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Dynein from inner arms of Chlamydomonasflagella contains sevendistinct subspecies, a through g. Several lines of evidence suggest thesesubspecies play important roles in generating flagellar beating and thatthe different subspecies are functionally diverse. To evaluate theirroles and diversity, the mechanical properties of subspecies-c, which isa single-headed motor, were examined using optical trap nanometry. Apolystyrene bead coated with a small number of subspecies-c moleculeswas captured with the optical trap and brought into contact with amicrotubule fixed to a coverslip. Movements of the bead were measured bya quadrant photodiode sensor with sub-nanometer- and millisecond-resolution.Beads carrying a single active subspecies-c molecule moved processivelyalong the microtubules in 8-nm steps but slipped backwards under highloads. Force-velocity relationships of single subspecies-c molecules werealmost linear and the shapes of the normalized curves at 5 μM and 100μM ATP were similar. These results indicate that dynein subspecies-cfunctions in a very different way from conventional motor proteins, suchas myosin and kinesin, and has properties that could produceself-oscillation in vivo. [ABSTRACT FROM AUTHOR]

The prevention of vibration syndrome among Japanese forest workers using chain saws and bush cutters involved three goals. The first was to introduce exposure‐time regulations in the chain saw and bush cutter industry. The second was to improve the chain saw and bush cutter to reduce the vibration transmission. The third was to find effective tests for the early diagnosis of vibration syndrome. How these three goals were met is discussed.

Abnormal septal motion on M mode echocardiography was seen in eight of 16 patients soon after non-surgical closure of the ductus arteriosus. Ten to twenty-nine months after the procedure the abnormal septal motion had disappeared spontaneously. The cross section of the left ventricular cavity was circular both when septal motion was abnormal and when it was normal. Cross sectional echocardiography showed that there was an exaggerated anterior swinging motion of the heart in systole in patients with abnormal septal motion on the M mode recordings. The left ventricular end diastolic diameter before closure was significantly larger, and its reduction after closure was more pronounced in those with abnormal septal motion than in those without. This suggested that the abnormal septal motion was associated with relief of long standing left ventricular volume overload. It is suggested that acute shrinkage of the heart caused temporary laxity of the pericardium, and consequently more movement of the heart within the thorax. The return of normal septal motion suggests that the pericardium gradually shrank to accommodate the smaller heart. [ABSTRACT FROM PUBLISHER]

Pulsed Doppler echocardiography in healthy individuals often shows a disturbance of diastolic flow in the right ventricular outflow tract just below the pulmonary valve that suggests regurgitation. This disturbance of diastolic flow was studied in 50 healthy individuals and 40 patients with cardiopulmonary disease, some of whom had a pulmonary regurgitant murmur. Diastolic flow was disturbed in 39 of the 50 healthy individuals. In 32, cross sectional echocardiography gave a satisfactory image of the pulmonary valve. The characteristic Doppler signals usually lasted throughout diastole, were directed toward the right ventricular cavity, and gradually waned towards end diastole; they formed a spindle shaped area of abnormal signals that extended to within 10 mm of the coaptation of the pulmonary valve towards the right ventricular cavity and the pressure difference estimated from the signals by the modified Bernoulli equation seemed to be proportional to the normal retrograde transpulmonary pressure difference. In all 40 patients with cardiopulmonary disease, signals indicating pulmonary regurgitation were found whether or not a regurgitant murmur was present. When it was present, however, the spindle was longer than 20 mm and in patients with pulmonary hypertension the velocity of abnormal diastolic flow was higher than in healthy individuals. The Doppler signals registering disturbed flow in the healthy individuals resembled the signals caused by pulmonary regurgitation in the patients in terms of location, orientation, and configuration. These results show that healthy individuals usually have trivial pulmonary regurgitation. In practice the distance that the flow disturbance extends from the valve and estimated pressure difference across the valve are probably the most important variables for assessing the clinical significance of pulmonary valve regurgitation. [ABSTRACT FROM PUBLISHER]

Abnormalities of the mitral valve in patients with pulmonary stenosis, tetralogy of Fallot, and pulmonary hypertension with right ventricular pressure overload were studied by real time cross sectional echocardiography. Dislocation of the anterior and posterior mitral leaflets at the coaptation zone in systole was present in 16 of 46 cases: nine of 11 (82%) cases of pulmonary hypertension, four of 20 (20%) cases of tetralogy of Fallot, and three of 15 (20%) cases of pulmonary stenosis. The incidence was highest in patients with pulmonary hypertension. In eight of the 16 patients with mitral valve lesions, mitral regurgitation was seen on left ventriculograms or cross sectional Doppler echocardiograms. The dislocation was located near the posteromedial commissure of the anterior mitral leaflet in all cases. These findings are similar to the mitral valve abnormalities seen in patients with secundum atrial septal defect, and therefore may be due to a common cause. No relation could be found between the left ventricular deformity index and the incidence of dislocation of the mitral leaflets. Thus, the reason why this mitral valve abnormality occurs in conditions with right ventricular pressure overload could not be established. [ABSTRACT FROM PUBLISHER]

The Doppler echocardiographic features of coronary arteriovenous fistula were investigated in eight patients with left or right coronary arteriovenous fistulas who had a continuous heart murmur in the upper precordial area and whose diagnoses were confirmed by coronary angiography. In four patients the dilated lumen of the coronary arteriovenous fistula was visualised by cross sectional echocardiography. Of these, three showed abnormal unidirectional continuous flow signals with broad velocity spectra in the fistula. Abnormal, powerful, unidirectional or bidirectional continuous Doppler signals were detected in part of the pulmonary artery in two of the eight patients, in part of the right ventricle in two, and in part of the right atrium in one; these signals were interpreted as indicating shunt flow. Although the opening of the fistula was difficult to visualise by cross sectional echocardiography, the pulsed Doppler technique helped identify the site in patients with dilatation of the coronary artery. In the remaining three patients with a small shunt no abnormal findings were obtained with cross sectional echocardiography or the Doppler technique. The size of the fistula below which no abnormal findings may be obtained by Doppler echocardiography still needs to be determined. [ABSTRACT FROM PUBLISHER]

Blood flow patterns were analysed at nine points in the pulmonary area using the pulsed Doppler technique combined with cross-sectional echocardiography in 53 patients with heart disease and 10 healthy subjects. In subjects with a normal pulmonary artery pressure the blood flow pattern in systole showed a gradual acceleration and deceleration with a rounded summit in mid systole, designated the round type. In patients with pulmonary hypertension it showed a rapid acceleration and early deceleration with a sharp peak in early systole, designated the triangular type. The acceleration time index, defined as the ratio of the time interval from the beginning to the peak of ejection to the ejection time, showed a significant inverse correlation with mean pulmonary artery pressure. In pulmonary hypertension a prominent reverse flow occurred in the right posterior part of the pulmonary trunk during mid-systole and early diastole, indicating the presence of a vortex. Similar flow patterns were also seen in patients with idiopathic pulmonary artery dilatation. The factors responsible for the triangular type were principally the reduced capacitance and increased impedance of the pulmonary vascular tree. Those responsible for the reverse flow were the curved path of the blood flow and dilatation of the pulmonary artery. [ABSTRACT FROM PUBLISHER]

Abnormal echocardiographic findings in seven cases of bioprosthetic valve endocarditis were confirmed in six at operation. The echocardiograms showed three cases with thickening and increased echo intensity (group 1) and four (group 2) in which vegetations were seen initially without either of the two features in group 1. Two patients in group 1 had vegetations, the causative organism being a streptococcus. Staphylococcus epidermidis was the causative organism in three of the four cases in group 2; in two of these rapidly growing vegetations were detected. The large vegetations obstructed the ostium of the bioprosthetic valve. Thus if vegetations are detected in cases in which staphylococci are the causative bacteria surgery should be performed as soon as possible. In patients who develop a fever after bioprosthetic valve replacement and especially in those with evident bacteraemia echocardiography should be repeated frequently so that lesions may be detected early. [ABSTRACT FROM PUBLISHER]

Mitral regurgitation and its haemodynamic features were investigated non-invasively in cases of hypertrophic cardiomyopathy by means of two dimensional Doppler echocardiography. There were 28 patients, 14 of whom showed systolic anterior motion (SAM) of the mitral echo; the other 14 did not. The following results were obtained. (1) Mitral regurgitation was detected by the Doppler technique in all cases with systolic anterior motion of the mitral echo and in half of those without it. (2) Doppler signals of mitral regurgitation started immediately after the first heart sound. (3) Mitral regurgitant flow was often distributed from the entire mitral orifice over the entire or the posterior half of the left atrium in the cases with systolic anterior motion. In the cases without systolic anterior motion the regurgitation was usually localised near the mitral orifice. These features differ from those of regurgitation usually seen in rheumatic mitral valve disease and idiopathic mitral valve prolapse. (4) The Doppler technique and left ventriculography were equally efficient in detecting mitral regurgitation. (5) The early systolic component of the murmur of hypertrophic myopathy is considered to result in the main from concomitant mitral regurgitation, but not from turbulent blood flow in the left ventricular outflow tract, so that in cases with mitral regurgitation as a complication, mitral regurgitation may also contribute to the development of the midsystolic portion of the systolic murmur, while the main origin of this portion of the murmur is the left ventricular outflow obstruction. [ABSTRACT FROM PUBLISHER]

The mechanism of systolic anterior motion of the mitral valve and the localisation of the intraventricular pressure gradient were determined in 15 cases of hypertrophic obstructive cardiomyopathy by the combined use of real time two dimensional echocardiography and intracardiac manometry. We arrived at the following conclusions. The systolic anterior motion of the mitral echo in the M-mode echocardiogram can be classified into two types, I and II, based on two dimensional echocardiographic findings. In type I, the echo sources of systolic anterior motion are the anteriorly shifted mitral chordae and, in part, the papillary muscles. The intraventricular pressure gradient occurs at the level of the tip of the papillary muscle. The suprapapillary part of the outflow tract and the inflow part show a low pressure, while the apical cavity shows a high pressure. In type II, the echo sources of systolic anterior motion are the anterior and posterior mitral leaflets which are oriented in such a way as to obstruct the outflow tract. The pressure gradient occurs at the level of the anterior and posterior mitral leaflets. The inflow tract and the outflow tract just below the mitral leaflets show a high pressure, in contrast to type I systolic anterior motion. The inappropriate and maloriented papillary muscles play an essential role in causing both types of systolic anterior motion and outflow obstruction. The direction of the axis of the papillary muscle is changed in late systole, moving its tip away from the interventricular septum, resulting in a simultaneous reduction in systolic anterior motion. [ABSTRACT FROM PUBLISHER]

Mitral valve lesions accompanying secundum atrial septal defect were examined in 120 successive patients from May 1978 to December 1980 using real time two dimensional echocardiography. The conclusions were as follows: (1) The characteristic feature of the mitral lesion accompanying secundum atrial septal defect is a dislocation of the mitral leaflet toward the left atrial side in the area of coaptation. (2) The mitral lesion is seen in about half the patients with secundum atrial septal defect. (3) It is usually seen only in the anterior leaflet, and is found near the posteromedial commissure. Lesions in other sites on the leaflet all accompany those near the posteromedial commissure. (4) The incidence, extent, and degree of the mitral valve lesion increase with age. (5) It is assumed that the mitral valve lesion in secundum atrial septal defect starts near the posteromedial commissure in the anterior leaflet, gradually deteriorates, and extends toward the anterolateral commissure. (6) It is probable that the mitral lesion results in mitral regurgitation. (7) The mitral valve lesion is similar in appearance to mitral valve prolapse caused by the floppy mitral valve, though their causative factors may be different. It is probably the reason why the mitral valve abnormality has been described as mitral valve prolapse in previous reports. In the present study the mitral lesion was evaluated on the distance of the dislocation between both leaflets at the area of coaptation. These criteria proved useful. Because of the similarity in appearance, it may be helpful in the assessment of primary mitral valve prolapse. [ABSTRACT FROM PUBLISHER]

Regurgitant flow was analysed in 40 cases of mitral regurgitation, using combined ultrasonic pulsed Doppler technique and two dimensional echocardiography. Abnormal Doppler signals indicative of mitral regurgitant flow were detected in reference to the two dimensional image of the long axis view of the heart and the short axis view at the level of the mitral orifice. The overall direction of regurgitant flow into the left atrium was clearly seen in 28 of 40 cases, and the localisation of regurgitant flow in the mitral orifice in 38 cases. In cases with mitral valve prolapse of the anterior leaflet or posterior leaflet the regurgitant flow was directed posteriorly or anteriorly, respectively. The prolapse occurred at the anterolateral commissure or posteromedial commissure and resulted in regurgitant flow located near the anterolateral commissure or posteromedial commissure of the mitral orifice, respectively. In cases with rheumatic mitral regurgitation the regurgitant flow is usually towards the central portion of the left atrium and is sited in the mid-part of the orifice. The Doppler findings were consistent with left ventriculography and surgical findings. The ultrasonic pulsed Doppler technique combined with two dimensional echocardiography is useful for non-invasive analysis and preoperative assessment of mitral regurgitation. [ABSTRACT FROM PUBLISHER]

Japan’s toilets are generally ventilated 15 times per hour. Despite the development in toilets, the ventilation frequency in toilets has not been changed in recent times. Therefore, there is a possibility that toilets are being excessively ventilated. Reducing the ventilation frequency increases the return air to the heat exchanger and improves the efficiency of the heat exchanger. For an optimal ventilation frequency, we introduce a system that could control the exhaust air using sensors. The primary issue is the odor caused by reducing the ventilation frequency. In this study, we aim to eliminate the odor as quickly as possible by providing an exhaust port at the bottom of the wall (hereinafter referred as “baseboard deodorization”). First, we examined the relationship among the odor sensor, human’s olfactory odor identification and ventilation volumes with the toilet in operation to verify the usefulness of the sensors. Next, the air environment was analyzed using computational fluid dynamics (CFD). The results of the measurements and questionnaire survey indicate a correlation between the degree of contamination in the air and the odor intensity. The CFD analyses demonstrated, even after the frequency of ventilation reduced to 5 times per hour, that the ammonia concentration obtained was equivalent to 15 times per hour. To solve the odor problem due to the ventilation reduction, it is important to evacuate air immediately after the odor is generated. Among others, it was observed that a baseboard deodorization system contributes significantly to the reduction in ammonia concentration.

The “Strategic Energy Plan” implemented by the Cabinet of Japan in 2014 strives for zero energy building design for typical new construction by 2030. The present study focuses on a ductless and variable air conditioning system, using the Coanda effect, with the aim of reducing fan power, and saving of resources by reducing the space between the ceiling. In this study, we examined the air blowing method and evaluated thermal comfort using computational fluid dynamics as well as subjective perception of coolness in a midsize office. A draft zone was reduced by extending the interval between conditioned air outlets. However, if the extension of throw length was excessive, hot space would be formed near the air outlets, and there would be a risk of impacting thermal comfort. Moreover, we confirmed that the thermal comfort was generally favourable. In particular, perceived thermal comfort was better at the position in the office where the air flow landed on the upper body of the subjects. On the other hand, it decreased when the influence of the air flow was small, and at the point where air flow landed on the lower body of the subjects.

In this study, we propose a ductless air conditioning system using the Coanda Effect for a medium size office building to achieve a net-zero energy building (ZEB). The indoor temperature environment and air flow characteristics during cooling and heating conditions created by this system were evaluated. In addition, to validate the computational fluid dynamics (CFD) analysis results when the heating system was activated, the results were compared with the measurement results. The investigation indicated that for cooling, a good thermal environment could be established in the residential area; however, local draught continued to be an issue. For heating, it was confirmed that heating of the residential area could be accomplished using floor suction. In addition, it was shown that the accuracy of the CFD analytical results can be improved by adjusting the input conditions to the actual conditions.