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Recent Advances In Laser Microprobe Mass Analysis (Lamma) Of Inner Ear Tissue, A. Meyer Zum Gottesberge-Orsulakova, R. Kaufmann Oct 1984

Recent Advances In Laser Microprobe Mass Analysis (Lamma) Of Inner Ear Tissue, A. Meyer Zum Gottesberge-Orsulakova, R. Kaufmann

Scanning Electron Microscopy

Maintenance of ionic gradients within the various fluids compartments of the inner ear requires transport active cellular systems at different locations. LAMMA analysis is ideally suited for detection of ions in microquantity on cellular levels overcoming many technical difficulties. The present paper summarizes the results of microprobe analysis obtained with laser induced mass spectrometry (LAMMA) supplemented by X-ray microprobe analysis of epithelial cell layers adjacent to the endolymphatic space (a) in the cochlear duct, (b) in the vestibular organ and (c) in the endolymphatic sac. The possible role of inner ear as well as ocular melanin in the mechanisms of …


The Ependyma Of The Cat Central Canal, With Particular Reference To Its Mitochondria-Containing Bulbs, K. Rascher, K. H. Booz, A. C. Nacimiento, E. Donauer Oct 1984

The Ependyma Of The Cat Central Canal, With Particular Reference To Its Mitochondria-Containing Bulbs, K. Rascher, K. H. Booz, A. C. Nacimiento, E. Donauer

Scanning Electron Microscopy

The ultrastructure of the ependyma in the central canal of adult cats was examined in both the scanning and the transmission electron microscopes (SEM and TEM).

The same morphological details were seen in the ependyma of the central canal as have so frequently been described in the ependyma of the brain ventricular system, for example bundles of cilia, single cilia, microvilli and occasional small cytoplasmic protrusions. The supraependymal cells and supraependymal nerve fibers found in the central canal also resembled those seen in the ventricular system.

The most striking feature of the canal ependyma were the large, spherical bodies containing …


Scanning And Transmission Electron Microscopic Studies On The Oviducts Of Pekin Ducks Fed Methyl Mercury Containing Diets, A. Balachandran, M. K. Bhatnagar, H. D. Geissinger Oct 1984

Scanning And Transmission Electron Microscopic Studies On The Oviducts Of Pekin Ducks Fed Methyl Mercury Containing Diets, A. Balachandran, M. K. Bhatnagar, H. D. Geissinger

Scanning Electron Microscopy

This study was undertaken to examine the effects of varying levels of methyl mercury (MeHg) on the ultrastructure of the surface epithelium of the oviduct of ducks. Accordingly, Pekin ducks were maintained on feed containing varying doses of (0.0; 0.5; 5.0; 15.0 ppm) of MeHg (Group I - control to IV) for 12 weeks and sacrificed. Tissue from the magnum and the shell gland regions of the oviduct was processed for scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It was found that the primary and secondary folds of these regions of the oviducts of the control and 0.5 …


Intellectual Traditions In The Life Sciences: Ii. Stereocomplementarity, Scott F. Gilbert Oct 1984

Intellectual Traditions In The Life Sciences: Ii. Stereocomplementarity, Scott F. Gilbert

Biology Faculty Works

No abstract provided.


An Ultrastructural Analysis Of The Physical Organization Of Collagenous (Type I) Matrices: One Determinant Of Urothelium Maintenance In Vitro, G. M. Hodges, C. Rowlatt, A. R. Howlett, L. K. Trejdosiewicz Sep 1984

An Ultrastructural Analysis Of The Physical Organization Of Collagenous (Type I) Matrices: One Determinant Of Urothelium Maintenance In Vitro, G. M. Hodges, C. Rowlatt, A. R. Howlett, L. K. Trejdosiewicz

Scanning Electron Microscopy

Collagenous matrices, used as cell culture substrata, can be prepared from different collagen types in a variety of forms using a range of polymerization procedures. Type I collagen has been most frequently used either as dried collagen films or hydrated collagen gels. Sheets of isolated bladder urothelium, when plated onto such matrices prepared from type I collagen by different polymerization methods (eg. air-drying; NaOH; NaCl; NH3; or NH3 followed by glutaraldehyde crosslinking) demonstrate the capability of urothelial cells to attach to a variety of differently prepared matrices irrespective of polymerization procedure. In contrast, both cell proliferation and …


The Influence Of Different Cryopreparations On The Distribution Of Ions In Bullfrog Myocard Cells, R. Meyer, M. Schmitz, K. Zierold Sep 1984

The Influence Of Different Cryopreparations On The Distribution Of Ions In Bullfrog Myocard Cells, R. Meyer, M. Schmitz, K. Zierold

Scanning Electron Microscopy

Bullfrog heart muscle trabecula are shock-frozen in liquid propane cooled by liquid nitrogen and then processed for X-ray microanalysis in two different ways: 1. Freeze-drying followed by vacuum embedding. 2. Cryoultramicrotomy and freeze-drying.

Stained sections of freeze-dried, embedded tissue exhibit detailed ultrastructure, but are useless for X-ray microanalysis. Unstained, dry cut plastic-sections are suitable for X-ray microanalysis, but the ultrastructure appears faint. Higher electron optical contrast and peak-to-background ratio of X-ray spectra are generally obtained in freeze-dried cryosections. Both preparation methods show that the X-ray spectra are influenced by the quality of cryofixation. The phosphorus/potassium ratio in nuclei increases with …


Ua66/6 Brigadoon Nature Preserve Survey Phase I, Wayne Mason, Jeff Jenkins, Kenneth Nicely, Herbert Shadowen Sep 1984

Ua66/6 Brigadoon Nature Preserve Survey Phase I, Wayne Mason, Jeff Jenkins, Kenneth Nicely, Herbert Shadowen

WKU Administration Documents

A preliminary report of an ongoing survey on the mammals, birds, vascular plants, and fungi that have been recorded at the Brigadoon Nature Preserve from November, 1983 - September, 1984.


Endometrium Cell Surface Abnormalities In The Syrian Hamster As A Result Of In Utero Exposure To Diethylstilbestrol, J. Gilloteaux, A. W. Steggles Aug 1984

Endometrium Cell Surface Abnormalities In The Syrian Hamster As A Result Of In Utero Exposure To Diethylstilbestrol, J. Gilloteaux, A. W. Steggles

Scanning Electron Microscopy

Scanning electron microscopy (SEM) was used to observe changes in the hamster endometrium cell surface following in utero pre- and/or postnatal exposure to diethylstilbestrol (DES). Some of the changes in cell surfaces are associated with alterations in cell sizes and shapes (from columnar to cuboidal and/or squamous) and in microvilli and mucous secretion. In all cases, DES treated uteri show mucosal cell surface pleomorphism, apocrine secretion and cystic accumulation of secretory material. Microvillous pleomorphism and peculiar linkages attaching one microvillus to others were investigated. Although the function and nature of such linkages is unclear, their presence seems to be more …


The Role Of The Vessels In The Growth Plate: Morphological Examination, K. Draenert, Y. Draenert Aug 1984

The Role Of The Vessels In The Growth Plate: Morphological Examination, K. Draenert, Y. Draenert

Scanning Electron Microscopy

Combined methods of light microscopy to present ossification zones by means of fluorochrome dyes make it possible to explain the contradicting presentations of the vascular system of the growth plate in the literature. The vascular system was casted with methacrylates which can be presented in the scanning electron microscope 3-dimensionally together with the trabeculae as a result of their resistance in the electron beam.

The 3-dimensional presentation in the electron microscope allows a clear distinction between the various vascular sections in the arterial flow system. In the microcorrosion casts the vessels of the epiphyseal side of the growth plate can …


Sexual Differentiation Of The Rat Hypothalamus: An Evaluation Of Sexual Behavior And Hypothalamic Morphology Following Neonatal Manipulation, Michael C. Stamper Aug 1984

Sexual Differentiation Of The Rat Hypothalamus: An Evaluation Of Sexual Behavior And Hypothalamic Morphology Following Neonatal Manipulation, Michael C. Stamper

Morehead State Theses and Dissertations

A thesis presented to the faculty of the School of Sciences and Mathematics at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by Michael C. Stamper on August 24, 1984.


Effects Of Dehydration On Hemoglobin Oxygen Affinity And Blood Cell Volume In Two Anurans, Andrew Christopher Zygmunt Aug 1984

Effects Of Dehydration On Hemoglobin Oxygen Affinity And Blood Cell Volume In Two Anurans, Andrew Christopher Zygmunt

Dissertations and Theses

Two aspects of possible adaptation in cardiovascular performance caused by increased plasma electrolytes were examined. Cells in anisotonic plasma may either act as osmometers or volume regulate. Blood flow rate is dependent upon cell viscosity, which in turn is a consequence of cell volume and membrane deform-ability. Cell volume changes which increase membrane deform-ability will thus potentially extend the limits of dehydration tolerance. It was found in R. catesbeiana and B. marinus that red blood cell is maintain constant volume during dehydration. Cells in vitro initially lose water, but then sodium, potassium and water move into the cell. Cell viscosity …


In Vitro Glucose Utilization In Ob/Ob Mouse Erythocytes & Adipose Tissue, Peggy Fudge Aug 1984

In Vitro Glucose Utilization In Ob/Ob Mouse Erythocytes & Adipose Tissue, Peggy Fudge

Masters Theses & Specialist Projects

An in vitro study of ob/ob mouse and control mouse erythrocytes and adipose tissue showed a difference in the rate of glucose utilization as determined by the production of 3H20. In both ob/ob and control erythrocytes, glucose utilization increased as glucose concentration of the medium was increased, although the ob/ob rate was consistently lower than the control. The similar trend except for the adipose tissues showed a ob/ob adipose tissue at 200 mg/d1 glucose concentration which exhibited a rate less than the rate at 100 mg/d1.

The decreased glucose utilization by adipose tissue in the absence of …


Chemical Leaf Repellency To An Attine Ant: Seasonal Distribution Among Potential Host Plant Species, Jerome J. Howard Aug 1984

Chemical Leaf Repellency To An Attine Ant: Seasonal Distribution Among Potential Host Plant Species, Jerome J. Howard

Biological Sciences Faculty Publications

The chemical repellency of leaves to the leaf-cutting, fungus-growing ant Atta cephalotes was surveyed for 42 plant species randomly selected from the dry forest of Santa Rosa National Park, Guanacaste, Costa Rica. The sample represents about one-sixth of the potential host plant species available to the ants in the secondary, semideciduous forest at Santa Rosa. Repellencies of leaf extracts were measured by bioassay. A laboratory colony of A. cephalotes collected from Santa Rosa was used. Three-quarters of the species exhibited significantly repellent nonpolar (lipid-soluble) extractables (e.g., terpenoids, steroids, and waxes), and half of the species exhibited repellent polar extractables (e.g., …


Studies On The Phytoplankton Of Littoral Waters Of The Arabian Gulf As Impacted By Oil Spills, Hamdan S. Al-Ghamdi Aug 1984

Studies On The Phytoplankton Of Littoral Waters Of The Arabian Gulf As Impacted By Oil Spills, Hamdan S. Al-Ghamdi

Masters Theses

A study of the effect of oil pollution on two intertidal areas of the Saudi Arabian Gulf coast was undertaken. One area was severely impacted by oil; the other was relatively clean. The organisms studied also indicated the effects of pollution were diatoms and blue-green algae.

Members of the diatom genus Amphora were more numerous in the clean water area than in the polluted section, confirming their preference for relatively clean habitats. Members of the diatom genus Asterionella, a more resistant group, were much more abundant in the polluted area.

Blue-green algae which also tolerate pollution were also more abundant …


An Evaluation Of Naturally Occurring Populations Of Magnolia Tripetala L. In Indiana, Kemuel S. Badger Aug 1984

An Evaluation Of Naturally Occurring Populations Of Magnolia Tripetala L. In Indiana, Kemuel S. Badger

All-Inclusive List of Electronic Theses and Dissertations

Magnolia tripetala L. occurs in Indiana as a disjunct from the Appalachian mountains populations. Currently, the known distribution of ~· tripetala in Indiana is confined to seven sites in Crawford County. The current status of ~· tripetala and the surrounding plant community was evaluated to aid in the future study, protection and management of this species, which is endangered in Indiana. Systematic random sampling of the tree stratum was done with belt transects. The sapling and seeding strata were sampled with subplots, placed along the belt transects. Permanent plots were established to enable future monitoring of what is currently prime …


Effects Of Intraperitoneal And Intracerebral Injections Of Triiodothyronine On Temperature Selection In Fish, Dennis A. Grahn May 1984

Effects Of Intraperitoneal And Intracerebral Injections Of Triiodothyronine On Temperature Selection In Fish, Dennis A. Grahn

Dissertations and Theses

Goldfish (Carassius auratus) of 15-28g were maintained at 23 C and subsequently were intraperitoneally injected with saline (controls) and varying doses of Triiodothyronine (T3). Following the injection, the fish were placed in a thermal gradient and temperature selection and activity monitored for 30 min. There was no- significant difference between the responses of the experimental fish to the 2 different doses of T3. However, there was a significant difference in response between the experimental and control groups (P < 0.001). The decreased temperature selection occurred early in the test runs, while the increased activity began later. Larger goldfish (175-205g) received 0.5 μl intracerebral injections of 1.5-3.0 ng T3 in the anterior brainstem via an indwelling cannula injection system. These fish responded to the injections by …


Ua66/6/2 Alumni Newsletter, Wku Biology May 1984

Ua66/6/2 Alumni Newsletter, Wku Biology

WKU Administration Documents

Newsletter created by and about the WKU Biology department highlighting students, faculty and alumni activities.


Effects Of Adrenalectomy On Hemoconcentration And Blood Ph, Urea And Electrolytes In The Mongolian Gerbil (Meriones Unguiculatus), Magally Aellos De Cova May 1984

Effects Of Adrenalectomy On Hemoconcentration And Blood Ph, Urea And Electrolytes In The Mongolian Gerbil (Meriones Unguiculatus), Magally Aellos De Cova

Master's Theses

The effects of adrenalectomy on some blood profiles of the Mongolian gerbil, Meriones unguiculatus, were studied in order to clarify the possible causes of its short survival after adrenal ablation. Measurements of hematocrit, pH, urea and electrolytes were made 18, 24 and 30 hours after surgery. Results show the expected alterations: hemoconcentration, metabolic acidosis, high values of urea and disturbances in electrolytes. While hyponatremia was significant only after 24 hours, important hypochloremia was not present at any time. Hyperkalemia was the most significant alteration observed. It occurred as early as 18 hours after surgery, suggesting that it may be an …


Seasonal And Spatial Heterogeneity In The Limnetic Zooplankton Community Of Lake Mead, Gene Robert Wilde May 1984

Seasonal And Spatial Heterogeneity In The Limnetic Zooplankton Community Of Lake Mead, Gene Robert Wilde

Publications (WR)

Zooplankton samples collected from throughout Lake Mead, in 1981-1982, demonstrate the presence of a statistically significant seasonal and spatial heterogeneity in zooplankton densities. Seasonally, the major zooplankton groups were most abundant in the spring and fall, coincident with maxima in chlorophyll-a concentrations. Successions among the various rotifers, cladocerans and copepods present in the reservoir were influenced by food availability, diapause, predation by planktivorous fish and, possibly, water temperatures. Spatial heterogeneity in zooplankton densities was unrelated to water temperature, pH, conductivity and dissolved oxygen concentrations, but was related to the abundance of phytoplankton (chlorophyll-a concentrations) and fish. Statistical analyses indicate that …


Effects Of Folic Acid Or Zinc Malnutrition On Rotaviral Infection In A Murine Model, John Douglas Morrey May 1984

Effects Of Folic Acid Or Zinc Malnutrition On Rotaviral Infection In A Murine Model, John Douglas Morrey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The influences of dietary deficiencies of folic acid or zinc on rotaviral disease infant mice were studied. Preliminary studies indicated that bovine and simian rotaviruses, but not porcine rotavirus, caused diarrhea in infant mice. Bovine and porcine rotaviruses were not, however, sufficiently infectious to replace murine rotavirus in studies utilizing the murine model. It was also determined that murine rotavirus purified by a cesium chloride gradient was highly infectious and useful for subsequent studies on nutritional influences of rotaviral disease. In dietary studies, female Swiss Webster mice were fed diets containing deficient, moderately deficient, or adequate levels of folic acid …


Vocal Behavior And Interactions Among Parents And Offspring In The American Dipper, Mary Kathleen Fite May 1984

Vocal Behavior And Interactions Among Parents And Offspring In The American Dipper, Mary Kathleen Fite

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The American Dipper (Cinclus mexicanus), an inhabitant of rapidly flowing mountain streams, is an aquatic passerine whose vocalizations have previously been undescribed. This study examines the spectrographic characteristics and contexts of calls and song in a color-banded population of Dippers. Calls of adults are the Jih, Weep and Grawk calls; calls of nestlings and fledglings are the Chip and Beg calls. Adult Dippers have a limited number of call types which occupy a middle range of frequencies (3 to 6kHz) and have structural characteristics which enhance detection of vocal signals. Gradation is present between call types. Possible explanations …


Isolation Of A Collagenase Cdna Clone And Measurement Of Changing Collagenase Mrna Levels During Induction In Rabbit Synovial Fibroblasts., Robert H. Gross, Lynn A. Sheldon, Colin F. Fletcher, Constance E. Brinckerhoff Apr 1984

Isolation Of A Collagenase Cdna Clone And Measurement Of Changing Collagenase Mrna Levels During Induction In Rabbit Synovial Fibroblasts., Robert H. Gross, Lynn A. Sheldon, Colin F. Fletcher, Constance E. Brinckerhoff

Dartmouth Scholarship

To facilitate our studies on the mechanisms controlling collagenase production at a molecular level in rabbit synovial fibroblasts, we have constructed a cDNA library using mRNAs isolated from cells induced with crystals of monosodium urate monohydrate. We have screened this library with cDNA probes made from induced and control mRNA populations. From among 30 clones that hybridized preferentially to the induced-cell probe, 4 contained collagenase sequences. The largest, a clone of 650 base pairs, was identified by its ability to hybrid select a mRNA that could be translated in a cell-free system into a product that was precipitable with monospecific …


Factors Affecting Nest Site Location In Gila Woodpeckers, Jerome J. Korol, Richard L. Hutto Feb 1984

Factors Affecting Nest Site Location In Gila Woodpeckers, Jerome J. Korol, Richard L. Hutto

Biological Sciences Faculty Publications

We investigated the locations of Gila Woodpecker (Melanerpes uropygialis) nest sites in Organ Pipe Cactus National Monument, Arizona. A significantly greater proportion of saguaro cacti in arroyos had woodpecker holes than did those on hillsides, ridgetops or desert flats. Saguaros used for nest-hole excavation were taller and more likely to have branches than randomly chosen saguaros. Both active and inactive nest holes were nonrandomly oriented, with the mean vectors of orientation being in northwesterly directions. Variation in nest-hole orientation probably is not due to seasonal differences in excavations because the orientation of spring active (late March) nest holes was not …


Ecological And Evolutionary Considerations Of Large Scale Mosquito Control Programs, Harrison B. Tordoff Jan 1984

Ecological And Evolutionary Considerations Of Large Scale Mosquito Control Programs, Harrison B. Tordoff

Journal of the Minnesota Academy of Science

No abstract provided.


Toward A Concise Definition And Perspective For Biology, Arthur V. Brown, Kristine Basinger Brown Jan 1984

Toward A Concise Definition And Perspective For Biology, Arthur V. Brown, Kristine Basinger Brown

Journal of the Arkansas Academy of Science

The content of introductory biology courses at the high school and college levels are currently being re-examined. Many biological educators favor revision of the high school biology courses to a format that directly addresses current social issues to "promote good citizenship". We believe it would be more meaningful to teach the fundamental principles of biology, the study of living systems. Properly defining biology, by defining a living system, should help identify important topics to include in a basic biology course. Emphasis should be placed on subjects which would contribute most to the development of a basic understanding of how all …


Superior Developmental Stability Of Heterozygotes At Enzyme Loci In Salmonid Fishes, Robb F. Leary, Fred W. Allendorf, Kathy L. Knudsen Jan 1984

Superior Developmental Stability Of Heterozygotes At Enzyme Loci In Salmonid Fishes, Robb F. Leary, Fred W. Allendorf, Kathy L. Knudsen

Biological Sciences Faculty Publications

No abstract provided.


The Pan American Shorebird Program: A Progress Report, J. P. Myers, Gonzalo Castro, Brian Harrington, Marshall Howe, John L. Maron, Enrique Ortiz, Michel Sallaberry A., C. T. Schick, Elier Tablio Jan 1984

The Pan American Shorebird Program: A Progress Report, J. P. Myers, Gonzalo Castro, Brian Harrington, Marshall Howe, John L. Maron, Enrique Ortiz, Michel Sallaberry A., C. T. Schick, Elier Tablio

Biological Sciences Faculty Publications

No abstract provided.


Herbivory Effects On Thalassia Testudinum Leaf Growth And Nitrogen Content, J. C. Zieman, R. L. Iverson, John C. Ogden Jan 1984

Herbivory Effects On Thalassia Testudinum Leaf Growth And Nitrogen Content, J. C. Zieman, R. L. Iverson, John C. Ogden

Integrative Biology Faculty and Staff Publications

The pattern of turtle grazing on Thalassia testudinum in St. Croix seagrass beds begins with the establishment of a grazing plot by initial removal of leaf blades, followed by repeated grazing of several centimeter-long leaf blades within a maintained grazing area. Plants within the grazed area exhibit increased specific growth rate as a consequence of increased light flux to unepiphytized leaf bases. Leaf width is reduced in the grazed area as a consequence of grazing stress. The leaf bases contain a higher proportion of nitrogen and a lower lignin content than the leaf tips, in addition to lacking epiphytes. Our …


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 …


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 …