Quantitative determination of cardiac glycosides in Digitalis lanata leaves by reversed-phase thin-layer chromatography

We have recently chosen to undertake a comprehensive evaluation of the modulation of gene expression by oxidative stress, using mRNA as a marker. Our model system is HA-1 hamster fibroblasts, using conditions under which we observe an adaptive response. Under these conditions, the HA-1 cells respond to a minimally toxic "pretreatment" dose of hydrogen peroxide by synthesizing RNAs and proteins that protect them against subsequent exposure to a highly cytotoxic concentration of hydrogen peroxide. Using the differential display technique to screen for modulated RNAs, we have recently reported an RNA species, adapt15/gadd7, whose steady-state level is significantly induced by a pretreatment dose of hydrogen peroxide (D. R. Crawford, G. P. Schools, S. L. Salmon, and K. J. A. Davies (1996) Arch. Biochem. Biophys. 325, 256-264). Here we report a second induced mRNA, designated adapt33. Two homologous adapt33 mRNAs were revealed by Northern blot hybridization. Both of these species were inducible by hydrogen peroxide, and they were sized at 1.46 and 0.99 kb. These inductions appeared to be dependent upon calcium, occurred as early as 90 min, and were maximal at 5 h. Cell fractionation revealed that a significant proportion of adapt33 RNA is associated with active translation. adapt33 is a novel sequence, as determined by cloning, sequencing, and GenBank analysis. adapt33 represents a new oxidant-inducible RNA and marker of cellular oxidative stress and a potential aid in the study, detection, and possible therapy of oxidant-related disorders.     

Automatic detection of the topographical distribution of EEG rhythms based on an iterative adjustment of the averaged reference potential

Electroencephalogram (EEG) interpretation is important for the investigation of brain diseases. In this study, an automatic technique was developed to detect the topographical distribution of EEG rhythms. In order to obtain the topographical distribution, the amplitude of the EEG rhythm was analyzed based on the referential derivation where the reference potential was adjusted iteratively. The result of the automatic detection of the topographical distribution was helpful in highlighting the EEG rhythms of interest for automatic EEG interpretation. The technique developed has application significance for real clinics.     

Design of discrete time adaptive PID control systems with parallel feedforward compensator

This paper deals with the design of an adaptive PID control system with a parallel feedforward compensator (PFC) for discrete-time SISO systems and its application to water level control of a 3-tank system. The proposed method utilizes the characteristics of almost strict positive realness (ASPR) of the controlled plant. A conventional design scheme of a PFC which realizes an ASPR augmented controlled plant is also proposed. Further it is shown that the introduction of an internal model improves the control performance of the control system with the PFC. The effectiveness of the proposed method is confirmed through water level control experiments on a three-tank SISO system.     

Bottom-up pyramid cellular acceptors with three-dimensional layers

In 1997, C.R. Dyer and A. Rosenfeld introduced an acceptor on a two-dimensional pattern (or tape), called the pyramid cellular acceptor, and demonstrated that many useful recognition tasks are executed by pyramid cellular acceptors in time proportional to the logarithm of the diameter of the input. They also introduced a bottom-up pyramid cellular acceptor which is a restricted version of the pyramid cellular acceptor, and proposed some interesting open problems of the bottom-up pyramid cellular acceptors. On the other hand, we think that the study of threedimensional automata has been meaningful as the computational model of three-dimensional information processing such as computer vision, robotics, and so forth. In this paper, we investigate about bottom-up pyramid cellular acceptors with three-dimensional layers, and show their some accepting powers. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

Fatigue behaviour of precipitation-hardening medium C steels containing Cu

The presence of Cu precipitates counteracts the cyclic softening present in ordinary quenched and tempered steels. This is expected to result in an increase in fatigue limit. The fatigue crack propagation rate (dc/dN) at constant K in the Cu-C steels was shown to depend on heat-treatment and carbon content. To maximize yield strength and minimize ¦da/dN¦_K for tempering at 500° C, one must choose a low C content and temper for a short time; ¦da/dN¦_K in 0.28 wt % C-1.45 wt % Cu tempered for 13 min was one-third that for 0.45 wt % C-1.45 wt% Cu tempered for 200 min. There is also an advantage in adding Cu while simultaneously lowering the Ccontent. The dc/dN data are discussed in terms of the yield strength and the energy to form a unit area of fatigue crack, U, which was measured using foil strain gauges. The quantity (¦dc/dN ¦_{K y} ² U) where _y is the cyclic yield stress, was found to be nearly constant. In the 0.28 wt % C-1.45wt % Cu alloy, short ageing times at 500° C resulted in greater resistance to initiation of cracks at notches for low Ks than long ageing times.