Approximation theorems for operator exponential and cosine functions

An integral approximation error is estimated for an operator exponential function, and the unimprovability of the estimate with respect to order is investigated. The smoothness of the initial vector in terms of the order of accuracy of the Cayley transform method is substantiated for approximations of operator exponential and cosine functions.     

Optical and electrical anisotropies of polydiacetylene derivative film aligned by shear stress

The molecular alignment of polydiacetylene (PDA) derivatives and their optical and electrical properties of thin films based on PDA derivatives have been studied. The PDA derivatives were aligned depending on the direction of applied shear stress in the film. From measurements of the polarized absorption and current–voltage characteristics, the optical and electrical anisotropies have been observed, that was discussed by taking the PDA main chain alignment into consideration.     

Mutations of the transforming growth factor-beta type II receptor gene are strongly related to sporadic proximal colon carcinomas with microsatellite instability

BACKGROUND: Mutations of the transforming growth factor-beta type II receptor gene (TGF-beta RII) have been found in several replication error-positive sporadic colorectal carcinomas and hereditary nonpolyposis colorectal carcinoma cell lines. The aim of this study was to clarify the role of TGF-beta RII in sporadic colorectal carcinogenesis. METHODS: The authors screened for mutations at simple repeated sequences in the TGF-beta RII gene by polymerase chain reaction-single strand conformation polymorphism. They also examined genomic instability, using five microsatellite DNA markers in 69 sporadic colorectal carcinomas. When the carcinomas exhibited the TGF-beta RII mutations, the authors screened further for mutations in two DNA mismatch repair genes, hMSH2 and hMLH1. RESULTS: Seven of the 69 cancers (10%) showed one or two A deletions in TGF-beta RII and resultant frameshift mutations in nucleotide positions 709-718 containing a (A) 10 repeated sequence; but none of these appeared in the corresponding normal DNA, indicating a somatic mutation. All of the seven cancers were located in the proximal colon; there were none in the distal colon (P < 0.01). On the other hand, 22 of the 69 carcinomas (32%) showed the replication error-positive phenotype. The frequency of replication errors in proximal colon carcinomas was higher than that in distal colon carcinomas (P < 0.05). All 7 cancers with TGF-beta RII mutations showed replication errors. One of them revealed a nonsense mutation at codon 413, and 1 revealed a loss of heterozygosity in hMSH2. CONCLUSIONS: These data indicate that mutations of TGF-beta RII are strongly related to proximal colon carcinomas with microsatellite instability and that the mechanism of carcinogenesis in some proximal colon carcinomas is similar to that in hereditary nonpolyposis colorectal carcinoma.     

Broad-band SiGe MMICs for phased-array radar applications

This paper reports the performances of several broad-band monolithic SiGe monolithic microwave integrated circuits (MMICs) suitable for phased-array radar applications. The amplitude and phase control MMIC designs are based on an optimized SiGe p-i-n diode offered by the IBM 5HP SiGe foundry process. Utilizing this diode, several control circuitries including a broad-band (1-20-GHz) monolithic single-pole double-throw switch, a five-port transfer switch, a 6-bit phase shifter, and a 5-bit attenuator, all operating over 7-11 GHz, are designed. Also, the design and performance of an SiGe heterojunction bipolar transistor variable-gain cascode amplifier that combines the functionality of an amplifier and an attenuator into one MMIC is described.     

Immunochemical approaches to AGE-structures: characterization of anti-AGE antibodies

An extractionless method for determining aflatoxin M1 (AFM1), a major metabolite of aflatoxin B1 (AFB1), in human urine was developed. The biological fluid is injected directly into the chromatographic system after simple dilution and centrifugation. A pre-column, packed with a cation-exchange phase and coupled on-line to a column-switching liquid chromatography (LC) system, is used for sample pre-treatment and concentration. The analytes are non-selectively desorbed with the LC eluent and cleaned by means of a column-switching procedure. Pre-treatment and analysis were performed within 40 min. Average AFMI recovery reached 97% in the 10-100 ng/l range of urine. The detection limit of AFM1 in urine and milk was 2.5 ng/l for 1 ml of injected sample. A comparison with an immunoaffinity column clean-up and LC method was performed. The method was applied to determine AFM1 in the urine of AFB1 gavaged rats, and in the urine of both potentially exposed and supposedly unexposed workers. The method was also extended to milk.     

Hand-mirror cells acute lymphoblastic leukemia (L3)

To our knowledge, this report represents the first confirmed case in Japan of a 15-year-old boy with acute lymphoblastic leukemia (ALL).L3 with hand-mirror cells (HMC) in the bone marrow. HMC lymphoid leukemia is an unusual variant of ALL in which the bone marrow lymphoblasts manifest distinctive hand-mirror morphologic features. HMC lymphoblast is characterized by an asymmetric foot-like cytoplasmic process that extends from the portion of the cell, thus giving it the light-microscopic appearance responsible for its name. Besides ALL, HMC has been reported in acute myeloblastic leukemia (AML), blastic crisis of chronic myelogenous leukemia, non-Hodgkin's lymphoma, and infectious mononucleosis. HMC has been reported to be prevalent in ALL.L1 and L2 as compared with L3.     

Development of a MAGLEV superconducting magnet for the Yamanashitest line in Japan: vibration characteristics and analysis for design

A high-performance and high-reliability magnetically levitated (MAGLEV) superconducting magnet (SCM) was developed. Its heat generation per unit time by the electromagnetic forces due to the spatially fifth ripple magnetic fields from levitation coils is under 2 W at the frequency range in which vehicles are levitated. The vibration mode of inner vessels that makes the largest contribution to heat generation in SCMs is clarified, the torsion mode. A modeling method to analyze SCM vibration, which considers the effect of the bogie frames of a vehicle, is examined, and heat generation in SCMs is calculated from the vibration of the inner vessel. Using the numerical analysis method, new SCMs combined with new bogie frames for the Yamanashi Test Line are designed. Good performance in vibration and heat generation of these SCMs is predicted by numerical analysis