bluuebunny/crossref_metadata_2025 huggingface dataset:
Radio-Frequency Downstream Plasma Production by Surface-Wave in a Very High-Permittivity Material Discharge Tube
Authors: Fujiwara Kazuya , Endo Masakatsu , Ikeda Yasushi , Suzuki Tsutomu , Yanagisawa Michihiko , Shindo Haruo
Published: July 2005

A novel method of radio-frequency surface-wave plasma production is proposed, with a particular interest in use of a very high permittivity material discharge tube. A discharge tube of TiCa-TiMg composite, which has the permittivity of 140, is employed to produce SF6 plasma by the 13.56 MHz radio-frequency power. The axial distribution of optical emission lines of fluorine shows a rapid decay, more than 5 times faster than that in quartz tube. This is because the speed of the surface-wave is reduced in a condition of very high permittivity. It is concluded that the method is innovative in use of radio-frequency power to produce downstream plasma with a very high permittivity discharge tube.
Alignment-Free Top-Contact Formation for Organic Thin Film Transistors with Submicron-Length Channel
Authors: Yagi Iwao , Shigeto Kunji , Tsukagoshi Kazuhito , Aoyagi Yoshinobu
Published: July 2005

We propose a simple fabrication method for self-aligned top contacts for an organic thin film transistor (TFT) that can be miniaturized. The self-aligned top electrodes are formed without any break in the vacuum condition after the formation of an organic channel on the substrate with a prefabricated insulating structure. As a demonstration of this method, pentacene TFTs with submicron-length channels have been fabricated and successfully operated. Scanning electron microscopy of TFTs reveals well-defined TFT structures as expected.
Brilliant Blue Observation from a Morpho-Butterfly-Scale Quasi-Structure
Authors: Watanabe Keiichiro , Hoshino Takayuki , Kanda Kazuhiro , Haruyama Yuichi , Matsui Shinji
Published: July 2005

The Morpho-butterfly wing reflects interfered brilliant blue, which originates from nanostructures on its scales, for any incidence angle of white light. We have, for the first time, fabricated a Morpho-butterfly-scale quasi-structure using focused-ion-beam chemical-vapor-deposition (FIB-CVD) and observed brilliant blue reflection from this quasi-structure with an optical microscope. We measured the reflection from real Morpho-butterfly scales and from the quasi-structure with a photonic multi-channel spectral analyzer system. The reflection spectra of the quasi-structure were very similar to those of Morpho-butterfly scales.
Single-Walled Carbon Nanotube Thin-Film Sensor for Ultrasensitive Gas Detection
Authors: Wongwiriyapan Winadda , Honda Shin-ichi , Konishi Hirofumi , Mizuta Tomoaki , Ikuno Takashi , Ito Tatsuya , Maekawa Toru , Suzuki Kengo , Ishikawa Hiroshi , Oura Kenjiro , Katayama Mitsuhiro
Published: July 2005

We demonstrated a gas sensor fabricated by growing a single-walled carbon nanotube (SWNT) thin film directly on a conventional sensor substrate. NO2 and Cl2 were detected down to the ppb level under room-temperature operation with a fast response. Using an electrical breakdown technique, gas response sensitivity was improved by an order of magnitude. The relationship between gas concentration and sensor response was derived based on the Langmuir adsorption isotherm, predicting a detection limit of 8 ppb for NO2. The SWNT thin-film gas sensor exhibits merits over other types of sensors by virtue of its simplicity in fabrication and feasible application.
Effects of Homoepitaxial GaAs/GaAs and Heteroepitaxial GaAs/Si Solar Cells after 1 MeV Electron Irradiation for Space Application
Authors: Chandrasekaran Nallathambi , Soga Tetsuo , Inuzuka Yousuke , Taguchi Hironori , Jimbo Takashi , Imaizumi Mitsuru
Published: July 2005

The high-energy electron irradiation effect of GaAs solar cells on Si substrate has been described and the results were compared with GaAs solar cell on GaAs substrates. The solar cells were irradiated with 1 MeV electron in the range of fluences from 1 ×1013 cm-2 to 1 ×1016 cm-2. The solar cell parameters such as short-circuit current (I
sc), open circuit-voltage (V
oc) and conversion efficiency were studied under dark and AM 0 conditions. The degradation rate of V
oc and P
max of GaAs/GaAs solar cell is faster than GaAs/Si solar cell after the fluences higher than 1015 cm-2. The slow degradation of GaAs/Si solar cell has been attributed to slow generation of As vacancy.
Shapiro Step Response of the Surface Intrinsic Josephson Junctions in Bi2Sr2CaCu2Oy Single Crystals at Elevated Temperatures
Authors: Oya Gin-ichro , Terada Atsushi , Takahashi Nobuyuki , Irie Akinobu , Hashimoto Taizo
Published: July 2005

We study the temperature dependent features of surface intrinsic Josephson junctions in the mesas of Bi2Sr2CaCu2O
y
single crystals and the Shapiro step response to injection of microwave in a frequency f
rf range of 2–20.5 GHz of the junctions at elevated temperatures. This junction is characterized by the suppressed critical current I
c and plasma frequency f
pl, which may be due to a decrease in the Josephson coupling depending on the modulated structure in it. Its Shapiro step response is observed up to 45.5 K by controlling thermally its I
c and hence f
pl so as to satisfy f
pl<f
rf.
Noninvasive Measurements of Magnetic Field Generated by Induced Current within Human Body under Exposure to Very Low Frequency Electromagnetic Fields
Authors: Tsukada Keiji , Kiwa Toshihiko
Published: July 2005

We have developed a measurement system for a magnetic field that is generated by the induced ionic current within the human body under exposure to very low frequency electromagnetic fields, and compared the magnetic field strength obtained with those of a magnetomyogram (MMG). The developed system consists of an exposure coil, a magnetic sensor, a lock-in detector, and data acquisition. The waveform characteristics of the magnetic field of the induced current (MFIC) of the abdomen from 1 kHz to 400 Hz are obtained. Compared with the magnetic field strength of abdominal MMG, abdominal MFIC is stronger at an exposure electromagnetic field greater than the µT order.
Absorption Saturation Energy Density of InGaAs-InAlAs Multiple Quantum Well under Tensile and Compressive Strain
Authors: Okuno Tsuyoshi , Masumoto Yasuaki , Higuchi Akira , Yoshino Hideo , Bando Hiroyuki , Okamoto Hiroshi
Published: July 2005

Optical absorption saturation density I
s was measured for In
x
Ga1-x
As-In0.52Al0.48As multiple quantum well structures grown on InP (100) substrates by molecular beam epitaxy. Indium composition x was varied from 0.32 to 0.70 so that the quantum well layer was under tensile strain (x < 0.53), lattice matched (x = 0.53), or compressive strain (x > 0.53). Optical measurement was carried out using femtosecond light pulses from the optical parametric amplifier of a mode-locked Ti-sapphire laser amplifier. The density I
s in a sample changed as a function of photon energy and exhibited a minimum value at the band-edge exciton energy. This minimum I
s showed the smallest value at x=0.46 (under tensile strain) of all the samples with different x. This was in marked contrast to the results reported in the literature. Degenerate pump-probe measurement was also carried out, and the results showed that the relative transmission change ΔT/T measured at zero delay between the pump and probe pulses exhibited the largest value at x=0.46, confirming the result of I
s measurement.
Impact of Defect Control on the Polarization Properties in Bi4Ti3O12 Ferroelectric Single Crystals
Authors: Noguchi Yuji , Matsumoto Takahiro , Miyayama Masaru
Published: July 2005

We have investigated the defect structure in bismuth titanate (Bi4Ti3O12) through high-temperature neutron powder diffraction analysis and ab-initio electronic structure calculations. It is shown that the vacancies of Bi and oxide ions are created preferentially in the perovskite layers rather than in the Bi2O2 layers. Measurements of the leakage-current properties of the single crystals demonstrate that electron holes arising from the incorporation of oxygen at the vacancies of oxide ions act as detrimental carriers for electrical conduction at room temperature. A crystal growth under high oxygen pressure is proposed to be advantageous for suppressing the vacancy formation and for attaining a large remanent polarization as well as a high insulating property of the Bi4Ti3O12 system.
Iodine Solid Source Inductively Coupled Plasma Etching of InP
Authors: Matsutani Akihiro , Ohtsuki Hideo , Koyama Fumio
Published: July 2005

We have demonstrated vertical and smooth inductively coupled plasma (ICP) dry etching of InP using solid iodine as a gas source at a low process temperature of 90°C. We prepared a solid iodine crystal in the ICP etching chamber as the etching gas source. Iodine gas was supplied from the solid source at a high vapor pressure into the process chamber. Vertical and smooth etching was realized under the condition of low temperature and low power. The typical etching rate was 0.4 µm/min. We believe that solid I2-ICP etching is a very simple and useful process for InP-based device fabrication with a resist mask.
Vacancy Formation Energy at Metal-Silicon Interface Region
Authors: Suezawa Masashi , Saitoh Kesami , Kojima Ken-ichi , Kasuya Atsuo
Published: July 2005

We studied the vacancy formation energy in silicon crystals evaporated with various metals. Specimens were cut out from a high-purity FZ. Si crystal. They were evaporated with various metals and heated in hydrogen gas followed by quenching in water. Instead of vacancy (V) concentration, we measured the optical absorption coefficient due to VH4, which is a complex of one V and four H atoms. The vacancy formation energy in these specimens was found to be much smaller than that in high-purity specimens and that in specimens doped with metallic impurities in an isolated state (solid solution). Moreover, after heating for a short time, the vacancy concentration exhibited a spatial distribution decreasing with distance from the interface, which suggests that the vacancy source is the interface region.
Femtosecond-Laser-Assisted Chemical Vapor Deposition of Cr Metal
Authors: Hitosugi Taro , Mizuno Takeshi
Published: July 2005

Focused femtosecond lasers have been used to deposit Cr lines by the nonlinear excitation of Cr(CO)6 on the surfaces of BK7 glass, soda glass and Cr thin films. Cr lines with a linewidth of 570 nm, which is beyond the diffraction limit, were deposited on BK7 glass. The surface morphology of the deposits were found to be sensitive not only to a fluence of laser pulses but also to the numerical apertures of various objective lenses.
Fabrication of Organic Electroluminescence Device with Ion Beam-Assisted Deposition of Ultrathin Lithium Fluoride as a Hole Injection Layer
Authors: Choi Sang Hun , Jeong Soon Moon , Koo Won Hoe , Baik Hong Koo
Published: July 2005

An ultrathin lithium fluoride (LiF) hole injection layer was deposited on an indium-tin-oxide (ITO) anode by an ion-beam-assisted deposition (IBAD) technique to fabricate an organic electroluminescence device. The device with the LiF layer deposited by this method has higher external quantum efficiency than a device with a LiF deposited by conventional thermal evaporation. Moreover, the hole-injection ability of the device prepared by IBAD is better than that of the device produced by a conventional method such as thermal evaporation. It is found that the surface of the LiF layer prepared by IBAD has high surface coverage on an ITO anode because the LiF layer prepared has high adatom mobility due to the ion beam energy.
The Interface between Single Crystalline (001) LaAlO3 and (001) Silicon
Authors: Klenov Dmitri O. , Schlom Darrell G. , Li Hao , Stemmer Susanne
Published: July 2005

Atomic resolution high-angle annular dark-field imaging in scanning transmission electron microscopy is used to determine atomic arrangements at LaAlO3/Si interfaces, which were obtained by growing Si films epitaxially on (001) LaAlO3 single crystals. An unusual 3 ×1 interface reconstruction, in which every third La column is removed from the interface plane, is observed. The interface atomic structure is discussed in the context of electrically favorable interfacial bonding between the ionic oxide and Si.
Single-Photon Generation in the 1.55-µm Optical-Fiber Band from an InAs/InP Quantum Dot
Authors: Miyazawa Toshiyuki , Takemoto Kazuya , Sakuma Yoshiki , Hirose Shinichi , Usuki Tatsuya , Yokoyama Naoki , Takatsu Motomu , Arakawa Yasuhiko
Published: July 2005

We first succeeded in generating single-photon pulses in the C-band (1.55-µm band: the highest transmittance in optical telecommunication bands) from a single InAs/InP quantum dot. The quantum dot with 1546.1-nm exciton emission was prepared by controlling the growth conditions. A well-designed mesa structure presented efficient injection of the emitted photons into a single-mode optical fiber. A Hanbury-Brown and Twiss measurement has proved that the photons through the fiber were single photons. We also performed to transmit single-photon pulses through 30-km optical fiber. This preliminary trial is a milestone toward quantum telecommunication using ideal single photons.
Effects of Axial Magnetic Field on Neutral Beam Etching by Low-Angle Forward-Reflected Neutral Beam Method
Authors: Lee Dohaing , Park ByungJae , Yeom Geunyoung
Published: July 2005

A low axial magnetic field was applied to an inductively coupled plasma (ICP) ion source used to generate a neutral beam for a low-angle forward-reflected neutral (LAFRN) beam system, and its effects on the ICP ion source and the features of Si and SiO2 etching using the LAFRN beam system for SF6 gas were investigated. As a result of applying a low axial magnetic field of approximately 20 G, a significant increase in SF3
+ ion flux extracted from the source was observed among the various reactive ions generated using SF6 gas, and the etch rates of Si and SiO2 using a neutral beam formed by the magnetically enhanced SF6 ICP source were also increased. The application of the low axial magnetic field also improved the etch uniformity of the neutral beam etching system.
Characterization of Two-Photon Absorption Related to the Enhanced Bulk Damage Resistance in CsLiB6O10 Crystal
Authors: Kamimura Tomosumi , Nakamura Ryosuke , Horibe Hideo , Nishioka Munenori , Yamamoto Masashi , Yoshimura Masashi , Mori Yusuke , Sasaki Takatomo , Yoshida Kunio
Published: July 2005

Two-photon absorption of CsLiB6O10 (CLBO) related to the enhanced bulk damage resistance was investigated by using transmittance measurements. Pulsed laser beams at wavelengths of 532 and 266 nm were irradiated to CLBO crystals having several bulk damage resistances while the pulsed laser energy is varied from low enough to be negligible nonlinear absorption up to just below the laser-induced damage threshold. At a wavelength of 532 nm, the nonlinear absorption did not occur even at the laser fluence just below the damage threshold. In contrast, two-photon absorption depending on the bulk damage resistance was clearly observed at a wavelength of 266 nm. A high-quality CLBO having a high-damage resistance shows a 2 times lower two-photon absorption coefficient than that of a conventional CLBO.
Synthesis of Pt-Entrapped Titanate Nanotubes
Authors: Nakahira Atsushi , Kubo Takashi , Yamasaki Yuki , Suzuki Toshiyuki , Ikuhara Yuichi
Published: July 2005

In this study, Pt-entrapped titanate nanotubes with approximately 10 to 15 nm in outer diameter and 5 nm in inner diameter and several hundreds in length were synthesized by a hydrothermal treatment of titanium oxide as a source material and a subsequent heat-treatment of the mixture of these titanate nanotube and a Pt salt. According to TEM observations, Pt nanocrystals with a few nm in diameter and 5 to 10 nm in length were contained in titanate nanotubes. These Pt nanocrystal-entrapped titanate nanotubes had the high photocatalytic properties, which are also expected to be a useful material for nanotechnology applications.
Current-Induced Plastic Deformation of Double-Walled Carbon Nanotubes
Authors: Nakayama Yoshikazu , Nagataki Atsuko , Suekane Osamu , Cai Xiaoyu , Akita Seiji
Published: July 2005

We induced a permanent plastic deformation in an originally straight double-walled nanotube by applying current to an individual nanotube that had been bent elastically under mechanical duress. This method is controllable and allows nanotubes' application as building blocks in nanostructures. Inserting pentagon–heptagon pairs into a nanotube created bending angles of 20–30°. The onset of plastic deformation, as measured using the current circumference-density, is less than 1/20 that of the sublimation. The onset decreases with increasing nanotube diameter. This process is performed using a transmission electron microscope: electron beam energy is not essential for the process but decreases the onset.
Reduced Leakage Current in BiFeO3 Thin Films on Si Substrates Formed by a Chemical Solution Method
Authors: Singh Sushil K. , Ishiwara Hiroshi
Published: July 2005

BiFeO3 (BFO) thin films were formed by depositing sol–gel solutions on Pt/Ti/SiO2/Si<100> substrates. Five minute annealing in a nitrogen atmosphere at 550°C was sufficient to obtain crystalline BFO films. The leakage current density in BFO films was found to decrease markedly after optimizing the process conditions of stoichiometric BFO chemical solution. The leakage current density in the range of 10-8 A/cm2 was observed for the first time in BFO thin films at room temperature (RT). This range is four orders of magnitude lower than the reported typical value at RT in pure BFO films. Due to the improved leakage current, we could measure nonsaturated and saturated P–E (polarization vs electric field) hysteresis loops at respective RT and 80 K in the BFO films. The saturated remanent polarization at 80 K was 90 µC/cm2.
Formation of Nanoscale Diamond Particles without Substrate Heating by Cathodic Arc Deposition
Authors: Aoki Katsunori , Suzuki Keisuke , Ishii Kazuhisa , Takanashi Kumiko , Komukai Takuji , Oura Kenjiro , Hirao Takashi
Published: July 2005

A carbon film grown at room temperature using a cathodic arc process in ambient gases such as N2 and He was investigated by Raman spectroscopy and scanning electron microscopy (SEM). Diamond particles were found to be formed at a constant total pressure of 10-2 Pa, while graphite-like carbon was grown at a lower pressure of around 10-3 Pa in the lower P
(He)/P
(Total) region and tetrahedral amorphous carbon was grown at a higher pressure such as 10-1 Pa. The diamond particles were randomly distributed in the film and had sizes in the range of 50–200 nm.
Temperature Dependence of Tunnel Magnetoresistance in Co–Mn–Al/Al–Oxide/Co–Fe Junctions
Authors: Oogane Mikihiko , Nakata Jun , Kubota Hitoshi , Ando Yasuo , Sakuma Akimasa , Miyazaki Terunobu
Published: July 2005

We investigated the temperature dependence of the tunnel magnetoresistance (TMR) effect in Co–Mn–Al/Al–oxide/Co–Fe tunnel junctions. The junction prepared without exposure to air during deposition showed very large TMR ratios of 65% at 10 K and 40% at room temperature. In contrast, the junction prepared with air exposure before and after Al–oxide layer fabrication showed a maximum TMR ratio of only 40% at a low temperature. Temperature dependences of tunnel conductance of these junctions were analyzed using a simple model that incorporates two contributions: elastic tunneling with decreasing spin polarization as temperature increases and spin-independent hopping tunneling through trap states in Al–oxide tunnel barriers. Results of analyses indicated that air exposure drastically reduced spin polarization and Curie temperature. It also created an inferior insulating layer at the Co–Mn–Al/Al–oxide interface.
Floating Zone Growth of Si Bicrystals Using Seed Crystals with Artificially Designed Grain Boundary Configuration
Authors: Usami Noritaka , Kitamura Masayuki , Sugawara Takamasa , Kutsukake Kentaro , Ohdaira Keisuke , Nose Yoshitaro , Fujiwara Kozo , Shishido Toetsu , Nakajima Kazuo
Published: July 2005

We attempted to grow Si bicrystals with a controlled grain boundary configuration using a pair of single-crystal seeds, which was purposely designed to have a specified character. The floating zone technique under an ultrahigh-vacuum environment was exploited to grow bicrystals and the growth rate was found to be important to control the grain boundary configuration. The grown bicrystals are useful for the fundamental study of the role of grain boundaries, which might control the overall properties of multicrystals. As one of the examples, a series of Si bicrystals, which were grown using seed crystals with a specified misorientation from Σ3, was processed in solar cells, and the short-circuit current density was found to be strongly affected by the misorientation given to the seed.
Self-Aligned-Gate Metal/Ferroelectric/Insulator/Semiconductor Field-Effect Transistors with Long Memory Retention
Authors: Takahashi Mitsue , Sakai Shigeki
Published: July 2005

Self-aligned-gate Pt/SrBi2Ta2O9/HfAlO/Si metal/ferroelectric/insulator/semiconductor (MFIS) field-effect transistors (FETs) were fabricated. Drain current (I
d) versus gate voltage curves of the MFIS FETs showed almost the same steepness as that of a non-self-aligned-gate Pt/HfAlO/Si metal/insulator/semiconductor FET. Long retention times with large on- and off-state I
d ratios were obtained for the MFIS FETs. The retention times more than 33 days with an on- and off-state I
d ratio over 105 were demonstrated for the self-aligned-gate MFIS FET with a 2-µm-long and 80-µm-wide gate. This device showed the longest memory retention among all of the ferroelectric-gate FETs reported ever before.
Tilted Liquid Crystal Alignment on Asymmetrically Grooved Porous Alumina Film
Authors: Maeda Tsuyoshi , Hiroshima Kohki
Published: July 2005

This paper reports the achievement of tilted liquid crystal (LC) alignment on an anodic porous alumina (APA) film using microgrooves with asymmetric shapes and dozens of minute pores. The microgrooves with asymmetric shapes were formed by a rubbing technique. The minute pores were then produced by anodization. The LC pretilt angle was controlled by the shapes of the microgrooves and pores. The LC director was orientated in the same inclining direction as that of a rubbed polyimide (PI) film. The pretilt angle was in the range of 20 to 90°. This tilted LC alignment remains very stable against external forces such as thermal shock and intense light.
Posttreatment-Dependent Current Degradation and Role of Tube Length on Morphology of Printed Carbon Nanotube Field Emitters
Authors: Kim Yong Churl , Sohn Kwon Hee , Cho Young Mok , Yoo Eun Ho
Published: July 2005

Field-emission current was degraded very fast down to less than 20% from its initial maximum in a few min when the printed carbon nanotubes were activated with adhesive tape. Conversely, initial increasing behavior and negligible degradation over 10 h were observed from samples treated with a soft-rubber roller. The severe destruction of nanotube skeletons and residual contaminants on tube walls induced by taping were interpreted to lead to the fast degradation of current. In addition, we show that the vertical alignment of nanotubes is strongly affected by tube length. Although 2–5-µm-long tubes were well aligned through field emission, nanotubes with a length of 100 µm or larger showed a seriously entangled morphology leading to nonuniform emission images.
Polymer Device of Poly(3-hexylthiophene) with a Cathode Fabricated from Silver Nanoparticles by Wet Processing
Authors: Kajii Hirotake , Maki Hideki , Kin Zenken , Morimune Taichiro , Ohmori Yutaka
Published: July 2005

The fabrication and characteristics of a polymer device of poly(3-hexylthiophene) (PAT6) with a cathode fabricated from silver (Ag) nanoparticles were investigated. As the formation temperature is 210°C, the cathode electrode can be formed by wet processing on the organic layer with an amorphous carbon nitride buffer layer and a bank to prevent Ag nanoparticles from penetrating into the organic layer. The PAT6 device with a cathode fabricated from Ag nanoparticles shows a photo-response and a red emission in the reverse and forward bias regions, respectively. We demonstrated the possibility of a polymer photodiode and an organic light-emitting diode with a cathode utilizing Ag nanoparticles.
Strongly Enhanced Sensitivity of Piezoresistive Cantilevers by Utilizing the Superconducting Proximity Effect
Authors: Okamoto Hajime , Akazaki Tatsushi , Ueki Mineo , Yamaguchi Hiroshi
Published: July 2005

We fabricated a novel piezoresistive cantilever that integrates a superconductor–semiconductor–superconductor (S–Sm–S) junction. The cantilever was processed from an InAs/AlGaSb heterostructure and a submicron-size niobium gap was patterned to form a Nb–InAs–Nb junction, at which the deflection of the cantilever can be detected as resistance change, i.e., piezoresistance. The resulting piezoresistance at ∼2 K strongly depends on the bias current, and we confirmed that the piezoresistance is enhanced by two orders of magnitude at the critical current, where transition between superconducting state and normal state occurs in the S–Sm–S junction. This indicates that S–Sm–S junctions can be applied for highly sensitive displacement and force sensors.
Blue Light Emission from Ultrafine Nanosized Powder of Silicon Produced by Intense Pulsed Ion-Beam Evaporation
Authors: Yatsui Kiyoshi , Gunji Michiharu , Yang Sung-Chae , Suematsu Hisayuki , Jiang Weihua , Yatsui Takashi , Ohtsu Motoichi
Published: July 2005

Blue light emission has been observed from ultrafine nanosized powder of silicon, which was synthesized by rapid cooling of high-density ablation plasma produced by intense pulsed light-ion beam interaction with a silicon target, called pulsed ion-beam evaporation. The emission appears from the powder without heat treatment after being synthesized. Furthermore, the emission is found to be very stable; neither red- nor blue-shift is observed. In fact, the spectrum from the powder four months after the synthesis is the same as those from as-synthesized powder. The rapid heat cooling inherent to ion-beam evaporation seems to be essential for emission.
ETA receptor blockade prevents renal dysfunction in salt-sensitive hypertension induced by sensory denervation
Authors: Wang Youping , Chen Alex F. , Wang Donna H.
Published: July 2005

To test the hypothesis that activation of the endothelin type A (ETA) receptor contributes to decreased renal excretory function and increased blood pressure in sensory nerve-degenerated rats fed a high-salt diet, neonatal Wistar rats were given vehicle or capsaicin (CAP, 50 mg/kg sc) on the first and second day of life. After being weaned, vehicle or CAP-treated rats were fed a normal (NS, 0.5%) or a high- (HS, 4%) sodium diet for 2 wk with or without ABT-627 (5 mg·kg−1·day−1, a selective ETA receptor antagonist). Systolic blood pressure increased in CAP-treated rats fed a HS diet (CAP-HS) compared with vehicle-treated rats fed a HS diet (CON-HS, 145 ± 7 vs. 89 ± 5 mmHg, P < 0.05). Creatinine clearance and fractional sodium excretion (FENa) decreased in CAP-HS rats compared with CON-HS rats (creatinine clearance, 0.54 ± 0.05 vs. 0.81 ± 0.09 ml·min−1·100 g body wt−1; FENa, 8.68 ± 0.99 vs. 12.53 ± 1.47%, respectively; P < 0.05). Water and sodium balance increased in CAP-HS rats compared with CON-HS (water balance, 20.2 ± 1.5 vs. 15.5 ± 1.9 ml/day; sodium balance, 11.9 ± 3.1 vs. 2.4 ± 0.3 meq/day, respectively; P < 0.05). The endothelin (ET)-1 levels in plasma and isolated glomeruli increased by about twofold in CAP-HS rats compared with CON-HS rats ( P < 0.05). ABT-627 prevented the decrease in creatinine clearance and FENa, the increase in water and sodium balance, and the increase in blood pressure in CAP-HS rats ( P < 0.05). Therefore, the blockade of the ETA receptor ameliorates the impairment of renal excretory function and prevents the elevation in blood pressure in salt-sensitive hypertension induced by degeneration of sensory nerves, indicating that the activation of the ETA receptor impairs renal function and contributes to the development of a salt-induced increase in blood pressure in this model.
NHE3 in an ancestral vertebrate: primary sequence, distribution, localization, and function in gills
Authors: Choe Keith P. , Kato Akira , Hirose Shigehisa , Plata Consuelo , Sindić Aleksandra , Romero Michael F. , Claiborne J. B. , Evans David H.
Published: July 2005

In mammals, the Na+/H+exchanger 3 (NHE3) is expressed with Na+/K+-ATPase in renal proximal tubules, where it secretes H+and absorbs Na+to maintain blood pH and volume. In elasmobranchs (sharks, skates, and stingrays), the gills are the dominant site of pH and osmoregulation. This study was conducted to determine whether epithelial NHE homologs exist in elasmobranchs and, if so, to localize their expression in gills and determine whether their expression is altered by environmental salinity or hypercapnia. Degenerate primers and RT-PCR were used to deduce partial sequences of mammalian NHE2 and NHE3 homologs from the gills of the euryhaline Atlantic stingray ( Dasyatis sabina). Real-time PCR was then used to demonstrate that mRNA expression of the NHE3 homolog increased when stingrays were transferred to low salinities but not during hypercapnia. Expression of the NHE2 homolog did not change with either treatment. Rapid amplification of cDNA was then used to deduce the complete sequence of a putative NHE3. The 2,744-base pair cDNA includes a coding region for a 2,511-amino acid protein that is 70% identical to human NHE3 (SLC9A3). Antisera generated against the carboxyl tail of the putative stingray NHE3 labeled the apical membranes of Na+/K+-ATPase-rich epithelial cells, and acclimation to freshwater caused a redistribution of labeling in the gills. This study provides the first NHE3 cloned from an elasmobranch and is the first to demonstrate an increase in gill NHE3 expression during acclimation to low salinities, suggesting that NHE3 can absorb Na+from ion-poor environments.
Hemodynamic and autonomic changes induced by Ironman: prediction of competition time by blood pressure variability
Authors: Gratze Gerfried , Rudnicki Richard , Urban Wolfgang , Mayer Harald , Schlögl Alois , Skrabal Falko
Published: July 2005

We hypothesized that the extreme endurance exercise of an Ironman competition would lead to long-standing hemodynamic and autonomic changes. We investigated also the possibility of predicting competition performance from baseline hemodynamic and autonomic parameters. We have investigated 27 male athletes before competition, 1 h after, and then for the following week after the competition. The Task Force monitor was used to measure beat-to-beat hemodynamic and autonomic parameters during supine rest and active standing. Heart rate ( P < 0.001) was increased, and stroke index ( P = 0.011), systolic blood pressure ( P = 0.004), diastolic blood pressure ( P < 0.001), total peripheral resistance index ( P < 0.001), and baroreceptor reflex sensitivity ( P < 0.001) were decreased after the competition. The 0.05- to 0.17-Hz band of heart rate and blood pressure variability was increased ( P < 0.001 and P < 0.001, respectively), the 0.17- to 0.40-Hz band of heart rate interval variability was decreased after the competition ( P < 0.001). All parameters returned to baseline values 3 days after the competition. After the competition, the autonomic response to orthostasis was significantly impaired. The 0.05- to 0.17-Hz band of diastolic blood pressure variability before competition and weekly net exercise training, but not the other hemodynamic and autonomic parameters, were related to competition time in multivariate regression analysis (multiple r = 0.70, P < 0.001). The marked hemodynamic and autonomic changes after an ultraendurance race, which are compatible with myocardial depression in the face of sympathetic activation and reduction of afterload, return to baseline after only 1–3 days. Because the 0.05- to 0.17-Hz band of diastolic blood pressure variability contributes to the prediction of competition time, the analysis of blood pressure variability in the frequency domain deserves further study for the prediction of endurance capacity.
Shear Stress Induces Endothelial Differentiation From a Murine Embryonic Mesenchymal Progenitor Cell Line
Authors: Wang Hao , Riha Gordon M. , Yan Shaoyu , Li Min , Chai Hong , Yang Hui , Yao Qizhi , Chen Changyi
Published: July 2005

Objective—

Recent studies have illustrated that mesenchymal stem cells possess the potential to differentiate along an endothelial lineage, but the effect of shear on mesenchymal differentiation is unknown. Thus, we developed an in vitro shear stress system to examine the relationship between shear stress and the endothelial differentiation of a murine embryonic mesenchymal progenitor cell line, C3H/10T1/2.

Methods and Results—

The parallel plate system of fluid shear stress was used. Shear stress significantly induced expression of mature endothelial cell–specific markers in CH3H/10T1/2 cells such as CD31, von Willebrand factor, and vascular endothelial–cadherin at both the mRNA and protein levels with real-time polymerase chain reaction and immunofluorescence analyses, respectively. In addition, shear-induced augmentation of functional markers of the mature endothelial phenotype such as uptake of acetylated low-density lipoproteins and formation of capillary-like structures on Matrigel. Furthermore, shear stress significantly upregulated angiogenic growth factors while downregulating growth factors associated with smooth muscle cell differentiation.

Conclusions—

This study demonstrates, for the fist time, endothelial differentiation in a mesenchymal progenitor CH3H/10T1/2 cell line resulting from shear exposure. Thus, this analysis may serve as a basis for further understanding the effect of shear on mesenchymal and vascular cell differentiation.
Custom Design of the Cardiac Microenvironment With Biomaterials
Authors: Davis Michael E. , Hsieh Patrick C.H. , Grodzinsky Alan J. , Lee Richard T.
Published: July 2005

Many strategies for repairing injured myocardium are under active investigation, with some early encouraging results. These strategies include cell therapies, despite little evidence of long-term survival of exogenous cells, and gene or protein therapies, often with incomplete control of locally-delivered dose of the factor. We propose that, ultimately, successful repair and regeneration strategies will require quantitative control of the myocardial microenvironment. This precision control can be engineered through designed biomaterials that provide quantitative adhesion, growth, or migration signals. Quantitative timed release of factors can be regulated by chemical design to direct cellular differentiation pathways such as angiogenesis and vascular maturation. Smart biomaterials respond to the local environment, such as protease activity or mechanical forces, with controlled release or activation. Most of these new biomaterials provide much greater flexibility for regenerating tissues ex vivo, but emerging technologies like self-assembling nanofibers can now establish intramyocardial cellular microenvironments by injection. This may allow percutaneous cardiac regeneration and repair approaches, or injectable-tissue engineering. Finally, materials can be made to multifunction by providing sequential signals with custom design of differential release kinetics for individual factors. Thus, new rationally-designed biomaterials no longer simply coexist with tissues, but can provide precision bioactive control of the microenvironment that may be required for cardiac regeneration and repair.
How Inter-Christian Approaches to Paul's Rhetoric Can Perpetuate Negative Valuations of Jewishness—Although Proposing to Avoid that Outcome
Authors: Nanos Mark
Published: July 2005

An unrecognized problem arises in recent inter-mural Christian constructions of the settings for interpreting Paul's polemic, wherein negative valuations of Jewishness persist in the discourse, regardless of stated intentions to avoid that outcome. This approach has masked the perpetuation of Christianness versus Jewishness, since moving it inside of Christianity does not eliminate the fact that what is negatively valued for non-Pauline (read "non-Gentile") Christianity is the degree to which it remains Jewish (regards Jewish identity and behavior as valuable expressions of faith). The discourse has changed a lot, but not to the degree that would match the stated intentions, and for the Jewish–Christian relations critic, the explicit although often subtle reminders of this persistent prejudice against Jewishness in writings about Paul is painful to continue to discover in (and between) the lines of many contemporary works.
Does Paul Need to Be Saved?
Authors: Setzer Claudia
Published: July 2005

While many liberal Jews have endorsed Jesus as one of their own for at least a century, Paul has often borne the blame for injecting anti-Judaism into early Christianity. The work of these scholars helps overturn these judgments against Paul. Several emphases of their work help us to better appreciate Paul as a pedagogue of multiple identities. 1) Being "in Christ" and being part of Israel are compatible, not contradictory identities for Paul. 2) Paul believes that Gentiles, by being "in Christ" come under the umbrella of Israel, even without circumcision or conversion. 3) Paul's mission as the teacher to the Gentiles shapes every aspect of his rhetoric and message. 4) Paul is animated by the question of Gentile inclusion in God's people, not the existential guilt of the individual. This article also poses four questions as we pursue this approach to Paul. 1) Why does Paul, the robust Jew who continues to believe in Israel's election, so virulently oppose Gentile circumcision or conversion, which was part of the Judaism of his time? 2) What is the role of the cross, which does not spring from the language and myths of Israel, in Paul's thought? 3) Does Paul think he is doing anything new, particularly since he uses the language of novelty? 4) How much does Paul need to be "saved," i.e. made to conform to our contemporary standards, for us to appreciate him as part of our experience and traditions?
The Impact of New Perspectives on Judaism and Improved Jewish–christian Relations on the Study of Paul
Authors: Gaston Lloyd
Published: July 2005

I urge reversing order in the theme for our session to recognizing the major impact Jewish–Christian relations has had on recent Pauline studies. From a Christian perspective, more important than 'the New Perspective on Paul' has been 'the new perspective on early Judaism.' I will try to test these theses in reference to the work of two important contemporary Pauline scholars, Ed Sanders and Mark Nanos.
The Figure of Apion in Josephus' Contra Apionem
Authors: Jones Kenneth
Published: July 2005

A comparison of Josephus' portrait of Apion with other ancient testimonia shows that the Jewish historian, in his effort to discredit the grammarian, focused on the same failing of character that other ancient authors had found. Josephus also aimed a deceptive attack at Apion's ethnicity wherein he blurs the line between the Alexandrian's Greek cultural identity and his Egyptian origin. Josephus took pains to construct an ideal opponent, one with whom the reader of Josephus' treatise—be he Jew, Greek, or Roman—would not sympathize. An analysis of Apion's "case" against the Jews shows that Josephus himself culled various Jewish items from Apion's Aegyptiaca and, after distorting the original intention of the excerpts, cobbled them together to form an easily refuted indictment of Jewish history and practices. An appendix examines the evidence for a supposed attributed to Apion.
Clinical Comparison of the Tutoplast Allograft and Autologous Patellar Tendon (Bone-Patellar Tendon-Bone) for the Reconstruction of the Anterior Cruciate Ligament
Authors: Gorschewsky Ottmar , Klakow Andreas , Riechert Kathrin , Pitzl Martin , Becker Roland
Published: July 2005

Background

The use of an allograft as a suitable transplant is still open to debate, in terms of donor morbidity, implantation reaction, and long-term results, as well as the risk of disease transmission.

Hypothesis

The clinical results 2 and 6 years after implantation of a bone-patellar tendon-bone allograft (Tutoplast) and bone-patellar tendon-bone autograft show no significant difference in relation to stability, function, and rate of rupture.

Study Design

Cohort study; Level of evidence, 2.

Method

Between 1995 and 1998, 268 patients with anterior cruciate ligament ruptures were surgically treated: 132 patients received a bone-patellar tendon-bone allograft implantation and 136 patients a bone-patellar tendon-bone autograft. The results were evaluated using the International Knee Documentation Committee, Noyes, and Lysholm scores.

Results

There were 201 patients assessable after 2 years and 186 patients after 6 years. Ruptures of the implants in the allo-graft group occurred in 20 patients (20.6%) within 2 years and in 38 patients (44.7%) after 6 years. In the autograft group, transplants ruptured in 5 patients (4.8%) after 2 years and in 6 patients (5.9%) after 6 years.

Conclusion

Based on the data, it would appear that the regular use of bone-patellar tendon-bone allografts, particularly for physically active patients, is unsuitable.
Ankle Joint Proprioception and Postural Control in Basketball Players with Bilateral Ankle Sprains
Authors: Fu Amy S. N. , Hui-Chan Christina W. Y.
Published: July 2005

Background

Deficiencies in ankle proprioception and standing balance in basketball players with multiple ankle sprains have been reported in separate studies. However, the question of how ankle proprioceptive inputs and postural control in stance are related is still unclear.

Hypothesis

Ankle repositioning errors and the amount of postural sway in stance are increased in basketball players with multiple ankle sprains.

Study Design

Controlled laboratory study.

Methods

Twenty healthy male basketball players and 19 male basketball players who had suffered bilateral ankle sprains within the past 2 years were examined. Both groups were similar in age. Passive ankle joint repositioning errors at 5° of plantar flexion were used to test for ankle joint proprioception. The Sensory Organization Test was applied with dynamic posturography to assess postural sway angle under 6 sensory conditions.

Results

A significant increase in ankle repositioning errors was demonstrated in basketball players with bilateral ankle sprains (P < .05). The mean errors in the right and left ankles were increased from 1.0° (standard deviation, 0.4°) and 0.8° (standard deviation, 0.2°), respectively, in the healthy players to 1.4° (standard deviation, 0.7°) and 1.1° (standard deviation, 0.5°) in the injured group. A significant increase in the amount of postural sway in the injured subjects was also found in conditions 1, 2, and 5 of the Sensory Organization Test (P < .05). Furthermore, there were positive associations between averaged errors in repositioning both ankles and postural sway angles in conditions 1, 2, and 3 of the Sensory Organization Test (r = 0.39-0.54, P < .05).

Conclusions

Ankle repositioning errors and postural sway in stance increased in basketball players with multiple ankle sprains. A positive relationship was found between these 2 variables.

Clinical Relevance

Such findings highlight the need for the rehabilitation of patients with multiple ankle sprains to include proprioceptive and balance training.
Endoscopic Reconstruction of the Anterior Cruciate Ligament using Bone-Patellar Tendon-Bone Grafts Fixed with Bioabsorbable or Metal Interference Screws
Authors: Drogset Jon Olav , Grøntvedt Torbjørn , Tegnander Agnar
Published: July 2005

Background

During the past decade, bioabsorbable interference screws have become increasingly popular in endoscopic reconstructions of the anterior cruciate ligament. With these screws, there is no need for a second operation for removal and no complicating factor if later revision surgery is necessary. Several pullout studies have found similar results between metal and bioabsorbable interference screws; however, few studies have investigated the clinical outcome.

Hypothesis

There is no difference in the clinical outcome of bioabsorbable interference screws compared with metal screws.

Study Design

Randomized controlled clinical trial; Level of evidence, 1.

Methods

Forty-one patients were randomized for the use of either metal interference screws (20 patients) or bioabsorbable poly-L-lactic acid screws (21 patients). The patients were followed with clinical examinations at 6, 12, and 24 weeks and at 1 and 2 years postoperatively.

Results

Subjective knee function was better in the patients in the metal screw group; they had less pain at rest, a higher Tegner score, a higher Lysholm score, and better subjective knee function at 2 years compared to the bioabsorbable screw group. However, there was no difference in stability between the groups.

Conclusion and Clinical Relevance

Because of the inferior results in the bioabsorbable screw group in our study, and until larger studies show otherwise, we do not find the advantages of using bioabsorbable screws sufficient to warrant the routine use of poly-L-lactic acid screws in anterior cruciate ligament reconstructions.
The Kim Test
Authors: Kim Seung-Ho , Park Jun-Sic , Jeong Woong-Kyo , Shin Seong-Kee
Published: July 2005

Background

Detection of a posteroinferior labral lesion by physical examination is often difficult.

Purpose

To introduce a novel diagnostic test for detecting a posteroinferior labral lesion of the shoulder.

Hypothesis

The Kim test can detect a posteroinferior labral lesion of the shoulder.

Study Design

Cohort study (diagnosis); Level of evidence, 1.

Methods

In 172 painful shoulders, the Kim test was compared with the jerk test and was verified by arthroscopic examination. A sudden onset of posterior shoulder pain and click with or without clunk indicated a positive test result.

Results

Thirty-three shoulders had a positive Kim test result, in which 24 had a posteroinferior labral lesion and 9 had a normal posteroinferior labrum. Of 139 shoulders with a negative Kim test result, 6 had a posteroinferior labral tear and 133 had a normal posteroinferior labrum. The sensitivity of the Kim test was 80%, specificity was 94%, positive predictive value was 0.73, and negative predictive value was 0.96. The interexaminer reliability between 2 examiners was 0.91. The accuracy of the jerk test in detecting a posteroinferior labral lesion was the following: sensitivity, 73%; specificity, 98%; positive predictive value, 0.88; and negative predictive value, 0.95. The location of the posterior labral lesion was predominantly posterior in 19 shoulders and predominantly inferior in 11 shoulders. The Kim test was more sensitive in detecting a predominantly inferior labral lesion, whereas the jerk test was more sensitive in detecting a predominantly posterior labral lesion. The sensitivity in detecting a posteroinferior labral lesion increased to 97% when the 2 tests were combined.

Conclusion

The Kim test is a reliable diagnostic test for detection of a posteroinferior labral lesion.