite radius of quarks within the quark form-factor model. The resulting 95% C.L. upper limit on the effective quark radius is 0.43.10{sup -16} cm.
Evolution of the spherical cavity radius generated around a subsurface drip emitter
M. Gil
2010-06-01
Full Text Available The emitter discharge in subsurface drip irrigation can be affected by soil properties. A positive pressure develops at the emitter outlet where a spherical cavity is assumed to form. In steady-state conditions, the pressure in the soil relates to soil hydraulic properties, the emitter discharge, and the cavity radius. This pressure in the soil is very sensitive to the cavity radius. In this paper, the development of the cavity around the emitter outlet was measured for various emitter discharges in laboratory tests carried out in containers with uniform loamy soils. A trend between soil pressure and emitter discharge was established that illustrates the performance of buried emitters in the field. Its application to the prediction of water distribution in subsurface drip irrigation units and its effect on the estimation of irrigation performance are also shown.
Mass-radius relations for white dwarf stars of different internal compositions
Panei, J A; Benvenuto, O G
2000-01-01
The purpose of this work is to present accurate and detailed mass-radius relations for white dwarf (WD) models with helium, carbon, oxygen, silicon and iron cores, by using a fully updated stellar evolutionary code. We considered masses from 0.15 to 0.5 Mo for the case of helium core, from 0.45 to 1.2 Mo for carbon, oxygen and silicon cores and from 0.45 to 1.0 Mo for the case of an iron core. In view of recent measurements made by Hipparcos that strongly suggest the existence of WDs with an iron-dominated core, we focus our attention mainly on the finite-temperature, mass-radius relations for WD models with iron interiors. Furthermore, we explore the effects of gravitational, chemical and thermal diffusion on low-mass helium WD models with hydrogen and helium envelopes.
Steffen, Jason H
2015-01-01
Motivated by recent discussions, both in private and in the literature, we use a Monte Carlo simulation of planetary systems to investigate sources of bias in determining the mass-radius distribution of exoplanets for the two primary techniques used to measure planetary masses---Radial Velocities (RVs) and Transit Timing Variations (TTVs). We assert that mass measurements derived from these two methods are comparably reliable---as the physics underlying their respective signals is well understood. Nevertheless, their sensitivity to planet mass varies with the properties of the planets themselves. We find that for a given planet size, the RV method tends to find planets with higher mass while the sensitivity of TTVs is more uniform. This ``sensitivity bias'' implies that a complete census of TTV systems is likely to yield a more robust estimate of the mass-radius distribution provided there are not important physical differences between planets near and far from mean-motion resonance. We discuss differences in...
Multiresolution Rotational Symmetry Detection via Radius-Based Frieze-Expansion
Gang Pan
2016-01-01
Full Text Available Rotational symmetry is important for many applications in computer graphics, vision, and image processing. However, it remains difficult to design an effective algorithm for automatic symmetry recognition. In this paper, we present a rotational symmetry detection algorithm, which is easy to use and can determine both the center and the radius of the rotational symmetry supporting region without human interaction. Our algorithm is derived from frieze-expansions approach and improved through a radius-based expansion idea. Multiresolution pyramid is used to accelerate this detection process. We also discuss a solution to deal with rotational symmetry detection under slight affine transformation. Experimental results show that the method is effective for most nature images with rotational symmetry.
Transmission photometry of WASP-12b: simultaneous measurement of the planetary radius in three bands
Copperwheat, C M; Southworth, J; Bento, J; Marsh, T R; Dhillon, V S; Fortney, J J; Littlefair, S P; Hickman, R
2013-01-01
Transmission spectroscopy has been successfully used from both the ground and in space to characterise the atmospheres of transiting exoplanets. This technique is challenging from the ground because ground-based spectrographs tend not to be designed to be photometrically stable, and effects such as variable slit losses cause significant systematic uncertainties. An alternative approach is to use simultaneous photometric observations in multiple wavebands to determine wavelength dependent transit depth differences. We report an application of this technique to one of the hottest known exoplanets, WASP-12b, using the triple-beam camera ULTRACAM. We obtained simultaneous light curves in Sloan u', and two narrow band filters centered on 4169 and 6010 angstroms, with FWHMs 52 and 118 angstroms respectively. We fit these light curves with a photometric model and determine the planetary radius in the three different bands. Our data show no evidence for a difference in planetary radius over the wavelength range we st...
Peine, R; Rikli, D A; Hoffmann, R; Duda, G; Regazzoni, P
2000-01-01
Three different plating techniques were used on experimentally produced dorsally displaced distal radius fractures in cadavers and were tested in 4-point bending: a AO 3.5-mm T plate (group 1), two 2. 0-mm titanium plates 60 degrees to each other (group 2), and the AO pi plate (group 3). A metaphyseal defect was simulated by a dorsally open wedge osteotomy. The tests show that the 2-mm double-plating technique has superior stiffness and statistically equivalent bending and bone gap to failure compared with the AO 3.5-mm T plate or the pi plate when applied to the unstable distal radius fracture model. (J Hand Surg 2000; 25A:29-33. Copyright 2000 by the American Society for Surgery of the Hand.).
Mittelmeier, W; Braun, C; Schäfer, R
2001-01-01
The goal of this study was to compare Kapandji-K-wiring and established K-wiring techniques of the distal radius fracture for primary stability in a biomechanical model: dorsal K-wiring according to Kapandji using different angles of the K-wire, parallel and diagonal alignment of the K-wires. A new testing system which uses a synthetic material enabled us to carry out the cantilever bending test. By application of a lower load, the Kapandji procedure shows a higher reactive torque and stiffness. A higher reaction force of the other techniques, especially of the parallel wiring, are only observable under high-grade bending stress. Application of the Kapandji procedure with K-wires at a smaller angle to the axis of the radius results in the highest primary stability of the procedures investigated in the essential range of initial deformation.
Tang, Wen Xuan; Zhang, Hao Chi; Liu, Jun Feng; Xu, Jie; Cui, Tie Jun
2017-01-01
Spoof surface plasmon polariton (SPP) has been realized at low frequencies through corrugated metallic structures. As two-dimensional application, the ultrathin SPP transmission lines (TLs) have been proposed with great potentials for microwave compact circuits due to the strong field confinement and enhancement, as well as controllable dispersive properties. In this paper, we examine the radiation loss at small-radius bend, which may cause severe crosstalk in highly-integrated circuits or systems, for the SPP TLs. We theoretically analyze that the SPP TL has essential merit of low radiation loss, and show better performance of SPP TL than the conventional microstrip line through numerical simulations and experiments. Both simulated and measured results demonstrate that the new type of transmission line can efficiently suppress the radiation loss at small-radius bend, and hence reduce the crosstalk in circuits and systems. PMID:28112238
Maazi, N.; Rouag, N.
2002-08-01
A model for grain growth simulation, in the presence of preferential particle distribution, is presented. The model predicts two grain size limits due to second-phase particles. Less than the maximal critical radius the grains will shrink. Greater than the minimal critical radius the grains will grow. Between the two limiting radii no grain growth takes place. These critical radii permit us to introduce the effect of the precipitates directly in the simulation procedure, without their assigning sites in the base matrix. In this case, all sites of the matrix are only occupied by grains. The conditions necessary for the development of secondary recrystallization in textured materials such as Fe-3%Si are, first, the stagnation of normal grain growth, second, the presence of special boundaries around the secondary grains. The grain growth simulation is performed until the grain structure was pinned, i.e. when boundaries become pinned.
Radius graft pedicled on the anterior interosseous artery for recurrent ulnar nonunion.
Andro, C; Richou, J; Schiele, P; Hu, W; Le Nen, D
2011-06-01
Recurrent ulnar nonunion challenges the functional prognosis and raises major problems concerning the best therapeutic strategy to follow. The case of a female patient presenting recurrent nonunion of the ulnar diaphysis despite successive treatments is reported. The radius graft pedicled on the anterior interosseous artery from a retrograde approach obtained bone union in 3 months with no functional sequelae. For the first time, we propose a therapeutic alternative calling on a proximally pedicled anterior interosseous flap. This technique can be performed under locoregional anesthesia and does not sacrifice the main artery of the forearm. However, the size of the graft does not entirely compensate for segmentary bone loss. The radius graft pedicled on the anterior interosseus artery is an inventive technique that can solve the problem of difficult ulna nonunions without the disadvantages of vascularized fibula harvesting.
Limits on the effective quark radius from inclusive $ep$ scattering at HERA
Abramowicz, H; Adamczyk, L; Adamus, M; Antonelli, S; Aushev, V; Behnke, O; Behrens, U; Bertolin, A; Bloch, I; Boos, EG; Brock, I; Brook, NH; Brugnera, R; Bruni, A; Bussey, PJ; Caldwell, A; Capua, M; Catterall, CD; Chwastowski, J; Ciborowski, J; Ciesielski, R; Cooper-Sarkar, AM; Corradi, M; Dementiev, RK; Devenish, RCE; Dusini, S; Foster, B; Gach, G; Gallo, E; Garfagnini, A; Geiser, A; Gizhko, A; Gladilin, LK; Golubkov, Yu A; Grzelak, G; Guzik, M; Hain, W; Hochman, D; Hori, R; Ibrahim, ZA; Iga, Y; Ishitsuka, M; Januschek, F; Jomhari, NZ; Kadenko, I; Kananov, S; Karshon, U; Kaur, P; Kisielewska, D; Klanner, R; Klein, U; Korzhavina, IA; Kotański, A; Kötz, U; Kovalchuk, N; Kowalski, H; Krupa, B; Kuprash, O; Kuze, M; Levchenko, BB; Levy, A; Limentani, S; Lisovyi, M; Lobodzinska, E; Löhr, B; Lohrmann, E; Longhin, A; Lontkovskyi, D; Lukina, OYu; Makarenko, I; Malka, J; Mohamad Idris, F; Mohammad Nasir, N; Myronenko, V; Nagano, K; Nobe, T; Nowak, RJ; Onishchuk, Yu; Paul, E; Perlański, W; Pokrovskiy, NS; Przybycien, M; Roloff, P; Ruspa, M; Saxon, DH; Schioppa, M; Schneekloth, U; Schörner-Sadenius, T; Shcheglova, LM; Shevchenko, R; Shkola, O; Shyrma, Yu; Singh, I; Skillicorn, IO; Słomiński, W; Solano, A; Stanco, L; Stefaniuk, N; Stern, A; Stopa, P; Sztuk-Dambietz, J; Tassi, E; Tokushuku, K; Tomaszewska, J; Tsurugai, T; Turcato, M; Turkot, O; Tymieniecka, T; Verbytskyi, A; Wan Abdullah, WAT; Wichmann, K; Wing, M; Yamada, S; Yamazaki, Y; Zakharchuk, N; Żarnecki, AF; Zawiejski, L; Zenaiev, O; Zhautykov, BO; Zotkin, DS; Bhadra, S; Gwenlan, C; Hlushchenko, O; Polini, A; Mastroberardino, A; Sukhonos, D
2016-01-01
The high-precision HERA data allows searches up to TeV scales for Beyond the Standard Model contributions to electron-quark scattering. Combined measurements of the inclusive deep inelastic cross sections in neutral and charged current $ep$ scattering corresponding to a luminosity of around 1 fb$^{-1}$ have been used in this analysis. A new approach to the beyond the Standard Model analysis of the inclusive $ep$ data is presented; simultaneous fits of parton distribution functions together with contributions of "new physics" processes were performed. Results are presented considering a finite radius of quarks within the quark form-factor model. The resulting 95% C.L. upper limit on the effective quark radius is $0.43\\cdot 10^{-16}$ cm.
Brodie's abscess following percutaneous fixation of distal radius fracture in a child.
Rajakulendran, Karthig; Picardo, Natasha E; El-Daly, Ibraheim; Hussein, Rami
2016-04-01
We report the case of a Brodie's abscess presenting five and a half years following closed reduction and percutaneous pinning of a distal radius fracture. The index surgery was complicated by a pin site infection that was treated successfully with antibiotics. The patient represented with forearm pain years later, and radiological investigations revealed a Brodie's abscess in the distal radius at the site of the previous Kirschner wires. The Brodie's abscess was managed through surgical curettage and antibiotics. Staphylococcus aureus and diphtheroid organisms were cultured from the intraoperative specimens. A Brodie's abscess is a form of localised subacute osteomyelitis, which usually occurs in the metaphysis of long bones and can mimic malignancy. Previous trauma or surgery has been implicated as predisposing factors. We have only identified one previously reported case of Brodie's abscess following percutaneous pinning. Ours is the first reported case in an adolescent. The aim of this paper is to raise awareness of this rare complication and review the current literature.
Vargaonkar Gauresh
2014-07-01
Full Text Available 【Abstract】Objective:The rapid expansion of knowledge regarding the functional anatomy of hand and wrist, increasing functional demands of senior citizens and improved methodologies of achieving and maintaining anatomic restoration of distal radius fractures has generated a renewed interest in addressing these fractures in a more precise manner. The purpose of our study was to evaluate the difference in patients function among those treated by 1 closed reduction and Plaster of Paris cast, 2 distractor application, or 3 open reduction and internal fixation with a volar plate, and to assess the treatment choice for each particular fracture type. Methods: A prospective study was carried out on 60 patients with fractures of the distal end radius. Fractures were classified according to the AO classification into type A (extra-articular, type B (partial articular and type C (complete articular. After initial evaluation patients were taken up for either conservative or operative treatment and were followed up for two years. Results: Anatomical results were evaluated according to the Sarmiento’s modification of Lindstrom Criteria, which showed that excellent results were more frequent with open reduction and internal fixation using the plating technique. Clinical and functional results were evaluated according to the demerit point system of Gartland and Werley with Sarmiento modification, which was revealed to relate with the type of treatment techniques. Conclusion: There is no customized solution for all the fractures of the distal radius. The choice of treatment should be based on the fracture type, the patient’s characteristics, the patient’s demands and the treating surgeon’s experience and preference. Key words: Distal end radius fractures; Volar plate; Radial orthofix
Ulnocarpal stabilization in the management of comminuted fractures distal end radius
Gupta Dinesh; Kumar Gaurav
2009-01-01
Background : Malunion due to progressive radial collapse during healing is a common complication following comminuted fracture distal radius treated by conventional methods. Many treatment modalities have been described with their own merits and demerits. Stabilization of ulnocarpal articulation is an effective method to prevent radial collapse during healing, and hence this study. Materials and Methods : A prospective study of 200 patients of comminuted intraarticular fracture lower end rad...
Influence of stellar variability on the determination of the radius during a transit of an exoplanet
Désert J.-M.; Lecavelier des Etangs A.; Parmentier V.; Sing D.
2011-01-01
Stellar variability can affect the estimate of an exoplanet radius measured during a transit. We developed a transit light curve model which includes stellar spots. It appears that, if spectro-photometric technique is used, spots and faculae have to be considered to conclude on atmospheric detection and characterization. When using a model including spots, characterization of Hot-Jupiter atmosphere around active stars is possible with this technique, provided a signal to noise ratio up to 105...
Kubo, Yuki; Shimazu, Hironori
2010-01-01
We discuss a mechanism for cosmic ray penetration into an interplanetary magnetic flux rope, particularly the effect of the finite Larmor radius and magnetic field irregularities. First, we derive analytical solutions for cosmic ray behavior inside a magnetic flux rope, on the basis of the Newton-Lorentz equation of a particle, to investigate how cosmic rays penetrate magnetic flux ropes under an assumption of there being no scattering by small-scale magnetic field irregularities. Next, we pe...
A RETROSPECTIVE STUDY OF DISTAL RADIUS FRACTURES TREATED BY CONSERVATIVE METHOD
Ch. V. Murali
2015-11-01
Full Text Available : BACKGROUND: Undisplaced and minimally displaced fractures of the distal radius are one of the most common injuries. The conservative management of these fractures with closed manipulative reduction and Plaster of Paris casting and assessment of the functional results and complications is the aim of this study. MATERIALS & METHODS: One hundred cases of distal radius fractures in patients aged above 40 years who attended the orthopaedic OPD at King George Hospital, Visakhapatnam from September 2010 to August 2012 were studied retrospectively for a period of 2 years. Only extra articular distal radius fractures treated by closed manipulation and pop cast immobilization were included in this study. POP cast was removed at 6 weeks and patients were sent for rehabilitation to physiotherapy department. All Patients were functionally assessed at regular intervals for a period of 3 months. RESULTS: Functional evaluation was done based on Demerit point system of Gartland & Werley with Sarmiento et al modification. 12% of the patients had excellent outcome, 39% good results, 41% had fair outcome and 8% poor results. CONCLUSION: Better results were achieved in undisplaced and minimally displaced fractures treated conservatively by closed manipulative reduction and cast immobilization. However as the degree of displacement increases the results obtained were poor. Gross displacement and communition were associated with poor results even though accurate reduction was obtained during manipulation. Hence it may be concluded that conservative management still holds good for undisplaced and minimally displaced fractures, however in fractures of distal radius with significant displacement and comminution especially if the quality of bone is not good, it is difficult to obtain good functional outcome through conservative management alone.
DISCOVERY AND ATMOSPHERIC CHARACTERIZATION OF GIANT PLANET KEPLER-12b: AN INFLATED RADIUS OUTLIER
Fortney, Jonathan J.; Nutzman, Philip [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Demory, Brice-Olivier [Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Desert, Jean-Michel; Buchhave, Lars A.; Charbonneau, David; Fressin, Francois [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Rowe, Jason; Caldwell, Douglas A.; Jenkins, Jon M. [SETI Institute/NASA Ames Research Center, Moffett Field, CA 94035 (United States); Marcy, Geoffrey W.; Isaacson, Howard; Howard, Andrew; Knutson, Heather A. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Ciardi, David [NASA Exoplanet Science Institute, Caltech, MS 100-22, 770 South Wilson Avenue, Pasadena, CA 91125 (United States); Gautier, Thomas N. [Jet Propulsion Laboratory/California Institute of Technology, Pasadena, CA 91109 (United States); Batalha, Natalie M. [Department of Physics and Astronomy, San Jose State University, San Jose, CA 95192 (United States); Bryson, Stephen T.; Howell, Steve B. [NASA Ames Research Center, Moffett Field, CA 94035 (United States); Everett, Mark, E-mail: jfortney@ucolick.org [National Optical Astronomy Observatories, Tucson, AZ 85719 (United States); and others
2011-11-01
We report the discovery of planet Kepler-12b (KOI-20), which at 1.695 {+-} 0.030 R{sub J} is among the handful of planets with super-inflated radii above 1.65 R{sub J}. Orbiting its slightly evolved G0 host with a 4.438 day period, this 0.431 {+-} 0.041 M{sub J} planet is the least irradiated within this largest-planet-radius group, which has important implications for planetary physics. The planet's inflated radius and low mass lead to a very low density of 0.111 {+-} 0.010 g cm{sup -3}. We detect the occultation of the planet at a significance of 3.7{sigma} in the Kepler bandpass. This yields a geometric albedo of 0.14 {+-} 0.04; the planetary flux is due to a combination of scattered light and emitted thermal flux. We use multiple observations with Warm Spitzer to detect the occultation at 7{sigma} and 4{sigma} in the 3.6 and 4.5 {mu}m bandpasses, respectively. The occultation photometry timing is consistent with a circular orbit at e < 0.01 (1{sigma}) and e < 0.09 (3{sigma}). The occultation detections across the three bands favor an atmospheric model with no dayside temperature inversion. The Kepler occultation detection provides significant leverage, but conclusions regarding temperature structure are preliminary, given our ignorance of opacity sources at optical wavelengths in hot Jupiter atmospheres. If Kepler-12b and HD 209458b, which intercept similar incident stellar fluxes, have the same heavy-element masses, the interior energy source needed to explain the large radius of Kepler-12b is three times larger than that of HD 209458b. This may suggest that more than one radius-inflation mechanism is at work for Kepler-12b or that it is less heavy-element rich than other transiting planets.
Long-term evolution of broken wakefields in finite radius plasmas
Lotov, Konstantin; Petrenko, Alexey
2014-01-01
A novel effect of fast heating and charging a finite-radius plasma is discovered in the context of plasma wakefield acceleration. As the plasma wave breaks, the most of its energy is transferred to plasma electrons which create strong charge-separation electric field and azimuthal magnetic field around the plasma. The slowly varying field structure is preserved for hundreds of wakefield periods and contains (together with hot electrons) up to 80% of the initial wakefield energy.
Computing the nucleon Dirac radius directly at $Q^2=0$
Hasan, Nesreen; Green, Jeremy; Krieg, Stefan; Meinel, Stefan; Negele, John; Pochinsky, Andrew; Syritsyn, Sergey
2016-01-01
We describe a lattice approach for directly computing momentum derivatives of nucleon matrix elements using the Rome method, which we apply to obtain the isovector magnetic moment and Dirac radius. We present preliminary results calculated at the physical pion mass using a 2HEX-smeared Wilson-clover action. For removing the effects of excited-state contamination, the calculations were done at three source-sink separations and the summation method was used.
[New minimally invasive approach for palmar plating in distal radius fractures].
Chmielnicki, M; Prokop, A
2015-02-01
Distal radius fractures are among the most common fractures. Types A3 and C2 make up almost half of these. Volar fixed-angle plate fixation is the gold standard of treatment today. We wanted to minimise the approach to the distal radius through a transverse 2-3 cm incision in the wrist flexor fold, tunnelling beneath the pronator muscle. The operative technique is demonstrated here. 11 patients, averaging 70 years of age, underwent surgery for 7 A3 and 4 C2 type fractures. Average operating time was 50 minutes. Length of admission averaged 2.9 days. Using a visual analogue scale, pain decreased from 6/10 preoperatively to 3/10 on post-op day one and 2/10 on post-op day three. After 6 weeks, flexion and extension averaged 45-0-45°, and radial and ulnar deviation 20-0-20°. Pronation and supination averaged 85-0-85°. Grip strength with manometer averaged 90 % compared to the contralateral side at 6 weeks and 96 % at 3 months. As comparison, from 1 January 2008 until 31 May 2013, we treated 908 patients with distal radius fractures with volar fixed-angle plates through a conventional longitudinal incision of 5-8 cm. The average skin to skin time was 46 minutes, with an average length of admission of 5.6 days. A minimally invasive approach to treat distal radius fractures with volar plate fixation and sparing of the pronator muscle is possible. The initial patients treated with this approach experienced minimal post-operative pain, shorter hospital admissions, and rapid grip strength recovery with almost undisturbed rotational motion.
Influences of nuclear containment radius on the aircraft impact force based on the Riera function
Zhang, T.; Wu, H., E-mail: abrahamhao@126.com; Fang, Q.; Gong, Z.M.
2015-11-15
Highlights: • A fine aircraft model of A320 was built and verified by available limited prototype impacting tests. • The influences of aircraft longitudinal crushing strength on the impact process were analyzed. • The influences of NPP containment radius on the impact force were numerically studied. • The Riera function was modified by considering the radius effect of NPP containment. - Abstract: The aircraft impact force directly influences the local failure and global response of the nuclear power plant (NPP) containment, while the existing theoretical models and the field tests were almost based on the flat target. In order to analyze the radius effect of the circular sectional containment on the impact force, a fine FE model of the commercial aircraft A320 was established and validated by the available limited full-scale F-4 Phantom impact experiment. In order to determine the force to crush the A320 FE model, the influences of aircraft longitudinal crushing strength on the impact process were analyzed based on the Riera function. Considering the containment decaying effect to aircraft impact velocity, the impact impulse was theoretically calculated, while the influences of the losses of mass and energy were not included. The numerical simulations of A320 aircrafts impacting on simplified NPP containments with different radii were conducted, which could well reproduce the airframe crushing and debris scattering. By comparison of the simulated impact impulses and the calculation values by the Riera function, the coefficients corresponding to different containment radii are derived and a fitting formula is obtained. Finally, an improved Riera function dependent on the dimensionless ratio of nuclear containment radius and aircraft wingspan is proposed.
Measurements of atomic splittings in atomic hydrogen and the proton charge radius
Hessels, E. A.
2016-09-01
The proton charge radius can be determined from precise measurements of atomic hydrogen spectroscopy. A review of the relevant measurements will be given, including an update on our measurement of the n=2 Lamb shift. The values obtained from hydrogen will be compared to those obtained from muonic hydrogen and from electron-proton elastic scattering measurements. This work is funded by NSERC, CRC and CFI.
Ashok S; Ankit; Aundhakar; Lekha; Umardand
2016-01-01
It is a rare genetic disorder characterized by the absence of the radius bone in the forearm and a dramatically reduced platelet count. This syndrome may occur as a part of the 1q21.1 deletion syndrome. Symptoms of thrombocytopenia or a lowered platelet count leads to bruising and potentially life-threatening haemorrhage. Affected children who survive this period and do not have damaging haemorrhages in the brain usually have a normal life expectancy and normal intellectual develo...
Using a Video Camera to Measure the Radius of the Earth
Carroll, Joshua; Hughes, Stephen
2013-01-01
A simple but accurate method for measuring the Earth's radius using a video camera is described. A video camera was used to capture a shadow rising up the wall of a tall building at sunset. A free program called ImageJ was used to measure the time it took the shadow to rise a known distance up the building. The time, distance and length of…
Bazot, M.; Ireland, M.J.; Huber, D.
2011-01-01
Sco. We observed the star during 12 nights with HARPS for seismology and used the PAVO beam-combiner at CHARA for interferometry. An average large frequency separation 134.4 ± 0.3 μHz and angular and linear radiuses of 0.6759 ± 0.0062 mas and 1.010 ± 0.009 Rsun were estimated. We used these values...
Primary hyperparathyroidism associated with a giant cell tumor: One case in the distal radius.
Ouzaa, M R; Bennis, A; Iken, M; Abouzzahir, A; Boussouga, M; Jaafar, A
2015-10-01
Hyperparathyroidism can present itself as brown tumors (or osteolytic expansive lesions) that usually disappear after normalization of calcium and phosphate levels. It rarely occurs simultaneously with a giant cell tumor. The authors report one case of a localized form at the distal radius in a patient being followed for primary hyperparathyroidism. The diagnostic challenges related to the clinical and radiological similarities of these two pathological entities are discussed, as they can lead to delays in therapeutic management.
Finite Element Analysis for Effect of Roll Radius on Metal Deformation of Hot Rolling Plate
LUO De-xing; CHEN Qi-an; LIU Li-wen
2005-01-01
The deformation of rolling piece in hot rolling by flat roll with different radii is analyzed with three-dimensional large deformation thermo-mechanical coupling finite element method. The distribution laws of stress, strain and strain energy density in deformation zone with rolls of different radii were studied. The result indicated that under the same condition, the larger the roll radius is, the more vigorous the deformation in deformation zone is.
Material Removal Model Considering Influence of Curvature Radius in Bonnet Polishing Convex Surface
SONG Jianfeng; YAO Yingxue
2015-01-01
The bonnet tool polishing is a novel, advanced and ultra-precise polishing process, by which the freeform surface can be polished. However, during the past few years, not only the key technology of calculating the dwell time and controlling the surface form in the bonnet polishing has been little reported so far, but also little attention has been paid to research the material removal function of the convex surface based on the geometry model considering the influence of the curvature radius. Firstly in this paper, for realizing the control of the freeform surface automatically by the bonnet polishing, on the basis of the simplified geometric model of convex surface, the calculation expression of the polishing contact spot on the convex surface considering the influence of the curvature radius is deduced, and the calculation model of the pressure distribution considering the influence of the curvature radius on the convex surface is derived by the coordinate transformation. Then the velocity distribution model is built in the bonnet polishing the convex surface. On the basis of the above research and the semi-experimental modified Preston equation obtained from the combination method of experimental and theoretical derivation, the material removal model of the convex surface considering the influence of the curvature radius in the bonnet polishing is established. Finally, the validity of the model through the simulation method has been validated. This research presents an effective prediction model and the calculation method of material removal for convex surface in bonnet polishing and prepares for the bonnet polishing the free surface numerically and automatically.
The Impact of Surface Temperature Inhomogeneities on Quiescent Neutron Star Radius Measurements
Elshamouty, K. G.; Heinke, C. O.; Morsink, S. M.; Bogdanov, S.; Stevens, A. L.
2016-08-01
Fitting the thermal X-ray spectra of neutron stars (NSs) in quiescent X-ray binaries can constrain the masses and radii of NSs. The effect of undetected hot spots on the spectrum, and thus on the inferred NS mass and radius, has not yet been explored for appropriate atmospheres and spectra. A hot spot would harden the observed spectrum, so that spectral modeling tends to infer radii that are too small. However, a hot spot may also produce detectable pulsations. We simulated the effects of a hot spot on the pulsed fraction and spectrum of the quiescent NSs X5 and X7 in the globular cluster 47 Tucanae, using appropriate spectra and beaming for hydrogen atmosphere models, incorporating special and general relativistic effects, and sampling a range of system angles. We searched for pulsations in archival Chandra HRC-S observations of X5 and X7, placing 90% confidence upper limits on their pulsed fractions below 16%. We use these pulsation limits to constrain the temperature differential of any hot spots, and to then constrain the effects of possible hot spots on the X-ray spectrum and the inferred radius from spectral fitting. We find that hot spots below our pulsation limit could bias the spectroscopically inferred radius downward by up to 28%. For Cen X-4 (which has deeper published pulsation searches), an undetected hot spot could bias its inferred radius downward by up to 10%. Improving constraints on pulsations from quiescent LMXBs may be essential for progress in constraining their radii.
A LINE SEARCH AND TRUST REGION ALGORITHM WITH TRUST REGION RADIUS CONVERGING TO ZERO
Jin-yan Fan; Wen-bao Ai; Qun-ying Zhang
2004-01-01
In this paper, we present a new line search and trust region algorithm for unconstrained optimization problem with the trust region radius converging to zero. The new trust region algorithm performs a backtracking line search from the failed. Point instead of resolving the subproblem when the trial step results in an increase in the objective function. We show that the algorithm preserves the convergence properties of the traditional trust region algorithms. Numerical results are also given.
Understanding the proton radius puzzle: Nuclear structure effects in light muonic atoms
Ji Chen
2016-01-01
Full Text Available We present calculations of nuclear structure effects to the Lamb shift in light muonic atoms. We adopt a modern ab-initio approach by combining state-of-the-art nuclear potentials with the hyperspherical harmonics method. Our calculations are instrumental to the determination of nuclear charge radii in the Lamb shift measurements, which will shed light on the proton radius puzzle.
Every timelike geodesic in anti--de Sitter spacetime is a circle of the same radius
Sokołowski, Leszek M
2016-01-01
We refine and analytically prove an old proposition due to Calabi and Markus on the shape of timelike geodesics of anti--de Sitter space in the ambient flat space. We prove that each timelike geodesic forms in the ambient space a circle of the radius determined by $\\Lambda$, lying on a Euclidean two--plane. Then we outline an alternative proof for $AdS_4$. We also make a comment on the shape of timelike geodesics in de Sitter space.
Analytical description of extension, torque and supercoiling radius of a stretched twisted DNA
Neukirch, Sébastien; Marko, John F.
2011-01-01
We study the mixture of extended and supercoiled DNA that occurs in a twisted DNA molecule under tension. Closed-form asymptotic solutions for the supercoiling radius, extension and torque of the molecule are obtained in the high-force limit where electrostatic and elastic effects dominate. We demonstrate that experimental data obey the extension and torque scaling laws apparent in our formulae, in the regime where thermal fluctuation effects are quenched by applied force.
Galton-Watson分支过程的谱半径%SPECTRAL RADIUSES OF THE GALTON-WATSON BRANCHING PROCESSES
徐群芳; 赵敏智; 应坚刚
2006-01-01
The spectral radiuses of Galton-Watson branching processes which describes the speed of the process escaping from any state are calculated.Under the condition of irreducibility,it is show that this is equal to the spectral radius of Jacobi matrix of its generating function.
Martin, Michael J.
2004-01-01
With new and inexpensive computer-based methods, measuring the speed of light and the Earth's radius--historically difficult endeavors--can be simple enough to be tackled by high school and college students working in labs that have limited budgets. In this article, the author describes two methods of estimating the Earth's radius using two…
Radius expansion bursts from the neutron star transient XTE J1701-462; a new distance estimate
Lin, D.; Homan, J.; Remillard, R.; Wijnands, R.
2007-01-01
A detailed spectral analysis of the second and third type-I X- ray bursts from the neutron star transient XTE J1701-462 (detected on July 20 and July 25, see also ATel #1165) reveals clear photospheric radius expansion in both of them. The bursts show radius expansion for about 2-3 seconds, with the
[Effect of age and anti-osteoporotic drugs on bone strength and structure of the distal radius].
Uchiyama, Shigeharu
2013-07-01
The distal radius constitutes a proximal part of the wrist joint, which bears axial load from the carpal bones. Based on the biomechanical experiments, the load transmitted from the carpal bones to the distal articular surface of the radius is greater to the lunate fossa than the scaphoid fossa. The findings are consistent with the results obtained from HR-pQCT analysis of the distal radius. As ageing, bone mineral densities of the distal radius decrease, and structures of the cortical and trabecular bones also deteriorate. Such deterioration can be prevented by osteoporotic medicines such as PTH or bisphosphonate. Denosumab has been shown to increase mechanical indices of the bone structure of the distal radius. The distal radius of the individual is fractured when the load over approximately 5 times (2.5SD) of the weight is applied. It is possible to predict load of fracture in the distal radius from the results of DXA derived BMD or HR-pQCT derived bone parameters. We should not miss the opportunity of treatment for osteoporosis when the patients with fragility distal radius fracture are seen.
The effective attraction radius (EAR) of an attractive pheromone-baited trap was defined as the radius of a passive “sticky” sphere that would intercept the same number of flying insects as the attractant. The EAR for a particular attractant and insect species in nature is easily determined by a cat...
A Revised Broad-line Region Radius and Black Hole Mass for the Narrow-line Seyfert 1 NGC 4051
Denney, K. D.; Watson, L. C.; Peterson, B. M.
2009-01-01
) radius and the optical continuum luminosity—the R BLR-L relationship. Our new measurements of the lag time between variations in the continuum and Hß emission line made from spectroscopic monitoring of NGC 4051 lead to a measured BLR radius of R BLR = 1.87+0.54 -0.50 light days and black hole mass of M...
Martin, Michael J.
2004-01-01
With new and inexpensive computer-based methods, measuring the speed of light and the Earth's radius--historically difficult endeavors--can be simple enough to be tackled by high school and college students working in labs that have limited budgets. In this article, the author describes two methods of estimating the Earth's radius using two…
Interior phase transformations and mass-radius relationships of silicon-carbon planets
Wilson, Hugh F. [CSIRO Materials Science and Engineering, Parkville, Victoria 3052 (Australia); Militzer, Burkhard, E-mail: hughfw@gmail.com [Department of Earth and Planetary Science and Department of Astronomy, University of California, Berkeley, CA 94720 (United States)
2014-09-20
Planets such as 55 Cancri e orbiting stars with a high carbon-to-oxygen ratio may consist primarily of silicon and carbon, with successive layers of carbon, silicon carbide, and iron. The behavior of silicon-carbon materials at the extreme pressures prevalent in planetary interiors, however, has not yet been sufficiently understood. In this work, we use simulations based on density functional theory to determine high-pressure phase transitions in the silicon-carbon system, including the prediction of new stable compounds with Si{sub 2}C and SiC{sub 2} stoichiometry at high pressures. We compute equations of state for these silicon-carbon compounds as a function of pressure, and hence derive interior structural models and mass-radius relationships for planets composed of silicon and carbon. Notably, we predict a substantially smaller radius for SiC planets than in previous models, and find that mass radius relationships for SiC planets are indistinguishable from those of silicate planets. We also compute a new equation of state for iron. We rederive interior models for 55 Cancri e and are able to place more stringent restrictions on its composition.
G. Esteve-Asensio
2009-01-01
Full Text Available We propose and compare three novel heuristics for the calculation of the optimal cell radius in mobile networks based on Wideband Code Division Multiple Access (WCDMA technology. The proposed heuristics solve the problem of the load assignment and cellular radius calculation. We have tested our approaches with experiments in multiservices scenarios showing that the proposed heuristics maximize the cell radius, providing the optimum load factor assignment. The main application of these algorithms is strategic planning studies, where an estimation of the number of Nodes B of the mobile operator, at a national level, is required for economic analysis. In this case due to the large number of different scenarios considered (cities, towns, and open areas other methods than simulation need to be considered. As far as we know, there is no other similar method in the literature and therefore these heuristics may represent a novelty in strategic network planning studies. The proposed heuristics are implemented in a strategic planning software tool and an example of their application for a case in Spain is presented. The proposed heuristics are used for telecommunications regulatory studies in several countries.
The Neutron Star Mass-Radius Relation and the Equation of State of Dense Matter
Steiner, Andrew W; Brown, Edward F
2012-01-01
The equation of state (EOS) of dense matter has been a long-sought goal of nuclear physics. Equations of state generate unique mass versus radius (M-R) relations for neutron stars, the ultra-dense remnants of stellar evolution. In this work, we determine the neutron star mass-radius relation and, based on recent observations of both transiently accreting and bursting sources, we show that the radius of a 1.4 solar mass neutron star lies between 10.4 and 12.9 km, independent of assumptions about the composition of the core. We show, for the first time, that these constraints remain valid upon removal from our sample of the most extreme transient sources or of the entire set of bursting sources; our constraints also apply even if deconfined quark matter exists in the neutron star core. Our results significantly constrain the dense matter EOS and are, furthermore, consistent with constraints from both heavy-ion collisions and theoretical studies of neutron matter. We predict a relatively weak dependence of the s...
Laser confocal measurement system for curvature radius of lenses based on grating ruler
Tian, Jiwei; Wang, Yun; Zhou, Nan; Zhao, Weirui; Zhao, Weiqian
2015-02-01
In the modern optical measurement field, the radius of curvature (ROC) is one of the fundamental parameters of optical lens. Its measurement accuracy directly affects the other optical parameters, such as focal length, aberration and so on, which significantly affect the overall performance of the optical system. To meet the demand of measurement instruments for radius of curvature (ROC) with high accuracy in the market, we develop a laser confocal radius measurement system with grating ruler. The system uses the peak point of the confocal intensity curve to precisely identify the cat-eye and confocal positions and then measure the distance between these two positions by using the grating ruler, thereby achieving the high-precision measurement for the ROC. The system has advantages of high focusing sensitivity and anti-environment disturbance ability. And the preliminary theoretical analysis and experiments show that the measuring repeatability can be up to 0.8 um, which can provide an effective way for the accurate measurement of ROC.
Mann, Andrew W; Gaidos, Eric; Boyajian, Tabetha
2015-01-01
Precise and accurate parameters for late-type (late K and M) dwarf stars are important for proper characterization of any planets they host, but studies have been hampered by these stars' complex spectra and dissimilarity to the Sun. We exploited a calibrated method of spectroscopic effective temperature ($T_{\\rm{eff}}$) estimation and the Stefan-Boltzmann law to determine radii with an accuracy of 2-5% and expand the sample to 161 nearby K7-M7 dwarf stars covering a wider range of $T_{\\rm{eff}}$ and metallicity. We developed improved relations between $T_{\\rm{eff}}$, radius, and luminosity, as well as between $T_{\\rm{eff}}$ and color. Our $T_{\\rm{eff}}$-radius relation depends strongly on [Fe/H], as predicted by theory. We derived a relation between absolute $K_S$ magnitude and radius that is accurate to better than 3%. We derived bolometric correction to the $VR_CI_CgrizJHK_S$ and Gaia passbands as a function of color, accurate to 1-3%. We confronted the reliability of predictions from Dartmouth stellar evo...
HZ Her: Stellar Radius from X-ray Eclipse Observations, Evolutionary State and a New Distance
Leahy, D A
2014-01-01
Observations of HZ Her/ Her X-1 by the Rossi X-ray Timing Explorer (RXTE) covering high state eclipses of the neutron star are analyzed here. Models of the eclipse are used to measure the radius and atmospheric scale height of HZ Her, the stellar companion to the neutron star. The radius is 2.61 to 3.03 $\\times10^{11}$ cm, depending on system inclination and mass ratio(q), with accuracy of $\\sim$1 part in 1000 for given inclination and q. We fit Kurucz model stellar atmosphere models to archival optical observations. The resulting effective temperature ($T_{eff}$) of the unheated face of HZ Her is determined to be in the 2$\\sigma$ range 7440K to 7620K, and metallicity ($log(Z/Z_{\\odot})$) in the range -0.14 to +.08. The model atmosphere surface flux and new radius yield a new distance to HZ Her/ Her X-1, depending on system inclination and q. We calculate stellar evolution models for the range of allowed masses (from orbital parameters), and allowed metallicities (from optical spectrum fits). The stellar mode...
Ruschel, Paulo Henrique; Albertoni, Walter Manna
2005-03-01
The authors prospectively assess the results of surgically treated, unstable extra-articular distal radius fractures from 29 patients with good bone quality. Mean age was 49 years, ranging from 22 to 69 years; the female gender was the most frequently affected (58.6% of the cases). Surgical fixation was indicated for fractures presenting an angulation above 20 degrees , marked dorsal comminution, and radius shortening in excess of 10 mm on initial x-rays (anteroposterior and lateral views). The Kapandji technique, with intrafocal, nonthreaded Kirschner wires, was employed. Clinical data assessed anatomic aspects according to Scheck, functional aspect after Gartland and Werley, strength by Scheck's methods, and esthetic by Frykman's criteria. Functional assessment, according to Gartland and Werley, revealed 72.1% of excellent and good results at 3 months; 89.7% at 6 months; and 96.6% at 12 months. Immediate postoperative reduction was not maintained at the final follow-up at 12 months; however, that loss was not severe, and the anatomic outcome was good and excellent in 96.6% of the cases. Six patients presented complications. Four patients presented reflex sympathetic dystrophy; 1 patient had a superficial Kirschner wire infection, and another patient had radial nerve superficial branch paresthesia. The employed technique showed to be effective in the treatment of unstable, extra-articular fractures of the distal radius. It is easy to learn and to perform. The device employed has a low cost and is widely available in operation rooms.
The importance of GR for the radius of massive white dwarfs
Carvalho, Geanderson; Marinho, Rubens; Malheiro, Manuel
2015-12-17
In this work we investigate the structure of WD stars using the Tolman-Oppenheimer-Volkoff equations and compare with the Newtonian equations of gravitation in order to put in evidence the importance of the General Relativity in the study of these stars. Instead of using politropic equations of state we have solved the equations using the exact relativistic energy equation for the model of completely degenerate electron gas. We find a good fit of the TOV solution with the general EoS for the WD mass-radius diagram. We propose that our fit has to be used as relation between mass and radius for general relativistic WD instead of that Newtonian M ∼ 1/R{sup 3}, this fit is given by M = R/(a + bR + cR{sup 2} + dR{sup 3} + kR{sup 4}), where a, b, c and d are parameters and 1/k is the constant of the Newtonian mass-radius relation and it can be used in simulation study of binary systems that occurs accretion.
A Spitzer Infrared Radius for the Transiting Extrasolar Planet HD209458b
Richardson, L J; Seager, S; Deming, D; Harrington, Joseph; Seager, Sara; Deming, Drake
2006-01-01
We have measured the infrared transit of the extrasolar planet HD209458b using the Spitzer Space Telescope. We observed two primary eclipse events (one partial and one complete transit) using the 24 micron array of the Multiband Imaging Photometer for Spitzer (MIPS). We analyzed a total of 2392 individual images (10-second integrations) of the planetary system, recorded before, during, and after transit. We perform optimal photometry on the images and use the local zodiacal light as a short-term flux reference. At this long wavelength, the transit curve has a simple box-like shape, allowing robust solutions for the stellar and planetary radii independent of stellar limb darkening, which is negligible at 24 microns. We derive a stellar radius of R$_*$ = 1.06 $\\pm$ 0.07 R$_\\sun$, a planetary radius of R$_p$ = 1.26 $\\pm$ 0.08 R$_J$, and a stellar mass of 1.17 M$_\\sun$. Within the errors, our results agree with the measurements at visible wavelengths. The 24-micron radius of the planet therefore does not differ s...
Thrombocytopenia absent radius syndrome with Tetralogy of Fallot: a rare association
Kumar C
2015-03-01
Full Text Available Chetan Kumar,1 Deepak Sharma,2 Aakash Pandita,2 Sanjay Bhalerao1 1Department of Pediatrics, Madras Institute of Orthopedic and Trauma, Manapakkam, Chennai, India; 2Department of Neonatology, Fernandez Hospital, Hyderabad, India Abstract: Thrombocytopenia absent radius (TAR syndrome is a very rare and infrequently seen congenital disorder with an approximate frequency of 0.42/100,000 live births. It is associated with bilateral absence of radii, hypo-megakaryocytic thrombocytopenia, and presence of both thumbs. The other systems which are affected by TAR syndrome include skeletal, hematologic, and cardiac systems. Intracranial hemorrhages due to thrombocytopenia and cardiac disorders are a common association usually seen with this syndrome and are usual cause of death. We describe a 3-month-old infant who was diagnosed with TAR syndrome on the basis of clinical features (thrombocytopenia and bilateral absent radius bone and confirmed by genetic analysis. The patient was diagnosed to have Tetralogy of Fallot, for which the infant was managed with definitive repair and thrombocytopenia was managed with platelet transfusion. Infants with TAR syndrome should be assessed for other associated malformations of various systems and followed up regularly and parents should be counseled for associated expected complications in these patients. We report an infant with TAR syndrome with Tetralogy of Fallot, which has not been reported in medical literature until now and this is the first case of its type. Keywords: thrombocytopenia absent radius syndrome, Tetralogy of Fallot, microdeletion 1q21.1, RBM8A
Đurović Aleksandar
2005-01-01
Full Text Available Background. The use of orthoses is a questionable rehabilitation method for patients with the distal radius fracture at typical site. The aim of this study was to compare the effects of the rehabilitation on patients with radius fracture at the typical site, who wore circumferential static wrist orthoses, with those who did not wear them. Methods. Thirty patients were divided into 3 equal groups, 2 experimental groups, and 1 control group. The patients in the experimental groups were given the rehabilitation program of wearing serially manufactured (off-the-shelf, as well as custom-fit orthoses. Those in the control group did not wear wrist orthoses. Evaluation parameters were pain, edema, the range of the wrist motion, the quality of cylindrical, spherical, and pinch-spherical grasp, the strength of pinch and hand grasp, and patient's assessment of the effects of rehabilitation. Results. No significant difference in the effects of rehabilitation on the patients in experimental groups as opposed to control group was found. Patients in the first experimental group, and in control group were more satisfied with the effects of rehabilitation, as opposed to the patients in the second experimental group (p<0,05. Conclusion. The effects of circumferential static wrist orthoses in the rehabilitation of patients with distal radius fracture at the typical site were not clinically significant. There was no significant difference between the custom and off-the-shelf orthoses.
Failure of volar locking plate fixation of an extraarticular distal radius fracture: A case report
Ozer Kagan
2010-11-01
Full Text Available Abstract Background Volar locking plates provide significant structural stability to the distal radius. Failure of a volar locked plating is a rarely reported complication in the literature. Case Presentation A 40 year-old, obese female patient who presented with a displaced extraarticular distal radius fracture, underwent open reduction and internal fixation of the fracture using a volar locking plate. Radiographs taken at 10 weeks postoperatively showed failure of fixation with breakage of the four distal locking screws. A hardware removal was performed at 6 months, and the patient was then lost to follow-up. She presented again at 18 months after the first surgery, with significant pain, and radiographic signs of a radial collapse and a fracture-nonunion. A total wrist fusion was performed as the method of choice at that point in time. Conclusion Volar locked plating represents the new "gold standard" of distal radius fracture fixation. However, despite the stability provided by locking plates, hardware failure may occur and lead to a cascade of complications which will ultimately require a wrist fusion, as outlined in this case report. Additional structural support by bone grafting may be needed in selected cases of volar locked plating, particularly in patients with a high risk of developing a fracture-nonunion.
Forming characteristics of thin-walled tube bending process with small bending radius
LI Heng; YANG He; ZHAN Mei; GU Rui-Jie
2006-01-01
Currently requirements of thin-walled tube with small bending radius cause the defects such as wrinkling,overthinning and cross-section distortion more prone to occur in bending process. Based on the analysis of the forming characteristics by analytical and experimental methods,a complete 3D elastic-plastic FEM model of the process was developed using ABAQUS/Explicit code,including bending process,balls retracting and unloading process,and thus the plastic deformation characteristics with small bending radius were investigated. The main results show that: 1) The utmost deformation feature of the NC bending process is its continuous progressive deformation. 2) The occurring conditions of the defects such as wrinkling and tension instability in the process are obtained. The wrinkling is traditional on the double compressive stresses state and the tension instability is on the double tension stresses state. 3) The enhanced non-uniform deformation in thin-walled tube with small bending radius is demonstrated by comparing the stress/ strains distributions under the 1.5D and 1D bending conditions. 4) For 1D small bending process,a new method-"stepped mandrel retraction" is proposed to improve the bending quality in experiment according to the FE simulation. The simulation results are verified by experiment.
Determining the Co-Rotation Radius of Nearby Spiral Galaxies Using Spiral Arm Overlays
Shameer Abdeen, Mohamed; Kennefick, Daniel; Kennefick, Julia D.; Pour Imani, Hamed; Shields, Douglas W.; Eufrasio, Rafael; Berlanga Medina, Jazmin; Monson, Erik
2017-01-01
Density wave theory, originally proposed by C.C. Lin and Frank Shu (Lin & Shu 1964), views the spiral arm structures in spiral galaxies as density waves that propagates through the galactic disk. Resonances within orbits create standing wave patterns of density waves that we observe as spiral arms. The theory predicts the existence of a radius known as the co-rotation radius in which the spiral arm pattern speed matches the velocities of the stars within the disk. We introduce a novel way of determining the co-rotation radius, based on an image overlaying technique, which involves tracing the arms of spiral galaxies on images observed from different wavelengths. For the purpose of this study, 12 nearby galaxies were analyzed from four different wavelengths using pitch angle measurements from a previous study (Hamed et al. 2016). We used optical wavelength images (B-Band,440 nm), two infrared wavelength (Infrared; 3.6 µm and 8 µm) Spitzer Space Telescope images and ultraviolet images from GALEX. The results were verified by checking against results compiled from the literature.
Implications of a matter-radius measurement for the structure of Carbon-22
Acharya, B., E-mail: acharyab@phy.ohiou.edu [Department of Physics and Astronomy, Ohio University, Athens, OH 45701 (United States); Ji, C., E-mail: jichen@triumf.ca [Department of Physics and Astronomy, Ohio University, Athens, OH 45701 (United States); TRIUMF, 4004 Wesbrook Mall, Vancouver, BC V6T 2A3 (Canada); Phillips, D.R., E-mail: phillips@phy.ohiou.edu [Department of Physics and Astronomy, Ohio University, Athens, OH 45701 (United States)
2013-06-10
We study Borromean 2n-halo nuclei using effective field theory. We compute the universal scaling function that relates the mean-square matter radius of the 2n halo to dimensionless ratios of two- and three-body energies. We use the experimental value of the rms matter radius of {sup 22}C measured by Tanaka et al. (2010) [3] to put constraints on its 2n separation energy and the {sup 20}C–n virtual energy. We also explore the consequences of these constraints for the existence of excited Efimov states in this nucleus. We find that, for {sup 22}C to have an rms matter radius within 1–σ of the experimental value, the two-neutron separation energy of {sup 22}C needs to be below 100 keV. Consequently, this three-body halo system can have an excited Efimov state only if the {sup 20}C–n system has a resonance within 1 keV of the scattering threshold.
Estimation of the radius of a star based on its effective temperature and surface gravity
Sichevskij, S. G.
2016-06-01
Amethod for determining the radius of a star using its effective temperature and surface gravity is proposed. The method assumes that the relationship between the radius, effective temperature, and surface gravity can be approximated using models for the internal structure and evolution of the star. The method is illustrated using the Geneva-Toulouse evolutionary computations for two metal abundances—solar and one-tenth of solar. Analysis of the systematic errors shows that the accuracy of the method is better than 10% over most part of the Hertzsprung-Russell diagram, and is about 5% for main-sequence stars. The maximum relative systematic error due to the simplifications underlying the method is about 15%. A test using eclipsing binaries confirms the viability of the proposed method for estimating stellar radii. In the region of the main sequence, systematic deviations do not exceed 2%, and the relative standard deviation is ≤4.7%. It is expected that th maximum relative error over the rest of the Hertzsprung-Russell diagram will likewise be close to the systematic error, about 15-20%. The method is applied to estimate the radii of model stellar atmospheres. Such estimates can be used to synthesize the color index and luminosity of a star. The method can be used whenever accuracies of about 10% in the estimated stellar radius and luminosity are acceptable.
Geneva University - Measurement of the Lamb shift in muonic hydrogen: the proton radius puzzle
2010-01-01
GENEVA UNIVERSITY École de physique Département de physique nucléaire et corspusculaire 24, quai Ernest-Ansermet 1211 GENEVA 4 Tel: (022) 379 62 73 Fax: (022) 379 69 92 Wednesday 12 May 2010 PARTICLE PHYSICS SEMINAR at 17.00 hrs – Stückelberg Auditorium Measurement of the Lamb shift in muonic hydrogen: the proton radius puzzle Dr Aldo Antogninia , CREMA Collaboration, Max Planck Institute, Germany At the Paul Scherrer Institut, Switzerland, we have measured several 2S-2P transition frequencies in muonic hydrogen (µp) and deuterium (µd) by means of laser spectroscopy. This results in an order of magnitude improvement on the rms charge radius values of the proton and the deuteron. Additionally the Zemach radii and the deuteron polarizability are also inferred. The new proton radius value is deduced with a relative accuracy of 0.1% but strongly disagrees from CODATA. The origin of this discrepancy is not yet known. It may come from theo...
The mass and radius evolution of globular clusters in tidal fields
Gieles, Mark
2013-01-01
We present a simple theory for the evolution of initially compact clusters in a tidal field. The fundamental ingredient of the model is that a cluster conducts a constant fraction of its own energy through the half-mass radius by two-body interactions every half-mass relaxation time. This energy is produced in a self-regulative way in the core by an (unspecified) energy source. We find that the half-mass radius increases during the first part (roughly half) of the evolution and decreases in the second half, while the escape rate is constant and set by the tidal field. We present evolutionary tracks and isochrones for clusters in terms of cluster half-mass density, cluster mass and galacto-centric radius. We find substantial agreement between model isochrones and Milky Way globular cluster parameters, which suggests that there is a balance between the flow of energy and the central energy production for almost all globular clusters. We also find that the majority of the globular clusters are still expanding to...
Neutron star mass-radius relation with gravitational field shielding by a scalar field
Bo-Jun Zhang; Tian-Xi Zhang; Padmaja Guggilla; Mostafa Dokhanian
2013-01-01
The currently well-developed models for equations of state (EoSs) have been severely impacted by recent measurements of neutron stars with a small radius and/or large mass.To explain these measurements,the theory of gravitational field shielding by a scalar field is applied.This theory was recently developed in accordance with the five-dimensional (5D) fully covariant Kaluza-Klein (KK) theory that has successfully unified Einstein's general relativity and Maxwell's electromagnetic theory.It is shown that a massive,compact neutron star can generate a strong scalar field,which can significantly shield or reduce its gravitational field,thus making it more massive and more compact.The mass-radius relation developed under this type of modified gravity can be consistent with these recent measurements of neutron stars.In addition,the effect of gravitational field shielding helps explain why the supernova explosions of some very massive stars (e.g.,40 M⊙ as measured recently) actually formed neutron stars rather than black holes as expected.The EoS models,ruled out by measurements of small radius and/or large mass neutron stars according to the theory of general relativity,can still work well in terms of the 5D fully covariant KK theory with a scalar field.
Chandrashekhar V. Mudgal
2017-04-01
Full Text Available BACKGROUND A study was done to evaluate the effect of the ligamentotaxis in the management of intraarticular fractures of the distal radius. MATERIALS AND METHODS 34 patients were studied prospectively between March 2014 and February 2016. All patients had intraarticular fracture of distal end of radius and all were treated with ligamentotaxis after closed reduction with fluoroscopic guidance. The follow-up period was 12 months. At the time of surgery, the mean age was 45.29 years. RESULTS In all fracture cases, the mean of fracture union was 5.8 weeks. During the final follow-up, the mean range of motion was 55.30 in flexion, 56.60 in extension, 21.0 in ulnar deviation, 9.00 in radial deviation, 70.30 in pronation and 67.10 in supination. According to the scoring system of Gartland and Werley, the clinical and functional outcomes showed that 15 patients (44.1% had excellent results, 14 (41.1% had good results, 3 (8.8% had fair results and 2 (5.8% had poor results. CONCLUSION Closed reduction under fluoroscopic image guidance and the ligamentotaxis is useful and effective in the treatment of intraarticular fractures of the distal radius.
Leconte, Jérémy; Chabrier, Gilles
2011-01-01
We quantify the systematic impact of the non-spherical shape of transiting planets and brown dwarfs, due to tidal forces and rotation, on the observed transit depth. Such a departure from sphericity leads to a bias in the derivation of the transit radius from the light curve and affects the comparison with planet structure and evolution models which assume spherical symmetry. As the tidally deformed planet projects its smallest cross section area during the transit, the measured effective radius is smaller than the one of the unperturbed spherical planet. This effect can be corrected by calculating the theoretical shape of the observed planet. We derive simple analytical expressions for the ellipsoidal shape of a fluid object (star or planet) accounting for both tidal and rotational deformations and calibratre it with fully numerical evolution models in the 0.3Mjup-75Mjup mass range. Our calculations yield a 20% effect on the transit depth, i.e. a 10% decrease of the measured radius, for the extreme case of a...
Trabecular and cortical microstructure and fragility of the distal radius in women.
Bala, Yohann; Bui, Quang Minh; Wang, Xiao-Fang; Iuliano, Sandra; Wang, Qingju; Ghasem-Zadeh, Ali; Rozental, Tamara D; Bouxsein, Mary L; Zebaze, Roger M D; Seeman, Ego
2015-04-01
Fragility fractures commonly involve metaphyses. The distal radius is assembled with a thin cortex formed by fusion (corticalization) of trabeculae arising from the periphery of the growth plate. Centrally positioned trabeculae reinforce the thin cortex and transfer loads from the joint to the proximal thicker cortical bone. We hypothesized that growth- and age-related deficits in trabecular bone disrupt this frugally assembled microarchitecture, producing bone fragility. The microarchitecture of the distal radius was measured using high-resolution peripheral quantitative computed tomography in 135 females with distal radial fractures, including 32 girls (aged 7 to 18 years), 35 premenopausal women (aged 18 to 44 years), and 68 postmenopausal women (aged 50 to 76 years). We also studied 240 fracture-free controls of comparable age and 47 healthy fracture-free premenopausal mother-daughter pairs (aged 30 to 55 and 7 to 20 years, respectively). In fracture-free girls and pre- and postmenopausal women, fewer or thinner trabeculae were associated with a smaller and more porous cortical area (r = 0.25 to 0.71 after age, height, and weight adjustment, all p radius.
Monitoring the Solar Radius from the Royal Observatory of the Spanish Navy since 1773
Vaquero, J. M.; Gallego, M. C.; Ruiz-Lorenzo, J. J.; López-Moratalla, T.; Carrasco, V. M. S.; Aparicio, A. J. P.; González-González, F. J.; Hernández-García, E.
2016-08-01
The solar diameter has been monitored at the Royal Observatory of the Spanish Navy (today the Real Instituto y Observatorio de la Armada: ROA) almost continuously since its creation in 1753 ( i.e. during the past 250 years). After a painstaking effort to collect data in the historical archive of this institution, we present here the data of the solar semidiameter from 1773 to 2006, making up an extensive new database for solar-radius measurements, which can be considered. We have calculated the solar semidiameter from the transit times registered by the observers (except for values of the solar radius from the modern Danjon astrolabe, which were published by ROA). These data were analysed to reveal any significant long-term trends, but no such trends were found. Therefore, the data sample confirms the constancy of the solar diameter during the past 250 years (approximately) within instrumental and methodological limits. Moreover, no relationship between solar radius and the new sunspot-number index has been found from measurements of the ROA. Finally, the mean value for the solar semidiameter (with one standard deviation) calculated from the observations made in the ROA (1773 - 2006), after applying corrections for refraction and diffraction, is equal to 958.87^''±1.77^''.
A Measurement of Radius Inflation in the Pleiades and Its Relation to Rotation and Lithium Depletion
Somers, Garrett; Stassun, Keivan G.
2017-03-01
Precise measurements of eclipsing binary parameters and statistical studies of young clusters have suggested that some magnetically active low-mass dwarfs possess radii inflated by ∼5%–15% relative to theoretical expectations. If true, this effect should be pronounced in young open clusters, due to the rapid rotation and strong magnetic activity of their most extreme members. We explore this possibility by determining empirical radii for 83 members of the nearby Pleiades open cluster, using spectral energy distribution fitting to establish {{ F }}{bol} with a typical accuracy of ≈3% together with color and spectro-photometric indices to determine {T}{eff}. We find several Pleiades members with radii inflated above radius-{T}{eff} models from state-of-the-art calculations, and apparent dispersions in radii for the K-dwarfs of the cluster. Moreover, we demonstrate that this putative radius inflation correlates strongly with rotation rate, consistent with inflation of young stars by magnetic activity and/or starspots. We argue that this signal is not a consequence of starspot-induced color anomalies, binarity, or depth effects in the cluster, employing Gaia DR1 distances as a check. Finally, we consider the lithium abundances of these stars, demonstrating a triple correlation between rotation rate, radius inflation, and enhanced lithium abundance. Our result—already significant to ∼99.99% confidence—provides strong support for a magnetic origin of the inflated radii and lithium dispersion observed in young, low-mass stars.
Amir Pourmoghaddam
2016-04-01
Full Text Available Total knee arthroplasty is used as the treatment plan for patients with end-stage osteoarthrosis associated with severely affected function. Although TKA has been used for many years, some patients have reported overall dissatisfaction regarding the outcome. This may be due to the complexity of the joint design. In recent years, the concept of single-radius knee prosthetics is gaining more popularity as many studies have discussed biomechanical and clinical benefits of such design compared to traditionally used multi-radius implants. In this study, we report the outcome of 78 patients who were treated by TKA utilizing a relatively new single-radius implant, Unity. Results showed that all subjects reported good outcomes as expressed by significant improvement in their Knee Injury and Osteoarthritis Outcome Scores at 1-year post-operative. The symptom, pain, and ADL subscores demonstrated significant improvement in patients with scores twice the pre-operative value, while the average improvement in sport and quality of life subscores showed even greater improvement with scores three times the pre-operative value.
A Constraint of Black Hole Mass and the Inner Edge Radius of Relativistic Accretion Disc
HE Liang; HUANG Chang-Yin; WANG Ding-Xiong
2011-01-01
A constraint to black hole(BH)accretion has previously been derived for the inner edge fixed at the innermost stable circular orbit(ISCO) and the innermost bound circular orbit(IBCO). This constraint is referred to as the mass-radius(MR) relation in this study, and the validity of the MR relation is discussed for different cases. It is shown that the product of the BH mass and the inner edge radius decreases monotonically in the accretion process for the inner edge located between IBCO and ISCO. In addition, we discuss the validity of the MR relation by considering the magnetic coupling(MC) effects of a Kerr BH with its surrounding disc. Although theoretically the product of the BH mass and the radius of ISCO increases(decreases) with time for a BH spin greater(less)than some critical value in the MC process, this relation is approximately valid for an Eddington accretion rate persisting for a rather long time, such as more than 10(6) years. Finally ,we discuss the possible application of the MR relation to astrophysics.
Radius of clusters at the percolation threshold: A position space renormalization group study
Family, Fereydoon; Reynolds, Peter J.
1981-06-01
Using a direct position-space renormalization-group approach we study percolation clusters in the limit s → ∞, where s is the number of occupied elements in a cluster. We do this by assigning a fugacity K per cluster element; as K approaches a critical value K c , the conjugate variable s → ∞. All exponents along the path ( K-K c ) → 0 are then related to a corresponding exponent along the path s → ∞. We calculate the exponent ρ, which describes how the radius of an s-site cluster grows with s at the percolation threshold, in dimensions d=2, 3. In d=2 our numerical estimate of ρ=0.52±0.02, obtained from extrapolation and from cell-to-cell transformation procedures, is in agreement with the best known estimates. We combine this result with previous PSRG calculations for the connectedness-length exponent ν, to make an indirect test of cluster-radius scaling by calculating the scaling function exponent σ using the relation σ=ρ/ν. Our result for σ is in agreement with direct Monte-Carlo calculations of σ, and thus supports the cluster-radius scaling assumption. We also calculate ρ in d=3 for both site and bond percolation, using a cell of linear size b=2 on the simple-cubic lattice. Although the result of such small-cell calculations are at best only approximate, they nevertheless are consistent with the most recent numerical estimates.
Soubeyrand, M; Ciais, G; Wassermann, V; Kalouche, I; Biau, D; Dumontier, C; Gagey, O
2011-10-01
Disruption of the interosseous membrane is easily missed in patients with Essex-Lopresti syndrome. None of the imaging techniques available for diagnosing disruption of the interosseous membrane are completely dependable. We undertook an investigation to identify whether a simple intra-operative test could be used to diagnose disruption of the interosseous membrane during surgery for fracture of the radial head and to see if the test was reproducible. We studied 20 cadaveric forearms after excision of the radial head, ten with and ten without disruption of the interosseous membrane. On each forearm, we performed the radius joystick test: moderate lateral traction was applied to the radial neck with the forearm in maximal pronation, to look for lateral displacement of the proximal radius indicating that the interosseous membrane had been disrupted. Each of six surgeons (three junior and three senior) performed the test on two consecutive days. Intra-observer agreement was 77% (95% confidence interval (CI) 67 to 85) and interobserver agreement was 97% (95% CI 92 to 100). Sensitivity was 100% (95% CI 97 to 100), specificity 88% (95% CI 81 to 93), positive predictive value 90% (95% CI 83 to 94), and negative predictive value 100%). This cadaveric study suggests that the radius joystick test may be useful for detecting disruption of the interosseous membrane in patients undergoing open surgery for fracture of the radial head and is reproducible. A confirmatory study in vivo is now required.
Strength prediction of the distal radius by bone densitometry--evaluation using biomechanical tests.
Eckstein, Felix; Kuhn, Volker; Lochmüller, Eva-Maria
2004-03-01
Osteoporotic fractures represent an important medical problem as they are often early predictors of future fractures at other skeletal sites. The distal radius is one such fracture site. To determine the individual's risk of fracture, different measurement techniques have been developed. These methods differ in physical background, measurement site, output parameters, and cost. If correctly applied, biomechanical testing can be an efficient tool for the preclinical evaluation of these techniques. With biomechanical testing it is possible to determine the structural strength of bone which can then be correlated with various densitometric parameters. Here we will review experimental work performed in this context. Biomechanical testing conditions vary considerably from study to study with 3-point bending (shaft), axial compression (metaphysis), and fall simulations being some of the techniques used. Experimental evidence suggests that site-specific osteodensitometric measurements can predict the mechanical strength of the distal radius with moderate to high accuracy, but that measurements at remote sites display considerably lower predictive value. Geometry-based parameters of cortical bone are also good predictors, but have not been shown to offer significant advantage over measurement of bone mass. Some (but not all) studies have found that quantitative ultrasound and microstructural parameters contribute significant additional information to bone mass measurement. The most accurate prediction of distal radius fractures, however, appears to be (patient-specific) microstructural finite element modeling.
Characterization of dynamic three-dimensional strain fields in the canine radius.
Coleman, John C; Hart, Richard T; Owan, Ichiro; Tankano, Yuichi; Burr, David B
2002-12-01
This note describes a method to approximate the 3-D mechanical environment of a long bone during a normal daily activity. Our specific goal was to characterize the temporal and spatial strain distributions in the mid-shaft region of the canine radius during gait. Direct measurement of strains along the entire surface of in vivo bone is not feasible, so we employed a combination of experimental measurements and numerical interpolation techniques to approximate the time-varying longitudinal strain distribution. Using standard in vivo strain gauging techniques, we measured dynamic strains at nine locations (three locations on each of three cross sections, data pooled from two experimental animals) on the canine radius during trotting gait. These in vivo strain measurements were then used to approximate the time course of the strain field for the entire radius mid-shaft region using a 3-D numerical interpolation scheme using finite element basis functions. Despite limitations in the present implementation of the method, the results show that there are considerable time-dependent variations in the strain distribution occurring at different transverse sections along the length of the diaphysis with substantial anteroposterior bending and rotation of neutral axis locations during the gait cycle.
Radius of {sup 12}C in the excited 2{sub 2} {sup +} Hoyle state
Ogloblin, A.A.; Danilov, A.N.; Demyanova, A.S. [RRC Kurchatov Institute, Moscow (Russian Federation); Belyaeva, T.L. [Universidad Autonoma del Estado de Mexico, C.P. 50000, Toluca (Mexico); Goncharov, S.A. [Lomonosov Moscow State University, Moscow (Russian Federation)
2013-04-15
The differential cross sections of the inelastic {alpha} + {sup 12}C scattering leading to the excitation of the short-lived 2{sub 2} {sup +} (E{sub x} = 9.84 or 9.6 MeV) state in {sup 12}C have been analysed within a modified diffraction model. We determined the diffraction radii of {sup 12}C in this excited state at E{sub {alpha}} = 386 and 240 MeV and compared them with the diffraction radius for the 0{sub 2} {sup +} (E{sub x} = 7.65 MeV) Hoyle state. We found that the rms radii for the 2{sub 2} {sup +} state is left angle R(2{sub 2} {sup +}) right angle = 3.07 {+-} 0.13fm, which agrees well with the rms radius of the 0{sub 2} {sup +}, 7.65 MeV Hoyle state and is a factor of 1.3 larger than the rms radius for the ground state of {sup 12}C. The similarity between the rms radii of the 0{sub 2} {sup +} and 2{sub 2} {sup +} states provides a strong argument in favor of a hypothesis that the 2{sub 2} {sup +} state is the first member of a rotational band based on the 0{sub 2} {sup +} Hoyle state. (orig.)
Exact solution of gyration radius of individual's trajectory for a simplified human mobility model
Yan, Xiao-Yong; Zhou, Tao; Wang, Bing-Hong
2010-01-01
Gyration radius of individual's trajectory plays a key role in quantifying human mobility patterns. Of particular interests, empirical analyses suggest that the growth of gyration radius is slow versus time except the very early stage and may eventually arrive to a steady value. However, up to now, the underlying mechanism leading to such a possibly steady value has not been well understood. In this Letter, we propose a simplified human mobility model to simulate individual's daily travel with three sequential activities: commuting to workplace, going to do leisure activities and returning home. With the assumption that individual has constant travel speed and inferior limit of time at home and work, we prove that the daily moving area of an individual is an ellipse, and finally get an exact solution of the gyration radius. The analytical solution well captures the empirical observation reported in [M. C. Gonz`alez et al., Nature, 453 (2008) 779]. We also find that, in spite of the heterogeneous displacement ...
The hominoid proximal radius: re-interpreting locomotor behaviors in early hominins.
Patel, Biren A
2005-04-01
Studies of fossil hominins are traditionally taxonomically narrow and often exclude comparisons with hylobatids. Hence, results of functional analyses of postcrania, interpreted as indicating that early hominins are "African-ape-like" in their postcranial skeletons and positional behaviors, may reflect an artifact of inadequate taxonomic and morphological breadth of the comparative sample. To address this problem and better understand early hominin positional behaviors, this study included hylobatids in a comparative analysis, focusing on the hominoid elbow joint. Specifically, morphometric variables of the proximal radius were derived from measurements from a sample of all genera of extant hominoids and casts of extinct hominin species. Univariate and multivariate analyses were performed on these data. Results show that early hominins are morphologically diverse and are not, as a group, similar to any one extant group. Instead, the fossils resemble Pan, Gorilla, and Hylobates, and are not like modern Homo sapiens or Pongo. This suggests that the morphology of Hylobates may reflect a morphotype for all later hominoids, thus complicating the functional interpretations of fossil hominins. The implications of these results are that the proximal radius is not a sensitive indicator of locomotor behavior among hominoids since the morphology in hylobatids and Gorilla and Pan is similar despite widely varying positional repertoires. Furthermore, inferences of function from form in extinct hominins can be drastically affected by the comparative outgroup selection. A re-evaluation of the functional morphology of the proximal radius in early hominins is addressed.
Obert Laurent
2015-01-01
Full Text Available Few studies on the anatomy of the radial epiphysis have been published in the past 10 years. However, with the availability of new intra- and extra-medullary implants and the recent rash of avoidable iatrogenic injuries, now is the time for a more detailed description of the metaphyseal-epiphyseal regions in the distal radius. Published studies on distal radius anatomy in recent years have focused on three aspects: distal limit and watershed line, dorsal tubercle, and wrist columns. Furthermore, a fresh look at distal radius biomechanics shows that the loads experienced by the distal radius vary greatly. This information should be taken into account during volar plating of distal radius fractures.
Jian Guangde; Huang Lin; Qiu Xiaoming
2005-01-01
The assembling stabilizing effect of the finite Larmor radius (FLR) and the sheared axial flow (SAF) on the Rayleigh-Taylor instability in Z-pinch implosions is studied by means of the incompressible finite Larmor radius magnetohydrodynamic (MHD) equations. The finite Larmor radius effects are introduced in the momentum equation with the sheared axial flow through an anisotropic ion stress tensor. In this paper a linear mode equation is derived that is valid for arbitrary kL, where k is the wave number and L is the plasma shell thickness. Numerical solutions are presented. The results indicate that the short-wavelength modes of the RayleighTaylor instability are easily stabilized by the individual effect of the finite Larmor radius or the sheared axial flow. The assembling effects of the finite Larmor radius and sheared axial flow can heavily mitigate the Rayleigh-Taylor instability, and the unstable region can be compressed considerably.
Prabhati Rani Mishra
2016-12-01
Full Text Available BACKGROUND Most common fracture in elderly patients is distal radius fracture. The most common method of management is closed reduction and immobilisation. The aim of the study is to compare the analgesic effects of haematoma block and general anaesthesia for closed reduction of distal fracture of radius. MATERIALS AND METHODS A prospective randomised controlled study was carried out among 100 patients of age group between 15-70 years of either sex who had fracture distal radius between 2015-2016. The patients having multiple fractures, pathological fractures or suffering from any organic diseases were excluded from the study. After taking informed written consent, the patients were randomised into two equal groups. In group A, reduction of fracture was done following administration of IV propofol and in group B after infiltration with 2% lignocaine into fracture haematoma site. Pain score was compared by VAS before, during and after manipulation in both the groups. Time taken from presentation at emergency department to reduction and discharge from hospital was also compared. Statistical analysis was done by applying SPSS software. RESULTS 100 patients of mean age 42.5 years, male: female 43:57 with fracture distal radius were studied. Mean time from admission to fracture reduction in group A was 2.64±0.93 hours and in group B 0.90±0.45 hours (P=0.0001. Discharge time from hospital after reduction of fracture in group A was 4.24±0.94 hours and in group B 0.75±0.2 hours (P=0.0001. VAS during reduction in group A was 0 and in group B 0.98±0.8 (P=0.0001. 10 minutes after reduction VAS in group A was 2.28±0.24 and group B 0.72±0.45 (P=0.0001. CONCLUSION For closed reduction of distal radius fracture, haematoma block with lignocaine is safe and effective alternative to intravenous general anaesthesia with propofol.
Paritosh Gogna; Harpal Singh Selhi; Rohit Singla; Mukul Mohindra; Amit Batra; Reetadyuti Mukhopadhyay; Rajesh Rohilla
2013-01-01
Objective:Metaphyseal-diaphyseal fractures of the distal radius are a major treatment dilemma and orthopaedic surgeons have to pay due consideration to restoration of anatomy of distal radius together with rotation of the radial shaft and maintenance of radial bow and interosseous space.We performed this study to evaluate the clinic-radiological outcome of metaphyseal-diaphyseal fractures of the distal radius treated with long volar locking plates.Methods:This prospective study involved 27 patients (22 males and 5 females) with metaphyseal-diaphyseal fracture of the distal radius.Their mean age was (30.12±11.48) years (range 19-52 years) and the follow-up was 26.8 months (range 22-34 months).All patients underwent open reduction and internal fixation with a long volar locking plate.According to AO/OTA classification,there were 7 type A3,13 type C2 and 7 type C3 fractures.Subjective assessment was done based on the disabilities of the arm,shoulder and hand (DASH) questionnaire.Functional evaluation was done by measuring grip strength and range of motion around the wrist and the radiological determinants included radial angle,radial length,volar angle and ulnar variance.The final assessment was done according to Gartland and Werley scoring system.Results:Postoperative radiological parameters were well maintained throughout the trial,and there was significant improvement in the functional parameters from 6 weeks to final follow-up.The average DASH scores improved from 37.5 at 6 weeks to 4.2 at final follow-up.Final assessment using Gartland and Werley scoring system revealed 66.67％(n=l8) excellent and 33.33％ (n=9) good results.There was one case of superficial infection which responded to antibiotics and another carpel tunnel syndrome which was managed conservatively.Conclusion:Volar locking plate fixation for metaphyseal-diaphyseal fractures of distal radius is associated with excellent to good functional outcome,early rehabilitation and minimal complications.
Thuillier, G.; Zhu, P.; Shapiro, A. I.; Sofia, S.; Tagirov, R.; van Ruymbeke, M.; Perrin, J.-M.; Sukhodolov, T.; Schmutz, W.
2017-07-01
Context. Despite the importance of having an accurate measurement of the solar disc radius, there are large uncertainties of its value due to the use of different measurement techniques and instrument calibration. An item of particular importance is to establish whether the value of the solar disc radius correlates with the solar activity level. Aims: The main goal of this work is to measure the solar disc radius in the near-UV, visible, and near-IR regions of the solar spectrum. Methods: Three instruments on board the PICARD spacecraft, namely the Bolometric Oscillations Sensor (BOS), the PREcision MOnitoring Sensor (PREMOS), and a solar sensor (SES), are used to derive the solar disc radius using the light curves produced when the Sun is occulted by the Moon. Nine eclipses, from 2010 to 2013, resulted in 17 occultations as viewed from the moving satellite. The calculation of the solar disc radius uses a simulation of the light curve taking into account the center-to-limb variation provided by the Non-local thermodynamic Equilibrium Spectral SYnthesis (NESSY) code. Results: We derive individual values for the solar disc radius for each viewed eclipse. Tests for a systematic variation of the radius with the progression of the solar cycle yield no significant results during the three years of measurements within the uncertainty of our measurements. Therefore, we derive a more precise radius value by averaging these values. At one astronomical unit, we obtain 959.79 arcseconds (arcsec) from the bolometric experiment; from PREMOS measurements, we obtain 959.78 arcsec at 782 nm and 959.76 arcsec at 535 nm. We found 960.07 arcsec at 210 nm, which is a higher value than the other determinations given the photons at this wavelength originate from the upper photosphere and lower chromosphere. We also give a detailed comparison of our results with those previously published using measurements from space-based and ground-based instruments using the Moon angular radius
Tonogai, Ichiro; Hamada, Yoshitaka; Hibino, Naohito; Sato, Ryosuke; Henmi, Tatsuhiko; Sairyo, Koichi
2015-01-01
Salmonella osteomyelitis of the radius in a healthy individual is very rare. We present such a case involving the distal radius of a healthy 23-year-old man without underlying disease or possible episode. He had right wrist pain for approximately 3 years, and osteolytic lesion was seen in the right distal radius. He underwent surgical treatment, and salmonella was isolated from pus in the lesion. Postoperative antibiotics successfully treated his infection. He had no sign of recurrence, but the point of entry for infection remains unknown.
Scaling properties of the radius of gyration and surface area for EF-hand calcium binding proteins
Pitulice, L. [West University of Timisoara, Department of Chemistry, Pestalozzi 16, 300115 Timisoara (Romania); Isvoran, A. [West University of Timisoara, Department of Chemistry, Pestalozzi 16, 300115 Timisoara (Romania)], E-mail: aisvoran@cbg.uvt.ro; Craescu, C.T. [INSERM U759/Institute Curie-Recherche, Centre Universitaire Paris-Sud, Batiment 112, 91405 Orsay (France); Chiriac, A. [West University of Timisoara, Department of Chemistry, Pestalozzi 16, 300115 Timisoara (Romania)
2009-04-30
In this paper, we analyze the scaling properties of both the radius of gyration and the surface area for EF-hand calcium binding proteins. These properties are different for two conformational subfamilies: proteins with extended and compact structures, respectively. The radius of gyration is a measure of the shape of protein, whereas its surface fractal dimension is a measure of its interatomic packing. Different scaling properties for the radius of gyration underline that these two subfamilies present different shapes whilst different scaling properties for the surface area reveal different strengths of their intermolecular forces. All these data suggest different mechanisms responsible for the global folding of proteins belonging to these two subfamilies.
Distal radius geometry and skeletal strength indices after peripubertal artistic gymnastics.
Dowthwaite, J N; Scerpella, T A
2011-01-01
Development of optimal skeletal strength should decrease adult bone fragility. Nongymnasts (NON): were compared with girls exposed to gymnastics during growth (EX/GYM: ), using peripheral quantitative computed tomography (pQCT) to evaluate postmenarcheal bone geometry, density, and strength. Pre- and perimenarcheal gymnastic loading yields advantages in indices of postmenarcheal bone geometry and skeletal strength. Two prior studies using pQCT have reported bone density and size advantages in Tanner I/II gymnasts, but none describe gymnasts' bone properties later in adolescence. The current study used pQCT to evaluate whether girls exposed to gymnastics during late childhood growth and perimenarcheal growth exhibited greater indices of distal radius geometry, density, and skeletal strength. Postmenarcheal subjects underwent 4% and 33% distal radius pQCT scans, yielding: 1) vBMD and cross-sectional areas (CSA) (total bone, compartments); 2) polar strength-strain index; 3) index of structural strength in axial compression. Output was compared for EX/GYM: vs. NON: , adjusting for gynecological age and stature (maturity and body size), reporting means, standard errors, and significance. Sixteen postmenarcheal EX/GYM: (age 16.7 years; gynecological age 3.4 years) and 13 NON: (age 16.2 years; gynecological age 3.6 years) were evaluated. At both diaphysis and metaphysis, EX/GYM: exhibited greater CSA and bone strength indices than NON; EX/GYM: exhibited 79% larger intramedullary CSA than NON: (p gymnastic exposure, relative to nongymnasts, postmenarcheal EX/GYM: demonstrated greater indices of distal radius geometry and skeletal strength (metaphysis and diaphysis) with greater metaphyseal trabecular vBMD; larger intramedullary cavity size was particularly striking.
Combining ergometer exercise and artificial gravity in a compact-radius centrifuge
Diaz, Ana; Trigg, Chris; Young, Laurence R.
2015-08-01
Humans experience physiological deconditioning during space missions, primarily attributable to weightlessness. Some of these adverse consequences include bone loss, muscle atrophy, sensory-motor deconditioning, and cardiovascular alteration, which may lead to orthostatic intolerance when astronauts return to Earth. Artificial gravity could provide a comprehensive countermeasure capable of challenging all the physiological systems at once, particularly if combined with exercise, thereby maintaining overall health during extended exposure to weightlessness. A new Compact Radius Centrifuge (CRC) platform was designed and built on the existing Short Radius Centrifuge (SRC) at the Massachusetts Institute of Technology (MIT). The centrifuge has been constrained to a radius of 1.4 m, the upper radial limit for a centrifuge to fit within an International Space Station (ISS) module without extensive structural alterations. In addition, a cycle ergometer has been added for exercise during centrifugation. The CRC now includes sensors of foot forces, cardiovascular parameters, and leg muscle electromyography. An initial human experiment was conducted on 12 subjects to analyze the effects of different artificial gravity levels (0 g, 1 g, and 1.4 g, measured at the feet) and ergometer exercise intensities (25 W warm-up, 50 W moderate and 100 W vigorous) on the musculoskeletal function as well as motion sickness and comfort. Foot forces were measured during the centrifuge runs, and subjective comfort and motion sickness data were gathered after each session. Preliminary results indicate that ergometer exercise on a centrifuge may be effective in improving musculoskeletal function. The combination is well tolerated and motion sickness is minimal. The MIT CRC is a novel platform for future studies of exercise combined with artificial gravity. This combination may be effective as a countermeasure to space physiological deconditioning.
Hossein Alimohammadi
2013-12-01
Full Text Available Introduction: Given the high prevalence of upper extremity fractures and increasing need to perform painless reduction in the emergency departments, the use of analgesic methods with fewer complications and more satisfaction appears to be essential. The aim of this study is comparison the nerve stimulator guided axillary block (NSAB with intravenous sedation in induction of analgesia for painless reduction of distal radius fractures. Methods: In the present randomized clinical trial, 60 patients (18-70 years of age suffered from distal radius fractures, were divided into two equal groups. One group received axillary nerve block by nerve stimulator guidance and the other procedural sedation and analgesia (PSA using midazolam/fentanyl. Onset of analgesia, duration of analgesic effect, total procedure time and pain scores were recorded using visual analogue scale (VAS and the outcomes were compared. Chi-squared and student t test were performed to evaluate differences between two groups. Results: Sixty patients were randomly divided into two groups (83.3% male. The mean age of patients was 31 ±0.7 years. While the onset of analgesia was significantly longer in the NSAB group, the mean total time of procedure was shorter than PSA (p<0.001. The NSAB group needed a shorter post-operative observation time (P<0.001. Both groups experienced equal pain relief before, during and after procedure (p>0.05. Conclusion: It seems that shorter post-operative monitoring time and consequently lesser total time of procedure, make nerve stimulator guided axillary block as an appropriate alternative for procedural sedation and analgesia in painless reduction of distal radius fractures in emergency department.
Tibia and radius bone geometry and volumetric density in obese compared to non-obese adolescents.
Leonard, Mary B; Zemel, Babette S; Wrotniak, Brian H; Klieger, Sarah B; Shults, Justine; Stallings, Virginia A; Stettler, Nicolas
2015-04-01
Childhood obesity is associated with biologic and behavioral characteristics that may impact bone mineral density (BMD) and structure. The objective was to determine the association between obesity and bone outcomes, independent of sexual and skeletal maturity, muscle area and strength, physical activity, calcium intake, biomarkers of inflammation, and vitamin D status. Tibia and radius peripheral quantitative CT scans were obtained in 91 obese (BMI>97th percentile) and 51 non-obese adolescents (BMI>5th and Tibia cortical section modulus and calf muscle area Z-scores were greater in obese participants (1.07 and 1.63, respectively, both pTibia and radius trabecular and cortical volumetric BMD did not differ significantly between groups. Calf muscle area and strength Z-scores, advanced skeletal maturity, and physical activity (by accelerometry) were positively associated with tibia cortical section modulus Z-scores (all ptibia section modulus Z-scores between obese and non-obese participants from 1.07 to 0.28. After multivariate adjustment for greater calf muscle area and strength Z-scores, advanced maturity, and less moderate to vigorous physical activity, tibia section modulus Z-scores were 0.32 (95% CI -0.18, 0.43, p=0.06) greater in obese, vs. non-obese participants. Radius cortical section modulus Z-scores were 0.45 greater (p=0.08) in obese vs. non-obese participants; this difference was attenuated to 0.14 with adjustment for advanced maturity. These findings suggest that greater tibia cortical section modulus in obese adolescents is attributable to advanced skeletal maturation and greater muscle area and strength, while less moderate to vigorous physical activities offset the positive effects of these covariates. The impact of obesity on cortical structure was greater at weight bearing sites.
Suzaku Observations of the Hydra A Cluster out to the Virial Radius
Sato, Takuya; Sasaki, Toru; Matsushita, Kyoko; Sakuma, Eri; Sato, Kosuke; Fujita, Yutaka; Okabe, Nobuhiro; Fukazawa, Yasushi; Ichikawa, Kazuya; Kawaharada, Madoka; Nakazawa, Kazuhiro; Ohashi, Takaya; Ota, Naomi; Takizawa, Motokazu; Tamura, Takayuki
2012-10-01
We report on Suzaku observations of the northern half of the Hydra A cluster out to ˜ 1.4 Mpc, reaching the virial radius. There are the first Suzaku observations of a medium-size (kT ˜ 3 keV) cluster out to the virial radius. Two observations were conducted, north-west and north-east offsets, which continue in a filament direction and a void direction of the large-scale structure of the Universe, respectively. The X-ray emission and distribution of galaxies elongate in the filament direction. The temperature profiles in the two directions are mostly consistent with each other within the error bars, and drop to 1.5 keV at 1.5 r500 . As observed by Suzaku in hot clusters, the entropy profile becomes flatter beyond r500 , in disagreement with the r1.1 relationship, which is expected from accretion shock heating models. When scaled with the average intracluster medium (ICM) temperature, the entropy profiles of clusters observed with Suzaku are universal, and do not depend on the system mass. The hydrostatic mass values in the void and filament directions are in good agreement, and the Navarro, Frenk, and White universal mass profile represents the hydrostatic mass distribution up to ˜ 2r500 . Beyond r500 , the ratio of the gas mass to the hydrostatic mass exceeds the result of the Wilkinson microwave anisotropy probe, and at r100 , these ratios in the filament and void directions reach 0.4 and 0.3, respectively. We discuss possible deviations from the hydrostatic equilibrium at cluster outskirts. We derived radial profiles of the gas-mass-to-light ratio and the iron-mass-to-light ratio out to the virial radius. Within r500 , the iron-mass-to-light ratio of the Hydra A cluster was compared with those in other clusters observed with Suzaku.
Giant cell tumors of lower end of the radius : Problems and solutions
Dhammi I
2005-01-01
Full Text Available Background: Giant cell tumors of bone are aggressive, potentially malignant lesions. Juxtaarticular giant cell tumours of lower end radius are common and present a special problem of reconstruction after tumor excision. Out of the various reconstructive procedures described, use of nonvascularised fibular autograft has been widely used with satisfactory functional results. Methods: Sixteen patients with a mean age of 20.2 years, with either Campanacci grade II or III histologically proven giant cell tumours of lower end radius were treated with wide excision and reconstruction with ipsilateral nonvascularised proximal fibular autograft. Host graft junction was fixed with intramedullary nail in 12 cases and DCP in last 4 cases. Wrist ligament reconstruction and fixation of the head of fibula with carpal bones using K-wires and primary cancellous iliac crest grafting at graft host junction with DCP was done in last 2 cases. Results: The follow up ranges from 2 - 5 years (mean 3.5 years. At last follow up, the average combined range of motion was 110° with range varying from 60-125°. The average grip strength was 39% in comparison to the contralateral side (range 21-88%. The average union time was 8 months (range 4-12 months. Sound union occurred in 5 months, where DCPs were used. There were 5 nonunions, one resorption of graft, 10 wrist subluxations (2 painful, one recurrence, 3 superficial infections, one wound dehiscence and one amputation. There was no case of graft fracture, metastasis, death or significant donor site morbidity. A total of 10 secondary procedures were required. Conclusions: Enbloc resection of giant cell tumours of lower end radius is a widely accepted method. Reconstruction with nonvascularised fibular graft, internal fixation with DCP with primary corticocancellous bone grafting with transfixation of the fibular head and wrist ligament reconstruction minimizes the problem and gives satisfactory functional results.
Responsiveness of EQ-5D in Patients With a Distal Radius Fracture.
Rundgren, Johanna; Enocson, Anders; Mellstrand Navarro, Cecilia; Bergström, Gunnar
2017-08-01
The EuroQol Group 5-Dimension (EQ-5D) questionnaire is frequently used as an outcome measure of general patient-reported health-related quality of life (HRQoL). We evaluated the internal and external responsiveness of EQ-5D (specifically EQ-5Dindex score) in patients with a surgically treated distal radius fracture. Within the context of a randomized controlled trial (RCT), 132 patients with a surgically treated distal radius fracture filled out EQ-5D and Patient-Rated Wrist Evaluation (PRWE-Swe) at baseline (preinjury state), and at 3 and 12 months. Internal responsiveness was evaluated by calculating mean change score and standardized response mean (SRM) of the EQ-5Dindex scores. External responsiveness was evaluated with PRWE-Swe as the external criterion. PRWE-Swe was used to define 4 subgroups of patients with different clinical outcomes. The ability of EQ-5Dindex change score to discriminate between these subgroups was analyzed with logistic regression, receiver operating characteristic (ROC) curves, and area under the ROC curves (AUROCs). Correlation analysis was made with Spearman's ρ test. The mean change in EQ-5Dindex score from baseline to the 3-month follow-up was -16.1 and from the 3- to the 12-month follow-up was 7.6. The corresponding SRMs were large (0.93) and small to moderate (0.47). Analysis of external responsiveness displayed odds ratios >1 and AUROCs between 0.70 and 0.76 in all 4 subgroups. The proportion of patients correctly classified into the 4 subgroups by the EQ-5Dindex change scores was 78% to 94%. Spearman's ρ was 0.35. EQ-5D displayed an overall acceptable to good responsiveness in patients with a distal radius fracture. It may thus be used as a measure of HRQoL in this patient group.
Vargaonkar Gauresh
2014-01-01
Objective:The rapid expansion of knowledge regarding the functional anatomy of hand and wrist,increasing functional demands of senior citizens and improved methodologies of achieving and maintaining anatomic restoration of distal radius fractures has generated a renewed interest in addressing these fractures in a more precise manner.The purpose of our study was to evaluate the difference in patients function among those treated by 1) closed reduction and Plaster of Paris cast,2) distractor application,or 3) open reduction and internal fixation with a volar plate,and to assess the treatment choice for each particular fracture type.Methods:A prospective study was carried out on 60 patients with fractures of the distal end radius.Fractures were classified according to the AO classification into type A (extra-articular),type B (partial articular) and type C (complete articular).After initial evaluation patients were taken up for either conservative or operative treatment and were followed up for two years.Results:Anatomical results were evaluated according to the Sarmiento's modification of Lindstrom Criteria,which showed that excellent results were more frequent with open reduction and internal fixation using the plating technique.Clinical and functional results were evaluated according to the demerit point system of Gartland and Werley with Sarmiento modification,which was revealed to relate with the type of treatment techniques.Conclusion:There is no customized solution for all the fractures of the distal radius.The choice of treatment should be based on the fracture type,the patient's characteristics,the patient's demands and the treating surgeon's experience and preference.
Liu, Xiong; Wu, Wei-dong; Fang, Ya-feng; Zhang, Mei-chao; Huang, Wen-hua
2014-01-01
To evaluate the postoperative stability of osteoporotic distal radius fractures fixed with distal locking screws with different length. A comminuted extra-articular dorsally unstable distal radius fracture, treated with volar locking plate system, was created. The 18 specimens were randomized into 3 groups based on distal locked screws with different length: Group A had unicortical screws with 50% length to the dorsal cortex. Group B had unicortical screws with 75% length to the dorsal cortex. Group C had bicortical screws. Axial compression and bending loads were imposed on the models before and after cycling testing as well as load to clinical and catastrophic failure. Minimum change in stiffness was observed before and after fatigue for all groups. The final stiffness to bending forces was statistically similar in all groups, but stiffness to axial compression was statistically significant different: Group A approached significance with respect to groups B and C (P = 0.017, 0.009), whereas stiffness in group B and C was statistically similar (P = 0.93). Load to clinical failure was significantly less for group A (456.54±78.59 N) compared with groups B (580.24±73.85 N) and C (591.07±38.40 N). Load to catastrophic failure was statistically similar between groups, but mean values for Group A were 18% less than means for Group C. The volar locking plate system fixed with unicortical locking screws with at least 75% length not only produced early stability for osteoporotic distal radius fractures, but also avoided extensor tendon complications due to dorsal screw protrusion.
Xiong Liu
Full Text Available To evaluate the postoperative stability of osteoporotic distal radius fractures fixed with distal locking screws with different length.A comminuted extra-articular dorsally unstable distal radius fracture, treated with volar locking plate system, was created. The 18 specimens were randomized into 3 groups based on distal locked screws with different length: Group A had unicortical screws with 50% length to the dorsal cortex. Group B had unicortical screws with 75% length to the dorsal cortex. Group C had bicortical screws. Axial compression and bending loads were imposed on the models before and after cycling testing as well as load to clinical and catastrophic failure.Minimum change in stiffness was observed before and after fatigue for all groups. The final stiffness to bending forces was statistically similar in all groups, but stiffness to axial compression was statistically significant different: Group A approached significance with respect to groups B and C (P = 0.017, 0.009, whereas stiffness in group B and C was statistically similar (P = 0.93. Load to clinical failure was significantly less for group A (456.54±78.59 N compared with groups B (580.24±73.85 N and C (591.07±38.40 N. Load to catastrophic failure was statistically similar between groups, but mean values for Group A were 18% less than means for Group C.The volar locking plate system fixed with unicortical locking screws with at least 75% length not only produced early stability for osteoporotic distal radius fractures, but also avoided extensor tendon complications due to dorsal screw protrusion.
Theoretical and observational constraints on the mass-radius relations of neutron stars
Boshkayev, Kuantay; Muccino, Marco
2016-01-01
We investigate theoretical and observational constraints on the mass-radius relations for neutron stars. For that purpose we consider the model of neutron stars taking into considerations strong, weak, electromagnetic and gravitational interactions in the equation of state and integrate the structure equations within the Hartle-Thorne formalism for rotating configurations. On the basis of the theoretical restrictions imposed by general relativity, mass-shedding and axisymmetric secular instabilities we calculate the upper and lower bounds for the parameters of neutron stars. Our theoretical calculations have been compared and contrasted with the observational constraints and as a result we show that the observational constraints favor stiff equations of state.
Missed radiative corrections in muon g-2 and proton charge radius measurements
Arbuzov Andrej
2016-01-01
Full Text Available QED radiative corrections to the muon anomalous magnetic moment and elastic electron-proton scattering are discussed. It is shown that a collective effect due to mutual interaction of muons within experimental conditions might provide a contribution to the observed muon magnetic moment. This effect is parameterized by an effective mean shift of muons off their mass shells. Higher order corrections to elastic electronproton at low energies are systematically treated within the leading and next-to-leading logarithmic approximation. The corrections are relevant for the modern experiments on proton form factor and charge radius definition.
Solid variant of aneurysmal bone cist on the distal extremity of the radius in a child.
Ferreira, Adriano Jander; de Almeida Leitão, Sebastião; Rocha, Murilo Antônio; Nascimento, Valdênia das Graças; Lima, Giovanni Bessa Pereira; de Meneses, Antonio Carlos Oliveira
2016-01-01
The solid variant of aneurismal bone cysts (ABC) is considered rare. It occurs with greater frequency in pediatric patients and in the tibia, femur, pelvis and humerus. We present a case of a metaphyseal lytic lesion on the distal extremity of the radius in a child whose radiograph was requested after low-energy trauma. The hypothesis of a pathological bone fracture secondary to an aneurysmal bone cyst was suggested. After biopsy, the child underwent intralesional excision without bone grafting and the histopathological findings were compatible with the solid variant of aneurysmal bone cyst.
Influence of stellar variability on the determination of the radius during a transit of an exoplanet
Désert J.-M.
2011-07-01
Full Text Available Stellar variability can affect the estimate of an exoplanet radius measured during a transit. We developed a transit light curve model which includes stellar spots. It appears that, if spectro-photometric technique is used, spots and faculae have to be considered to conclude on atmospheric detection and characterization. When using a model including spots, characterization of Hot-Jupiter atmosphere around active stars is possible with this technique, provided a signal to noise ratio up to 105. For Earth-size planets a long-term parallel photometric follow up monitoring the stellar activity is required to compensate the error due to the stellar variability.
Kauther, M D; Rummel, S; Hussmann, B; Lendemans, S; Nast-Kolb, D; Wedemeyer, C
2011-12-01
The cyr wheel is a modified gymnastic wheel with only one ring that can lead to extreme forces on the gymnast. We report on a distal radius shaft fracture (AO 22 A 2.1) and a fracture of the styloid process of the ulna that occurred after holding on to a slipping Cyr wheel and exposition to high pressure on the lower arm. The fracture was fixed by screws and a plate. © Georg Thieme Verlag KG Stuttgart · New York.
On the Bishop-Phelps-Bollobás Property for Numerical Radius
Sun Kwang Kim
2014-01-01
Full Text Available We study the Bishop-Phelps-Bollobás property for numerical radius (in short, BPBp-nu and find sufficient conditions for Banach spaces to ensure the BPBp-nu. Among other results, we show that L1μ-spaces have this property for every measure μ. On the other hand, we show that every infinite-dimensional separable Banach space can be renormed to fail the BPBp-nu. In particular, this shows that the Radon-Nikodým property (even reflexivity is not enough to get BPBp-nu.
The hadronic corrections to muonic hydrogen Lamb shift from ChPT and the proton radius
Peset, Clara [Grup de Física Teòrica, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona (Spain)
2016-01-22
We obtain a model independent expression for the muonic hydrogen Lamb shift. The leading hadronic effects are controlled by the chiral theory, which allows for their model independent determination. We give their complete expression including the pion and Delta particles. Out of this analysis and the experimental measurement of the muonic hydrogen Lamb shift we determine the electromagnetic proton radius: r{sub p} = 0.8412(15) fm. This number is at 6.8σ variance with respect to the CODATA value. The parametric control of the uncertainties allows us to obtain a model independent determination of the error, which is dominated by hadronic effects.
The Inclination, Pitch Angle and Forbidden Radius of Spiral Arms of PGC 35105
无
2006-01-01
We have studied some properties including surface brightness in the u, g,r, i, and z bands of the nearly face-on galaxy PGC 35105. By subtracting a model surface brightness distribution from the observed image we obtain the residual image that shows only the spiral arms freed from the contamination by the bulge. From this we measured the the inclination, pitch angle, and forbidden radius (identified with the innermost point of the arm) for each of the two arms; and that for each of the five observing bands. We found these three parameters are largely independent of the observing band.
Isotopic effects on non-linearity, molecular radius and intermolecular free length
Ranjan Dey; Arvind K Singh; N K Soni; B S Bisht; J D Pandey
2006-08-01
Computation of non-linearity parameter (/), molecular radius (rm) and intermolecular free length (f) for H2O, C6H6, C6H12, CH3OH, C2H5OH and their deuterium-substituted compounds have been carried out at four different temperatures, viz., 293.15, 303.15, 313.15 and 323.15 K. The aim of the investigation is an attempt to study the isotopic effects on the non-linearity parameter and the physicochemical properties of the liquids, which in turn has been used to study their effect on the intermolecular interactions produced thereof.
Reconstruction and Calibration of Small Radius Jets in the ATLAS Experiment for LHC Run 2
Loch, Peter; The ATLAS collaboration
2017-01-01
Small radius jets with R = 0.4 are standard tools in ATLAS for physics analysis. They are calibrated using a sequence of Monte Carlo simulation-derived calibrations and corrections followed by in-situ calibrations based on the transverse momentum balance between the probed jets and well-measured reference signals. In this talk the inputs to jet reconstruction in LHC Run 2 comprising calorimeter cell clusters, reconstructed charge particle tracks, and particle flow objects, are discussed together with the jet energy calibration scheme. Selected results from the performance of the procedure and the associated systematic uncertainties are presented.
[The thickness/radius ratio (t/r) in patients with dilated and hypertrophic cardiomyopathy].
Guadalajara, J F; Valenzuela, F; Martínez Sánchez, C; Huerta, D
1990-01-01
We studied 17 patients with cardiomyopathy (10 hypertrophic and 7 dilated). With two-dimensional echocardiography, we obtained a short axis view at the level of papillary muscle. We calculated the ratio between thickness (h), of ventricular wall and cavity's radius (r) in diastole and systole (h/r ratio). Hypertrophic cardiomyopathy has a high h/r ratio in diastole (inappropriate hypertrophy), hypercontractility and low and systolic wall stress. Dilated cardiomyopathy has a low diastolic h/r ratio (inadequate hypertrophy) with low contractility and elevated end-systolic, wall stress. We discuss the mechanisms and consequences of different patterns of hypertrophy on the ventricular performance.
Calculation of Effective Earth Radius and Point Refractivity Gradient in UAE
Abdulhadi Abu-Almal
2010-01-01
Full Text Available A large set of 14 years of reliable local radiosonde meteorological data, from 1990 to 2003, has been used to calculate the effective Earth radius and point refractivity gradient in the United Arab Emirates. The obtained values are used to investigate their impact on the design of microwave links. The cumulative distribution of the refractivity gradient in the first 65 meters above the ground surface, the monthly distribution for the median value of the k-factor, as well as their comparison with the ITU-maps are provided. Both experimental and global standard values are applied to specific link budget calculations.
Proton radius from electron-proton scattering and chiral perturbation theory
Horbatsch, Marko; Pineda, Antonio
2016-01-01
We determine the root-mean-square proton charge radius, $R_{\\rm p}$, from a fit to low-$Q^2$ electron-proton elastic scattering cross section data with the higher moments fixed (within uncertainties) to the values predicted by chiral perturbation theory. We obtain $R_{\\rm p}=0.844(12)$ fm. This number is perfectly consistent with the value obtained from muonic hydrogen analyses and disagrees with the CODATA value (based upon atomic hydrogen spectroscopy and electron-proton scattering determinations) by more than two standard deviations.
Absence of complete finite-Larmor-radius stabilization in extended MHD.
Zhu, P; Schnack, D D; Ebrahimi, F; Zweibel, E G; Suzuki, M; Hegna, C C; Sovinec, C R
2008-08-22
The dominant finite-Larmour-radius (FLR) stabilization effects on interchange instability can be retained by taking into account the ion gyroviscosity or the generalized Ohm's law in an extended MHD model. However, recent simulations and theoretical calculations indicate that complete FLR stabilization of the interchange mode may not be attainable by ion gyroviscosity or the two-fluid effect alone in the framework of extended MHD. For a class of plasma equilibria in certain finite-beta or nonisentropic regimes, the critical wave number for complete FLR stabilization tends toward infinity.
Alignment Compensation for Bending Radius in TI 2 Transfer Line Magnets
Weterings, W
2004-01-01
The optics file for the TI 2 transfer lines specifies the position of the bending magnets assuming that the beam enters and exists at the centre of the vacuum pipe. In order to disbribute the deflected beam evenly inside the vacuum tube, the alignment has to be compensated by moving the magnets half of the beam deflection away from the centre of the bending radius. In this note the saggitas of the various TI 2 magnets are calculated and the alignment displacements tabulated for future reference.
Alignment Compensation for Bending Radius in TT40 and TI 8 Transfer Line Magnets
Weterings, W
2003-01-01
The BEATCH file for the TI 8 transfer lines specifies the position of the bending magnets assuming that the beam enters and exits at the centre of the vacuum pipe. In order to distribute the deflected beam evenly inside the vacuum tube, the alignment has to be compensated by moving the magnets half of the beam deflection away from the centre of the bending radius. In this note the saggitas of the various TT40 and TI 8 magnets are calculated and the alignment displacements tabulated for future reference.
Fast polarization-state tracking scheme based on radius-directed linear Kalman filter.
Yang, Yanfu; Cao, Guoliang; Zhong, Kangping; Zhou, Xian; Yao, Yong; Lau, Alan Pak Tao; Lu, Chao
2015-07-27
We propose and experimentally demonstrate a fast polarization tracking scheme based on radius-directed linear Kalman filter. It has the advantages of fast convergence and is inherently insensitive to phase noise and frequency offset effects. The scheme is experimentally compared to conventional polarization tracking methods on the polarization rotation angular frequency. The results show that better tracking capability with more than one order of magnitude improvement is obtained in the cases of polarization multiplexed QPSK and 16QAM signals. The influences of the filter tuning parameters on tracking performance are also investigated in detail.
Influence of Surface Radius Curvature on Laser Plasma Propulsion with Ablation Water Propellant
Liang, Tian; Zheng, Zhiyuan; Zhang, Siqi; Tang, Weichong; Xiao, Ke; Liang, Wenfei; Gao, Lu; Gao, Hua
2016-10-01
The surface shape of liquid water is well controlled during nanosecond pulse laser ablation plasma propulsion. In this study, we measured the effect of the shape on the coupling coefficient and the specific impulse. We found that the coupling coefficient and specific impulse could be optimized by varying the surface convexity. Based on the analysis of the surface radius curvature, we demonstrate that the convex surface changes the laser focal positions to achieve high efficiency. supported by National Natural Science Foundation of China (No. 10905049) and Fundamental Research Funds for the Central Universities of China (Nos. 53200859165, 2562010050)
Jain, Shweta, E-mail: jshweta09@gmail.com; Sharma, Prerana [Department of Physics, Ujjain Engineering College, Ujjain, M.P.456010 (India); Chhajlani, R. K. [School of Studies in Physics, Vikram University Ujjain, M. P. - 456010 (India)
2015-07-31
The Jeans instability of self-gravitating quantum plasma is examined considering the effects of viscosity, finite Larmor radius (FLR) corrections and rotation. The analysis is done by normal mode analysis theory with the help of relevant linearized perturbation equations of the problem. The general dispersion relation is obtained using the quantum magneto hydrodynamic model. The modified condition of Jeans instability is obtained and the numerical calculations have been performed to show the effects of various parameters on the growth rate of Jeans instability.
Simulation analysis of minimum bending radius for lead frame copper alloys
Su, Juanhua; Shuguo, Jia; Fengzhang, Ren
2013-01-01
Copper alloy has a lot of excellent properties, so it becomes an important alloy for lead frame materials for the integrated circuit. The minimum bending radius of three different copper alloys (Cu-Fe-P, Cu-Ni-Si, Cu-Cr-Sn-Zn) for lead frame materials was analyzed by using finite element. Tensile tests for the three kinds of materials were done to obtain yield stress, ultimate strength and other parameters. The strain-hardening exponent n and normal anisotropy index r of the materials were ob...
Measurement of the Neutron Radius of 208Pb Through Parity-Violation in Electron Scattering
Abrahamyan, S; Albataineh, H; Aniol, K; Armstrong, D S; Armstrong, W; Averett, T; Babineau, B; Barbieri, A; Bellini, V; Beminiwattha, R; Benesch, J; Benmokhtar, F; Bielarski, T; Boeglin, W; Camsonne, A; Canan, M; Carter, P; Cates, G D; Chen, C; Chen, J -P; Hen, O; Cusanno, F; Dalton, M M; De Leo, R; de Jager, K; Deconinck, W; Decowski, P; Deng, X; Deur, A; Dutta, D; Etile, A; Flay, D; Franklin, G B; Friend, M; Frullani, S; Fuchey, E; Garibaldi, F; Gasser, E; Gilman, R; Giusa, A; Glamazdin, A; Gomez, J; Grames, J; Gu, C; Hansen, O; Hansknecht, J; Higinbotham, D W; Holmes, R S; Holmstrom, T; Horowitz, C J; Hoskins, J; Huang, J; Hyde, C E; Itard, F; Jen, C -M; Jensen, E; Jin, G; Johnston, S; Kelleher, A; Kliakhandler, K; King, P M; Kowalski, S; Kumar, K S; Leacock, J; Leckey, J; Lee, J H; LeRose, J J; Lindgren, R; Liyanage, N; Lubinsky, N; Mammei, J; Mammoliti, F; Margaziotis, D J; Markowitz, P; McCreary, A; McNulty, D; Mercado, L; Meziani, Z -E; Michaels, R W; Mihovilovic, M; Muangma, N; Muñoz-Camacho, C; Nanda, S; Nelyubin, V; Nuruzzaman, N; Oh, Y; Palmer, A; Parno, D; Paschke, K D; Phillips, S K; Poelker, B; Pomatsalyuk, R; Posik, M; Puckett, A J R; Quinn, B; Rakhman, A; Reimer, P E; Riordan, S; Rogan, P; Ron, G; Russo, G; Saenboonruang, K; Saha, A; Sawatzky, B; Shahinyan, A; Silwal, R; Sirca, S; Slifer, K; Solvignon, P; Souder, P A; Sperduto, M L; Subedi, R; Suleiman, R; Sulkosky, V; Sutera, C M; Tobias, W A; Troth, W; Urciuoli, G M; Waidyawansa, B; Wang, D; Wexler, J; Wilson, R; Wojtsekhowski, B; Yan, X; Yao, H; Ye, Y; Ye, Z; Yim, V; Zana, L; Zhan, X; Zhang, J; Zhang, Y; Zheng, X; Zhu, P
2012-01-01
We report the first measurement of the parity-violating asymmetry A_PV in the elastic scattering of polarized electrons from 208Pb. A_PV is sensitive to the radius of the neutron distribution (Rn). The result A_PV = 0.656 \\pm 0.060 (stat) \\pm 0.013 (syst) corresponds to a difference between the radii of the neutron and proton distributions Rn - Rp = 0.33 +0.16 -0.18 fm and provides the first electroweak observation of the neutron skin which is expected in a heavy, neutron-rich nucleus.
Flat currents modulo p in metric spaces and filling radius inequalities
Ambrosio, Luigi
2010-01-01
We adapt the theory of currents in metric spaces, as developed by the first-mentioned author in collaboration with B. Kirchheim, to currents with coefficients in Z_p. We obtain isoperimetric inequalities mod(p) in Banach spaces and we apply these inequalities to provide a proof of Gromov's filling radius inequality which applies also to nonorientable manifolds. With this goal in mind, we use the Ekeland principle to provide quasi-minimizers of the mass mod(p) in the homology class, and use the isoperimetric inequality to give lower bounds on the growth of their mass in balls.
Spadin, F.; Marti, Dominik; Hidalgo-Staub, R.
2015-01-01
Stalagmites are natural archives containing detailed information on continental climate variability of the past. Microthermometric measurements of fluid inclusion homogenisation temperatures allow determination of stalagmite formation temperatures by measuring the radius of stable laser-induced v......Stalagmites are natural archives containing detailed information on continental climate variability of the past. Microthermometric measurements of fluid inclusion homogenisation temperatures allow determination of stalagmite formation temperatures by measuring the radius of stable laser......-induced vapour bubbles inside the inclusions. A reliable method for precisely measuring the radius of vapour bubbles is presented. The method is applied to stalagmite samples for which the formation temperature is known. An assessment of the bubble radius measurement accuracy and how this error influences...
Equivalent pore radius and velocity of elastic waves in shale. Skjold Flank-1 Well, Danish North Sea
Mbia, Ernest Ncha; Fabricius, Ida Lykke; Oji, Collins O.
2013-01-01
Equivalent pore radius links permeability and porosity of a porous medium. This property can be calculated from specific surface and porosity data measured in the laboratory. We can obtain porosity information from logging data but specific surface information can only be obtained from laboratory...... experiments on cuttings or core samples. In this study we demonstrate that elastic moduli as calculated from bulk density and velocity of elastic waves relate to equivalent pore radius of the studied shale intervals. This relationship establishes the possibility of calculating equivalent pore radius from...... and BET specific surface were obtained from these samples using kaolinite and smectite as reference. The cuttings samples were also characterized with respect to mineralogical composition, content of organic carbon and cation exchange capacity.Equivalent pore radius was calculated from porosity and BET...
The Transit Light Curve Project. IX. Evidence for a Smaller Radius of the Exoplanet XO-3b
Winn, Joshua N; Torres, Guillermo; McCullough, Peter; Johns-Krull, Christopher M; Latham, David W; Shporer, Avi; Mazeh, Tsevi; Garcia-Melendo, Enrique; Foote, Cindy; Esquerdo, Gil; Everett, Mark
2008-01-01
We present photometry of 13 transits of XO-3b, a massive transiting planet on an eccentric orbit. Previous data led to two inconsistent estimates of the planetary radius. Our data strongly favor the smaller radius, with increased precision: R_p = 1.217 +/- 0.073 R_Jup. A conflict remains between the mean stellar density determined from the light curve, and the stellar surface gravity determined from the shapes of spectral lines. We argue the light curve should take precedence, and revise the system parameters accordingly. The planetary radius is about 1 sigma larger than the theoretical radius for a hydrogen-helium planet of the given mass and insolation. To help in planning future observations, we provide refined transit and occultation ephemerides.
Lochmüller, Eva‐Maria; Lill, Christoph A; Kuhn, Volker; Schneider, Erich; Eckstein, Felix
2002-01-01
This study comprehensively analyzes the ability of site‐specific and nonsite‐specific clinical densitometric techniques for predicting mechanical strength of the distal radius in different loading configurations...
Arthroscopic knotless anchor repair of triangular fibrocartilage in distal radius fracture.
García-Ruano, Á A; Najarro-Cid, F; Jiménez-Martín, A; Gómez de los Infantes-Troncoso, J G; Sicre-González, M
2015-01-01
Lesions of triangular fibrocartilage (TFC) are associated with distal radioulnar joint instability. Arthroscopic treatment of these lesions improves functional outcome of affected patients. The aim of the present work is to evaluate functional and occupational outcome of TCF repair using an arthroscopic knotless anchor device in patients with associated distal radius fracture. An observational, descriptive study was carried out between November 2011 and January 2014 including 21 patients with distal radius fracture and Palmer 1B lesions of TCF (Atzei class 2 and 3) that were treated by arthroscopic knotless anchor (PopLok® 2,8mm, ConMed, USA). Mean follow-up was 18 months. Functional (Mayo Wrist Score) and occupational outcome results were analyzed. Mean age of the group was 43.0±8.8 years, with 19% of the patients being female. There was an associated scapholunate lesion in 5 cases. Functional results reached a mean of 83.4±16.1 points onMayo Wrist Score. Mean sick-leave time was 153.16±48.5 days. Complete occupational reintegration was reached in 89.5% of cases. There were no postoperative complications. Arthroscopic knotless anchor repair of 1B TFC tears is a minimally invasive method of treatment that improves tension of fixation, avoiding subsequent loosen, in our experience, with few complications and good functional and occupational results. Copyright © 2014 SECOT. Published by Elsevier Espana. All rights reserved.
James, Boblee
2016-01-01
Monteggia fracture constitutes about 5-10% of the forearm fractures. Monteggia fracture by definition is proximal ulnar fracture with disruption of proximal radioulnar joint. Bado classified Monteggia fracture dislocation into four types and Jupiter subclassified type II Bado’s fractures into four types. The associated injury in the form of distal radial fractures and distal humerus fractures are rare though many cases of distal radial physeal injuries have been reported in paediatric population. Hereby we report a rare association of type IIA Monteggia fracture dislocation with ipsilateral distal radius fracture in an adult patient. This case report also highlights on proper examination and full length radiographs of forearm to avoid missing injury at wrist in cases of elbow injuries. Management of such complex injuries included open reduction and internal fixation of olecronon fracture, distal radius fracture and radial head resection. Functional outcome at six months was good at wrist whereas at elbow, stiffness was a major concern with elbow range of movement from 40°-110°. PMID:27656518
Design-Optimization and Material Selection for a Proximal Radius Fracture-Fixation Implant
Grujicic, M.; Xie, X.; Arakere, G.; Grujicic, A.; Wagner, D. W.; Vallejo, A.
2010-11-01
The problem of optimal size, shape, and placement of a proximal radius-fracture fixation-plate is addressed computationally using a combined finite-element/design-optimization procedure. To expand the set of physiological loading conditions experienced by the implant during normal everyday activities of the patient, beyond those typically covered by the pre-clinical implant-evaluation testing procedures, the case of a wheel-chair push exertion is considered. Toward that end, a musculoskeletal multi-body inverse-dynamics analysis is carried out of a human propelling a wheelchair. The results obtained are used as input to a finite-element structural analysis for evaluation of the maximum stress and fatigue life of the parametrically defined implant design. While optimizing the design of the radius-fracture fixation-plate, realistic functional requirements pertaining to the attainment of the required level of the devise safety factor and longevity/lifecycle were considered. It is argued that the type of analyses employed in the present work should be: (a) used to complement the standard experimental pre-clinical implant-evaluation tests (the tests which normally include a limited number of daily-living physiological loading conditions and which rely on single pass/fail outcomes/decisions with respect to a set of lower-bound implant-performance criteria) and (b) integrated early in the implant design and material/manufacturing-route selection process.
The semi-inclusive jet function in SCET and small radius resummation for inclusive jet production
Kang, Zhong-Bo; Vitev, Ivan
2016-01-01
We introduce a new kind of jet function: the semi-inclusive jet function $J_i(z, \\omega_J, \\mu)$, which describes how a parton $i$ is transformed into a jet with a jet radius $R$ and energy fraction $z = \\omega_J/\\omega$, with $\\omega_J$ and $\\omega$ being the large light-cone momentum component of the jet and the corresponding parton $i$ that initiates the jet, respectively. Within Soft Collinear Effective Theory (SCET), we calculate both $J_q(z, \\omega_J, \\mu)$ and $J_g(z, \\omega_J, \\mu)$ to the next-to-leading order (NLO), and for both cone and anti-k$_{\\rm T}$ algorithms. We demonstrate that the renormalization group (RG) equations of $J_i(z, \\omega_J, \\mu)$ follow exactly the usual DGLAP evolution, which can be used to perform the $\\ln R$ resummation for {\\it inclusive} jet cross sections with a small jet radius $R$. We clarify the difference between our RG equations of $J_i(z, \\omega_J, \\mu)$ and those of so-called unmeasured jet functions $J_i(\\omega_J, \\mu)$, widely used in SCET for {\\it exclusive} je...
de Thomaz, A A; Almeida, D B; Pelegati, V B; Carvalho, H F; Cesar, C L
2015-03-19
One of the most important properties of quantum dots (QDs) is their size. Their size will determine optical properties and in a colloidal medium their range of interaction. The most common techniques used to measure QD size are transmission electron microscopy (TEM) and X-ray diffraction. However, these techniques demand the sample to be dried and under a vacuum. This way any hydrodynamic information is excluded and the preparation process may alter even the size of the QDs. Fluorescence correlation spectroscopy (FCS) is an optical technique with single molecule sensitivity capable of extracting the hydrodynamic radius (HR) of the QDs. The main drawback of FCS is the blinking phenomenon that alters the correlation function implicating in a QD apparent size smaller than it really is. In this work, we developed a method to exclude blinking of the FCS and measured the HR of colloidal QDs. We compared our results with TEM images, and the HR obtained by FCS is higher than the radius measured by TEM. We attribute this difference to the cap layer of the QD that cannot be seen in the TEM images.
The Low-Luminosity End of the Radius-Luminosity Relationship for Active Galactic Nuclei
Bentz, Misty C; Grier, Catherine J; Barth, Aaron J; Peterson, Bradley M; Vestergaard, Marianne; Bennert, Vardha N; Canalizo, Gabriela; De Rosa, Gisella; Filippenko, Alexei V; Gates, Elinor L; Greene, Jenny E; Li, Weidong; Malkan, Matthew A; Pogge, Richard W; Stern, Daniel; Treu, Tommaso; Woo, Jong-Hak
2013-01-01
We present an updated and revised analysis of the relationship between the Hbeta broad-line region (BLR) radius and the luminosity of the active galactic nucleus (AGN). Specifically, we have carried out two-dimensional surface brightness decompositions of the host galaxies of 9 new AGNs imaged with the Hubble Space Telescope Wide Field Camera 3. The surface brightness decompositions allow us to create "AGN-free" images of the galaxies, from which we measure the starlight contribution to the optical luminosity measured through the ground-based spectroscopic aperture. We also incorporate 20 new reverberation-mapping measurements of the Hbeta time lag, which is assumed to yield the average Hbeta BLR radius. The final sample includes 41 AGNs covering four orders of magnitude in luminosity. The additions and updates incorporated here primarily affect the low-luminosity end of the R-L relationship. The best fit to the relationship using a Bayesian analysis finds a slope of alpha = 0.533 (+0.035/-0.033), consistent ...
The Lick AGN Monitoring Project: Alternate Routes to a Broad-line Region Radius
Greene, Jenny E; Barth, Aaron J; Bennert, Vardha N; Bentz, Misty C; Filippenko, Alexei V; Gates, Elinor; Malkan, Matthew A; Treu, Tommaso; Walsh, Jonelle L; Woo, Jong-Hak
2010-01-01
It is now possible to estimate black hole masses across cosmic time, using broad emission lines in active galaxies. This technique informs our views of how galaxies and their central black holes coevolve. Unfortunately, there are many outstanding uncertainties associated with these "virial" mass estimates. One of these comes from using the accretion luminosity to infer a size for the broad-line region. Incorporating the new sample of low-luminosity active galaxies from our recent monitoring campaign at Lick Observatory, we recalibrate the radius-luminosity relation with tracers of the accretion luminosity other than the optical continuum. We find that the radius of the broad-line region scales as the square root of the X-ray and Hbeta luminosities, in agreement with recent optical studies. On the other hand, the scaling appears to be marginally steeper with narrow-line luminosities. This is consistent with a previously observed decrease in the ratio of narrow-line to X-ray luminosity with increasing total lum...