Generalized bronchial lesions, which would cause expiratory disturbance even in spontaneous respiration, are not found in emphysematous lungs. Obstructive expiratory disturbance as one of the most characteristic clinical symptoms of pulmonary emphysema can therefore, appear only in forced expiration, as a result of, compression of large bronchi by extraneous force originating from the thoracic wall. The prevalence of forced expiration in emphysema patients is attributed to deteriorated efficiency of spontaneous expiration, and expiratory dynamics are developed with the aid of anatomical findings of autopsied lungs. The strain and stress of the pulmonary elastic system is expressed as F(x)=A (e^ax-1) where x is the strain, F(x) the stress at x, and A and a are constants, of which the latter is determined by the physical property of the elastic system. The differential equation of, spontaneous expiration is dt/dP=-3RV₀/P². (e^ax-1) (1+x) ³/ (az+a-2) e^ax+2 and P=Ee^ax-1/ (1+x) 2where P is intrapulmonary pressure, t, time, R, total airway resistance, V₀, total lung volume in relaxation, and E, the density of the pulmonary elastic system. In emphysematous lungs V₀ is increased to 2 to 3 times the normal, while E is lowered to half the normal value. Computer analysis of the expiratory differential equation with the parameters obtained from the measurement on autopsied lungs reveals that expiratory efficiency is extremely lowered in emphysematous lungs. The main causative agent of the disturbance is the enlarged V₀, whereas the reduction in E plays a rather subordinate role.

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Implantation of a total artificial heart is considered technologically feasible at present. The purpose of this work is to define the chest cavity of an adult human for an artificial heart to be implanted. This effort is only the first stage in accomplishing the ultimate goal, that of defining not only the chest cavity, but the relative location of pertinent soft structures, such as the great blood vessels within this cavity, in the human.
In order to determine the mean dimensions for design of the blood pump, a special technique has been developed. The shape model was produced by transversely sectioning molds of the chest cavity of human cadavers. The normalized shape and curvature of the human chest cavity was determined by analysis of these data on a computer. This technique was combined with the measurements of relatively small quantity of characteristics dimensions from one hundred pairs (poserio-anterior arid lateral view) of human plane chest radiographs. The results were presented as scale drawings of the walls of the thorax as a function of the percent of the population having sizes smaller than the given curves. The beauty of the modelling and analysis is the usefullness in the ultimate clinical application of the artificial heart. This can be done by taking standard chest radiographs of the proposed recipient of the artificial heart to insure that the prosthesis will fit in the available space of a particular patient.

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Fundus photographs are widely used in diagnosis of hypertensive diseases to facilitate the early detection of changes in arteriolar vessels.
This type of disease is responsible for the great majority of fatal illnesses in Japan.
Among the many kinds of abnormal phenomena which can be observed in fundus photographs the arterio-venous crossing phenomenon is one of the most important factors in evaluating the degree of arteriolar change ; moreover, the degree of change considered to be quite difficult to recognize automatically.
In this paper, the authors describe a system of image processing and an automatic recognition method of crossing phenomena.
The processing flow of this system is as follows :
1) Improvement in the quality of images with the aid of color information (pre-processing).
2) Extraction of the contour lines of blood vessels from black and white photographs (feature extraction).
3) Quantitative classification of the grades of crossing phenomena, which agree with visual classification by physicians (classification).
A recognition experiment on nine samples has been carried out under a fully automatic system.
In the experiment a successful distinction was made between normal crossing sites and abnormal crossing sites, attaining full agreement with the physician's judgment.

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There are many papers on the vibratory sensation for vibrations perpendicular to the skin but only a few papers on vibratory sensation for practical applications are available.
This paper deals with vibrotactile stimulations that are suitable for a reading aid for the blind.
We present psychological and physical experiments carried out by using a vibrator as an improved speaker for triangular, saw-toothed and square waves. The measuring portion is on the left middle finger. The results show that the vibrotactile sensation is considerably influenced by the shape and magnitude of the vibrator area.
Moreover the new vibrator's power consumption is shown to be lower than that of a conventional vibrator by one fifth.
Consequently, the fundamental data for designing a practical reading machine were obtained, which seem to be useful for studies on a reading aid for the blind.

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An optimum method for designing AMHTS system (Automated Multiphasic Health Testing and Services System) is proposed. In this method, the optimum system is determined by 0-1 integer programming under the given medical and economic conditions, which are specified by the user.
Fundamental factors, which should be taken into considerations in the above procedure, are as follows;
(1) number of diseases that are expected to be detected at the center.
(2) mutual priorities among the diseases.
(3) the cost.
(4) the number of persons per day.
Therefore, the performance of the resultant systems is also measured by the same indexes mentioned above.
In this paper, the optimal system design algorithm and some users' constraint conditions are discussed. Some numerical examples are also presented.

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There is an urgent need for determining the correct constitutive laws of vascular walls because their mechanical properties have been recognized to be closely related to the cardiovascular disease. Accurate knowledge of vascular rheology is also required for an intelligent design of artificial blood vessels. The mechanical properties of arteries have been studied extensively using infinitesimal strain theory, and they have recently been determined on the basis of finite deformation theory.
However, few research works have been done for evaluating them in the triaxial condition. The purpose of the present paper is to modify the stress-strain relation of vascular walls in the circumferential direction, which was proposed by Hayashi et al. in 1974, and to extend it to a triaxial form.
Static analysis of large elastic deformation was carried out for an axisymmetric cylinder on the assumption of homogeneity and incompressibility. The final relations between stresses σ_γ, σ_θ, σ_zand extension ratios e, λ_θ λ_z became :
σ_θ=σ_γ+ {A (λ_z²-1) +1} *exp {B (λ_θ²-1)} -1,
σ_z=σ_γ+ {C (λ_θ²-1) +1} *exp {D (λ_z²-1)} -1.
σ_γ={ A (λ_z²-1) +1} ∫^R0Rexp {B (λ_θ²-1)} dR/R-∫^R0RdR/R,
where A, B, C and D are materials constants. These values of A, B, C and D were determined by using the iterative calculation for excised common carotid arteries and femoral arteries. The calculated results of force-displacement relations agreed well with the experimental data.
The calculated distribution of three components of stress through the wall thickness showed that the radial component of stress was negligibly small in comparison with the other two stress components. In such a case, the relations between stress and extension ratio were simplified in the following form;σ_θ= {A (λ_z²-1) +1} *exp {B (λ_θ²-1)},
σ_z= {C (λ_θ²-1) +1} *exp {D (λ_z²-1)}
These equations are practically useful because each of them includes only two materials parameters.

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