Degradation of polyetherurethane by subcutaneous implantation into rats. I. Molecular weight change and surface morphology

The pharmacological characteristics of the 3-oxamethano-prostaglandin I1 compound (+)-methyl [2-[(2R,3aS,4R,5R,6aS)-octahydro-5-hydroxy-4- [(E)-(3S,5S)-3-hydroxy-5-methyl-1-nonenyl]-2-pentalenyl]etho xy] acetate (SM-10902, CAS 139403-31-9), a novel stable analogue of prostacyclin and its free acid, SM-10906, were studied. SM-10902 was rapidly deesterified to its free acid in rabbit and human serum. SM-10902 and SM-10906 exhibited antiplatelet potency against ADP-induced aggregation in rabbit and human platelets. In the presence of diisopropyl fluorophosphate, an esterase inhibitor, the antiplatelet activity of SM-10902 was markedly reduced, to much less than that of SM-10906. SM-10906 inhibited platelet aggregation induced by various inducers in several species and enhanced the cyclic AMP (cAMP) level in human platelets. These activities were nearly equal to those of prostaglandin (PG) E1 and less than those of PGI2. SM-10906 relaxed isolated rabbit mesenteric and bovine coronary arteries, and elevated the cAMP level in bovine coronary arteries. SM-10906 given intravenously exhibited a sustained reduction in blood pressure based on vasodilation in ganglion-blocked, angiotensin II-supported rats. SM-10902 applied to the guinea-pig auricles increased the skin temperature, but SM-10906 and PGI2 showed no such effect. In conclusion, SM-10902, which is considered to be a prodrug of SM-10906, was suggested to exert its anti-platelet and vasodilator activities through the increase of cAMP. Since SM-10902 penetrates well into the skin, it may be useful as an external preparation to improve peripheral circulatory insufficiency.     

Simplified protocol for detection of protein-ligand interactions via surface-enhanced resonance Raman scattering and surface-enhanced fluorescence

A simple and effective protocol for detections of protein-protein and protein-small molecule interactions has been developed. After interactions between proteins and their corresponding ligands, we employed colloidal silver staining for producing active substrates for surface-enhanced Raman scattering (SERS) and surface-enhanced fluorescence (SEF). Tetramethylrhodamine isothiocyanate (TRITC) and Atto610 were used for both Raman and fluorescent probes. We detected interactions between human IgG and TRITC-anti-human IgG, and those between avidin and Atto610-biotin by surface-enhanced resonance Raman scattering (SERRS) and SEF. The detection limits of the proposed SERRS-based method are comparable to those of the proposed SEF-based one, 0.9 pg/mL for anti-human IgG and 0.1 pg/mL for biotin. This protocol exploits several advantages of simplicity over other SERS and SEF-based related methods because of the protein staining-based strategy for silver nanoparticle assembling, high sensitivity from SERRS and SEF, and high stability in photostability comparing to fluorescence-based protein detections. Therefore, the proposed method for detection of protein-ligand interactions has great potential in high-sensitivity and high-throughput chip-based protein function determination.     

Effects of annual fluctuation of environmental factors on starch properties in potato tuber development

To test the effects of the annual fluctuation of the environmental factors on the starch properties in potato tuber development, starches were isolated from potato cultivars grown for ten consecutive years (2001–2010) on the experimental farm in Memuro, Hokkaido, the northernmost island of Japan. The median granule size, phosphorus content, and rapid visco‐analyzer pasting properties, peak viscosity, breakdown, and pasting temperature of these starches were analyzed. Daily temperature and precipitation records in Memuro were obtained from the Japan Meteorological Agency. Moreover, the correlation coefficients of yearly accumulated temperature and precipitation from flowering to harvesting with all the starch quality parameters were calculated. No relationships of accumulated temperature with median granule size, peak viscosity, and breakdown were found. The low phosphorus content was slightly associated with the high accumulated temperature. The pasting temperature was significantly and positively correlated with the accumulated temperature, suggesting that the pasting temperature strongly responds to the environmental temperature during potato tuber development. In contrast, all the starch quality parameters were almost irrespective of the precipitation during potato tuber development.     

SEM observation of wet biological specimens pretreated with room-temperature ionic liquid

A facile pretreatment process for SEM: The use of room temperature ionic liquids (RTILs) provides an interesting method for SEM of biological specimens. We used a novel and concise method of pretreatment, excluding fixation or Au sputtering steps. Fine and smooth-textured SEM images of a wide variety of biological specimens treated in this way were observed without artefacts.     

Multijunction thermal converter with improved frequency characteristics between 10 Hz and 1 MHz

A new multijunction thermal converter (MJTC) for precision AC–DC transfer standard has been developed. A U‐shaped heater pattern was sputter‐deposited onto an AlN plate in order to reduce thermoelectric effect, which causes the frequency‐independent AC–DC transfer difference. Both low‐frequency and high‐frequency characteristics improved as a result of the new configuration, and the AC–DC transfer difference of the MJTC was evaluated to be <1 µV/V between 10 Hz and 100 kHz and <10 µV/V up to 1 MHz. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Homogenized elastic-viscoplastic behavior of plate-fin structures at high temperatures: Numerical analysis and macroscopic constitutive modeling

In this study, homogenized elastic-viscoplastic behavior of an ultra-fine plate-fin structure fabricated for compact heat exchangers is investigated. First, the homogenized behavior is numerically analyzed using a fully implicit mathematical homogenization scheme of periodic elastic-inelastic solids. A power-law creep relation is assumed to represent the viscoplasticity of base metals at high temperatures. The plate-fin structure is thus shown to exhibit significant anisotropy as well as noticeable compressibility in both the elastic and viscoplastic ranges of the homogenized behavior. Second, a non-linear rate-dependent macroscopic constitutive model is developed using the quadratic yield function proposed for anisotropic compressible plasticity. The resulting constitutive model is shown to be successful for simulating the anisotropy, compressibility, and rate dependency in the homogenized behavior in multi-axial stress states.     

Identification of Fuzzy Relations with Multiple Hyperplanes by Genetic Algorithm in Structural Design

Abstract: This paper proposes a method for formulation and quantification of human subjective evaluations and uncertain numerical values by using multiple hyperplanes based on the results of questionnaires distributed to structural designers that are composed of four questions about structural design and planning, i.e., ( Q 1) structural damage , ( Q 2) structural economy in a macroscopic sense , ( Q 3) structural safety, and ( Q 4) opening patterns in facade. In this paper, some hyperplanes in multidimensional spaces are used as a method to identify fuzzy relations (states) in intelligent fuzzy networks for seismic structural planning. A genetic algorithm is employed as a search method for optimal formulations and is proved to be very effective as a method for such an identification.     

Determination of three dimensional in situ stress from core discing based on analysis of principal tensile stress

To determine all of the components of in situ stress from core discing, both the directions and magnitudes of the principal in situ stresses must be determined for a disc of a given thickness. In this study, we analyzed the direction and magnitude of tensile stress below an HQ core stub for 11 core lengths using stress conditions under which core discing is likely to occur. First, based on an analysis of the direction of tensile stress below the core stub, we propose a method for determining directions of in situ stress from the height distribution at the periphery of the end surface of a disc. This method can be used with a disc of any thickness. Next, based on an analysis of the magnitude of tensile stress in the central part of a core, we propose a linear criterion for core discing, which can be applied to a core of any length. This criterion was in good agreement with an empirical formula obtained previously in laboratory experiments. By combining information on the direction of in situ stress and the linear criterion for core discing, we propose a method for determining all of the components of in situ stress from core discing under the assumption that vertical stress is given by the overburden stress. Finally, these methods were applied to discs obtained from a field where hydraulic fracturing was performed to measure horizontal stresses. The results showed that the azimuths of the principal stresses estimated from core discing were consistent with those of the principal horizontal stresses determined by hydraulic fracturing and that while the magnitudes of the principal horizontal stresses estimated from core discing showed a large scatter, they were similar to those determined by hydraulic fracturing.     

FTIR studies of adsorption and photocatalytic decomposition under UV irradiation of dimethyl sulfide on calcium hydroxyapatite

The adsorption and photocatalytic decomposition under UV irradiation of dimethyl sulfide ((CH₃)₂S: DMS) on synthetic colloidal calcium hydroxyapatite (Ca₁₀(PO₄)₆(OH)₂: Hap) particles were examined by in vacuo IR measurements. The adsorption isotherms of DMS on Hap exhibited the Langmuir type. The saturated adsorbed amount of DMS was increased with increasing the outgassing temperature of Hap, showing a maximum of 2.4 molecules/nm² at 250 °C. Similar tendency could be observed for change in area intensity of surface P-OH bands of Hap estimated from in vacuo IR measurements against outgassing temperature. By adsorption of DMS, the surface P-OH bands of Hap weakened while the CH bands due to DMS appeared. These results revealed that the DMS was adsorbed on surface P-OH groups of Hap. When the UV light was irradiated to the DMS-adsorbed Hap, the surface P-OH bands revived and the CH bands weakened. This fact strongly indicated the photocatalytic decomposition of DMS took place on surface P-OH groups of Hap, which was thought to be due to the formation of surface P-OH radicals by UV irradiation.