Showing papers by "Nova Southeastern University published in 1983"

Pleistocene sea levels from raised coral reefs of haiti.

Abstract: The elevations and ages of a sequence of three uplifted Pleistocene coral reefs on the Northwest Peninsula of Haiti have been determined. With the assignment of a sea level of +6 meters (relative to the present day) at 130,000 years before present and constant uplift of the reefs, the data indicate that sea level stood –10 and –13 meters at 108,000 and 81,000 years before present, respectively. These results are in substantial agreement with those reported for Barbados and New Guinea and support the hypothesis of constant uplift for each area. Sea level data from raised reefs indicate that the interglacial marine oxygen isotope oscillations during oxygen isotope stage 5 are a result of 30 percent ice volume effects and 70 percent temperature effects.

A Model of Tropical Ocean-Atmosphere Interaction

Abstract: A model is used to study ocean-atmosphere interaction in the tropics. The model ocean consists of the single baroclinic mode of a two-layer ocean. Thermodynamics in the upper layer is highly parameterized. If the interface is sufficiently shallow (deep), sea surface temperature is cool (warm). The model atmosphere consists of two wind states that interact with the ocean according to the ideas of Bjerknes. When the eastern ocean is cool, the trade winds expand equatorward in the central Pacific, simulating an enhanced Walker circulation (WC). When the eastern ocean is warm, the trade winds expand eastward, simulating an enhanced Walker circulation (WC) there. For reasonable choices of parameters, the model oscillates at all time scales associated with the Southern Oscillation. The WC has positive feedback with the ocean. This interaction generates persistence, and thereby makes it possible for solutions to oscillate at long time scales. Interaction of the HC with the ocean prevents the model from ...

Environmental Correlates of Hermatypic Coral (Montastrea annularis) Growth on the East Flower Gardens Bank, Northwest Gulf of Mexico

Abstract: Time series of annual linear growth increments from 12 Montastrea annularis (E. and S.) collected at the East Flower Gardens Bank reef in the northwestern Gulf of Mexico have a common pattern. This is best expressed in an index master chronology (average by year of the annual percentage deviations from the mean of each coral). Comparisons with time series of environmental data indicate that coral extension rates vary positively with seasonal (February through May4 months) surface water temperature and negatively with annual discharge of the Atchafalaya River. We propose that secular variations of water temperature and other parameters are the major long term controls of coral growth in the area. Our data do not support the view that sinking of the Flower Gardens reef, caused by catastrophic collapse of the underlying substrate, has been a prime influence on the corals.

On the Formation of Whitecaps by a Threshold Mechanism. Part I:. Basic Formalism

Abstract: In this paper and the two which follow we seek to evaluate the hypothesis that deep water whitecapping is predictable in terms of a threshold mechanism involving the vertical acceleration; i.e., that whitecapping occurs in regions of fluid where the surface wave motions require the downward acceleration to exceed some dynamical threshold. Our point of view is macroscopic and wave-oriented. We do not seek to analyze or describe in any detail motions within a whitecap itself; rather we concentrate on assessing the geometrical and geometro-statistical consequences of the threshold assumption and on comparing these consequences with observation. This first paper develops the descriptive framework for he investigation and examines several statistical predictions of a threshold model. The concept of a breaking variable is introduced and its statistics are related to the directional wave spectrum. The surface geometry of whitecap events is discussed and three classes of geometrical moments are defined. ...

On the Formation of Whitecaps by a Threshold Mechanism. Part III: Field Experiment and Comparison with Theory

Abstract: This paper is the third in a series of papers which seek to evaluate the hypothesis that deep water whitecapping is predictable in terms of a threshold mechanism involving the vertical acceleration. Parts I and II of the series have developed the descriptive framework for the investigation and examined several geometro-statistical predictions of the threshold model, the first by direct integration of the joint probability densities for the vertical acceleration, the second by Monte Carlo simulation of the vertical acceleration field. In Part III we describe a field experiment designed to study the statistical geometry of the whitecap field and to test the theoretical predictions of Parts I and II. This experiment, conducted at an experimental site in the Bight of Abaco, Bahamas, combines a series of photographs of whitecap events with simultaneous array measurements of waves. The photographs were taken from above the water surface and cover an area nominally 10 m on a side. A total of 2292 whitec...

Transient coastal currents and inertio-gravity waves

Abstract: Solutions are found for the flow field generated near a coast by the sudden application of an alongshore wind stress. Alongshore geostrophy is not assumed, and so the near-inertial oscillations are retained. The model is alongshore independent, hydrostatic, continuously stratified, has a well-mixed surface layer, and admits vertical diffusion in the anterior. The asymptotic form of the solution for large time and fixed position shows that the inertial oscillations decay like t −1/2 , leaving behind an accelerating coastally trapped baroclinic jet and a steady upwelling circulation. Calculations for up to 5 days show coastal inhibition of the inertial oscillations within the Rossby radius, outside which they increase in large parts of the ocean interior. The increase is due in part to the downward leakage of coastal inertial energy from the mixed layer and in part to the offshore leakage near the bottom. Several weeks may be needed to obtain significant decay everywhere in the flow field. Estimates of certain properties of the inertial oscillations in the model are in fair agreement with observations.

On the Formation of Whitecaps by a Threshold Mechanism. Part II: Monte Carlo Experiments

Abstract: This paper is the second of three which seek to evaluate the hypothesis that deep water whitecapping is predictable in terms of a threshold mechanism involving the vertical acceleration. The geometro-statistical computations of Part I of the series proceeded via direct integration of the joint probability densities for the vertical acceleration. In Part II we explore a second technique for computing whitecap statistics. This technique involves the Monte Carlo simulation of the vertical acceleration field and of the corresponding “breaking” variable field. Subsequent collation of various whitecap statistics parallels the analysis of whitecap photographs to be described in Part III. Linear simulations for two types of JONSWAP spectra (Trials 1 and 2) and for a Pierson-Moskowitz spectrum (Trial 3) are presented. The resulting statistics, generated with limited resources, are sparse but pertinent. Significant improvement in the reliability of these statistics could be effected by using a vector proce...

Contributions to Behavioral Treatment from Studies on Programmed Access to Alcohol

Abstract: Major developments in research involving the alcohol-alcoholic interaction are presented against a backdrop of the traditional perspective of alcoholism. Studies explaining the effects of alcohol, factors influencing drinking patterns, the significance of alcohol for the alcoholic, expectations regarding alcohol use and its affective and social consequences, the parameters of alcohol use, the question of control of alcoholism, and a number of treatment related issues are reviewed. It is concluded that much of this research is provocative and may recommend a reassessment of current thinking about the Nature of alcohol abuse and dependence. Such a reassessment, however, is seen to be difficult to make, for the task likely will require a paradigmatic shift.

The Practitioner's Dilemma:: Depression or Early Dementia?

Abstract: The clinical differentiation between depression and early dementia (non-specific type) is developed for the private practitioner. Eighteen respective items relating to the differential diagnosis between these two disorders are offered to assist the clinician in making a more accurate and reliable diagnosis based on current research findings.

Behavioral Treatment Methods for Alcoholism

Abstract: This chapter offers a review of the behavioral methodology directed to the treatment of alcoholism. Beginning with an outline of the theoretical bases of behavior therapy and assessment, a review with some historical perspective is undertaken of the chemical, electrical, and covert aversion treatments of alcoholism. Thereafter, the procedures of the social skills-training strategies (including marital skills and assertiveness training) are presented, followed by a discussion of the relaxation and desensitization techniques. The operant methodologies are illustrated by contingency contracting and the community-reinforcement approaches. Within the broad-spectrum procedures, a description of self-control training and an example of a broad-spectrum treatment study are offered. It is noted that although the merits of these various techniques are becoming widely recognized in the alcoholism treatment literature, the behavior therapeutic approaches to alcoholism have yet to receive widespread public acceptance. It is anticipated that future studies of treatment effectiveness will contribute to an increasing appreciation of the advantages of behavioral therapies to the management of alcohol abuse and dependence.

Assessment of role-play generalization across qualitatively different situations

Abstract: Role-play generalization of newly acquired assertive behavior was assessed across different response situations in a clinical outpatient sample. Prior to assertive training, subjects completed two paper-and-pencil inventories and a series of role-play situations. Behavioral role-play scenes included four response forms: making requests, expressing affection, standing up for rights, and expressing displeasure. Subjects were randomly assigned to treatment or test-retest conditions and the treatment subjects received six 2-hr sessions of assertion training using modeling, behavior rehearsal, instruction, positive reinforcement, assignedin vivo homework, bibliotherapy, and daily recordings of assertive behavior. Posttreatment, subjects completed the paper-and-pencil measures, trained role-play scenes, and a set of dissimilar untrained scenes requiring different response forms (giving compliments, receiving compliments; refusing unreasonable requests and expressing justified anger). Videotapes were rated blindly and in random order at the conclusion of the study by trained judges. Treatment and test-retest subjects were equivalent prior to training. Posttreatment for the two groups differed in self-report, role-play behavior in trained situations, and role-play behavior in untrained dissimilar situations (allp<.001). MANOVA with repeated measures confirmed that trained and generalization role-play scenes were quantitatively, as well as qualitatively, different, confirmed that treatment and test-retest subjects exhibited different performance levels posttreatment on both trained and generalization scenes, and revealed four significant interactions (allp<.001). Implications of the interactions are discussed. Canonical correlation revealed that subjects displayed significant commonality in their behavioral profiles across different response forms. The findings indicate that complex training resulted in generalization from trained situations to untrained and dissimilar generalization scenes for the clinical outpatient sample.

Current perspectives in neo-pavlovian temperament theory and research: A review

Abstract: Developments in neo-Pavlovian temperament theory and research during the past two decades are reviewed. Two major research orientations can be distinguished in this field. The first, and historically the older, has centred round a search for operational definitions and measures of parameters of reflexive behaviours, both conditional and unconditional, which collectively describe dimensions of variation in higher nervous activity in human beings. Ten primary, and five secondary properties are described, together with associated measurement techniques, and correlated individual differences in performance in a variety of situations and tasks. Evidence for the heritability of these properties is also surveyed. The second, and more recent trend, has drawn on evoked electroencephalographic data to support a model describing general temperament features of activity and emotionality, mediated, respectively, by activation of fronto-reticular and fronto-limbic cortical connections. By contrast with the hig...

Crowding and litter effects on retention and reversal learning by young rats.

Abstract: 72 rats both male and female from litters of 4 or 11, placed 1, 2, or 4/cage until age 65 days, acquired a position response under food deprivation. After 24 hr. each rat relearned to the same criterion, which was followed immediately by reversal training. Males acquired the response sooner, but females and litters of four retained more than their counterparts. Males housed 1/cage were slower to reverse than males housed 4/cage. When each group was subdivided into rats that consumed the reward upon the first correct response occurrence (immediate eaters) and those which did not consume the reward immediately (delay eaters), delay eaters required more trials to acquisition criterion, were slower to respond, had higher savings scores, and took longer to reverse. These findings, coupled with significant correlations of lower savings scores with greater increases in latency from acquisition to re-learning, suggested that emotionality interfered with retention by males and litters of 11. Similarly, emotionalit...

Alcohol Use and Abuse

Abstract: Those engaged in scientific pursuits only occasionally cast themselves in the role of social activists; yet, as Koestler (1968) so clearly articulated, the contributions made by scientists and thinkers on the leading edge of a conceptual development typically have profound social and political implications. The social context, however, must be ready to accept the emerging perspectives or social acceptance will not occur (see also Kuhn, 1970).