Biology Commons^™

Foraging Ecology Of The Mangrove Salt Marsh Snake, Nerodia Clarkii Compressicauda: Effects Of Vegetational Density [Abstract], Stephen J. Mullin, Henry R. Mushinsky

Faculty Publications

No abstract provided.

Association Of Mouse Fibrinogen-Like Protein With Murine Hepatitis Virus-Induced Prothrombinase Activity, Rebecca D. Parr, Laisum Fung, Jeffrey Reneker, Nancy Myers-Mason, Julian L. Leibowitz, Gary Levy

Faculty Publications

Previously, we demonstrated induction of a unique macrophage prothrombinase during infection of BALB/cJ mice by mouse hepatitis virus strain 3 (MHV-3). By immunologic screening, a clone representing this prothrombinase was isolated from a cDNA library and sequenced. The sequence identified this clone as representing part of a gene, musfiblp, that encodes a fibrinogen-like protein. Six additional clones were isolated, and one clone, p11-3-1, encompassed the entire coding region of musfiblp. Murine macrophages did not constitutively express musfiblp but, when infected with MHV-3, synthesized musfiblp-specific mRNA. musfiblp mRNA induction was earlier and significantly greater in BALB/cJ than A/J …

Molecular Mimicry Between Fc Receptor And S Peplomer Protein Of Mouse Hepatitis Virus, Bovine Corona Virus, And Transmissible Gastroenteritis Virus [Abstract], Emilia L. Oleszak, Jacek Kuzmak, Brenda Hogue, Rebecca D. Parr, Ellen W. Collisson, L. Scott Rodkey, Julian L. Leibowitz

Faculty Publications

No abstract provided.

Statistical Analyses Of Environmental Predictors For Phytoplankton Photosynthetic Parameters And Productivity In An Antarctic Time Series Database, Mark A. Moline, Barbara B. Prezelin, Oscar Schofield

Biological Sciences

No abstract provided.

Palmer Lter: Photoacclimation In A Coastal Phytoplankton Bloom, Oscar Schofield, Mark A. Moline, Barbara B. Prezelin

Biological Sciences

No abstract provided.

Induction Of Larval Settlement By Kcl In Three Species Of Bugula (Bryozoa), Dean E. Wendt, Robert M. Woollacott

Biological Sciences

Elevation of the K⁺ concentration in seawater (added as KCl) induces larval settlement and metamorphosis in Bugula simplex, B. stolonifera, and B. turrita. All three of these bryozoan species have similar bell-shaped dose-response curves: 5 mM excess K⁺ is sufficient to increase settlement and metamorphosis significantly over seawater controls in all the species and optimal responses to excess K concentrations occur ations at 10-25 mM, 5-10 mM, and 10-15 mM for B. simplex, B. stolonifera, and B. turrita, respectively. Percent settlement in all three species is decreased at levels greater than 25 mniM excess …

Three-Dimensional Thermoluminescence Spectra And Their Application In The Study Of Some Sedimentary Quartz, J. R. Prescott, R. B. Scholefield, A. D. Franklin

Scanning Microscopy

The intensity of thermoluminescence emission is a function of both temperature and photon energy (or wavelength) and therefore lends itself to a three-dimensional (3-D) display, either in the form of an isometric plot or a contour diagram. The technique of 3-D thermoluminescence spectrometry is briefly reviewed and the advantages and applications are illustrated by reference to the spectral properties of samples of Australian sedimentary quartz drawn from the context of thermoluminescence dating. In this context, the temperature of emission, the photon energy and the ease with which the emission is bleachable by sunlight are of significance. It is suggested that, …

Geographic And Nongeographic Variation In The Genus Microtus (Mammalia: Rodentia) In West Virginia, Tina M. Savage

Theses, Dissertations and Capstones

Geographic and nongeographic variation was assessed on 12 cranial and 4 external characters in approximately 400 specimens of Microtus (M. ochrogaster, M. chrotorrhinus, M. pinetorum, M. pennsylvanicus) in West Virginia. Univariate and multivariate statistical analyses were used to examine age-related variation, sexual dimorphism, elevation and geographic variation and litter size for each species of Microtus in the state. Cranial characters were more beneficial than external in detecting variation. Examination of data for each species of Microtus studied demonstrated that values and trends in variation is a specific rather than a generic trait. Age-related variation was present in some, …

The Effects Of An Early Season Clipping On Several Grassland Species, Bradley J. Matuska

Honors Theses, 1963-2015

In one year, the Proposed 100-Acres Quarry Park, Stearns County, Minnesota, USA, will be undergoing development. One aspect of the development is the management (i.e. burning, seeding, clipping) of an old grassland within the park. I studied clipping as a management scheme and expected the species richness (number of species) to increase after clipping and the prostrate species to respond better than the erect species. I used the Daubenmire Canopy-Coverage Method to measure my results. The species richness showed no significant change in response to clipping mainly due to the timing of the clipping. However, individual species responded differently to …

Small Mammals Of Quarry Park Stearns County, Mn, David Winecoff

Honors Theses, 1963-2015

This wilderness quarry area is in the process of being converted for public use by Stearns Co., and is an ideal area for ecological surveys. I assessed the small mammal distributions in the variety of habitat types within the park, from June to August 1994. The habitats included: grasslands, Oak, Aspen, and Red Pine forests, wetlands, rock tailing piles, natural rock outcroppings, and water-filled quarries. I conducted this survey using Sherman Live traps, scat boards, and pit traps. The grassland consisted exclusively of Microtus pennsylvanicus, except for a single Sorex cinereus. Peromyscus leucopis dominated in the forests within …

Bones Of Puffinus Lherminieri Lesson (Aves: Procellaridae) And Two Other Vertebrates From Cueva Del Agua, Mona Isalnd, Puerto Rico (West Indies), Angel M. Nieves-Rivera, John M. Mylroie, Donald A. Mcfarlane

WM Keck Science Faculty Papers

From a dive in Cueva del Agua, Mona Island, Puerto Rico, twelve un-mineralized bones of Puffinus Lherminieri Lesson, one of Cyclura stejnegeri Stejneger, and one of Moormops blainvilii Leach were collected. The subfossil evidence confirms that P. Lherminieri was a common species on Mona Island. Cyclura stejnegeri and M. blainvilii probably became trapped and died in the pool chamber.

The Effects Of Nutrient Loading On Plant And Algae Population: A Comparison Study Of East Gemini Lake And Lower Stumpf Lake, Nick Leonard

Honors Theses, 1963-2015

Eutrophication of lakes has become an increasing problem for many bodies of water. By analyzing the nutrients available and the phytoplankton and macrophyte populations, evaluation and differentiation of East Gemini Lake and Stumpf Lake were made concerning their trophic state. This determination allowed for the further understanding of the effect the trophic state has on the flora of an aquatic system. It was determined that East Gemini Lake was eutrophic based on its available nutrients and phytoplankton populations. In contrast, Stumpf Lake was determined to be mesotrophic having lower available nutrients and less phytoplankton population density with fewer major phytoplnakton …

Effects Of Silvicultural Treatments In The Rocky Mountains, Sallie J. Hejl, Richard L. Hutto, Charles R. Preston, Deborah M. Finch

Biological Sciences Faculty Publications

We offer a description of current forest structure and basic information on bird distribution across forest habitats in the Rockies as background knowledge for understanding the effects of silviculture on birds in these habitats. We also offer a comparison between the effects of silviculture, and the effects of fire and fire suppression on forest birds in an attempt to give a holistic perspective on the health of forest birds' in the Rockies.

A Comparison Of Bird Detection Rates Derived From On-Road Versus Off-Road Point Counts In Northern Montana, Richard L. Hutto, Sallie J. Hejl, Jeffrey F. Kelly, Sandra M. Pletschet

Biological Sciences Faculty Publications

We conducted a series of 275 paired (on- and off-road) point counts within 4 distinct vegetation cover types in northwestern Montana. Roadside counts generated a bird list that was essentially the same as the list generated from off-road counts within the same vegetation cover type. Species that were restricted to either on- or off-road counts were rare, suggesting that restricted occurrences were a consequence of small sample sizes and not a product of habitat differences surrounding on-versus off-road points. Nevertheless, there were significant differences in the mean number of individuals detected between on- and off-road points for a number of …

Cathodoluminescent Properties Of Single Crystal Materials For Electron Microscopy, Rudolf Autrata, Petr Schauer

Scanning Microscopy

The results of measurements of cathodoluminescence efficiencies, decay characteristics and emission spectra of YAG:Ce, YAP:Ce, P47 (Y₂SiO₅:Ce) and CaF₂:Eu single crystals at excitation by electrons with an energy of 10 keV and a current density of the order of 10^-8 A cm^-2 are presented. Advantages and disadvantages of the individual single crystals intended for application in electron microscopes are dealt with. Attention is paid to the photomultiplier tube (PMT) matching, degradation and afterglow of the mentioned single crystals. For YAG:Ce, the effect of the activator concentration of crystals and the effect of …

Can Photo- And Cathodoluminescence Be Regarded As Complementary Techniques?, S. Myhajlenko, R. A. Puechner, J. L. Edwards, D. B. Davito

Scanning Microscopy

Photoluminescence (PL) usually provides macroscopic, high quality spectroscopic data. Cathodoluminescence (CL), on the other hand, offers the same information with microscopic imaging. However, replicating PL signatures in a CL system is not straightforward since matching experimental conditions, such as temperature and excitation density, is difficult. The matter is further exacerbated by inherent differences in the nature of excitation: electrons versus photons. Our work with high purity semiconductors suggests that CL is generally more sensitive to excitation "circumstance" than PL. For example, electrons can cause sample charging and contamination-related phenomena that dramatically affect CL. Changes in surface attributes (e.g., by chemical …

A New Model Of Low Temperature Photoluminescence In Amorphous Semiconductors, Mathieu Kemp, Marvin Silver

Scanning Microscopy

Recent low temperature a-Si:H photoluminescence experiments show the presence of two peaks in the lifetime distribution, and a dependence of the efficiency on generation rate. These results contradict every existing model of amorphous semiconductor photoluminescence. The reason for the discrepancy is that every model predicts diffusive motion of the photo-generated pairs. We show how the inclusion of coulomb interaction between photocarriers, spin selection effects, and Auger recombination gives back agreement of theory with experiment. This new picture of the phenomenon also explains the transient behavior of the luminescence intensity.

Advances In Research Of Defects In Quartz Based On Luminescence, A. Halperin

Scanning Microscopy

The first part of this paper reviews the observation of the unconventional thermoluminescence {TL(M), where M = Li or Na} peaks observed in the glow curve of Li-and Na-containing quartz, and describes the full solution of the puzzling effect of the TL(M) peaks which needed a two irradiation procedure for their formation. Of interest is the intermediate warming (IW) method, which consisted of two irradiations and warming of the sample to 150-300 K between the two irradiations. This was explained as follows: the first low temperature irradiation produces {AlO₄/M/h}⁺ centers, when the now loosely bound M ions …

Thermoluminescence Of Zircon, Philibert Iacconi

Scanning Microscopy

The thermoluminescence (TL) of synthetic zircons into which some impurities have been individually insert-ed is investigated. The results obtained show that, after X-irradiation at 77K, the synthetic zircons present three kinds of thermoluminescent emissions. The first is related to the OH^- ions, the second is typical of the SiO₄^4-groups, and the third is characteristic of RE³⁺ ions with RE = Dy, Tb, Gd, Eu, or Sm (RE = rare earth).

The OH^- emission is a large band at 285 nm which appears at 115 and 160K.

The SiO₄^4- TL emission consists of …

Cathodoluminescence Of Carbonates: New Applications In Geology And Archaeology, V. Barbin

Scanning Microscopy

Several new applications of cathodoluminescence (CL) have been developed during the last few years, including: combined CL imaging and/or spectroscopy and CL observations of carbonates previously considered to be non-luminescent or of minor interest. Basically, two previously unstudied types of carbonates were investigated: marbles, and recent shells. From numerous classical white marble samples, cathodomicrofacies were defined and described. A single cathodomicrofacies is generally characteristic of a given area. This finding permits identification of the source of white marbles and has been successfully applied to ancient marbles from different collections. Despite the well established idea that CL in biogenic carbonates is …

Plagioclase Studies By Ionoluminescence (Il) And Particle-Induced X-Ray Emission (Pixe) Employing A Nuclear Microprobe, N. P. -O. Homman, C. Yang, K. G. Malmqvist, K. Hanghöj

Scanning Microscopy

When an ion beam in the energy range of a few MeV/amu impacts on a mineral, visible light can often be observed. This light, termed ionoluminescence (IL), has been shown to be a very useful tool for investigating geological specimens when it is combined in a nuclear microprobe with a well-established, quantitative, trace element method such as Particle Induced X-ray Emission (PIXE). When plagioclases from the Skaergaard intrusion, East Greenland, were irradiated with protons, bluish luminescence was observed. Spectroscopic IL studies were undertaken with 1.5 and 2.5 MeV protons with power densities ranging from about 6 to 160 W/cm^{2 …}

Cathodoluminescence Of Some Synthetic Calcite Crystals. Investigation On The Role Played By Cerium, Rémy Chapoulie, Françoise Bechtel, Daniel Borschneck, Max Schvoerer, Guy Rémond

Scanning Microscopy

Cathodoluminescence (CL) from undoped and cerium-doped synthetic calcite is examined at room temperature and at liquid nitrogen temperature, using a scanning electron microscope. At room temperature, all of the samples exhibit a CL emission in the near ultra-violet (UV), centered at approximately 370 nm with some possible shoulders at 345 nm. At low temperature, the samples show an emission of CL in the near UV but with two well defined maxima for the Ce-doped crystals (460 ppm and 4600 ppm) peaking at 345 and around 380 nm. The third Ce-doped crystal (1.74%) presents a maximum at 375 nm and a …

Multi-Laboratory Results For The Cathodoluminescence Emission Spectrum From A Synthetic Zircon Standard, John M. Hanchar, Donald J. Marshall

Scanning Microscopy

The Standards Committee of the Society for Luminescence Microscopy and Spectroscopy (SLMS) circulated doped zircon crystals as a standard for comparison of cathodoluminescence (CL) emission spectra obtained at different laboratories. Eleven laboratories have submitted spectra acquired from this standard. The crystals are synthetic zircons doped with 1.4 wt.% of Dy₂O₃

The participating laboratories used a variety of CL instrumentation including cold cathode optical micro-scope attachments, hot cathode optical microscope attachments, and EMPA/SEM-based systems. Two laboratories provided both uncorrected and corrected spectra. All other spectra are uncorrected. A variety of different spectrometers/spectrographs and detector systems were used. Photomultiplier …

Can Cathodoluminescence And Scanning Electron Acoustic Microscopy Be Considered Complementary Techniques?, J. F. Bresse

Scanning Microscopy

Cathodoluminescence (CL) and Scanning Electron Acoustic Microscopy (SEAM) give complementary information on direct bandgap semiconductors when dopant impurities are introduced. CL deals with the electrical properties of the semiconductor and SEAM deals with the thermal and elastic properties and eventually with the piezoelectric properties in low doped III-V compounds. As function of the introduction of impurities for the doping of the semiconductor, the Near-Band-Edge (NBE) CL emission increases up to a maximum. and decreases when the impurities are no longer introduced in electrically active sites, but create complexes giving rise to the appearance of a Deep Level (DL) emission. The …

Luminescence Spectroscopy Of Semiconductor Surfaces And Interfaces, L. J. Brillson, S. Chang, A. D. Raisanen, I. M. Vitomirov

Scanning Microscopy

Low energy cathodoluminescence spectroscopy (CLS) employing incident electron energies in the range of a few kV or less enable measurement of electronic structure near semiconductor surfaces and interfaces. Coupled with photoluminescence spectroscopy (PL), the CLS technique has been extended to characterize electronic structure tens of nanometers below the free surface at metal-semiconductor and semiconductor-semiconductor junctions. CLS has revealed discrete, deep electronic states for clean and metallized semiconductor surfaces as a function of atomic ordering as well as vicinal surfaces as a function of misorientation. A combination of CLS and PL reveals deep level features associated with strain relaxation and dislocations …

Sex And Extinction, Jennifer M. Eckman

Honors Theses, 1963-2015

Sexual reproduction, the process of generating offspring through genetic recombination, is viewed as evolutionarily advantageous to a population by enabling it to respond more readily to environmental change. Support of this hypothesis comes from the observation that the majority of species employ some mode of sexual reproduction. Asexual reproduction is relatively rare, suggesting that these species reduce their chances of survival. This project examines some of the parameters that relate to a population's ability to respond to its environment. Using a program coded in FORTRAN, a Monte Carlo model has been developed to test the role of recombination on population …

Pre- And Post-Zygotic Isolation Between Sibling Species Of Drosophila, Heidi Skundberg

Honors Theses, 1963-2015

Speciation, the process by which new species arise, is not well understood. Even less is known about the underlying genetics of this process. This study examines the level of reproductive isolation between two closely related species, Drosophila melanogaster and D. simulans. All combinations of intra- and inter-specific single-pair matings were set up in a total of 288 crosses. In all cases, intra- specific crosses (controls) were more successful than inter-specific crosses (PD. melanogaster) is the most discriminating (PD. melanogaster, but not when it is D. simulans.

The Influence Of A Bamboo Diet On The Evolutionary Adaptations Of The Giant Panda, Beth A. Pettitt

Honors Theses, 1963-2015

The giant panda (Ailuropoda melanoleuca) of China is, anatomically, a carnivore trying to get by on an herbivorous diet (Dolnick, 1989). While it is a member of the order Carnivora, ninety-nine percent of the panda's feedstuff is bamboo. The giant panda has survived on a bamboo diet for millions of years and throughout its history has evolved numerous adaptations for obtaining and processing this plant efficiently. Various characteristics of bamboo are considered, including: anatomy, strength, cyanogenic capabilities, reproductive cycle, nutrition and abundance. Following these characteristics, specific adaptations that appear to correspond with these properties of bamboo are examined. …

Regulating Factors Of Ovarian Development In Paper Wasps Of The Genus Polistes, Jean Mengelkoch

Honors Theses, 1963-2015

Wasps of the genus Polistes were used to determine the effects of larval nutrition, position within the nest, and parasitism on ovarian development. Polistes nests were collected from Iowa, Minnesota, and Utah during the summer of 1994. The wasps were reared out, dissected, and their ovaries examined. The total number of oocytes and the size of the largest oocyte were used as measurements of ovarian development. Due to difficulties hand feeding the larvae, no data was obtained concerning the effect of larval nutrition on ovarian development. Data from first emergence nests of Minnesota were inconclusive. However, data from the second …

Transmittance Electron Microscopy: A Comparison Of The Rotifers Asplanchna Herricki And Asplanchna Brightwelli, Nichole M. Hecimovich

Honors Theses, 1963-2015

The rotifers, A. brightwelli and A. herricki were surveyed under SEM and TEM. The overall external features were compared under SEM to determine significant differences in morphology. The widths of the coronal surface and midsection were larger in A. herricki than that of A. brightwelli. A. herricki was prepared for view under E M , and integument was compared to A. brightwelli. The integument of A. brightwelli was substantially thicker than that of A. herricki, which disagreed with the hypothesis. Further studies must be conducted to determine the nature of this difference.