bluuebunny/crossref_metadata_2025 huggingface dataset:
Fe-based bulk glassy alloy composite containing in situ formed α-(Fe,Co) and (Fe,Co)23B6 microcrystalline grains
Authors: Shen Baolong , Men He , Inoue Akihisa
Published: September 2006

We report on an {[(Fe0.5Co0.5)0.75B0.2Si0.05]96Nb4}99.75Cu0.25 bulk glassy alloy (BGA) composite containing in situ formed α-(Fe,Co) and fcc-(Fe,Co)23B6 microcrystalline grains produced by copper mold casting. By adding 0.25 at. % Cu exhibiting positive mixing enthalpy with Fe, α-(Fe,Co) and fcc-(Fe,Co)23B6 phases with a grain size of 3μm precipitated from the melt during casting, yielding an in situ Fe-based BGA composite. The resulting Fe-based BGA composite shows not only a superhigh fracture strength of 4050MPa but also distinguished yielding combined with an enhanced plastic strain of 0.6% to failure in a compression relative to the [(Fe0.5Co0.5)0.75B0.2Si0.05]96Nb4 single-phase BGA.
Subnanosecond diode-pumped passively Q-switched Nd:GdVO4 laser with peak power >1MW
Authors: Agnesi Antonio , Pirzio Federico , Reali Giancarlo , Piccinno Giuliano
Published: September 2006

The authors report on a passively Q-switched diode-pumped Nd:GdVO4 miniature laser generating 0.5mJ pulses at 1063nm, with 420ps time duration and 1.2MW peak power, at a repetition rate up to 200Hz and with a nearly diffraction-limited beam quality (M2≈1.1).
Anisotropy measurements in metal alloys using a laser/electromagnetic acoustic transducer array system
Authors: Dutton B. , Dewhurst R. J.
Published: September 2006

Rayleigh waves have been used to measure anisotropy in metal alloys using a transient Rayleigh pulse and an eight-element electromagnetic acoustic transducer array. The array spacing determined sensor separation, so that velocity measurements were made independent of the source-to-detector distance. Elimination of this distance, which would normally lead to systematic errors, has resulted in a measurement system capable of measuring velocities in metal to an uncertainty of 0.1%. As an example, variations in the Rayleigh velocity have characterized the anisotropy in rolled bars of aluminum.
Optical transmission larger than 1 (T>1) through ZnS–SiO2∕AgOx∕ZnS–SiO2 sandwiched thin films
Authors: Wei Jingsong , Xiao Mufei
Published: September 2006

Optical transmission through flat media should be smaller than 1. However, we have observed optical transmission up to T=1.18. The samples were ZnS–SiO2∕AgOx∕ZnS–SiO2 sandwiched thin films on glass substrate. The supertransmission could only be observed in the near field. We attribute the supertransmission to the lateral propagation relayed by the laser activated and decomposed Ag nanoparticles.
Free-space quantum key distribution with entangled photons
Authors: Marcikic Ivan , Lamas-Linares Antía , Kurtsiefer Christian
Published: September 2006

The authors report on a complete experimental implementation of a quantum key distribution protocol through a free-space link using polarization-entangled photon pairs from a compact parametric downconversion source. Over 10h of uninterrupted communication between sites 1.5km apart, they observe average key generation rates of 630∕s after error correction and privacy amplification. Their scheme requires no specific hardware channel for synchronization apart from a classical wireless link, and no explicit random number generator.
Integrated optics Bragg filters made by ion exchange and wafer bonding
Authors: Gardillou F. , Bastard L. , Broquin J.-E.
Published: September 2006

A polarization-insensitive Bragg filter has been realized on a glass substrate thanks to the epoxy-free wafer bonding technique. This device is based on the combined embedding of a corrugated grating and a surface ion-exchanged waveguide, both realized on a silicate glass. With this configuration, the grating patterns are also protected from external degradation of the environment.
Uniaxial tensile plastic deformation of a bulk nanocrystalline alloy studied by a high-energy x-ray diffraction technique
Authors: Fan G. J. , Fu L. F. , Wang Y. D. , Ren Y. , Choo H. , Liaw P. K. , Wang G. Y. , Browning N. D.
Published: September 2006

By employing a high-energy x-ray diffraction technique, the authors report that uniaxial tensile plastic deformation induced the grain growth and texture development in a bulk nanocrystalline Ni–Fe alloy. The effects become more pronounced with increasing the plastic strain (closer to the fracture surface). The texture development accompanying the grain rotation indicates that dislocation motion contributed to the observed plasticity in the nanocrystalline Ni–Fe alloy. The quantitative experimental data suggest that the dislocation storage was absent in the uniformly deforming region; whereas the dislocation storage was present in the necking region, where the grain growth was substantial.
Effects of atomic hydrogen and active carbon species in 1mm vertically aligned single-walled carbon nanotube growth
Authors: Xu Ya-Qiong , Flor Erica , Schmidt Howard , Smalley Richard E. , Hauge Robert H.
Published: September 2006

A hot filament chemical vapor deposition (HFCVD) method has been used to investigate the effects of atomic hydrogen and active carbon species on the growth of 1mm vertically aligned single-walled carbon nanotubes (VA-SWNTs). Isotopic shifts of the tangential phonon mode of SWNTs indicate that SWNT growth occurs primarily via reactions of acetylene and ethylene. The authors find that the presence of atomic hydrogen and active carbon species such as ethylene and acetylene appears to be essential for both nucleation and growth of VA-SWNTs in this HFCVD.
Low-threshold and continuously tunable Yb:Gd2SiO5 laser
Authors: Li Wenxue , Hao Qiang , Zhai Hui , Zeng Heping , Lu Wei , Zhao Guangjun , Yan Chengfeng , Su Liangbi , Xu Jun
Published: September 2006

Yb : Gd 2 Si O 5 (Yb:GSO) exhibits a large fundamental manifold splitting. Its long-wavelength emission band around 1088nm, which has the largest emission cross section, encounters the lowest reabsorption losses caused by thermal population of the terminal laser level. As a result, low-threshold and tunable continuous-wave Yb:GSO lasers were demonstrated. A slope efficiency up to 86% and a pumping threshold as low as 127mW were achieved for a continuous-wave Yb:GSO laser at 1092.5nm under the pump of a high-brightness laser diode. A continuous tunability between 1000 and 1120nm was realized with an SF14 prism as the intracavity tuning element.
Enhanced photorefractive properties of LiNbO3:Fe crystals by HfO2 codoping
Authors: Li Shuqi , Liu Shiguo , Kong Yongfa , Xu Jingjun , Zhang Guangyin
Published: September 2006

Photorefractive properties of congruent lithium niobate crystals codoped with HfO2 and Fe2O3 were investigated and it was found that Fe ions are still located at Li sites as photorefractive centers when the doping concentration of HfO2 goes above the threshold value. As a result, their photorefractive response speed and sensitivity are significantly enhanced. Meanwhile, the high saturation diffraction efficiency is still maintained. Experimental results definitely show that Hf is now the most effective doping element for LiNbO3:Fe crystal to improve its photorefractive properties.
Density control on self-assembling of Ge islands using carbon-alloyed strained SiGe layers
Authors: Bernardi A. , Alonso M. I. , Goñi A. R. , Ossó J. O. , Garriga M.
Published: September 2006

The authors show that by deposition of 0.1 ML of carbon prior to the self-assembled growth of Ge quantum dots on a strained Si1−xGex buffer layer a striking decrease in dot density by two orders of magnitude from about 1011to109cm−2 occurs when the Ge content of the buffer layer increases from 0% to 64%. Their results give experimental evidence for a kinetically limited growth mechanism in which Ge adatom mobility is determined by chemical interactions among C, Si, and Ge. Thus, by adjusting the Ge content of the SiGe buffer layer onto which a carbon submonolayer is deposited they are able to fine tune the density of the carbon-induced Ge quantum dots.
New method of high-precision thermometry
Authors: Poulsen Peter , Ault Stanley K.
Published: September 2006

Measurements of temperature using infrared radiation have become common in industry. They are used in process control for materials ranging from steel to glass to silicon, in machinery to monitor component temperature and performance, and to predict component failure. We developed a rapid, noncontact method of accurately measuring the temperature and the spectral emissivity of a surface. Inclusion of the emissivity in the measurement makes it possible to achieve high-precision results. In our method, the power spectrum emitted by a surface is measured first by a multichannel spectrometer; the surface is then illuminated by a full-spectrum light source with a known spectrum, and the sum of the emitted and reflected power from the surface is measured. The data from the two measurements and the governing relations for the radiation and reflection processes are then combined to generate a set of curves that intersects near a solution point, which yields the temperature and the emissivity in the range of wavelengths of one of the channels. The emissivity in the other channels is readily calculated and yields the wavelength-dependent emissivity of the surface. The accuracy of the method for very rapid (submicrosecond) measurements is approximately 1% or less. We named this method the spectrum method because it uses the spectrum of both the emitted and reflected light to make the calculation. The method is more accurate than a grey body calculation because the wavelength-dependent emissivity is an integral part of the calculation of the surface temperature. The accuracy of the temperature and emissivity measurements can be calculated for a system containing five or more channels. We discuss the sources of errors and quantitatively assess their effect. Relative as well as absolute values of the channel emissivities have a significant effect on errors in the emissivity and temperature measurements. This temperature diagnostic has been tested on a tabletop device that allows us to make quick and reproducible measurements.
Dielectric and magnetic enhancements in BiFeO3–PbTiO3 solid solutions with La doping
Authors: Cheng Jinrong , Yu Shengwen , Chen Jianguo , Meng Zhongyan , Cross L. Eric
Published: September 2006

Solid solutions of 0.45(Bi1−xLax)FeO3–0.55PbTiO3 (BLFPTx) for x=0.1, 0.2, and 0.3 were prepared by the mixed oxide method. BLFPTx showed the tetragonal perovskite structure of which the c∕a ratio and Curie temperature decreased with the increase of La content. Significant dielectric and magnetic enhancements were observed for BLFPTx with La doping. The ferroelectric and ferromagnetic hysteresis loops revealed the maximum remanent polarization and magnetization of 28μC∕cm2 and 0.14emu∕g, respectively, for BLFPTx of x=0.3. Results indicated that BLFPTx was of the insulating and switchable multiferroics with both ferroelectric and ferromagnetic properties.
Relativistic Landau damping of longitudinal waves in isotropic pair plasmas
Authors: Laing E. W. , Diver D. A.
Published: September 2006

Landau damping is described in relativistic electron-positron plasmas. Relativistic electron-positron plasma theory contains important new effects when compared with classical plasmas. For example, there are undamped superluminal wave modes arising from both a continuous and discrete mode structure, the former even in the classical limit. We present here a comprehensive analytical treatment of the general case resulting in a compact and useful form for the dispersion relation. The classical pair-plasma case is addressed, for completeness, in an appendix.
High quality epitaxial growth of PbTiO3 by molecular beam epitaxy using H2O2 as the oxygen source
Authors: Gu Xing , Izyumskaya Natalia , Avrutin Vitaly , Morkoç Hadis , Kang Tae Dong , Lee Hosun
Published: September 2006

Single crystalline PbTiO3 films have been epitaxially grown on SrTiO3 (001) substrates by molecular beam epitaxy using H2O2 as the source of active oxygen. The optimum growth conditions have been determined by analyzing a range of growth parameters affecting growth and used to attain single phase and stoichiometric PbTiO3 thin films. In situ reflection high-energy electron diffraction pattern indicated the PbTiO3 films to be grown under a two-dimensional growth mode. The full width at half maximum of the rocking curve of a relatively thin 65nm (001) PbTiO3 film is 6.2arcmin which is indicative of high crystal quality. The band gap of PbTiO3, as determined by ellipsometric measurement, is 3.778eV.
Tristate liquid crystal display with memory and dynamic operating modes
Authors: Jhun Chul Gyu , Chen Chao Ping , Lee Uk Joo , Lee Seong Ryong , Yoon Tae-Hoon , Kim Jae Chang
Published: September 2006

So far, monostable and bistable liquid crystal display (LCD) modes have independently been researched and developed. The authors propose a tristate LCD that can be operated in memory mode as well as dynamic mode. The proposed device has a unique texture of splay, π twist, and bend states with applied voltages and is operated in memory mode or dynamic mode by selective switching of two states among them. They demonstrate switching characteristics of the tristate LCD. This tristate LCD has a long term memory time for memory mode as well as a fast response time for dynamic mode.
Interface states for HfO2∕Si structure observed by x-ray photoelectron spectroscopy measurements under bias
Authors: Maida Osamu , Fukayama Ken-ichi , Takahashi Masao , Kobayashi Hikaru , Kim Young-Bae , Kim Hyun-Chul , Choi Duck-Kyun
Published: September 2006

A 1.0nm silicon nitride (SiN) layer can prevent reaction between HfO2 and Si completely. In this case, the interface state spectra obtained from x-ray photoelectron spectroscopy measurements under bias have two peaks above and below the midgap, attributable to Si dangling bonds interacting weakly with an atom in SiN, indicating a high atomic density of the SiN layer. When a HfO2 layer is deposited on a 1.0nm SiO2 layer, the SiO2 thickness increases to 1.6nm. For this structure, one interface state peak is present near the midgap, attributable to isolated Si dangling bonds, indicating a low atomic density.
Codiffusion of P32 and Co57 in glass-forming Pd43Cu27Ni10P20 alloy and its relation to viscosity
Authors: Bartsch A. , Rätzke K. , Faupel F. , Meyer A.
Published: September 2006

In general, the Stokes-Einstein (SE) equation is well accepted for melts. In the supercooled melt a decoupling of diffusivity and viscosity around the critical temperature Tc of the mode coupling theory is observed. The authors measured simultaneously the P32 and Co57 diffusion in the supercooled melt of the Pd43Cu27Ni10P20 alloy from 573 up to 640K using the radiotracer technique. They found that P and Co have similar diffusivities and compared them to viscosity data using SE equation. This shows that the time scales of Co and P diffusions are decoupled by up to two orders of magnitude from time scales of viscous flow in the supercooled state.
Coeffect of size and stress in Bi3.25La0.75Ti3O12 thin films
Authors: Wu Xiumei , Lu Xiaomei , Kan Yi , Huang Fengzhen , Ma Jun , Zhu Jinsong
Published: September 2006

The coeffect of size and stress on the properties of Bi3.25La0.75Ti3O12 thin films was studied. With the applied stress changing from maximum compression (about −80MPa) to maximum tension (about 80MPa), the remnant polarization increases while the coercive field decreases. The variational extent of the remnant polarization with stress is bigger, while that of the coercive field is smaller in samples with smaller grains. Meanwhile, fatigue properties of films can be improved by stress (especially compression), and the improvement increases with increasing grain size. From these results, the coeffect of size and stress on domain patterns and domain wall movability was deduced.
Optical properties of selectively oxidized vertical cavity laser with depleted optical thyristor structure
Authors: Choi Woon-Kyung , Kim Doo-Gun , Moon Yon-Tae , Choi Young-Wan , Kim Yong-Kwan , Choquette Kent D. , Lee Seok , Woo Deok-Ha
Published: September 2006

The authors show that the optical properties of selectively oxidized vertical cavity lasers with a depleted optical thyristor structure have a low threshold current and high sensitivity to input optical light. The oxidized thyristor laser clearly shows a nonlinear s-shaped current-voltage and lasing characteristics. A switching voltage of 5.24V, a holding voltage of 1.50V, and a very low threshold current of 0.65mA are measured, making these devices attractive for optical processing applications.
Comparison of atmospheric-pressure helium and argon plasmas generated by capacitively coupled radio-frequency discharge
Authors: Li Shou-Zhe , Lim Jin-Pyo , Kang Jung G. , Uhm Han S.
Published: September 2006

In this paper, the electrical discharge characteristics of plasmas generated in coaxial cylindrical electrodes capacitively powered by a radio-frequency power supply at atmospheric pressure are investigated with respect to helium and argon gases. The electrical discharge parameters, voltage (V), current (I), and power (P), are measured for both helium and argon plasmas, and the electron temperatures and electron densities for them are evaluated by means of the equivalent circuit model and the power balance equation. By comparison of the discharge characteristics of the helium and argon plasmas, it is found that the discrepant macroscopic characteristics of helium and argon plasma, viz., current and voltage characteristics and current and power characteristics, are owed to their own intrinsic microscopic parameters of the helium and argon atoms, such as the first excited energy, the ionization energy, the total cross section, and the atom mass. Furthermore, the influences of the additive gas, oxygen gas, on the electrical discharge characteristics are also investigated in the helium and argon plasmas, which are closely related to the electron temperature of plasmas.
Investigation of degradation in beryllium chalcogenide II-VI semiconductors
Authors: Tsai W. C. , Cheng C. L. , Chen T. T. , Chen Y. F. , Huang Y. S. , Firszt F. , Męczyńska H. , Marasek A. , Łęgowski S. , Strzakołwski K.
Published: September 2006

The wurtzite-type Cd1−x−yZnxBeySe crystals grown by the high-pressure Bridgman method were investigated to obtain the suitable beryllium composition for improving the lifetime of II-VI based optoelectronic devices. A method based on the continuous exposure of the electron beam of cathodoluminescence measurement was introduced to probe the aging characteristics of optoelectronic materials. The results show that in order to improve the degradation problem, the incorporation of beryllium content in II-VI compounds should be less than 10%. In addition, the authors demonstrate that cathodoluminescence image is a very powerful tool to reveal the generation of defects of an optoelectronic solid under external perturbation.
Self-sensing neutralizer by means of self-ejected charged particles from ac microhollow cathode discharge
Authors: Lee Tae Il , Noh Joo Hyon , Park Ki Wan , Hwang Hyeon Seok , Baik Hong Koo
Published: September 2006

The authors introduced a concept of self-sensing neutralization system by means of automatically ejected charged particles from alternative current microhollow cathode discharge. When the positive bias was applied to the third electrode, a real current flow was only detected during negative polarity period of voltage applied to the first electrode. On the other hand, in the case of negative bias, there was only the real current during positive polarity period. These results mean that our system shows simultaneously the self-sensing and then neutralizing characteristics in a period.
Detailed-balance power conversion limits of nanocrystal-quantum-dot solar cells in the presence of carrier multiplication
Authors: Klimov Victor I.
Published: September 2006

Semiconductor nanocrystals can respond to absorption of a single photon by producing multiple electron-hole pairs with extremely high efficiencies. This letter analyzes the impact of this carrier-multiplication (CM) phenomenon on power conversion limits of solar cells using detailed-balance considerations that take into account practical values of CM efficiencies measured in experimental studies. For PbSe nanocrystals that exhibit a ca. 3Eg CM threshold (Eg is the energy gap), the calculated maximum detailed-balance efficiency is 36% in the presence of CM versus 31% in the no-CM case. An increase to 42% is possible if the CM threshold is at its theoretical minimum of 2Eg.
Photoluminescence studies of Eu3+ doped Y2O3 nanophosphor prepared by microwave hydrothermal method
Authors: Vadivel Murugan A. , Viswanath Annamraju Kasi , Ravi V. , Kakade Bhalchandra A. , Saaminathan V.
Published: September 2006

In this letter, the authors report the photoluminescence studies of Eu3+ doped Y2O3 nanorods, which have been synthesized by rapid microwave hydrothermal route within 6min. The nanostructured Eu3+ doped Y2O3 is characterized by x-ray diffraction, transmission electron microscopy, and photoluminescence. The emission spectrum shows transitions from the excited 5D0 state to FJ7 (J=0,1,2,3,4) levels of the Eu3+ ion. The most intense peak around 612nm is due to the D05→F27 transition, expected from the Judd-Ofelt selection rules [B. R. Judd, Phys. Rev. 127, 750 (1962); G. S. Ofelt, J. Chem. Phys. 37, 511 (1962)]. Photoluminescence measurements demonstrated that the nanocrystalline Eu3+:Y2O3 phase shows higher photoluminescence intensity.
Confocal operation of a transmission electron microscope with two aberration correctors
Authors: Nellist P. D. , Behan G. , Kirkland A. I. , Hetherington C. J. D.
Published: September 2006

The authors demonstrate that confocal imaging trajectories can be established in a transmission electron microscope fitted with two spherical aberration correctors. An atomic-scale electron beam, focused by aberration-corrected illumination optics, is directly imaged by a second aberration-corrected system. The initial experiment described indicates how aberration-corrected scanning confocal electron microscopy will allow three-dimensional imaging and analysis of materials with atomic lateral resolution and with a depth resolution of a few nanometers. The depth resolution in the confocal mode is shown to be robust to the uncorrected chromatic aberration of the lenses, unlike depth sectioning using a single lens.
Influence of valence electron concentration on elastic properties of RRh3B (R=Y, Zr, and Nb)
Authors: Music Denis , Schneider Jochen M.
Published: September 2006

The authors have systematically studied the correlation between valence electron concentration and elastic properties of RRh3B (space group Pm3¯m, prototype CaTiO3), where R=Y, Zr, and Nb, using ab initio calculations. As the valence electron concentration is increased, the bulk modulus increases by 28%, while C44 decreases by 46%. This can be understood based on the electronic structure. The bulk modulus increases due to band filling, while the C44 decreases since the interaction between covalent-ionic Rh–B and metallic Rh–R layers is characterized by the presence of antibonding states.
Deactivation of phosphatidylinositol 3,4,5-trisphosphate/Akt signaling mediates neutrophil spontaneous death
Authors: Zhu Daocheng , Hattori Hidenori , Jo Hakryul , Jia Yonghui , Subramanian Kulandayan K. , Loison Fabien , You Jian , Le Yi , Honczarenko Marek , Silberstein Leslie , Luo Hongbo R.
Published: September 2006

Neutrophil spontaneous death plays essential roles in neutrophil homeostasis and resolution of inflammation, whereas the underlying molecular mechanisms are still ill-defined. Neutrophils die because of programmed cell death or apoptosis. However, treatment with inhibitor of caspases, which are responsible for the majority of apoptotic cell deaths, does not prevent the spontaneous death of neutrophils. PKB/Akt possesses prosurvival and antiapoptotic activities in a variety of cells. In this study, we show that Akt activity decreases dramatically during the course of neutrophil death. Both phosphatidylinositol 3-kinase and Akt inhibitors enhance neutrophil death. Conditions delaying neutrophil death, such as treatment with granulocyte–macrophage colony-stimulating factor, granulocyte colony-stimulating factor, or IFN-γ, restore Akt activity. Finally, we demonstrate that neutrophils depleted of PTEN, a phosphatidylinositol 3′-phosphatase that negatively regulates Akt activity, live much longer than WT neutrophils. Thus, we establish Akt deactivation as a causal mediator of neutrophil spontaneous death.
TRP Channels: Molecular Diversity and Physiological Function
Authors: NISHIDA MOTOHIRO , HARA YUJI , YOSHIDA TAKASHI , INOUE RYUJI , MORI YASUO
Published: September 2006

Calcium ions (Ca2 +) are particularly important in cellular homeostasis and activity. To elicit physiologically relevant timing and spatial patterns of Ca2+ signaling, ion channels in the surface of each cell precisely control Ca2+ influx across the plasma membrane. A group of surface membrane ion channels called receptor‐activated cation/Ca2+ channels (RACCs) are activated by diverse cellular stimuli from the surrounding extracellular environment via receptors and other pathways such as heat, osmotic pressure, and mechanical and oxidative stress. An important clue to understanding the molecular mechanisms underlying the functional diversity of RACCs was first attained by molecular identification of the transient receptor potential (trp) protein (TRP), which mediates light‐induced depolarization in Drosophila photoreceptor cells, and its homologues from various biological species. Recent studies have revealed that respective TRP channels are indeed activated by characteristic cellular stimuli. Furthermore, the involvement of TRP channels has been demonstrated in the signaling pathways essential for tissue‐specific functions as well as ubiquitous biological responses, such as cell proliferation, differentiation, and death. These findings encourage the usage of TRP channels and their signalplexes as powerful tools for developing novel pharmaceutical targets.
Sensitization of Coronary α ‐Adrenoceptor Vasoconstriction in the Prediabetic Metabolic Syndrome
Authors: DINCER Ü. DENIZ , ARAIZA ALBERTO G. , KNUDSON JARROD D. , MOLINA PATRICIA E. , TUNE JOHNATHAN D.
Published: September 2006

Objective: This study tested whether α ‐adrenoceptor‐mediated coronary vasoconstriction is augmented in the metabolic syndrome and is accompanied by the alteration of specific α1‐ and α2‐coronary adrenoceptors.

Methods: Studies were conducted in control and chronically high‐fat‐fed (6 weeks of 60% calories from fat) dogs with metabolic syndrome. Alterations in coronary α 1B‐, α1D‐, and α2A‐adrenoceptor mRNA and protein expression were examined by real‐time PCR and Western analyses, respectively. Coronary blood flow and its response to intracoronary infusion of either the α1‐adrenoceptor agonist methoxamine (0.1–3 mg) or the α2‐adrenoceptor agonist BHT‐933 (0.1–3 mg) were measured in anesthetized dogs.

Results: Basal plasma epinephrine and norepinephrine levels were higher in the high‐fat‐fed dogs compared to controls. Real‐time PCR revealed no alterations of coronary artery or arteriole α1B‐, α1D‐, and α2A‐adrenoceptor mRNA expression. However, Western blot analysis showed a significant decrease in α2A‐adrenoceptor protein density with no change in α1B‐ or α 1D‐adrenoceptors. Methoxamine and BHT‐933 produced dose‐dependent decreases in coronary blood flow, but the decrease in coronary flow to methoxamine was significantly greater (∼ 20%) in dogs with the metabolic syndrome. No differences in the coronary flow response to BHT‐933 were noted.

Conclusions: These results indicate that the metabolic syndrome is associated with sensitization of α1‐ and α2‐adrenoceptor signaling that could significantly limit control of coronary blood flow when the sympathetic nervous system is activated.
Lymph Flow, Shear Stress, and Lymphocyte Velocity in Rat Mesenteric Prenodal Lymphatics
Authors: DIXON J. BRANDON , GREINER STEVEN T. , GASHEV ANATOLIY A. , COTE GERARD L. , MOORE JAMES E. , ZAWIEJA DAVID C.
Published: September 2006

Objective: To measure lymphocyte velocity, lymphatic contraction, and shear stress in phasically contracting lymphatics in situ.

Methods: A high‐speed video system was used to capture multiple contraction cycles in rat mesenteric lymphatic preparations. The images were analyzed to determine fluid velocity, volume flow rate, wall shear stress, and retrograde flow.

Results: Lymphocyte density and flux varied from 326 to 35,500 cells/μ L and 206 to 2030 cells/min, respectively. Lymphatics contracted phasically, with a mean diameter 91 ± 9.0 μ m and amplitudes of 39%. Lymph velocity varied with the phasic contractions in both direction and magnitude with an average of 0.87 ± 0.18 and peaks of 2.2–9.0 mm/s. The velocity was ∼ 180° out of phase with the contraction cycle. The average lymph flow was 13.95 ± 5.27 μ L/h with transient periods of flow reversal. This resulted in an average shear of 0.64 ± 0.14 with peaks of 4–12 dynes/cm2.

Conclusions: High‐speed lymphocyte tracking provided the spatial and temporal resolution to measure lymphocyte flux throughout the phasic contraction. Poiseuille flow was a reasonable model for estimating wall shear stress through most of the phasic contraction cycle of the intervalvular lymphatic segments. Shear rate was low but had large variations in magnitude compared to that seen in blood vessels.
Finite simultaneous bending
Authors: Chamanara Reza
Published: September 2006

We construct a finite approximation to a Jordan curve with the given pair of bending measured laminations.
Global Organization and Function of Mammalian Cytosolic Proteasome Pools: Implications for PA28 and 19S Regulatory Complexes
Authors: Shibatani Toru , Carlson Eric J. , Larabee Fredrick , McCormack Ashley L. , Früh Klaus , Skach William R.
Published: September 2006

Proteolytic activity of the 20S proteasome is regulated by activators that govern substrate movement into and out of the catalytic chamber. However, the physiological relationship between activators, and hence the relative role of different proteasome species, remains poorly understood. To address this problem, we characterized the total pool of cytosolic proteasomes in intact and functional form using a single-step method that bypasses the need for antibodies, proteasome modification, or column purification. Two-dimensional Blue Native(BN)/SDS-PAGE and tandem mass spectrometry simultaneously identified six native proteasome populations in untreated cytosol: 20S, singly and doubly PA28-capped, singly 19S-capped, hybrid, and doubly 19S-capped proteasomes. All proteasome species were highly dynamic as evidenced by recruitment and exchange of regulatory caps. In particular, proteasome inhibition with MG132 markedly stimulated PA28 binding to exposed 20S α-subunits and generated doubly PA28-capped and hybrid proteasomes. PA28 recruitment virtually eliminated free 20S particles and was blocked by ATP depletion. Moreover, inhibited proteasomes remained stably associated with distinct cohorts of partially degraded fragments derived from cytosolic and ER substrates. These data establish a versatile platform for analyzing substrate-specific proteasome function and indicate that PA28 and 19S activators cooperatively regulate global protein turnover while functioning at different stages of the degradation cycle.
A Phg2-Adrm1 Pathway Participates in the Nutrient-controlled Developmental Response inDictyostelium
Authors: Cherix Nathalie , Froquet Romain , Charette Steve J. , Blanc Cédric , Letourneur François , Cosson Pierre
Published: September 2006

Dictyostelium amoebae grow as single cells but upon starvation they initiate multicellular development. Phg2 was characterized previously as a kinase controlling cellular adhesion and the organization of the actin cytoskeleton. Here we report that Phg2 also plays a role during the transition between growth and multicellular development, as evidenced by the fact that phg2 mutant cells can initiate development even in the presence of nutrients. Even at low cell density and in rich medium, phg2 mutant cells express discoidin, one of the earliest predevelopmental markers. Complementation studies indicate that, in addition to the kinase domain, the core region of Phg2 is involved in the initiation of development. In this region, a small domain contiguous with a previously described ras-binding domain was found to interact with the Dictyostelium ortholog of the mammalian adhesion-regulating molecule (ADRM1). In addition, adrm1 knockout cells also exhibit abnormal initiation of development. These results suggest that a Phg2-Adrm1 signaling pathway is involved in the control of the transition from growth to differentiation in Dictyostelium. Phg2 thus plays a dual role in the control of cellular adhesion and initiation of development.
Systematic Deletion and Mitotic Localization of the Nuclear Pore Complex Proteins ofAspergillus nidulans
Authors: Osmani Aysha H. , Davies Jonathan , Liu Hui-Lin , Nile Aaron , Osmani Stephen A.
Published: September 2006

To define the extent of the modification of the nuclear pore complex (NPC) during Aspergillus nidulans closed mitosis, a systematic analysis of nuclear transport genes has been completed. Thirty genes have been deleted defining 12 nonessential and 18 essential genes. Several of the nonessential deletions caused conditional phenotypes and self-sterility, whereas deletion of some essential genes caused defects in nuclear structure. Live cell imaging of endogenously tagged NPC proteins (Nups) revealed that during mitosis 14 predicted peripheral Nups, including all FG repeat Nups, disperse throughout the cell. A core mitotic NPC structure consisting of membrane Nups, all components of the An-Nup84 subcomplex, An-Nup170, and surprisingly, An-Gle1 remained throughout mitosis. We propose this minimal mitotic NPC core provides a conduit across the nuclear envelope and acts as a scaffold to which dispersed Nups return during mitotic exit. Further, unlike other dispersed Nups, An-Nup2 locates exclusively to mitotic chromatin, suggesting it may have a novel mitotic role in addition to its nuclear transport functions. Importantly, its deletion causes lethality and defects in DNA segregation. This work defines the dramatic changes in NPC composition during A. nidulans mitosis and provides insight into how NPC disassembly may be integrated with mitosis.
Prognostic significance of HLA class I expression in osteosarcoma defined by anti‐pan HLA class I monoclonal antibody, EMR8‐5
Authors: Tsukahara Tomohide , Kawaguchi Satoshi , Torigoe Toshihiko , Asanuma Hiroko , Nakazawa Emiri , Shimozawa Kumiko , Nabeta Yuki , Kimura Shigeharu , Kaya Mitsunori , Nagoya Satoshi , Wada Takuro , Yamashita Toshihiko , Sato Noriyuki
Published: September 2006

With the goal of establishing efficacious peptide‐based immunotherapy for patients with bone and soft tissue sarcomas, we previously identified the cytotoxic T lymphocyte‐defined osteosarcoma antigenic gene Papillomavirus binding factor. The present study was designed to determine the status of HLA class I expression in osteosarcoma and other bone and soft tissue sarcomas. Seventy‐four formalin‐fixed paraffin‐embedded specimens of various bone and soft tissue sarcomas, including 33 osteosarcomas, were stained with the anti‐HLA class I monoclonal antibody EMR8‐5, which we recently generated. The expression of HLA class I was lost or downregulated in 46 of these specimens (62%). With respect to osteosarcoma, loss or downregulation of HLA class I expression was seen in 13 (52%) of 25 primary tumors and seven (88%) of eight metastatic tumors. In six of 11 HLA class I‐negative osteosarcoma specimens, the expression of β‐2 microglobulin was also lost. Subsequently the prognostic significance of HLA class I expression was analyzed in 21 patients with osteosarcoma who had completed multidrug neoadjuvant chemotherapy and undergone adequate surgery. Patients with osteosarcoma highly expressing HLA class I showed significantly better overall and event‐free survival than those with HLA class I‐negative osteosarcoma. In contrast, such prognostic significance of HLA class I expression was not found in 15 patients with malignant fibrous histiocytoma of soft tissue. These findings suggest that the class I‐restricted cytotoxic T lymphocyte pathway plays a major role in immune surveillance of patients with osteosarcoma. (Cancer Sci 2006; 97: 1374–1380)
Potential role of natural killer cells in controlling growth and infiltration of AIDS‐associated primary effusion lymphoma cells
Authors: Dewan Md. Zahidunnabi , Terunuma Hiroshi , Toi Masakazu , Tanaka Yuetsu , Katano Harutaka , Deng Xuewen , Abe Hiroyuki , Nakasone Tadashi , Mori Naoki , Sata Tetsutaro , Yamamoto Naoki
Published: September 2006

Natural killer (NK) cells are an important component of the innate immune response against microbial infections and tumors. Direct involvement of NK cells in tumor growth and infiltration has not yet been demonstrated clearly. Primary effusion lymphoma (PEL) cells were able to produce tumors and ascites very efficiently with infiltration of cells in various organs of T‐, B‐ and NK‐cell knock‐out NOD/SCID/γcnull (NOG) mice within 3 weeks. In contrast, PEL cells formed small tumors at inoculated sites in T‐ and B‐cell knock‐out NOD/SCID mice with NK‐cells while completely failing to infiltrate into various organs. Immunosupression of NOD/SCID by treatment with an antimurine TM‐β1 antibody, which transiently abrogates NK cell activity in vivo, resulted in enhanced tumorigenicity and organ infiltration in comparison with non‐treated NOD/SCID mice. Activated human NK cells inhibited tumor growth and infiltration in NOG mice. Our results suggest that NK cells play an important role in growth and infiltration of PEL cells, and activated NK cells could be a promising immunotherapeutic tool against tumor or virus‐infected cells either alone or in combination with conventional therapy. The rapid and efficient engraftment of PEL cells in NOG mice also suggests that this new animal model could provide a unique opportunity to understand and investigate the mechanism of pathogenesis and malignant cell growth. (Cancer Sci 2006; 97: 1381–1387)
ZD6474 induces growth arrest and apoptosis of GIST‐T1 cells, which is enhanced by concomitant use of sunitinib
Authors: Yang Yang , Ikezoe Takayuki , Nishioka Chie , Taguchi Takahiro , Zhu Wei‐guo , Koeffler H. Phillip , Taguchi Hirokuni
Published: September 2006

ZD6474 (Zactima, AstraZeneca, Macclesfield, UK) is an orally available, small‐molecule inhibitor of vascular endothelial growth factor receptor‐2 and epidermal growth factor receptor tyrosine kinases, with additional activity versus rearranged during transfection (RET). This study explored the effect of ZD6474 in gastrointestinal stromal tumor‐T1 (GIST‐T1) cells that possess a gain of function mutation in exon 11 of the c‐KIT gene. ZD6474 induced growth arrest and apoptosis of GIST‐T1 cells in association with blockade of c‐Kit and its downstream effectors, including Akt and extracellular signal‐regulated kinase (ERK). ZD6474 treatment also blocked the mammalian target of rapamycin (mTOR), which lies downstream of Akt and ERK. Interestingly, when ZD6474 was combined with sunitinib (SU11248; Sutent, Pfizer, Kalamazoo, MI, USA), a class III and V receptor tyrosine kinase inhibitor, the ZD6474‐mediated growth inhibition was potentiated in association with further down‐regulation of the mTOR targets p‐p70S6K and p‐4E‐BP‐1. The combination of ZD6474 and sunitinib should be investigated further. (Cancer Sci 2006; 97: 1404–1409)
Characteristic expression of globotriaosyl ceramide in human ovarian carcinoma‐derived cells with anticancer drug resistance
Authors: Kiguchi Kazushige , Iwamori Yuriko , Suzuki Nao , Kobayashi Yoichi , Ishizuka Bunpei , Ishiwata Isamu , Kita Tsunekazu , Kikuchi Yoshihiro , Iwamori Masao
Published: September 2006

The transporter protein genes and lipids in human ovarian carcinoma‐derived KF28 cells with anticancer‐drug‐sensitive properties were compared with those in resistant cells, taxol‐resistant KF28TX, cisplatin‐resistant KFr13, and taxol‐ and cisplatin‐resistant KFr13TX, to identify the molecules required for anticancer‐drug resistance. In accordance with previous reports, taxol and cisplatin resistance was closely correlated with expression of the multidrug resistance 1 and bile acid export pump, and multidrug resistance‐associated protein 2 genes, respectively. In addition, we found a distinct difference in glycosphingolipids between the sensitive and resistant cells. Although GlcCer was the major glycolipid (83.0%) in sensitive cells, GalCer, LacCer and, particularly, Gb3Cer were characteristically increased in all resistant cells, irrespective of whether the resistance was to taxol or cisplatin, and comprised 65–84% of total glycosphingolipids. GM3, which was present at 0.04 µg/mg dry weight in the sensitive cells, showed a twofold increase in the taxol‐resistant cells, but was absent in the cisplatin‐resistant cells. The altered glycolipid composition was proven to be due to enhanced or suppressed expression of the respective sugar transferase genes. In addition, the ceramide moiety of ceramide monohexoside in the sensitive cells constituted 83% of non‐hydroxy fatty acids, but that in the resistant cells comprised 67–74% of α‐hydroxy fatty acids. Thus, cells containing Gb3Cer with α‐hydroxy fatty acids were found to survive selectively in the presence of taxol and cisplatin, and modification of the glycolipid structure was revealed to occur in association with anticancer‐drug resistance. (Cancer Sci 2006; 97: 1321–1326)
Cessation of injection drug use and change in injection frequency: the Chicago Needle Exchange Evaluation Study
Authors: Huo Dezheng , Bailey Susan L. , Ouellet Lawrence J.
Published: September 2006

Aims To examine the effect of a needle exchange program (NEP) on incidence of injection cessation and change in injection frequency; to explore predictors for injection cessation and change in injection frequency; and to assess whether injection quitters transitioned to non‐injected drug use.

Design and setting Between 1997 and 2002, 901 injection drug users (IDUs) were recruited from an NEP program or an area with no NEP in Chicago, Illinois, interviewed for drug use behaviors, tested for HIV and followed for three annual visits. All participants were exposed to prevention services targeting HIV and drug abuse.

Measurements Injection cessation was defined as no injection drug use since the last interview, and changes in the number of injections in a typical month were examined.

Findings Sixteen per cent of study participants reported stopping injection for a median duration of 16 months, and most of them also ceased rather than initiated the use of non‐injected drugs. Those who continued injecting reduced their injection frequency by 12% per year, on average. Independent predictors of injection cessation were infrequent injection at baseline, younger age and injecting with others. NEP use was not associated with injection cessation and change in injection frequency.

Conclusion These results did not support the hypothesis that NEP use influences the frequency of injection over time. One‐sixth of IDUs stopped injection for more than 1 year, providing a substantial window for relapse prevention interventions.
A randomized controlled trial to assess the effects of reimbursing the costs of smoking cessation therapy on sustained abstinence
Authors: Kaper J. , Wagena E. J. , Willemsen M. C. , Van Schayck C. P.
Published: September 2006

Aims  We studied whether reimbursement for smoking cessation treatment (SCT) can increase prolonged abstinence from smoking up to 2 years.

Setting, participants and design  From the general population, we recruited smokers and assigned them randomly to a control group (n = 634) or an intervention group (n = 632). For 6 months, participants in the intervention group could apply for reimbursement and received information regarding the reimbursed SCT. Participants in the control group received no reimbursement or information.

Measurements  In this follow‐up study, prolonged abstinence from smoking was defined as reported being abstinent from at least 7 days before the end of reimbursement until the follow‐up assessment 6 months or 2 years later.

Findings  At 6 months after the end of reimbursement, 18 participants in the control group (2.8%) and 35 participants (5.5%) in the intervention group reported sustained abstinence for at least 6 months [odds ratio (OR) = 2.0, 95% confidence interval (CI) 1.1–3.6]. Two years after the reimbursement period, 10 participants in the control group (1.6%) and 27 participants in the intervention group (4.3%) still reported sustained abstinence (OR = 4.1, 95% CI 1.7–10.2). The overall effectiveness of SCT increased with reimbursement and was 22% in the intervention group and 8% in the control group after 2 years.

Conclusions  Reimbursement may be an effective strategy to increase the prolonged abstinence rate even after 2 years.
Contingency management for treatment of substance use disorders: a meta‐analysis
Authors: Prendergast Michael , Podus Deborah , Finney John , Greenwell Lisa , Roll John
Published: September 2006

Aims  To examine the effectiveness of contingency management (CM) techniques in treating substance use disorders (i.e. illicit drugs, alcohol, tobacco).

Design  Meta‐analysis was used to determine the average effect size and potential moderators in 47 comparisons of the effectiveness of CM from studies based on a treatment–control group design and published between 1970 and 2002.

Findings  The mean effect size (ES) of CM was positive, with a magnitude of d = 0.42 using a fixed effects model. The magnitude of the ES declined over time, following treatment. CM was more effective in treating opiate use (d = 0.65) and cocaine use (d = 0.66), compared with tobacco (d = 0.31) or multiple drugs (d = 0.42). Larger effect sizes were associated with higher researcher involvement, earlier studies and shorter treatment duration.

Conclusions  Study findings suggest that CM is among the more effective approaches to promoting abstinence during the treatment of substance use disorders. CM improves the ability of clients to remain abstinent, thereby allowing them to take fuller advantage of other clinical treatment components.
A detailed study of time‐dependent changes in human red blood cells: from reticulocyte maturation to erythrocyte senescence
Authors: Gifford Sean C. , Derganc Jure , Shevkoplyas Sergey S. , Yoshida Tatsuro , Bitensky Mark W.
Published: September 2006

The use of microfabrication technology in the study of biological systems continues to grow rapidly in both prevalence and ascendancy. Customised microdevices that provide superior results than traditional macroscopic methods can be designed in order to investigate specific cell types and cellular processes. This study showed the benefit of this approach in precisely characterising the progressive losses of surface area and haemoglobin (Hb) content by the human red blood cell (RBC), from newborn reticulocyte to senescent erythrocyte. The high‐throughput, multiparametric measurements made on individual cells with a specialised microdevice enabled, for the first time, delineation and quantification of the losses that occur during the two stages of the human RBC lifespan. Data acquired on tens of thousands of red cells showed that nearly as much membrane area is lost during the 1–2 d of reticulocyte maturation (c. 10–14%) as in the subsequent 4 months of erythrocyte ageing (c. 16–17%). The total decrease in Hb over the red cell lifespan is also estimated (c. 15%) and a model describing the complete time‐course of diminishing mean RBC area and Hb is proposed. The relationship between the losses of Hb and area, and their possible influence on red cell lifespan, are discussed.