Relationship between perceived softness of bilayered skin models and their mechanical properties measured with a dual‐sensor probe

The development of a sensor system that can predict the subjective softness of human skin is an important goal for the cosmetics industry. Here, we first carried out a subjective softness evaluation test using 65 skin models consisting of polyurethane bilayers with different thickness of the superficial layer and different degree of cross‐polymerization of the basal layer. The results showed that perceived softness was dependent on the mechanical properties of both the superficial and basal layers. Then, we used a recently developed tactile sensor system composed of a piezoelectric tactile sensor and a load cell to measure mechanical softness parameters of the superficial layer and the whole model, respectively. Statistical analysis showed that the data obtained from these two sensors were well correlated with the perceived softness of the prepared models. These results suggest that it may be feasible to predict the subjective softness of human skin in vivo from non‐invasive mechanical softness measurements of the superficial skin layer and whole skin obtained with our new dual‐probe sensor system.     

Basic study of dropout by phase jump characteristic modeling of distributed generators in secondary system for trunk transmission system analysis

The secondary systems are expressed by a reduced model in trunk transmission system analysis. Thus, multiple distributed generators in the secondary system are expressed by the reduced model. But by representing distributed generators by the reduced model, partial dropout of distributed generators cannot be expressed, and therefore there is a possibility that we cannot perform an accurate analysis. Consequently, we studied a method of dropout characteristics in which distributed generators are expressed by the reduced model. To obtain the dropout characteristic, we performed parameter studies by the detailed model and the reduced model on a secondary system under the same conditions. The parameter study indicated that in the dropout characteristic the remaining voltage in the primary system is correlated with the percentage of induction machines in the secondary system. Thus, we derived a dropout characteristic in which the above two quantities were taken as parameters. To confirm the validity of this dropout characteristic, we calculated the dropout magnitudes of the distributed generator for two or more conditions with both the detailed model and the reduced model. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 172(1): 27–37, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20869     

A Flash Photolysis Instrument With Digital Smoothing of Data Using a Fast Fourier Transform

ABSTRACT

Laser flash photolysis is a useful technique for disruption of photolabile chemical bonds. The kinetics of the subsequent reformation of such bonds can then be monitored with a suitable detection system. This technique has proven useful for following the reassociation kinetics of hemeproteins with carbon monoxide. We describe the construction of this apparatus using readily available components, along with microcomputer based signal acquisition and digital filtering of data using a fast Fourier transform. The application of this apparatus to measurement of the association of cytochrome P450 with carbon monoxide is described.     

17beta-Estradiol inhibits the voltage-dependent L-type Ca2+ currents in aortic smooth muscle cells

To elucidate the mechanisms of estrogens-induced relaxation effects on vascular smooth muscle cells, the effects of estrogens and the related hormones were examined in cultured rat thoracic aortic smooth muscle cell lines (A7r5), using the whole-cell voltage clamp technique. The patch pipette was filled with 140 mM CsCl- or KCl-containing internal solution. With CsCl-internal solution, 17beta-estradiol and synthetic estrogens, ethynylestradiol and diethylstilbestrol (0.1-30 mu M) inhibited the Ba2+ inward current (IBa) through the voltage-dependent L-type Ca2+ channel in a concentration-dependent and reversible manner. The potency of the inhibitory effects on IBa was 17beta-estradiol < ethynylestradiol < diethylstilbestrol. 17beta-Estradiol (10 mu M) appeared to reduce the maximal conductance of IBa with only a slight shift of voltage-dependency of inactivation and to affect IBa in a use-independent fashion. On the other hand, testosterone and progesterone (30 mu M) failed to affect IBa. At a holding potential of -40 mV, both vasopressin and endothelin-1 (100 nM) activated a long-lasting inward current. After endothelin-1 (100 nM) activated the current, the additional application of vasopressin (100 nM) could not induce it furthermore, suggesting that each agonist activates the same population of the channels. The reversal potential of the current was about 0 mV and was not significantly altered by replacement of [Cl-]i or [Cl-]0 and the inward current was also observed even when extracellular cations are Ca2+, proposing that it was a Ca2+-permeable non-selective cation channel (IN.S.). La3+ or Cd2+ (1 nM) completely abolished IN.S., however, nifedipine (10 mu M) failed to inhibit it at all. Diethylstilbestrol (1-30 mu M) suppressed the IN.S. evoked by both endothelin-1 and vasopressin in a concentration-dependent manner, while 17beta-estradiol, ethynylestradiol, progesterone and testosterone (30 mu M) failed to inhibit it significantly. In addition, at a holding potential of +0 mV, 17beta-estradiol by itself did not affect the holding currents, and did not inhibit K+ currents evoked by endothelin-1 or vasopressin, possibly due to the Ca2+ release from the storage sites. These results suggest that 17beta-estradiol may play a role in regulating vascular tone, selectively by inhibiting the voltage-dependent L-type Ca2+ current in vascular smooth muscle cells.     

Hepatocyte growth factor activator: a possible regulator of morphogenesis during fetal development of the rat gastrointestinal tract

PURPOSE: Cryosurgical ablation of the prostate is a novel therapeutic modality that induces cell lysis in the prostate by direct application of low temperatures. We have been conducting an ongoing prospective pilot study of the use of cryosurgical prostate ablation in treating patients with nonmetastatic prostate adenocarcinoma since January 1993. Results in 145 consecutive patients with mean 36 months and minimum 12 months of followup are presented. MATERIALS AND METHODS: Accrual was open to patients with clinical stages T1a to T3c prostate adenocarcinoma. Pelvic lymph node dissections were recommended but not required for patients with prostate specific antigen (PSA) greater than 15 ng./ml. before study entry. PSA changes, random prostate biopsy findings and morbidities after cryosurgical prostate ablation were recorded for each patient. RESULTS: Overall actuarial rates at 42 months for maintaining PSA less than 0.3 and less than 1.0 were 59% and 66%, respectively. The overall actuarial progression-free rate at 60 months was 56%. Among 160 biopsies performed 16% showed some evidence of residual carcinoma. Overall crude rates of maintaining either a negative biopsy or PSA less than 0.3 at 6 and 24 months after cryosurgical prostate ablation were 87% and 73%, respectively. Significantly higher morbidities were seen in previously radiated patients undergoing cryosurgical prostate ablation compared to those with no prior radiation. Among nonradiated patients 85% experienced no significant morbidity after cryosurgical prostate ablation. CONCLUSIONS: Although preliminary, short-term outcomes after cryosurgical prostate ablation appear to be comparable to identical outcomes reported for external beam radiotherapy. Based on these results cryosurgical prostate ablation appears to be an effective therapeutic alternative for treating patients with localized prostate adenocarcinoma.     

Thermal degradation behaviour of montmorillonite-α-naphthylamine complex under nitrogen

A thin film of montmorillonite--naphthylamine complex (MNC) was prepared, and then subjected to -ray radiation and heating to 473 K for polymerization of the inserted naphthylamine. MNC was subsequently heated to various temperatures below 1473 K under nitrogen. Montmorillonite film (Mont) was also treated in the same way as the reference sample. Compared with Mont, the MNC-layered structure was remarkably thermally stable and remained so slightly, even after heating to 1273 K. MNC was found to have a homogeneous porous structure after heating to 1273 K. Through comparison with Mont, the thermal degradation behaviour of MNC is discussed on the basis of X-ray diffraction, FT-IR, TG-DTA, elemental analysis, mass spectrum and SEM observations.     

Oxidation resistivity of montmorillonite-α-naphthylamine complex heated under nitrogen

A thin film of montmorillonite--naphthylamine complex (MNC) was heated to various temperatures below 1473 K for 5 min under nitrogen. The resulting samples were further heated to 1073 to 1473 K for 30 min or 5 h in air to examine their oxidation resistivities. A thin montmorillonite film was also treated in the same manner for reference purposes. The layered structure of MNC was retained up to 1273 K under nitrogen, although it changed gradually to an amorphous state with increase in temperature. MNCs after heating below 1073 K under nitrogen were changed to montmorillonite by subsequent heating to 1073 K for 30 min in air, whereas, MNCs heated to 1173 and 1273 K under nitrogen retained somewhat their layered structures, even after heating to 1173 K for 30 min in air. The causes for such differences are discussed on the basis of the results obtained from X-ray diffraction, thermogravimetry, FT-IR and SEM observation.     

SEM study of the fractured surfaces of films and blocks prepared from montmorillonite and its complex with α-naphtylamine

Four samples were heated under nitrogen to determine the relations between heat-treatment conditions and the topographies of the fractured surfaces of the resulting samples. The samples used were thin films (several 10m thick) of lithium-montmorillonite (Mont) and its complex (MNC) with-naphtylamine, and the blocks of raw montmorillonite and its complex with-naphtylamine (MNC). Two characteristic topographies were obtained from MNC film. They were of a very dense structure with the memory of a layered structure after heating to about 1173 K at 1 or 5 K min^–1, and a homogeneous fine porous structure after heating to 1173 to 1273 K at 40 K min^–1. An unique porous structure was also obtained from MNC block, several millimetres thick by heating to 873 K for 1H. However, Mont, in both film and block, was not suitable for preparation of the homogeneous structure, regardless of porous or dense structures.