Fourth Interval Research Articles

Coronary heart disease mortality in the Western Collaborative Group Study. Follow-up experience of 22 years.

In 1960-1961, 3,154 healthy, middle-aged men were entered into the Western Collaborative Group Study, a long-term study of coronary heart disease. A 22-year mortality follow-up of this cohort in 1982-1983 accounted for almost 99% of the cohort, and determined that 214 of the men had died of coronary heart disease. The risk of coronary heart disease mortality was studied for several variables measured at baseline, i.e., Type A/B behavior, systolic blood pressure, serum cholesterol level, cigarette smoking status, and age. Using a proportional hazards regression model, systolic blood pressure, serum cholesterol level, cigarette smoking status, and age were highly significant predictors (p less than 0.001) of 22-year coronary heart disease mortality. Type A/B behavior showed no association with 22-year coronary heart disease mortality (standardized relative hazard (SRH) = 0.98, 95% confidence interval (CI) = 0.85-1.12). Systolic blood pressure, serum cholesterol, and age showed relatively consistent positive associations with coronary heart disease mortality over four successive time intervals after the baseline examination. Cigarette smoking showed a significant positive association in the first and second intervals and a nonsignificant positive association in the third and fourth intervals. Type A/B behavior was positively but not significantly associated with coronary heart disease in the first and third intervals, significantly negatively associated (SRH = 0.70, 95% CI = 0.53-0.93) in the second interval and not associated in the fourth interval. The results confirm the importance of the traditional coronary heart disease risk factors, and raise a substantial question about the importance of Type A/B behavior as a risk factor for coronary heart disease mortality.

Quadratic integrals of the equations of motion of a rigid body in a liquid

General integrable cases of the Kirchhoff-Clebsch equations /1, 2/, with a fourth quadratic interval not explicitly dependent on time, are considered. A proof is presented of Steklov's theorem /3/ that the four cases pointed out by Clebsch /2/, Steklov /3/ and Lyapunov /4/ are the only ones for which the equations of inertial motion of a body in a liquid admit of a fourth quadratic integral. An analysis is presented of Lyapunov's statement /4/ that his integrable case may be considered as a limiting case of Steklov's, and Clebsch's third case as a limiting case of his second. It is shown that the fourth integral of the Kirchhoff-Clebsch equations pointed out by Kolosov /6/ does not lead to integrable cases other than those of Steklov and Lyapunov. In recent years, reports have been published concerning the “discovery” of new integrable cases of the equations of motion of a charged body in a magnetic field, which are isomorphic to the Kirchhoff-Clebsch equations; this runs counter to Steklov's theorem. This prompted the author to undertake an analysis of Steklov's original account /3/, which entirely vindicates the letter's theorem.

Ages of subsurface stratigraphic intervals in the Quaternary of Enewetak Atoll, Marshall Islands

Drill cores of Enewetak Atoll, Marshall Islands, reveal six stratigraphic intervals, numbered in downward sequence, which represent vertical coral growth during Quaternary interglaciations. Radiocarbon dates indicate that the Holocene sea transgressed the emergent reef platform by about 8000 yr B.P. The reef grew rapidly upward (about 5 to 10 mm/yr) until about 6500 yr B.P. Afterward vertical growth slowed to about 0.5 mm/yr, then lateral development became dominant during the last several thousand years. The second interval is dated at 131,000 ± 3000 yr B.P. by uranium series. This unit correlates with oxygen-isotope substage 5e and with terrace VIIa of Huon Peninsula, New Guinea, and of Main Reef-2 terrace at Atauro Island. The third interval is not dated because corals were recrystallized and it is tentatively correlated with either oxygen-isotope stages 7 or 9. The age of the fourth interval is estimated at 454,000 ± 100,000 yr B.P. from measured 234U 238U activity ratios. This unit is correlated with either oxygen-isotope stage 9, 11, or 13.

Age and marital status at first birth and the pace of subsequent fertility

Taking care to minimize the truncation bias inherent in cross-sectional data and controlling for other variables, this paper demonstrates the strong effects of both age and marital status at first birth on the pace of subsequent fertility. These effects are particularly strong in the interval immediately following the first birth but persist even into the fourth interval. Important differences are found with respect to the experience of rapid fertility, rather than in the mean lengths of intervals. These results add to the growing attention to the social dimensions of age as a variable in fertility processes.

Attenuation of ethanol intake by contingent punishment of food-maintained responding

Two food-deprived rats responded under a concurrent fixed-ratio 12 (food) fixed-ratio 1 (8% ethanol) reinforcement schedule in which a tone occurred during every second or every fourth interpellet interval. When ethanol-maintained lever presses during the presence of the tone shifted the food schedule to one in which electric shock punishment occurred, ethanol-maintained responding consistently decreased. The decrease in the frequency of ethanol-maintained responding varied directly with shock voltage from 25 to 100 V, and occurred during intervals with the tone present and absent. These results indicate that ethanol in take may be attenuated by contingent changes in a concurrent food schedule.

Use of Life Tables in Analysing the Dynamics of Copepod Populations

The population parameters have been characterized for the generations that developed during a complete reproduction year of a population of the calanoid copepod Diaptomus calvipes Schacht. A model is presented to calculate the numbers of each of the various instars of a copepod produced during any previous interval of time. Life tables were constructed from laboratory data and for the five generations of the 1971 field population as an aid in studying the population dynamics. Successful reproduction in the field population occurred from mid—March until mid—October. Development time increased for successive instars of the same generation. All generations had similarly shaped survivorship curves and there was a progressively lower rate of survival in successive generations. This lower survival rate was related to decreasing survival during the early naupliar stages. Survivorship of adults was characterized by a rectangular curve. Greatest mortality rates occurred during the egg to fourth naupliar interval (N—IV) and in the sixth naupliar stage (N—VI). Critical controlling factors in this population appear to be those which affect either survivorship in the interval between egg and N—IV or reproductive activity of adults.

On the influence of the initial row impact parameter and the row periodicity on an ion's dechannelling

Abstract Results are presented of computer simulations of light ion channelling in crystals which indicate four intervals of initial row impact parameters governing the dechannelling behaviour. The first (smallest impact parameters) causes 90% to 100% dechannelling in the collision with the first row, the second causes dechannelling in collisions with subsequent rows mainly due to the periodicity of the row potential, the third similarly due to subsequent collisions mainly due to thermal vibrations, and the fourth interval, associated with largest impact parameters, is the domain of electron multiple scattering.

An Investigation of the Curl-Down Test as a Measure of Abdominal Strength

Abstract Sixty freshmen college women were given the 30-second and 60-second curl-down tests and two trials on the Elgin Multiple Angle testing unit. Standing and sitting height and weight measurements were also recorded. Analysis of the data showed (a) no significant relationship of the curl-down scores to the physical dimensions, (b) a .78 reliability coefficient on the 30-second tests, (c) dynamometer scores positively related (r=.44 and r=.32) to the 30-second and 60-second scores respectively. A test between the correlated r's resulted in a significant t of 3.46 and a significant t (8.47) between correlated means on the split halves of the 60-second test. The 60-second test was given to another 72 subjects with scores recorded each 10 seconds. After the fourth 10-seconds interval, the scores radically decreased, therefore a 40-second curl-down test is recommended.

Growth, Molting Frequency, Heart Beat, Number of Eggs, and Incubation Time in Gammarus Zaddachi Exposed To Different Environments

Gammarus zaddachi from the Kleiner Kiel, Kiel, North Germany, were exposed to different temperature and salinity conditions in the laboratory and the rates of some life processes measured. All tests were performed under standard conditions (food, light, amount of water per individual, quality of water). The rates of growth, molting, heart beat, egg production and embryonic development proved to be similar in the same environment to those of the previously tested G. salinus (Kinne, 1960) from the same habitat. G. zaddachi and G. salinus, however, differ considerably with respect to these rate functions from a third Gammarus species of the Kleiner Kiel, namely G. duebeni. The latter exhibits much slower rates under the same conditions (Kinne, 1952b; 1953a, b). The intervals between subsequent molts are longer in G. zaddachi males than in females. No significant differences were observed in specimens exposed to the salinity levels 5‰, 10‰ and 30‰, respectively. Females kept without males tend to prolong progressively the molting intervals, beginning with the third or fourth interval after isolation. No relationship between body length and rate of heart beat could be established in 17 to 21 mm long males or in 14 to 16 mm long females. Such a relationship does, however, exist over a wider range of body length: the rate of heart contractions is definitely higher in immature specimens of a length of 5 to 6 mm. No significant differences of rates of heart beat in mature specimens were observed in 5‰ or 10‰. The number of marsupium eggs per female of a given length depends on the temperature, being higher at 14° to 16°C than at 18° to 20°C, and on the salinity. There exists a linear relationship between the number of eggs and the volume (cubed length) of the mother animal, except in senile females. In the absence of a male, there is a tendency to reduce progressively the number of eggs laid. A normal number of eggs is usually deposited only subsequent to a transfer of sperm. Along with the functional similarity between G. zaddachi and G. salinus there exists a striking structural similarity (Spooner, 1947; SegerstrAle, 1947; Kinne, 1954, etc.). The information available suggests that G. zaddachi and G. salinus represent two relatively young species which have only recently become genetically independent from each other (see also Spooner, 1947, 1951; and Kinne, 1954). The differences between these two species become apparent in terms of their distribution, ecology and interspecific sterility (Spooner, 1947; SegerstrAle, 1947; Steen, 1951; Kinne, 1954; Forsman, 1956) rather than in terms of the rate functions or morphological expressions studied. The physiological data available at this time are not sufficient for a detailed analysis. More elaborate experiments on the physiological potentialities of G. zaddachi and G. salinus may lead to the discovery of delicate differences and to a better understanding of their ecology and evolution.

Classical and Christian Ideas of World Harmony: Prolegomena to an Interpretation of the Word “Stimmung” (Part II)

In discussing the idea of musical World Harmony we have had occasion to mention the tetrachord and the fourth (interval) in their symbolic or allegoric impact. The number 4 is a constitutive element in Pythagorean cosmology since the speculations on the “well-tempered” state—of the soul, of the body, or of the universe itself—rest on the harmonious combination of four elements.

The Long-Period Variations in the Length of the 11-Year Solar Period, and Concurrent Variations in Terrestrial Phenomena

Synopsis Long-period variations in solar phenomena are shown by the relative numbers at epochs of maxima and the intervals between successive maxima or minima. Intensity values are available only from 1750, or the date of the beginning of the Wolfer relative numbers. The interval values are derived from the Wolfer epochs from 1611 and from the epochs of maxima beginning 301 A.D., first derived by Fritz and revised by the writer. There is a high negative correlation between the intensity at a maximum and the interval from the preceding minimum. The epochs of maximum and minimum auroral frequency, available since 1611, and of magnetic declination range since 1775, afford an independent check on the reliability of the Wolfer epochs. A change in two of the epochs of maxima is suggested. The reliability of the Fritz ancient epochs is confirmed by a graphical device, showing the continuity of the 11-year epochs since 301. The existence of long-period variations in the length of the 11-year period is shown by a graphical periodicity tabulation of the 11-year intervals since 301. A 37-year period is shown by the existence of maxima every third or fourth interval, and an 83-year period is shown by a similar tabulation of the smoothed intervals. These periods are also obtained by the rigid method of self-correlation of the 11-year intervals, and numerous series of terrestrial data yield by self-correlation the same periods. The meteorological effects following certain solar changes are briefly summarized.

Roman York: a Recent Discovery

IN the course of carrying out a municipal scheme of improvement, further remains of the fortifications of Roman York have been brought to light, which, it would appear, are part of the curtain wall erected by the emperor Constantinus Chlorus in the fourth century to strengthen the fortifications of the city against the attacks of pirates coming up the river (The Times, July 11). In driving an arcade through Coney Street, the remains of an internal tower were discovered which was built astride the wall, and was not external as towers previously revealed had proved to be. Its walls are of dressed stone, and on the south side stand to a height of nearly four feet. On the north side are the remains of what would appear to be a pier of dressed stone, three feet high and connected with the main wall by layers of stone slabs. This is believed to have been either the support of a platform of the tower, or the pier of a bridge, carrying the rampart walk over the interval formed by the tower. Remains of the cobbled rampart walk, with the foundations of another building on the east side, have been found. The position of the tower corresponds with what has hitherto been believed to be the character of the curtain wall, where it ran from the Multangular Tower to the angle tower at the south-east corner of the junction of Coney Street and Market Street. It is the fourth interval tower that has been found.