bluuebunny/crossref_metadata_2025 huggingface dataset:
Schlieren formation in diatexite migmatite: examples from the St Malo migmatite terrane, France
Authors: Milord I. , Sawyer E. W.
Published: October 2010

Schlieren are trains of platy or blocky minerals, typically the ferromagnesian minerals and accessory phases, that occur in granites and melt‐rich migmatites, such as diatexites. They have been considered as: (1) unmelted residue from xenoliths or the source region; (2) mineral accumulations formed during magma flow; (3) compositional layering; and (4) sites of melt loss. In order to help identify schlieren‐forming processes in the diatexites at St Malo, differences in the size, shape, orientation, distribution and composition of the biotite from schlieren and from their hosts have been investigated.

Small biotite grains are much less abundant in the schlieren than in their hosts. Schlieren biotite grains are generally larger, have greater aspect ratios and have, except in hosts with low (< 10%) biotite contents, a much stronger shape preferred orientation than host biotite. The compositional ranges of host and schlieren biotite are similar, but schlieren biotite defines tighter, sharper peaks on composition‐frequency plots. Hosts show magmatic textures such as imbricated (tiled), unstrained plagioclase. Some schlieren show only magmatic textures (tiled biotite, no crystal‐plastic strain features), but many have textures indicating submagmatic and subsolidus deformation (e.g. kinked grains) and these schlieren show the most extensive evidence for recrystallization.

Magmas at St Malo initially contained a significant fraction of residual biotite and plagioclase crystals; smaller biotite grains were separated from the larger plagioclase crystals during magma flow. Since plagioclase was also the major, early crystallizing phase, the plagioclase‐rich domains developed rapidly and reached the rigid percolation threshold first, forcing further magma flow to be concentrated into narrowing melt‐rich zones where the biotite had accumulated, hence increasing shear strain and the degree of shape preferred orientation in these domains. Schlieren formed in these domains as a result of grain contacts and tiling in the grain inertia‐regime. Final amalgamation of the biotite aggregates into schlieren involved volume loss as melt trapped between grains was expelled after the rigid percolation threshold was reached in the biotite‐rich layers.
Petrological evolution of a suite of spinel granulites from Vizianagram, Eastern Ghats Belt, India, and genesis of sapphirine‐bearing assemblages
Authors: Sarkar S. , Dasgupta S. , Fukuoka M.
Published: October 2010

A suite of spinel–cordierite granulites from Viziangram, Eastern Ghats Belt, India preserve mineral assemblages and reaction textures indicative of peak metamorphic conditions of >1000 °C, >8<10 kbar, followed successively by near isobaric cooling (down to 750–800 °C), near isothermal decompression (to 4–5 kbar), and late hydration.P–Tconditions of each stage are evaluated through a combination of petrogenetic grid approach and thermobarometry. Sapphirine is developed in sillimanite‐bearing acid pegmatite veins that intruded the spinel–cordierite granulite close to peak metamorphic conditions, and also in the host rock in immediate contact with the pegmatite. Both sillimanite and sapphirine in the pegmatite are considered to be magmatic phases. Field observations and textural characteristics suggest that Al‐metasomatism of the spinel–cordierite granulite due to the intrusion of pegmatite was responsible for sapphirine formation in the spinel granulite.
Effect of three endodontic materials on the bond strength of two composite core materials to dentin
Authors: Al Wazzan Khalid A.
Published: October 2010

Purpose This study investigated the effect of dentin treatment with iodine potassium iodide, calcium hydroxide or a biphenol‐A‐ diglycidylether epoxy resin sealer on the dentin bond strength of titanium‐reinforced Bis‐GMA and urethane dimethacrylate composite materials.

Materials and Methods Dentin was exposed in four groups of extracted teeth (20 specimens each). Three groups were treated with one of the contaminants and the fourth group was left uncovered and served as the control group. All specimens were stored for 1 week at 37°C and 100% humidity. The dentin surfaces were cleaned with pumice slurry using a prophylaxis rubber cup, rinsed and dried. Then the dentin surfaces were treated using the conditioner and the primer of the GLUMA adhesive system followed by placement of composite core materials. After 20 minutes, debonding of the core materials was accomplished using a shear‐peel test. A two‐way analysis of variance and Tukey's multiple range test was performed based upon core type and contaminant type (α= 0.05).

Results Titanium‐reinforced Bis‐GMA composite showed significantly greater bond strength values than the urethane dimethacrylate composite material (p < 0.0001). The mean bond strength values in megapascals for the Bis‐GMA resin ranged from 8.47 ±1.52 for the calcium hydroxide group to 9.81 ±0.94 for the control group. Mean bond strengths for the urethane dimethacrylate resin ranged from 3.35 ±0.90 for calcium hydroxide to 3.99 ±0.88 for iodine potassium iodide groups. Within each core group, no difference in bond strengths were noted compared to the uncontaminated control.

Conclusion Pretreatment of the dentin with iodine potassium iodide, calcium hydroxide, or epoxy resin followed by pumicing and using the GLUMA system conditioner and primer had no effect on the bond strength of the two resin composite core materials. However, the titanium reinforced Bis‐GMA composite exhibited significantly greater bond strength to dentin than the urethane dimethacrylate based composite.
Cast articulation accuracy using rigid cast stabilization
Authors: Gunderson Ronald Bruce , Siegel Sharon Crane
Published: October 2010

Purpose This study evaluated the positional accuracy of casts articulated on a semi‐adjustable articulator, with and without rigid cast stabilization using either laboratory plaster or mounting plaster.

Materials and Methods A reference articulation of melamine casts in maximum articulation was established and recorded in the horizontal and vertical dimensions using a verification device. The same casts were subsequently remounted 24 times using either laboratory plaster or mounting plaster. Half of the articulations from each group were stabilized using detachable mounting rods and sticky wax, and half were hand‐articulated without stabilization, for a total of 6 articulations in each of 4 test groups. The resulting spatial positions established on the articulator were compared to the initial reference position on the verification device grid. Means and standard deviations of the absolute values of the horizontal and vertical displacement for each group were determined separately and compared using a one‐way anaylsis of variance. Significant differences (p < 0.05) were identified using Tukey's honestly significant difference multiple comparison test.

Results Mean vertical mandibular cast displacement ranged from 0.26 ±0.21mm for stabilized casts mounted with laboratory plaster to 1.58 ±0.32 mm for unstabilized casts mounted with mounting plaster. For each mounting material, significantly less vertical displacement (p < 0.001) was observed with the mandibular cast stabilized before mounting. The cast mounted with laboratory plaster exhibited horizontal displacement (0.87 ±0.29 mm) that was significantly greater than the remaining groups (p < 0.001), which did not differ from each other.

Conclusions Rigid stabilization of the mandibular to maxillary cast during mounting with laboratory and mounting plaster improved articulation accuracy.
Implant dentistry in predoctoral education: The elective approach
Authors: Maalhagh‐Fard Ahmad , Nimmo Arthur , Lepczyk James W. , Pink Frank E.
Published: October 2010

In response to interest by dental students and patient needs, an elective program in implant dentistry was started at the University of Detroit Mercy School of Dentistry (UDM) in the summer of 1994. The 1‐year program is offered to a group of 10 senior students out of a class of 72. Implant treatment is provided to selected edentulous and partially edentulous patients. Predoctoral students participate in diagnosis and treatment planning, assist in surgical placement, and perform the prosthodontic procedures. A survey was sent to 160 UDM graduates, and 90 responded. Out of the 90 respondents, 35% had participated in the elective implant program and 65% had not. A Pearson correlation matrix was used to analyze their responses. A stronger positive correlation with offering and restoring implants was seen in graduates who had completed the elective program in implant dentistry.
Retention strengths of five luting cements on prefabricated dowels after root canal obturation with a zinc oxide/eugenol sealer: 1. Dowel space preparation/cementation at one week after obturation
Authors: Hagge Mark S. , Wong Ralan D.M. , Lindemuth James S.
Published: October 2010

Purpose This investigation examined the effect of 5 different cements on the retention strength of prefabricated endodontic dowels placed into root canals previously obturated with gutta percha and a zinc oxide/eugenol (ZOE) sealer.

Materials and Methods Ninety‐six single‐rooted teeth were decoronated, filed, cleaned, sequentially shaped, and divided into 6 groups of 16 specimens each. Five of the groups were then obturated with gutta percha and a ZOE sealer. One group was not obturated and served as the control group. Dowel space preparation and dowel cementation for all groups were completed 1 week later. Ten‐mm deep dowel spaces were prepared using size 6 Gates Glidden drills. Size 5 Paraposts were then cemented with 5 different cements: Panavia 21 for group 1 (unobturated controls) and group 2; Ketac‐Cem glass ionomer for group 3; Fleck's zinc phosphate for group 4; Parapost (composite) Cement for group 5; and C&B Metabond 4‐META for group 6. After 48 hours, the dowels were removed using a universal testing machine in tensile mode at 1 mm min−1.

Results The following results were found (all values in kg): group 1 (controls; Panavia 21) mean = 61.81, 95% CI =±8.65; group 2 (Panavia 21), mean=43.15, 95% CI =±7.81; group 3 (Ketac‐Cem), mean =34.45, 95% CI =±4.93; group 4 (zinc phosphate), mean = 25.07, 95% CI =±5.03; group 5 (Parapost Cement), mean = 24.99, 95% CI =±5.35. None of the group 6 (C&B Metabond) specimens developed measurable bond strengths, so this group was excluded from parametric statistical analyses. An analysis of variance (ANOVA) showed a significant effect of group; pairwise multiple comparison procedures (Tukey test) showed that group 1 (controls) had significantly greater retention than all other groups (p <0.001); group 2 (Panavia 21) had significantly greater retention than groups 4 (zinc phosphate) and 5 (Parapost cement) (p <0.001). None of the other pairwise comparisons were statistically different.

Conclusions Paraposts cemented with Panavia 21 in unobturated root canals exhibited significantly higher retention than Paraposts luted with Panavia 21 and 4 different cements into dowel spaces prepared 1 week after obturation with gutta percha/ZOE sealer (p <0.001). Among the obturated groups, Panavia 21 cement (group 2) demonstrated significantly greater retention of Paraposts than zinc phosphate (group 4) and Parapost composite (group 5) cements (p <0.001). Ketac‐Cem glass ionomer cement (group 3) had intermediate retention values that were not statistically different than those of groups 2, 4, and 5 (p >0.05). The 4‐META cement, C&B Metabond, failed to polymerize.
A system for the diagnosis, placement, and prosthetic restoration of root form implants (U.S. Patent #5,769,636)
Authors: Di Sario Francesco
Published: October 2010

It is difficult to achieve a high degree of reproducibility when using a diagnostic wax‐up as the template for fabrication of a definitive implant restoration. Here a method for implant prosthesis treatment planning is described that allows fabrication of the provisional restoration before surgical placement of the implant. The method involves 6 steps: (1) determining the mesiodistal inclination of the implant, (2) determining the buccolingual dimension of the alveolar ridge, (3) determining the proper position of the implant, (4) fabricating the surgical guide, (5) fabricating the provisional restoration, and (6) performing surgical placement of the implant followed by immediate placement of the provisional restoration.
Immediate loading of dental implants in partially edentulous patients: A clinical report
Authors: Chatzistavrou Maria , Felton David A. , Cooper Lyndon F.
Published: October 2010

Immediate loading of dental implants offers attractive advantages for patient and prosthodontist alike. Current data support immediate loading of splinted screw‐shaped implants in the parasymphysis region. This report presents a case of a partially edentulous patient successfully restored with a fixed implant prosthesis following an immediate loading protocol.
Spatially resolved high-resolution x-ray spectroscopy of high-current plasma-focus discharges
Authors: Zając S. , Rzadkiewicz J. , Rosmej O. , Scholz M. , Yongtao Zhao , Gójska A. , Paduch M. , Zielińska E.
Published: October 2010

Soft x-ray emission from a Mather-type plasma-focus device (PF-1000) operated at ∼400 kJ was measured. The high density and temperature plasma were generated by the discharge in the deuterium-argon gas mixture in the modified (high-current) plasma-focus configuration. A spherically bent mica crystal spectrograph viewing the axial output of the pinch region was used to measure the x-ray spectra. Spatially resolved spectra including the characteristic x-ray lines of highly ionized Ar and continua were recorded by means of an x-ray film. The x-ray emission of PF-1000 device was studied at different areas of the pinch.
Measurement of poloidal velocity on the National Spherical Torus Experiment (invited)
Authors: Bell Ronald E. , Feder Russell
Published: October 2010

A diagnostic suite has been developed to measure the impurity poloidal flow using charge exchange recombination spectroscopy on the National Spherical Torus Experiment. Toroidal and poloidal viewing systems measure all the quantities required to determine the radial electric field. Two sets of up/down symmetric poloidal views are used to measure both the active emission in the plane of the neutral heating beams and the background emission in a radial plane away from the neutral beams. Differential velocity measurements isolate the line-integrated poloidal velocity from apparent flows due to the energy-dependent charge exchange cross section. Six f/1.8 spectrometers measure 276 spectra to obtain 75 active and 63 background channels every 10 ms. The local measurements from a similar midplane toroidal viewing system are mapped into two dimensions to allow the inversion of poloidal line-integrated measurements to obtain local poloidal velocity profiles. The radial resolution after inversion is 0.6–1.8 cm from the plasma edge to the center.
Analytical solutions of the heat diffusion equation for 3ω method geometry
Authors: Duquesne J.-Y. , Fournier D. , Frétigny C.
Published: October 2010

“3ω” experiments aim at measuring thermal conductivities and diffusivities. Data analysis relies on integral expressions of the temperature. In this paper, we derive new explicit analytical formulations of the solution of the heat diffusion equation, using Bessel, Struve, and Meijer-G functions, in the 3ω geometry for bulk solids. These functions are available in major computational tools. Therefore numerical integrations can be avoided in data analysis. Moreover, these expressions enable rigorous derivations of the asymptotic behaviors. We also underline that the diffusivity can be extracted from the phase data without any calibration while the conductivity measurement requires a careful one.
Surface pump-probe femtosecond-laser mass spectrometry: Time-, mass-, and velocity-resolved detection of surface reaction dynamics
Authors: Vaida Mihai E. , Bernhardt Thorsten M.
Published: October 2010

A detailed account of the experimental methodology of surface pump-probe femtosecond-laser mass spectrometry is presented. This recently introduced technique enables the direct time-resolved investigation of surface reaction dynamics by monitoring the mass and the relative velocity of intermediates and products of a photoinduced surface reaction via multiphoton ionization. As a model system, the photodissociation dynamics of methyl iodide adsorbed at submonolayer coverage on magnesia ultrathin films is investigated. The magnesia surface preparation and characterization as well as the pulsed deposition of methyl iodide are described. The femtosecond-laser excitation (pump) and, in particular, the resonant multiphoton ionization surface detection (probe) schemas are discussed in detail. Results of pump-probe time-resolved methyl and iodine atom detection experiments are presented and the potential of this method for velocity-resolved photofragment analysis is evaluated.
Green and ultraviolet pulse generation with a compact, fiber laser, chirped-pulse amplification system for aerosol fluorescence measurements
Authors: Lou Janet W. , Currie Marc , Sivaprakasam Vasanthi , Eversole Jay D.
Published: October 2010

We use a compact chirped-pulse amplified system to harmonically generate ultrashort pulses for aerosol fluorescence measurements. The seed laser is a compact, all-normal dispersion, mode-locked Yb-doped fiber laser with a 1050 nm center wavelength operating at 41 MHz. Average powers of more than 1.2 W at 525 nm and 350 mW at 262 nm are generated with <500 fs pulse durations. The pulses are time-stretched with high-dispersion fiber, amplified by a high-power, large-mode-area fiber amplifier, and recompressed using a chirped volume holographic Bragg grating. The resulting high-peak-power pulses allow for highly efficient harmonic generation. We also demonstrate for the first time to our knowledge, the use of a mode-locked ultraviolet source to excite individual biological particles and other calibration particles in an inlet air flow as they pass through an optical chamber. The repetition rate is ideal for biofluorescence measurements as it allows faster sampling rates as well as the higher peak powers as compared to previously demonstrated Q-switched systems while maintaining a pulse period that is longer than the typical fluorescence lifetimes. Thus, the fluorescence excitation can be considered to be quasicontinuous and requires no external synchronization and triggering.
Avalanche photodiode based detector for beam emission spectroscopy
Authors: Dunai D. , Zoletnik S. , Sárközi J. , Field A. R.
Published: October 2010

An avalanche photodiode based (APD) detector for the visible wavelength range was developed for low light level, high frequency beam emission spectroscopy (BES) experiments in fusion plasmas. This solid state detector has higher quantum efficiency than photomultiplier tubes, and unlike normal photodiodes, it has internal gain. This paper describes the developed detector as well as the noise model of the electronic circuit. By understanding the noise sources and the amplification process, the optimal amplifier and APD reverse voltage setting can be determined, where the signal-to-noise ratio is the highest for a given photon flux. The calculations are compared to the absolute calibration results of the implemented circuit. It was found that for a certain photon flux range, relevant for BES measurements (≈108–1010 photons/s), the new detector is superior to both photomultipliers and photodiodes, although it does not require cryogenic cooling of any component. The position of this photon flux window sensitively depends on the parameters of the actual experimental implementation (desired bandwidth, detector size, etc.) Several detector units based on these developments have been built and installed in various tokamaks. Some illustrative results are presented from the 8-channel trial BES system installed at Mega-Ampere Spherical Tokamak (MAST) and the 16-channel BES system installed at the Torus Experiment for Technology Oriented Research (TEXTOR).
Interpretation of high-resolution images of the best-bound wetting layers on Pt(111)
Authors: Feibelman Peter J. , Bartelt N. C. , Nie S. , Thürmer K.
Published: October 2010

Two interpretations have been proposed of dark triangles observed in scanning tunneling microscopy (STM) images of the best bound, √37×√37−R25.3°, and √39×√39−R16.1° periodic water monolayers on Pt(111). In one, a “Y”-shaped tetramer of water molecules is removed, leaving a vacancy island behind; the other assumes the Y is replaced by a hexagon of H2O molecules, amounting to a di-interstitial. Consistent only with the di-interstitial model are thermal desorption and CO coadsorption data, STM line scans, and total energies obtained from density functional theory calculations.
Nondestructive measurement of refractive index profile of gradient refractive index rod lens
Authors: Lv Hao , Liu Aimei , Tong Jufang , Yi Xunong , Li Qianguang , Wang Xinmin , Ding Yaoming
Published: October 2010

In this paper, a simple nondestructive method is described to obtain the refractive index profile of a gradient refractive index rod lens by means of optical coherence tomography. The approach exploits the fact that optical coherence tomography provides a direct measurement of the optical path of the light traveled through a gradient refractive index rod lens. The refractive index profile for a gradient refractive index rod lens is retrieved by iterative fitting of the optical path calculated by the ray tracing method with that experimentally measured using optical coherence tomography. The measured refractive index profile is in good agreement with theory.
Long term plumb-line alignment of precise measuring instruments: An adaptive digital controller designed for an autoleveling platform
Authors: D’Agostino Giancarlo , Germak Alessandro , Berrino Giovanna
Published: October 2010

Plumb-line alignment can affect the sensors of precise scientific instruments. When its effect is one of the main contributors to the measurement uncertainty, the deviation from the true vertical must be continuously monitored or compensated. This paper describes a digital control system designed and tested for an autoleveling platform. Best performances are obtained with an adaptive digital compensator based on a convolution of the error signal. Although accuracy and resolution of the leveling transducer limit the ultimate sensitivity, laboratory tests showed that the controller kept for several hours the base-plate top within ±1 μrad. These performances are suitable for maintaining the alignment of relative spring gravimeters used by volcanologists in long-term gravity measurements.
H
2
-decoupling-accelerated H1 spin diffusion in dynamic nuclear polarization with photoexcited triplet electrons
Authors: Negoro M. , Nakayama K. , Tateishi K. , Kagawa A. , Takeda K. , Kitagawa M.
Published: October 2010

In dynamic nuclear polarization (DNP) experiments applied to organic solids for creating nonequilibrium, high H1 spin polarization, an efficient buildup of H1 polarization is attained by partially deuterating the material of interest with an appropriate H1 concentration. In such a dilute H1 spin system, it is shown that the H1 spin diffusion rate and thereby the buildup efficiency of H1 polarization can further be enhanced by continually applying radiofrequency irradiation for deuterium decoupling during the DNP process. As experimentally confirmed in this work, the electron spin polarization of the photoexcited triplet state is mainly transferred only to those H1 spins, which are in the vicinity of the electron spins, and H1 spin diffusion transports the localized H1 polarization over the whole sample volume. The H1 spin diffusion coefficients are estimated from DNP repetition interval dependence of the initial buildup rate of H1 polarization, and the result indicates that the spin diffusion coefficient is enhanced by a factor of 2 compared to that without H2 decoupling.
Modified, semiconducting graphene in contact with a metal: Characterization of the Schottky diode
Authors: Nourbakhsh Amirhasan , Cantoro Mirco , Hadipour Afshin , Vosch Tom , van der Veen Marleen H. , Heyns Marc M. , Sels Bert F. , De Gendt Stefan
Published: October 2010

In this paper, we report the fabrication and characterization of Schottky rectifying junctions between semiconducting, modified single-layer graphene and a metal. The pristine, semimetallic behavior of graphene is altered by controlled exposure to an oxygen plasma, resulting in the opening of an optical band gap as shown by photoluminescence spectroscopy. The occurrence of a Schottky barrier between semiconducting graphene and metals with different work functions (Al, Cr, Pd, and Yb) is investigated by electrically characterizing the as-fabricated junctions. The rectifying properties of our Schottky diodes show the potential of semiconducting, modified graphene as building block of elementary logic circuits.
High temperature annealing induced superparamagnetism in CoFeB/MgO/CoFeB tunneling junctions
Authors: Kou Xiaoming , Wang Weigang , Fan Xin , Shah Lubna R. , Tao Rae , Xiao John Q.
Published: October 2010

We have investigated the evolution of the magnetic transport properties as a function of short annealing time in CoFeB/MgO/CoFeB based magnetic tunnel junctions (MTJs) with a free layer of 2 nm. It is found that the hysteresis behaviors in magnetoresistance (MR) loops disappear in samples annealed for 17 min. The linear region between MR and the applied field gradually increases. The MR loops without hysteresis can be well fitted by using the superparamagnetism theory, suggesting the formation of superparamagnetic particles in the free layer during the high temperature annealing. The control of MTJ properties with annealing time is desirable in magnetic field sensor productions.
Improved calibration technique of the infrared imaging bolometer using ultraviolet light-emitting diodes
Authors: Drapiko E. , Peterson B. , Alekseev A. , Seo D. C.
Published: October 2010

The technique used until recently utilizing the Ne–He laser for imaging bolometer foils calibration [B. J. Peterson et al., J. Plasma Fusion Res. 2, S1018 (2007)] has showed several issues. The method was based on irradiation of 1 cm spaced set of points on a foil by the laser beam moved by set of mirrors. Issues were the nonuniformity of laser power due to the vacuum window transmission nonuniformity and high reflection coefficient for the laser. Also, due to the limited infrared (IR) window size, it was very time consuming. The new methodology uses a compact ultraviolet (uv) light-emitting diodes installed inside the vacuum chamber in a fixed position and the foil itself will be moved in the XY directions by two vacuum feedthroughs. These will help to avoid the above mentioned issues due to lack of a vacuum window, fixed emitters, higher uv power absorption, and a fixed IR camera position.
Communication: Systematic shifts of the lowest unoccupied molecular orbital peak in x-ray absorption for a series of 3d metal porphyrins
Authors: García-Lastra J. M. , Cook P. L. , Himpsel F. J. , Rubio A.
Published: October 2010

Porphyrins are widely used as dye molecules in solar cells. Knowing the energies of their frontier orbitals is crucial for optimizing the energy level structure of solar cells. We use near edge x-ray absorption fine structure (NEXAFS) spectroscopy to obtain the energy of the lowest unoccupied molecular orbital (LUMO) with respect to the N1s core level of the molecule. A systematic energy shift of the N1s to LUMO transition is found along a series of 3d metal octaethylporphyrins and explained by density functional theory. It is mainly due to a shift of the N1s level rather than a shift of the LUMO or a change in the electron-hole interaction of the core exciton.
Thermoelectric properties and crystallographic shear structures in titanium oxides of the Magnèli phases
Authors: Harada Shunta , Tanaka Katsushi , Inui Haruyuki
Published: October 2010

The thermoelectric properties of Magnèli phase titanium oxides TinO2n−1 (n=2,3,…) have been investigated, paying special attention to how the thermoelectric performance can be altered by changing the microstructure. Dense polycrystalline specimens with nominal composition of TiO2−x (x=0.05, 0.10, 0.15, and 0.20) prepared by conventional hot-pressing are all identified to be one of the Magnèli phases, in which crystallographic shear planes are regularly introduced according to the oxygen deficiency. Electrical conduction is n-type for all specimens and the carrier concentration increases with the increase in the oxygen deficiency. The values of lattice thermal conductivity, on the other hand, decrease with the increase in the oxygen deficiency, which can be attributed to phonon scattering at the crystallographic shear plane. The largest value of thermoelectric figure of merit Z, 1.6×10−4 K−1 was obtained at 773 K for the hot-pressed specimen of TiO1.90.
Much simplified ion-beam assisted deposition-TiN template for high-performance coated conductors
Authors: Xiong J. , Matias V. , Wang H. , Zhai J. Y. , Maiorov B. , Trugman D. , Tao B. W. , Li Y. R. , Jia Q. X.
Published: October 2010

A much simplified template, i.e., two nonsuperconducting layers between the superconducting YBa2Cu3O7−δ (YBCO) and the polycrystalline metal substrate, has been developed for high-performance coated conductors by using biaxially aligned TiN as a seed layer. A combination of a thin TiN (∼10 nm by ion-beam assisted deposition) layer and an epitaxial buffer LaMnO3 layer (∼120 nm) allows us to grow epitaxial YBCO films with values of full width at half-maximum around 3.5° and 1.7° for the ϕ-scan of (103) and rocking curve of (005) YBCO, respectively. The YBCO films grown on electropolished polycrystalline Hastelloy using this two-layer template exhibited a superconducting transition temperature of 89.5 K, a critical current density of 1.2 MA/cm2 at 75.5 K, and an α value (proportional factor of critical current density Jc∼H−α) of around 0.33, indicating a high density of pinning centers and an absence of weak links.
Diffraction and fringing field effects in small pixel liquid crystal devices with homeotropic alignment
Authors: Vanbrabant Pieter J. M. , Beeckman Jeroen , Neyts Kristiaan , Willman Eero , Fernandez F. Anibal
Published: October 2010

Reducing the pixel dimensions of liquid crystal microdisplays in search of high resolution has a fundamental impact on their electro-optic behavior. The liquid crystal director orientation becomes distorted due to fringing fields and diffraction effects influence the optical characteristics of the device once the structure features approach the wavelength of the incident light. Three-dimensional finite element simulation of the liquid crystal dynamics with a variable order approach is combined with a full-vector beam propagation analysis to investigate how elasticity and diffraction limit the resolution as a function of the pixel size for transmissive and reflective architectures with vertical liquid crystal alignment. The key liquid crystal properties are considered and the importance of materials with high birefringence is confirmed for small pixel devices as these improve the contrast for a fixed pixel size.
Breakdown temperature of electrons in SF6 gas
Authors: Uhm Han S. , Choi Eun H. , Cho Guangsup , Ryu Han-Yong
Published: October 2010

The breakdown temperature Tb of electrons in SF6 gas is obtained by expressing the ionization and attachment coefficients of the gas in terms of the electron temperature Te assuming that the electron energy in the gas is in a Maxwellian distribution. The sparking criterion of the SF6 gas was obtained in terms of the gas pressure p and the anode-cathode distance d. It was found that the breakdown temperature Tb of electrons in SF6 in a high-pressure gas characterized by pd⪢0.001 is 4.9 eV, which is independent of the parameter pd. Here, pd is in units of atm cm.
The effect of excess atomic volume on He bubble formation at fcc–bcc interfaces
Authors: Demkowicz M. J. , Bhattacharyya D. , Usov I. , Wang Y. Q. , Nastasi M. , Misra A.
Published: October 2010

Atomistic modeling shows that Cu–Nb and Cu–V interfaces contain high excess atomic volume due to constitutional vacancy concentrations of ∼5 at. % and ∼0.8 at. %., respectively. This finding is supported by experiments demonstrating that an approximately fivefold higher He concentration is required to observe He bubbles via through-focus transmission electron microscopy at Cu–Nb interfaces than in Cu–V interfaces. Interfaces with structures tailored to minimize precipitation and growth of He bubbles may be used to design damage-resistant composites for fusion reactors.
Size-dependent electro-osmosis in a microchannel with low-permittivity, salt-free media
Authors: Chang Feng-Ming , Chang Yi-Wen , Sheng Yu-Jane , Tsao Heng-Kwong
Published: October 2010

Electro-osmosis is the preferred transport mechanism in microfluidic systems. The electro-osmotic mobility in an aqueous solution is essentially independent of the microchannel size. However, in low-permittivity solvents, the screening effect is absent and the mobility is found to grow with the capillary radius according to our analytical theory and electro-osmotic flow experiments. Our results show that regardless of low surface charge density, electro-osmosis always occurs for long enough microchannels. Therefore, electro-osmosis provides a method for determining extremely low surface charge density associated with low-permittivity media. The implication in the response time of electronic paper is given as well.
Narrow bandwidth and highly polarized ratio infrared thermal emitter
Authors: Chen Hung-Hsin , Jiang Yu-Wei , Wu Yi-Ting , Chang Pei-En , Chang Yi-Tsung , Huang Hao-Fu , Lee Si-Chen
Published: October 2010

Polarized infrared thermal emitters consisting of a waveguide thermal emitter combined with silver grating structure were studied. For a device containing a perforated silver film under the grating, polarized infrared light was emitted only when the wavelength satisfied the standing wave condition, therefore the broad bandwidth SiO2 phonon vibration modes were suppressed in the thermal radiation spectrum. The polarized ratio with different grating thickness was investigated and the highly polarized ratio up to 0.875 was achieved. This study demonstrated that the integrated structure can be used as a narrow bandwidth and highly polarized ratio infrared light source.
Structural and resistance switching properties of ZnO/SrTiO3/GaAs heterostructure grown by laser molecular beam epitaxy
Authors: Huang W. , Dai J. Y. , Hao J. H.
Published: October 2010

ZnO thin films were epitaxially grown on (001) GaAs substrate by laser molecular beam epitaxy with SrTiO3 (STO) as a buffer layer. The interface properties of ZnO/GaAs heterostructure are greatly improved by inserting STO buffer layer. The interfacial effects on the transport and dielectric characteristics of the heterostructure have been investigated. The current-voltage characteristic of the heterostructure reveals an asymmetric and resistance switching behavior, exhibiting a temperature-dependent resistance hysteresis in the temperature range of 50–300 K. These measured properties could be attributed to the charge effect at the interface of the heterostructure.
Ultrafast optical imaging by molecular wakes
Authors: Wu Jian , Lu Peifen , Liu Jia , Li Hao , Pan Haifeng , Zeng Heping
Published: October 2010

Ultrafast optical imaging is demonstrated by ultrashort laser pulse induced impulsive molecular alignment, involving optical image storage in the created molecular wakes followed by periodic readout and display. For diatomic molecules in air, both raised and intagliated monochromatic images are demonstrated, which is field-free, periodically achievable, and works as an ultrafast buffer memory for the imprinted optical images. Analogous to the holographic imaging, the phase information of a three-dimensional object can be revealed at various time delays.
Photoelectron spectroscopy and density functional theory study of TiAlOy− (y=1–3) and TiAl2Oy− (y=2–3) clusters
Authors: Zhang Zeng-Guang , Xu Hong-Guang , Zhao Yuchao , Zheng Weijun
Published: October 2010

Small titanium-aluminum oxide clusters, TiAlOy− (y=1–3) and TiAl2Oy− (y=2–3), were studied by using anion photoelectron spectroscopy. The adiabatic detachment energies of TiAlOy− (y=1–3) were estimated to be 1.11±0.05, 1.70±0.08, and 2.47±0.08 eV based on their photoelectron spectra; those of TiAl2O2− and TiAl2O3− were estimated to be 1.17±0.08 and 2.2±0.1 eV, respectively. The structures of these clusters were determined by comparison of density functional calculations with the experimental results. The structure of TiAlO− is nearly linear with the O atom in the middle. That of TiAlO2− is a kite-shaped structure. TiAlO3− has a kite-shaped TiAlO2 unit with the third O atom attaching to the Ti atom. TiAl2O2− has two nearly degenerate Al–O–Ti–O–Al chain structures that can be considered as cis and trans forms. TiAl2O3− has two low-lying isomers, kite structure and book structure. The structures of these clusters indicate that the Ti atom tends to bind to more O atoms.
Predicted responses in Merino sheep from selection combining visually assessed and measured traits
Authors: Mortimer S. I. , Atkins K. D. , Semple S. J. , Fogarty N. M.
Published: October 2010

Visually assessed traits for wool quality and ease of management are important to Merino sheep breeders and need to be considered in breeding programs. The present study reports on the predicted correlated responses in visual traits from selection using a range of standard MERINOSELECT™ indices available for use in Australian Merino breeding programs. The effect of including a visual trait in the index is also reported. The visual scored traits were classer grade, wool quality (handle, character and colour), conformation (neck and body wrinkle, front and back leg structure) and fleece rot. The indices covered a range of micron premiums of varying emphasis on increasing fleece weight and reducing fibre diameter. The indices were for Merino wool enterprises (Merino 14%, Merino 7% and Merino 3.5%) and Merino dual purpose wool and meat enterprises (Dual Purpose 7% and Dual Purpose 3.5%). The breeding objectives for the indices included fleece weight, fibre diameter, coefficient of variation of fibre diameter, staple strength, bodyweight and reproduction. Selection over 10 years using the standard MERINOSELECT™ indices is predicted to result in a small correlated improvement in the wool quality traits and classer grade, with a slight deterioration in fleece rot score. The improvement in wool handle, character and colour are greater with those indices that have a greater emphasis on reducing fibre diameter than with those increasing fleece weight. Indices with more emphasis on increased fleece weight than on reduced fibre diameter are predicted to result in small increases in neck and body wrinkle scores and a slight deterioration in wool colour. Inclusion of classer grade, handle, character or colour provided slight extra gains in fleece weight for indices that emphasised reduced fibre diameter through increased accuracy of selection.
Aerenchyma formation: programmed cell death in adventitious roots of winter wheat (Triticum aestivum) under waterlogging
Authors: Jiang Zhen , Song Xue-Fang , Zhou Zhu-Qing , Wang Li-Kai , Li Ji-Wei , Deng Xiang-Yi , Fan Hai-Yan
Published: October 2010

This study determined the characteristics of cortical cell death in wheat (Triticum aestivum L.) roots during programmed cell death (PCD) and the relationship between PCD and acid phosphatases. An examination of morphological development by light microscrope revealed that aerenchyma formed in roots waterlogged for 24 h and well developed aerenchyma formed in roots waterlogged for 120 h. The first detectable events were observed by electron microscopy and included plasma membrane invagination and the appearance of vesicles between the plasma membrane and the cell wall. Later, chromatin condensation and double-membrane-bound structures resembling autophagosomes were observed. The activity of acid phosphatases gradually increased during waterlogging and was present during the entire process of cell death. These observations suggest that cortical cell death during aerenchyma formation induced by waterlogging was a form of PCD. Acid phosphatases play an important role in PCD induced by waterlogging, being responsible for the hydrolysis of cell components at the later stages of PCD.
Identification of the lipoxygenase gene family from Vitis vinifera and biochemical characterisation of two 13-lipoxygenases expressed in grape berries of Sauvignon Blanc
Authors: Podolyan Andriy , White Jackie , Jordan Brian , Winefield Chris
Published: October 2010

Lipoxygenases (LOXs) are a group of non-haem iron-containing dioxygenases that catalyse oxygenation of polyunsaturated fatty acids (PUFAs) and lipids, and initiate the formation of biologically active compounds known as oxylipins. Several plant oxylipins comprise important flavours and aromas in food and beverages. Analysis of the grape (Vitis vinifera L.) genome revealed that the grape LOX family consists of 18 individual members. Phylogenetic analysis places all except one of the identified grape LOXs into either a type II 13-LOX cluster or the type I 9-LOX cluster. Four LOX genes (VvLOXA, VvLOXO, VvLOXC, VvLOXD), representative of the major LOX groupings observed in the phylogenetic analyses, were selected for analysis of patterns of transcript abundance in berry tissues. VvLOXA and VvLOXO represent putative 13-LOXs, while VvLOXC represents a putative 9-LOX. VvLOXD represents a unique LOX that differs significantly from other characterised plant LOXs. All four LOXs exhibited a complex pattern of gene expression. Across all developmental stages, VvLOXA was the most abundant LOX and was expressed predominantly in berry skins. The expression pattern of VvLOXC and -D are more evenly distributed between seeds, pulp and skin, while VvLOXO is mostly expressed in the seed. Mechanical wounding and infection of berries with Botrytis cinerea Pers.: Fr resulted in rapid accumulation of VvLOXC and -O transcripts. VvLOXA expression decreased in diseased berries. Biochemical analysis of VvLOXA and -O recombinant proteins confirmed that these LOX genes encode functional 13-LOXs that exhibit different pH and temperature optima. Both enzymes showed activity with linoleic, linolenic and arachidonic acids.
Estimating the population size of a threatened arboreal marsupial: use of distance sampling to dispense with ad hoc survey techniques
Authors: de Tores Paul J. , Elscot Sue
Published: October 2010

Context. Long-term land-use decisions potentially affecting the conservation status of rare fauna are often based on a dearth of relevant biological information and population estimates are regularly derived from ad hoc methodologies. This can significantly affect the outcomes from development assessment and approval processes. Aim. Our aims were to apply distance-sampling techniques to derive robust, quantitative estimates of the population size of a threatened arboreal marsupial, the western ringtail possum (Pseudocheirus occidentalis Thomas, 1888), demonstrate the advantages of this approach and, in doing so, provide conservation managers, decision makers and consultants with a reliable framework for surveying the species. Methods. We used line-transect sampling to derive estimates of density and abundance for P. occidentalis at two sites in south-western Western Australia where estimates were previously derived through ad hoc techniques. Key results. Our findings support the assertion that previous surveys of P. occidentalis populations have underestimated the population size to a varying extent at both of our survey sites. Land-use and development-application decisions have previously been based on similar surveys. Conclusions. Distance sampling, if applied routinely when surveying P. occidentalis, will reduce the uncertainty associated with derived estimates of abundance. Implications. Appropriate use of distance-sampling methods will enable managers and decision makers to assess more quantitatively the potential effect from, and place appropriate approval conditions on, proposals that modify or destroy P. occidentalis habitat. The use of the program Distance will enable such decisions to be based on robust, repeatable estimates of population size, with quantified confidence limits and variance estimates.
Evidence for a bimodal distribution in human communication
Authors: Wu Ye , Zhou Changsong , Xiao Jinghua , Kurths Jürgen , Schellnhuber Hans Joachim
Published: October 2010

Interacting human activities underlie the patterns of many social, technological, and economic phenomena. Here we present clear empirical evidence from Short Message correspondence that observed human actions are the result of the interplay of three basic ingredients: Poisson initiation of tasks and decision making for task execution in individual humans as well as interaction among individuals. This interplay leads to new types of interevent time distribution, neither completely Poisson nor power-law, but a bimodal combination of them. We show that the events can be separated into independent bursts which are generated by frequent mutual interactions in short times following random initiations of communications in longer times by the individuals. We introduce a minimal model of two interacting priority queues incorporating the three basic ingredients which fits well the distributions using the parameters extracted from the empirical data. The model can also embrace a range of realistic social interacting systems such as e-mail and letter communications when taking the time scale of processing into account. Our findings provide insight into various human activities both at the individual and network level. Our analysis and modeling of bimodal activity in human communication from the viewpoint of the interplay between processes of different time scales is likely to shed light on bimodal phenomena in other complex systems, such as interevent times in earthquakes, rainfall, forest fire, and economic systems, etc.
The Brain Is Both Neurocomputer and Quantum Computer
Authors: Hameroff Stuart R.
Published: October 2010

In their article, Is the Brain a Quantum Computer,? criticize the Penrose–Hameroff “Orch OR” quantum computational model of consciousness, arguing instead for neurocomputation as an explanation for mental phenomena. Here I clarify and defend Orch OR, show how Orch OR and neurocomputation are compatible, and question whether neurocomputation alone can physiologically account for coherent gamma synchrony EEG, a candidate for the neural correlate of consciousness. Orch OR is based on quantum computation in microtubules within dendrites in cortex and other regions linked by dendritic–dendritic gap junctions (“dendritic webs”) acting as laterally connected input layers of the brain's neurocomputational architecture. Within dendritic webs, consciousness is proposed to occur as gamma EEG‐synchronized sequences of discrete quantum computational events acting in integration phases of neurocomputational “integrate‐and‐fire” cycles. Orch OR is a viable approach toward understanding how the brain produces consciousness.