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Abstract. Psychological responses to two kinds of sound stimuli (scary and soothing), as assessed by the Anterior Asymmetry and Emotion (AAE) and Comfort Vector (CV) models which are based on the prefrontal alpha wave, were investigated and the relation between their results is discussed. For the scary sound stimulus, subjects who showed greater withdrawal motivation (AAE) displayed a decreased pleasant state (CV), while subjects who showed higher approach motivation displayed opposite affective direction. There was a correlation between the AAE and CV models for the scary stimulus, but no correlation for the soothing stimulus. Both motivational and affective states could be evaluated by a combination of AAE and CV models. We suggest that joint consideration of these two models could lead to the multifaceted evaluation of a psychological state.

This paper proposes an application that analyzes and displays electrocardiograms (ECG; electrical activity of the heart over time) and plethysmograms (PTG; pulse waves produced by the heart pumping blood to the periphery) measured simultaneously. Recently in developed countries, chronic conditions typified by lifestyle-related diseases have become the leading cause of death. Simplified monitoring of the condition can be an effective approach to disease prevention and health promotion. We have focused on autonomic nervous system activity (ANSA) because it responds to stress as well as to changes in dietary patterns, and is correlated with hypertension, the source of some diseases, such as coronary disease. In this paper, we deal with both ECGs and PTGs as part of the biological data that reflects ANSA. The proposed application enables doctors to seamlessly negotiate analyzed waveforms and index charts of ECGs and PTGs in sync with each other. It also helps them comprehend the transition of ANSA. It offers a user interface (UI) that enables doctors to observe the two measures and the relationship between them for a quick assessment of ANSA; the sonification function of the ECG indices is implemented for providing the multi-modality of the UI. An experiment was conducted to confirm the feasibility of the analysis method of the application.

Evaluation of psychological stress or state of mind remains an important problem. The anterior asymmetry and emotion model (AAE model) is a conventional and widely used method to sort baseline affective styles (approach or withdrawal) based on asymmetry of the activity in prefrontal cortices. Another method is to use alpha wave fluctuations at the frontal poles, as proposed by Yoshida. This method estimates state of mind as one point on a comfort level surface with pleasant-unpleasant and excited-calm axes that are normal to each other. The aim of this paper is to investigate the validity of the Yoshida method through the psychological responses to sound stimuli. Twenty-two healthy graduate students listened to two kinds of sound clips (scary and soothing) to induce negative and positive emotional states. The results showed that there are significant differences between the responses to scary and soothing sound stimuli in both unpleasant and excited mood states. Compared with baseline, increases in unpleasant and excited mood states were found in response to scary stimuli. However, no significant changes from the baseline state were observed in response to the soothing sound stimulus. These results suggest that the fluctuation of alpha waves recorded at both frontal poles is a valid index for the evaluation of psychological state of mind, especially for negative stimulation. Future study plans include investigating a possible relationship between the AAE model and the Yoshida method.

The aim of this study was to investigate the effects of vegetable tablets containing Gamma-Aminobutyric Acid (GABA) intake on cardiovascular response and the autonomic nervous system in young adults. In a double-blind, randomized controlled trial, 7 healthy subjects were assigned to take vegetable tablets (10 g/trial) or control tablets (10 g/trial). We measured heart rate (HR), systolic and diastolic blood pressure, stroke volume, cardiac output, total peripheral resistance index, and the low- and high-frequency oscillatory components of heart rate variability (HRV). Two major spectral components were examined at low-frequency (LF: 0.04-0.15 Hz) and high-frequency (HF: 0.15-0.4 Hz) bands to indicate HRV. There were significant interactions in HR (p

To study brain mechanisms of memory scan, we have measured event-related potentials (ERPs) during the execution of a Sternberg task concerned with movement directions of random dot patterns (RDPs). Five healthy male subjects participated in the experiment. Event-related potentials were recorded at 20 electrode positions over the entire head. A prominent positive ERP component peaking at 380–390 ms known as P300 was observed in the parietal region after the presentation of the probe moving random dot pattern, whereas the P300 was not observed after the presentation of a control stationary RDP. On the other hand, a positive ERP component peaking at 127 ms was commonly observed in the occipital region after the presentation of both moving and control stationary RDPs. These findings suggest that P300 may reflect cortical activities related to the memory scan of movement directions of RDP.

We introduce a precise analytical method for computing the temporal changes in concentration and fluxes of gene-regulating repressor protein particles. The temporal changes in repressor particle concentration is described by an integral-differential diffusion equation in cylindrical coordinates. The equation consists of the memory-less first-time-arrival probability and the integration of the return probability of the particles to the operator region of the DNA. By using the Laplace transformation, we could derive analytical forms of the temporal changes in concentration and flux in a radial direction, the total flux, and the first-time-arrival probability. We also computed the impulse responses of the first-time-arrival probability of the repressor to the sink. The computed diffusion of the repressor particles decreased rapidly from the onset of the reaction. As the diffusion constant in the medium around the DNA increased, the first-time-arrival probability, the diffusion, and the flux of the particles decreased, while the total flux into the target sink increased. As the chemical factor became predominantly a diffusion factor, the first-time-arrival probability, the diffusion, and the flux of the particles decreased. As the dissociation rate of the particles increased, the flux into the sink increased. The number of dissociated particles was significantly more influenced by the chemical factor than by the diffusion. The first-time-arrival probability oscillated significantly at the onest of the reaction. When this method has been extended, it will be available for predicing genetic expression and creating artificial life.

Preliminary experiments were carried out to investigate the feasibility of using an electroencephalogram and heart rates to evaluate the efficacy of finger acupressure on the key points of planta pedis (both soles). Continuous electroencephalograms were recorded from 19 electrodes based on the International 10-20 electrode placement system on 22 university students (21+/-2.3 years). Spectral power changes were obtained at each electrode site. The power of the alpha1 frequency range (8-10 Hz) increased slightly during acupressure although no statistical significance was observed, while heart rates decreased in all subjects (p

This paper describes a self-tuning method of membership functions in a fuzzy-logic-based cardiac pacing system and validates its feasibility in a double sensor system which has minute ventilation and oxygen saturation level as its guides for the rate regulation. Though the agreement between the pacing rates (fuzzy rates) calculated with three linguistic variables for each parameter and the target rates were not satisfactory, it was improved significantly by tuning the membership functions. Almost the same evaluated values with those obtained by using six linguistic variables for each parameter were obtained. Time required for the self-tuning process was about 40 s (386CPU, 20 MHz) which was fast enough for the system. The smaller number of linguistic labels results in a smaller number of rules, which is beneficial in implantable cardiac pacemakers with limited memory capacity. A fuzzy-logic-based cardiac pacing system is promising for the realization of custom-made cardiac pacemakers.

A small and light-weight wearable electrocardiograph (ECG) equipment with a tri-axis accelerometer (x, y and z-axis) was developed for prolonged monitoring of everyday stress. It consists of an amplifier, a microcomputer with an AD converter, a triaxial accelerometer, and a memory card. Four parameters can be sampled at 1 kHz for more than 24 h and a maximum of 27 h with a default battery and a memory card of one giga byte (1 GB). Off-line data processing includes motion information along three axes and autonomic nervous system (ANS) activity bispectral analysis and the tone-entropy method (T-E method) from HRV data. The availability of the system was tested through simulated office work and three-day monitoring by replacing the battery and the memory card every 24 h. Both short-term and circadian rhythms of ANS activity were clearly observed. In addition, sympathetic nervous activities gradually increased from the second to the third day. The experimental data presented verifies the functionality of the proposed system.

In a healthy state, the human heart beat shows an extensive spectrum and its attractor has a chaotic orbit. However, in a damaged state, fluctuations in the heart beat become periodical. An Implantable Cardioverter/Difibrillator (ICD), along with an implanted pace maker until in either the subcutaneous chest wall, or subpectoral or subcutaneous abdomen, or sub-muscles rectus abdominis serve to detect abnormalities and eliminate them quickly. The abnormalities affected include: ventricular fibrillation (non-regulated electrical activity in a ventricle) and other arrhythmia, such as ventricular tachycardia (VT) or supra ventricular tachycardia (SVT). There are two methods for detecting arrhythmia available with the present ICD. One is to investigate the heart beat or period, and the other is to investigate the electrocardiographic wave. However, the employment of these techniques, either singly or in combination, doesn't always provide the required accuracy. This paper describes traditional analysis methods and the problems of ICD in brief. Subsequently, it discusses the chaotic approach. Finally, the results suitable for real testing, as well as future topics, are presented.

[1] Clinical trials of hypothermic brain treatment for newborn babies are currently hindered by the difficulty in measuring deep brain temperatures. As one of the possible methods for noninvasive and continuous temperature monitoring that is completely passive and inherently safe is passive microwave radiometry (MWR). We have developed a five-band microwave radiometer system with a single dual-polarized, rectangular waveguide antenna operating within the 1–4 GHz range and a method for retrieving the temperature profile from five radiometric brightness temperatures. This paper addresses (1) the temperature calibration for five microwave receivers, (2) the measurement experiment using a phantom model that mimics the temperature profile in a newborn baby, and (3) the feasibility for noninvasive monitoring of deep brain temperatures. Temperature resolutions were 0.103, 0.129, 0.138, 0.105 and 0.111 K for 1.2, 1.65, 2.3, 3.0 and 3.6 GHz receivers, respectively. The precision of temperature estimation (2σ confidence interval) was about 0.7°C at a 5-cm depth from the phantom surface. Accuracy, which is the difference between the estimated temperature using this system and the measured temperature by a thermocouple at a depth of 5 cm, was about 2°C. The current result is not satisfactory for clinical application because the clinical requirement for accuracy must be better than 1°C for both precision and accuracy at a depth of 5 cm. Since a couple of possible causes for this inaccuracy have been identified, we believe that the system can take a step closer to the clinical application of MWR for hypothermic rescue treatment.

A small and light-weight wearable electrocardiograph (ECG) equipment with three accelerometers (x, y and zaxis) was developed for prolonged monitoring of autonomic nervous system in daily life. It consists of an amplifier, a bandpass filter, a microcomputer with an AD converter, a triaxial accelerometer, and a memory card. Four parameters can be sampled at 1 kHz (10 bits) for more than 24 hours, maximum 27 hours, with a default battery and a memory card (1 GB). The availability of the system was tested for three subjects for three days by replacing the battery and the memory card every 24 hours under each environment. Both short-term and circadian rhythms of the autonomic nervous system were clearly observed. The change of the autonomic nervous system from body movement (i.e. walking or turning over) was observed by check acceleration data. The feasibility of the application in clinical practice is also discussed.

A method of retrieving a temperature-depth profile in biological object from a set of multi-frequency microwave radiometric data has been developed. The method is a combination of model-fitting and Monte Carlo techniques and is capable of estimating a profile and its confidence interval as a function of the depth. We use 2σ -intervals as a measure of the precision of tissue temperature measurements. The method was tested and supported by an experiment in which temperature distributions in a muscle equivalent agar phantom were measured using a 5-band, 1-3.8 GHz radiometer with the brightness temperature resolution of 0.05-0.07 K. A typical result of the experiment showed that 2σ -intervals were 1 K or less for 0 < z < 3 cm, 1.4 K at z = 4 cm, and 3 K at z = 5 cm. A numerical simulation study was made using this technique to assess effects of the selection of measurement frequencies, number of frequency bands, brightness temperature resolution of radiometer and thickness of fat layer on the precision. Resul...

The purpose of the study is to show the feasibility of a light-weight wearable electrocardiograph with three accelero-meters for monitoring stress in everyday life. It consists of an amplifier, a band pass filter, a microcomputer with an AD converter, a triaxial accelerometer, and a memory card. An ECG and three accelerations are sampled at 1 kHz for more than 24 hours, maximum 27 hours with a default battery and a memory card. The heart rate variability analysis program detects R waves and determines R-R intervals for 24 hours by a data acquisition algorithm. An algorithm was also developed. It was designed to reduce motion artifacts induced by body movements on ECG. Autonomic nervous activity levels are calculated based on the heart rate variability spectrum analysis. The availability of the system was tested for three subjects for three days by replacing the battery and memory card every 24 hours under each environment. Both short time rhythms and a circadian rhythm of autonomic nervous system were clearly observed. The feasibility of the system for monitoring the long-term stress level is discussed.

In order to find out the most suitable and accurate pointing methods to study the sound localizability of persons with visual impairment, we compared the accuracy of three different pointing methods for indicating the direction of sound sources in a semi-anechoic dark room. Six subjects with visual impairment (two totally blind and four with low vision) participated in this experiment. The three pointing methods employed were (1) directing the face, (2) directing the body trunk on a revolving chair and (3) indicating a tactile cue placed horizontally in front of the subject. Seven sound emitters were arranged in a semicircle 2.0 m from the subject, 0 degrees to +/-80 degrees of the subject's midline, at a height of 1.2 m. The accuracy of the pointing methods was evaluated by measuring the deviation between the angle of the target sound source and that of the subject's response. The result was that all methods indicated that as the angle of the sound source increased from midline, the accuracy decreased. The deviations recorded toward the left and the right of midline were symmetrical. In the whole frontal area (-80 degrees to +80 degrees from midline), both the tactile cue and the body trunk methods were more accurate than the face-pointing method. There was no significant difference in the center (-40 degrees to +40 degrees from midline). In the periphery (-80 degrees and +80 degrees ), the tactile cue pointing method was the most accurate of all and the body trunk method was the next best. These results suggest that the most suitable pointing methods to study the sound localizability of the frontal azimuth for subjects who are visually impaired are the tactile cue and the body trunk methods because of their higher accuracy in the periphery.

In this gaper we propose to use fuzzy sets to the rate control in a multisensor rate adaptive cardiac pacemaker system. The logic was applied to the rate determination tased on minute ventilation and oxygen saturation during walking.

One of the recent problems for pacemaker (PM) patients is an anti-shoplifting system which is called the electronic article surveillance (EAS) system. Electromagnetic field patterns of the two types of EAS system, radio frequency (RF) and electromagnetic (EM) systems, are simulated with in Irnich model which consists of saline and a pacemaker. The voltage differences induced between a PM casing main body and the tips of pacing leads and those between both leads (ventricular and atrium) are estimated. The voltages induced between PM body and the ventricular lead are about 300 mV and 1 mV by RF and EM systems, respectively. Considering the input characteristics of the PM circuit, these voltages will not bring about serious errors in the PM system if the patient goes through the EAS gate at a normal pace. Acousto-magnetic EAS systems which use lower frequencies may be more harmful to the PM system.

Hypothermia is proposed as a treatment for hypoxia-ischemia in newborn infants who suffer serious cerebral injury or die, if they are brought back early. In this treatment the deep brain temperature monitoring which is noninvasive and continuous is required. Multifrequency microwave radiometry (MWR) is one of the promising candidates for that purpose, and we have been developing a five-band microwave radiometer system and appropriate data processing methods. This paper is to describe the current status of a newly designed MWR system which operates in a normal room with various electromagnetic background noise. Temperature resolutions of the five receivers were obtained by a calibration experiment using a temperature-controlled water-bath. The results of a temperature retrieval simulation experiment is also presented.

An experimental three-band (1.5,2.5,3.5+-0.5GHz) radiometer system and a data analysis procedure have been developed for noninvasive measurement of the temperature at various depths in a biological body. Using them, we made temperature measurement experiments on the abdominal region of rabbits. The results of the experiments demonstrate the feasibility of the multifrequency radiometry for this purpose.

Recent simulation studies have shown that a technique of multi-frequency microwave radiometry is feasible for non-invasive measurement of deep brain temperatures in the new-born infants. A five-band microwave radiometer system has been developed, and its operation in a normal electromagnetic environment is checked. Five receivers operating with a waveguide antenna and at center frequencies of 1.2, 1.65, 2.3, 3.0 and 3.6 GHz (0.4 GHz bandwidth) are calibrated using a temperature-controlled water-bath. Temperature resolutions obtained for each receiver are 0.183, 0.273, 0.148, 0.108 and 0.118 K, respectively. A temperature retrieval simulation based on these resolutions and the previously proposed algorithm shows that the confidence interval, as produced by thermal noise, is 0.62 K for the retrieved central brain temperature. If the conductivity of brain is estimated wrong by 10 %, this will result in an error of 0.3 - 0.4 K. The result of this work is encouraging for realization of radiometric measurement of temperature profile in a baby's head.

An assessment is made of the degradation that is caused by a water-filled bolus in the precision of tissue temperature measured noninvasively by a five-band microwave radiometry scheme. The precision is expressed in terms of the confidence interval of tissue temperature estimated from a set of five brightness temperatures measured with an experimental instrument operating at center frequencies of 1.2, 1.8, 2.5, 2.9, and 3.6 GHz, with a 0.4-GHz bandwidth. Results show that degradation due to a bolus having a thickness of about 1 cm is small when it is filled with deionized or distilled water. It is concluded that the use of water-filled bolus is permissible for microwave radiometric measurement. This is of a practical importance when the technique is used in combination with electromagnetic heating for hyperthermic treatment of cancer. >

A method was proposed for discrimination of ventricular arrhythmias using fuzzy logic. The classifier uses four features of ECG waveforms; amplitude variation ratio, interval variation ratio, peak sharpness, QRS complex width, and assigns each waveform a number of 0-100. The performance of the algorithm was evaluated on the surface and intracardiac electrocardiograms of ventricular tachycardia (VT), ventricular fibrillation (VF) and normal sinus rhythm (NSR) in mongrel dogs. NSRs were evaluated 90-100 while VFs less than 10. VTs were assigned the numbers of 30-75. An automatic detection and defibrillation experiment was performed with this algorithm.

A chaotic approach was applied to the quantitative analysis of Parkinson's disease (PD). Finger tapping tests were performed to analyze the degree of bradykinesia in PD patients. The voltage variation obtained from the tapping tests was sampled at 200 Hz, and the data for 15 seconds were used in the analysis. Sampled data were embedded into the phase space with various combinations of the dimension and delay time. The embedding dimension and the delay time used in this study were 16 and 13, respectively. Fractal dimension of 5 PD patients was calculated in the phase space and compared with those of 5 volunteers.

A small and light-weight wearable electrocardiograph (ECG) device with three accelerometers (x, y, and z axis) was developed for prolonged monitoring of everyday stress. It consists of an amplifier, a microcomputer with an analog/digital converter, a tri-axial accelerometer, and a memory card. Four parameters can be sampled at 1 kHz for a maximum of 27 h with the default battery and a 1 GB memory card. An algorithm for the reliable and clear detection of R wave peaks of ECG was also developed for accurate heart rate variability (HRV) analysis. The algorithm reduces ECG motion artifacts induced by body movements. Off-line data processing includes autonomic nervous system (ANS) activity bi-spectral analysis and the application of the tone-entropy method to HRV data. The availability of the system was tested through simulated office work and three-day monitoring. Both short-term and circadian rhythms of ANS activity were clearly observed. The experimental data verifies the functionality of the proposed system.

A method of temperature profiling in biological objects is described. In this method, thermal radiation from the object is measured as the brightness temperature by a multi-channel, topically five, 1 - 4 GHz radiometer via a contact-type, dielectric loaded waveguide antenna with a 15 X 20 mm2 aperture. Coupling between the antenna and the object is analyzed under 1-dimensional approximation. The radiometric data are analyzed by a combined method of model fitting and Monte Carlo techniques to retrieve a temperature profile in tissue and its 2 (sigma) -intervals along the axis of the antenna view field. The method has been tested by numerical simulation and agar phantom experiments to demonstrate its capability of temperature profiling in muscle with 2(sigma)

Fuzzy theory was applied to the rate control of a cardiac pacemaker which uses two parameters, respiratory rate and temperature, as the parameters for rate regulation. Using 25 fuzzy reasoning rules derived from five mongrel dogs, the pacing rates in three animals were calculated and compared with the intrinsic heart rates. It is concluded that the fuzzy method is well suited for the rate determination of a multi-parameter rate-responsive cardiac pacemaker.

Carbon fibers with fibrin glue were used as electrodes for diaphragm pacing. The electrodes were applied to three mongrel dogs and the effectiveness was tested. The carbon leads were glued to phrenic nerves by means of the fibrinogen and thrombin bilaterally. The tidal volumes and threshold current level for stimulation were measured at various time up to 9 weeks after implantation. Effective contraction of diaphragm were observed for 9 weeks. By using this electrode, the exfoliation of the nerve is not necessary, the nerve can be maintained in an intact state, and the risk of the implanting operation can be minimized.

PVF成形体より種々の条件下で製造した構造状活性炭 (SAC) の減圧下, 303～343Kにおける水蒸気吸着平衡の測定を行い, 既往の結果との比較ならびに本吸着系のヒートポンプへの適用性の検討を行った.1) 本SACは充分な水蒸気吸着容量を有する.2) 吸着平衡関係は2種に大別でき, PVF成形体を炭化・低賦活したSAC (Group-I) では低相対圧 (φ) 域での立ち上りとφの上昇に伴うゆるやかな吸着量の増大, 高賦活SAC (Group-II) ではφ≅0.5での急峻な立ち上りを示す.3) Group-Iの中でも低賦活SACは吸・脱着の可逆性に優れ, これをヒートポンプへ適用した場合, 汲み上げ温度差を大きくとれることがわかり, 本SACが吸着ヒートポンプの蓄熱材として使用しうることを明らかにした.

A new method using respiratory rate and temperature as the guides for optimal pacing is proposed. A pacemaker was fabricated which senses these two parameters simultaneously. The pacemaker functions by calculating the cardiac rate, which would be derived from the respiratory rate and the blood temperature. The higher of the two rates is adopted as the cardiac pacing rate, i.e., at which stimuli will be delivered. The operation was tested in a mongrel dog with complete atrioventricular block. After the induction of anesthesia, a thermistor temperature probe was inserted into right atrium and a respiratory rate sensor was attached around the chest. After administration of a pyrogenic drug, both respiratory rate and blood temperature increased. The pacing rate was increased from 178 beats/minute(bpm) at 36.4 degrees C, blood temperature, and 26.5 acts/minute(apm), respiratory rate, to 233 bpm at 40.1 degrees C and 40.0 apm. Cardiac output was increased from 2.15 liters/minute(l/pm) at the beginning to 2.50 l/pm at maximum. The transition of the guide from respiratory rate to temperature was observed at about 38 degrees C.

A method was developed to grow homogeneous (Ga,Al)P alloy using a temperatue difference liquid phase epitaxial growth technique. In this method (Ga,Al)P polycrystals were prepared at 1000 °C prior to the growth of (Ga,Al)P alloy at 800 °C, which acted as the Al source to maintain the alloy composition constant during the growth. Electron probe microanalysis showed that the grown alloy was uniform within 0.01 mole fraction. It was also possible to control the alloy composition by this growth technique. Measurements of photoluminescence of the grown layer and electroluminescence of Zn‐diffused diode revealed the grown alloy was of high quality. Observed edge emission energy indicated that the band gap varied with alloy composition. The edge band emission spectra with fine structure were observed at 77 K.

The In—Ga—P ternary phase diagram in the low temperature region, 600–800°C, in the In-rich corner has been experimentally obtained and calculated based on the quasi-regular model with the assumption of a non-ideal solid. The liquidus lines were determined at 600, 650, 700, 750 and 800°C by weight loss method. The solidus compositions were measured on the epitaxial layers grown by the temperature difference method. Fairly good agreement between the data and calculated results was obtained.

A large waveguide applicator is proposed for deep regional hyperthermia, where a part of a patient's body is exposed to the TE/sub 10/ -mode waves in the rectangular waveguide through the holes made to fit the body cross section in the broad walls. The electric field and the specific absorption rate distribution produced by the applicator in a realistic model of a human body cross section calculated by a two-dimensional (2-D) numerical method are given.