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An Assessment Of Africanized Honey Bees (Apis Mellifera L.) As Crop Pollinators., Robert George Danka Jan 1987

An Assessment Of Africanized Honey Bees (Apis Mellifera L.) As Crop Pollinators., Robert George Danka

LSU Historical Dissertations and Theses

Neotropical Africanized honey bees are predicted to replace European bees and become the primary agricultural pollinators in the southern and coastal regions of the United States. This research used direct comparative studies to assess foraging activities and beekeeping-management responses which are expected to govern the performance of Africanized bees as crop pollinators. European colonies fielded on average $3\times$ as many foragers as did Africanized colonies and had percentages of colony members foraging that were nearly $3\times$ as high. European colonies also had much greater variability in foraging activity (ranges: 42-1679 foragers for European bees; 119-352 foragers for Africanized bees); European …

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Rice Stink Bug, Oebalus Pugnax (F.), On Rice: Evaluation For Plant Resistance, Interaction Of Field Fungi With Feeding Damage, And Evaluation Of Insecticides For Control., Marieanne Eva Hollay Jan 1987

Rice Stink Bug, Oebalus Pugnax (F.), On Rice: Evaluation For Plant Resistance, Interaction Of Field Fungi With Feeding Damage, And Evaluation Of Insecticides For Control., Marieanne Eva Hollay

LSU Historical Dissertations and Theses

Feeding punctures of the rice stink bug (RSB), Oebalus pugnax (F.), provide fungi entry sites into rice, Oryza sativa (L.), grains and kernels (hulled grains). Feeding sheaths also serve as a source of nutrients for fungi. Grain spotting fungi did not affect the percentage of spotted kernels (pecky rice) and significantly reduced full grain weight only at low infestation rates of one and two RSB per panicle. Panicles had been treated with a single application of propriconazol (1000 ppm) soon after flowering and later infested in the early milk stage with RSB adult pairs for 9 days. Propriconazol was not …

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Bionomics Of The Sugarcane Borer, Diatraea Saccharalis (F.), In Sweet Sorghum, Sorghum Bicolor (L.) Moench., Billy Wayne Fuller Jan 1987

Bionomics Of The Sugarcane Borer, Diatraea Saccharalis (F.), In Sweet Sorghum, Sorghum Bicolor (L.) Moench., Billy Wayne Fuller

LSU Historical Dissertations and Theses

Economic impact studies revealed that the sugarcane borer, Diatraea saccharalis (F.), reduced sweet sorghum yield of total sugars up to 46% in artificially infested field trials. A significant relationship was found between D. saccharalis damage and yield loss that indicated an economic injury level of 10% bored internodes. Stalk weight, percent sucrose, and total sugars were negatively correlated to D. saccharalis damage; and increased fiber content was positively correlated to percent bored internodes. Information from damage levels, along with survival records, indicated that the economic threshold was reached when approximately 5% of the sweet sorghum plants contained small D. saccharalis …

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Estimation Of Heritabilities, Genetic Correlations, And Response To Selection For Growth, Body Size, And Processing Traits In Red Swamp Crawfish, Procambarus Clarkii (Girard)., Charles Gregory Lutz Jan 1987

Estimation Of Heritabilities, Genetic Correlations, And Response To Selection For Growth, Body Size, And Processing Traits In Red Swamp Crawfish, Procambarus Clarkii (Girard)., Charles Gregory Lutz

LSU Historical Dissertations and Theses

Potential for genetic improvement of red swamp crawfish, Procambarus clarkii, and the possibility of negative selection for growth in cultured stocks as a result of harvesting practices have recently been the subject of speculation. This study provided indications of the potential for improvement of growth and processing traits in P. clarkii through selection. After 150 days growout in fiberglass pools planted with rice (Oryza sativa), P. clarkii from each of 39 full-sib families nested within 15 half-sib families were weighed and measured for total length, carapace length, carapace width, abdomen width, abdomen depth, chela length, chela width, abdomen meat weight, …

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Consumption, Utilization, Biology, And Economic Injury Levels Of Fall Armyworm, Spodoptera Frugiperda (J. E. Smith), On Selected Bermudagrasses., Tasanee Jamjanya Jan 1987

Consumption, Utilization, Biology, And Economic Injury Levels Of Fall Armyworm, Spodoptera Frugiperda (J. E. Smith), On Selected Bermudagrasses., Tasanee Jamjanya

LSU Historical Dissertations and Theses

The effects of nine bermudagrass, Cynodon dactylon (L.) Pers., varieties and strains on the development, survivorship, consumption and utilization, preference, and host suitability of the fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith) were determined. The bermudagrasses tested were 'Coastal', 'Tifton 44', 'Tifton 78', 'Tifton 292', 'Grazer', #1 R12P5, 'OSU 71 X 6-7','OSU 74 X 11-2', and 'OSU 74 X 12-1'. 'Tifton 292' was the most preferred grass by neonate larvae, while 'OSU 74 X 11-2' was the least preferred grass. 'Tifton 78' was the most susceptible host, while 'OSU 71 X 6-7' was the least suitable host to FAW …

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A Seasonal And Ontogenetic Examination Of The Reproductive Biology Of Pseudoplusia Includens (Walker)., Linda Jean Mason Jan 1987

A Seasonal And Ontogenetic Examination Of The Reproductive Biology Of Pseudoplusia Includens (Walker)., Linda Jean Mason

LSU Historical Dissertations and Theses

Laboratory observations on the mating behavior of soybean loopers, Pseudoplusia includens (Walker), indicated a calling pattern that was highly variable both within individual females over time and among individuals. However, some trends were apparent. The onset of calling showed temporal advancement over the first three nights of calling after adult emergence; the duration of calling showed a temporal advancement during the first six nights, while the termination of calling receded over the same period then reversed its trend. The majority of females initiated calling three nights following emergence while maximum percent calling was observed around five hours after the onset …

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Bovine Enteropathogenic Coronavirus: The Effect Of The Host Cell And Trypsin Modification On The Virus Structure, Cytopathic Expression, And Infectivity., Karen P. St. Cyr-Coats Jan 1987

Bovine Enteropathogenic Coronavirus: The Effect Of The Host Cell And Trypsin Modification On The Virus Structure, Cytopathic Expression, And Infectivity., Karen P. St. Cyr-Coats

LSU Historical Dissertations and Theses

Human rectal tumor-18 (HRT-18) cell clones 3F3, 3E3, D2, and 4B3 exhibited differences in cellular morphology in Giemsa-stained cultures and developing monolayers. Differences were evident in growth kinetics and plating efficiency of each clone. The clones produced colonies in soft agar, demonstrating anchorage independence. Cytopathic expression (CPE) including cytoplasmic vacuolization and cell fusion occurred in BCV-L9-infected clones 3F3, D2, and 3E3. Cell fusion was inapparent in clone 4B3. Bovine coronavirus strain L9 (BCV-L9) and 5 wild-type isolates replicated in HRT-18 cells, inducing cell fusion. Strain L9, exclusively, replicated in D2BFS cells, requiring trypsin to induce cell fusion. Strain L9 produced …

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Woody Vegetation Of A Disjunct Oak Woodland In East-Central Nebraska., Debra Ann Beightol Jul 1986

Woody Vegetation Of A Disjunct Oak Woodland In East-Central Nebraska., Debra Ann Beightol

Student Work

The woody vegetative composition of the Oak Glen Wildlife Management Area, a disjunct oak woodland in Seward County, Nebraska, was assessed using the Point-Quarter method. Based on data from three size categories, the presettlement composition of the woodland appears to have been a bur oak (Quercus macrocarpa) dominated community which, based on spacing and growth form, may have been savanna-like. Under present management, this community is succeeding to one consisting primarily of elm (Ulmus spp.), and hackberry (Celtis occidentalis)

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Gene Expression During The Latent And Replicative States Of The Epstein-Barr Virus, Ronald John Weigel May 1986

Gene Expression During The Latent And Replicative States Of The Epstein-Barr Virus, Ronald John Weigel

Yale Medicine Thesis Digital Library

Gene expression of the Epstein-Barr virus (EBV) was examined during the latent and lytic viral cycles. During latency the virus expresses two small RNAs (EBERs) and the EB nuclear antigen (EBNA). A gene encoding one peptide of the EBNA complex was mapped using S1 nuclease analysis. EBNA peptide is encoded by a 2028 base exon contained within the EBV Bam HI K fragment; the 3' end of this exon occurs 30 bp after the polyadenylation signal AATAAA and the 5' end occurs within a splice acceptor site. The latent state was disrupted experimentally by treatment with phorbol ester or superinfection …

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An Investigation Of The Chlorophylls Of Selected Prasinophyte Algae., Leslie Carlat Kwasnieski May 1986

An Investigation Of The Chlorophylls Of Selected Prasinophyte Algae., Leslie Carlat Kwasnieski

Student Work

Introduction: Chlorophyll a is the prevalent light-collecting pigment in eukaryotic, photosynthetic organisms. Several different chlorophylls exist in nature, but all autotrophic plants contain chlorophyll a (Bogorad, 1976). The majority of these chlorophyll a molecules function to absorb light and channel the excitation energy to photochemical sites in reaction centers. Chlorophylls b, c, d, and e, carotenoid pigments and phycobiliproteins are organized into antenna systems which absorb light maximally at different wavelengths. This design permits the visible light spectrum to be exploited (Foyer, 1984) for energy by different photosynthetic organisms. Chlorophyll b is present in higher plants, Chlorophyta, Prasinophyceae, and Euglenophyta; …

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Recent Ponderosa Pine (Pinus Ponderosa) Occurrence In Nebraska Sandhills Prairie., Ernest M. Steinauer Apr 1986

Recent Ponderosa Pine (Pinus Ponderosa) Occurrence In Nebraska Sandhills Prairie., Ernest M. Steinauer

Student Work

Four stands of ponderosa pine (Pinus ponderosa), situated within sandhills prairie sites in north central Nebraska, were evaluated for age distribution, reproductive status and spatial distribution. Trees were generally young; of the 563 individuals sampled, 11 had establishment dates prior to 1900 with the oldest dated 1868. All trees greater than 55 years old bore cones. Initial tree establishment appears to have occurred on north facing slopes where both the oldest trees and 92% of all trees observed were located. Age structure data show pine populations are increasing in all four prairie sites. This study shows that, under present management, …

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Report Of The Director, University Of South Florida Botanical Garden, March 28, 1986, Frederick B. Essig Mar 1986

Report Of The Director, University Of South Florida Botanical Garden, March 28, 1986, Frederick B. Essig

USF University Archives and Documents

Report of Frederick B. Essig, Director of University of South Florida Botanical Gardens dated March 1986. Topics include specimen acquisitions, plant loss due to weather, plant sale, funding, garden use, educational outreach, campus partnerships, botany database, and future goals.

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Quantifying Spatial Patterns Of Overgrowth In Epibenthic Communities, David S. Wethey, Linda J. Walters Mar 1986

Quantifying Spatial Patterns Of Overgrowth In Epibenthic Communities, David S. Wethey, Linda J. Walters

Faculty Publications

A method is presented that allows rapid and accurate measurement of changes in the spatial pattern of space occupation in encrusting organisms. The boundaries of organisms are represented as polygons, and geometric difference calculations are used to establish the perimeters of the areas gained or vacated between sampling dates. The influence of interspecific interactions on occupation of space is also quantified: geometric intersection calculations are used to define the perimeters of the areas gained or lost in overgrowth interactions. A method is presented for estimating the sampling frequency necessary for detection of significant changes in occupation of space. The method …

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Control Of Human Limb Movement Trajectories, Warren Garfield Darling Jan 1986

Control Of Human Limb Movement Trajectories, Warren Garfield Darling

Digitized Theses

It is common experience that movements we make do not end at the same position during repeated attempts. Variability must, however, develop during movements and not just at their endpoint. Recent studies of the effects of perturbations on limb movements have suggested that the entire trajectory of movements, rather than their endpoint, may be controlled. Experiments were carried out to further examine this hypothesis by studying the variability in human arm movement trajectories and related muscle electromyographic (EMG) activities as a function of movement speed and practice.;Variability in both movements and the EMGs of involved muscles depended on both movement …

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The Role Of Mouse Mammary Tumor Virus In The Induction And Progression Of Mouse Mammary Tumors, Douglas Andrew Gray Jan 1986

The Role Of Mouse Mammary Tumor Virus In The Induction And Progression Of Mouse Mammary Tumors, Douglas Andrew Gray

Digitized Theses

Mouse mammary tumor virus (MMTV) is a retrovirus which causes mammary tumors in many strains of mice. An essential part of the viral life cycle involves the integration of a double-stranded DNA provirus into the host cell genome. Tumorigenesis is thought to be mediated by such integrated proviruses.;Restriction endonuclease analysis of the DNA from a series of cell sublines from a single MMTV-induced mammary adenocarcinoma revealed that the original tumor was composed of tumorigenic and nontumorigenic cells whose proviral content could not be correlated with tumorigenicity. The tumorigenic sublines however contained a single provirus which was correlated with tumorigenicity. The …

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Molecular Analysis Of Spontaneous Deletions In Minute Virus Of Mice Dna, Frances Aileen Hogan Jan 1986

Molecular Analysis Of Spontaneous Deletions In Minute Virus Of Mice Dna, Frances Aileen Hogan

Digitized Theses

Minute virus of mice (MVM) is a helper-independent parvovirus that contains a linear, single-stranded DNA genome with short self-complementary regions at the termini. During an infection of mouse cells with MVM, a high rate of spontaneous deletion is observed. By hybridization with specific probes, it was determined that a proportion of the deleted DNA genomes had retained both termini but contained an internal deletion. Nucleotide sequence analysis of eight cloned isolates showed that internal deletions had occurred at short direct repeats. Slipped mispairing at a replication fork is a possible mechanism for the generation of these mutants. Deletion formation is …

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The Effects Of Estrogen, Progesterone And Ionized Calcium On Seizures During The Menstrual Cycle Of Mature Female Epileptics, John Jacono Jan 1986

The Effects Of Estrogen, Progesterone And Ionized Calcium On Seizures During The Menstrual Cycle Of Mature Female Epileptics, John Jacono

Digitized Theses

More males than females are affected by epilepsy. This is so for all ages, with the exception of puberty. During the pubertal years, incidence rates of epilepsy are higher in females than in males.;Factors suspected of causing epilepsy are numerous, however the role of the female sex hormone estrogen is thought to be highly significant to epilepsy of puberty.;This study was designed to provide information about the role of estrogen and ionized calcium in seizures during the menstrual cycle of gynaecologically mature female epileptics. The study sample comprised 16 female epileptics ages 18 to 40 years resident in southwestern Ontario. …

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Alterations Of Gene Expression Induced By Temperature And Thyroid Hormone In Amphibian Cell Cultures, Cheryl Anne Ketola Jan 1986

Alterations Of Gene Expression Induced By Temperature And Thyroid Hormone In Amphibian Cell Cultures, Cheryl Anne Ketola

Digitized Theses

Primary epidermal cell cultures from wholly larval (tail fin) and adult (hind limb) organs were incubated briefly at temperatures between 22 and 36.5(DEGREES)C. At 32, 34 and 36.5(DEGREES)C, epidermal cell cultures from tail fin and hind limb depressed the synthesis of 'control' proteins and synthesized a novel heat shock protein (HSP) of 65 kd (pI 6.7-6.8); synthesis of an additional HSP (M(,r) = 25 kd) was detected only at 36.5(DEGREES)C. The synthesis of these HSPs is transient as control protein synthesis is virtually restored 4 hr after returning the cultures to the control (22(DEGREES)C) temperature. The results indicate that these …

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Biochemistry And Assembly Of The Regular Surface Array Of Aquaspirillum Serpens Mw5, Marion Leah Kist Jan 1986

Biochemistry And Assembly Of The Regular Surface Array Of Aquaspirillum Serpens Mw5, Marion Leah Kist

Digitized Theses

The regularly-structured surface array of the Gram-negative bacterium, Aquaspirillum serpens MW5, consists of two layers of hexagonally-arranged subunits which, together, produce a complex and linear surface pattern. The components of the structure were isolated and identified as proteins and the biochemical and in vitro assembly properties of these proteins were examined.;The array was removed from cell envelopes and dissociated by treatment with 6 M urea. The isolated surface components reassembled onto outer membrane and self-assembled into planar sheets in vitro. Both assemblies required the presence of calcium or strontium. Image analysis of the self-assembled sheets showed that they were highly …

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Distribution And Metabolism Of Polyisoprenoid Alcohols In Plants, Ravi Kothapalli Jan 1986

Distribution And Metabolism Of Polyisoprenoid Alcohols In Plants, Ravi Kothapalli

Digitized Theses

The phosphorylated derivatives of (alpha)-unsaturated polyisoprenoid alcohols (polyprenols) are obligatory intermediates in the biosynthesis of cell wall glycans in bacteria, whereas (alpha)-saturated polyisoprenoid alcohols (dolichols) are essential intermediates in the biosynthesis of asparagine-linked glycoproteins in eucaryotic organisms. Although a number of polyisoprenoid alcohols from plants have been characterized, there is much more to learn about the distribution, metabolism and function of polyisoprenoid alcohols in plants.;Polyisoprenoid alcohols were isolated from seeds of different plant species and purified by high pressure liquid chromatography. The presence of dolichols in dicotyledonous seeds, and both dolichols and polyprenols in monocotyledonous seeds was established by nuclear …

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The Analysis And Prediction Of Seed Dispersal Patterns, Stephen James Mccanny Jan 1986

The Analysis And Prediction Of Seed Dispersal Patterns, Stephen James Mccanny

Digitized Theses

Spatial patterns of sibling plants constitute unique microcosms for the study of plant population biology. I have developed the thesis that aspects of seed dispersal patterns may be predicted from a knowledge of parent plant architecture and that seed dispersal patterns may be used, in turn, to predict patterns of surviving offspring. Individuals from six distinct biotypes of Panicum miliaceum L. (Poaceae) were grown in three crop environments: oats, soybeans, and corn. Seed dispersal patterns and patterns of mature offspring were mapped using a contiguous grid of triangular sections. Plant architecture was described in terms of the spatial positions of …

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In Vivo Regulation Of Transcription Of The Escherichia Coli Rna Polymerase Genes Rpo(B) And Rpo(C), Geoffrey Ralling Jan 1986

In Vivo Regulation Of Transcription Of The Escherichia Coli Rna Polymerase Genes Rpo(B) And Rpo(C), Geoffrey Ralling

Digitized Theses

The transcriptional control of two genes rpoB and rpoC encoding b and b', the major protein subunits of E. coli RNA polymerase, was examined in vivo. Restriction fragments from the rplKAJLrpoBC cluster of genes were fused to a lacZ gene carried on a lambda phase vector. The transcriptional activity of each cloned fragment was examined by measuring the b-galactosidase level in a lysogen carrying a transcriptional fusion phage. Two strong promoters, rplKp and rplJp, were identified along with a weak promoter, rplLp. A transcriptional attenuator, atn, located between rplL and rpoB, terminated 60 percent of transcription reading through it regardless …

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The Reproductive Physiology Of Brook Charr (Salvelinus Fontinalis, Mitchill) From Neutral And Acidic Lakes In Northern Ontario, Robert Jean Roy Jan 1986

The Reproductive Physiology Of Brook Charr (Salvelinus Fontinalis, Mitchill) From Neutral And Acidic Lakes In Northern Ontario, Robert Jean Roy

Digitized Theses

This study tested the hypothesis that the reproductive physiology of brook charr (Salvelinus fontinalis) differed between acidic and neutral lakes. Charr were collected from neutral (pH > 6.5) and acidic (pH < 6.5) lakes in the Sault Ste Marie and Blind River areas of Northern Ontario from June to November of 1981 to 1983. Female brook charr from neutral lakes initiated exogenous vitellogenesis in July. Charr from acidic lakes began exogenous vitellogenesis approximately one month later than neutral lake charr. Charr from acidic lakes had fewer yolky oocytes and more oil droplet oocytes than those from neutral lakes in July and August. However, oocyte development was accelerated from September onwards and the abundance of all oocyte stages was the same in charr from acidic and neutral lakes by October. Charr from the acidic lakes produced significantly more mature ova than charr from neutral lakes, but the average weight and diameter of the ova were decreased. Plasma estrogen and vitellogenin levels did not differ among charr from acidic and neutral lakes. Male brook charr from neutral lakes initiated rapid spermatogenesis in June, as measured by the increase in spermatocyte and spermatozoa cyst diameter and percent of testis area. Charr from acidic lakes initiated rapid spermatogenesis and spermiogenesis in July, one month later than charr from the neutral lakes. The rate of spermatogenesis increased in charr from acidic lakes in September, so by October, the quantity of spermatozoa in their testes was the same as in charr from neutral lakes. Histological evidence indicates that charr from acidic lakes did not spawn in October and November, as did those in neutral lakes. Spawning activity was observed in the neutral lakes by mid-October, but spawning still had not occurred by mid-November in the acidic lakes. This study is the first to demonstrate a change in the reproductive physiology of fish due to pH under natural conditions.

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Life History Variation In Artemisia Campestris On A Lake Huron Sand Dune System, Anne Felicite Stairs Jan 1986

Life History Variation In Artemisia Campestris On A Lake Huron Sand Dune System, Anne Felicite Stairs

Digitized Theses

Both monocarpic and polycarpic phenotypes occur in populations of Artemisia campestris growing on the sand dunes at Pinery Provincial Park, Ontario. Populations in three habitats differing in seral age, vegetation cover, vegetation type and proximity to the lake were selected for study. The distribution of phenotypes within and among populations, genetic control of the character and the relationship between number of reproductive events and age-specific survivorship were examined. Emergence patterns, fecundity, impact of herbivores, rosette diameter and growth patterns were also investigated.;Established plants within populations were mapped and tagged. Permanent plots were established to study seedling recruitment and to augment …

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Functional Organization Of The Paramedian Reticular Nucleus Of The Cat, Konstantin Volod Elisevich Jan 1986

Functional Organization Of The Paramedian Reticular Nucleus Of The Cat, Konstantin Volod Elisevich

Digitized Theses

The functional organization of the PRN of the cat medulla was studied in light of its potential role as an integrator of postural and cardiovascular afferent information. Neurons in a large number of afferent sites including the cerebellar deep nuclei, vestibular, accessory oculomotor and solitary nuclei, superior colliculus, bulbar reticular formation, cerebral cortex and spinal cord were retrogradely labeled with HRP following injection of the dorsal and ventral PRN. Collateral axonal projections of PRN neurons were studied with fluorescence histochemistry focusing on their cerebello- and spinopetal connections. About 50% of PRN axons projecting to the ipsilateral anterior cerebellar lobe had …

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Diffusion Via Cell-To-Cell Membrane Channels, Richard Gregory Safranyos Jan 1986

Diffusion Via Cell-To-Cell Membrane Channels, Richard Gregory Safranyos

Digitized Theses

Cell-to-cell (or gap junctional) membrane channels allow the direct movement of molecules from the cytoplasm of one cell to the cytoplasm of adjacent cells. While functioning to maintain homeostasis among cells in a tissue, these channels may also function in the transmission of signals involved in pattern formation in development. This thesis investigates the properties of cell-to-cell membrane channels in a developing tissue.;The rates of diffusion for the intercellular movement of fluorescent tracers, expressed as (D(,e)), have been measured among the developing epidermal cells of a larval beetle, Tenebrio molitor L. The spread of injected tracers in this monolayer was …

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Control Of Movement Initiation In Humans, Susan Holly Brown Jan 1986

Control Of Movement Initiation In Humans, Susan Holly Brown

Digitized Theses

The purpose of this study was three-fold: (1) does agonist activity (Ag1) duration remain constant over a wide range of movement amplitudes? (2) can Ag1 be modified by peripheral feedback? and (3) what is the precise relationship between Ag1 and the acceleratory phase of the movement?;In the first set of experiments, subjects performed 5 to 50 degree step-tracking movements about the elbow. In all subjects, small movements (5-20 deg) were initiated by short duration Ag1 bursts (70-80 ms) while large movements (40-50 deg) were initiated by long duration bursts (140-150 ms). The increased Ag1 duration resulted from a second peak …

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Characteristics And Control Of Bilateral Arm Movement In Humans, Dhia Abdel-Hadi Al-Senawi Jan 1986

Characteristics And Control Of Bilateral Arm Movement In Humans, Dhia Abdel-Hadi Al-Senawi

Digitized Theses

This study deals with the following questions: (1) How precisely are movement properties matched for the two arms? (2) Is matching of movements of the two arms affected by visual information? (3) Are movements of one arm affected by kinesthetic information arising from the contralateral arm? (4) Does alteration in the motor performance of one arm affect movement performance in the other arm?;During experiments, subjects grasped a vertical rod attached to a horizontal manipulandum bar. The subject's shoulder was abducted to 90 deg. The manipulandum bar was pivoted above the subject's elbow. Subjects made step-tracking flexion/extension movements about the elbow. …

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Asymptotic Error Rates Of Classification Procedures When The Response Variable Is Ordinal, Martha Karen Campbell Jan 1986

Asymptotic Error Rates Of Classification Procedures When The Response Variable Is Ordinal, Martha Karen Campbell

Digitized Theses

When outcome is ordinal, it would be expected that classification procedures which assume ordering will be superior to classification procedures which do not assume ordering. The objective of this research was to quantify this advantage in terms of reduced classification errors. The assumptions of ordinality of y and multivariate normality of x were imposed. The problem was approached geometrically. Equations were derived to express the asymptotic error rate of a classification procedure in terms of the deviation of the estimated classification boundaries from Fisher's optimal boundaries. The asymptotic relative efficiency of two procedures was defined in terms of asymptotic classification …

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Factors Affecting The Prevalence Of Herpes Simplex Virus Type 2 Antibody: A Seroepidemiologic Survey, Joanne Chiavetta Jan 1986

Factors Affecting The Prevalence Of Herpes Simplex Virus Type 2 Antibody: A Seroepidemiologic Survey, Joanne Chiavetta

Digitized Theses

A cross-sectional survey was carried out in Toronto, Canada between 1978 and 1980 with the objective of identifying the contraceptive, sexual and socioeconomic factors associated with antibody evidence of HSV-2 infection. A stratified random sampling method was used to obtain men and women from diverse socioeconomic areas of the city. A door-to-door survey was carried out in which persons between the ages of 35 and 50 were interviewed and a blood sample drawn. The sera were analyzed using a radioimmunoassay method for herpes simplex virus (HSV) type-specific and crossreacting antibodies. Of 1,220 persons invited to participate, 957 (78.4%) completed interviews. …

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