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This study aimed to investigate the effects of percutaneous acupuncture stimulation on the viscoelasticity of human tendon structures during isometric contraction. Nine healthy men participated. The experimental order was pre-test, acupuncture stimulation, and post-test. Real and sham acupuncture applications were used at the stimulus site of the medial gastrocnemius muscle (MG), and a crossover trial was performed on the same subjects at a later date. Before and after acupuncture stimulation, tendon elongation and MG aponeurosis were directly measured by ultrasonography while the subjects performed isometric plantar flexions up to the maximum voluntary contraction (MVC) followed by relaxation. The relationship between the estimated MG muscle force (Fm) and tendon elongation (L) during the ascending phase was fitted to a linear regression, the slope of which was defined as the stiffness of the tendon structures. Additionally, the ratio (%) of the area within the Fm–L loop to the area under the curve during contraction and relaxation was calculated and defined as hysteresis. Stiffness rate of change (RC) in real and sham acupuncture was 137.5 ± 116.5% and 55.0 ± 10.4%, respectively (p

We have studied the properties of photoluminescence (PL) from individual isoelectronic traps formed by nitrogen-nitrogen (NN) pairs in nitrogen atomic-layer doped (ALD) GaAs. Micro-PL measurements were performed to investigate the properties of single photons generated from individual isoelectronic traps. Twin PL peaks were observed from individual isoelectronic traps in nitrogen ALD GaAs (001). The PL transitions at longer and shorter wavelength sides were linearly polarized in the [110] and [1-10] directions, respectively. The peak splitting and polarization properties can be explained by some in-plane anisotropy most likely due to strain in host crystal. From individual isoelectronic traps in nitrogen ALD GaAs (111), a single PL peak with random polarization was observed, showing that the growth on (111) surface is an effective way to obtain unpolarized single photons. As for nitrogen ALD GaAs (110), different polarization properties were obtained depending on the atomic configuration of NN pairs. In addition, we have used AlGaAs layers to diminish the in-plane anisotropy and could successfully obtained single emission lines with unpolarized character. Introducing AlGaAs layers was also useful for improving the luminescence efficiency.

The effect of the alkyl side chain on the chiroptical properties of optically active poly(4-(2-hydroxyalkoxyl)phenylacetylene) (poly(1) and poly(2)) and poly(4-(1-hydroxyalkyl)phenylacetylene) (poly(3), poly((S)-4), and poly((R)-4)) films was examined. Poly(1) film showed a reversible color change between yellow and red along with change of circular dichroism (CD) by exposure to solvent vapor and/or by heating, while red poly(2) that had a longer alkoxyl group was not color-changeable. Poly(3) and poly(4) films showed the reversible inversion of the CD spectra, which was completed within several minutes, by exposure to organic solvent vapor and by heating. The CD inversion at lower temperature was observed for poly((S)-4) and poly((R)-4) with a longer alkyl chain. Lyotropic liquid crystalline poly((S)-4) and poly((R)-4) exhibited the highly induced CD and helical fibril structures in the film by selecting the casting solvent, indicating the formation of a predominantly chiral organization.

Optically active poly(diphenylacetylene) derivatives, poly(4-((S)-2-methoxyoctyloxy)diphenylacetylene) (poly-1), poly(4-((S)-2-triethylsiloxyoctyloxy)diphenylacetylene) (poly-2), and poly(4-((S)-2-...

Chiral polyethyne derivatives with lyotropic liquid-crystalline properties are found to be able to self-assemble, forming two chiral organizations with opposite handedness in solid thin films by selection of the casting solvent and its concentration. After the film preparation, chiral organization could also be induced by simple exposure to an appropriate organic solvent's vapor for several minutes without thermal treatment. Furthermore, irreversible inversion of the handedness of the chiral organization in the film could be achieved by exposure to solvent vapor.

In the pursuing of optically active polymers synthesized from N-substituted maleimides (RMIs) for the application on optical resolution of racemates by being used as chiral stationary phase (CSP) of high performance liquid chromatography (HPLC), poly((R)-N-maleoyl-D-phenylglycine alkyl ester)s (poly((R)-RPGMI)s) were obtained by asymmetric anionic polymerizatons of two kinds of (R)-RPGMIs with organometal or organometal/chiral ligand complex as initiators. Chiroptical properties and structures of the polymers obtained were investigated by GPC, CD, XRD and NMR measurements. Among these two kinds of polymers, poly((R)-N-maleoyl-D-phenylglycine methyl ester) (poly((R)-MPGMI)) showed excellent optical resolution ability to many racemates because of its high optical activity attributed to the stereoregular threo-diisotactic structure in the main chain of the polymer.

Fumaramate bearing a phosphoryl choline group, isopropyl-2-[2′-(trimethylammonium) ethyl phosphoryl] ethyl fumaramate (IPTPFA), was radically copolymerized with 2-hydroxyethylmethacrylate (HEMA) in the presence of various crosslinking agents, water, and 2,2′-azobis(isobutyronitrile) to obtain hydrogel membranes. The obtained hydrogel membranes adsorbed bovine serum albumin (BSA) much less than those of poly(HEMA), and the values of water content (H) were higher than those of poly(HEMA). The values of tensile strength and tensile elongation of the hydrogel were 68.4 g/mm2 and 239%, respectively. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2552–2557, 2004

We have studied photoluminescence (PL) observed from single isoelectronic traps formed by nitrogen pairs in nitrogen δ-doped GaAs layers grown on GaAs(1 1 1)A substrates. The PL was composed of a single peak with a narrow linewidth of ∼80 μeV. Polarized PL measurements confirmed that the emission from single isoelectronic traps in nitrogen δ-doped GaAs(1 1 1) is unpolarized irrespective of nitrogen pair arrangements. These results can be explained by in-plane isotropy of the samples, which is consistent with the symmetrical property of GaAs(1 1 1), and demonstrate that utilizing (1 1 1) substrate is an effective means for obtaining unpolarized single photons, which are desirable for the application to quantum cryptography.

A solid-type piezoelectric actuator generates a large force, but the generated displacement is significantly small. In particular, the actuator has a large hysteresis between a control voltage and the control displacement. Hence the application of the actuator has been limited to some special areas. This paper presents a linear piezoelectric actuator without hysteresis. The actuator presented has linearization control circuits and a displacement enlargement mechanism made of elastic hinges, so that the generated displacement is in the range of displacements required for vibration control of machines. To control the actuator, a displacement sensor is used in general, but one of the ends of the sensor must be fixed to a wall. This implies that the application of the actuator is limited. Hence in this paper, an acceleration sensor is used instead of the displacement sensor. This enables us to use the actuator as a conventional linear actuator. Theoretical analysis was given, then experimental tests were carried out to validate the method and the analysis.

We have studied photoluminescence (PL) from individual isoelectronic traps formed by nitrogen-nitrogen (NN) pairs in GaAs. Sharp emission lines due to exciton and biexciton were observed from individual isoelectronic traps in nitrogen atomic-layer doped (ALD) GaAs. The binding energy of biexciton bound to individual isoelectronic traps was approximately 8 meV. Both the exciton and biexciton luminescence lines show completely random polarization and no fine-structure splitting. These results are desirable to the application to the quantum cryptography used in the field of quantum information technology.

A vibration-control mechanism for beams and columns was presented in our previous report in which the earthquake force was transformed into a vibration-control force by using a gear train mechanism. In our previous report, however, only the principle of transforming the earthquake force into the control force was presented; the discussion for real structures and the design method were not presented. The present article provides a theoretical analysis of the column which is used in multi-layered buildings. Experimental tests were carried out for a model of multi-layered buildings in the frequency range of a principal earthquake wave. Theoretical results are compared to the experimental data. The optimal design of the control mechanism, which is of importance in the column design, is presented. Numerical calculations are carried out for the optimal design. It is shown that vibrations of the column involving the mechanism are suppressed remarkably. The optimal design method and the analytical results are applicable to the design of the column.

We report on the observation of biexciton luminescence from single isoelectronic traps formed by nitrogen–nitrogen pairs in nitrogen δ-doped GaAs. The biexciton luminescence intensity showed a quadratic dependence on the excitation power while the exciton luminescence intensity increased linearly with increasing excitation power. The biexciton binding energy was found to be 8 meV, which is considerably larger than that reported for single InAs quantum dots in GaAs. We have also found that both the biexciton and exciton emission lines show completely unpolarized and no fine-structure splitting. This is suitable for the application to polarization-entangled photon pairs.

In this paper, a new method of calibrating adaptive writing pulses suitable for installing into the digital versatile disc random access memory (DVD-RAM) 4.7 GB drive is described. To obtain a wider margin of write/read operation, it is desirable to optimize all adaptive parameters for every disk inserted into the drive. We propose the jitter minimizing (JM) method, which is characterized by using selected test patterns, detecting only jitter in the drive and applying a search algorithm to obtain bottom jitter. As a result of optimizing all parameters by JM, the total calibration time is 4.8 s with the accuracy of ≤1 ns, and overwrite jitter of random data is 8.6% at the drive. It is proved that JM offers the same results as the measurement by the time interval analyzer (TIA), uses small-sized hardware and exhibits satisfactory performance for application in commercial drives.

To test the scavenging of reactive oxygen species (ROS), we added synovial fluids from patients with rheumatoid arthritis (RA) and osteoarthritis, as well as hyaluronic acid (HA) and its 2 subcomponents, D-glucuronic acid and N-acetyl-D-glucosamine, to 2 ROS-generating systems, activated neutrophils and xanthine-xanthine oxidase. Synovial fluid from RA patients, HA, and D-glucuronic acid markedly decreased the O2-, H2O2, OH., and chemiluminescence measured in both systems. HA and synovial fluid, which are known to be susceptible to degradation by excessive ROS in RA patients, also seem to play an active role in protecting articular tissues from oxidative damage.

In the present study, we investigated the possibility that oxidative stress to human peripheral blood monocytes and polymorphonuclear leukocytes (PMNs) can induce interleukin 1 (IL-1)-like activity. Oxidative stress that we used was superoxide anion ( O 2 − > ) and hydrogen peroxide (H2O2). O 2 − , but not H2O2, could induce an IL-1-like factor(s) from monocytes and PMNs. IL-1-like activity from monocytes and PMNs induced by O 2 − > was due to de novo synthesis because no IL-1-like activity was found in culture supernatants and in the lysate of unstimulated cells. We next examined the effects of radical scavengers on production of an IL-1-like factor(s). Generation of IL-1-like activity from monocytes was amplified by preincubation with catalase (H2O2 scavenger), although it was suppressed by preincubation with either superoxide dismutase ( O 2 − > scavenger) or vitamin E (antioxidant analogs). These results suggest that production of an IL-1-like factor(s) from monocytes and PMNs was due to O 2 − > stimulation. Our data that production of an IL-1-like factor(s) from inflammatory cells by stimulation with O 2 − > imply a model of the up-regulation mechanism of inflammation mediated by enhanced IL-1-like factor production stimulated with reactive oxygen species.

To study the mechanisms that regulate the activity of interleukin 2 (IL 2) and possibly limit its activity, we have examined normal human serum for its ability to inhibit IL 2-mediated proliferation of a cloned IL 2-dependent cytotoxic T lymphocyte line (CTLL). Normal human serum contains a factor capable of inhibiting IL 2 dependent proliferation of CTLL cells. This factor is absorbed with the cells but not IL 2 molecules. The inhibitor is heat-labile and inactivated by trypsin treatment. The molecular weight of the inhibitor is 70,000––220,000. The imbalance of the inhibitor is observed in serum from patients with autoimmune disease including systemic lupus erythematosus and rheumatoid arthritis. These results suggest that the serum IL 2 inhibitor may play an important role in the in vivo regulatory mechanism of IL 2 activity and in aberrant immune functions in humans.

The kinetics, at room temperature, of the oxidation of cyclohexene in the presence of benzaldehyde have been measured, and the nature of the products when this oxidation was performed at 70 and 110 °C has been studied. The results indicate that the attack of benzoyl peroxy radical on the double bond of cyclohexene retards the rate of oxygen absorption and also causes epoxidation of cyclohexene. The epoxidation of cyclohexene by peroxybenzoic acid (produced from aldehyde) seems to proceed simultaneously with the epoxidation by peroxy radicals during the oxidation of cyclohexene in the presence of benzaldehyde.