bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nonrigid motion correction in 3D using autofocusing withlocalized linear translations
Authors: Cheng Joseph Y. , Alley Marcus T. , Cunningham Charles H. , Vasanawala Shreyas S. , Pauly John M. , Lustig Michael 
Published: February 2012

AbstractMR scans are sensitive to motion effects due to the scan duration. To properly suppress artifacts from nonrigid body motion, complex models with elements such as translation, rotation, shear, and scaling have been incorporated into the reconstruction pipeline. However, these techniques are computationally intensive and difficult to implement for online reconstruction. On a sufficiently small spatial scale, the different types of motion can be well approximated as simple linear translations. This formulation allows for a practical autofocusing algorithm that locally minimizes a given motion metric — more specifically, the proposed localized gradient‐entropy metric. To reduce the vast search space for an optimal solution, possible motion paths are limited to the motion measured from multichannel navigator data. The novel navigation strategy is based on the so‐called “Butterfly” navigators, which are modifications of the spin‐warp sequence that provides intrinsic translational motion information with negligible overhead. With a 32‐channel abdominal coil, sufficient number of motion measurements were found to approximate possible linear motion paths for every image voxel. The correction scheme was applied to free‐breathing abdominal patient studies. In these scans, a reduction in artifacts from complex, nonrigid motion was observed. Magn Reson Med, 2012. © 2012 Wiley Periodicals, Inc.
Thiol‐ene/clay nanocomposite thin film as novel transparent barrier
Authors: Bae Joonwon 
Published: February 2012

AbstractThiol‐ene/clay (TE/clay) nanocomposite thin films were prepared by a simple photocuring process for use as transparent barrier films. In this work, tetrafunctional thiol and triene monomer were employed and organic clay surface modified with octadecylamine was mixed by sonication and a mechanical method as a reinforcing filler. The successful formation of the TE structure was confirmed by differential scanning calorimetry and X‐ray diffraction. The homogeneous dispersion (intercalation and exfoliation) of clay into the TE polymer matrix was observed with transmission electron microscopy. Atomic force microscopy images displayed the surface properties of the TE/clay nanocomposite thin films. The thermal expansion behavior of the resulting hybrid film was monitored by thermomechanical analysis. In addition, gas permeation properties as well as light transmittance of the TE/clay films were measured for potential applications in various fields as dimensionally stable films under heating and as a transparent barrier. Copyright © 2012 Society of Chemical Industry
Towards ultrathin copper indium gallium diselenide solar cells: proof of concept study by chemical etching and gold back contact engineering
Authors: Li‐Kao Zacharie Jehl , Naghavi Negar , Erfurth Felix , Guillemoles Jean François , Gérard Isabelle , Etcheberry Arnaud , Pelouard Jean Luc , Collin Stephane , Voorwinden Georg , Lincot Daniel 
Published: February 2012

ABSTRACTAn innovative approach combining chemical etching and a “lift‐off” process, which allows back contact processing after CIGSe deposition, permitted to use Au as a highly reflective back contact in ultrathin CIGSe solar cells. The Au back contact does not degrade the other parameters of the cell, as good ohmicity on CIGSe is achieved. An important photocurrent increase compared with regular Mo back contact solar cells is achieved by the enhanced light trapping effect due to the back reflector, leading to an absolute efficiency increase of +2.5% for a CIGSe thickness of 0.4 µm. This approach could be used for further investigations in improving the back side of ultrathin CIGSe solar cells. Copyright © 2012 John Wiley & Sons, Ltd.
Large electro‐optic activity and enhanced temporal stability of methacrylate‐based crosslinking hyperbranched nonlinear optical polymer
Authors: Mori Yuichi , Nakaya Kosei , Piao Xianqing , Yamamoto Kazuhiro , Otomo Akira , Yokoyama Shiyoshi 
Published: February 2012

AbstractA methacrylate‐based crosslinking hyperbranced polymers have been synthesized through initiator‐fragment incorporation radical polymerization and used for the temperature stable electro‐optic (EO) polymer application. This polymer consists of methyl methacrylate, 2‐metacryloxyethyl isocyanate, and ethylene glycol dimethacrylate (EGDMA) monomers. The use of EGDMA as a bifunctional unit resulted in the solvent‐soluble crosslinking hyperbranched chain, so that the EO polymer enhanced glass transition temperatures. A phenyl vinylene thiophene vinylene bridge nonlinear optical chromophore was attached to the polymer backbone as the side‐chain by a post‐functionalization reaction. The loading concentration of the chromophore was varied between 30 and 50 wt % by simply changing the mixing ratio of the precursor polymer to the chromophore. The synthesized EO polymers produced optical quality films with a light propagation loss of 0.61 dB/cm in a slab waveguide at 1.31 μm. The electrically poled film had an EO coefficient (r33) of 139 pm/V at 1.31 μm. The EO crosslinking hyperbranced polymer had a high‐glass transition temperature of 170 °C, and exhibited excellent temporal stability of the EO activity at 85 °C for 500 h. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Assessing health‐related quality of life of Chinese‐American breast cancer survivors: a measurement validation study
Authors: Ashing‐Giwa Kimlin , Lam Chun Nok , Xie Bin 
Published: February 2012

AbstractBackgroundThis study reports on the internal consistency and construct validity of the Functional Assessment of Cancer Therapy – General (FACT‐G v.4) and 12‐item Short Form Health Survey (SF‐12 v.2) health‐related quality of life (HRQOL) instruments with Chinese‐American breast cancer survivors (BCS).MethodsParticipants completed mailed questionnaires at baseline and 12‐month follow‐up. HRQOL was measured using the FACT‐G and the SF‐12. The measures were evaluated by construct validity and reliability tests. Factor analyses were performed in a two‐wave assessment through exploratory and confirmatory analyses at baseline and follow‐up.ResultsSeventy‐four Chinese‐American BCS participated. Excellent internal consistency (α > 0.85) and good construct validity for the FACT‐G (five factors) and the SF‐12 (two factors) were observed. Factor structure of both measures accounted for 70% of the common variance in physical, social/family, emotional, and functional well‐being subscales for the FACT‐G and in physical and mental components for the SF‐12.ConclusionsOur data demonstrated good internal consistency and construct validity of the measures. The psychometric findings demonstrate the utility of the FACT‐G and the SF‐12 to assess HRQOL among Chinese‐American BCS. Copyright © 2012 John Wiley & Sons, Ltd.
Holographic quark‐gluon plasmas at finite quark density
Authors: Bigazzi F. , Cotrone A. , Mas J. , Tarrio J. , Mayerson D. 
Published: February 2012

AbstractGravity solutions holographically dual to strongly coupled Quark‐Gluon Plasmas with non‐zero quark density are reviewed. They are motivated by the urgency of finding novel tools to explore the phase diagram of QCD‐like theories at finite chemical potential. After presenting the solutions and their regime of validity, some of their physical properties are discussed.
A joint effect of new western diet and retinoid X receptor alpha prostate‐specific knockout with development of high‐grade prostatic intraepithelial neoplasia in mice—A preliminary study
Authors: Mao Gloria E. , Harris Diane M. , Moro Aune , Heber David , Roy‐Burman Pradip , Zhang Zuo‐Feng , Rao Jianyu 
Published: February 2012

AbstractBACKGROUNDThe “New Western‐style Diet” (NWD) characterized by high in fat and low in fiber, vitamin D, calcium, and methyl donors—are considered as a risk factor for prostate cancer. Previous studies have shown that premalignant lesions of human prostate have decreased expression of the Retinoid X Receptor alpha (RXRα). This study was to determine the effect of diet in RXRα knockout mice in developing high‐grade prostate intraepithelial neoplasia (mPIN).METHODSMale mice (n = 54) with or without the RXRα prostate null mutation were fed either NWD or AIN‐76A control diet for 10 months; prostates were harvested at 11 months of age and examined for prostate mPIN.RESULTSmPIN was seen in 79% of RXRα prostate null mice fed NWD (n = 19), 30.8% RXRα prostate null mice fed AIN‐76A (n = 13), 42.9% RXRα wild‐type mice fed NWD (n = 14), and 12.5% RXRα wild‐type mice fed AIN‐76A (n = 8). Unconditional Logistic analysis showed a significant joint effect of NWD and RXRα status in developing mPIN 26.3 (95% CI: 2.5–280), but interaction was not significant owing to the small sample size 1.6 (0.09–27.7, P = 0.7441).CONCLUSIONThis study provides preliminary data to support a joint RXRα‐diet effect in prostate carcinogenesis. Prostate 72:1052–1059, 2012. © 2012 Wiley Periodicals, Inc.
Interactions between the root pathogen Rhizoctonia solani AG‐8 and acetolactate‐synthase‐inhibiting herbicides in barley
Authors: Lee Hyejin , Ullrich Steven E , Burke Ian C , Yenish Joseph , Paulitz Timothy C 
Published: February 2012

AbstractBACKGROUND: The widespread acceptance of reduced‐tillage farming in cereal cropping systems in the Pacific Northwest of the United States has resulted in increased use of herbicides for weed control. However, soil residual concentrations of widely used imidazalone herbicides limit the cultivation of barley, which is more sensitive than wheat. In addition, increased severity of the root rot disease caused by Rhizoctonia solani is associated with reduction in tillage. Many crops exhibit altered disease responses after application of registered herbicides. In this study, the injury symptoms in barley caused by sublethal rates of two acetolactate synthase (ALS)‐inhibiting herbicides, imazamox and propoxycarbazone‐sodium, were assessed in factorial combinations with a range of inoculum concentrations of the root rot pathogen Rhizoctonia solani AG‐8.RESULTS: Both herbicides and pathogen had negative impacts on plant growth parameters such as root and shoot dry weight, shoot height and first leaf length, and interactions between pathogen and herbicide were detected.CONCLUSIONS: The results suggested that sublethal rates of herbicides and R. solani could alter severity of injury symptoms, possibly owing to the herbicide predisposing the plant to the pathogen. Copyright © 2012 Society of Chemical Industry
Raman scattering characterization of ZnSe/Zn0.6Cd0.4Se multilayers prepared by thermal vacuum evaporation
Authors: Nesheva Diana , Šćepanović Maja , Aneva Zdravka , Levi Zelma , Popović Zoran V. , Miloushev Ilko 
Published: February 2012

AbstractNanocrystalline multilayers from ZnSe/Zn0.6Cd0.4Se with three different layer thicknesses (3.5, 5.0, 10.0 nm) and, for comparison, 400 nm thick Zn0.6Cd0.4Se nanocrystalline single layers have been prepared by thermal evaporation of ZnSe and CdSe in vacuum. Raman scattering spectra have been measured in the range 100–1000 cm−1 under excitation with the 488 and 514.5 nm lines of an Ar+ laser. Series of four bands have been seen in the spectra of all samples. They have been related to replicas of the longitudinal optical LO‐phonon in the ZnxCd1−xSe layers and interpreted as an indication for crystallinity of both kinds of samples. A blue shift of the 1 LO maximum has been observed, which has been connected with an increase of the compressive stress in the ternary layers when the layer thickness decreases. It has also been obtained that the ratio of the integrated intensity of the 1 LO band in the spectra taken with the 488 and 514.5 nm lines decreases with decreasing Zn0.6Cd0.4Se layer thickness. The result has been assigned to size‐induced increase of the optical band gap of the layers. This conclusion has been confirmed by spectral photocurrent and optical transmission measurements.
Properties of ultraviolet anti‐Stokes photoluminescence in ZnO single crystals
Authors: Fujii Katsushi , Goto Takenari , Yao Takafumi 
Published: February 2012

AbstractUltraviolet (UV) anti‐Stokes photoluminescence (ASPL) was observed in ZnO single crystals at low temperature. The ASPL spectrum was essentially the same as the normal photoluminescence (PL) spectrum under excitation in the band to band transition. By analogy to the ASPL of GaN, a two‐step two‐photon absorption process is suggested to occur in ZnO. The ratio of re‐excited electrons in the intermediate state is, however, smaller than that for GaN from the excitation intensity dependence of the ASPL. This difference is probably due to the carrier lifetime of the intermediate state for ZnO being shorter than that for GaN.
Optical parametric oscillaton in 1D semiconductor microcavities
Authors: Ardizzone Vincenzo , Abbarchi Marco , Lecomte Timothee , Lemaitre Aristide , Sagnes Isabelle , Senellart Pascale , Bloch Jacqueline , Roussignol Philippe , Tignon Jerome 
Published: February 2012

AbstractWe present an experimental investigation of parametric scattering processes and optical parametric oscillations in wire shaped, one‐dimensional semiconductor microcavities. Far field emission patterns and corresponding band dispersion are studied by polarization resolved measurements and power dependence measurements under resonant and non‐resonant excitation. The multiplicity of the photonic bands allows for an efficient engineering of interbranch parametric scattering processes. We demonstrate the onset of optical parametric oscillation of perfectly balanced twin beams, degenerate in energy and split in momentum space.
Carrier dynamics in active regions for ultraviolet optoelectronics grown on thick, relaxed AlGaN on semipolar bulk GaN
Authors: Garrett Gregory A. , Rotella Paul , Shen Hongen , Wraback Michael , Haeger Daniel A. , Chung Roy B. , Pfaff Nathan , Young Erin C. , DenBaars Steven P. , Speck James S. , Cohen Daniel A. 
Published: February 2012

AbstractActive regions for mid‐ultraviolet laser diodes grown on bulk AlGaN templates are investigated by time‐resolved photoluminescence. The active regions were grown pseudomorphically on thick, relaxed AlGaN on bulk GaN in the semi‐polar ($20{\bar {2}}1$) orientation where it has been shown that the glide of dislocations create strain relieving defects confined to the AlGaN/GaN interface, away from the active region. The photoluminescence lifetimes were found to have mono‐exponential decays of around 500 ps and calculated radiative and non‐radiative lifetimes are compared to previously reported results for active regions on bulk m‐plane GaN.
Electron scattering on the short‐range potential of crystal lattice defects in gallium nitride
Authors: Malyk Orest 
Published: February 2012

AbstractThe processes of the charge carrier scattering on the short‐range potential caused by interaction with polar and nonpolar optical phonons, piezoelectric and acoustic phonons, static strain, neutral and ionized impurities in wurtzite n‐GaN with impurity concentration 4×1016–2×1019 cm‐3 are considered. The temperature dependences of electron mobility in the range 40–500 K are calculated. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Plasma‐assisted electroepitaxy as a novel method for the growth of GaN layers
Authors: Novikov S. V. , Staddon C. R. , Powell R. E. L. , Akimov A. V. , Kent A. J. , Foxon C. T. 
Published: February 2012

AbstractIn the current study we have demonstrated the feasibility of a novel approach for the growth of GaN layers, namely plasma‐assisted electroepitaxy (PAEE). In this method, we have combined the advantages of the plasma process for producing high concentrations of active N species in the Ga melt with the advantages of electroepitaxy in transferring the N species from the Ga surface to the growth interface, without spontaneous crystallisation on the surface or within the solution. We have designed and built a new growth chamber which allows us to combine the plasma‐assisted molecular beam epitaxy process with a liquid phase electroepitaxy system. We have demonstrated that it is possible to grow GaN layers by PAEE at growth temperatures as low as ∼650 oC and with low nitrogen overpressures of ∼3×10‐5 Torr. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Normally‐off AlGaN/GaN power tunnel‐junction FETs
Authors: Chen Hongwei , Yuan Li , Zhou Qi , Zhou Chunhua , Chen Kevin J. 
Published: February 2012

AbstractWe present normally‐off AlGaN/Gan power tunnel‐junction FETs (TJ‐FETs) with high breakdown voltage, low off‐state leakage current and low specific on‐resistance. The TJ‐FETs exhibit normally‐off operation in an otherwise normally‐on as‐grown sample owing to a current controlling scheme different from the conventional FETs. The high 2DEG density in AlGaN/GaN heterostructure results in a thin tunnel barrier whose effective thickness is controlled by an overlaying gate electrode. This tunnel junction is controlled by an overlapping gate and deliver highly efficient quantum tunnelling, enabling normally‐off operation. A positive gate bias results in a nanometer‐thick barrier with high tunnelling current, while a zero gate bias leads to a thicker barrier that effectively blocks the current flow. High tunnel current (326 mA/mm), low off‐state leakage (10‐8 mA/mm) and high off‐state breakdown voltage (557 V) are obtained on a standard GaN‐on‐Si platform featuring a 1.8 μm buffer. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
High nitrogen pressure solution growth of GaN in multi feed‐seed configuration
Authors: Bockowski M. , Lucznik B. , Sochacki T. , Sadovyi B. , Nowak G. , Litwin‐Staszewska E. , Grzegory I. 
Published: February 2012

AbstractThe results of High Nitrogen Pressure Solution (HNPS) growth of GaN in multi feed‐seed (MFS) configuration are presented. The idea of this configuration is based on the conversion of the free standing HVPE‐GaN crystals (seeds) to the free standing HNPS‐GaN of much higher quality than the seeds. A new arrangement of the seeds in the MFS configuration is shown. The influence of the experimental conditions (i.e. growth temperature, temperature gradient) on the growth rate, growth mode and electrical properties of HNPS‐GaN is presented. The regrowth procedure is introduced in order to increase the lattice bowing radii of the HNPS‐GaN crystals and finally obtain crystalographically flat (bowing radius of 30 meters) pressure grown GaN substrates (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optical studies of quantum dot‐like emission from localisation centres in InGaN/GaN nanorod array LEDs
Authors: Chan Christopher C. S. , Shields Philip A. , Holmes Mark J. , Zhuang YiDing , Wang Xu , Reid Benjamin P. L. , Kim HeeDae , Allsopp Duncan W. E. , Taylor Robert A. 
Published: February 2012

AbstractMicrophotoluminescence with one‐photon and two‐photon excitation has been employed to investigate localisation centres found in nanorod array LEDs. Quantum dot‐like features with spectral width less than 1 meV were observed originating from low dimensional carrier confinement within the nanorods. Two‐photon excitation was used to probe the individual localisation centres. The narrow peak PL energy does not shift with increasing excitation density, but rather an increase of discrete new peaks on the high energy side of the spectrum is observed. There is no temperature dependent emission energy shift observed from 4.3 K to 25 K. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Phase diagram on phase purity of InN grown pressurized‐reactor MOVPE
Authors: Kimura Takeshi , Prasertsuk Kiattiwut , Zhang Yuantao , Liu Yuhuai , Hanada Takashi , Katayama Ryuji , Matsuoka Takashi 
Published: February 2012

AbstractInN epitaxial films are directly grown on sapphire (0001) substrates by using Pressurised‐Reactor metalorganic vapour phase epitaxy (PR‐MOVPE) system originally developed by ourselves. This system makes it possible to control the side wall of islands perpendicular to the substrate surface, which is important in the heteroepitaxial growth with large lattice‐mismatch from the analogy of the GaN growth on sapphire substrates. This high pressure also leads to the growth at the higher temperature than that at the atmospheric pressure. In this paper, InN films are grown by PR‐MOVPE at 2,400 Torr. Its polarity is nitrogen one, which has the superior efficiency to indium polarity in the capture of nitrogen at the growth front. To crystallographically identify films using the diffractions from sapphire (006), wurtzite (WZ) InN (002), zincblende (ZB) InN (111) and metallic indium (101), 2θ–ω scans and the pole figure measurements in X‐ray diffraction are measured. From the pole figure measurements, the orientation and crystalline phases of grains in crystals are determined. The phase diagram between trimethylindium as an indium source flow rate and the growth temperature is drawn. The regions with pure WZ InN and with the incorporation of ZB phase and the metallic indium into WZ phase and the metal‐indium are observed. It is also observed that the grains with WZ phase have c‐axis normal to the (111) plane at the side wall of the ZB grains. Finally, the growth conditions for pure WZ InN make it clear by using PR‐MOVPE. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Enhancement‐mode m ‐plane AlGaN/GaN HFETs with regrown n+‐GaN contact layer
Authors: Fujiwara Tetsuya , Keller Stacia , Speck James S. , DenBaars Steven P. , Mishra Umesh K. 
Published: February 2012

AbstractHigh performance enhancement‐mode m ‐plane AlGaN/GaN heterojunction field‐effect transistors were reported in this letter. +3 V threshold voltages, 230 mA/mm of maximum drain‐source current (Ids(max)), and 58 mS/mm of maximum transconductance (gm(max)) were obtained. High Ids(max) and gm(max) were due to the regrown n+‐GaN contact layer. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Anti‐corrosive stainless steel separator coated with MOCVD InGaN for polymer electrolyte fuel cell (PEFC)
Authors: Shimahashi M. , Matsui K. , Okada K. , Sugita K. , Sasaki H. , Yamamoto A. 
Published: February 2012

AbstractThis paper reports the application of InGaN films to a polymer electrolyte cells (PEFC) stainless steel (SS) separator for the first time. Using MOCVD, InGaN films with In content of 0‐1 are grown at 600 °C on sapphire and stainless steel substrates. Sputtered TiN is used as a buffer for the InGaN growth on stainless steel. For InGaN on sapphire substrates, electrical resistivity and dissolution rate in a H2SO4 solution at 60 °C are measured, and films with In content in the range 0.2‐0.5 are found to have both high electric conductivity and high corrosion resistance. The anti‐corrosive properties of In0.3Ga0.7N/TiN/SS structures are also confirmed by the inductively coupled plasma spectrometry (ICP) chemical analysis of the H2SO4 solution in which the In0.3Ga0.7N/TiN/SS samples are dipped for 100 h. The levels of both Ga and In atoms are under the detection limits. The I‐V characteristics of a single cell using an In0.3Ga0.7N/TiN/SS separator is measured in comparison with those using bare stainless steel or carbon separators. The performance of the cell with the In0.3Ga0.7N/TiN/SS separator is much superior to that with a bare stainless steel. Compared with the cell using the carbon separator, the cell using the In0.3Ga0.7N/TiN/SS separator has a little larger ohmic loss (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)