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The Effects Of Beach Restoration On Marine Turtles' Nesting In South Brevard County, Florida, Paul W. Raymond Jan 1984

The Effects Of Beach Restoration On Marine Turtles' Nesting In South Brevard County, Florida, Paul W. Raymond

Retrospective Theses and Dissertations

The south Brevard coast of Florida is a major nesting ground for the Atlantic loggerhead turtle (Caretta caretta). A beach restoration project was completed in the winter of 1980-81 at Indialantic and Melbourne Beach. A study was conducted to investigate the effects of beach restoration on marine turtle nesting during the summer months of 1981 and 1982. A 3.1 km restored beach study area and two control beach study areas, each 3.1 km in length and consisting of natural beach sands, were established. The entire study area (9.3 km) was monitored for nesting and non-nesting emergences (false crawls) and a …


The Isolation And Identification Of Flavonoids In Zygocactus, Jacqueline M. Wade Jan 1984

The Isolation And Identification Of Flavonoids In Zygocactus, Jacqueline M. Wade

Retrospective Theses and Dissertations

No abstract provided.


Factors That Influence Plant Species Richness On Habitat Islands Of Sand Pine Scrub, Cindy B. Connery Jan 1984

Factors That Influence Plant Species Richness On Habitat Islands Of Sand Pine Scrub, Cindy B. Connery

Retrospective Theses and Dissertations

No abstract provided.


Comparison Of Three Methods For Sampling Fishes And Macroinvertebrates In A Vegetated Wetland, B. J. Freeman, H. S. Greening, J. Douglas Oliver Jan 1984

Comparison Of Three Methods For Sampling Fishes And Macroinvertebrates In A Vegetated Wetland, B. J. Freeman, H. S. Greening, J. Douglas Oliver

Faculty Publications and Presentations

Three methods of sampling fishes, two seining methods and a drop trap method, were evaluated in heavily vegetated freshwater habitats. The portable drop trap method, which utilized a 1 x 1 m-sq. trap, collected significantly more macroinvertebrates and fish per unit area than did the seining methods. The meter square drop trap offered the additional advantages of a greater number of animals per unit effort and an integrated sample of vegetation, macroinvertebrates and fish in a given area. A 90% (s.d.= 7.4%) recovery of tagged fishes released into the traps in different habitats showed the m2 drop trap to be …


Flora And Early Secondary Succession In Wetlands Of The Lower Kanawha River Floodplain, West Virginia, Brenda Kay West Jan 1984

Flora And Early Secondary Succession In Wetlands Of The Lower Kanawha River Floodplain, West Virginia, Brenda Kay West

Theses, Dissertations and Capstones

Vegetational and floristic analyses were performed on eight wetlands undergoing early secondary succession on the Kanawha River floodplain of' West Virginia. All sites have been cleared previously and have been revegetated for 30 years or less. Vegetation was classified into ten cover types according to species composition and physiognomy. Aquatic, graminoid dominated wet meadow, shrub-wet meadow, Spiraea tomentosa dominated, Comus amomum dominated, and various early forested wetlands were among the cover types classified and surveyed. Frequency, density, dominance, and importance values were established with random plot sampling for both herbaceous and woody species. A total of 262 species distributed among …


Activation Of B Lymphocytes By Monovalent Anti-Lyb-2 Antibodies, Subbarao Bondada, D. E. Mosier Jan 1984

Activation Of B Lymphocytes By Monovalent Anti-Lyb-2 Antibodies, Subbarao Bondada, D. E. Mosier

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Small resting B lymphocytes are activated when their cell surface immuno-globulin (Ig) receptors interact with specific antigen or anti-Ig antibodies. Such a receptor-ligand interaction leads to enlargement and proliferation of B lymphocytes. These activated B cells can subsequently mature into Ig-secreting cells in the presence of appropriate accessory cell signals (1-3). However, monovalent anti-Ig antibodies cannot induce B cell activation even though they can bind to the surface Ig (4-7). It has thus been concluded that membrane Ig has to be cross-linked to induce early steps in B cell activation (membrane depolarization; 8) as well as later steps (proliferation). T …


Growth Analysis Based On Degree Days, M. P. Russelle, Wallace Wilhelm, R. A. Olson, James F. Power Jan 1984

Growth Analysis Based On Degree Days, M. P. Russelle, Wallace Wilhelm, R. A. Olson, James F. Power

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Comparisons of growth analysis functions within and among experiments are often confounded by sources of variation other than those imposed by treatment. we suggest use of a temperature index, such as modified growing degree days, as the divisor in growth functions to facilitate treatment comparisons within certain experiments and to reduce the effects of differing temperature regimes among experiments on these comparisons. Three experiments were identified to provide data to analyze this new approach. Mean absolute growth rate (GR) and mean relative growth rate (RGR) were compared in two experiments with maize (Zea mays L.) conducted in eastern Nebraska. …


Endocrine Mechanisms Of Puberty In Heifers: Estradiol Negative Feedback Regulation Of Luteinizing Hormone Secretion, M. L. Day, K. Imakawa, M. Garcia-Winder, D. D. Zalesky, B. D. Schanbacher, Roger J. Kittok, J. E. Kinder Jan 1984

Endocrine Mechanisms Of Puberty In Heifers: Estradiol Negative Feedback Regulation Of Luteinizing Hormone Secretion, M. L. Day, K. Imakawa, M. Garcia-Winder, D. D. Zalesky, B. D. Schanbacher, Roger J. Kittok, J. E. Kinder

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The hypothesis that luteinizing hormone (LH) secretion in prepubertal females is responsive to estradiol negative feedback and that decreased feedback occurs as puberty approaches was tested in heifers. In the first experiment, seven heifers were maintained prepubertal by dietary energy restriction until 508 days of age (Day 0). All heifers were placed on a high-energy diet on Day 0 at which time they received no additional treatment (CONT), were ovariectomized (OVX) or were ovariectomized and subcutaneously implanted with estradiol-17β (OVX-E2). This feeding regimen was used to synchronize reproductive state in all heifers. A second experiment was performed with …


Characteristics Of A Ca++ Atpase Enzyme In The Epidermis Of Molting Blue Crabs, Callinectes Sapidus, Joanne Elizabeth Lapetina Jan 1984

Characteristics Of A Ca++ Atpase Enzyme In The Epidermis Of Molting Blue Crabs, Callinectes Sapidus, Joanne Elizabeth Lapetina

Master's Theses

Epidermal Ca++-activated ATPase was investigated in relation to the molt cycle of the blue crab, Callinectes sapidus. Premolt and postmolt tissue samples demonstrated significant elevations in Ca++-activated ATPase activity in comparison to intermolt tissue samples. These results support the suggestion that this enzyme may participate in demineralization of the old cuticle, as well as calcification of the new cuticle.

The enzyme is localized in the heavy particulate-nuclear fraction and is distinguished from mitochondrial Ca++ ATPase found in other tissues by differences in sensitivity to mersalyl acid. 0 The enzyme is most active at 49 C …


The Ontogeny And Functional Significance Of Luteinizing Hormone Releasing Hormone (Lhrh) Containing Centers Of The Brain Of The Freshwater Teleost, Xiphophorus Maculatus, Leslie R. Halpern-Sebold Jan 1984

The Ontogeny And Functional Significance Of Luteinizing Hormone Releasing Hormone (Lhrh) Containing Centers Of The Brain Of The Freshwater Teleost, Xiphophorus Maculatus, Leslie R. Halpern-Sebold

Dissertations, Theses, and Capstone Projects

The use of cytometric, immunocytochemical and radioimmunological methods has allowed the investigation of the ontogeny and functional significance of LHRH containing centers in sibling platyfish (Xiphophorus maculatus) genetically determined to reach sexual maturity at different ages and in adult fish which were hypophysectomized and given replacement therapy with gonadotropin.

There is a sequential development of three immunoreactive (ir-) LHRH centers in the brain that is directly related to stage, not age of sexual maturation. The first region to contain ir-LHRH is the nucleus olfactoretinalis (NOR). Ir-LHRH then appears in the nucleus preopticus periventricularis (NPP), followed by the nucleus lateralis tuberis …


Enteric Redmouth Disease Of Salmonids, G. L. Bullock Jan 1984

Enteric Redmouth Disease Of Salmonids, G. L. Bullock

United States Fish and Wildlife Service: Publications

Enteric redmouth disease (ERM) is a systemic bacterial infection of fishes, but is principally known for its occurrence in rainbow trout, Salmo gairdneri. The disease was first reported in the 1950's by Rucker (1966), and in recognition of that fact, the causal organism was named Yersinia ruckeri by Ewing et al. (1978). Although Wagner and Perkins (1952) described a bacterial disease that produced a red-mouth condition in rainbow trout in California and Colorado, it was caused by a different bacterium; they isolated Pseudomonas hydrophila rather than Y. ruckeri.


Two Purified Rnas Of Soil-Borne Wheat Mosaic Virus Are Needed For Infection, Yukio Shirako, Myron K. Brakke Jan 1984

Two Purified Rnas Of Soil-Borne Wheat Mosaic Virus Are Needed For Infection, Yukio Shirako, Myron K. Brakke

Department of Plant Pathology: Faculty Publications

RNAs of soil-borne wheat mosaic virus (SBWMV) from virions 281 nm, 138 nm and 92 nm long (designated here by relative lengths as 1∙0L, 0∙SL and 0∙35L, respectively), were isolated and purified by three cycles of sucrose density gradient centrifugation. Infectivity assays with these RNAs proved the bipartite nature of SBWMV, the combination of 1∙0L and either 0∙5L or 0∙35L RNAs being required for infection and for multiplication of progeny viruses. The 0∙5L RNA underwent deletion mutation, producing smaller variants with various sizes, of which 0∙4L and 0∙35L RNAs were confirmed to be functional in combination with 1∙0L RNA. The …


The Effects Of Calcium Hydroxide Treatment Of Sunflower Seeds On Ration Digestibility And Rumen Parameters In Holstein Steers, Ann C. Spearow Jan 1984

The Effects Of Calcium Hydroxide Treatment Of Sunflower Seeds On Ration Digestibility And Rumen Parameters In Holstein Steers, Ann C. Spearow

Electronic Theses and Dissertations

Digestibilities of rations containing 10% (dry matter basis) oil-type, rolled sunflower seeds treated with three levels- of calcium hydroxide were compared using .a randomized complete block design. Forty-eight Holstein steers were fed one of six completely mixed rations consisting of (DM basis) 44% corn silage, 10% chopped alfalfa hay, and 46% concentrate mix. Concentrate mixes contained: CSM = control; SCS =control+ 22% sunflower seeds; SCL = SCS + 3.5% additional limestone; SCH2, SCH4, and SCH8 = SCS + 2, 4, and 8% calcium hydroxide (% sunflower seed DM), respectively. Total rations were isonitrogeneous at approximately 16% crude protein and isocaloric …


Lentinus Edodes Colonization Of Oak Is Enhanced By Log Treatment With Methyl Bromide, Elmer L. Schmidt Jan 1984

Lentinus Edodes Colonization Of Oak Is Enhanced By Log Treatment With Methyl Bromide, Elmer L. Schmidt

Journal of the Minnesota Academy of Science

Two or more years of outdoor incubation of inoculated oak logs are required before shiitake (Lentinus edodes [Berk.] Sing.) mushrooms appear; methods to accelerate the rate of oak sapwood colonization should reduce this incubation period. Observed increased mold growth of oak sapwood fumigated with methyl bromide (MB) prompted an experiment to determine whether such treatment would enhance oak colonization by L. edodes. Red and bur oak bolts ( 1 m long) were inoculated three weeks after felling. Half of the bolts were fumigated with MB ( 100 g per m3 of space beneath a plastic tarp) for three days, then …


Physical, Chemical, And Biological Controls: Modern And Future Approaches To Mosquito Control, Max V. Meisch Jan 1984

Physical, Chemical, And Biological Controls: Modern And Future Approaches To Mosquito Control, Max V. Meisch

Journal of the Minnesota Academy of Science

Effective mosquito management depends on a blending of many techniques. The primary technologies available are physical, chemical, and biological; and their continued improved usage is demanded. Chemicals are more contemporary. Modern organic insecticides were first used in 1943 with the advent of DDT usage. The judicious use of pesticides remains imperative in control methodology. However, a program optimizing non-chemical applications offers the best method for long-term success. A systems approach is needed regardless of strategies used. Basing strategies on objectives differs according to objectives of disease, annoyance, or livestock protection. The strategy is predicated on knowledge of the biology of …


Technical Session - Panel Discussion And Questions Jan 1984

Technical Session - Panel Discussion And Questions

Journal of the Minnesota Academy of Science

No abstract provided.


Survival Strategies Of Invertebrates In Disturbed Aquatic Habitats, Rosemary J. Mackay Jan 1984

Survival Strategies Of Invertebrates In Disturbed Aquatic Habitats, Rosemary J. Mackay

Journal of the Minnesota Academy of Science

Disturbance in aquatic habitats may be caused by drought, flood , changes in temperature, and unusual or unnatural introductions of particulate or dissolved substances from the surrounding land. Aquatic invertebrates survive disturbance by moving to a refuge or alternative habitat or by having resistant or specially protected stages in the life cycle. Some invertebrates are able to exploit the richer and more available food materials that may result from the disturbance. Most species in disturbed aquatic habitats are efficient colonizers; they combine one or more survival strategies with high powers of dispersal, rapid growth rates, and characteristics of ecological generalists.


The Response Of Invertebrates In Temporary Vernal Wetlands To Altosid Sr-10 As Used In Mosquito Abatement Programs, Ronald W. Lawrenz Jan 1984

The Response Of Invertebrates In Temporary Vernal Wetlands To Altosid Sr-10 As Used In Mosquito Abatement Programs, Ronald W. Lawrenz

Journal of the Minnesota Academy of Science

Three temporary vernal wetlands on the Bayport Wildlife Management Area in eastern Washington County, Minnesota, were divided by sandbag barrier into treatment and control areas. Designated areas were treated with Altosid® SR-10 briquets at standard mosquito control rates. Invertebrate populations were monitored weekly using net sweeps, column samples, and ocular estimates.

The development of Eubranchtpus bundyi, Lyncerus sp, and Daphnia sp., the three major components of the invertebrate fauna, was delayed by as much as one week in site 47. Similar developmental lags were noted for E. bundyi populations in the treated portions of sites 6 and 32. Delay of …


Mosquito Control And Minnesota Amphibians, Tom R. Johnson Jan 1984

Mosquito Control And Minnesota Amphibians, Tom R. Johnson

Journal of the Minnesota Academy of Science

Minnesota has 19 species of amphibians. Most of these animals have habitat requirements that include natural marshes, woodland ponds, and temporary pools. Amphibians need a stable and unpolluted environment. Changes in the pH of marshes or other aquatic habitats can be detrimental to Minnesota's amphibians. Habitat loss through the draining of marshes will be especially damaging. Several questions concerning mosquito control and its effects on amphibians need to be addressed.


Minnesota's Response: The Mosquito Research Program, John Washburn, Nancy Read Jan 1984

Minnesota's Response: The Mosquito Research Program, John Washburn, Nancy Read

Journal of the Minnesota Academy of Science

The Minnesota Mosquito Research Program (MMRP) was established in September 1984 in response to a request by Governor Perpich. The Minnesota Department of Health (MDH), as the lead agency, brought together a Working Group of distinguished North American experts to discuss the problems related to mosquito research and control. This Working Group- with advice from legislators and representatives from the community, environmental groups, and state and federal agencies- made recommendations for the development of a mosquito research and control program in Minnesota.

The Working Group divided its recommendations into two areas, research and administrative structure. An extensive research program in …


Sexual Dimorphism In Species Of Raninoides (Brachyura: Raninidae) And The Status Of Raninidoides Schmitti Sawaya, 1944, Gary D. Goeke Jan 1984

Sexual Dimorphism In Species Of Raninoides (Brachyura: Raninidae) And The Status Of Raninidoides Schmitti Sawaya, 1944, Gary D. Goeke

Gulf and Caribbean Research

The frog crab Raninoides schmitti was described from São Paulo, Brazil, as closely related to R. loevis. Detailed comparison shows R. schmitti to be a junior synonym of R. loevis. Absence of information detailing sexual dimorphism of species in the genus Raninoldes contributed to the designation of a dimorphic male as a discrete taxon. Examples of sexual dimorphism within the genus Raninoides are described.


Review Of Upwelling Off The Southeastern United States And Its Effect On Continental-Shelf Nutrient Concentrations And Primary Productivity, Larry P. Atkinson, James A. Yonder, Thomas N. Lee Jan 1984

Review Of Upwelling Off The Southeastern United States And Its Effect On Continental-Shelf Nutrient Concentrations And Primary Productivity, Larry P. Atkinson, James A. Yonder, Thomas N. Lee

CCPO Publications

Gulf Stream induced upwelling occurs along the length of the southeastern United States continental shelf break. Upwelling events are produced by northward propagating Gulf Streams frontal meanders and eddies and travel northwards with these features. Meanders and eddies occur throughout the year in a period band of 2-14 days; however, resultant upwellings can affect the shelf quite differently. During fall, winter, and spring, upwelling is restricted to the outer shelf by cross-shelf density distributions, but in the summer upwelled water may penetrate across as a subsurface intrusion if aided by upwelling-favorable winds. If water does penetrate across the shelf, it …


The Epiphytic Diatom Flora Of Two Sargassum Species, Robert S. Maples Jan 1984

The Epiphytic Diatom Flora Of Two Sargassum Species, Robert S. Maples

Gulf and Caribbean Research

The epiphytic diatom flora on the brown algae Sargassum natans (L.) J. Meyer and S. fluitans Børgesen were investigated and compared. A total of 50 taxa representing 21 genera were identified. The most abundant taxa were Amphora exigua Greg., A. coffeiformis (Ag.) Kütz., Synedra fasciculata (Ag.) Kütz., Cocconeis pseudodiruptoides Foged, and Navicula ramosissima (Ag.) Cleve. Comparisons of the dominant species and diversity statistics characterizing the two samples indicated the two brown algal species supported nearly identical epiphytic diatom floras.


Distribution And Ecology Of The Synaphobranchidae Of The Gulf Of Mexico, Douglas M. Martin Jan 1984

Distribution And Ecology Of The Synaphobranchidae Of The Gulf Of Mexico, Douglas M. Martin

Gulf and Caribbean Research

Synaphobranchid eels of the Gulf of Mexico are an important part of the upper continental slope ichthyofauna, occurring most frequently between 500 and 1,500 m. Two of the four known genera (Histiobranchus and Diastobranchus) have not been reported from the Gulf. Synaphobranchidae tend to occur within a narrow range of temperatures compared to the North Atlantic synaphobranchid eels. However, distribution of these eels in the deeper parts of the Gulf appears to be correlated more to change in depth than to temperature, salinity, or dissolved oxygen. The distribution at the shallower limits of their depth range appear to …


A Review Of The Genus Clythrocerus (Brachyura: Dorippidae) In The Eastern Gulf Of Mexico With Notes On Clythrocerus Stimpsoni, Gary D. Goeke, Richard W. Heard Jan 1984

A Review Of The Genus Clythrocerus (Brachyura: Dorippidae) In The Eastern Gulf Of Mexico With Notes On Clythrocerus Stimpsoni, Gary D. Goeke, Richard W. Heard

Gulf and Caribbean Research

The four members of the dorippid crab genus Clythrocerus from the Gulf of Mexico are reviewed. The rediscovery of C. stimpsoni has allowed for the first description of the male of the species. Known previously only from the unique holotypic female, the rediscovery of C. stimpsoni is based on material from the same general area as the type-locality. Clythrocerus granulatus and C. perpusillus are reported for the first time from the Gulf of Mexico. The latter form was the most frequently collected species of Clythrocerus from the study area. Although no specimens of C. nitidus occurred in our samples, previous …


Autecology Of The Black Needlerush Juncus Roemerianus, Lionel N. Eleuterius Jan 1984

Autecology Of The Black Needlerush Juncus Roemerianus, Lionel N. Eleuterius

Gulf and Caribbean Research

Juncus roemerianus generally occupies the upper half of the intertidal plane and covers about 92% or 25,000 hectares of marsh in Mississippi. The vegetative canopy is best described as a series of disjunct and intergrading populations. Considerable phenotypic variation and differences in standing crop exist between populations. J. roemerianus has very wide environmental tolerances in comparison to all other tidal marsh angiosperms. Soil types inhabited by the rush range from very sandy to highly organic muds and peats, which may vary in the concentration of nutrient elements (nitrogen, phosphorus and potassium). Neither soil type, nutrient concentration, water content, pH nor …


Growth And Production Of The Dwarf Surf Clam Mulinia Lateralis (Say 1822) In A Georgia Estuary, Randal L. Walker, Kenneth R. Tenore Jan 1984

Growth And Production Of The Dwarf Surf Clam Mulinia Lateralis (Say 1822) In A Georgia Estuary, Randal L. Walker, Kenneth R. Tenore

Gulf and Caribbean Research

The bivalve Mulinia lateralis is a dominant member of estuarine benthos, but its presence and abundance in Georgia estuarine waters is sporadic over time. Recruitment and production was monitored from 1977 through 1981 at three inner and one outer more saline ( > 18 ppt) areas of Wassaw Sound. Until the winter of 1981, Mulinia lateralis was absent or at very low densities. Significant settlement occurred in January 1981 when densities in the outer sound reached as high as 63,000 individuals • m-2). The clam was more abundant in sandy mud (x̄ = 10,161 • m-2) than …


A Range Extension For Manayunkia Aestuarina (Bourne, 1883) (Polychaeta: Sabellidae) To The Gulf Coast Of The United States With A Review Of Previous Habitat Information, T. Dale Bishop Jan 1984

A Range Extension For Manayunkia Aestuarina (Bourne, 1883) (Polychaeta: Sabellidae) To The Gulf Coast Of The United States With A Review Of Previous Habitat Information, T. Dale Bishop

Gulf and Caribbean Research

The sabellid polychaete Manayunkia aestuarina (Bourne, 1883) is reported for the first time from the Gulf coast of the United States and from a Juncus roemerianus marsh. Individuals were collected from a brackish J. roemerianus marsh in St. Louis Bay, Mississippi, (30o22'N, 89o15'W) during the period of June 1979 to May 1980. Adults with eggs were first noted in early January and increased in number through May. Brooded young were observed from late January through May. Habitat comparisons are made between this and other North American and European populations. The present population is associated with lower …


Amphipods Of The Family Ampeliscidae (Gammaridea). Iv. Infraspecific Variation In Ampelisca Agassizi, Gary D. Goeke, Richard W. Heard Jan 1984

Amphipods Of The Family Ampeliscidae (Gammaridea). Iv. Infraspecific Variation In Ampelisca Agassizi, Gary D. Goeke, Richard W. Heard

Gulf and Caribbean Research

Considerable variation noted, in Ampelisca agassizi is herein described. The variations in the shape of the basis of pereopod 7 and the carina of urosomite I are most obyious. No relationship was found with the atypical specimens and their age, associated sediment or location.


Dingoes And Sheep In Pastoral Areas, P C. Thomson Jan 1984

Dingoes And Sheep In Pastoral Areas, P C. Thomson

Journal of the Department of Agriculture, Western Australia, Series 4

Since 1975, a long-term study of dingoes in the Fortescue River area of northern Western Australia has sought to provide the detailed information necessary to devise efficient dingo management strategies.

Dingoes have been fitted with radio-transmitter collars, then tracked and observed from a specially equipped aircraft. Their movements, breeding, hunting and social behaviour have been monitered in the rugged, spinifex-covered ironstone terrain which represents typicaldingo refuge country, and in neighbouring sheep country.

Although the pastoral and agricultural industry have long recognised the need to control dingoes to protect livestock, particularily sheep, there is little published evidence about the type of …