The dynamic viscoelastic properties of sputum have been studied using the conventional dynamic method and the newly developed Raised Cosine Pulse (RCP) method. The sputum samples obtained fresh in the morning were stored at room temperature (about 20°C) in closed containers until use. Measurements were made within 4 hours of expulsion. Each test required only about 1.5 ml of sputum.
1. Conventional dynamic method. A thixotrometer (coaxial cylinder type) was used for the experiments. Dynamic viscosity (η′), storage modulus (G′) and loss modulus (G″) were obtained over a range from 10-² to 10⁰ rad/sec in angular frequency.
1-1) 13 sputum samples (mucoid 4, mucopurulent 3, purulent 6) were obtained from 11 patients with chronic obstructive lung disease (COLD). Measurements were carried out at 37°C. All samples showed similar frequency dependence. With an increase in frequency, η′ decreased linearly and steeply, but G', on the other hand, increased slowly.
1-2) The effect of expectorants on the viscoelasticity of sputum was examined by adding them to purulent sputum samples. The measurements were carried out at 25°C. (a) After adding 20 % N-acetyl-L-cysteine the samples were then subjected to shear at 5.0 rpm for 10 minutes. The values of G″ revealed only slight decreases, but the values of G' showed extreme reduction. (b) With 0.2% bromhexine, no significant decrease was observed in dynamic viscoelasticity. (c) In 10 and 30 minutes after adding 0.5% seaprose-S, the values of G′ and G″were found greatly. decreased.
2. RCP method. Rheopexy-Analyzer was used for the experiments. 11 sputum samples (mucoid 5, purulent 6) were obtained from 8 patients with COLD. Measurements were carried out at 37°C. The values of dynamic viscoelasticity obtained were over the range from 10-³ to 10⁰ rad/sec in angular frequency, and were roughly in agreement with those obtained by the conventional dynamic method in almost all samples. A peak of G″ which indicated a relaxation region near 10-¹ rad/sec was observed more evidently in purulent sputa than in mucoid sputa. In 4 samples of purulent sputa, the value of G′ and G″ showed a sequential decrease during 60 minutes. The dynamic mechanical behavior obtained from sputa has been predicted with a mechanical model combining Maxwell and Voigt elements in a series.

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A mathematical model of the stretch reflex system of soleus muscle in cat, consisting of muscle, muscle spindle and alpha motoneuron is constructed based on the physiological knowledge. By using this model the stretch reflex responses are explained.
Mechanical properties of the muscle, such as muscle tension-impulse frequency of alpha motor nerves, muscle tension-length relations and viscoelastic constants, are in the first place deter-mined on the basis of the results of experiment using the soleus muscles of a cat.
In the second place, constants of the muscle spindle and nervous system are estimated by simulating the experimental results involving the stretch reflex (responses of muscle tension arising as reflex under stretching of the soleus muscle). The responses of this model are in good agreement with the results of physiological experiments. This model also explains the characteristics, that when the activity of gamma route is high, the rate of tension increase in line with the stretch of muscle is high.
Using this model, the relation between the change of muscle length caused by a load on the muscle and the sensitivity of muscle spindle, is discussed.

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A two-dimensional displaying method (arrow map) for displaying MCG's, which are distri-bution-of the normal component of magnetic field (B_n) on the chest due to cardiac generator, is presented. This is a two-dimensional gradient form of B_n displayed as an array of arrows.
The arrow maps of one normal and two abnormal heart subjects are presented here to demon-strate that the cardiac generators can be roughly estimated by visual inspection of these maps. It is also found that B_n on the chest is in large part produced directly by cardiac generator.
It is seen in this paper that the arrow map allows one to visually determine some simple combination of cardiac generators, as a simple solution to the magnetic inverse problem. It is also seen that the effect of the torso boundaries on the MCG of B_n does not degrade the visual determination of the cardiac generator from the arrow patterns.

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This paper provides a theoretical complement to the authors' previous paper from the spatialfilter point of view.
First, the spatial loop transfer function is introduced as a successful means of explaining the spatial frequency characteristics of the computer model.
Next, a continuous model is introduced on the basis of stochastic considerations showing the generality of the spatial characteristics of the computer model.
The conclusion is that the systems recurrently inhibited through the parallel fibers are apt to relatively intensify the spatial wave components with wavefronts crossing the parallel fibers.
Thus, a suggestion is derived that Golgi cells may tend to arrange the transfer gain of mossy fiber input in a wave-like manner along parallel fibers.

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