Showing papers by "University of Central Florida published in 1981"

Measured statistics of laser-light scattering in atmospheric turbulence

Abstract: The statistical properties associated with the intensity fluctuations of a He–Ne laser beam propagating through extended clear-air turbulence over a homogeneous range were measured and compared with existing theoretical models. The statistics were determined by measuring the first five normalized moments of the beam intensity over varying distances from 183 m to 3 km. The beam geometry was approximately that of a spherical wave. Calculated values of the refractive-index-structure parameter Cn2 varied from a low of approximately 10−14 m−2/3 to a high value of the order of 10−10 m−2/3. Thus the data obtained correspond to many conditions of turbulence from weak to strong turbulence in the saturation regime. We found that the data generally support the lognormal model under conditions of weak turbulence and the negative-exponential distribution in the superstrong-turbulence regime. The K distribution fits some of, but not all, the data in the saturation regime. For conditions of strong turbulence before the superstrong regime, none of the above statistical models fits the data well. This is due primarily to the fact that a looping effect appeared in the data whereby the third- and higher-order normalized moments appear to follow a looped curve in the vicinity of their maximum values when they are plotted as functions of the second normalized moment. None of the theoretical curves for the normalized moments of the above-named distributions exhibits this looping effect (since they are essentially one-parameter distributions), and therefore they have limited applicability with respect to our data.

Notes on the occurrence, distribution, and biology of elasmobranch fishes in the Indian River lagoon system, Florida

Abstract: Fifteen species of elasmobranchs, eight sharks and seven rays, have been recorded with reasonable certainty from the Indian River lagoon system on the central east coast of Florida. We collected four shark and six ray species during a three and one-half year study of the northern portion of the lagoon system. Five of these appear to be year-round residents, and the remainder utilize the area only at restricted times of the year or as a nursery ground. The most abundant resident species areDasyatis sayi, D. sabina, andCarcharhinus leucas. Pristis pectinata, once a common resident species, has been extirpated from the lagoons. The distribution of ocean inlets and salinity appear to be major factors affecting diversity and numbers of elasmobranchs in the Indian River system.

Computer readability editing system

Abstract: A computer readability system was developed to serve as an author's aid in improving the ease of comprehending technical manuals and training materials. The system has features to (1) flag uncommon and misspelled words and long sentences, (2) suggest simple replacements for difficult words and phrases, and (3) calculate the readability grade level. Each feature was tested to verify that it provides useful feedback to editors and authors. The program is written in Wang BASIC-2 and can be run on computer equipment costing about $25000.

Analysis of Effects of Distance Running on Self-Concepts of Elementary Students.

Abstract: This study assessed the effects of a systematic running program on self-concepts of fifth and sixth grade pupils in a public elementary school. Thirty subjects were randomly chosen from 110 children, and 15 each assigned to the experimental and control conditions. The Coopersmith Self-esteem Inventory ( 1 ) was administered prior to running for 7 wk. Each subject ran a minimum of one mile at least three times a week. As some lacked the stamina to run continuously for a distance of one mile they were allowed to stop along the course and proceed after a rest. A log was kept for each subject recording when they checked in and out of the course, as well as how far they ran. Many of the subjects chose to run to school and on weekends, but all were required to run the minimum of three miles a week on the designated course. On completion of the program both groups were retested on the inventory. The means and standard deviations on the preand posttests were computed for both groups. Those values with the results of a general multivariate hypothesis test may be found in Table 1. The pretest means of 51.83 and 53.17 exhibited only minimal differences. However, the difference at posttest was substantial ( M = 65.16, M = 50.50). The mean gain was 13.33 points for the experimental subjects; controls lost 2.5 points. The over-all test indicated a significant difference ( F = 9.15, d f = 2/21, P < .0014) as did the univariate rests. The hypothesis of no difference was accepted for the pretest means ( P < .706) and rejected for the posttest means (P < ,002). Although there were no significant differences in the pretest means, those results were used as covariates in the step-down procedure. For the posttest means Table 1 gives P < .00.

Metallic-glass fiber-optic phase modulators.

Abstract: Three different optical-fiber phase modulators utilizing the magnetostrictive properties of a metallic-glass alloy were constructed. By binding the optical fiber to the magnetostrictive metallic glass, the strain induced in the metallic glass that is due to the magnetic field is transferred to the optical fiber. Two ring and one flat linear modulator configurations were investigated. Each modulator's performance was evaluated by measuring the induced phase shift as a function of the excitation frequency of the magnetic field normalized by the fiber length. The highest sensitivity of 75 mrad/cm-Oe was attained for the linear modulator.

Deletion analysis of the tumorous-head (tuh-3) gene in Drosophila melanogaster.

Abstract: In the presence of the naturally occurring maternal-effect alleles tuh-1h or tuh-1g, the tuh-3 mutant gene can cause the tumorous-head trait or the sac-testis trait. The tuh-3 gene functions as a semidominant in the presence of the tuh-1h maternal effect. Eye-antennal structures are replaced by posterior abdominal tergites and genital structures. If tuh-1h is replaced by its naturally occurring allele tuh-1g, tuh-3 functions as a recessive hypomorph and the defect switches from anterior to posterior structures, with a male genital-disc defect appearing with variable penetrance. Function and regulation of tuh-3+ may better be understood in light of the cytological localization of tuh-3 either adjacent to or as part of the bithorax complex. The tuh-3+ gene product appears to be essential for normal development, at least in the posterior end of the embryo.

The Evidential Value of Automobile Paint. Part II: Frequency of Occurrence of Topcoat Colors

Abstract: Frequency of occurrence data are valuable to forensic scientists in their quest to properly assess the evidential value of automotive paint exhibits. A survey of automobile topcoat paint colors is presented with a sample size of 43 000 vehicles covering six eastern states in the United States. In addition, the results of a second survey utilizing more discriminating color groups for 2000 vehicles in central Florida is given. Comments on statistical validity and sample size for frequency distribution studies are provided.

Sport, Heroes and Myth

Abstract: A myth is a symbolic structure which expresses moral and aesthetic values; it is the realm through which ultimate reality is mediated to man. Ernst Cassirer notes that one of the central qualities ...

Analysis of a new homoeotic mutation (iab-2) within the bithorax complex in Drosophila melanogaster

Abstract: A new mutation designated infra-abdominal-2 (iab-2) arose spontaneously with a new bithorax mutant (bx9) in chromosome 3B from a tumorous-head (tuh-1; tuh-3) strain. This study provides a description of iab-2 and localizes the gene within the bithorax complex. In iab-2 flies the 2nd abdominal segment resembles the 1st abdominal segment. The 2nd sternite shows a reduction in number of bristles, completely lacking the longest class, and when present, the Wheeler's organ is modified. The longest 2nd tergite bristles always show reductions in length. Deletion studies indicate that iab-2 lies to the right of bithoraxoid and the left of infra-abdominal-8 at 89E3-5 on the salivary gland chromosome map. Addition of iab-2 to the existing repository of homoeotic mutations within the bithorax complex provides further evidence of a proximal-distal orientation in the chromosome for these genes and should provide an important new tool for ordering the genes in the right side of the bithorax complex.

Benthic Macroinvertebrates of a Hydrilla Infested Central Florida Lake

Abstract: Benthic macroinvertebrates and physicochemical parameters were monitored simnl taenously with hydrilla (Hydrilla verticillata Royle) biomass in a Central Florida lake. Twenty-seven of the 54 taxa of benthic macroinvertebrates collected were members of the family Quronomidae. Chironomids and oligochaetes numerically dominated the benthos, comprising 82% of the individuals collected. The greatest numbers of taxa and individuals were found during the winter when hydrilla biomass was low. Hydrilla biomass ranged from 0.382 kg/m2-FW in April, 1977 to 2.275 kg/m2-FW in October, 1977. Low numbers of macroinvertebrate taxa and individuals were collected from bottom sediments during sunnier and fall. Dissolved oxygen concentrations at the bottom were approximately 2.0 ppm during summer and fall and possibly limited benthic organisms. The annual means for the Shannon and Simpson indices for the benthos were 1.92 and 0.35, respectively.

Learning Disabilities Identification: Do Researchers Have the Answer?

Abstract: One hundred and thirteen studies were reviewed to determine how researchers identify their LD samples. Populations were compared on academic, process, intelligence, exclusion, and discrepancy components as well as the demographic characteristics of age, sex, and grade. Researchers were found most often to select the academic and intelligence components and the demographic characteristics of age and sex to identify their populations. However, these components were described in a variety of ways. Less than half of the researchers used the process or exclusion components or included a description of grade placement. The article includes suggestions for obtaining more generalizability of research findings based on results of the review of existing research studies.

Some New Worldwide Cloud-Cover Models

Abstract: Using daily measurements of day and night infrared, and incoming and absorbed solar radiation obtained from a Tiros satellite over a period of approximately 45 months, and integrated over 2.5 deg latitude-longitude grids, the proportion of cloud cover over each grid each day was derived for the entire period. For each of four 3-month periods, for each grid location, estimates a and b of the two parameters of the best-fit beta distribution were obtained. The (a, b) plane was divided into a number of regions. All the geographical locations whose (a, b) estimates were in the same region in the (a, b) plane were said to have the same cloud cover type for that season. For each season, the world is thus divided into separate cloud-cover types.

Influence of homoeotic genes on the aldehyde oxidase pattern in imaginal discs of Drosophila melanogaster

Abstract: In a study of the regulation of enzyme patterns in imaginal discs the aldehyde oxidase pattern was determined for some homoeotic mutations of D. melanogaster. Earlier indications that suggested that this pattern follows the determinitive state of compartments within imaginal discs were confirmed by the aldehyde oxidase (AO) pattern of both the wing and haltere discs from en1; bx3, en1; pbx, and en1; bx3 pbx larvae and the antennal discs from Antp73b and ssa larvae. We additionally analyzed whether AO activity depended on the determinative state of an entire compartment or was expressed autonomously in clones. Homozygous engrailed clones were induced by mitotic recombination. From the AO clones found in normally negative areas of the posterior compartment it was concluded that enzyme activity depended upon the determinative state of the cells and was not a function of the compartment as a whole. The results are described with reference to a scheme in which compartmental and subcompartmental selector genes are thought to determine a binary code on which AO patterns depend.

Aldehyde oxidase distribution in picture-winged hawaiian drosophila: evolutionary trends.

Abstract: Dipteran imaginal discs, especially those of Drosophila, are a unique system for the study of genetic control in determination and differentiation (Gehring, 1978). Although differentiation of adult structure is limited to metamorphosis, experiments utilizing clonal analysis have shown that groups of cells within imaginal discs become more and more restricted in their determination through the larval period. Morphologically, cells of the discs appear to be similar but Crick and Lawrence (1975) have hypothesized that they may differ from one another by enzyme profile which could be visualized histochemically. Major steps toward this visualization have been taken for the enzyme aldehyde oxidase (AO). A great deal is known of the biochemistry and genetic control of this enzyme in Drosophila. Much of this work is reviewed by Dickinson and Sullivan (1975). Dickinson (1971) was the first to histochemically localize AO in Drosophila melanogaster larvae and adults and find tissue-specific patterns of expression. Patterns of AO acitivity in Drosophila imaginal discs were first observed by Janning (1972, 1973) who also showed, using cell markers in gynandromorphs, that aldehyde oxidase is cell autonomous. Distribution of aldehyde oxidase in larval tissues and imaginal discs was surveyed by Kuhn and Cunningham (1978). These investigators were also able to show that in homoeotic mutants disc specific staining patterns are altered reflecting the change in determination (Kuhn and Cunningham, 1977a, 1977b). It is quite clear from these and other studies that tissue specificity of enzyme activity is a result of genetic regulation. The importance of considering regulatory as well as structural gene changes in evolution was emphasized by King and Wilson (1975). Sprey (1977) surveyed aldehyde oxidase distribution in imaginal discs of several dipterans including D. melanogaster, its sibling, D. simulans, and D. hydei. There is probably no better group of Drosophila in which to examine evolutionary trends in developmental regulation than the Hawaiian species. Precise relationships for 101 species of the picturewinged group have been determined based on banding sequences in the salivary gland polytene chromosomes (Carson et al., 1970; Carson and Kaneshiro, 1976). For these species a great deal is also known about their ecology, behavior, morphology and genetic variability. Dickinson (1979, 1980) has begun to examine these species for tissue-specific gene expression and has demonstrated cis-acting regulatory elements controlling expression of ADH and AO. We have chosen to survey ten species of picture-winged Hawaiian Drosophila, representing several branches of the phylogeny, examining them for larval tissuespecific expression of aldehyde oxidase and patterns of expression within the imaginal discs. This paper describes the AO activity patterns observed in relation to the questions: are patterns of expression species specific and do closely related species manifest similar distribution patterns?

Carboxymethyl cellulase activity in the myxomycete Physarum polycephalum

Abstract: Carboxymethyl cellulase (CMCase) activity at different life cycle stages in Physarum polycephalum was measured viscometrically in homogenized axenic cultures incubated with CMC. Protein concentrations were determined using the Bio-Rad (Coomassie Blue) assay. Mean activity for several dilutions of the homogenized samples ranged from 318 CMCase activity units/hr/mg protein in old plasmodia to 2423 CMCase unit/hr/mg protein in dry spores. Activity in spores and sclerotia was higher than in a vegetative plasmodium. This CMCase activity level is comparable to that found in some true fungi and suggests that myxomycetes may utilize cellulose and play a role in the breakdown of plant products. (Refs. 18).

Functional Planning Tool: Tourism Impact Model

Abstract: The Tourism Impact Model (TIM) is an economic modeling technique that structures the existing relationship between tourism expenditures and various economic impacts. It provides a system of average impact multiplier linkages relating the tourism expenditures to some economic consequences. The model also considers the intermediate impact of capital investment induced by tourism activity. There are two basic types of equations comprising the TIM. One set is the various sectoral investment functions, which are estimated econometrically. The investment equations estimate the expected capital feedback resulting from current economic activity. The second set is current economic impact equations. The parameters of these latter equations are derived from the regional input-output model which determine the levels and the distributions of the various total economic resources required to satisfy a given final demand (expenditures) in the tourism sectors.

Some markovian measures in an organizational manpower planning model

Abstract: A fractional flow, manpower planning model has been proposed in which the transition fractions can be calculated from economic parameters characteristic of the organization, its competitors, and its employees. This implies that the organization can, to some degree, regulate the movement of its employees through its ranks. This present study suggests four quantities to look at in planning company policy. All four quantities can be computed from the transition Markov processes. These four quantities are: the expected value and the variance of the number of time periods that an individual spends in rank j, given that he started in rank i, and the expected value and the variance of the number of time periods before an individual leaves the organization, given that he started in rank i. By taking advantage of the nature of the proposed model, the matrix equations for the four quantities are expressed as relatively simple algebraic expressions. Finally, the procedure is illustrated with two examples.