Showing papers by "University of Hawaii published in 1985"
TL;DR: In this article, a comparative study of mtDNA and nuclear DNA variability is presented, with emphasis on mtDNA's uniparental and apparently haploid mode of inheritance, which makes mtDNA a superb tool for building trees and time scales relating molecular lineages at and below the species level.
Abstract: This essay reviews comparative studies of animal mitochondrial DNA (mtDNA), with emphasis on findings made and ideas developed at Berkeley. It argues that such studies are bringing together two previous paths of progress in evolutionary biology. One path is that of those who worked far above the species level and were concerned with genealogical trees, time scales and the accumulation of new mutations on surviving molecular lineages. The other path is that of those who worked at and below the species level and were concerned mainly with population structure, migration and the frequencies of alleles that existed in an ancestral population. This fusion of paths is made possible by the high rate at which mutations accumulate on mtDNA lineages and by this molecule's uniparental and apparently haploid mode of inheritance. These properties make mtDNA a superb tool for building trees and time scales relating molecular lineages at and below the species level. In addition, owing to its mode of inheritance, mtDNA is more sensitive to bottlenecks in population size and to population subdivision than are nuclear genes. Joint comparative studies of both mtDNA and nuclear DNA variability give us valuable insights into how effective population size has varied through time. Such studies also give insight into the conditions under which mtDNA from one species can colonize another species.
1,208 citations
Book•
01 Dec 1985TL;DR: In this article, the authors give readers conceptual and practical guidelines for dealing with the management of today's information systems function and present a framework that provides guidance for readers, using profiles of actual work as a key element of the overall learning process.
Abstract: From the Publisher:
This book gives readers conceptual and practical guidelines for dealing with the management of today's information systems function. The authors' objective is to capture the material of most current importance to information systems executives and organize it around a framework that provides guidance for readers. Updated throughout each chapter to reflect the latest techniques and technology available, the Fourth Edition continues to use profiles of actual work in today's companies as a key element of the overall learning process.
469 citations
TL;DR: It is suggested that obligate carrier mothers and daughters of intellectually normal transmitting males are rarely, if ever, mentally impaired and that the sibs of transmitting Males are much less likely to be retarded than the sIBs of mentally impaired males.
Abstract: A new series of 96 pedigrees with the fra(X) syndrome was analysed using complex segregation analysis with pointers, defining affection as any degree of mental impairment. These families were found to exhibit the same segregation pattern as the first series of 110 pedigrees (Sherman et al. 1984). The best estimate for penetrance of mental impairment in males was 79% and in females was 35% for the combined data. Again, there was little evidence for sporadic cases among affected males. Many more intellectually normal transmitting males have been observed since the existence of such males and the concomitant need to investigate the paternal side of pedigrees was recognized. On further investigation of all 206 pedigrees from the old and new data sets, the sibships of nonexpressing males appeared to be different from those of expressing males. Our analysis, using mental impairment as the phenotype, suggested that obligate carrier mothers and daughters of intellectually normal transmitting males are rarely, if ever, mentally impaired and that the sibs of transmitting males are much less likely to be retarded than the sibs of mentally impaired males. Though mothers and daughters of transmitting males are similar in phenotype, the expression of the gene in their offspring appears to be different: the penetrance of mental impairment is higher in offspring of intellectually normal daughters of transmitting males than in offspring of intellectually normal mothers of transmitting males. The implications of these observations for genetic counseling and for genetic models of the fra(X) syndrome are discussed.
467 citations
TL;DR: Estimated maternal age-specific rates of trisomy among all recognized pregnancies were calculated and suggest that a majority of oocytes of women aged 40 years and older may be aneuploid.
Abstract: The effect of maternal age on the incidence of chromosomally normal spontaneous abortion and different categories of chromosome abnormality among all clinically recognized human pregnancies was evaluated. The results provide no evidence for a significant association of age with sex chromosome monosomy or polyploidy, but clearly demonstrate an effect of age on the frequency of trisomy and chromosomally normal spontaneous abortions. Estimated maternal age-specific rates of trisomy among all recognized pregnancies were calculated and suggest that a majority of oocytes of women aged 40 years and older may be aneuploid.
456 citations
TL;DR: In this paper, a new class of seamounts consisting of horsts and diapirs of metamorphosed forearc material was identified. But the authors only considered the outer half of the Mariana forearc.
Abstract: Large seamounts occur on the outer half of the Mariana forearc. They represent a new class of seamounts consisting of horsts and diapirs of metamorphosed forearc material. The degree of metamorphism in this material depends on the amount of water available and the pressure-temperature regime of the forearc wedge. The major source for the water involved in the metamorphism is most likely the descending slab. Theoretical models for thermal regimes in convergent margins suggest that the lower grade metamorphic facies will be restricted to the outermost part of a forearc. Zeolite and chlorite facies rocks predominate in dredge hauls from horsts on the outer 50 km of the Mariana forearc. Thermal models indicate that higher grade greenschist facies should occur farther from the trench. Seamounts that were probably formed in response to diapiric emplacement of serpentinite predominate from 50 to 120 km from the trench. Uplift of the horsts and emplacement of the serpentinite diapirs were probably facilitated by vertical tectonic movement in response to subduction of plate seamounts and by fracturing of the Mariana forearc.
199 citations
TL;DR: The relative efficacy and attributes of the use of these systems to ascertain vital status are described, in part because of Social Security number discrepancies.
Abstract: Ascertainment of the vital status of individuals is of central importance to epidemiologic studies which monitor mortality as an end point. Utilizing identifying information collected in 1973-1974, the Hypertension Detection and Follow-up Program, a prospective, multicenter study, followed 25,362 individuals to determine eight-year mortality. In the most recent follow-up, there were 617 individuals whose vital status was not known. Available identifying information on these and on all 1,322 participants known to have died in 1979-1981 was submitted to the National Death Index (NDI) for possible confirmation of vital status. A subset of individuals who had Social Security numbers (490 lost to follow-up and 1,154 known deaths) was also submitted to the Social Security Administration (SSA). The NDI correctly identified 87.0% of the known deaths. Of the 1,154 known deaths (those with known Social Security numbers) submitted to both agencies, the NDI identified 93.1% and the SSA 83.6%. Significant variations by race and sex were noted in the identification rates, in part because of Social Security number discrepancies. False matches through the NDI matching process occurred for 10.4% of the known deaths. In the more restrictive SSA search, only 0.5% false matches resulted. For those lost to follow-up, vital status was ascertained in 57.1%. This paper describes the relative efficacy and attributes of the use of these systems to ascertain vital status.
199 citations
TL;DR: As part of an on-going longitudinal study, 7895 men of Japanese ancestry living on the island of Oahu, aged 45-68 and free of evidence of prior stroke at entry examination, have been followed by re-examinations and surveillance, there was an inverse relation between dietary fat intake and thrombo-embolic and total stroke incidence.
Abstract: As part of an on-going longitudinal study, 7895 men of Japanese ancestry living on the island of Oahu, aged 45-68 and free of evidence of prior stroke at entry examination, have been followed by re-examinations and surveillance. During ten years of follow-up 154 men developed thromboembolic stroke, 65 developed intracranial hemorrhage, and 19 developed stroke of unknown type. There were 79 deaths attributed to stroke. The independent risk factors for thrombo-embolic stroke were elevated blood pressure, glucose intolerance, age, electrocardiographic evidence of left ventricular hypertrophy or strain, cigarette smoking and proteinuria. Attributes associated with increased risk of intracranial hemorrhage were age, elevated blood pressure, cigarette smoking, serum uric acid and, inversely, serum cholesterol level. Electrocardiographic evidence of left ventricular hypertrophy or strain significantly increased the risk of cerebral hemorrhage, but was not associated with subarachnoid hemorrhage. In univariate analysis, there was an inverse relation between dietary fat intake and thrombo-embolic and total stroke incidence. An inverse relation was also shown between protein intake and total stroke incidence. These dietary relations became statistically not significant in multivariate analysis. No relation was found between salt intake and the incidence of stroke.
181 citations
TL;DR: Results from the two studies suggested that patients in both trials felt that the additional medical monitoring, the opportunity for a "second opinion," and the reassurance received were more important benefits than actual physical improvement.
174 citations
TL;DR: Results substantiate the hypothesis that disproportional food acquisition is the primary mechanism responsible for the size hierarchy effect and suggest Dominant-subordinate relationships, set up in the aquarium, appearresponsible for the disproportion food acquisition and thus mediate thesize hierarchy effect.
Abstract: Juvenile cichlids, Tilapia zillii, of equal initial standard length were randomly assigned to one of five treatments to assess the relative importance of individual physiological and activity differences, disproportional food consumption, and social interaction on growth depensation and mean growth. Results substantiate the hypothesis that disproportional food acquisition is the primary mechanism responsible for the size hierarchy effect. Individual physiological and activity differences played a negligible role in the phenomenon. Dominant-subordinate relationships, set up in the aquarium, appear responsible for the disproportional food acquisition and thus mediate the size hierarchy effect. Dominant fish ingest more food by either acquiring a limited ration first, preventing a subordinate's food acquisition, or behaviorally inhibiting a subordinate's feeding behavior.
166 citations
TL;DR: Reflectance spectra from several regional pyroclastic deposits are presented in support of the theory that mantling units have a unique spectral signature indicative of the presence of a significant, Fe-bearing volcanic glass component as mentioned in this paper.
TL;DR: Infertility in bitches immunized with PZP may be due to prevention of zzon penetration, because their antisera inhibited zona penetration of oocytes by spermatozoa in vitro, however, alterations in ovarian function preventing ovulation and luteinization could be involved in high-titered bitches.
Abstract: To determine the changes in patterns of 17 beta-estradiol and progesterone levels underlying abnormal cycles in bitches immunized with solubilized crude porcine zonae pellucidae (cPZP), to attempt to circumvent these problems by immunizing with a purified zona fraction (pPZP), and to test the effectiveness of different adjuvants, bitches were immunized with cPZP or pPZP 2-6 times with no adjuvant, Freund's adjuvant, alum adjuvant, or the adjuvant CP-20,961. The bitch immunized without adjuvant had a low titer with a normal cycle and fertility. Immunization with cPZP and adjuvant produced moderate to high titers of antizona antibodies and infertility. Bitches with high titers experienced abnormal estrous cycles. Estradiol rose during proestrus, but instead of falling sharply in early estrus as in controls, it remained elevated. Progesterone did not rise. The moderate-titered bitches had normal cycles and steroid patterns. Bitches immunized with pPZP had moderate titers. Cycles were normal after 3 injections, but after 6 injections one bitch had an abnormal cycle. One pPZP-immunized bitch remained fertile but the others were infertile. Alum was the mildest adjuvant, causing no injection site lesions, but the highest titers occurred with Freund's and CP-20,961 adjuvants. All three adjuvants induced titers sufficient to inhibit fertility. Infertility in bitches immunized with PZP may be due to prevention of zona penetration, because their antisera inhibited zona penetration of oocytes by spermatozoa in vitro. However, alterations in ovarian function preventing ovulation and luteinization could be involved in high-titered bitches.
TL;DR: It was found that, although the variance of the distribution decreases with increasing numbers of loci examined as expected, the shape of the Distribution may remain skewed or bimodal, and parametric statistical tests may not be valid for making comparisons among populations or species.
Abstract: Summary. -The distribution of mean heterozygosities under an infinite allele model with constant mutation rate was examined through simulation studies. It was found that, although the variance of the distribution decreases with increasing numbers of loci examined as expected, the shape of the distribution may remain skewed or bimodal. The distribution becomes symmetrical for increasing mean heterozygosity levels and numbers of loci. As a result, parametric statistical tests may not be valid for making comparisons among populations or species. Independent sample t-tests were examined in detail to determine the frequency of rejection of the null hypothesis when pairs of samples are drawn from populations with the same mean heterozygosity. Differing numbers of loci and levels of mean heterozygosity were examined. For mean heterozygosity levels above 7.5%, t-tests provide the proper rejection rate, with as few as five loci. When mean heterozygosity is as low as 2.5%, the t-test is conservative even when 40 loci are examined in each population. Independent sample t-tests were then examined for their power to detect true differences between populations as the degree of difference and number of loci vary. Although large differences can be found with high certainty, differences on the order of 5% heterozygosity may require that large numbers of loci (>40) be examined in order to be 80% or more certain of detecting them. In addition, it is emphasized that, for small numbers of loci (<25), the statistical detection of differences of interesting magnitude requires that relatively rare sampling events occur and that much larger differences be observed among the samples than exist for the population means. Two reasons exist for the lack of sensitivity of the test procedures. First, when mean heterozygosity levels are low, the non-normality of the sample means is perhaps most important. Second, even when mean heterozygosity levels are high or when sample sizes are large enough so sample means are approximately normally distributed, the intrinsically high interlocus variance of heterozygosity estimates makes the tests insensitive to the presence of heterozygosity differences that might be biologically meaningful. Finally, the implications of the results of this study are discussed with regard to observed low levels of correlation between heterozygosity and other explanatory variables.
TL;DR: Using a split-root technique, roots of soybean plants were divided between two pots and results indicated that VAM fungi did enhance N transfer from one plant to another.
Abstract: Using a split-root technique, roots of soybean plants were divided between two pots. In one of the two pots, two maize plants were grown and half of those pots were inoculated with the vesicular arbuscular mycorrhizal (VAM) fungus, Glomus fasciculatus. Fifty-two days after planting, 15N-labeled ammonium sulfate was applied to the pots which contained only soybean roots. Forty-eight hours after application, significantly higher values for atom per cent 15N excess were found in roots and leaves of VAM-infected maize plants as compared with the non-VAM-infected maize plants. Results indicated that VAM fungi did enhance N transfer from one plant to another.
TL;DR: The authors showed that violence does not occur between libertarian states, and that the more libertarian two states, the more likely two states are to be divided into two "no-fly zones".
Abstract: This article subjects the following propositions to systematic tests against the quantitative literature: that violence does not occur between libertarian states; that the more libertarian two stat...
TL;DR: In this article, the authors report progress of the Renewable Resources Research Laboratory on the conversion of biomass to olefins, and show that the degradation of glycerol in supercritical water results in the preferential formation of acetaldehyde.
TL;DR: It is indicated that eel sperm flagella, which at rest are straight, are induced to bend helicoidally by ATP, as the result of sliding between tubules that is blocked at both the base and tip of the organelle.
Abstract: The sperm flagella of the eel, Anguilla anguilla, are capable of vigorous motion in spite of having an axoneme with reduced structure that lacks the outer dynein arms, radial spokes and spoke heads, the two central tubules and the central tubule projections that are all part of the standard "9+2" axoneme. These sperm progress forward rapidly as a result of the propagation of helicoidal waves distally along the flagellum. Their flagellar beat frequencies are high, 93 Hz at 21 degrees C, and they roll at a frequency of about 19 Hz. Eel sperm could be demembranated with Nonidet P-40 and reactivated with MgATP2- in 0.22 M K acetate at pH 8.1. The reactivated motility closely resembles that of the live sperm, with a beat frequency of 69 Hz, but the demembranated flagella are unusually fragile, and commonly disintegrate by a combination of splitting, coiling, and sliding within a few minutes. Little reactivation is obtained if acetate is replaced by Cl- in the reactivating medium. The Michaelis constant for beat frequency (0.2 mM) is similar to that obtained for several "9+2" flagella. These sperm, however, appear to lack the mechanism by which Ca2+ regulates waveform. Our results indicate that eel sperm flagella, which at rest are straight, are induced to bend helicoidally by ATP, as the result of sliding between tubules that is blocked at both the base and tip of the organelle. The flagellar waveform consists of a series of planar bends separated by short regions of right-handed twist, which give it an overall left-handed helicoidal form.
TL;DR: Soybean rhizobia isolated from two soils with different cropping histories from Hubei province in central China showed significant cultivar-rhizobial interactions, and there was at least one fast-growing isolate among these new Rhizobia that was as effective as the highly effective slow-growing reference strain USDA 110.
Abstract: Soybean rhizobia were isolated from two soils with different cropping histories from Hubei province in central China. The first, from Honghu county, has been under soybean cultivation for decades. All of the isolates obtained from nodules on soybeans growing in this soil were fast-growing, acid-producing rhizobia. However, slow-growing, alkali-producing isolates were obtained at higher dilutions of the same soil. The second soil, from Wuchang county, has been under rice cultivation with no record of previous soybean cultivation. All of the soybean rhizobia recovered from this soil, and at higher dilutions of the soil, were typical slow-growing, alkali-producing isolates. The isolates from both soils were grouped by using intrinsic antibiotic resistance, gel immunodiffusion, and fluorescent-antibody procedures. Representative isolates were tested for symbiotic effectiveness with four soybean cultivars (Peking, Davis, Williams, and Ai Jiao Zao) in a pot experiment. There were significant cultivar-rhizobial interactions. Moreover, on each cultivar, there was at least one fast-growing isolate among these new rhizobia that was as effective as the highly effective slow-growing reference strain USDA 110.
TL;DR: The velocity field within two pc of the galactic center has been investigated by observing the forbidden Ne II 12.8 micron fine-structure emission from Sgr West.
Abstract: The velocity field within two pc of the galactic center has been investigated by observing the forbidden Ne II 12.8 micron fine-structure emission from Sgr West. The velocity variation indicates that at least two of the features are large-scale flows of ionized gas. The flow along the southern arm continues all the way north to IRS 8, encircling the center of the galaxy in an arc of about 180 deg. Both the velocity and position along the northern arm are well fitted by a noncircular orbit with mass greater than 3.5 million solar masses within the orbital of about 0.5 pc. These data are taken as evidence for a central black hole of mass three to four million solar masses. A best estimate for the position of the central mass is coincident with IRS 16 NE.
TL;DR: In this paper, the authors organized and summarized the literature on tourism forecasting and concluded that the gravity model is best suited to handle international tourism flows and will be most useful to governments and tourism agencies.
Abstract: Many publications on tourism forecasting have appeared during the past twenty years. The purpose of this article is to organize and summarize that scattered literature. General conclusions are also drawn from the studies to help those wishing to develop tourism forecasts of their own. The forecasting techniques discussed include time series models, econometric causal models, the gravity model and expert-opinion techniques. The major conclusions are that time series models are the simplest and least costly (and therefore most appropriate for practitioners); the gravity model is best suited to handle international tourism flows (and will be most useful to governments and tourism agencies); and expert-opinion methods are useful when data are unavailable. Further research is needed on the use of economic indicators in tourism forecasting, on the development of attractivity and emissiveness indexes for use in gravity and econometric models and on empirical comparisons among the different methods.
TL;DR: A fiber-optic stylet is provided for use with a surgical or diagnostic type needle as discussed by the authors, which comprises an elongated flexible or rigid casing which is adapted to be inserted into the body of a human or animal, and includes at least one transmitting light fiber having a bevelled end which extends to the first end of the casing and that conforms to that of the needle.
Abstract: A fiber-optic stylet is provided for use with a surgical or diagnostic type needle. The stylet comprises an elongated flexible or rigid casing which is adapted to be inserted into the body of a human or animal. It also includes at least one transmitting light fiber having a bevelled end which extends to a first end of the casing and that conforms to that of the needle. A second, receiving light fiber has a bevelled end and is also positioned within the casing, also having its bevelled end located at the first end of the needle. The second fiber-optic element is generally cylindrical and has a reflective surface thereon which is located adjacent to the bevelled end of the light fiber. The apparatus is used to precisely determine the area in which a needle is positioned within a body during a diagnostic or surgical procedure.
Book•
01 Jan 1985TL;DR: In this article, the authors present a preliminary sketch with the hope that they can revise it in the future after they have obtained the criticisms of their learned readers, in order to obtain a more complete sketch.
Abstract: ‘Zen and Western Thought’ is one of the intellectual areas which must by all means be studied and elucidated in today’s world. And yet it is an extremely difficult subject. To deal, in all its ramifications, with this theme which is so vast and difficult to grasp in its core, is quite beyond the powers of the present writer. I shall attempt here only a preliminary sketch with the hope that I can revise it in the future after I have obtained the criticisms of my learned readers.
TL;DR: Chinese hamster spermatozoa gain their ability to move when they descend from the testis to the distal part of the caput epididymis, but it is not until they enter the corpus epididylis that they become capable of fertilizing eggs.
Abstract: Chinese hamster spermatozoa gain their ability to move when they descend from the testis to the distal part of the caput epididymis, but it is not until they enter the corpus epididymis that they become capable of fertilizing eggs. The maturation of the spermatozoa proceeds as they further descend the tract and perhaps continues even in the vas deferens. During transit between the distal caput and proximal cauda epididymides, small membrane-limited vesicles (and tubules) appear on the plasma membrane over the acro somes of the spermatozoa. The number of vesicles appearing on the sperm brane reaches a maximum when the spermatozoa are in the proximal cauda epididymis. It declines sharply in the distal cauda epididymis. Spermatozoa in the vas deferens are free of the vesicles. The origin, chemical nature, and functional role of the vesicles that appear on the sperm surface during epididymal transit must be the subject of further investigation.
TL;DR: In this paper, a modele a trois couches: atmosphere-film stagnant d'eau-eau de mer, atmospherefilm stagnant, and atmosphere film stagnant, is presented.
Abstract: Le transfert de CO 2 a travers l'interface air eau est traite par les phenomenes physico-chimiques, en fonction de la vitesse des vents et de la temperature de l'eau, des reactions de metabolisme organique de CaCO 3 . On etudie un modele a trois couches: atmosphere-film stagnant d'eau-eau de mer
Abstract: The present paper provides the results from a series of laboratory experiments which were conducted to investigate the variable spectral behavior of diagnostic Fe(++) crystal field absorptions in common rock-forming minerals as a function of temperature. The general goal of the study is to refine existing techniques of mineralogic and chemical characterization, based on specific optical behavior which has been measured and correlated in a systematic way. It is pointed out that the presented work, taken together with a number of recent studies, provides new information on the manner in which specific features of mafic minerals combine in rocks and soil spectra, taking into account also variations of identification and subsequent interpretation as a function of planetary surface temperature. The obtained results are directly applicable to interpretation of remotely sensed data for many solar system objects, particularly Mars, asteroids, the moon, earth, and Mercury.
TL;DR: Ethnopharmacological studies in a community of Mayan subsistence farmers in Chiapas, Mexico confirmed that decoctions containing up to 300 mg of dry plant material per kg body weight were widely used and traditionally highly regarded in the treatment of ascariasis, but therapeutic doses of up to 6000 MGKGW of powdered, dried plant had no significant anthelmintic effect on the adults of Necator, Trichuris of Ascaris.
TL;DR: In this article, the authors measured first-order Raman spectra from selected volumes in diamonds under pressure in a high-pressure diamond-anvil cell in both the 180° and 135° scattering geometries and found that the highfrequency component of the diamond line at the diamond-sample interface is found to shift linearly with pressure and exhibits a pressure coefficient of 0.237 cm−1 kbar−1.
Abstract: Micro-Raman spectroscopy has been used to measure first-order Raman spectra from selected volumes in diamonds under pressure in a high-pressure diamond-anvil cell in both the 180° and 135° scattering geometries. The high-frequency component of the diamond line at the diamond-sample interface is found to shift linearly with pressure and exhibits a pressure coefficient of 0.237 cm−1 kbar−1. This shift of the diamond line could be used for pressure determination. The Raman spectra from selected volumes of the diamond anvil at various depths provide useful information about stress distribution in the anvil.
TL;DR: In the Elysium Planitia region of the United Kingdom of Ireland, a large number of meltwater deposits, possible pseudocraters, collapse features within troughs and outflow channels indicate that a layer of subsurface volatiles existed at the time of volcanic activity within this area.
TL;DR: In this article, the authors compared IUE data for 31 solar-type stars with observations of T Tauri stars in order to determine whether the pattern of main sequence chromospheric decay shown by stars older than about 100 million yr extends back to ages of 100 million yrs appropriate for T tauri stars.
Abstract: IUE data for 31 solar-type stars are compared with observations of T Tauri stars in order to determine whether the pattern of main sequence chromospheric decay shown by stars older than about 100 million yr extends back to ages of 100 million yr appropriate for T Tauri stars. An analysis of the time decay of stellar ultraviolet and X-ray emission establishes a relationship between emission level and axial rotation, which is expressed in terms of the Rossby parameter. It is shown that the intensity of ultraviolet chromospheric and transition region lines of solar-type stars declines with age. The activity-age relation for main sequence stars older than about 100 million yr is fitted best by an exponential law whose rate of falloff with age depends on temperature.
TL;DR: Based on FGGE 1,cvel IIIb data, the structural features of 45 day perturbations over a tropical belt (15°N-15°S) during the 1979 summer are detailed as mentioned in this paper.
Abstract: Based on FGGE 1,cvel IIIb data, the structural features of 45 day perturbations over a tropical belt (15°N-15°S) during the 1979 summer are detailed. At the equator, 45 day perturbations which are primarily associated with the zonal wind components of wavenumber 1, propagate eastward (8° of longitude per day) and upward (0.7 km per day), probably indicating downward energy flux. In the Southern Hemisphere tropics (0°–15°S), the 45 day zonal mean wind perturbations propagate downward with an approximate phase speed of 0.8 km per day. In the Northern Hemisphere tropics, they are largely of standing character with the maximum amplitude (3 m s−1) near 200 mb at 15°N. There exists a strong association between monsoon activity over South Asia and changes in the intensity of the equatorial Walker circulation. When active monsoons occur over South Asia, the Walker circulation becomes stronger than usual with prominent 850 mb easterlies (200 mb easterlies) over the eastern Pacific east of the date line an...