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Consumption Of Aquatic Plants By The West Indian Manatee, Kay Etheridge, G. B. Rathbun, J. A. Powell, H. I. Kochman Jan 1985

Consumption Of Aquatic Plants By The West Indian Manatee, Kay Etheridge, G. B. Rathbun, J. A. Powell, H. I. Kochman

Biology Faculty Publications

Because manatees (Trichechus manatus) are large aquatic herbivores they have often been considered as potential control agents for aquatic plants. Several problems are associated with this concept, and a major one has been the gap in knowledge concerning food consumption rates of manatees. We estimated food consumption by measuring chews per unit time, chews per amount of food consumed, and time spent chewing food. Data were collected on captive manatees of various sizes and used to construct regression equations that predict consumption rates based on body size. Time budget data were obtained by radiotelemetry of free-ranging animals. Estimates of …


Autumnal Bird Migration Over The Windward Caribbean Islands, Timothy C. Williams , '64 Jan 1985

Autumnal Bird Migration Over The Windward Caribbean Islands, Timothy C. Williams , '64

Biology Faculty Works

No abstract provided.


Gametogenesis En Chthonerpeton Indistinctum (Gymnophiona: Typhlonectidae), Rafael O. De Sá, Nibia Berois Jan 1985

Gametogenesis En Chthonerpeton Indistinctum (Gymnophiona: Typhlonectidae), Rafael O. De Sá, Nibia Berois

Biology Faculty Publications

RESUMEN:

Histológicamente, las gónadas de Chthonerpeton indistinctum son similares a las ya descritas para otras especies del orden Gymnophiona. Los lóbulos testiculares se hallan compartimentados en unidades estructurales denominadas lóculos. La espermatogénesis ocurre en cistos sincrónicos de células germinales. Durante la espermiogénesis se identifican cuatro estados consecutivos de desarrollo: 1) cistos de espermátidas redondeadas; 2) cistos de espermátidas arrifionadas; 3) cistos de espermátidas bastoniformes y 4) espermátidas en ramillete.

El análisis histológico de los ovarios mostró la presencia de tres estados en la maduración de los folículos ováricos. Estas etapas pueden ser identificadas de acuerdo a: 1) ubicación del folículo …


Community Ecology, Robert K. Rose, Elmer C. Birney Jan 1985

Community Ecology, Robert K. Rose, Elmer C. Birney

Biological Sciences Faculty Publications

COMMUNITIES with Microtus tend to be structurally simple, usually grasslands or tundra, and to have no more than two species of Microtus and rarely more than six species of small mammals. Microtus often dominates both numerically and in total small mammal biomass, especially at higher latitudes. The small mammal community is most influenced by Microtus through its fluctuations in density, and thus also in biomass, by its relatively high level of diurnal activity, and by its year-round activity. Other species of small mammals may be adversely affected because Microtus usually is larger and behaviorally dominant and also because the mere …


Recruitment Patterns In Young French Grunts, Haemulon Flavolineatum (Family Haemulidae), At St. Croix, Virgin Islands., William N. Mcfarland, E. B. Brothers, John C. Ogden, Myra J. Shulman, E. L. Bermingham, N. M. Kotachian-Prentiss Jan 1985

Recruitment Patterns In Young French Grunts, Haemulon Flavolineatum (Family Haemulidae), At St. Croix, Virgin Islands., William N. Mcfarland, E. B. Brothers, John C. Ogden, Myra J. Shulman, E. L. Bermingham, N. M. Kotachian-Prentiss

Integrative Biology Faculty and Staff Publications

No abstract provided.


A Macrofaunal Survey Of Three Contrasting Habitats Of The Littoral Zone In Cedar Lake, Illinois, Laura L. Holt Jan 1985

A Macrofaunal Survey Of Three Contrasting Habitats Of The Littoral Zone In Cedar Lake, Illinois, Laura L. Holt

Master's Theses

No abstract provided.


The Significance Of Hypovolemia In Dehydrational Death In Anurans, Peter Blair Kimmel Jan 1985

The Significance Of Hypovolemia In Dehydrational Death In Anurans, Peter Blair Kimmel

Dissertations and Theses

The importance of hypovolemia in dehydrational death was assessed in two anuran species. Xenopus laeyis, a species which experiences a significant reduction in circulating plasma volume with dehydration, was used to evaluate the role of sympathetic reflex compensation in hypovolemia. Adrenergic blockade with propranolol or phenoxybenzamine produced no significant reduction in dehydration tolerance in this species, although β-blockade with propranolol appeared to have a minor effect. The role of hypovolemic shock in the terminal circulatory collapse that precedes death in dehydrating anurans was investigated in the toad, Bufo marinus. The activity of lysosomal proteinases (cathepsins) was used as an indicator …


The Analysis And Use Of Methodologies For The Study Of The Diets Of Long-Eared Owls From Three Environments In North Central Oregon, John M. Barss Jan 1985

The Analysis And Use Of Methodologies For The Study Of The Diets Of Long-Eared Owls From Three Environments In North Central Oregon, John M. Barss

Dissertations and Theses

Part I of this study presents a procedure for standardization of pellet analysis methodologies which improves estimation of prey biomass and determines the number of pellets needed to estimate prey diversity indices. The procedure was developed to provide a simple, easily replicated methodology for the study of pellets which also retains maximal data recorded from pellet analysis. A sample size of ten Long-eared Owl pellets was found adequate to calculate diversity indices with no significant loss of accuracy when compared to total pellets recovered from beneath a roosting site. Analysis of the total sample of pellets from a specific roost …


Seasonal Responses Of Filtration Rates To Temperature, Oxygen Availability, And Particle Concentration Of The Freshwater Clam, Musculium Partumeium (Say), Albert J. Burky, Richard B. Benjamin, Denis G. Conover, Jennifer Detrick Jan 1985

Seasonal Responses Of Filtration Rates To Temperature, Oxygen Availability, And Particle Concentration Of The Freshwater Clam, Musculium Partumeium (Say), Albert J. Burky, Richard B. Benjamin, Denis G. Conover, Jennifer Detrick

Biology Faculty Publications

Seasonal filtration rates of a pond population of the freshwater pisidiid clam, Musculium par­tumeium (Say), were assessed by measuring the clearance of 2.02 µ.m latex beads from suspension and expressed in terms of FR = a(AFDW}b where FR = filtration rate (ml H20 · hr- 1 ) , AFDW = mg ash-free dry weight of a whole clam and "a" and "b" are constants. The a-values ( = FR of a 1-mg AFDW clam} vary seasonally with the highest rates corresponding to periods of maximum growth and reproduction in the spring and fall. Changes in "b" reflect the influence of …


Comparative Study Of Lactate Dehydrogenase Activity In Diving And Nondiving Reptiles, Dennis A. Baeyens, Deborah Bursey, Robert Rountree Jan 1985

Comparative Study Of Lactate Dehydrogenase Activity In Diving And Nondiving Reptiles, Dennis A. Baeyens, Deborah Bursey, Robert Rountree

Journal of the Arkansas Academy of Science

The properties of lactate dehydrogenase (LDH) were examined in two snake species and one turtle species. The snakes used in the study were the semi-aquatic Nerodia rhombifera and the terrestrial Elaphe obsoleta, while Pseudemys scripta represented the turtle species. Our purpose was to compare the LDH activity of nondiving reptiles (Nerodia and Elaphe) with that of the well established diver Pseudemys. The kinetic properties of LDH and its susceptibility to inhibition by elevated pyruvate concentrations were investigated in the brain and heart of the three species. Brain and heart were chosen because they are highly aerobic tissues and therefore should …


Repair Of Lethal Damage Induced In A Hamster X Amphibian Hybrid Tissue Culture Cell Line By Ultraviolet Light And Gamma Ray, Susan Kulp, Ann Page, H. Gaston Griggs Jan 1985

Repair Of Lethal Damage Induced In A Hamster X Amphibian Hybrid Tissue Culture Cell Line By Ultraviolet Light And Gamma Ray, Susan Kulp, Ann Page, H. Gaston Griggs

Journal of the Arkansas Academy of Science

A hybrid cell line was formed by fusing cells from two established vertebrate tissue culture cell lines (V79B1 hamster and A84 Xenopus), which were known to differ substantially in resistance to some radiation-induced lesions and in associated repair potential. Ultraviolet and gamma ray dose-survival relations were then determined and analyzed for the three cell lines, primarily to compare the radiosensitivity (Do dose) of the hybrid line with that of each parental line for each radiation. Further experimentation was conducted to determine the extent to which observed differences in these Do doses could be attributed to interactions of the combined parental …


Morfología Y Funciones Del Conducto De Müller De Chthonerpeton Indistinctum (Reinhardt Y Lutken, 1862) (Amphibia: Gymnophiona) En Relación Con Los Mecanismos Reproductivos De La Especie, Nibia Berois, Rafael O. De Sá Jan 1985

Morfología Y Funciones Del Conducto De Müller De Chthonerpeton Indistinctum (Reinhardt Y Lutken, 1862) (Amphibia: Gymnophiona) En Relación Con Los Mecanismos Reproductivos De La Especie, Nibia Berois, Rafael O. De Sá

Biology Faculty Publications

El orden Gymnophiona comprende anfibios ápodos, ciegos, de hábitos cavícolas y acuáticos. Como consecuencia de estos hábitos resulta muy difícil su colecta, lo cual redunda en un escaso conocimiento de la biología del orden y sobre las relaciones filogenéticas del mismo.

Una de las características más particulares del grupo se refiere a la modalidad reproductora, ya que aproximadamente el 50% de las especies presentan viviparidad y la totalidad de ellas tienen fecundación interna. Es por esta razón que el estudio del aparato reproductor ha sido encarado por diversos autores, en especial por Wake (1968, J. Morphol. 126: 291) con una …


Bionomics Of Culicoides Spp. (Diptera: Ceratopogonidae) From A Coastal Georgia Barrier Island, George J. Magnon Jan 1985

Bionomics Of Culicoides Spp. (Diptera: Ceratopogonidae) From A Coastal Georgia Barrier Island, George J. Magnon

College of Graduate Studies: Theses & Dissertations (1964–2006)

The seasonal abundance of adult Culicoides spp. on a coastal Georgia barrier island was determined during a 20-month period, September 1983 through May 1985 by CO2-baited CDC miniature light traps and sticky cylinder traps.

A total of 220,670 adult biting midges representing nineteen species and including the first report of C. loughnani Edwards in Georgia was collected. Culicoides furens (Poey), C. hollensis (Melander and Brues), and C. melleus (Coquillett) were the most abundant. Culicoides furens was abundant from early spring to late fall. Culicoides hollensis and C. melleus were bimodal with spring and fall abundance, but C. melleus …


Corticocortical Projections Of A Visually Responsive Area In The Cat Brain, Joseph Mcgrath Jan 1985

Corticocortical Projections Of A Visually Responsive Area In The Cat Brain, Joseph Mcgrath

Journal of the Arkansas Academy of Science

The Clare-Bishop (CB) area bears the name of the investigators who first (1954) demonstrated a cortical area in the cat brain located along the lateral aspect of the middle suprasylvian gyrus which responded electrophysiologically to both optic nerve and striate cortex (area 17) stimulation. More recent studies of CB or the lateral suprasylvian (LS) area have supported its role in visual and/or oculomotor functions. Silver degeneration methods were undertaken to clarify some of the corticocortical connections of this cortical region. The data accumulated provides a morphological basis in support of the CB area's role in visual and/or oculomotor activities


The Effect Of Bilateral Adrenalectomy On The Electrocardiogram Of Meriones Unguiculatus, Jeff A. Brown Jan 1985

The Effect Of Bilateral Adrenalectomy On The Electrocardiogram Of Meriones Unguiculatus, Jeff A. Brown

Honors Theses

The effects of adrenalectomy on the heart rate and electrical potentials of the heart of the Mongolian gerbil were studied (using an EKG) in an attempt to determine in hyperkalemia is the cause of its short survival time following adrenal ablation.


The Distribution Of The Ctenophore, Mnemiopsis Leidyi (A. Agassiz), In A Vertical Thermal Gradient, James J. Leder Iii Jan 1985

The Distribution Of The Ctenophore, Mnemiopsis Leidyi (A. Agassiz), In A Vertical Thermal Gradient, James J. Leder Iii

Honors Theses

The distribution of organisms in an estuary is affected by a plethora of environmental factors. The ctenophore, Mnemiopsis leidyi, is found to exists over a wide range of these factors, temperature and salinity in particular, allowing it to occupy the estuary year round and make use of low salinity areas unavailable to most marine organisms.


Reproductive Biology Of Thamnophis Sauritus Sackenii (Kennicott) (Reptilia:Serpentes:Colubridae) From East-Central Florida, Steven. Myers Jan 1985

Reproductive Biology Of Thamnophis Sauritus Sackenii (Kennicott) (Reptilia:Serpentes:Colubridae) From East-Central Florida, Steven. Myers

Retrospective Theses and Dissertations

Peninsula ribbon snakes, Thamnophis sauritus sackenii, were collected for 14 months. Of 90 individuals collected and examined, 42 were females, 29 were males, and 19 were neonates. Females had a larger body length than did males. The smallest, sexually mature female had a snout-vent length of 428 mm. Mating occurred from March through May. Parturition occurred from June through October. Vitellogenesis began in spring and ovulation occurred between April and May. Spermatogenic activity occurred from August through December and testes were regressed during other months.


A Phylokaryotypic Evaluation Of The Genus Tursiops (Family Delphinidae), Melissa Kay Estes Jan 1985

A Phylokaryotypic Evaluation Of The Genus Tursiops (Family Delphinidae), Melissa Kay Estes

Dissertations and Theses

In an attempt to correlate genetic data with possible species delineation, this study investigates the presence of chromosomal variants between the North Atlantic bottle nose dolphin, Tursiops truncatus, and the North Pacific bottle nose dolphin, T. gilli. Blood samples were obtained from oceanaria in the United States. Location of capture was correlated with karyotype to compare chromosome morphology with geographic range.


Estructura Del Ovario De Chthonerpeton Indistinctum (Reinhardt Y Lutken, 1862) (Amphibia: Gymnophiona) Durante La Gestación, Rafael O. De Sá, Nibia Berois Jan 1985

Estructura Del Ovario De Chthonerpeton Indistinctum (Reinhardt Y Lutken, 1862) (Amphibia: Gymnophiona) Durante La Gestación, Rafael O. De Sá, Nibia Berois

Biology Faculty Publications

La morfología e histología del ovario para varias especies del orden Gymnophiona ha sido reportada por Wake (1968, J. Morphol. 126, 291) y para C. indistinctum por los autores (1984, XXIV Reunión de Comunicaciones, Soc. Zool. Uruguay).

Continuando con los estudios sobre el aparato genital de esta especie vivípara, se presenta ahora la estructura del ovario durante la gestación.

Se procesaron con fines histológicos, ovarios de dos hembras grávidas colectadas en las costas de los Dep. Montevideo y San José en abril, 1983. El número de ejemplares trabajados es muy reducido dado lo difícil que resulta su colecta …


Survey Of Intestinal Parasites In Zoo Populations Of Two Central Illinois Zoos And Study Of Current Anti-Parasitic Drugs And Prophylactic Techniques, Verona A. Barr Jan 1985

Survey Of Intestinal Parasites In Zoo Populations Of Two Central Illinois Zoos And Study Of Current Anti-Parasitic Drugs And Prophylactic Techniques, Verona A. Barr

Master's Theses

No abstract provided.


The De Novo Biosynthesis Of Cytokinins By Cell-Free Extracts Of Baker's Yeast, Debra A. Tonetti Jan 1985

The De Novo Biosynthesis Of Cytokinins By Cell-Free Extracts Of Baker's Yeast, Debra A. Tonetti

Master's Theses

No abstract provided.


A Survey Of Cattle Ectoparasites And A Study Of Psoroptic Mange In Southeast Georgia, Anne-Marie A. Callcott Jan 1985

A Survey Of Cattle Ectoparasites And A Study Of Psoroptic Mange In Southeast Georgia, Anne-Marie A. Callcott

College of Graduate Studies: Theses & Dissertations (1964–2006)

A comparison of traditional scrapings vs. a vacuum cleaner method of collecting cattle ectoparasites determined the vacuum method to be as efficient as the scraping method for collecting Psoroptes ovis, and possibly as effective for collecting Bovicola bovis.

In a survey of cattle ectoparasites in southeast Georgia, using the vacuum method, B. bovis were collected from cattle in a sales barn with an average of 15% parasitism from January 21 to March 18, 1985. Private herds sampled by the vacuum method, showed no ectoparasites. Cattle grubs (Hypoderma lineatum) were found on cattle in a sales barn from …


X-Ray Microanalysis In Cryosections Of Natively Frozen Paramecium Caudatum With Regard To Ion Distribution In Ciliates, M. Schmitz, R. Meyer, K. Zierold Dec 1984

X-Ray Microanalysis In Cryosections Of Natively Frozen Paramecium Caudatum With Regard To Ion Distribution In Ciliates, M. Schmitz, R. Meyer, K. Zierold

Scanning Electron Microscopy

Cells of Paramecium caudatum were shock-frozen without pretreatment for cryoultramicrotomy and freeze-dried for subsequent X-ray microanalysis. Na, Mg, P, S, Cl, K, and Ca were detected in different amounts in several subcellular compartments. In particular, calcium was localized below the cell surface (pellicle). Trichocysts were found to contain significant amounts of Na in their base but not in the tip. Na, Mg, P, S, Cl, K, Ca were found in electron dense deposits within the lumen of the contractile vacuole. A small K concentration was found in the cytoplasm and in the mitochondria. X-ray microanalysis of the element distribution in …


Resource Partitioning In Seven Species Of Sympatric Intertidal Chitons (Mollusca: Polyplacophora), Richard D. Piercy Dec 1984

Resource Partitioning In Seven Species Of Sympatric Intertidal Chitons (Mollusca: Polyplacophora), Richard D. Piercy

Loma Linda University Electronic Theses, Dissertations & Projects

Space (intertidal height and location/exposure on the rock surface), and food {gut contents) were partitioned among 7 species of sympatric intertidal chitons: Mopaliidae - Mopalia hindsii, M. ciliata, ~· lignosa, M. muscosa, and Katharina tunicata; and Ischnochitonidae - Tonicella lineata and Cyanoplax dentiens. Species distribution relative to intertidal height (-0.3m to +0.9m) showed significant differences. M. hindsii, ~· ciliata, M. lignosa, and T. lineata preferred slopes or undersides of rocks while ~· muscosa, K. tunicata, and c. dentiens occurred on the top horizontal surfaces or in more exposed habitats. Chitons differed significantly in their associations with Lithothamnion, macrophytic algae, Ulva, …


Wave-Length Dispersive Microprobe Analysis Of Coated Samples Of Bulk Tissues, C. Ward Kischer, Thomas M. Teska Nov 1984

Wave-Length Dispersive Microprobe Analysis Of Coated Samples Of Bulk Tissues, C. Ward Kischer, Thomas M. Teska

Scanning Electron Microscopy

Hypertrophic scars contain highly pleomorphic cells, including many from the erythrocytic series which have been extravasated. The conventional visual mode of SEM cannot distinguish the cell types with certainty except in the case of typical biconcave disc-shaped erythrocytes. Microprobe elemental analysis might be used to differentiate one type from another on the basis of iron and possibly phosphorus (for nucleated cells). Using coated specimens (gold or gold-palladium) precludes simultaneous visual mode SEM with EDX because of energy line interference with phosphorus and other elements. However, wave-length dispersive analysis offers minimal or no interference, and a coated specimen offers the use …


Intracellular Localization Of Heavy Metals In Yeast By X-Ray Microanalysis, Ljerka Kunst, Godfried M. Roomans Nov 1984

Intracellular Localization Of Heavy Metals In Yeast By X-Ray Microanalysis, Ljerka Kunst, Godfried M. Roomans

Scanning Electron Microscopy

The intracellular localization of heavy metals in yeast cells was studied by means of energy-dispersive X-ray microanalysis. The yeast, Saccharomyces cerevisiae, was pretreated with phosphate and then loaded with different metal ions, by suspending the cells in salt solutions (Ni, Zn, Cd, Pb, Al and Cr). For the analysis, the cells were embedded in gelatin, rapidly frozen, and thin cryosections were cut on a dry knife.

A considerable uptake of divalent cations by the yeast cells was found to occur. The cations were bound to the polyphosphate granules localized in or close to the cell vacuoles. Immediately after phosphate …


Alterations Of The Intracellular Water And Ion Concentrations In Brain And Liver Cells During Aging As Revealed By Energy Dispersive X-Ray Microanalysis Of Bulk Specimens, Gy. Lustyik, I. Zs.-Nagy Nov 1984

Alterations Of The Intracellular Water And Ion Concentrations In Brain And Liver Cells During Aging As Revealed By Energy Dispersive X-Ray Microanalysis Of Bulk Specimens, Gy. Lustyik, I. Zs.-Nagy

Scanning Electron Microscopy

Age dependence of the intracellular concentrations of monovalent ions (Na+, K+ and Cl-) was examined in 1, 11 and 25-month-old rat brain and liver cells by using energy dispersive X-ray microanalysis. The in vivo concentrations of Na+, K+ and Cl- ions were calculated from two different measurements: The elemental concentrations were measured in freeze-dried tissue pieces, and the intracellular water content was determined by means of a recently developed X-ray microanalytic method, using frozen-hydrated and fractured bulk specimens as well as subsequent freeze-drying.

All the single monovalent ion concentrations and consequently, also the total monovalent ion content showed statistically significant …


Scanning Electron Microscopy Of The Lateral Ventricle Of The Pigeon Brain, P. Mestres, K. Rascher, J. D. Delius Nov 1984

Scanning Electron Microscopy Of The Lateral Ventricle Of The Pigeon Brain, P. Mestres, K. Rascher, J. D. Delius

Scanning Electron Microscopy

Adult pigeons of both sexes were used for this study. Depending upon the distribution of various surface profiles, for example cilia, microvilli and blebs, ependymal areas with differing surface patterns were distinguished in the lateral ventricle. The topographical locations of these areas with respect to the underlying forebrain nuclei were determined in accord with the atlas of Karten and Hodos (1967). The medial surface (A) of the ventricle was much more densely ciliated than the lateral surface (B). There did not appear to be any correlation between a given surface pattern and a specific type of underlying nervous tissue. Comparison …


Ultrasonic Microdissection Of Rat Cerebellum For Scanning Electron Microscopy, C. E. Arnett Iii, F. N. Low Oct 1984

Ultrasonic Microdissection Of Rat Cerebellum For Scanning Electron Microscopy, C. E. Arnett Iii, F. N. Low

Scanning Electron Microscopy

The cerebelli of rats were initially fixed with aldehydes (modified Karnovsky's fixative; 503 mOsM/L) by cardiac perfusion. Blocks of tissue were razor-cut, usually longitudinal to folia, and immersed in the same fluid for 2-4 hours. Three separate methods of treatment followed: (1) immersion in 1% aqueous boric acid, or (2) in 2% phosphate buffered OsO4 followed by boric acid or (3) in an 8/2 mixture of boric acid and OsO4. After 18-48 hours immersion the blocks were dehydrated in ascending grades of acetone. They were then exposed to ultrasound in 100% acetone at frequencies of 80 kHz …


Use Of Scanning Electron Microscopy To Study Structural-Functional Relationships In Normal And Diseased Platelets, J. C. Mattson Oct 1984

Use Of Scanning Electron Microscopy To Study Structural-Functional Relationships In Normal And Diseased Platelets, J. C. Mattson

Scanning Electron Microscopy

This paper reviews the contribution of scanning electron microscopy (SEM) to our understanding of platelet physiology and pathology. Observations of platelet shape changes which accompany activation and the ability to visualize and analyze platelet aggregation and adhesion in three dimensions make this experimental medium an important tool in the evaluation of healthy and diseased platelets. While SEM adds a valuable third dimension to the study of morphology and ultrastructure, its greatest contribution is realized when studies are correlated directly with light and/or transmission electron microscopic observations and with studies of functional capacity.