Under the assumption that two coupled neural oscillators control the coordinated finger tapping with both hands, dynamical behavior of this coupled system at steady state was analysed using phase transition curves plotted from measurements taken of the right hand and left hand finger tappings.
From these results, it was shown that the synchronous rhythm pattern and the alternate rhythm pattern were very stable rhythm patterns. These results exactly coincided with psychological experiment data.

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We have no regulatory measures for electrical safety of highly sophisticated health care facilities, although only one tentative standard of manufacturing medical electrical equipments is, at the moment, been in effect. However, this situation must be overcome to realize a truly safe and reliable modernized medical system. From this point of view, we have developed the measures to describe electrical safety of health care facilities equipped with numbers of class I equipment that are concurrently used, since class I equipment play an important role in these facilities. A formula of defining most effective maintenance period has, also, been deduced.
In this paper, the following items are discussed.
(1) Two regular class I equipments can only be used, where single-fault conditions occur simultaneously under the condition that total patient leakage current shall not exceed the safety limit current.
(2) In connection with the above, it is possible to operate up to ten equipments simultaneously if 10-volt main supply voltage or doubled grounding system is used.
(3) Doubled grounding system and periodical inspection of it can decrease sufficiently the possibility of occurrence of single-fault conditions.
(4) Electrical safety of patient environment against occurrence of single-fault conditions can be classified into the following three cases : (i) 10≥n>5, (ii) 5≥n>2, (iii) n≤2, where n represents the number of engaged equipments.
(5) If we enforce periodical inspection every one week for case (i) and every one month for case (ii), the safety probability of the system can be raised to more than O. 999. As for case (iii), it is always safe against occurrence of single-fault conditions.
(6) The optimally effective period of inspection exists and it is deduced theoretically.3

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The regulatory mechanism of rat estrous cycle is described as a single closed loop mathematica lmodel, which is composed of subsystems synthesized by the state space method. These are the hypothalamus, hypophysis, ovary, descending and ascending hypophyseal portal systems, general circulatory system and clearance system including the liver, kidney and submandibular gland. Each subsystem is first synthesized as an open loop system and then unified into a single closed loop system, which is mathematically and physically different from the conventionally proposed open loop models.
In this study the light is the only one input taken into account for the whole system, which shows its own dynamic characteristics caused by the change in internal state variables and parameters, once their initial values are set. We here consider “eigenvalues” of system matrices, which characterize the dynamics of the main subsystems and are assumed to remain unchanged during the estrous cycle. We can, however, observe drastic change in internal state variables (e. g. hormones) of the whole regulatory system caused by the change in some of the gains of the subsystems with many complicated interaction loops.
Under these assumptions we have attempted to explain the dynamic characteristics of the regulatory mechanism in the normal estrous cycle and pattern change in the form of estrous cycle corresponding to the slight change in parameters. Further we have carried out model experiments by modifying the values of state variables corresponding to the acute change in the hormone concentrations and ovariectomy.

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Statistical Package for Medical Science, called by the acronym of SPMS, is an integrated statistical data analysis system designed especially for medical research. SPMS was elaborated to facilitate a close, multipurpose study of medical data adopting the central design concept that many different statistical operations may be run freely on the data. Once the user enters the raw data into the SPMS data file, a variety of related tasks, e. g., generation of new items, static and dynamic case selections, advanced statistical analyses, storage of computed results like factor scores and so on, can be carried out in any sequence.
Compared with other existing well-known packages such as BMDP, SAS and SPSS, the distinctive features of SPMS are (1) capability of treating three-dimensional data structures, (2) pliable transformation of data structures, (3) flexible data stratifications, (4) continuity, connectivity and repeatability, (5) easy-to-implement user's own coded programs, and (6) easy-to-use control language.
Since the beginning of its development, SPMS has been utilized in a service capacity to store and analyze medical data with various structures collected mostly in Tokyo Metropolitan Hospitals and maternity hospitals. On the basis of these experiences, necessary modifications and extensions have been made so that SPMS might immediately cope with practical requests for medical data analysis.

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Electrical field in the human body was simulated by the finite element method which is being watched with keen interest in the field of the structural and continuum mechanics. From the result of simulation, it was revealed that the potential pattern was influenced more distinctly by the effect of boundary, than that of inhomogeneity.

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The surface-detected myoelectric signal has been used for the purpose of controlling devices like a powered prosthesis. This paper describes an on-line real-time simulation system to evaluate a new method of controlling a multifunctional hand prosthesis. The system employs two computers, and classification, estimation and recognition of EMG signal are performed with minicomputer. The model of the hand prosthesis which is displayed on the monitor TV is controlled with microcomputer. From two or three EMG signals picked up from the most suitable muscles, six amplitude and frequency components are derived, then six voluntary movements are classified with theuse of pattern recognition technique based on the linear discriminant analysis method. With theuse of pattern segmentation technique, sequential control signals are obtained at a minimum of every 10 msec. after first detection and recognition of a limb movement. From the experimental results using healthy adults, recognition rate was above 90%, and nearly 100% was achieved in better cases. The prosthesis model on the monitor TV moved correctly and smoothly. Consequentlythis method proved to be effective for controlling a multifunctional hand prosthesis.

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Under a head restraint condition, cats were trained to gaze on a light emitting diode (LED) positioned in front of them for the purpose of studying visual properties of neurons in an unanaesthetized state.
The LED changes its state sequentially as OFF, ON, and flickering. Tongue pushing actions of a lever are reinforced with liquid reward only when the LED is flickering. The duration of LED ON changes randomly from trial to trial and the duration of flickering is also short. Therefore, cats have few chances of being rewarded unless they gaze on the LED during the ON period.
After preliminary training stages, cats could learn the task in several weeks. The electrooculogram showed that the eyes were fixed during the ON period of the LED.

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