Showing papers by "Nova Southeastern University published in 1982"

Quantitative Reef Assessment Studies in Bermuda: A Comparison of Methods and Preliminary Results

Abstract: To compare in quantitative terms both ecological characteristics of the stony coral fauna at various reef sites in Bermuda and available assessment methodologies, we present a study of four separate methods at each of three reef sites. Three plotless (Intersected-length, Quarter point, Point) and one quadrat (Belt-quadrat) methods were employed. Each technique gave similar results but had inherent advantages and disadvantages which involve trade-offs in quantity and type of information generated and time required for use. Pooling of method results revealed that total coral coverage was highest at North Rock (26%), intermediate at Three Hill Shoals (17%), and lowest at South shore (13%). Diversity statistics were highest at Three Hill Shoals, intermediate at North Rock, and lowest at South shore. At all three sites the most dominant species in terms of coverage was Dip/aria sfrigosa; six coral species accounted for 90% of the total coral coverage. This study represents a quantitative comparison of the results and performance of common reef assessment methodologies and the first truly quantitative data on coral coverage, diversity, and distribution for selected reef sites in Bermuda. The importance of detailed knowledge about the ecological characteristics of coral and other benthic communities of coral reefs is now recognized and has been recently stressed by Loya (1978). Quantitative, as opposed to qualitative, methodologies allow more standardized and accurate descriptions of the desired reef community to be made. In this way meaningful intercomparisons of different reef areas as well as of various zones on a single reef or reef complex become feasible. Ecological parameters such as species richness, abundance, diversity, coverage, density, and zonation are common statistics of comparison and become available through quantitative methods. Classical studies on coral reefs prior to the 1970's (see reviews by Stoddart, 1969; 1972) have been primarily qualitative. Although many have utilized quadrats in various ways as data sampling units, it has been difficult to compare between methods and results. Generalizations based on such data are therefore tenuous. More recently, as interest in quantification of aspects of reef ecology has grown, two general classes of methodologies have emerged: (I) plot techniques, utilizing quadrats as sampling units either randomly or arranged belt fashion along a transect line for guidance; and (2) plotless techniques, essentially an outgrowth of the methodology of terrestrial plant ecologists, utilizing a distance (and/or other measurements) from or on a sampling structure, which is usually a transect line of specified length but with no breadth. Loya (1978) provides a comprehensive review of existing plotless methodologies and suggests new procedures for coral reefs which have had success in terrestrial plant ecology. The only previous comparison of reef survey methodologies known to us is by Goodwin et al. (1976) who compared grid, transect and random quadrat methods to total samples in a 400-m2 grid on Grenadine reefs. They concluded that a series of parallel line transects was adequate to delimit dominant species but 4-m2 quadrats were preferable for recognition of less abundant species. We present here results using four different assessment methods to characterize

Response of the pulmonary circulation to acute hypoxia in the growing pig.

Abstract: In a previous article we have analyzed the structure of the growing pig lung and correlated the findings with cardiorespiratory function studies on the same animals (J. Appl. Physiol: Respirat. Environ. Exercise Physiol. 45: 806-817, 1978). The present study analyzes the pulmonary and systemic vascular responses to acute hypoxia in some of those animals at three ages, 2-4, 5-8, and 9-12 wk, the lung of the 12-wk-old pig being structurally similar to that of the adult. In all anesthetized animals, acute hypoxia (5 min 10% fractional inspired oxygen concentration) increased mean pulmonary arterial pressure (Ppa) and total pulmonary resistance (TPR). The increase over base line of Ppa was 41.3% in animals aged 2-4 wk; 83.0% in those aged 5-8 wk, and 136.9% in those aged 9-12 wk; for TPR the increase in the three age groups was 66.4, 92.4, and 138.9%, respectively. This difference in vasoactivity with age is associated with the progressive extension of smooth muscle into the intra-acinar arterial tree, which we have previously shown is an important feature of the structural remodeling that occurs during postnatal lung development in both man and swine.

Effects of Drilling Mud on the Reef-Building Coral Montastrea annularis

Abstract: The skeletal extension and corallite shape of individuals of the Caribbean and Atlantic reef-building coral Montastrea annularis (Ellis and Solander) were measured after more than six weeks' continuous flow-through exposure in laboratory aquaria to treatments of 0, 1, 10 and 100-ppm (μl 1-1) drilling mud. Linear increase of the skeleton (extension rate) and fossa length were significantly depressed in the 100-ppm treatment. Chronic exposure to 100-ppm drilling mud impairs coral skeletal growth rate and possibly interferes with sediment rejection capability by lowering calical relief.

Free networks: minimum norm solution as obtained by the inner adjustment constraint method

Abstract: The main goal of this paper is to show that the solution obtained by adjusting a free network via the inner adjustment constraint method is the minimum norm solution. The latter is a special case of the class of “minimum trace” solutions, where the trace of the variance-covariance matrix for the adjusted parameters is a minimum. The derivations are carried out in terms of pseudo-inverses, the various other forms of generalized inverses having been left out of consideration.

A Numerical Study of the Kuroshio South of Japan

Abstract: A numerical model is used to study the interaction of the Kuroshio with boundary constraints south of Japan. The model consists of two layers with the lower layer inert, and is both nonlinear and quasi-geostrophic. The boundary constraints are highly idealized. The Kyushu Peninsula and its adjacent continental shelf have the form of a V-shaped wedge on an otherwise rectilinear coastline; the Izu Ridge is represented as a square island. Solutions almost always form a meander downstream from Kyushu. The dynamics of meander formation involve the interaction of a Rossby lee wave generated by the Kyushu Peninsula and a westward disturbance forced by the Izu Ridge. Three different quasi-steady paths have been identified. The first path has a meander between Kyushu and the Izu Ridge, passes to the north of the ridge, and is associated with a current of low-volume transport. The second path has a large meander between Kyushu and the Izu Ridge, passes to the south of the Izu Ridge, and always occurs when ...

A note on adjustment of free networks

Abstract: The present paper deals with the least-squares adjustment where the design matrix (A) is rank-deficient. The adjusted parameters\(\hat x\) as well as their variance-covariance matrix (\(\sum _{\hat x} \)) can be obtained as in the “standard” adjustment whereA has the full column rank, supplemented with constraints,\(C\hat x = w\), whereC is the constraint matrix andw is sometimes called the “constant vector”. In this analysis only the inner adjustment constraints are considered, whereC has the full row rank equal to the rank deficiency ofA, andAC T =0. Perhaps the most important outcome points to the three kinds of results 1) A general least-squares solution where both\(\hat x\) and\(\sum _{\hat x} \) are indeterminate corresponds tow=arbitrary random vector. 2) The minimum trace (least-squares) solution where\(\hat x\) is indeterminate but\(\sum _{\hat x} \) is detemined (and trace\(\sum _{\hat x} \) corresponds tow=arbitrary constant vector. 3) The minimum norm (least-squares) solution where both\(\hat x\) and\(\sum _{\hat x} \) are determined (and norm\(\hat x\), trace\(\sum _{\hat x} \) corresponds tow−0

Notes on equivalent forms of the general least-squares solution

Abstract: The general least-squares solution for a rank-deficient system is expressed in several completely equivalent forms. The simplest form is written in terms of A+, the pseudo-inverse of the design matrix A, and of an arbitrary vector whose presence removes the need for more general inverse operators.

Effect of crowding and litter size on retention and reversal learning by rats.

Abstract: A total of 211 male and female rats from litters of 4, 7, or 11 were placed 1, 2, 3, or 4/cage until they were about 84 days old. At this time they were trained to make a position response while, food-deprived and 24 hr. later were tested for retention followed by reversal learning. No significant main effects were found for any stage of training. A positive correlation between trials to criterion and retention suggests that retention may have been facilitated by learning to learn or transfer.

Conclusions and Recommendations on Mobility Disadvantages in Rural Reaches

Abstract: This chapter lists the major conclusions indicated from the findings in the literature search and task analyses undertaken in the previous chapters. It states recommendations that should help public administrators and policy planners to identify the problem areas, formulate alternative solutions, and resolve the issues by (1) promulgating relevant existing programs, (2) innovating practicable new programs, and (3) combining the two into feasible programs that contain an acceptable and reasonable probability of success.

A Multivariate Approach to Restricted Drinking

Abstract: The most significant elements common to persons diagnosed as alcoholic is that they drink too much. Because the range of physiological, psychological, and sociocultural correlates of alcoholism is vast, many authorities in the field reject global etiological theorizing and univariate conceptualizations of alcoholism in favor of a multivariate approach (see, for example, Edwards, 1974; Goldstein & Linden, 1969; Pattison, 1974a, b; Wanberg & Knapp, 1970). The multivariate approach views alcohol dependence not as an entity represented by symptoms but as an array of behaviors and cognitions that collectively produce different types of problems, which are subsequently labeled. To underline this perspective, Horn and Wanberg (1969) have recommended that terms like “alcoholism” and “alcoholic” not be used, for they argue that these terms denote that a specific attribute, “alcoholism,” exists in the unitary fashion implied by the terms.