Language is the most characteristic of complex human functions. In principle, the role of language is to produce a signal with an intended semantic interpretation for establishing human cornmunication. There are different ways of signal transmission in human communication which are inherently controlled by physiological nature and restriction ofl human body. In speech communication, speech sounds are produced by the movements of the articulatory organs under the control of motor commands from the central nervous system and the transformation of discrete codes is made into continuous acoustic signals, which are eventually decoded through the perception system of listeners. The physiological study of dynamic aspects of speech production is thus believed to be one of the most essential approaches for disclosing the nature of language behavior.
In the present paper, several topics are presented with special reference to the physiological nature of the articulatory behavior at the different levels of speech production. Among those, laryngeal adjustments in pitch control and voicing distinction are discussed based on the fiberscopic and electromyographic data. The same techniques are used for describing the velopharyngeal control in oral vs. nasal distinction. Further, preliminary analysis of tongue movements, also presented.
It should be realized that we are still at the stage of preliminary data gathering in the realm of research on language behavior. It is hoped that cooperative work among medical, engineering and linguistic fields will lead us to future progress in understanding of the nature of language.

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The mechanochemical materials are synthetic polymers (polyelectrolytes) which can directly convert chemical energy into mechanical energy like the muscle. Although their microscopic contractile mechanism is apparently different from that of the skeletal muscle, they are most similar in the property to the muscle fiber when it is immersed in sodium solution. They also have similar properties to the skeletal muscle as well as to the muscle fiber, in view of biopolymers; of the form of the energy conversion, and, of the order of the exerted force and mechanical work divided by the weight of the substance.
In this report, experimental results of mechanical behavior of the mechanochemical materials (crosslinked polyacrylic acid, ion exchange resin, mechanochemical piston packed with the particles, and collagen) are described according to W. Kuhn, A. Katchalsky, his co-workers (A. Oplatka et al.), L. Mandelkern, and the present author.
Rubber elasticity is one important factor to make theoretically clear the mechanical behavior of the mechanochemical materials. The recent theoretical and experimental results by P. J. Flory and the present author in this field are presented for polydimethylsiloxane networks and crosslinked polyacrylic acid.
Treatments towards industrial application (jack and brake by the author, and mechanochemical engine by Katchalsky et al.) are introduced. The problems to be explored for the application are also discussed.

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1) The left ventricular function could be characterized by a model of mechanical pump. However, the actual mechanisms of blood ejection and filling were more complex in the beating heart than in the ordinary mechanical pump.
2) Recent advances have shown the concepts of muscle contraction and its regulation in terms of force-velocity-length relations. However, extrapolation of such muscle mechanics to the intact heart has not been simple because each myocardial fibers did not arrange for uniform direction in the left ventricular wall. Moreover, various factors, which determined ventricular shape and size, were shown to play an important role for ventricular performance.
3) In intact beating heart, characteristics of cardiac pump function could be better understood by instantaneous pressure-volume-flow relations during cardiac cycles. The physiological and clinical meanings of pressure-volume diagrams were considered.
4) In addition to the systolic events of left ventricle, attention was increasingly focused on the behaviours of left ventricle during diastole. Therefore, recent advances in the study of diastolic properties of left ventricle are also reviewed here.

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Quantitative and objective evaluation for the rate of correct diagnosis in the doctor's reading of X-ray images is very difficult to make, but is very important especially in the case of mass screening. We studied two X-ray diagnostic systems used in mass screening, that is, (1) congenital dislocation of hip-joints in newborn infants and (2) cancer of the stomach. Both diseases are more frequently found in this country compared to other nationalities. As the methods of evaluation, receiver operating characteristics (ROC) curve and information capacity were employed. For the former disease, radiographs of 200 hip-joints were read by five specialists and six orthopedists. Out of 200 joints, 26 were confirmed to be abnormal and 174, normal. Percentages of true positive (TP) and false positive (FP) were obtained from the results of interpretation of the doctors mentioned above. On the other hand, two diagnostic methods using simple anatomical geometry were evaluated for their diagnostic abilities by tracing manually the edge of bones and measuring the geometrical features. The methods used were (1) Hilgenreiner's height (H) and (2) Uziie's angle (β). The ROC plots of the two methods were compared with those of the doctors. It was found that Uziie's angle had a better diagnostic ability than Hilgenreiner's height and, moreover, it proved to be almost identical with that of the average specialists.
For the latter disease, results of radiographic interpretation for confirmed cases of stomach cancer were mainly obtained from the data file of the Center for Adult Diseases, Osaka City. In this case, the ROC curve was drawn using percentage TP and FP obtained as a function of confidence level of malignancy, and several X-ray imaging systems for stomach were intercompared. The evaluation of this study is still preliminary, but it will serve as a basis for further investigation on optimization for screening in stomach cancer.

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Though the trend analysis on data series is very important for the clinical decision making, the objective formulation of the analysis-still remains an inexperienced area. An attempt has been made to develop analyzing methods that would correspond to the sequential changes of clinical data, through an experimental subject of the prognostic estimation of patients with acute myocardial infarction.
Twenty nine cases were divided into two groups, one consisting of 19 who survived a period of two weeks to one year and half after the attack, and the other, who died in the same period. S-GOT, S-LDH, percentage of stab form neutrocytes and blood sedimentation rate were chosen as statistically and clinically significant variables. The analysis was made with two approaches, one being retrospective and the other, prospective.
In the retrospective approach five parameters were extracted so as to represent the characteristics of the data trend pattern. Twenty variables (4 measurements×5 parameters) employed in the discriminant function was effectively reduced to five by an algorithm using the indices of discriminant efficiency and F test.
In the prospective approach, the one-month period after the attack was divided into four intervals by the 4th, 8th and the 16th days. The principal component analysis was first made by contrasting the maximum with the minimum value of measurements in each interval for each patient. A common direction going from the 4th to 2nd quadrant was observed between the survival and dead groups and between the minimum and maximum values. This suggests that the higher measurement values in each interval will indicate the worse prognosis. When the discrimination was made independently for each interval, the probability of miss-classification with F test increased in the order of the 2nd, 3rd, 4th and the 1st intervals.
The retrospective approach is not regarded as favorable because of the delayed decision and the low accuracy of the measurement; the prospective approach is more useful from the view point of clinical practice.

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In order to elucidate the diagnostic implication of human body surface cardiac potential distribu tion, a computational reconstruction method for the body surface isopotential map (hereafter abbreviated as map) was developed by using the results of simulated ventricular propagation process, and the transfer impedance vectors which were actually measured with a human torso model.
For determining the values of the transfer impedance vectors in vast numbers, an automated processing system was designed, which was composed of a switchbox, amplifiers, a multiplexer, A/D and D/A converters, a minicomputer (core memory : 4 kw), a monitorscope and output devices.
Eighty-one electrodes implanted in the torso model were connected to the 9-channel switchbox. As often as an artificial dipole was successively moved on 392 positions which cover a ventricular area in the torso model, it was energized by a unit of sinusoidal current (100 Hz, 3 mA) in the three orthogonal directions and then the potential differences between each of 81 electrodes and Wilson's central terminal were fed to the switchbox. By switching manually, every nine out of 81 potential differences was simultaneously amplified, and scanned by the multiplexer. These analog-signals were A/D converted with a sampling rate of 2000/sec, and summed up with theminicomputer by an on-line procedure. These digitized values were D/A converted to be displayed on the monitorscope for the verification of the data. If found acceptable, these values were printed by teletype and punched out on paper tapes. In, such a way, about hundred thousand values of transfer impedance vectors were measured.
Utilizing these values, 81 potential values on the torso at each stage of the simulated ventricularpropagation process were calculated mathematically with a large computer, and the maps were drawn automatically by an X-Y plotter.
When these reconstructed maps were compared with those of normal human subject, the result showed that both map patterns were similar to each other. Therefore, it was recognized that this, reconstruction method for the maps was appropriate for most parts.
In relationship between ventricular activation and the maps, main wavefronts in the ventricular model at each stage were reflected properly on the reconstructed maps. Consequently, it is considered that the maps represent the ventricular activation more spatially and visually than conventional electro-and vector-cardiograms.

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Monitoring of core temperatures of the body is informative especially in cardiac surgery. Deep body temperatures (DBTs) during and after operation were studied in over 80 patients. Improved deep body thermistors were attached to the patient's forehead (F), chestwall (C), palm (P) and heel (H). DBTs of each sector were indicated by continuous recordings and digital displays. Central deep body temperatures (CDBTs) of F and C were found to keep steady but peripheral ones (PDBTs) of P and H were labile. CDBTs are usually higher than PDBTs. F-DBT is the highest and distinctive from others. During cardiopulmonary bypass (CPB), F-DBT showed the quickest responses to warming and cooling. After CPB, PDBTs promptly rose close to the level of CDBTs.All DBTs gradually, converged into narrow range and continued to rise up to 38-39°C.
Early dissociation between CDBTs and PDBTs is the alarming sign of postop. hemodynamic crisis. There is no circulatory failure if CDBTs and PDBTs remain within narrow ranges in spite of low blood pressure.
DBTs seem to reflect the blood flow in the core of the monitoring site. Continuous monitoring of DBTs is effective in early detection of hemodynamic disturbances.

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