Combination of genomic DNA fingerprinting into the medaka specific-locus test system for studying environmental germ-line mutagenesis

A proniosome based transdermal drug delivery system of levonorgestrel (LN) was developed and extensively characterized both in vitro and in vivo. The proniosomal structure was liquid crystalline-compact niosomes hybrid which could be converted into niosomes upon hydration. The system was evaluated in vitro for drug loading, rate of hydration (spontaneity), vesicle size, polydispersity, entrapment efficiency and drug diffusion across rat skin. The effect of composition of formulation, amount of drug, type of Spans, alcohols and sonication time on transdermal permeation profile was observed. The stability studies were performed at 4 degrees C and at room temperature. The biological assay for progestational activity included endometrial assay and inhibition with the formation of corpora lutea. The study demonstrated the utility of proniosomal transdermal patch bearing levonorgestrel for effective contraception.     

Role for cingulate motor area cells in voluntary movement selection based on reward

Most natural actions are chosen voluntarily from many possible choices. An action is often chosen based on the reward that it is expected to produce. What kind of cellular activity in which area of the cerebral cortex is involved in selecting an action according to the expected reward value? Results of an analysis in monkeys of cellular activity during the performance of reward-based motor selection and the effects of chemical inactivation are presented. We suggest that cells in the rostral cingulate motor area, one of the higher order motor areas in the cortex, play a part in processing the reward information for motor selection.     

Fretting of glass

Fretting damage to a glass surface in contact with a steel ball was investigated. In the initial stage of fretting, severe wear occurred on the steel ball and considerable wear debris was transferred to the glass surface. The coefficient of friction increased during this stage by 80%. Fatigue cracks were observed on the glass surface under conditions of high normal load and tangential force. The mechanism of fretting fatigue and fretting wear is discussed in relation to a brittle material. Finally the effect of thin metal foil inserts in reducing fretting damage is described.     

Hydrogen analysis of mineral samples at University of Tsukuba

This study reports the present status of our work on the hydrogen analysis of mineral and rock samples. The preparation of a standard material by means of ion implantation, a method of its calibration and the application of the method are described. The number of hydrogen atoms per unit volume in the standard material can be determined from the simultaneous observation of -particles, γ rays and –γ coincidence events for the ¹H(¹⁹F,γ) reaction at the 16.44 MeV resonance energy. The hydrogen content in a natural obsidian determined with the method mentioned above is in agreement with that obtained by FTIR. A heavy-ion microbeam system under construction, which consists of a Russian-type quadrupole magnet for beam focusing, a beam defining slit system and a γ-ray detector, is also described.     

An automatic class generation mechanism by using method integration

The paper presents a mechanism for automatically generating new classes from classes existing in a library by using their modification histories. To generate classes that are likely to meet a programmer's requirements and that are consistent with the existing classes, we propose three actors: a Specifier, a Finder, and an integrator. The Specifier records the history of modifications between methods with the same interface of a parent class and its heir. If the required method is not defined in the existing class which a programmer is referring to, the Finder retrieves classes similar to the referenced class and the Integrator applies the past modifications of similar classes to the referenced class. Classes are determined to be similar, based on their positions in a class hierarchy tree. Both the Specifier and Integrator are achieved by using a method integration algorithm based on object oriented bounded program slicing and class dependence graph matching. This mechanism enables programmers to reuse classes with little or no modification, and thus, easily create object oriented programs     

Ultrashallow junction formation by self-limiting LTP and its application to sub-65-nm node MOSFETs

We have developed a novel laser thermal process that dramatically enhances laser exposure windows by controlling the heating process in a self-limiting way. Key technology is realized by introducing a new process combination of preamorphization implantation and a heat absorber with a phase switch layer, and by optimizing them. The V/sub th/ rolloffs of MOSFETs formed by this method were remarkably improved compared to those by rapid thermal annealing when offset-spacer and halo-implantation processes were not applied. Its effectiveness was also verified in 50-nm gate complementary metal-oxide semiconductor devices for the first time by confirming that the drain current increased with laser fluence beyond the conventional exposure limit.     

InGaAs quantum dots formed in tetrahedral-shaped recesses on GaAs (111)B grown by metalorganic chemical vapor deposition

Novel semiconductor quantum dots (QDs), grown in tetrahedral-shaped recesses (TSRs) formed on a (111)B GaAs substrate, are described from both material science and device application points of view. After explaining the fabrication procedure for TSRs, growth of InGaAs QDs and their optical properties are explained. It is revealed that an InGaAs QD of indium-rich chemical composition is formed spontaneously at the bottom of each TSR. The mechanism of the QD formation is discussed in detail. It is proved from magneto-photoluminescence that the QDs actually have optical properties peculiar to zero-dimensional confinement. Several experimental results indicating excellent growth controllability of the QDs are presented. Finally, recent challenges to apply the QDs to electronic memory devices are reported. Two kinds of devices, where the position of individual QD is artificially controlled, are proposed for the first time and the preliminary experimental results are explained.