Analysis of variable number of tandem repeats of human genome D1S80 locus using capillary electrophoresis with laser-induced fluorescence detector

The conventional method of identifying individuals by DNA in the field of forensic medicine is slab gel electrophoresis, which is time-consuming, labor-intensive, and nonquantitative. Accordingly, the use of capillary electrophoresis with a laser-induced fluorescence detector (CE-LIF), human genome D1S80 locus, a DNA marker which has a variable number of tandem repeats (VNTR) on chromosome 1, was examined to improve DNA analysis for identification. Using an internal standard, fragment size of VNTR was accurately and rapidly determined.     

Multiple primary colorectal and gastric carcinoma in Japan

We investigated the occurrence of multiple primary colorectal and gastric cancer (MPCGC) in 1277 colorectal cancer patients between 1972 and 1996. MPCGC was found in 65 (5.1%). In the 28 synchronous cases, gastric or colorectal cancer was accidentally detected by pre-, intra-, or postoperative examinations. In 23 of the 37 metachronous cases, colorectal cancer developed on average 83 months after the operation for gastric cancer. In the other 14 cases, gastric cancer developed on average 70 months after the operation for colorectal cancer. Therefore, careful pre-, intra-, or postoperative examinations are strongly called for in order to not overlook the presence of colorectal or gastric lesions in MPCGC cases.     

Repetition bend properties of Cu-Cr and Cu-Cr-Sn alloys

Repetition numbers of bending of Cu-0.81 wt% Cr, Cu-0.81 wt% Cr-0.14 wt% Sn and Cu-0.26 wt% Cr-0.10 wt% Sn alloys were investigated. After solution treatment, the first two types of copper alloys have a primary chromium phase; this is not so in the last alloy. The primary chromium phase does not influence the repetition numbers of bending of cold-rolled specimens; the repetition numbers of bending of specimens aged at 723 K for 1.8 × 10³ sec after cold rolling are higher than those of cold-rolled specimens. The cause of this is considered to be a recovery of work-hardening during ageing.     

Quantum renormalization group and excitonic phase transition in a strong magnetic field

The critical behavior of excitonic fluctuations is investigated at low temperatures. The Wilson renormalization group is applied to a generalized free-energy functional of the Landau-Ginzburg-Wilson type, which is derived by coarse-graining a microscopic functional. The quantum mechanical effects give rise to an increase of the effective dimensionality at zero temperature. The values of this increase z are z = 1 for a semiconductor and z = 2 for a semimetal, depending on whether the electronic density of states is zero at the Fermi energy or not, respectively. Quantum-classical crossover phenomena appear at a finite but low temperature. As the phase transition point is approached in a semimetal the critical fluctuations in real space first grow two-dimensionally in the plane perpendicular to the magnetic field and then develop three-dimensionally. It is explicitly shown that the mean field theory breaks down in a semiconductor.Correspondence and reprint requests should be addressed to Tatsuzo Nagai.     

Learning behavior of stochastic automata in the last stage of learning

In this paper, a learning behavior of stochastic automata acting in an unknown random environment is considered. Especially, a learning behavior of stochastic automata in the last stage of learning is investigated. Using the theory of Stochastic Stability and Control [9], it is shown that there exists an upper bound of the probability with which stochastic automaton goes back to an unfavorable state within some finite time.     

Superplasticity of Fe-Ni alloys

In the two phase alloys which exhibit superplasticity, strain rate sensitivitym, in the relationship σ =Kε ^m, has been known to be strongly dependent on the volume fraction of the second phase. It, however, has not been necessarily confirmed experimentally on various two phase alloys. In this paper we present an experimental evidence showing that the largestm is obtained when the volume fraction of the second phase is around 0.5.     

Electrodeposition of high purity manganese from low temperature (∼ −16° C) chloride electrolyte

Electrolytic manganese (99-98% purity and sulphur) is commercially produced by using sulphate electrolyte at 35° C with the addition of sulphur compounds at current efficiencies of about 60–65%. In the present investigations, adherent, compact and higher purity manganese was obtained by electrolysis in manganese chloride solutions at lower temperature (–16° C) without any additives such as sulphur or selenium compounds. A basic study was made to determine the current efficiency of deposition from low temperature chloride electrolytes. Factors affecting the process were: bath temperature, current density, ammonium salt concentration, pH and time of deposition. It was concluded that the electrodeposition of high purity manganese from low temperature chloride electrolyte was feasible. From a comparison between the MnCl₂-NH₄SO₃NH₂ and MnCl₂-NH₄Cl systems adopted, it was shown that the former had the advantage over the latter in its higher current efficiency (87% against 84%) below –8° C, while the latter was superior to the former with regard to its wider range of optimum current density (1–4 A dm^–2). The process may be used with advantage when high purity and ductile manganese free of impurities such as sulphur is required and when cooling of the bath is not an important and economic consideration.     

High-performance genetic analysis on microfabricated capillary array electrophoresis plastic chips fabricated by injection molding

We have developed a novel technique for mass production of microfabricated capillary array electrophoresis (mu-CAE) plastic chips for high-speed, high-throughput genetic analysis. The mu-CAE chips, containing 10 individual separation channels of 50-microm width, 50-microm depth, and a 100-microm lane-to-lane spacing at the detection region and a sacrificial channel network, were fabricated on a poly(methyl methacrylate) substrate by injection molding and then bonded manually using a pressure-sensitive sealing tape within several seconds at room temperature. The conditions for injection molding and bonding were carefully characterized to yield mu-CAE chips with well-defined channel and injection structures. A CCD camera equipped with an image intensifier was used to monitor simultaneously the separation in a 10-channel array with laser-induced fluorescence detection. High-performance electrophoretic separations of phiX174 HaeIII DNA restriction fragments and PCR products related to the human beta-globin gene and SP-B gene (the surfactant protein B) have been demonstrated on mu-CAE plastic chips using a methylcellulose sieving matrix in individual channels. The current work demonstrated greatly simplified the fabrication process as well as a detection scheme for mu-CAE chips and will bring the low-cost mass production and application of mu-CAE plastic chips for genetic analysis.