bluuebunny/crossref_metadata_2025 huggingface dataset:
Measuring g Using a Magnetic Pendulum and Telephone Pickup
Authors: Sinacore J. , Takai H.
Published: September 2010

The simple pendulum has long been used to measure g, the acceleration due to gravity, with a precision of a few percent. Achieving agreement with the accepted value of less than 1% is feasible in the high school laboratory, though it requires some care.1 The precision of the measurement is bound by how accurately the period and the pendulum length are determined. To improve on the period measurement, we have developed a simple and inexpensive method using a magnet and telephone pickup.2
Tutorials in Introductory Physics: The Pain and the Gain
Authors: Cruz Émerson , O'Shea Brian , Schaffenberger Werner , Wolf Steven , Kortemeyer Gerd
Published: September 2010

In an introductory physics sequence with a large enrollment of premedical students, traditional recitation sessions were replaced by Tutorials in Introductory Physics, developed by the Physics Education Group at the University of Washington. Initially, summative test scores (as well as FCI scores) dramatically increased, but so did student complaints and workload. Both effects decreased over time. The paper discusses issues that instructors should consider when contemplating implementation of the tutorials.
Experiments with Fluorescent Lamps
Authors: Kraftmakher Yaakov
Published: September 2010

The experiments described below show the irradiance and illuminance spectra of two fluorescent lamps in relation to their color temperatures, and the efficacy in comparison to that of an incandescent lamp. Spectra of “warm white” and “cool daylight” fluorescent lamps are demonstrated.
A Year Without Paper: Tablet Computers in the Classroom
Authors: Fons John
Published: September 2010

Students can be seen throughout any campus in America carrying their cell phones, laptop computers, and iPhones. I've seen a tremendous increase in the student use of laptop computers during lectures and students often ask for electronic copies of lectures rather than printed versions. In an attempt to adapt to my students' increasingly technology-driven lifestyle, I issued a tablet computer to all of my students, and for a year all course materials were digital, with no distribution of paper.
Impeding
Xist
Expression from the Active X Chromosome Improves Mouse Somatic Cell Nuclear Transfer
Authors: Inoue Kimiko , Kohda Takashi , Sugimoto Michihiko , Sado Takashi , Ogonuki Narumi , Matoba Shogo , Shiura Hirosuke , Ikeda Rieko , Mochida Keiji , Fujii Takashi , Sawai Ken , Otte Arie P. , Tian X. Cindy , Yang Xiangzhong , Ishino Fumitoshi , Abe Kuniya , Ogura Atsuo
Published: September 2010

Cloning Futures

Cloning mammals by somatic cell nuclear transfer is a technique with many potential applications in regenerative medicine, agriculture, and pharmaceutics; however, it is inefficient because of the incidence of aberrant genomic reprogramming.

Inoue
et al.

(p.
496
, published online 16 September) found that the gene product of
Xist
, which normally inactivates one of the two X chromosomes in females, was unexpectedly expressed ectopically from active X chromosomes in cloned mice. When
Xist
was deleted from the mice, gene expression returned to normal and the efficiency of somatic cell nuclear transfer increased about ninefold, offering promise for future nuclear transfer technology.
THE 3D SPIN GEOMETRY OF THE QUANTUM TWO-SPHERE
Authors: BRAIN SIMON , LANDI GIOVANNI
Published: September 2010

We study a three-dimensional differential calculus [Formula: see text] on the standard Podleś quantum two-sphere [Formula: see text], coming from the Woronowicz 4D+ differential calculus on the quantum group SU q(2). We use a frame bundle approach to give an explicit description of [Formula: see text] and its associated spin geometry in terms of a natural spectral triple over [Formula: see text]. We equip this spectral triple with a real structure for which the commutant property and the first order condition are satisfied up to infinitesimals of arbitrary order.
GROWTH AND CHARACTERIZATION OF CdS AND CdS:Ag LUMINESCENT QUANTUM DOTS DISPERSED IN SOLUTION
Authors: YOUSEFI M. H. , ABDOLHOSSEINZADEH A. A. , FALLAH H. R. , KHOSRAVI A. A.
Published: September 2010

A fast-chemically capping method in aqueous solution was developed to synthesize CdS and CdS : Ag luminescent nanoparticles and particles with sizes between 2–4 nm. The achieving of well-dispersed and narrow-sized particles in colloidal solution and also, high stability of them using mercaptoethanol (ME) as a capping agent was established. Quantum confinement effect was observed in UV-vis absorption as well as in PL spectra. PL spectroscopy also showed green emission and Ag dopants caused a faster energy transfer between CdS inter-bands. XRD patterns exhibited that both cubic and hexagonal phases exist in solutions. Ultimately, TEM images captured from QDs displayed the shapes of nanoclusters which are almost spherical.
STATISTICS OF A FREE SINGLE QUANTUM PARTICLE AT A FINITE TEMPERATURE
Authors: PENG JIAN-PING
Published: September 2010

We present a model to study the statistics of a single structureless quantum particle freely moving in a space at a finite temperature. It is shown that the quantum particle, in response to the temperature, can exchange energy with its environment in the form of heat transfer. The underlying mechanism is diffraction at the edge of the wavefront of its matter wave. The expressions of energy and entropy of the particle are obtained for the irreversible process.
THE SUPERFLUID PHASES OF LIQUID 3He: BCS THEORY
Authors: LEGGETT A. J.
Published: September 2010

Following the success of the original BCS theory as applied to superconductivity in metals, it was suggested that the phenomenon of Cooper pairing might also occur in liquid 3- He , though unlike the metallic case the pairs would most likely form in an anisotropic state, and would then lead in this neutral system to superfluidity. However, what had not been anticipated was the richness of the phenomena which would be revealed by the experiments of 1972. In the first place, even in a zero magnetic field there is not one but two superfluid phases, and the explanation of this involves ideas concerning "spin fluctuation feedback" which have no obvious analog in metals. Secondly, the anisotropic nature of the pair wave function, which in the case of the B phase is quite subtle, and the fact that the orientation must be the same for all the pairs, leads to a number of qualitatively new effects, in particular to a spectacular amplification of ultra-weak interactions seen most dramatically in the NMR behavior. In this chapter I review the application of BCS theory to superfluid 3- He with emphasis on these novel features.
THE SYSTEMATIC BEHAVIOR IN THE FRAGMENTS OF THE CALCIUM ISOTOPES PROJECTILE FRAGMENTATION
Authors: MA CHUN-WANG , WEI HUI-LING , LI YU-QI
Published: September 2010

We have calculated the cross sections of the fragments produced in the projectile fragmentation of the even 36–52 Ca isotopes using the statistical abrasion-ablation model. The isospin effect in the projectile fragmentation are studied by investigating the peak positions and the widths of the fragment isotopic cross section distributions. The peak positions of the fragments isotopic cross section distributions have good linear correlation to the Z of the fragments and the correlations are fitted using the linear function. The correlations between slopes b and the binding energies of the neutron ( S n) of the projectile nuclei, the differences between the binding energies of the neutron and proton( S n- S p) of the projectile nuclei and the neutron-skin thickness (δnp) are studied. It is found that b and δnp has a good linear correlation for the neutron-rich projectile nuclei.
STATISTICAL AND DYNAMICAL ASPECTS IN THE DECAY OF HOT NEUTRON-RICH NUCLEI
Authors: VESELSKÝ M. , SOULIOTIS G. A. , KEKSIS A. L. , SHETTY D. V. , JANDEL M. , YENNELLO S. J. , WANG K. , MA Y. G.
Published: September 2010

A signal of isospin-asymmetric phase transition in the evolution of chemical potential is observed in hot quasi-projectiles produced in the reactions 40,48 Ca + 27 Al confirming an analogous observation in the lighter quasi-projectiles observed in the reaction 28 Si + 112,124 Sn .1 With increasing mass, the properties of hot quasi-projectiles become increasingly influenced by secondary emission. Thermodynamical observables exhibit no sensitivity to a different number of missing neutrons in the two reactions 40,48 Ca + 27 Al and provide a signal of dynamical emission of neutrons, which can be related to a very neutron-rich low-density region (neck) between the projectile and target.
ISOVECTOR AND SPIN-ISOVECTOR SYMMETRY ENERGIES FROM POLARIZABILITIES
Authors: BRAGHIN FÁBIO L.
Published: September 2010

The momentum dependence of the nuclear matter isovector symmetry energy coefficient [Formula: see text] is presented in the framework of the nuclear matter polarizability with Skyrme interactions, as worked out in Refs. 1, 2. A slightly more complete account is presented for the spin-isovector symmetry energy [Formula: see text] as function of the temperature and momentum exchange and it is found to have a quite similar behavior to the isovector one [Formula: see text]. The variation of [Formula: see text] with temperature is quite soft and decreasing whereas the dependence on exchanged momentum can make [Formula: see text] to be close to zero, although it does not reach negative values.
ENTRANCE CHANNEL EFFECT AND FUSION CROSS SECTIONS IN THE SYNTHESIS OF HEAVY AND SUPERHEAVY NUCLEI
Authors: DU SAI-SAI , ZHANG FENG-SHOU
Published: September 2010

The entrance channel effect, mainly involved the mass asymmetry, the neutron-excess and the collision orientation of the combined system, are presented by summarizing the recent theoretical results about the fusion reactions leading to the same compound nuclei and the neutron-rich fusion reactions in the synthesis of heavy and superheavy nuclei through various models. It is concluded that the system with large mass asymmetry and neutron-rich nuclear reactions is favorable for the compound nucleus formation.
PROBING NUCLEAR FRICTION WITH γ RAYS
Authors: YE WEI , WU FENG
Published: September 2010

We study the variation of the post-saddle giant dipole resonance (GDR) γ-ray multiplicity associated with the fission of the heavy nuclei 240 Cf , 246 Cf , 252 Cf and 240 U with the post-saddle friction strength (β) in the framework of a Langevin model. Calculations show the emitted post-saddle γ emission becomes less sensitive to β with increasing isospin of the the system, and the sensitivity almost disappears for the case of 240 U . We suggest that to accurately obtain information of the post-saddle friction strength by measuring pre-scission GDR γ-ray multiplicities, it is optimal to choose among the various compound systems those with low isospin.
DETERMINING THE SPECIAL ORIENTATIONS IN DEFORMED 238U + 238U COLLISIONS AT CSR
Authors: WU KEJUN , LIU FENG
Published: September 2010

In this paper we report the different orientations effect on the high-density matter in deformed UU collisions at CSR energy. ART model is used in our analysis. We have tested and developed two measurements, the forward neutron multiplicity and nuclear stopping, which permit us to select the special UU collisions with extended high-density phase.
CONSTRAINTS ON THE DENSITY DEPENDENCE OF THE SYMMETRY ENERGY
Authors: TSANG M. B. , ZHANG YINGXUN , DANIELEWICZ P. , FAMIANO M. , LI ZHUXIA , LYNCH W. G. , SUN Z. Y. , AMORINI F. , ANDRONENKO L. , ANDRONENKO M. , CARDELLA G. , CHATTERJE M. , DINH P. , GALICHET E. , HUA H. , LAGUIDARA E. , LANZALONE G. , LIU H. , LU F. , MAIOLINO C. , PAGANO A. , PIANTELLI S. , PAPA M. , PIRRONE S. , POLITI G. , PORTO F. , RIZZO F. , RUSSOTTO P. , SANTONOCITO D. , VERDE G.
Published: September 2010

Collisions involving 112 Sn and 124 Sn nuclei have been calculated with the ImQMD transport model in order to place constraints on the density dependences of the nuclear symmetry energy. Consistent constraints on the symmetry energy at sub-saturation density have been obtained by comparing these transport calculations to measurements of isospin diffusion and to the ratios of neutron and proton spectra. New isospin diffusion results from E/A = 35 MeV are also presented.
TRITON-3HE RELATIVE AND DIFFERENTIAL FLOWS AND THE HIGH DENSITY BEHAVIOR OF NUCLEAR SYMMETRY ENERGY
Authors: YONG GAO-CHAN , LI BAO-AN , CHEN LIE-WEN
Published: September 2010

Using a transport model coupled with a phase-space coalescence after-burner we study the triton-3 He relative and differential transverse flows in semi-central 132 Sn + 124 Sn reactions at a beam energy of 400 MeV/nucleon. We find that the triton-3 He pairs carry interesting information about the density dependence of the nuclear symmetry energy. The t -3 He relative flow can be used as a particularly powerful probe of the high-density behavior of the nuclear symmetry energy.
THE SYMMETRY ENERGY IN NUCLEAR REACTIONS
Authors: TRAUTMANN W. , BIANCHIN S. , BOTVINA A. S. , LE FÈVRE A. , LEIFELS Y. , SFIENTI C. , BUYUKCIZMECI N. , OGUL R. , MISHUSTIN I.N. , CHARTIER M. , WU P.Z. , LEMMON R.C. , LI Q. , ŁUKASIK J. , PAWŁOWSKI P. , PAGANO A. , RUSSOTTO P. , THE ALADIN COLLABORATION
Published: September 2010

New results for the strength of the symmetry energy are presented which illustrate the complementary aspects encountered in reactions probing nuclear densities below and above saturation. A systematic study of isotopic effects in spectator fragmentation was performed at the ALADIN spectrometer with 124 Sn primary and 107 Sn and 124 La secondary beams of 600 MeV/nucleon incident energy. The analysis within the Statistical Fragmentation Model shows that the symmetry-term coefficient entering the liquid-drop description of the emerging fragments decreases significantly as the multiplicity of fragments and light particles from the disintegration of the produced spectator systems increases. Higher densities were probed in the FOPI/LAND study of nucleon and light-particle flows in central and mid-peripheral collisions of 197 Au +197 Au nuclei at 400 MeV/nucleon incident energy. From the comparison of the measured neutron and hydrogen squeeze-out ratios with predictions of the UrQMD model a moderately soft symmetry term with a density dependence of the potential term proportional to (ρ/ρ0)γ with γ = 0.9 ± 0.3 is favored.
PROBING THE SYMMETRY ENERGY AT HIGH BARYON DENSITY WITH HEAVY ION COLLISIONS
Authors: GRECO V. , COLONNA M. , DI TORO M. , WOLTER H. H.
Published: September 2010

The nuclear symmetry energy at densities above saturation density (ρ0 ~ 0.16fm-3) is poorly constrained theoretically and very few relevant experimental data exist. Its study is possible through Heavy Ion Collisions (HIC) at energies E/A > 200 MeV , particularly with beams of neutron-rich radioactive nuclei. The energy range implies that the momentum dependence of the isospin fields, i.e. the difference of the effective masses on protons and neutrons, also has to be investigated before a safe constraint on E sym (ρ) is possible. We discuss the several observables which have been suggested, like n/p emission and their collective flows and the ratio of meson yields with different isospin projection, π-/π+ and K0/K+. We point out several physical mechanisms that should be included in the theoretical models to allow a direct comparison to the more precise experiments which will be able to distinguish the isospin projection of the detected particles: CSR/Lanzhou, FAIR/GSI, RIBF/RIKEN, FRIB/MSU.
INCOMPRESSIBILITY OF ASYMMETRIC NUCLEAR MATTER
Authors: CHEN LIE-WEN , CAI BAO-JUN , SHEN CHUN , KO CHE MING , XU JUN , LI BAO-AN
Published: September 2010

Using an isospin- and momentum-dependent modified Gogny (MDI) interaction, the Skyrme-Hartree-Fock (SHF) approach, and a phenomenological modified Skyrme-like (MSL) model, we have studied the incompressibility K sat (δ) of isospin asymmetric nuclear matter at its saturation density. Our results show that in the expansion of K sat (δ) in powers of isospin asymmetry δ, i.e., K sat (δ) = K0 + K sat ,2δ2 + K sat ,4δ4 + O(δ6), the magnitude of the 4th-order K sat ,4 parameter is generally small. The 2nd-order K sat ,2 parameter thus essentially characterizes the isospin dependence of the incompressibility of asymmetric nuclear matter at saturation density. Furthermore, the K sat ,2 can be expressed as [Formula: see text] in terms of the slope parameter L and the curvature parameter K sym of the symmetry energy and the third-order derivative parameter J0 of the energy of symmetric nuclear matter at saturation density, and we find the higher order J0 contribution to K sat ,2 generally cannot be neglected. Also, we have found a linear correlation between K sym and L as well as between J0/K0 and K0. Using these correlations together with the empirical constraints on K0 and L, the nuclear symmetry energy E sym (ρ0) at normal nuclear density, and the nucleon effective mass, we have obtained an estimated value of K sat ,2 = -370 ± 120 MeV for the 2nd-order parameter in the isospin asymmetry expansion of the incompressibility of asymmetric nuclear matter at its saturation density.
PROBING THE SYMMETRY ENERGY AT SUPRA-SATURATION DENSITIES FROM PION EMISSION IN HEAVY-ION COLLISIONS
Authors: FENG ZHAO-QING , JIN GEN-MING
Published: September 2010

Within the framework of the improved isospin dependent quantum molecular dynamics (ImIQMD) model, the emission of pion in heavy-ion collisions in the region 1 A GeV as a probe of nuclear symmetry energy at supra-saturation densities is investigated systematically, in which the pion is considered to be mainly produced by the decay of resonances Δ(1232) and N *(1440). The π-/π+ yields are calculated for selected Skyrme parameters SkP, SLy6, Ska and SIII, and also for the cases of different stiffness of symmetry energy with the parameter SLy6. Preliminary results compared with the measured data by the FOPI collaboration favor a hard symmetry energy of the potential term proportional to (ρ/ρ0)γs with γs = 2.
IMPRINTS OF THE NUCLEAR SYMMETRY ENERGY ON GRAVITATIONAL WAVES FROM DEFORMED PULSARS
Authors: LI BAO-AN , KRASTEV PLAMEN G.
Published: September 2010

The density dependence of nuclear symmetry energy is a critical input for understanding many interesting phenomena in astrophysics and cosmology. We report here effects of the nuclear symmetry energy partially constrained by terrestrial laboratory experiments on the strength of gravitational waves (GWs) from deformed pulsars at both low and high rotational frequencies.
TRANSITION DENSITY AND PRESSURE AT THE INNER EDGE OF NEUTRON STAR CRUSTS
Authors: XU JUN , KO CHE MING , CHEN LIE-WEN , LI BAO-AN , MA HONG-RU
Published: September 2010

Using the nuclear symmetry energy that has been recently constrained by the isospin diffusion data in intermediate-energy heavy ion collisions, we have studied the transition density and pressure at the inner edge of neutron star crusts, and they are found to be 0.040 fm -3 ≤ ρt ≤ 0.065 fm -3 and 0.01 MeV / fm 3 ≤ Pt ≤ 0.26 MeV / fm 3, respectively, in both the dynamical and thermodynamical approaches. We have also found that the widely used parabolic approximation to the equation of state of asymmetric nuclear matter gives significantly higher values of core-crust transition density and pressure, especially for stiff symmetry energies. With these newly determined transition density and pressure, we have obtained an improved relation between the mass and radius of neutron stars.
EFFECTS OF THE NUCLEAR SYMMETRY ENERGY ON GRAVITATIONAL WAVES FROM THE AXIAL W-MODES OF ISOLATED NEUTRON STARS
Authors: WEN DE-HUA , LI BAO-AN , KRASTEV PLAMEN G.
Published: September 2010

The frequencies and damping times of the axial w-mode oscillations of neutron stars are investigated using a nuclear equation of state (EOS) partially constrained by the available terrestrial laboratory data. It is found that the nuclear symmetry energy E sym (ρ), especially its high density behavior, plays an important role in determining both the eigen-frequencies and the damping times of these oscillations.
CONSISTENT THREE-BODY FORCE WITH BONN B POTENTIAL AND NEUTRON STAR STRUCTURE
Authors: LI Z. H. , LOMBARDO U. , SCHULZE H.-J. , ZUO W.
Published: September 2010

Microscopic three-nucleon force consistent with the Bonn B two-nucleon potential is constructed, which includes Δ(1232), Roper, and nucleon-antinucleon excitation contributions. Recent results for the choice of the meson parameters are discussed. The forces are used in Brueckner calculations and the saturation properties of nuclear matter are determined. At the high densities, the nuclear equation of state and the symmetry energy are calculated. The corresponding neutron star mass-radius relations are presented.
RECENT ADVANCES IN THE THEORY OF NUCLEAR FORCES AND ITS RELEVANCE FOR THE MICROSCOPIC APPROACH TO DENSE MATTER
Authors: MACHLEIDT R.
Published: September 2010

The theory of nuclear forces has made great progress since the turn of the millenium using the framework of chiral effective field theory (ChEFT). The advantage of this approach, which was originally proposed by Weinberg, is that it has a firm basis in quantum-chromodynamics and allows for quantitative calculations. Moreover, this theory generates two-nucleon forces (2NF) and many-body forces on an equal footing and provides an explanation for the empirically known fact that 2NF ≫ 3NF ≫ 4NF. I will present the recent advances in more detail and put them into historical context. In addition, I will also provide a critical evaluation of the progress made including a discussion of the limitations of the ChEFT approach.
AZIMUTHAL ASYMMETRY AND CORRELATIONS OF HARD PHOTONS IN INTERMEDIATE ENERGY HEAVY ION COLLISIONS
Authors: LIU GUI-HUA , MA YU-GANG , CAI X. Z. , FANG D. Q. , GUO W. , SHEN W. Q. , TIAN W. D. , WANG H. W.
Published: September 2010

Hard photon emitted from energetic heavy ion collisions is of very interesting since it does not experience the late-stage nuclear interaction, therefore it is useful to explore the early-stage information of matter phase. In this work, we investigated the directed flow and elliptic flow for proton-neutron bremsstrahlung hard photons in intermediate energy heavy-ion collisions. The positive directed flow and negative elliptic flow of directed photons are illustrated and they seem to be anti-correlated to the free proton's flow. Also we calculated the two-photon correlation functions from which the information of photon source was extracted, and while two-photon azimuthal correlations are presented as a good method to extract the elliptic flow parameter v2 of direct hard photons.
NUCLEON-NUCLEON CROSS SECTIONS IN ISOSPIN ASYMMETRIC NUCLEAR MATTER
Authors: ZHANG HONGFEI , DONG JIANMIN , ZUO WEI , LOMBARDO UMBERTO
Published: September 2010

The in medium nucleon-nucleon (NN) cross sections in isospin asymmetric nuclear matter at various densities are investigated in the framework of Brueckner-Hartree-Fock theory with the Bonn B two-body nucleon-nucleon interaction supplemented with a new version microscopic three-body force (TBF). The TBF depresses the amplitude of cross sections at high density region. At low densities, the proton-proton and neutron-neutron cross sections decrease while the proton-neutron one increases as the asymmetry increases. But the sensitivity of the NN cross sections to the isospin asymmetry are reduced with the increasing density.
STATUS AND PROSPECTS OF HIRFL EXPERIMENTS ON NUCLEAR PHYSICS
Authors: XU H. S. , ZHENG C. , XIAO G. Q. , ZHAN W. L. , ZHOU X. H. , ZHANG Y. H. , SUN Z. Y. , WANG J. S. , GAN Z. G. , HUANG W. X. , MA X. W.
Published: September 2010

HIRFL is an accelerator complex consisting of 3 accelerators, 2 radioactive beams lines, 1 storage rings and a number of experimental setups. The research activities at HIRFL cover the fields of radio-biology, material science, atomic physics, and nuclear physics. This report mainly concentrates on the experiments of nuclear physics with the existing and planned experimental setups such as SHANS, RIBLL1, ETF, CSRe, PISA and HPLUS at HIRFL.
QUARK CONFINEMENT AND THE PROPERTIES OF QUARK MATTER
Authors: PENG G. X. , CHEN S. W. , CHANG Q. , TANG H. H.
Published: September 2010

The properties of two-flavor quark matter are investigated with a model which incorporates the confinement by density-dependent quark masses (CDDM). The results are compared with those in the conventional MIT bag model. It is found that the density behavior of quark matter in the two models are significantly different. Specially, the second derivative of the energy density can be negative in the CDDM while that in the bag model is always positive. This makes the velocity of sound very different in both models.
EFFECTS OF BULK VISCOSITY ON THE EVOLUTION OF RELATIVISTIC CAUSAL VISCOUS HYDRODYNAMICS
Authors: LI JIAN-WEI , MA YU-GANG , MA GUO-LIANG
Published: September 2010

The Hanbury-Brown Twiss (HBT) radii of Au + Au collisions at RHIC energy are investigated by a hydrodynamical expanding source with both shear (η) and bulk viscosities (ζ). With different height of the ratio of ζ to entropy density s, the ratio Rout/Rside of HBT radii can not describe the experimental data. But with large enough peak of ζ/s, the instability suggests that the source may clusterize which gives a hint to resolve the HBT puzzle.
A HAMILTON SOLVER FOR FINDING MODAL EIGENVALUES
Authors: WANG NING , WANG HAO ZHONG
Published: September 2010

A method is proposed for finding the normal mode eigenvalues in shallow water waveguide. We transform the problem determining eigenvalues in complex wave number plane into solving a "true" one dimensional Hamilton system. Simulations are performed, the result agrees very well with that calculated by the normal mode program KrakanC.
EXPERIMENTAL EVIDENCE OF HORIZONTAL REFRACTION BY NONLINEAR INTERNAL WAVES OF ELEVATION IN SHALLOW WATER IN THE SOUTH CHINA SEA: 3D VERSUS Nx2D ACOUSTIC PROPAGATION MODELING
Authors: REEDER D. BENJAMIN , CHIU LINUS Y. S. , CHEN CHI-FANG
Published: September 2010

A joint Taiwanese-U.S. field experiment was conducted in the South China Sea (SCS), entitled the South China Sea Oceanic Processes Experiment (Taiwan)/Non-Linear Internal Waves Initiative (US) (SCOPE/NLIWI), the ocean acoustics portion of which occurred during April 12–22, 2007. The acoustics objective was to quantify the temporal and spatial variability in acoustic propagation characteristics on the continental shelf in the presence of locally-generated and trans-basin nonlinear internal waves (NLIW). Broadband (400 Hz center frequency) m-sequence signals transmitted nearly continuously by a source moored near the seabed were received by vertical line arrays at 3 and 6 km range. The acoustic transect was oriented approximately parallel to the wave fronts of the shoaling trans-basin NLIW's which had crossed the deep basin from their origin in the Luzon Strait. The acoustic propagation variability due to strong vertical and horizontal refraction induced by the very large NLIW's creates an extremely complex acoustic field as a function of time and space. Experimental data and numerical acoustic propagation modeling results are presented to (1) examine and estimate the contribution of internal wave induced horizontal refraction to the received acoustic field; and (2) to quantify the range of propagation angles relative to the internal wave fronts within which strong horizontal refraction occurs and 3D propagation models are required to accurately predict the range- and depth-dependent acoustic propagation.
A DEDISPERSION TRANSFORM FOR SOUND PROPAGATION IN SHALLOW WATER WAVEGUIDE
Authors: GAO DA ZHI , WANG NING , WANG HAO ZHONG
Published: September 2010

For sound propagation in a shallow water waveguide, a dedispersion transform which can remove the dispersive effect of signal is described in this paper. The transform is a modified Fourier transform with two variables: translation and dispersion. Dispersive effect of signal for normal modes can be removed when these two variables match to real parameters. The validity of the present approach is verified in simulation and real data processing.
THREE-DIMENSIONAL ACOUSTIC SIMULATION OF AN ACOUSTIC REFRACTION BY A NONLINEAR INTERNAL WAVE IN A WEDGE BATHYMETRY
Authors: CHIU LINUS Y. S. , CHANG ANDREA Y. Y. , CHEN CHI-FANG , WEI RUEY-CHANG , YANG YING-JANG , REEDER D. BENJAMIN
Published: September 2010

Nonlinear internal wave (NIW) results in three dimensional acoustic effect such as ducting and whispering gallery effects in acoustic propagation. Acoustic energy restricted within internal wave crests (crest–crest) on the shelf constitutes the ducting effect, and energy confined along the crest when the source is located upslope from the NIW crest is known as the whispering gallery effect. Numerical experiments are presented in this paper for the study of 3D acoustic effects caused by both internal wave and wedge-bathymetry. 3D effects are predicted by Wide-Angle-FOR3D and the modal contents are calculated by MOS3DPEF. Following are the case studies detailing differences between 2D and 3D calculation, and the joint effect of propagating internal waves with upslope-bathymetry. Modeled time series of transmission Loss reveal that internal wave induces the oceanic waveguide and concentrate acoustic energy along the wave front. By modeling larger calculation ranges (20 km) and deeper deploying sources, the changing of the growth and decline of acoustic energy and lower acoustic mode amplitude by range, along the front of internal wave can be observed in this paper.
Accurate localization of a fall in pH within the ileocecal region: validation using a dual-scintigraphic technique
Authors: Zarate Natalia , Mohammed Sahar D. , O'Shaughnessy Emma , Newell Margaret , Yazaki Etsuro , Williams Norman S. , Lunniss Peter J. , Semler Jack R. , Scott S. Mark
Published: September 2010

Stereotypical changes in pH occur along the gastrointestinal (GI) tract. Classically, there is an abrupt increase in pH on exit from the stomach, followed later by a sharp fall in pH, attributed to passage through the ileocecal region. However, the precise location of this latter pH change has never been conclusively substantiated. We aimed to determine the site of fall in pH using a dual-scintigraphic technique. On day 1, 13 healthy subjects underwent nasal intubation with a 3-m-long catheter, which was allowed to progress to the distal ileum. On day 2, subjects ingested a pH-sensitive wireless motility capsule labeled with 4 MBq 51Chromium [EDTA]. The course of this, as it travelled through the GI tract, was assessed with a single-headed γ-camera using static and dynamic scans. Capsule progression was plotted relative to a background of 4 MBq 111Indium [diethylenetriamine penta-acetic acid] administered through the catheter. Intraluminal pH, as recorded by the capsule, was monitored continuously, and position of the capsule relative to pH was established. A sharp fall in pH was recorded in all subjects; position of the capsule relative to this was accurately determined anatomically in 9/13 subjects. In these nine subjects, a pH drop of 1.5 ± 0.2 U, from 7.6 ± 0.05 to 6.1 ± 0.1 occurred a median of 7.5 min (1–16) after passage through the ileocecal valve; location was either in the cecum ( n = 5), ascending colon ( n = 2), or coincident with a move from the cecum to ascending colon ( n = 2). This study provides conclusive evidence that the fall in pH seen within the ileocolonic region actually occurs in the proximal colon. This phenomenon can be used as a biomarker of transition between the small and large bowel and validates assessment of regional GI motility using capsule technology that incorporates pH measurement.
Activation of NFATc1 is directly mediated by IP3 in adult cardiac myocytes
Authors: Rinne Andreas , Blatter Lothar A.
Published: September 2010

The Ca2+-sensitive nuclear factor of activated T cell (NFAT) transcription factors are implicated in cardiac development and cellular remodeling associated with cardiac disease. In adult myocytes it is not resolved what specific Ca2+ signals control the activity of different NFAT isoforms in an environment that undergoes large changes of intracellular Ca2+ concentration with every heart beat. Cardiac myocytes possess the complete inositol 1,4,5-trisphosphate (IP3)/Ca2+-signaling cassette; however, its physiological and pathological significance has been a matter of ongoing debate. Therefore, we tested the hypothesis whether IP3 receptor activation regulates NFAT activity in cardiac myocytes. We used confocal microscopy to quantify the nuclear localization of NFATc1-green fluorescent protein (GFP) and NFATc3-GFP fusion proteins (quantified as the ratio of nuclear NFAT to cytoplasmic NFAT) in response to stimulation with neurohumoral agonists. In rabbit atrial myocytes, an overnight stimulation with endothelin-1, angiotensin II, and phenylephrine induced nuclear accumulation of NFATc1 that was sensitive to calcineurin inhibitors (cyclosporin A or inhibitor of NFAT-calcineurin association-6) and prevented by the IP3 receptor inhibitor 2-aminoethoxydiphenyl borate. Furthermore, a direct elevation of intracellular IP3 with a cell-permeable IP3 acetoxymethyl ester (10 μM) induced nuclear localization of NFATc1. With a fluorescence-based in vivo assay, we showed that endothelin-1 also enhanced the transcriptional activity of NFATc1 in atrial cells. The agonists failed to activate NFATc1 in rabbit ventricular cells, which express IP3 receptors at a lower density than atrial cells. They also did not activate NFATc3, an isoform that is highly influenced by nuclear export processes, in both cell types. Our data show that the second messenger IP3 is directly involved in the activation of NFATc1 in adult atrial cardiomyocytes.
Effect of initial gas bubble composition on detection of inducible intrapulmonary arteriovenous shunt during exercise in normoxia, hypoxia, or hyperoxia
Authors: Elliott Jonathan E. , Choi Yujung , Laurie Steven S. , Yang Ximeng , Gladstone Igor M. , Lovering Andrew T.
Published: September 2010

Concern has been raised that altering the fraction of inspired O2 (FiO2) could accelerate or decelerate microbubble dissolution time within the pulmonary vasculature and thereby invalidate the ability of saline contrast echocardiography to detect intrapulmonary arteriovenous shunt in subjects breathing either a low or a high FiO2. The present study determined whether the gaseous component used for saline contrast echocardiography affects the detection of exercise-induced intrapulmonary arteriovenous shunt under varying FiO2. Twelve healthy human subjects (6 men, 6 women) performed three 11-min bouts of cycle ergometer exercise at 60% peak O2 consumption (V̇o2peak) in normoxia, hypoxia (FiO2 = 0.14), and hyperoxia (FiO2 = 1.0). Five different gases were used to create saline contrast microbubbles by two separate methods and were injected intravenously in the following order at 2-min intervals: room air, 100% N2, 100% O2, 100% CO2, and 100% He. Breathing hyperoxia prevented exercise-induced intrapulmonary arteriovenous shunt, whereas breathing hypoxia and normoxia resulted in a significant level of exercise-induced intrapulmonary arteriovenous shunt. During exercise, for any FiO2 there was no significant difference in bubble score when the different microbubble gas compositions made with either method were used. The present results support our previous work using saline contrast echocardiography and validate the use of room air as an acceptable gaseous component for use with saline contrast echocardiography to detect intrapulmonary arteriovenous shunt during exercise or at rest with subjects breathing any FiO2. These results suggest that in vivo gas bubbles are less susceptible to changes in the ambient external environment than previously suspected.
Muscle energetics changes throughout maturation: a quantitative31P-MRS analysis
Authors: Tonson Anne , Ratel Sébastien , Le Fur Yann , Vilmen Christophe , Cozzone Patrick J. , Bendahan David
Published: September 2010

We quantified energy production in 7 prepubescent boys (11.7 ± 0.6 yr) and 10 men (35.6 ± 7.8 yr) using31P-magnetic resonance spectroscopy to investigate whether development affects muscle energetics, given that resistance to fatigue has been reported to be larger before puberty. Each subject performed a finger flexions exercise at 0.7 Hz against a weight adjusted to 15% of their maximal voluntary strength for 3 min, followed by a 15-min recovery period. The total energy cost was similar in both groups throughout the exercise bout, whereas the interplay of the different metabolic pathways was different. At the onset of exercise, children exhibited a higher oxidative contribution (50 ± 15% in boys and 25 ± 8% in men, P < 0.05) to ATP production, whereas the phosphocreatine breakdown contribution was reduced (40 ± 10% in boys and 53 ± 12% in men, P < 0.05), likely as a compensatory mechanism. The anaerobic glycolysis activity was unaffected by maturation. The recovery phase also disclosed differences regarding the rates of proton efflux (6.2 ± 2.5 vs. 3.8 ± 1.9 mM·pH unit−1·min−1, in boys and men, respectively, P < 0.05), and phosphocreatine recovery, which was significantly faster in boys than in men (rate constant of phosphocreatine recovery: 1.3 ± 0.5 vs. 0.7 ± 0.4 min−1; Vmax: 37.5 ± 14.5 vs. 21.1 ± 12.2 mM/min, in boys and men, respectively, P < 0.05). Our results obtained in vivo clearly showed that maturation affects muscle energetics. Children relied more on oxidative metabolism and less on creatine kinase reaction to meet energy demand during exercise. This phenomenon can be explained by a greater oxidative capacity, probably linked to a higher relative content in slow-twitch fibers before puberty.
Exercise training improves muscle vasodilatation in individuals with T786C polymorphism of endothelial nitric oxide synthase gene
Authors: Negrao Marcelo V. , Alves Cleber R. , Alves Guilherme B. , Pereira Alexandre C. , Dias Rodrigo G. , Laterza Mateus C. , Mota Gloria F. , Oliveira Edilamar M. , Bassaneze Vinícius , Krieger Jose E. , Negrao Carlos E. , Rondon Maria Urbana P. B.
Published: September 2010

Allele T at promoter region of the eNOS gene has been associated with an increase in coronary disease mortality, suggesting that this allele increases susceptibility for endothelial dysfunction. In contrast, exercise training improves endothelial function. Thus, we hypothesized that: 1) Muscle vasodilatation during exercise is attenuated in individuals homozygous for allele T, and 2) Exercise training improves muscle vasodilatation in response to exercise for TT genotype individuals. From 133 preselected healthy individuals genotyped for the T786C polymorphism, 72 participated in the study: TT ( n = 37; age 27 ± 1 yr) and CT+CC ( n = 35; age 26 ± 1 yr). Forearm blood flow (venous occlusion plethysmography) and blood pressure (oscillometric automatic cuff) were evaluated at rest and during 30% handgrip exercise. Exercise training consisted of three sessions per week for 18 wk, with intensity between anaerobic threshold and respiratory compensation point. Resting forearm vascular conductance (FVC, P = 0.17) and mean blood pressure ( P = 0.70) were similar between groups. However, FVC responses during handgrip exercise were significantly lower in TT individuals compared with CT+CC individuals (0.39 ± 0.12 vs. 1.08 ± 0.27 units, P = 0.01). Exercise training significantly increased peak VO2in both groups, but resting FVC remained unchanged. This intervention significantly increased FVC response to handgrip exercise in TT individuals ( P = 0.03), but not in CT+CC individuals ( P = 0.49), leading to an equivalent FVC response between TT and CT+CC individuals (1.05 ± 0.18 vs. 1.59 ± 0.27 units, P = 0.27). In conclusion, exercise training improves muscle vasodilatation in response to exercise in TT genotype individuals, demonstrating that genetic variants influence the effects of interventions such as exercise training.
Phase II Study of Daily Sunitinib in FDG-PET–Positive, Iodine-Refractory Differentiated Thyroid Cancer and Metastatic Medullary Carcinoma of the Thyroid with Functional Imaging Correlation
Authors: Carr Laurie L. , Mankoff David A. , Goulart Bernardo H. , Eaton Keith D. , Capell Peter T. , Kell Elizabeth M. , Bauman Julie E. , Martins Renato G.
Published: September 2010

Purpose: We conducted a phase II study to assess the efficacy of continuous dosing of sunitinib in patients with flurodeoxyglucose positron emission tomography (FDG-PET)–avid, iodine-refractory well-differentiated thyroid carcinoma (WDTC) and medullary thyroid cancer (MTC) and to assess for early response per FDG-PET.

Experimental Design: Patients had metastatic, iodine-refractory WDTC or MTC with FDG-PET–avid disease. Sunitinib was administered at 37.5 mg daily on a continuous basis. The primary end point was response rate per Response Evaluation Criteria in Solid Tumors (RECIST). Secondary end points included toxicity, overall survival, and time to progression. We conducted an exploratory analysis of FDG-PET response after 7 days of treatment.

Results: Thirty-five patients were enrolled (7 MTC, 28 WDTC), and 33 patients were evaluable for disease response. The primary end point, objective response rate per RECIST, was 11 patients (31%; 95% confidence interval, 16-47%). There were 1 complete response (3%), 10 partial responses (28%), and 16 patients (46%) with stable disease. Progressive disease was seen in 6 patients (17%). The median time to progression was 12.8 months (95% confidence interval, 8.9 months-not reached). Repeat FDG-PET was done on 22 patients. The median percent change in average standardized uptake values was −11.7%, −13.9%, and 8.6% for patients with RECIST response, stable disease, and progressive disease, respectively. Differences between response categories were statistically significant (P = 0.03). The most common toxicities seen included fatigue (11%), neutropenia (34%), hand/foot syndrome (17%), diarrhea (17%), and leukopenia (31%). One patient on anticoagulation died of gastrointestinal bleeding.

Conclusion: Continuous administration of sunitinib was effective in patients with iodine-refractory WDTC and MTC. Further study is warranted. Clin Cancer Res; 16(21); 5260–8. ©2010 AACR.
Threshold Suprachoroidal-Transretinal Stimulation Current Required by Different-Size Electrodes in Rabbit Eyes
Authors: Liang Ting , Zhao Liming , Sui Xiaohong , Zhou Chuanqing , Ren Qiushi , Qi Yanhua
Published: September 2010

Aims: To evaluate the threshold currents required by different-size electrodes under various stimulus parameters by suprachoroidal-transretinal stimulation (STS) in rabbit eyes. Methods: An electrode array with 4 differently sized electrode contacts (50, 150, 350 and 500 µm in diameter) was implanted into the suprachoroidal space of the rabbit eyes. The electrically evoked potential was recorded extradurally on the visual cortex, and the threshold was measured for each size electrode by a biphasic current pulse at the pulse durations of 0.25, 0.5, 0.75 and 1.0 ms. Stimuli were applied at 1, 2 and 4 Hz. Results: The current thresholds with the 50-µm electrode were 80 ± 21.2 and 41.4 ± 6.5 µA for 0.25- and 1.0-ms pulses, respectively. That obviously exceeded the limits for safe stimulation with platinum. Compared to 350- and 500-µm electrodes, a lower threshold can be obtained by the 150-µm electrode just at 1 Hz. And the most significant change in the threshold as the stimulus frequency increased to 4 Hz was obtained by the 150-µm electrode with short-duration pulse (0.25 ms). Conclusion: The large surface electrode with long-duration pulses may be preferable for the STS prosthesis. And stimuli with low frequency are suggested to be the safer choice.
Closure of Sclerotomies after 25- and 23-Gauge Transconjunctival Sutureless Pars Plana Vitrectomy Evaluated by Optical Coherence Tomography
Authors: Sawada Tomoko , Kakinoki Masashi , Sawada Osamu , Kawamura Hajime , Ohji Masahito
Published: September 2010

Aims: To evaluate sclerotomy closure after 25- and 23-gauge transconjunctival sutureless pars plana vitrectomy using optical coherence tomography (OCT). Methods: Forty-eight eyes (20 with a macular hole and 28 with an epiretinal membrane) of 47 patients (mean age, 66.5 years) who underwent one of the two procedures were included. Three sclerotomy sites in each eye were measured by cross-sectional OCT images vertical and parallel to the limbus on weeks 1 and 2 and months 1, 2 and 3 postoperatively. Results: After 25-gauge vitrectomy, the scleral wounds evaluated by OCT closed in 40.6% of the eyes at 1 week, 53.3% at 2 weeks, 60.5% at 1 month, 63.6% at 2 months and 63.9% at 3 months. There were significant differences in the closure rates between 1 week and 1 month (p = 0.015), 2 months (p = 0.007) and 3 months (p = 0.006) postoperatively. After 23-gauge vitrectomy, the scleral wounds closed in 31.6% of the eyes at 1 week, 50.0% at 2 weeks, 57.4% at 1 month, 63.0% at 2 months, and 61.1% at 3 months postoperatively. There were significant differences in the closure rates between 1 week and 1 month (p = 0.011), 2 months (p = 0.001) and 3 months (p = 0.002) postoperatively. The wound closure rates did not differ significantly between the two procedures. Conclusions: Scleral wounds after 25- and 23-gauge transconjunctival sutureless pars plana vitrectomy can be evaluated with OCT. Wound healing seems to be complete 2 weeks postoperatively.
Sharp-Object-Induced Open-Globe Injuries in Iranian Children Admitted to a Major Tertiary Center: A Prospective Review of 125 Cases
Authors: Ahmadabadi Mehdi Nili , Alipour Fateme , Tabataei Seyed Ali , Karkhane Reza , Rezaei Hoda , Ahmadabadi Elham Nili
Published: September 2010

Ocular trauma in children can result in catastrophic visual and psychological outcomes both for the child and his/her family. According to the WHO, childhood blindness is one of the major causes of avoidable blindness and so target of the Vision 2020 program. To achieve this program’s goals, it is necessary to explore the epidemiological patterns of ocular trauma in different countries which in its turn could be a valuable means to guide us in developing preventive measures. Our study is a hospital-based prospective study which was conducted to reveal detailed information about children who were admitted to a large tertiary care hospital with the diagnosis of lacerating globe injury due to a sharp object. Patients and Methods: During a 6-month period (December 2006 to June 2007), 125 eyes of 125 children (age ≤16 years) with the diagnosis of open-globe injury were enrolled. Clinical data were documented. Demographic data and details of the event were explored and documented based on the study questionnaire (adopting the Birmingham Eye Trauma Terminology and the United States Eye Injury Registry model as basis) by interviewing the parents and the child. Results: The mean age was 8.5 years (SD = 4.36 years, range: 1–16). The boys:girls ratio was 2.5:1; this ratio was age dependent, showing a significant increase with age. The home was the most frequent place (61.7%) for the trauma to occur in. Most traumas (50%) occurred in the afternoon (12 midday to 6 p.m.). Almost half of the traumas were unintentional self-injuries and occurred when the child was alone. A knife and fireworks were the two most frequent causes of injury. Conclusion: As the home is the most common place of ocular trauma in this age group and as lack of proper supervision and accessibility of sharp objects such as knives are the background of the event in most cases, it is strongly recommended to educate parents about providing a safe environment at home for their children. Work-related eye injuries in this age group should also be reduced by regulations for prohibiting children’s work or at least providing the necessary education and safety goggles.