bluuebunny/crossref_metadata_2025 huggingface dataset:
STACKING INTERACTION IN PYRAZINE DIMER
Authors: MISHRA BRIJESH KUMAR , SATHYAMURTHY N.
Published: September 2006

The structure and stability of pyrazine dimer in different orientations have been investigated using second- and fourth-order Møller–Plesset perturbation theory (MP2, MP4) and coupled-cluster singles and doubles with non-iterative perturbative triples method [CCSD(T)] with various basis sets (6-31G*, 6-311G**, 6-311++G**, cc-pVDZ, aug-cc-pVDZ, cc-pVTZ, and aug-cc-pVTZ). With the largest basis set (aug-cc-pVTZ) at the MP2 level of theory, the calculated binding energies (basis set superposition error corrected) for the sandwich, N–N axial-displaced, lateral-displaced, cross-displaced, T-shaped ( TN-ringand TH-ring), and wedge-shaped ( WN–Cand WC–C) geometries are found to be 3.01, 4.18, 4.63, 5.92, 4.54, 2.78, 2.89, and 3.23 kcal/mol, respectively. Although MP2 calculations predict the cross-displaced geometry to be the most stable one, MP4 and CCSD(T) calculations show the most stable geometry to be T-shaped ( TN-ring), with a center-of-mass separation of 4.2 Å. Dispersion interaction seems to be the major source of attraction in all the geometries considered, while the nature of electrostatic interaction depends on the mutual orientation of the two rings.
CONFORMATIONAL STABILITY, MOLECULAR STRUCTURE, AND INTRAMOLECULAR HYDROGEN BONDING OF THENOYLTRIFLUOROACETONE
Authors: TAYYARI SAYYED FARAMARZ , NEKOEI ABDO-REZA , VAKILI MOHAMMAD , HASSANPOUR MASOUD , WANG YAN ALEXANDER
Published: September 2006

Complete conformational analysis of all possible keto and enol forms of thenoyltrifluoroacetone (TTFA) was carried out using density functional theory with the B3LYP functional and the 6-31G**, 6-311G**, and 6-311++G** basis sets. In addition, the geometries and energies of the four most stable chelated conformers and their corresponding open structures were obtained at the MP2/6-31G** level of theory. The energy differences between the four stable chelated enol conformers, in the gas phase, calculated at the B3LYP levels are negligible. However, calculations at the MP2 level indicate that the B2 conformer (the hydroxyl group in the - CF 3 side) is significantly more stable than others, in agreement with the X-ray diffraction results. The calculated intramolecular hydrogen bond (IHB) energy E HB and the strength of the bond have been compared, and an imperfection in the prevalent method of evaluating E HB has been perceived. The IHB of TTFA was compared with those in several β-dicarbonyls.
Deformation of Sedimented Mats of Polyethylene Single Crystals
Authors: Ohde Yoshihito , Miyaji Hideki , Asai Kenjiro
Published: September 2006

By pressing the hot sedimented mats of polyethylene single crystals, fiber texture, in which chain axes are oriented in the direction of deformation, is formed through the following stages. The first, inter-lamellar slip develops because of the scarcity of tie-molecules, and at the same time, intralameller slip,i.e.<001> slip and/or chain tilting result in a decrease of lamellar thickness and expansion of a unit cell. The second, locally concentrated slips occur in a mat instead of the homogeneous <001> slip, and blocks of lamellar fragments rotate so as to decrease the thickness of a mat. Throughout these processes the lamellar crystallites behave as the structural units. The change of density of the mat is well explained by these modes of deformation. The increase of the unit cell dimensions by the deformation, which is anisotropic in the direction perpendicular to the chain axis, is observed. A qualitative discussion on <001> slip is made.
Interface Properties of Al2O3-Ge Structure and Characteristics of Al2O3-Ge MOS Transistors
Authors: Iwauchi Shigeki , Tanaka Toshio
Published: September 2006

The interface properties of Al2O3-Ge structure formed on germanium wafers by DC reactive sputtering are evaluated.
The fast interface states are diminished by subjecting the sample to heat treatment in an inert gas flow.
The interface state density is estimated to be typically less than 4×1011 state/cm2-eV from the shift of the flat-band voltage with temperature as originally adopted by Gray and Brown.
From the measurement of the parallel conductance of the MOS structure, the electron capture cross section of the trap located at the interface is estimated to be about 0.9×10-17 cm2 using the tunnelling model of Preier, and about 1×10-18 cm2 using the surface potential fluctuation model of Nicollian and Goetzberger. With reactively sputtered Al2O3 films as a gate insulator, n-channel germanium MOS transistors are made with a high effective mobility. The effective mobility is typically more than 2000 cm2/V-sec and the gate threshold voltage is about 1 volt or less.
High Excitation Luminescences of AlxGa1-xP Compound Alloy
Authors: Sonomura Hajimu , Nishimura Takayuki , Horinaka Hiromichi , Miyauchi Takeshi
Published: September 2006

High excitation photoluminescences and high injection electroluminescences for the ternary compound alloy Al
x
Ga1-x
P have been measured. Emission peaks near the band edge, explained as being due to annihilation of excitons bound to N (nitrogen) isoelectronic impurities, have been observed for both luminescences at 80 K. The peaks shift little with increasing composition factor up to the middle composition region, and then disappear at larger factors. These effects can be explained by the hypothesis that an N atom which has a bond with an Al atom cannot serve as an electron trap, and that a number of GaP clusters as large as 100 Å estimated from the radius of the exciton are formed in the alloy, while the N isoelectronic impurity acts as a recombination center in the clusters only.
Electroluminescence in Polyethylene Terephthalate (PET). II. AC Voltage
Authors: Kojima Kenzo , Takai Yoshiaki , Ieda Masayuki
Published: September 2006

Electroluminescence in polyethylene terephthalate (PET) was observed under AC voltages. The electroluminescence was found to be controlled by the injection of electrons from the Al electrode, together with the space charge accumulation. The occurrence of the injection and accumulation of electrons was demonstrated by thermally-stimulated current analysis. The significant modification of the internal field by the space charge resulted in an asymmetrical waveform of the electroluminescence in each half-cycle of the AC voltage.
Kinetics of Antimony Doping in Silicon Molecular Beam Epitaxy
Authors: Tabe Michiharu , Kajiyama Kenji
Published: September 2006

A new kinetic model for Sb doping into the Si MBE layer is proposed. In this model, Sb doping steps are assumed as follows: a fraction of impinging Sb4 molecules adsorbs on the growing Si surface (adlayer) and monoatomic Sb desorbs from the adlayer into vapor; a fraction of monoatomic Sb in the adlayer is incorporated into the bulk, so that surface-concentration of Sb atoms may be in equilibrium with bulk-concentration of Sb.
According to this model, calculated results successfully represent the present experimental data on relations between incident Sb4 flux, Sb concentration in the adlayer and that in bulk. As a result, it is indicated that doping levels in MBE layers are uniquely determined by Sb concentration in the adlayer, and not by Sb4 flux/Si flux ratio, when Si growth rate is lower than 1 Å/s.
Synthesis of A15Nb3Ge by Pulsed Laser Annealing
Authors: Asano Hidefumi , Nakamura Kiko , Terada Akira
Published: September 2006

Poly-crystalline A15Nb3Ge with an abnormally small lattice parameter of 5.115 Å has been synthesized by illuminating Q-switched ruby laser pulses onto sputter-deposited Nb3Ge films. A new kind of A15 phase growth was detected in the X-ray diffraction patterns for films having different structures (amorphous Nb3Ge, a mixture of amorphous Nb3Ge and A15Nb3Ge, and a mixture of A15Nb3Ge and hexagonal Nb5Ge3). Volume increased in the new A15 phase due to the repeated laser pulse illumination. Electron microscopic studies also confirmed the growth of the new A15 phase. In addition, oxygen diffusion within a near-surface layer about 1000 Å thick was detected in films illuminated in air. The maximum of superconducting transition onset was 8.5 K. These results are discussed in this paper from the standpoint of the surface melting model of the pulsed laser annealing.
Elastooptic Properties of InP
Authors: Suzuki Nobuo , Tada Kunio
Published: September 2006

All of the elastooptic coefficients p
11, p
12 and p
44 in InP have been measured in the wavelength region from 1.06 µm to 1.50 µm at room temperature. The measurement has been carried out by the Dixon-Cohen method, but correction of acoustic wave diffraction, which causes large error in a measurement especially under the Raman-Nath diffraction condition, is made using a simple approximation. InP has a large acoustooptic figure of merit comparable to that of GaAs. Using the obtained elastooptic coefficients, dispersion of strain-optic coefficients has been derived. The deformation potentials estimated from this analysis are a≃-(11±3) eV, b≃-(1.5±1.5) eV and d≃-(2.8±1.2) eV.
Meissner Effect and Magnetic Field Dependence of Cu Clad Nb in mK Region
Authors: Oda Yasukage , Sumiyama Akihiko , Nagano Hiroshi
Published: September 2006

The Meissner region induced by the proximity effect in a thick Cu clad Nb wire is measured down to 4.5 mK. It is found that the thickness ρ of the Meissner region in Cu increases with decreasing temperature in proportion to T
-1/2. The magnetic field dependence of ρ is also studied in this temperature region. It is found that ρ decreases in proportion to ln H except for the very low field region, if ρ is sufficiently smaller than the thickness of Cu. And if ρ becomes comparable to the thickness of Cu, an anomalous behaviour is observed.
Uniaxial Stress and Temperature Dependences of Photoluminescence in GaAs1-xPx
Authors: Narita Shin-ichiro , Kubota Takeshi , Kobayashi Michihiro
Published: September 2006

The uniaxial stress and temperature dependences of the photoluminescence in GaAs1-x

P

x
(x≃0.38) are studied and three kinds of photoluminescence are observed. One of them is attributed to the surface anomaly and the other two to annihilation of the bound excitons and donor-acceptor pair recombination. By combining the results of the uniaxial stress effect and the temperature change of the photoluminescence, the transition mechanisms for the luminescence are discussed.
On the Measurement of Visco-Elastic Properties of Matters by the Mössbauer Effect
Authors: Fujita Francisco Eiichi
Published: September 2006

A technique to measure the visco-elastic properties of materials by using the Mössbauer effect is proposed. Assuming that a spring coil specimen is attached to the transducer of Mössbauer spectrometer, which gives a sinusoidal Doppler motion between the gamma ray source and the absorber, the visco-elastic vibration of the specimen is calculated and the mechanical resonance conditions are found. When the gamma ray source and absorber are connected to the visco-elastic system, the Mössbauer pattern will be subjected to a modulation, from which the elastic constant and the viscosity of the specimen can be measured, especially from the mechanical resonance condition. A variety of ways of connection between the mechanical and Mössbauer system are considered and applications of the technique are discussed.
Plasma Polymerized Films for Optical Recording
Authors: Asano Yoshihiro , Yamazaki Hiroki , Morinaka Akira
Published: September 2006

Metals containing plasma polymerized films have been investigated as media for laser thermal recording. The Te containing plasma polymerized carbon disulfide films (CS2–Te) and Bi containing plasma polymerized carbon disulfide films (CS2–Bi) are suitable for recording with respect to melting and vaporization, because they have low vaporizing temperature and low heat conductivity. In particular, the CS2–Te unprotected antireflection structure showed the highest sensitivity. On the other hand, the CS2–Te protective antireflection structure showed a lower sensitivity than the unprotected structure, but is preferable from the viewpoint of its high stability. The Te containing plasma polymerized styrene film is suitable for recording with respect to crystallization, because it shows a large optical change due to crystallization.
Time-Resolved Spectral Measurement in Hollow Cathode Discharge Tubes by Photon-Counting Method
Authors: Kimura Muneyasu
Published: September 2006

A microcomputer-controlled photon counting system using a digital sampling method has been developed to perform the spectral measurement of weak lines emitted from Ne atoms and ions excited by square-wave voltage pulses in hollow-cathode discharge tubes with sufficient sensitivity and accuracy. The characteristic features of the system are, 1) the high-voltage pulse generator and photon counter are operated synchronously, 2) the background noise and dark current of the photomultiplier are effectively eliminated by the use of two sampling gates, 3) even when the scanning range is greatly expanded, fluctuation of the gate position remains small. It has been observed using the system that the rise time of the intensity of a neutral line of Ne is generally shorter than that of an ionic line in pulsed hollow-cathode discharge.
Electrification of Polymer Powders after Passage through Metal Pipes
Authors: Masui Noriaki , Murata Yuji
Published: September 2006

The electrification of polymer powder transported through straight copper pipe and copper pipes with 45° and 90° elbows (0.02 m in internal diameter) was studied at a particle speed v=7 m/s∼30.8 m/s and a solid load ρ=0.002 kg/m3∼15 kg/m3. The charge/mass ratio q of the powder passing through an elbow pipe was from 15 to 20 times larger than that in a 1m-long straight pipe. With elbow pipes, it was found that the charge on the powder Q(C) was mostly generated by the first collision with the inner wall of the bend in the pipe. The impact areas S(m2) of the particles in the elbow pipes were calculated at low ρ and high v, and the charge density σ(Q/S C/m2) was found to be constant in spite of the variation in ρ, v and the shape of the pipes.
Thermal Boundary Layer Effects on Mass Sampling from a Shock Tube
Authors: Teshima Koji , Deguchi Motoaki , Takahashi Norio
Published: September 2006

The time-of-flight method was applied to the study of thermal boundary layer effects on the sampled gas in a shock-tube mass-sampling system. The effective stangnation temperatures measured by this method agree well with those calculated on the basis of a simple gas-dynamic model for orifice flow through a developing thermal boundary layer in a stagnation Reynolds number range larger than 400, The effect of change in the stagnation temperature on the density of the sample gas was also examined, and the observed density was found to be consistent with the time history of the measured effective stagnation temperature.
Experimental Verification of the Small-Signal Theory of the Lateral Photovoltaic Effect in MOS Structures
Authors: Shikama Tomokazu , Hayashi Keiji , Niu Hirohiko , Takai Munezo
Published: September 2006

The lateral photovoltage (LPV) in MOS structures is measured as a function of gate voltage and irradiation position. In the weak and strong inversion region of the interface state, the LPV can be explained well by a theory which is essentially the same as that presented for p-n junctions. In contrast to this, in the region from weak inversion to the depletion state, behaviors of the LPV inexplicable by this theory have been observed, i.e. in this region of the interface state, the LPV in almost all cases is not proportional to the power of the irradiation, and depends on its chopping frequency.
In the course of the experimental verification of this theory, the principle of the lateral photovoltaic method of measuring the sheet conductivity of the inversion layer, and the leakage conductance between the inversion layer and the substrate, has been established. The advantages of this LPV method are also discussed.
LPE Growth and Surface Morphology of InxGa1-xAsyP1-y (y≤0.01) on (100) GaAs
Authors: Hiramatsu Kazumasa , Tomita Kazuyoshi , Sawaki Nobuhiko , Akasaki Isamu
Published: September 2006

The effects of the growth conditions (growth time, growth temperature and melt concentration) on the surface morphology of an LPE layer of In
x
Ga1-x
As
y
P1-y
(y≤0.01) on a (100)GaAs substrate are studied. The change in morphology originates from the relation between the growth temperature (T
g) and the equilibrium saturation temperature (T
s) of the source melt, which is in equilibrium with the quaternary solid but is not in equilibrium with the GaAs substrate. The equilibrium temperature was determined from growth layer thickness data, as well as by analysing the phase diagram. It was found that partial growth of the quaternary layer can take place on GaAs even at T
g>T
s, and this is supported by partial melt-back of the substrate. A mirror-like smooth surface was obtained even if the supersaturation Δ
T was as low as 1°C.
A Study of Deep Levels in MOCVD-Grown InP/Semi-Insulating InP Structure
Authors: Ogura Mototsugu , Mizuta Masashi , Hase Nobuyasu , Kukimoto Hiroshi
Published: September 2006

Deep levels in undoped n-type InP epitaxial layers grown by MOCVD on Fe-doped InP substrates were investigated by DLTS and photo-excited DLTS. Two main electron traps, F1 and F2, were observed in the films. The concentration profile of F1 seems to be related to that of donors. The concentration of F2 increases as the substrate is approached, suggesting the out-diffusion of Fe from the Fe-doped substrate. The activation energy E
n and the carrier capture cross section σn were found to be 0.48 eV and ∼6×10-19 cm2 respectively for F1; and 0.78 eV and 10-20∼10-21 cm2 respectively for F2 in the temperature range investigated. Another level was also detected in the Fe-doped substrate, and its E
n and σ∞ were found to be 0.24 eV and 2×10-16 cm2, respectively. We speculate that either or both of these F1 and F2 traps are the origin of the substantial looping phenomenon in the drain I/V characteristics previously observed in InP MESFETs.
Degradation of Sodium-Polymethacrylate and Sodium-Carboxymethyl Cellulose in Dilute Aqueous Solution
Authors: Saita Takao
Published: September 2006

It is shown that Na–PMA and Na–CMC molecules in dilute aqueous solution are degraded during the usual viscosity measurements with a capillary viscometer, and a solution exposed to UV light exhibits an optical absorption maximum at about 270 nm. Polymer degradation proceeds even with time of rest alone, and the rate constant of the degradation increases with decreasing polymer concentration. Consequently, it is shown that the reduced viscosity of a solution of a considerably degraded polymer exhibits a maximum value at a finite concentration, below which the reduced viscosity decreases.
A Nemurical Analysis of the Poschenrieder Lens in Conjunction with a Time-of-Flight Atom-Probe
Authors: Sakai Akira , Sakurai Toshio
Published: September 2006

We have calculated the trajectories and flight time of ions in a time-of-flight atom-probe incorporated with the Poschenrieder lens. The values of the flight time and beam spreading at the detector have been calculated for various incident conditions.
Low-Temperature Growth of Silicon Dioxide Film by Photo-Chemical Vapor Deposition
Authors: Tarui Yasuo , Hidaka Junichi , Aota Katsumi
Published: September 2006

Silicon dioxide films have been prepared from monosilane and oxygen gases using a low-pressure mercury lamp. The deposition rate is increased with UV irradiation and the activation energy is reduced to as low as 0.22 eV. The contribution of the 254 nm light to the deposition is concluded to be very small. The refractive index of the deposited film is 1.44∼1.46. The infrared absorption peaks related with Si–H bonding do not appear in the photo-CVD film.
A Pinhole Camera with Microchannel Plates for Hot Electron Spatial Distribution Measurement
Authors: Yamaguchi Naohiro , Aoki Sadao , Kiwamoto Yasuhito , Oshiba Mitsuo , Saito Teruo , Miyoshi Syoichi
Published: September 2006

A sensitive X-ray pinhole camera with microchannel plates (MCPs) has been constructed and successfully used to obtain X-ray images of hot electron distributions produced by electron cyclotron resonance heating in the thermal barrier region of the axisymmetrized tandem mirror GAMMA 10. Tomographic techniques have been applied to reconstruct a 2-dimensional X-ray intensity distribution. It is found that hot electrons are accumulated on the magnetic axis in a disc-like shape with a full width at half maximum (FWHM) diameter of about 25 cm.
On the Electrochromism of Evaporated V2O5 Films
Authors: Fujita Yoshitaka , Miyazaki Katsuhiro , Tatsuyama Chiei
Published: September 2006

The electrochromism of amorphous V2O5 thin films prepared by the vacuum evaporation of V2O5 powder was studied through optical absorption, XPS and SIMS measurements. The films were colored and bleached with the aid of an electrolyte consisting of lithium perchlorate (LiCLO4·3H2O) in propylene carbonate (CH3CHOCOOCH2). The as-grown films were yellow, like V2O5 powder, while the colored films were greenish-gray, like VO2 powder. The XPS spectra of the O1s and V2p3/2 core levels of the as-grown films matched those of V2O5 powder, while those of the colored films were similar to those of VO2 powder. SIMS measurement revealed that Li+ ions are introduced into the films by coloration and expelled by bleaching. From these results, it is concluded that the coloration of a-V2O5 films is due to a change in the molecular state from V2O5 to VO2. This change is caused by the double injection of electrons and Li+ ions into the films.
Dependence of Temporal Behavior of Conoscopic Figures in Nematic Liquid Crystals on Initial Alignment
Authors: Yamashita Masafumi , Kurihara Makoto , Hisada Eiko , Tako Toshiharu , Ishiguro Kozo
Published: September 2006

How the bound force between the boundary surface and the aligned liquid crystal molecules affects the formation of the conoscopic figure after the electric field is turned on and turned off is studied in twisted thin film and homogeneous thin film. The formation of the conoscopic figure depends strongly on the initial basic alignment (twisted or homogeneous) and depends on the elastic modulus, but its temporal behavior depends only slightly on the pretilt angle (3 degrees or 30 degrees) and the coefficient of viscosity. The temporal change of the deformations obtained in the experiment is compared with the change in the deformations calculated from a Voigt model in the rheological theory, and qualitative agreement is obtained.
The Staebler-Wronski Effect in Hydro-Fluorinated Amorphous Silicon Prepared Using the Intermediate Species SiF2
Authors: Uesugi Takashi , Ihara Hisanori , Matsumura Hideki
Published: September 2006

The change in conductivity produced by irradiation with light, the so-called Staebler-Wronski effect (S-W effect), was studied experimentally in a new type of hydro-fluorinated amorphous silicon (s-Si:F:H) prepared from a mixture of the intermediate species SiF2 and gaseous H2. The magnitude of the S-W effect was observed as a function of the light intensity and the Fermi-level position. It was found that the S-W effect in the new a-Si:F:H is much smaller than that in conventional hydrogenated amorphous silicon (s-Si:H) prepared from gaseous SiH4, and that the magnitude of the S-W effect is a function of the substrate temperature during deposition.
Solid-State Reaction between Manganese Thin Films and Silicon carbide
Authors: Okajima Yoshiaki , Miyazaki Kunio
Published: September 2006

The solid-state reaction between Mn thin films and SiC ceramic was investigated at annealing temperatures between 450 and 600°C using Auger electron spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction. Carbon was found to diffuse readily into the manganese layer after annealing for 1 min at 450°C, forming manganese carbide; and the silicon thus released interdiffuses with manganese above 550°C to form manganese silicide. The activation energy for the formation of the manganese carbide was 15.5 kcal/mol.
Opposite-Polarity Residual Voltage in Low-Density Polyethylene Films between Plane Electrodes
Authors: Kitani Isamu , Hirano Tomohisa , Arii Kiyomitsu
Published: September 2006

A high residual voltage of polarity opposite to that of the applied voltage was observed in a low-density polyethylene film inserted between plane polished brass electrodes, though the polarity in a specimen with evaporated metal electrodes was the same and the value was lower. As an example, the residual voltage with brass electrodes grew to 100 V even after the circuit was shorted for 1 hour after application of 6 kV for 1 minute.
A computer analysis required the following assumption of charge distributions to explain the observed opposite-polarity residual voltage. The injected negative and positive mobile charges, of dispersive mobility, decrease with the distance from source to sink, and a large amount of homo-frozen charges are concentrated in the regions near the electrodes. These charge distributions are related to the existence of thin air layers between the specimen and the brass electrodes.
A Simple Statistical Theory of the Stress-Strain Relation in Plasticity
Authors: Chen Y. M.
Published: September 2006

A simple derivation of the stress-strain relation in plasticity from the microscopic point of view is given. For simplicity, only macroscopically homogeneous and isotropic solids which are in thermal equilibrium with a larger system and subjected to uniform external forces are considered. Furthermore, dissipation, time-dependent properties and quantum effects are neglected. The displacement of each molecule (or of each cluster of molecules) in a solid is described by the displacement of a few corresponding nodal points in a large coherent flexible network. Then, with the physical properties of dislocations included, the equivalent network is treated statistically by using the classical equilibrium statistical mechanics. Although such a simple theoretical model is used and many non-trivial simplifications are made in the derivation, qualitative agreement is found between the derived and experimentally measured stress-strain relations.
New Technique of Electrostatic Single-Probe in Combustion Products
Authors: Yanagi Tetsui
Published: September 2006

When an electrostatic single-probe was used in the combustion product, an electron current vs. probe voltage characteristic has not been able to be obtained correctly for lack of ability of a reference electrode to collect a large amount of saturated positive-ion current. This difficulty is solved by the method of flowing a constant current through the reference electrode and of compensating the probe current by the current collected by the third electrode inserted into the reaction zone, to which the sufficiently high voltage is added. The electron currents for fixed probe voltage which are obtained by the aid of the devised technique vary nearly proportionally with the probe length, as well as the positive-ion current does. This fact assures the true single-probe operation to the devised technique.
A Modified Pound-Watkins Type NMR Spectrometer at 100 Mc Region
Authors: Horai Kazumi , Horikawa Naoaki , Kajikawa Ryoichi , Makino Fumiyoshi
Published: September 2006

A simple NMR spectrometer successfully operated in the frequency region from 80 to 110 MC is described. The main feature of this spectrometer is an application of Pound-Watkins type marginal oscillator to such a high frequency band with a long flexible NMR probe which was proved to be versatile in measuring magnetic field strength in a narrow space.
Behaviors of Electrostatic Cylindrical Probe in Combustion Products
Authors: Yanagi Tetsui
Published: September 2006

To establish the diagnostics of an electrostatic probe in the high pressure plasma, the dependence of the probe characteristics on the probe length and temperature was experimentally investigated in the plasma of the combustion product by using a single-probe technique. The nearly linear dependence of the probe current on the probe length was observed to a fine and long probe, from which the effective probe length is determined to eliminate the end effect. By lowering the probe temperature from that of the ambient gas the probe current for a fixed voltage decreased. It was also ascertained, however, that the fine and long probe used in the combustion product can be regarded approximately as the probe which has the same temperature as the ambient gas and has no end effect. The dependence of the probe current on the probe temperature is explained by taking into consideration the thermal boundary layer surrounding the probe.
Challenged by Complexity: My Twentieth Century in Immunology
Authors: Doherty Peter C.
Published: September 2006

My research career has focused on complex experimental systems, principally virus-induced infectious processes. I have always run my own experimental program and never had a major mentor, although I have had many great colleagues. After graduating from the School of Veterinary Science at the University of Queensland, Australia, I worked for nine years on diseases of domestic animals. During that interval I completed a part-time PhD at the University of Edinburgh while employed as an experimental neuropathologist. Returning to the John Curtin School of Medical Research in Canberra, I focused on cell-mediated immunity, started to work seriously with mice, and thus became both an immunologist and a basic medical scientist. It was there in 1973 that Rolf Zinkernagel and I discovered MHC I–restricted CD8+T cell recognition, a finding that, together with the “single T cell receptor/altered self” hypothesis that we developed to explain our results, led to the 1996 Nobel Prize for Physiology or Medicine. Part of my focus since then has been to communicate the societal value and power of science to the broader community. As my scientific life is not yet over, I confine the present historical account to the twentieth century.
Advanced glycation end products induce apoptosis in fibroblasts through activation of ROS, MAP kinases, and the FOXO1 transcription factor
Authors: Alikhani Mani , MacLellan Christine M. , Raptis Markos , Vora Siddarth , Trackman Philip C. , Graves Dana T.
Published: September 2006

Advanced glycation end products (AGEs) are elevated in aged and diabetic individuals and are associated with pathological changes associated with both. Previously we demonstrated that the AGE Nε-(carboxymethyl)lysine (CML)-collagen induced fibroblast apoptosis through the cytoplasmic and mitochondrial pathways and the global induction of proapoptotic genes. In the present study we investigated upstream mechanisms of CML-collagen-induced apoptosis. CML-collagen induced activation of the proapoptotic transcription factor FOXO1 compared with unmodified collagen. When FOXO1 was silenced, CML-collagen-stimulated apoptosis was reduced by ∼75% compared with fibroblasts incubated with nonsilencing small interfering RNA, demonstrating the functional significance of FOXO1 activation ( P < 0.05). CML-collagen but not control collagen also induced a 3.3-fold increase in p38 and a 5.6-fold increase in JNK(1/2) activity ( P < 0.05). With the use of specific inhibitors, activation of p38 and JNK was shown to play an important role in CML-collagen-induced activation of FOXO1 and caspase-3. Moreover, inhibition of p38 and JNK reduced CML-collagen-stimulated apoptosis by 48 and 57%, respectively, and by 89% when used together ( P < 0.05). In contrast, inhibition of the phosphatidylinositol 3-kinase/Akt pathway enhanced FOXO1 activation. p38 and JNK stimulation by CML-collagen was almost entirely blocked when formation of ROS was inhibited and was partially reduced by NO and ceramide inhibitors. These inhibitors also reduced apoptosis to a similar extent. Together these data support a model in which AGE-induced apoptosis involves the formation of ROS, NO, and ceramide and leads to p38 and JNK MAP kinase activation, which in turn induces FOXO1 and caspase-3.
Osteopontin localizes to the nucleus of 293 cells and associates with polo-like kinase-1
Authors: Junaid Asad , Moon Michael C. , Harding Gregory E. J. , Zahradka Peter
Published: September 2006

Osteopontin (OPN) is a secreted phosphoprotein involved in cellular proliferation and associated with tumor progression. Although an intracellular form of OPN has been described, its function remains unknown. In this study, a novel nuclear location for intracellular OPN and a correlation with cell division were demonstrated. OPN distinctly localized to the nucleus in a subset of transiently transfected human embryonic kidney 293 cells. Immunoblotting confirmed the nuclear location of native OPN, and results from immunofluorescence studies suggested an association between nuclear OPN and cell cycle progression. Flow cytometry revealed that nuclear and cellular OPN content rose significantly during the S and G2/M phases, respectively. Treatment of cells with the DNA polymerase inhibitor aphidicolin prevented cell cycling and greatly reduced cellular OPN content. The intracellular location of OPN coincided with polo-like kinase-1 (Plk-1), a member of the polo-like kinase family, which, in part through their regulation of centrosome-related events, are integral to successful cellular mitosis. OPN and Plk-1 were coimmunoprecipitated from nuclear, but not cystoslic, extracts, demonstrating an interaction that is limited to the nucleus, presumably during mitosis. Deletion of the COOH terminus of OPN militated against nuclear localization and Plk-1 interaction. Elevated expression of OPN was also associated with an increase in the number of multinucleate 293 cells, whereas transfection of the COOH-terminal-deleted OPN decreased the percentage of multinucleate cells below basal levels. These findings implicate intranuclear OPN as a participant in the process of cell duplication.
Coexistence of Muscarinic Long-Term Depression With Electrically Induced Long-Term Potentiation and Depression at CA3–CA1 Synapses
Authors: McCutchen Eve , Scheiderer Cary L. , Dobrunz Lynn E. , McMahon Lori L.
Published: September 2006

Our laboratory recently characterized a form of long-term depression (LTD) at CA3–CA1 synapses mediated by M1 muscarinic receptors (mAChRs), termed muscarinic LTD (mLTD). mLTD is both activity and NMDAR dependent, characteristics shared by forms of synaptic plasticity thought to be relevant to learning and memory, including long-term potentiation (LTP) induced by high-frequency stimulation (HFS-LTP) and long-term depression induced by low-frequency stimulation (LFS-LTD). However, it remains unclear whether mLTD can occur sequentially with these electrically induced forms of hippocampal plasticity or whether mLTD might interact with them. The first goal of this study was to examine the interplay of mLTD and HFS-LTP. We report that mLTD expression does not alter subsequent induction of HFS-LTP and, further, at synapses expressing HFS-LTP, mLTD can mediate a novel form of depotentiation. The second goal was to determine whether mLTD would alter LFS-LTD induction and/or expression. Although we show that mLTD is occluded by saturation of LFS-LTD, suggesting mechanistic similarity between these two plasticities, saturation of mLTD does not occlude LFS-LTD. Surprisingly, however, the LFS-LTD that follows cholinergic receptor activation is NMDAR independent, indicating that application of muscarinic agonist induces a change in the induction mechanism required for LFS-LTD. These data demonstrate that mLTD can coexist with electrically induced forms of synaptic plasticity and support the hypothesis that mLTD is one of the mechanisms by which the cholinergic system modulates hippocampal function.
Computational Motor Control: Redundancy and Invariance
Authors: Guigon Emmanuel , Baraduc Pierre , Desmurget Michel
Published: September 2006

The nervous system controls the behavior of complex kinematically redundant biomechanical systems. How it computes appropriate commands to generate movements is unknown. Here we propose a model based on the assumption that the nervous system: 1) processes static (e.g., gravitational) and dynamic (e.g., inertial) forces separately; 2) calculates appropriate dynamic controls to master the dynamic forces and progress toward the goal according to principles of optimal feedback control; 3) uses the size of the dynamic commands (effort) as an optimality criterion; and 4) can specify movement duration from a given level of effort. The model was used to control kinematic chains with 2, 4, and 7 degrees of freedom [planar shoulder/elbow, three-dimensional (3D) shoulder/elbow, 3D shoulder/elbow/wrist] actuated by pairs of antagonist muscles. The muscles were modeled as second-order nonlinear filters and received the dynamics commands as inputs. Simulations showed that the model can quantitatively reproduce characteristic features of pointing and grasping movements in 3D space, i.e., trajectory, velocity profile, and final posture. Furthermore, it accounted for amplitude/duration scaling and kinematic invariance for distance and load. These results suggest that motor control could be explained in terms of a limited set of computational principles.
Motor Deficits in Homozygous and Heterozygous P/Q-Type Calcium Channel Mutants
Authors: Katoh Akira , Jindal Jenelle A. , Raymond Jennifer L.
Published: September 2006

P/Q-type voltage-dependent Ca2+channels (VDCCs) are highly expressed in the cerebellum, and mutations of these channels are associated with disrupted motor function. Several allelic variants of the α1A pore-forming subunit of P/Q-type VDCCs have been described, and mice homozygous for these mutations exhibit gait ataxia, as do α1A knockout mice. Here we report that heterozygous α1A mutants also have a motor phenotype. Mice heterozygous for the leaner and α1A knockout mutations exhibit impaired motor learning in the vestibulo-ocular reflex (VOR), suggesting that subtle disruption of P/Q Ca2+currents is sufficient to disrupt motor function. Basal VOR and optokinetic reflex performance were normal in the heterozygotes but severely impaired in the leaner and α1A knockout homozygotes.
Coincidence and invariant approximation theorems for generalizedf‐nonexpansive multivalued mappings
Authors: Khan A. R. , Akbar F. , Sultana N. , Hussain N.
Published: September 2006

The main purpose of this paper is to prove some new coincidence
and common fixed point theorems for noncommuting generalized
f‐nonexpansive multivalued mappings on non‐starshaped domain in
the framework of a Banach space. As applications, related common
fixed point, invariant approximation, and random coincidence point
results are established. This work provides extension as well as
substantial improvement of several results in the existing
literature.
Explicit decomposition of a rational prime in a cubic field
Authors: Alaca Saban , Spearman Blair K. , Williams Kenneth S.
Published: September 2006

We give the explicit decomposition of the principal ideal 〈p〉 (p prime) in a cubic field.
Inégalité de Markov en plusieurs variables
Authors: Pleśniak Wiesław
Published: September 2006

L′inégalité de Markov joue un rôle important en théorie constructive de fonctions. Dans les deux dernières décennies, on a développé sa théorie multidimensionnelle. Le but de cet article est de présenter le récent progrès de cette belle théorie.Markov′s inequality plays an important role in constructive function theory. For the last twenty years, its multivariate versions have been investigated. The purpose of my survey article is to present a recent progress in this beautiful theory.
Finding linking sets
Authors: Schechter Martin , Tintarev Kyril
Published: September 2006

We present the most general definition of the linking of sets in a
Banach space and discuss necessary and sufficient conditions for
sets to link.
On sensible fuzzy ideals of BCK‐algebras with respect toa t‐conorm
Authors: Akram M. , Zhan Jianming
Published: September 2006

We introduce the notion of sensible fuzzy ideals of BCK‐algebras
with respect to a t‐conorm and investigate some of their
properties. We give the conditions for a sensible fuzzy subalgebra
with respect to a t‐conorm to be a sensible fuzzy ideal with
respect to a t‐conorm. Some properties of the direct product and
S
‐product of fuzzy ideals of BCK‐algebras with respect to a
t‐conorm are also discussed.
The decomposition method for linear, one‐dimensional,time‐dependent partial differential equations
Authors: Lesnic D.
Published: September 2006

The analytical solutions for linear, one‐dimensional,
time‐dependent partial differential equations subject
to initial or lateral boundary conditions are reviewed and
obtained in the form of convergent Adomian decomposition power
series with easily computable components. The efficiency and power
of the technique are shown for wide classes of equations of
mathematical physics.
Leray‐Schauder results for multivalued nonlinear contractionsdefined on closed subsets of a Fréchet space
Authors: Agarwal Ravi P. , O′Regan Donal
Published: September 2006

New Leray‐Schauder results are presented for multivalued
contractions defined on subsets of a Fréchet space E. The proof relies on fixed point results in Banach spaces and on
viewing E as the projective limit of a sequence of Banach
spaces.
Laguerre‐type Bell polynomials
Authors: Natalini P. , Ricci P. E.
Published: September 2006

We develop an extension of the classical Bell polynomials
introducing the Laguerre‐type version of this well‐known
mathematical tool. The Laguerre‐type Bell polynomials are useful
in order to compute the nth Laguerre‐type derivatives of a
composite function. Incidentally, we generalize a result
considered by L. Carlitz in order to obtain explicit relationships
between Bessel functions and generalized hypergeometric functions.
Least squares approximations of power series
Authors: Guyker James
Published: September 2006

The classical least squares solutions in C[−1, 1] in terms of linear combinations of ultraspherical polynomials are extended in
order to estimate power series on (−1, 1). Approximate rates of
uniform and pointwise convergence are obtained, which correspond to
recent results of U. Luther and G. Mastroianni on Fourier
projections with respect to Jacobi polynomials.
Modular relations and explicit values of Ramanujan‐Selbergcontinued fractions
Authors: Baruah Nayandeep Deka , Saikia Nipen
Published: September 2006

By employing a method of parameterizations for Ramanujan′s
theta‐functions, we find several modular relations and explicit
values of the Ramanujan‐Selberg continued fractions.
Mappings which preserve regular dodecahedrons
Authors: Kim Byungbae
Published: September 2006

We prove that if a one‐to‐one mapping f : ℝ3 → ℝ3 preserves regular dodecahedrons, then f is a linear isometry up to translation.
The convergence of an implicit mean value iteration
Authors: Rhoades B. E. , Şoltuz Ştefan M.
Published: September 2006

We show the convergence of an implicit mean value iteration when applied to uniformly pseudocontractive maps. Remarks about other implicit mean value iterations are given.
Weakly induced modifications of I‐fuzzy topologies
Authors: Yue Yueli , Fang Jinming
Published: September 2006

The aim of this paper is to study weakly induced I‐fuzzy topological spaces and weakly induced modifications of I‐fuzzy topologies. We give two kinds of weakly induced I‐fuzzy topologies for each I‐fuzzy topology and prove that I‐WIFTOP is a reflective and coreflective full subcategory of I‐FTOP. We also discuss some relationships between several categories.
Classical orthogonal polynomials and Leverrier‐Faddeev algorithmfor the matrix pencils sE − A
Authors: Hernández Javier , Marcellán Francisco
Published: September 2006

In this contribution we present an extension of the
Leverrier‐Faddeev algorithm for the simultaneous computation of the
determinant and the adjoint matrix B(s) of a pencil sE − A where E is a singular matrix but det⁡(sE − A)≢0. Using a previous result by the authors we express B(s) and det⁡(sE − A) in terms of classical orthogonal polynomials.
Transfers for ramified covering maps in homology and cohomology
Authors: Aguilar Marcelo A. , Prieto Carlos
Published: September 2006

Making use of a modified version, due to McCord, of the Dold‐Thom
construction of ordinary homology, we give a simple topological
definition of a transfer for ramified covering maps in homology
with arbitrary coefficients. The transfer is induced by a suitable
map between topological groups. We also define a new cohomology
transfer which is dual to the homology transfer. This duality
allows us to show that our homology transfer coincides with the
one given by L. Smith. With our definition of the homology
transfer we can give simpler proofs of the properties of the known
transfer and of some new ones. Our transfers can also be defined
in Karoubi′s approach to homology and cohomology. Furthermore, we
show that one can define mixed transfers from other homology or
cohomology theories to the ordinary ones.
Auxiliary principle for generalized nonlinear variational‐likeinequalities
Authors: Liu Zeqing , Gao Haiyan , Kang Shin Min , Shim Soo Hak
Published: September 2006

We introduce and study a new class of generalized nonlinear
variational‐like inequalities and prove an existence theorem of
solutions for this kind of generalized nonlinear variational‐like
inequalities. By using the auxiliary principle technique, we
construct a new iterative scheme for solving the class of the
generalized nonlinear variational‐like inequalities. The
convergence of the sequence generated by the iterative algorithm
is also discussed. Our results extend and unify the corresponding
results due to Ding, Liu, Ume, Kang, Yao, and others.
Hypoxia-Induced Pulmonary Vascular Remodeling
Authors: Stenmark Kurt R. , Fagan Karen A. , Frid Maria G.
Published: September 2006

Chronic hypoxic exposure induces changes in the structure of pulmonary arteries, as well as in the biochemical and functional phenotypes of each of the vascular cell types, from the hilum of the lung to the most peripheral vessels in the alveolar wall. The magnitude and the specific profile of the changes depend on the species, sex, and the developmental stage at which the exposure to hypoxia occurred. Further, hypoxia-induced changes are site specific, such that the remodeling process in the large vessels differs from that in the smallest vessels. The cellular and molecular mechanisms vary and depend on the cellular composition of vessels at particular sites along the longitudinal axis of the pulmonary vasculature, as well as on local environmental factors. Each of the resident vascular cell types (ie, endothelial, smooth muscle, adventitial fibroblast) undergo site- and time-dependent alterations in proliferation, matrix protein production, expression of growth factors, cytokines, and receptors, and each resident cell type plays a specific role in the overall remodeling response. In addition, hypoxic exposure induces an inflammatory response within the vessel wall, and the recruited circulating progenitor cells contribute significantly to the structural remodeling and persistent vasoconstriction of the pulmonary circulation. The possibility exists that the lung or lung vessels also contain resident progenitor cells that participate in the remodeling process. Thus the hypoxia-induced remodeling of the pulmonary circulation is a highly complex process where numerous interactive events must be taken into account as we search for newer, more effective therapeutic interventions. This review provides perspectives on each of the aforementioned areas.