Hand-eye system with three-dimensional vision and microgripper for handling flexible wire

A three-dimensional hand-eye system has been specially developed for handling, forming, and inserting flexible wires in electronic assemblies. The system consists of a vision system capable of measuring three-dimensional positions and a gripper capable of microforce control. The hand-eye system performs its tasks based on visual and force sensor data.The vision system uses a camera, a multiplanar laser light projector, and a video-rate image processor to measure the three-dimensional position of a flexible wire on a complex background. The projector consists of multiplanar light beams and a single-planar light beam and is robot-mountable. The single-planar light is used to simplify the matching of the multiplanar light beams and projection images. This is one of the most important features of our method. The measurement time is within 1.2 s for 20 positions on the wire, which is less than one robot cycle. The measurement accuracy is better than 0.2 mm in the plane for a 100×100 mm scene and is better than 1 mm perpendicular to the plane for a depth of 500 mm.The microgripper has 3-axis sensors capable of detecting three types of forces: grasping, pulling, and pushing. The dynamic range of the grasping force is 0.005 to 0.6 N, enabling high-resolution control. Two piezoelectric actuators are used in the microgripper fingers and a 3-mm stroke is achieved by amplifying the actuator's displacement using a two-stage lever.This system has been used for wire handling in magnetic disk slider manufacture, which is a difficult and delicate task. Measurement, grasping, and upper-stage insertion had a 100 percent success rate using autorecovery, making the hand-eye system feasible. This paper discusses design concepts, the range measurement principle, the system itself, and wire-handling applications.     

Preparation and Characterization of LaxC60 Thin Films Fabricated by Layer-by-Layer Deposition

A modification of physical properties of solid-state C₆₀ when La was doped to C₆₀ thin film as a trivalent metal was examined. the thin film was fabricated by using Layer-by-Layer deposition technique with the multi-sources evaporation system. We found that the C₆₀ film changes its electrical character from the insulator to the semiconductor rapidly upon La doping. the temperature dependence of the electrical conductivity is semiconductive with the activation energy of about 0.3eV.     

Expression of costimulatory molecules, B7-1 and B7-2 on human gastric carcinoma

Costimulation of T cells via B7-1 and B7-2 molecules on a tumor has been shown to be important for eliciting cell-mediated antitumor immunity. We studied the surface expression of B7-1 and B7-2 in 24 cases of gastric carcinoma from the primary locus, 20 cases of metastatic carcinoma from malignant ascites, 20 cases of benign gastric mucosa and 7 gastric carcinoma cell lines by two-color flow cytometry with mAb CD80 and CD86. The B7-1 and B7-2 molecules were expressed by 6 cell lines, and 1 cell line showed the predominant expression of B7-2 but not B7-1. Almost all patients with primary gastric carcinoma and benign gastric mucosa showed high levels of expression of the B7-1 and B7-2, revealing approximately 40%-60% positive cells. However, the percentage of B7-1-positive cells of poorly differentiated primary carcinomas was significantly lower than that of well-differentiated carcinoma and normal mucosa (P < 0.01). Furthermore, all of the metastatic carcinoma cells revealed consistently very low or undetectable levels of expression of the B7-1 molecule, only 8% (mean) of cells being positive, despite showing higher levels of B7-2 expression. Thus, it seems likely that decreased or deleted expression of B7-1 correlates with the grade of tumor differentiation, tumor progression and metastasis. These results suggest that the B7-1 molecule on the gastric carcinoma bearing CD80+CD86+ is abrogated during tumor invasion and/or metastasis, and the tumor finally acquires the CD80-CD86+ phenotype. Consequently, inadequate B7-1 costimulation may contribute to the escape of tumors from destruction by the host's immune system.     

Application of conventional activated carbon loaded with dispersed Pt to PEFC catalyst layer

Improvement of the polymer electrolyte fuel cell (PEFC) requires development of highly active electrodes of low cost to facilitate its widespread use. In the present study, the possibility of applying conventional activated carbon particles loaded with Pt to the electrode catalyst layer was tested because the particles were promising in dispersion of Pt and preparation cost. The catalyst layer was formed from the particles and Nafion® and was supported as a thin film on a rotating glassy carbon disk electrode (GC RDE). Activity for oxygen reduction was evaluated by the hydrodynamic voltammetry in perchloric acid to give a current free of the influence of mass transfer in the solution. Compared with a conventional catalyst layer formed from carbon black loaded with Pt, the new catalyst layer exhibited a significant, approximately 6-fold increase in current in the high potential region corresponding to a 100 mV increase in electrode potential. Activity, however, was retarded in the low potential region. This disadvantage was overcome by mixing a conductive agent into the layer and covering it with another layer containing carbon black loaded with Pt. This double catalyst layer exhibited increased activity across all potential regions, indicating the availability of the activated carbon in the electrodes.     

Understanding the thyrotropin receptor function-structure relationship

The thyrotropin (TSH) receptor (TSHR) is a key protein in the control of thyroid function and a major thyroid autoantigen. Recently, molecular cloning of the receptor has been carried out and we now review the impact of this work on our understanding of the physiology and pathophysiology of the TSHR. Analysis of recombinant TSHR proteins expressed in prokaryotic and eukaryotic systems has indicated that post-translational processing is important for the formation of active receptors. Studies of TSHR glycosylation have shown that a 'mature' form of the receptor containing mainly complex-type sugar residues is principally involved in TSH and TSHR autoantibody (TRAb) binding. In addition, the processing of the TSHR peptide chain into two subunits observed with native TSHR has been confirmed using recombinant TSHR. However, despite considerable efforts in many laboratories, the binding site(s) for TSH and TRAb on the TSHR have not been well characterized as yet and lessons learned from the discovery of naturally occurring amino acid mutations of the TSHR confirm the complexity of the hormone and autoantibody binding sites. Future progress in producing large amounts of pure TSHR as well as monoclonal TRAbs, followed by crystallographic analysis of TSHR-TSH complexes and TSHR-TRAb complexes, should be helpful in providing a better insight into the relationship between TSHR structure and function.     

Bloch line propagation with Co-Pt bit patterns in stripe domainsconfined by grooves

Bloch Line (BL) pair propagation using a field-access scheme has been investigated in the straight pair of stripe domains stabilized around completely etched grooves. Potential wells to define the bit position for the BL pairs were produced by the stray field from Co-Pt thin-film patterns with high coercivity. By applying a series of asymmetric triangular bias pulsed fields, a BL pair was propagated at 500 kHz with a 14% bias field margin. At 1 MHz, however, the bias field margin was only 7%. This reduction was due to the long relaxation time of the domain walls. The drive field margins depended on the orientation of the propagation direction relative to the magnetized direction of the Co-Pt bit patterns. This dependence became small when the in-plane bias field was decreased     

Muscle-specific calpain, p94, responsible for limb girdle muscular dystrophy type 2A, associates with connectin through IS2, a p94-specific sequence

p94, a muscle-specific member of calpain family, is unique in that it undergoes rapid and exhaustive autolysis with a half-life of less than 1 h resulting in its disappearance from muscle. Recently, p94 was shown to be responsible for limb girdle muscular dystrophy type 2A. To elucidate the muscular proteolytic system mediated by p94 and to solve the mystery of its unusually rapid autolysis, we searched for p94-binding proteins by the two-hybrid system. Although calpain small subunit plays a crucial role for regulation of ubiquitous calpains, it did not associate with p94. After a screening of skeletal muscle library, connectin (or titin), a gigantic filamentous protein spanning the M- to Z-lines of muscle sarcomere, was found to bind to p94 through a p94-specific region, IS2. The connectin-insoluble fraction of washed myofibrils contained full-length intact p94, suggesting that connectin regulates p94 activity.     

Comparison of retinal breaks between patients with atopic dermatitis and mentally retarded patients with self-inflicted ocular injury]

We compared the distribution of retinal breaks in retinal detachment between patients with atopic dermatitis (AD) and mentally retarded patients who had self-inflicted ocular injury (MR). The cases of AD were 16 eyes in 14 patients (six males and eight females, ranging in age from 15 to 52 years, mean 24.5) and the cases of MR were 6 eyes in 5 patients (5 males, ranging in age from 14 to 25 years, mean 20.2). There was no corneoscleral laceration in either group. In the patients with AD, 14 (87.5%) of 16 eyes had retinal breaks at the vitreous base, and 21 (87.5%) of 24 retinal breaks in 16 eyes were at the vitreous base. In the patients with MR, five (83.3%) of 6 eyes had retinal breaks at the vitreous base and 6(66.7%) of 9 retinal breaks in 6 eyes were at the vitreous base. In both groups, ciliary epithelial breaks and peripheral retinal tears were frequently observed, suggesting that retinal detachment in AD has a pathophysiology similar to traumatic retinal detachment with repeated ocular contusion (self-inflicted injury).     

Estimation of effective dose from CT examination

Tissue or organ doses related to radiological risk were determined for four different types of CT scanners with a spiral scan function. Dose measurements were performed using a Rando phantom and two types of thermoluminescent dosimeters. The effective doses recommended by the International Commission on Radiological Protection in 1990 were evaluated using the tissue or organ doses determined with the phantom measurement. The resultant effective dose per CT examination ranged from 4.6 to 10.8 mSv for chest examination and from 6.7 to 13.3 mSv for upper abdominal examination. It should be noted that the effective dose from CT examination will be increased by increasing in the frequency of CT examinations and technical development of CT scanners.