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An operation to enlarge the right ventricular cavity by placing a two-layer patch in the outflow of the right ventricle was evaluated in 9 puppies and 2 adult dogs. Autologous pericardium and Dacron fabric were sutured to the endocardium and epicardium, respectively, with a space left between. During follow-up to 22 months, right ventricle maximum pressure response was evaluated on acute pulmonary occlusion, angiography, treadmill exercise, and pathology. Postoperative hemodynamics were considered excellent, although residual dye in the right ventricle after each beat was seen on angiography. All animals completed the exercise tests without difficulty. The right ventricle pressure responses were the same in the study dogs as in the 4 normal control dogs. Shrinkage of the pericardial patch was notable, and inflow and outflow epicardial Dacron patches decreased in area by 40 and 12 per cent, respectively. Inflow patches showed greater inflammatory responses histologically. This study indicated that this operation is applicable without a gross disturbance in right ventricular function.

Changes in skin resistance and beat-by-beat heart rate, derived from the EKG, were obtained from the same pair of dry silver electrodes applied to the finger tips. The electronic criteria to be satisfied for application of this technique are discussed. The recording system was constructed using low-cost, solid-state circuitry. A typical record of changes in skin resistance and beat-by-beat heart rate is presented to demonstrate the performance characteristics of the equipment.

Sinus node re-entry (SNR) usually appears as a single beat. Tachycardias (SNRT) consistent with sustained SNR were seen in six patients and were initiated by premature stimulation of the high right atrium (six patients) and coronary sinus (four patients), and after continuous pacing from the high right atrium (four patients) or right ventricle (one patient) at rates of 130 to 200 per minute. During SNRT: (1) atrial beats exhibited a high-to-low atrial activation sequence, (2) the P-waves were similar in morphology to P-waves during sinus rhythm, and (3) re-entry in the A-V node or at the site of stimulation could be excluded. The cycle length of SNRT ranged from 625 to 320 msec. and SNRT either terminated spontaneously (six patients) or after premature atrial capture and/or vagal maneuvers (two patients). The electrophysiologic characteristics of SNRT and differentiation of SNRT from A-V nodal re-entry are discussed.

Optimal beat configurations to minimize response time to calls for service can be determined for a given number of police patrol beats during a shift. However, optimal manpower scheduling requires that the number of units vary by day of week. A variable beat design strategy is administratively infeasible. This model operates under a fixed beat design strategy and assigns beats to a variable number of units. The computer program improves an initial beat assignment by considering all possibilities of moving or sharing beats with other units. The new beat assignments are reevaluated till an optima is reached.

The recently developed experimental model for sinus nodal reentry was used to assess the effect of quinidine in 20 dogs. Sinus nodal reentry was demonstrated in 19 dogs and was abolished in all dogs when plasma levels of quinidine (average 4.8 mg/liter) were in the therapeutic range after an average infusion time of 7 minutes. Characteristically in 15 dogs, quinidine increased atrial refractoriness and slowed atrial conduction so that the arrival time of the atrial premature beat (A2) in the region of the sinus node fell outside the reentry zone and sinus nodal reentry was terminated. Conduction delay along the reentrant pathway preceded loss of sinus nodal reentry in 6 of these 15 dogs, thereby suggesting that quinidine-induced conduction delay and block along the reentrant pathway may be another mechanism for abolishing sinus nodal reentry. In the four remaining dogs in which sinus nodal reentry was abolished when the premature beat continued to fall within the reentry zone, the latter mechanism seems likely.

The normal heart period in the adults of Corethra plumicornis consists of a forward pulsation phase and a subsequent somewhat shorter backward beat phase followed by a pause of some seconds. The Q 10 s for the heart rate between 24 and 14·5°C are approximately 2·2 for both the forward and backward pulsation rates. The Q 10 s for the inverse of the forward phase length and for the inverse of the backward phase length are on average 1·55 and 1·08, the difference being statistically significant. This is also reflected in the percentage of time during which the forward beat occurs at each temperature. This is 60·0 per cent at 24°C and 67·0 per cent at 14·5°C. The results suggest that the pacemaker controlling the forward pulsation is more sensitive to a temperature change or to its indirect effects than the pacemaker controlling the backward pulsation.

Quin deserves recognition as a stage manager in Londons patent theatres between 1725 and 1751 because he compensated for John Rich's indifference to legitimate plays and for Charles Fleetwood's gentlemanly incompetence. As in his acting, Quin was adamantly dedicated to maintaining the established Augustan ideal.

Complete heart block implies an absolute independence between atria and ventricles that does not in fact always exist. Segers showed that, after complete block was artificially produced in the frog's heart, atria and ventricles would sometimes begin to beat exactly in phase, most commonly in a 2 to 1 ratio. He subsequently reported one clinical example of 2 to 1 A-V synchronization in a patient with complete heart block. Two further cases that may illustrate different varieties of synchronization are here presented.

1. 1. External defibrillation was attempted in experiments on forty-one dogs. In all instances the heart could be readily defibrillated, as indicated by the electrocardiogram. However, a return of pulse and blood pressure seldom occurred beyond a fifty-second time limit. 2. 2. In experiments on seventy dogs the heart was permitted to fibrillate for 120 seconds before a countershock was directly applied. Electrical defibrillation promptly occurred but there was no return of systemic blood pressure. Following immediate massage there was a quick return of a coordinated beat and a normal blood pressure. 3. 3. In experiments on eighty-three dogs the heart was allowed to fibrillate for 120 seconds; then ventilation and massage were instituted before a direct countershock was applied to the ventricles. This was followed in each case by normal circulation and eighty-three survivals. 4. 4. For successful cardiac resuscitation, the re-establishment of the oxygen system is the primary act and the restoration of the heart beat is secondary. 5. 5. It appears that it is a minor problem to defibrillate the heart through an intact chest. However, to restore the life functions of an animal after some fifty seconds, supplemental measures have to be taken such as cardiac massage, or intra-arterial transfusion or infusion. 6. 6. Under ideal circumstances, when a trained team and equipment are in readiness in a room, a few seconds spent on external countershocking might be conceivable. We are carrying out additional studies continuously.

The influence of various medicaments upon the heart has been widely studied. The earlier experiments for the most part dealt with the hearts of adult animals. So far as we are aware few similar studies have been made on the embryonic heart. It seemed desirable, therefore, to make such a study, using adrenaline as the test substance. During the course of our studies Doctor Tuji of Kioto published the results of a similar investigation which were not, however, entirely in accordance with ours. We have studied the action of adrenaline on the embryonic chick heart and on strip preparations of it at different stages of development. The hearts were removed, kept in warm Ringer’s solution and tested in the same solution. The first appearance of automatic movements in the embryonic chick heart: Since the time of Aristotle the beat of the embryonic chick heart has frequently been observed. The period at which this is first evident, however, has been quite differently reported by different observers. Harvey noted t...

SUMMARY 1 The nymph of Chloeon dipterum is a pelagic animal living in ponds, Its plate-like bilamellate gills are described. 2 By means of metachronal rhythmical movements of the gills, in which members of pairs beat synchronously, currents of water are set up over the body. These currents which are on the whole axial to the body explose water from all regions surrounding the body. 3 The gill and abdominal musculature is described and it is shown that a modification of normal musculature has occurred to provide direct muscles to the gill bases and also to make possible the habit of swimming by rhythmical movements of the abdomen rather than by limbs. These movements are lateral and are made about a vertical axis. Swimming is always preceded by a vigorous up and down movement of the caudal filaments. This movemelit about a transverse axis as in the tail flukes of a whale is then abandoned as the side to side movements of the abdomen take charge, when the animal swims aa does a fish.

One wonders if much of the looseness in speech, morals, dress, and conduct that characterizes the modern age is not directly traceable to the degradation of one of the fine arts, a universal art-music. Consider the popular music of today. It consists chiefly of ragtime and jazz. Music and dancing are so closely allied that the degradation of the one means the degradation of the other. Jazz music means jazz dancing. It is difficult to say which precedes in the process of degeneration. In all probability the two move downward together. Jazz dancing means the taking of liberties. Any inclination of the dancer to be bold and reckless is increased by the noisy, wild, simple beat, beat of the tantalizing music designed to appeal purely to the physical. The natural accompaniments of jazz dancing are slang, immodest dress, and a general lowering of moral standards.

A heart ratemeter operating over a range of 30–900 beats per minute has been designed. The device is triggered from any measured cardiac variable to produce a linear d.c. beat-by-beat readout. The cardiac frequency is found by a true reciprocal computing process provided by a variable-slope ramp generator operating on the period between beats. This computer, and other circuitry within the ratemeter, uses low-cost operational amplifiers to simplify the design and construction.

The microvibration or minor tremor (MT) on the body surface of man and rabbit was recorded under various physiological conditions. The electrocardiogram (EKG) or heart beat and sometimes electroencephalogram (EEG) were also traced simultaneously with the recording of MT to elucidate the physiological significance of the mechanism of the development of MT. In some cases, correlation and frequency analyses were performed on MT to obtain their average time-and frequency-patterns.In MT tracings under the relaxed condition, two groups of vibrations corresponding to the first and second heart beats or the R and T waves of EKG were observed. This synchronization was more evident in the crosscorrelogram of the heart beat or EKG and the MT than in the original MT tracing. In the autocorrelograms of MT, a damping of oscillation with a beat phenomenon was clearly shown.In the power spectra of the autocorrelograms, several peaks were recognized in the so-called alpha frequency which confirm the beat oscillation in the autocorrelograms.However, its frequency range was often broader than that of the alpha wave in EEG.Even when the radial pulse was suppressed by pressure on the upper arm, the two groups of main vibrations appeared which corresponded to the R and T waves of EKG.This finding suggests that these vibrations are not closely related with the pulse wave and/or other vibrations of the artery caused by the blood flow, but rather related to vibration of the body surface due to the heart beat.During sleep and in the awake state, in which the inhibition and acceleration of MT were observed respectively, the same correspondence between MT and EKG as that in the relaxed was also demonstrated.It was suggested from the above results that the regulating system of the heart beat in addition to so-called muscle tonus might also play an important role in the inhibition and acceleration of MT under various physiological conditions.A part of this (or rabbit) research reported in this document has been made possible through the support and sponsorship (DA-92-557-FEC-35764) of the U. S. Department of Army, through its Far East Research Office. The authors thank sincerely to Dr. Z. KIYASU, K. IBUKI and T. KIMURA for applying the computer MI-B.

Owing to the indirectness of the methods hitherto used for estimating the quantity of blood pumped out from the left ventricle at each systole, this important factor in all calculations of the work done by the heart has never been satisfactorily determined. Of the later physiologists who have investigated the subject, Volkmann and afterwards Vierordt, from calculations based upon the mean velocity of the stream of blood in the unbranched aorta, obtained the fraction 1/100 as representing the ratio of the average weight of blood ejected at each systole of the left ventricle to the weight of the whole body. Fick, from data obtained by placing the arm in a plethysmograph, and estimating the velocity of the stream of blood in the axillary artery from the increase in volume of the whole arm at each systole of the heart, arrived at a much smaller fraction, about 1/1000 for the ratio between the weight of blood thrown out at each systole and the body weight.

Measurements were made of heart rate, aortic blood pressure, systolic ejection period/beat, myocardial blood flow, and myocardial oxygen consumption in nine normal young men during three bouts of upright bicycle exercise: 1) at the workload which produced a heart rate of 120 beats/minute, 2) at the higher workload necessary to produce a heart rate of 120 beats/minute after administration of intravenous propranolol 0.25 mg/kg, and 3) with infusion of propranolol, at the same workload as the first exercise bout. Comparing exercises 1 and 2, we found a much higher workload was required to produce the same heart rate after propranolol. The blood pressure, heart rate-blood pressure product, and myocardial oxygen consumption were the same despite the much greater level of exertion. Comparing exercises 1 and 3, the heart rate, blood pressure, heart rate-blood pressure product, and myocardial oxygen consumption were all significantly lower during exercise 3 after propranolol despite the fact that the same degree of exercise was being done. As in previous studies, the heart rate-blood pressure product was an excellent correlate of myocardial oxygen consumption despite the change in contractility induced by propranolol. The systolic ejection period was prolonged significantly altering the tension-time index (TTI), which became an inadequate index of myocardial oxygen consumption. It is concluded that the heart rate-blood pressure product is a good index of myocardial metabolic needs during exercise and the relationship is undistorted by marked changes in contractility, but the tension-time index is a poor correlate. This data emphasizes the fact that the relative metabolic loads for the whole body and for the heart are determined separately and may not change in parallel with a given intervention.

Transection experiments of hearts in male and female house flies, Musca domestica L., indicate that there are at least 11 regions in the female and 10 in the male that can beat for extended periods. The beat does not appear to be contingent upon the alary muscles, heart continuity, size of heart segments, or heart symmetry, and evidences no constant starting point in the intact heart.

By depressing the A-V conduction system with procain-amide, the retrograde impulse of the ventricular extrasystole was sometimes blocked or followed by a reciprocal beat. The relation between the coupling time and the kinds of extrasystoles was examined. The retrograde conduction time of the ventricular extrasystoles with reciprocal beats had negative correlation with the coupling time and the antegrade conduction time of the reciprocal beat. Similar relations were found in the experiments of the reversed reciprocal rhythm, although it was far more difficult to produce this arrhythmia under the sinus rhythm.

slight pitch deviations readily. Since music teachers often have explained intonation chiefly through the use of electronic devices, which indicate pitch imperfections visually rather than aurally, many students have not been trained adequately in aural pitch apperception.l In the late 1950s, Leeder and Haynie, followed later by other music educators, began to advocate teaching a tuning procedure long used by piano tuners, physicists, and some musicians.2 The procedure, called the beat elimination process, is a dependable aural method of achieving correct intonation.3 The paucity of references in the literature to the pedagogical use of the beat elimination process suggests that this procedure is little known and seldom employed in music education.

This study was designed to investigate selected spatial and temporal characteristics of movement. Forty-one subjects were administered the rhythm test of the Drake Musical Aptitude Tests. From the resulting distribution of scores, 10 subjects with a high level and 10 subjects with a low level of rhythmic ability were filmed while performing a simple rhythmic movement task. The task, done to a fixed metronomic rate of 66 beats/minute, consisted of a forward lunge in which the arm was swung forward and upward until the hand was directly in line with a target. The subject had to stop the motion of her arm in such a position that her hand was in line with the target on every other beat of the metronome, and recover to a starting position on the alternate beats. The subjects responded to eight beats while standing in place and to eight while responding in the described manner. The movement task was recorded on film; deviations in the time and space at the moment of the stimulus were estimated in a fra...

A chronograph is described for recording continuously the rates of many different kinds of rhythmic processes over long time periods. The rate is read directly from the length of a line of ink, drawn by a moving pen. Rates of beat of excised turtle's hearts in Ringer's solution have been recorded at 25°C. under constant conditions of temperature, pH, and oxygen supply for periods of 36 hours. Regular periodic variations in the fundamental rhythm are figured, as well as rates of extraordinary constancy. The effects of adrenalin, ephedrin, thyroxin, α and ß pituitary hormone insulin, nicotin, and atropin are described in the text.

An anomalous effect of respiration on the arterial pulse has been found in several patients with severe left heart failure. In contrast to the behavior of the pulse in normals in which the pulse beat becomes stronger in expiration, in these cases the strong beats occurred in inspiration. In two of the cardiac patients the pattern reverted to normal with clinical improvement.

1. Electrophysiological techniques have been used to define pacemaker characteristics and organization in the heart of the tunicate Ciona intestinalis . The frequency of spontaneous beat initiation was regular or irregular for a given period of time; in any single heart, these frequency modes intermittently changed from one to the other in no regular order. Reversals could take place immediately, after a pause, or after collisions. 2. Trains of electrical stimuli applied to the ends of the heart could drive propagated contractions at a frequency of up to 2.6/sec, and dominance could be controlled by altering the frequency and/or intensity of the stimuli. Each end gave a characteristic response to increasing frequency of driving, and the threshold for one-to-one driving was frequency-dependent. 3. When the middle of a heart was ligatured, the two ends were independently active. Visceral ends exhibited regularly varying levels of high and low frequency with a period of several minutes, whereas the frequency levels of the hypobranchial ends varied irregularly. 4. Intracellular resting potentials were approximately -50 mV., and propagated action potentials associated with contractile events did not show ‘overshoot.’ Partial electrical responses were affiliated with weak or failing mechanical events, and complex, double-peaked intracellular potentials were often associated with collisions. In some cases a cell could show electrical activity that was completely dissociated from the mechanical response of the whole heart. Excitation thus probably spreads passively between cells, and multiple foci of activity may co-exist at any given time. 5. From electrophysiological and anatomical data, an hypothesis is proposed to explain the observed mechanical activity on the basis of the interactions of individual cells and higher-order interactions among groups of cells. Supported by grants from the U.S. Public Health Service (NB-02944) and the U.S. Air Force Office of Scientific Research (AFOSR-334-67) to Dr Donald Kennedy, and by a National Science Foundation Pre-doctoral Fellowship to the author.

In the present investigations, we have proposed, using the last-ing preparations of the denervated heart of dogs deprived of the su-prarenal medullae, to determine on sustained administration for two minutes, the minimal effective dose of adrenaline for causing the dener-vated heart to beat faster, as well as the threshold value for elevating the blood pressure under normal, quiet conditions of animals. The minimal effective dose of adrenaline for accelerating the heart is in the vicinity of 0.0002-0.0003 mgrm. per kilo per minute. Al-most the same dose was found as the threshold value for the blood pressure. And this minimal effective dose of adrenaline on sustained administration is five times or more as great as the quiet rate of the epinephrine discharge from the suprarenal bodies.

A simple and inexpensive method of obtaining a photographic record of pulse beats by fixing a mirror over a vein or artery is described. Faults involved in other methods are avoided. By means of crossed slits a fine point of light traces out a curve which exhibits details of the pulse beat. It is hoped that these tracings will be of use for purposes of diagnosis in cases where the electrocardiograph is not available.

1. 1. Measurements of the external work and power of the left ventricle have been made in 19 subjects. Computations were based on instantaneous measurements of pressure, velocity, and flow in the ascending aorta. 2. 2. In 11 subjects without known cardiovascular disease the resting stroke work index ranged from 51 to 90 Gm.M./M.2 per beat. The average minute work index was 5.2 Kg.M./M.2 per minute in the same group. 3. 3. The administration of 1-norepinephrine produced not only a rise in the total work performed, but also a change in the temporal pattern of work accomplishment whereby the increase in power output was most pronounced during the latter half of the ejection period. 4. 4. In 6 individuals with nonvalvular heart disease but normal external work output, increases in external power during late systole, relative to the normal, were found. In 3 subjects with work values below 50 Gm.M./M.2 per beat, there was both a general diminution in the levels of power achieved and an altered pattern of work performance. 5. 5. The factors relating to the manner of work accomplishment by the intact ventricle have been discussed.

In the following article Mr. Dingwall shows how a social evil grew up among young people in Manchester and how police action was taken to combat it.

1. Physiological Aspects of Rhythmic Neural Activity. While recent studies have shed some light on the significance of the electrical activity of the nervous system, there has been no adequate explanation for the wave formation or synchronization of this electrical activity. Adrian (1) sums up the problem. "The origin of the 10-a-second rhythm is still uncertain, though the evidence points to some widespread organization, probably involving the central masses as well as the cortex. There are abundant nervous connexions for coordinating the beat, and w.hen the rhythm is well developed it is possible to record impulse discharges in phase with it passing to and fro in the nerve fibers of the white matter below the cortex. But in some areas no impulse could be detected entering or leaving the cell layers, though the potential waves keep more or less in step with those elsewhere. There is no proof that the waves are kept in phase by some means which does not involve nervous signalling, for impulses in axons of small diameter might well be missed, but it is not altogether unlikely that the synchronization is due in part to a direct electrical influence of one group of nerve cells on another. Gerard and Libet have shown that synchronization can occur between the two halves of a frog's brain cut in two and then placed in contact, and more recently Arvanitaki has shown that individual nerve cells may influence one another if they are brought close together in a conducting medium. At all events there are many examples of synchronized rhythmic activity in large collections of nerve-ormuscle cells. In the optic ganglion of the water beetle, for instance, there may be both a slow rhythm when the eye is in darkness and a rapid one when the eye is exposed to a bright light. The change from a slow to a fast rhythm is curiously reminiscent of that in the cerebral cortex when a sensory stimulus abolishes the 10-a-second rhythm and substitutes one at 40-60 a second. Such resemblances in preparations of quite different structures may be quite fortuitous, but they make it difficult to resist the suggestion that the rhythms of the brain may be dependent on the general properties of cell masses rather than on any special anatomical arrangement of them. Whatever its origin, the 10-a-second rhythm of the cortex corresponds to the resting, drowsy, or inattentive state and there is no such uniform pulsation when the brain is alert." Adrian's claim that "There is no proof that the waves are kept in phase by some means which does not involve nervous signalling" w^ould be difficult to maintain for certain slow waves in the light of the observations of Sloan and Jasper (38) on the mechanism of "spreading depression" in the cerebral cortex. The phenomenon of "spreading depression" they found, could enter an area of cortex completely isolated "by a circumscribed cortical incision extending through the cortex and down into the subjacent white matter for two or three mms.," as long as the surfaces of the incision are in contact. However, if the isolated area of cortex is insulated from the rest of the cortex, the spreading depression does not enter it. This indicates that, "Only physical and neural continguity are re42

The beat generation and its followers the beatniks have received considerable attention leading largely to the conclusion that the beat is a stubborn, perverse, and irresponsible person drunk on his own individuality, without a program of his own beyond revolt and livingit-up in following his own natural impulses. Many responsible critics point out how ridiculous and senseless the beat movement is and contend that society has no worry because a few individuals have gone astray, let society reject them and continue on its way. Do the critics imply that we should all be squares? Every pupil is beat! Not entirely, but to the extent that he does not learn to express his natural impulses within the range of sanctioned means of expression provided by our society. In the beginning of the socialization process the individual's urges to express his natural impulses clash with the demands and expectations of society, but, as a rule, the individual identifies with society and accepts its values, standards, and expectations as being adequate for self-realization. Ideally, the socialization process should be a compromise between the individual and society, with each being modified for the benefit of both. In the case of the extreme beat the individual tries to win out without accepting the social framework. In the case of the extreme square, society wins out, leaving the person as a depersonalized victim of a static society. Most pupils will be found between these two extremes, with the beat characteristic following the general pattern of the normal

An ultrasonic instrument was devised to aide accurate placement of the cardiac tube during the vertriculo-atrial shunt operation. The ultrasonic method was applied in 22 clinical cases in surgery and compared with the roentogenographic method and the endocardiac electrocardiographic method. The tricuspid valve echo was easily detected, because it has characteristic pulsating, polyspiky and shifting nature within an extent of 1 cm according to the cardiac beat. It was concluded from the comparative study that the roentogenographic method only gives silhouette, and the relationship between the probe tip and the vertebral body segment was almost inconsistent. Furthermore, the endocardiac electrocardiogram did not always show biphasic P wave and biphasic P wave was recorded at various distances ranging from 0 cm to 3.5 cm from the tricuspid valve. On the other hand, the ultrasonic method has the important advantages that the distance between the probe tip and the tricuspid valve can be measured directly and correctly, thus enabling operator to place the probe at any desired position in relation to the tricuspid valve.