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Studies On Encephalomyocarditis Virus-Induced Diabetes In Mice, John Henry Huffman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The D-variant of encephalomyocarditis (EMC-D) virus was given to SJL/J mice by the artificial, intraperitoneal (ip) route of infection, or by the natural routes of infection per os (po) or intranasal (i.n.), in comparable concentrations. The po route of infection was found to be ineffective. Mice given virus by either the ip or i.n. routes of infection became diabetic. Mice were more resistant to the infectious and diabetogenic properties of the virus when given by the i.n. than when given by the ip route. Glycosuria in mice given virus i.n. usually lagged one day behind that in mice given virus …

Patterns Of Singing By House Wrens With Respect To The Breeding Cycle, Michael H. Tove

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I recorded the songs and studied the reproductive behavior of a population of marked House Wrens (Troglodytes aedon) to identify patterns of singing and correlate them with behavioral contexts and stages of the breeding cycle. I found that House Wren singing could be organized into three hierarchical regimes: routine patterns of daily singing, context-specific patterns of singing and long-term fluctuations in singing rate throughout the breeding cycle. During routine daily singing, predictable structural changes occurred. Songs were clustered in discrete groups called bouts. The songs within a bout were more similar in structure than songs from different bouts. …

Characterization Of Esterases And Glutathione S-Transferases In A Solitary Bee, Megachile Rotundata (Fab.): Variability, Developmental Multiplicity, Substrate Specificity, And Inhibition, Donald R. Frohlich

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The esterases and glutathione S-transferases of a solitary bee, Megachile rotundata (Fab.) (Hymenoptera: Megachilidae), the alfalfa leafcutting bee, were characterized by electrophoresis, substrate specificity, and inhibition studies. Comparisons were made between ages, sexes, and life stages for several classes of substrates and their isomers: aromatic, aliphatic, and thio-esters. Two esterases were found to be allozymes and variable between individuals and sexes. Adults typically possess an esterase that hydrolyzes fluorescent substrates, an organophosphate insensitive esterase, and a series of type 'B' esterases that are very sensitive to organophosphate inhibition. Electrophoretic patterns are different between adults and immatures and are probably …

Surface And Sub-Surface Composition And Properties Of Ion-Bombarded Lithium Alloys, A. R. Krauss, D. M. Gruen, N. Q. Lam, A. B. Dewald, M. G. Valentine, A. Sagara, K. Kamada

Scanning Microscopy

Lithium-bearing alloys such as Si-Li, Al-Li and Cu-Li are of importance in a variety of technological applications, many of them depending on the fact that the surface composition of these alloys differs significantly from that of the bulk, both at thermal equilibrium and under ion bombardment. During ion sputtering, these materials exhibit a variety of phenomena which affect the surface composition and concentration depth profile in a complex manner. We present here experimental measurements of the surface and near-surface composition profiles of sputtered Cu-Li and Al-Li alloys. The experimental results are interpreted in terms of surface loss and radiation-induced segregation …

Multiphoton Ionization Followed By Time-Of-Flight Mass Spectroscopy Of Sputtered Neutrals, M. J. Pellin, C. E. Young, D. M. Gruen

Scanning Microscopy

Multiphoton ionization (MPI) by pulsed, tunable lasers provides a sensitive means for detection of neutral atoms, resulting from the high probability achievable in both the ionization and subsequent detection steps. Substantial selectivity is achieved by excitation between energy levels of the atom of interest. This resonant MPI technique can access all atomic states including ground and metastable levels.

The high efficiency of MPI technique permits detailed sputtering data to be obtained with minimal target damage. The goal is to obtain velocity and angular distributions for each energy level of every sputtered species. In practice, two types of experimental configurations have …

A New Method For Finishing Minicavities, A. Lussi, M Gygax, P. Hotz, D. Lüthi

Scanning Microscopy

Minicavities were prepared in 26 caries-free teeth. Cavity preparation and the finishing of the occlusal area and the gingival floor was done with diamond burs (diameter 1 mm, grain sizes 90 μm and 15 μm, respectively). For the finishing of the axial box margin and the proximo-cervicaI curved border, a new set was developed: It is composed of an EVA-system with the total amplitude reduced to 0.34 mm, and a highly flexible file (Cavishape, grain 15 μm). The shape of this file had to be modified in order to follow the proximo-cervical curvature. The efficiency of the new device was …

Proton Microprobe And Particle Induced X-Ray Emission (Pixe) Analysis For Studies Of Pathological Brain Tissue, K. G. Malmqvist, A. Brun, K. Inamura, E. Martins, L. G. Salford, B. K. Siesjö, U. A. S. Tapper, K. Themner

Scanning Microscopy

Particle Indiced X-ray Emission and proton microprobe analyses have been applied for the investigation of regional elemental distributions in connection with various pathological states in the brain. Malignant brain tumours and adjacent histologically intact tissue removed during surgery were analysed with PIXE. Systematic elemental variations, e.g., for calcium and selenium, were observed in the tumour front. The proton microprobe was applied to study the Ca and K concentrations in various cell strata in hippocampus following transient ischaemia in rat brain. Significant increases in the Ca level occurred in selectively vulnerable cells within 48 h after the ischaemia.

The Growth Of Calcium And Strontium Sulfates On Barium Sulfate Surfaces, L. Perez, G. H. Nancollas

Scanning Microscopy

The crystallization of calcium sulfate dihydrate (gypsum) and strontium sulfate (celestite) induced by the presence of barium sulfate (barite) surfaces has been studied using a Constant Composition kinetic method. In contrast to calcium sulfate, strontium sulfate appears to grow epitaxially on barium sulfate surfaces. However, barium sulfate induces calcium sulfate dihydrate precipitation from meta stable supersaturated solutions of the salt. Following nucleation, the rate of growth of strontium sulfate was found to be a second order with respect to supersaturation indicating a surface dislocation growth mechanism. The observed epitaxial growth is in agreement with calculations based on crystal lattice mismatch.

Zinc Deficiency: Specific Scalp Hair Defects Seen By Scanning Electron Microscopy May Provide A Valuable New Test, D. W. Gregory, L. Stankler

Scanning Microscopy

Zinc deficiency in man results in multisystem disease. It may be acquired or hereditary; the latter can be fatal if left untreated. Premature babies are particularly susceptible to zinc deficiency. Unfortunately no simple, reliable test for zinc status exists at present.

Short, newly-emerging scalp hair samples from 3 classical cases of zinc deficiency all showed the same characteristic abnormalities when examined by scanning electron microscopy, i.e. straight, blunt tips bearing scales, unusually thick cuticular scales with jagged free-edges, and very fine longitudinal corrugations in individual scales. These abnormal features occurring together appear to be specific for zinc deficiency; they also …

Characteristics Of Binding Of Interleukin-1 To Yt.Nci Cells, Susan Catherine Speziale

Masters Theses

Interleukin-1 (IL-1) demonstrated a concentration dependent, specific binding to the human, large granular lymphocyte cell line, YT.NCI with a dissociation constant of 0.2 nM. There were approximately 500 IL-1 receptors/cell.

IL-1 binding to YT.NCI cells could be inhibited by unlabeled-IL-1 and the plant lectins, WGA and Con A. Lectin inhibition of IL-1 binding could be completely abrogated by exposing lectins to specific simple sugars prior to the addition of ligand.

Tunicamycin, an inhibitor of glycosylation, decreased IL-l binding to YT cells in a reversible, time- and concentration-dependent manner.

These observations suggest that glycosylation of cell surface proteins may be important …

Effects Of Ethanol And Caffeine Administered Maternally On Neonatal Adrenocortical Function, Rhonda L. Mullins Rohlfing

Biological Sciences Theses & Dissertations

Two investigations were conducted to determine the effects of maternally administered ethanol and caffeine on neonatal adrenocortical function. In the ethanol study, pregnant female rats were fed a liquid diet in which 35% of the sucrose calories were removed and replaced with ethanol. Dams in the caffeine study were injected with 25 mg/kg/day caffeine in saline solution. Within 24 hours of parturition, neonatal rats in both studies were sacrificed. The adrenal glands were incubated in vitro for one hour and media were analyzed for corticosterone content. Significant adrenal weight differences were found in both studies. The ethanol group pups were …

Transformation Of Tetrahymena Thermophila With Hypermethylated Rrna Genes, Kathleen M. Karrer, Meng-Chao Yao

Biological Sciences Faculty Research and Publications

The extrachromosomal rRNA genes (rDNA) of Tetrahymena thermophila contain 0.4% N6-methyladenine. C3 strain rDNA was isolated, hypermethylated in vitro, and microinjected into B strain host cells. Clonal cell lines were established, and transformants were selected on the basis of resistance to paromomycin, conferred by the injected rDNA. The effects of methylation by three enzymes which methylate the sequence 5'-NAT-3', the dam, EcoRI, and ClaI methylases, were tested. Hypermethylation of the injected rDNA had no effect on transformation efficiency relative to mock-methylated controls. The injected C3 strain rDNA efficiently replaced host rDNA as the major constituent of the population of rDNA …

Scanning Electron Microscopy Of The Spermatheca Of Plethodon Larselli (Amphibia: Plethodontidae): Changes In The Surface Morphology Of The Spermathecal Tubule Prior To Ovulation, Christine M. Davitt, John H. Larsen Jr.

Scanning Microscopy

Spermathecae from eight mature female Larch Mountain salamanders (Plethodon larselli) were used to study cellular changes accompanying the administration of ovulation-inducing pregnant mare serum gonadotropin (PMSG). Animals injected daily with 25 IU of PMSG were sacrificed on day 2 or day 4. Ultrastructural alterations of the spermathecal tubules include an increase in the synthesis and release of product into the lumen and hypertrophy of two epithelial cell types by day 4. One cell type exhibits apocrine blebs and is covered with microvilli; the other contains large spherical vesicles and has only a few, short microvilli on its surface. These changes …

Developmental And Radiobiologic Characteristics Of Canine Multinucleated, Osteoclast-Like Cells Generated In Vitro From Canine Bone Marrow, T. M. Seed, L. V. Kaspar, F. Domann, G. K. Niiro, D. A. Lebuis

Scanning Microscopy

We report here our initial observations on the growth and morphology, and developmental radiosensitivity of giant, multinucleated, osteoclast-like cells (MN-OS} generated through in vitro cultivation of hematopoietic progenitor-enriched canine bone marrow samples. Maximum cell densities of 5.5 x 10³ to 6.5 x 10³ MN-OS per cm² of growth area were achieved following 10 to 14 days of culture at 37°C. Acute gamma irradiation of the initial marrow inocula resulted in significant, dose-dependent perturbations of MN-OS formation, growth, and development. Attempts to estimate radiosensitivity of MN-OS progenitors from canine marrow yielded a range of D_O values from …

Sem Of Canine Chromosomes: Normal Structure And The Effects Of Whole-Body Irradiation, G. K. Niiro, T. M. Seed

Scanning Microscopy

Canine chromosomes are not only numerous (38 autosomal pairs), but they are small (compared to human chromosomes) and morphologically similar as well. Analysis of the canine karyotype by light microscopy (LM) of banded chromosomes is, thus, difficult, and the literature on the canine karyotype is scanty. In this study, we describe examination of chromosomes from normal and chronically irradiated dogs with the scanning elect ran microscope (SEM). Metaphase chromosomes from bone marrow aspirates were Giemsa-banded with either 0.025% trypsin alone or 0.1% trypsin preceded by 10% H2O2 and prepared for SEM. Examination of chromosomes from normal dogs revealed cylindrical chromosome …

Silver As A Removable Conductive Coating For Scanning Electron Microscopy, A. A. Mills

Scanning Microscopy

A thin film of silver, applied by sputtering or vacuum evaporation, provides an excellent conformal conductive coating for scanning electron microscopy of insulating specimens. When no longer required it is easily removed with Farmer's reducer a dilute aqueous solution of potassium ferricyanide and sodium thiosulphate. No damage was apparent to fine structure in the calcite matrix of ostracode shells, or to other biological tissues. No problems have been encountered with grain in the silver film at magnifications up to 15,000 X, or in the storage of coated specimens in a desiccator for periods exceeding 6 months.

Enamel Structure In Primates: A Review Of Scanning Electron Microscope Studies, L. B. Martin, A. Boyde, F. E. Grine

Scanning Microscopy

Comparative studies of dental enamel microstructure have involved three main areas of enquiry, with structural features having been investigated in relation to developmental mechanisms, function and/or phylogeny. The phylogenetic, or taxonomic aspect has been emphasized in the majority of studies involving the Order Primates, where efforts have focused upon attempts to recognise structural differences among various hierarchical groups.

Studies of primate enamel microstructure by SEM are reviewed here, with emphasis on what has been learned concerning the most suitable preparative techniques that can be employed, and with particular emphasis to the relevance of enamel microstructure in taxonomic analyses of living …

The Capabilities Of The Microprobe Kontron Image Analysis System: Application To Mineral Beneficiation, W. Petruk

Scanning Microscopy

Image analysis is a technique for determining quantities, grain size distributions, grain orientations, intergrowths, associations, liberations and degrees of alteration of minerals or phases in naturally occurring and processed materials. It is performed by analysing images of polished or thin sections of the material under study. To obtain accurate results the images must be faithful reproductions of the material, and each mineral or phase displayed in the images must be distinct enough to be automatically discriminated and identified without operator interaction. An image analysis system that meets these requirements was developed in the Process Mineralogy Section at CANMET by interfacing …

The Effects Of Polepiece Saturation On The Electron Optical Properties Of Asymmetric Condenser - Objective Lenses, Wenxiong Chen

Scanning Microscopy

The electron optical properties of an asymmetric magnetic condenser-objective lens are determined not only by its geometric structure and shape parameters, but also by the degree of saturation of its polepieces. A systematic investigation has been carried out for a series of asymmetric magnetic condenser-objective lenses. Results show that, owing to its small bore, the lower polepiece of such an asymmetric condenser-objective lens has considerable effects on the electron optical properties. When this polepiece is appropriately highly saturated, an asymmetric condenser-objective lens possesses low spherical aberration and chromatic aberration coefficients. On the other hand, the large bore of the upper …

Makaira Sp., Cf. M. Nigricans Lacepede, 1802 (Teleostei: Perciformes: Istiophoridae) From The Eastover Formation, Late Miocene, Virginia, And A Reexamination Of Istiophorus Calvertensis Berry, 1917, Harry L. Fierstine

Biological Sciences

An incomplete, disarticulated skull (USNM 375733) is described and referred to Makaira sp., d. M. nigricalls, and a rostrum, tIstiophonls call'ertensis Berry. 1917 (USNM 9344. holotype). is re-identified as IstiopllOrus sp., cf. I. platypterus. Both specimens are from the Eastover Formation (early late Miocene, Virginia) and are the oldest records in. deposits bordering the western North Atlantic Ocean. Istioplwrus sp.. cf. I. p/atvpterus (= tlstiophorus ca/vertensls ) IS the oldest record of the specIes. Based on ecological requirements of Recent species. the prescnce of Istiophorus sp., cL I. p/arypterus and Makaira sp., cf. M. nigricans in the Eastover Formation indicates …

Dna Probe Method For The Detection Of Specific Microorganisms In The Soil Bacterial Community, William Holben, Janet K. Jansson, Barry K. Chelm, James M. Tiedje

Biological Sciences Faculty Publications

We developed a protocol which yields purified bacterial DNA from the soil bacterial community. The bacteria were first dispersed and separated from soil particles in the presence of polyvinylpolypyrrolidone, which removes humic acid contaminants by adsorption to this insoluble polymer. The soil bacteria were then collected by centrifugation and lysed by using a comprehensive protocol designed to maximize disruption of the various types of bacteria present. Total bacterial DNA was purified from the cell lysate and remaining soil contaminants by using equilibrium density gradients. The isolated DNA was essentially pure as determined by UV spectral analysis, was at least 48 …

Microscopic Effects Of Predator Digestion On The Surfaces Of Bones And Teeth, John M. Rensberger, Hartmut B. Krentz

Scanning Microscopy

Concentrations of small fossil mammals are frequently encountered in Cenozoic deposits, but the causes for such accumulations have seldom been determined. In many cases the tooth, jaw, and limb fragments appear to be well-preserved under light microscopy, and it is difficult to differentiate damage due to predator digestion from breakage and abrasion due to physical agents. In order to find more specific evidence of predator digestion, we used a scanning electron microscope (SEM) to examine the surface microstructure of bones and teeth consumed by Bubo virginianus (great horned owl) and Canis latrans (coyote), which prey upon similar species. Effects …

Identification Of Defined Sequences In Domain V Of E.Coli 23s Rrna In The 50s Subunit Accessible For Hybridization With Complementary Oligodeoxyribonucleotides, Richard T. Marconi, Walter E. Hill

Biological Sciences Faculty Publications

The accessibility of specific sequences in domain V of E. coli 23s rRNA in the 50S subunit to complementary oligodeoxyribonucleotides (cDNA) has been investigated. The apparent percentage of subunits engaged in complex formation was determined by incubation of radiolabeled cDNA probe with 50S subunits, followed by nitrocellulose membrane filtration of the reaction mixtures and measurement of the bound radiolabeled cDNA probes by liquid scintillation counting of the filters. The site(s) of hybridization were determined by digestion of the RNA in the RNA/DNA heteroduplex by RNase H. The results of this study indicated that single-stranded sequences, 2058-2062, 2448-2454, 2467-2483, and 2497-2505 …

Metal Ion And Cluster Beams For Microelectronic Research And Development: A Review, G. Ben Assayag, P. Sudraud

Scanning Microscopy

Applications of focused ion and cluster beams emitted by liquid metal ion sources are particularly attractive in microelectronic engineering. We overview this area of research and development adding recent results concerning repair, tuning and characterization obtained either by focusing ions or droplets on a microcircuit controlled by in-situ SEM observation of the process.

Febrile Response And Activity In The Crayfish, Pacifasticus Leniusculus Trowbridgii, Kenneth A. Fletcher

Dissertations and Theses

Poikilothermic and endothermic animals demonstrate febrile response to infection with bacteria or to injection with endogenous pyrogen extract of Prostaglandin E₁. Febrile response is measured in endotherms as a relative change in metabolically achieved body temperature and in poikilotherms as an increase in selected temperatures relative to previously established preferred temperatures. Final preferendum change with environmental factors or associated physiological states.

Crayfish Pacifasticus leniusculus trowbridgii were injected with 0.2 ml suspension of alcohol-killed gram-negative Aeromonas hydrophila bacteria in 0.9% saline. Injections were into the coxopodite of the cheliped. The crayfish were monitored in an aquatic thermal gradient by …

Leafcutting And Diet Selection: Relative Influence Of Leaf Chemistry And Physical Features, Jerome J. Howard

Biological Sciences Faculty Publications

The effects of leaf toughness, trichome characteristics, nutrient and water availability, and secondary chemistry on diet selection by the leafcutting ant Atta cephalotes were determined using individuals of 49 woody plant species from a tropical deciduous forest in Costa Rica. The palatability of plants was measured by presenting whole leaves to leafcutting ant foragers on trails and counting the number of pieces cut from leaves. The effectiveness of physical barriers to leaf cutting was evaluated by measuring the speed with which ants were able to cut leaves of varying toughness, trichome densities, and trichome lengths. Plant secondary chemistry was highly …

The Itasca State Park Algal Culture Collection At Loras College, David B. Czarnecki, M. Jon Ross

Journal of the Minnesota Academy of Science

A list of over 125 algal cultures originating from Lake Itasca State Park is presented. These cultures, permanently housed at Loras College, Dubuque, Ia., include 115 taxa representing 68 genera from six algal Divisions. Approximately one-third of the taxa are desmids.

The Diatom Flora Of The Red Lake Peatland, Minnesota, Thomas P. Pienkowski, Daniel E. Wujek

Journal of the Minnesota Academy of Science

Diatoms collected from three transects in the Red Lake Peatland occur in characteristic assemblages. One hundred two taxa were observed from 26 sample sites, with Eunotia exigua and Pinnularia rupestris the most dominant species. Clustering indicated three peatland types were present: rich fen, transitional and poor fen, and bog.

Genetic Distance And Hybridization Of Black Ducks And Mallards: A Morph Of A Different Color?, G. R. Hepp, James M. Novak, K. T. Scribner, P. W. Stangel

Faculty Research & Creative Activity

No abstract provided.

The Genera Of Bambusoideae (Gramineae) In The Southeastern United States, Gordon Tucker

Faculty Research & Creative Activity

No abstract provided.