Reversible Control of Exo‐ and Endo‐Budding Transitions in a Photosensitive Lipid Membrane

We have developed a method for the photomanipulation of lipid membrane morphology in which the shape of a vesicle can be switched by light through the use of a synthetic photosensitive amphiphile containing an azobenzene unit (KAON12). We prepared cell‐sized liposomes from KAON12 and 1,2‐dioleoyl‐sn‐glycero‐3‐phosphocholine (DOPC) and conducted real‐time observations of vesicular transformation in the photosensitive liposome by phase‐contrast microscopy. Budding transitions—either budding toward the centre of the liposome (endo‐bud) or budding out of the liposome (exo‐bud)—could be controlled by light. We discuss the mechanism of this transformation in terms of the change in the effective membrane surface area due to photoisomerization of the constituent molecules.     

Theoretical Investigation of Lattice Thermal Vibration Effects on Phase Equilibria Within Cluster Variation Method

First-principles phase equilibria calculations often overestimate an order-disorder transition temperature due to the neglect of local lattice distortion effects originated from the mixture of elements of different atomic sizes. The lattice vibration effects introduced through the Debye-Grüneisen theory within the quasi-harmonic approximation has proven to be quite effective in circumventing the inconveniences. With the preferential enhancement of the stability of a disordered phase by introducing the lattice vibration effects, the transition temperature was reduced considerably. In order to gain further insight into the lattice vibration effects, a systematic investigation of the vibrational free energy of the Debye-Grüneisen theory is attempted on the two-dimensional square lattice which constitutes a prototype study prior to the first-principles calculations on realistic alloy systems. A particular focus of the present study is placed on the effects of Debye temperatures of constituent phases on the transition temperature. It is shown that lattice softening by lattice vibration stabilizes the disordered phase by reducing the energy expended to accommodate atoms of different sizes, which is manifested by the reduction of the curvature of the atomic potentials. It is, however, predicted that an opposite case can also take place. When the Debye temperature of an ordered phase is lower than that of the pure metals, the ordered phase is more stabilized and the inclusion of the lattice vibration effects in the free energy raises the resultant transition temperature.     

Sodium dl-α-tocopheryl phosphate inhibits ultraviolet-induced production of reactive nitrogen species in human keratinocytes

The phenomenon of aging can broadly be categorized into photoaging caused by exogenous factors and physiological aging that is caused by endogenous factors. Our goal was to develop a non-invasive way to assess changes taking place inside the skin for each type of aging, photoaging and physiological aging, by using near-infrared diffuse reflectance (NIR-DR) spectroscopy. For the photoaging and physiological aging effects, the outer forearm (sun-exposed) and the inner upper arm (sun-protected) skin areas were studied in eighty-six females from twenty-three to sixty-nine years of age. Measurements were made using NIR-DR and subjected to Principal Component Analysis (PCA); the results suggested the possibility of distinguishing and quantifying both types of aging taking place inside the skin by using the 1670–1820 nm and 2000–2230 nm regions of NIR-DR spectra. In photoaging, structural changes in proteins occur which are reflected in the NIR-DR spectra in the form of a peak shift near 2050 nm that is due to a combination of amide A and amide II. On the other hand, physiological aging is associated with a change in collagen quantity as is reflected in the portion of the NIR-DR spectra assigned to protein. Using NIR-DR and PCA, we discovered the possibility of using a non-invasive method for assessing the degree of photoaging and physiological aging as degeneration and degradation.
Key words:  photoaging, physiological aging, non-invasive, NIR-DR, PCA, peak shift, a combination of amide A and amide II, protein, degeneration, degradation.     

Approach for wide use of diagnostic method for XLPE cables using harmonics in AC loss current

A water tree is one aspect of the degradation of XLPE cables used for underground distribution or transmission lines. We have developed the loss current method using the third harmonic in AC loss current for cable diagnosis. The harmonic components in loss current arise as a result of the nonlinear voltage– current characteristics of water trees. We confirmed that the third harmonic in the AC loss current has good correlation with respect to water tree growth and breakdown strength. After that, we applied this method to the actual 66‐kV XLPE cable lines. Up to now, results on over 130 lines have been obtained. In the case of cable lines terminated at gas‐insulated switchgear (GIS), we have to remove the lightning arrestor (LA) and the potential transformer (PT) from the test circuit. The reason is that we are afraid that each LA and PT disturbs the degradation signal from cable lines. It requires extra time (1 or 2 days) and costs more to remove the LA and PT in GIS from a circuit. In order to achieve easy and reasonable diagnosis, we have developed a new method for cable lines terminated at GIS by utilizing a technique that enables one to cancel the signal of the LA and PT from disturbed signal of the cable lines. We confirmed the effect of the new method through experiments with actual cables. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 165(4): 52–59, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20510     

Synthesis of (CrxV1−x )2O3 fine particles by a laser-induced vapor-phase reaction and their crystal structure

Single-phase crystalline fine particles of (CrxV1–x)2O3 have been synthesized by a vapor-phase explosive reaction of a gas mixture of CrO2Cl2 + VOCl3 + H2 + O2 induced by a single laser pulse. The distribution of particle size was uniform with a mean particle size of 80 nm. Lattice constants of (CrxV1–x)2O3 (x=0–1) were accurately determined by the whole-powder-pattern decomposition (WPPD) method. A sharp increase in the a axis-length and a sharp decrease in the c axis-length of the hexagonal unit cell of the oxide (x=0.03) have been observed. The crystal structures of (CrxV1–x)2O3 (x=0.15, 0.5, 0.7) were studied by Rietveld analysis.     

Fabrication of a submicron patterned electrode using an electrospun single fiber as a shadow-mask

We realize a uniform submicron-gap electrode by using an electrospun single fiber as a shadow-mask. By stretching an electrospun fiber, we can decrease the diameter of the fiber from 2 μm to 564 nm with its standard deviation of 57.7 nm. We place the fiber on the center of a Si/SiO₂ substrate followed by the deposition of a molybdenum trioxide adhesion layer and Au electrode. After removing the fiber from the Si/SiO₂ substrate, the submicron-gap gold electrode is formed. Characterization of the gap with scanning electron microscope revealed that the gap has a good uniformity; the average gap length is 865 nm throughout 2 mm gap width.     

Voluntary settlement and the spirit of independence: Evidence from Japan's "northern frontier."

The authors hypothesized that economically motivated voluntary settlement in the frontier fosters independent agency. While illuminating the historical origin of American individualism, this hypothesis can be most powerfully tested in a region that is embedded in a broader culture of interdependence and yet has undergone a recent history of such settlement. The authors therefore examined residents of Japan's northern island (Hokkaido). Hokkaido was extensively settled by ethnic Japanese beginning in the 1870s and for several decades thereafter. Many of the current residents of Hokkaido are the descendents of the original settlers from this period. As predicted, Japanese socialized and/or immersed in Hokkaido were nearly as likely as European Americans in North America to associate happiness with personal achievement (Study 1), to show a personal dissonance effect wherein self-justification is motivated by a threat to personal self-images (Study 2), and to commit a dispositional bias in causal attribution (Study 3). In contrast, these marker effects of independent agency were largely absent for non-Hokkaido residents in Japan. Implications for theories of cultural change and persistence are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Isolation of MHC class I-restricted tumor antigen peptide and its precursors associated with heat shock proteins hsp70, hsp90, and gp96

We have previously demonstrated that vaccination with heat shock proteins hsp70, hsp90, and gp96 elicits specific immunity against the tumor from which the hsps were purified. Although the association of tumor Ag peptides with these hsps have been suggested, the identification of the peptides or their precursors stripped from the hsps remained to be resolved. We show in this report that an Ld-restricted cytotoxic T lymphocyte epitope of a mouse leukemia RLmale symbol1 and its precursors are associated with the chaperones hsp90 and hsp70 in the cytosol and gp96 in the lumen of the endoplasmic reticulum. Hsp70 was associated with only final sized octamer, while hsp90 was found to associate with the octamer and two distinct precursor peptides. The gp96 was associated with the octamer and one of the two precursors. Thus, each of the hsps bound a distinct set of peptides. Our results have demonstrated for the first time that the hsps associate not only with final sized tumor Ag peptide but also with its precursors. The implication of this evidence is also discussed in terms of the roles of hsps in MHC class I Ag processing/presentation.     

Methanol decomposition to synthesis gas at low temperature over palladium supported on ceria–zirconia solid solutions

The Ce_xZr_1−xO₂ solid solution was used as a support of a palladium catalyst for methanol decomposition to synthesis gas at low temperature. All Pd-containing catalysts tested in this study showed high selectivity to synthesis gas (over 96%). The Pd supported on the composite oxide with a Ce/Zr molar ratio of 4/1 exhibited the highest activity. Pd/Ce_0.8Zr_0.2O₂ (17 wt.%) (cop) (prepared by coprecipitation method) showed a conversion of 51.2% for the methanol decomposition at 473 K, which was higher than those over 17 wt.% Pd/CeO₂ (cop) (40.7%) and 17 wt.% Pd/ZrO₂ (cop) (24.3%) at 473 K. The 17 wt.% Pd/Ce_0.8Zr_0.2O₂ (cop) catalyst showed a higher BET surface area and smaller Pd particles than those of 17 wt.% Pd/CeO₂ (cop). Moreover, a more active Pd^σ+ state could be maintained by Zr⁴⁺ ion modification due to promotion of the oxygen mobility and enhancement of the reductibility and increase in the acid sites of the CeO₂ support. The 17 wt.% Pd/Ce_0.8Zr_0.2O₂ (cop) catalyst showed a much higher conversion (51.2%) than that over 17 wt.% Pd/Ce_0.8Zr_0.2O₂ (imp) (prepared by impregnation method) (17.2%) at 473 K. This is due to the 17 wt.% Pd/Ce_0.8Zr_0.2O₂ (cop) possessing many small Pd particles. The 17 wt.% Pd/Ce_0.8Zr_0.2O₂ (cop) catalyst showed an initial conversion of 51.2% at 473 K but the conversion decreased to 43.1% after 24 h on stream. This deactivation was attributed to carbonaceous deposit on the catalyst surface. The amounts of coke on the 17 wt.% Pd/Ce_0.8Zr_0.2O₂ (cop) catalyst were 0.9 wt.% after 24 h on stream at 473 K and 2.1 wt.% after 1 h on stream at 523 K.