Biology Commons^™

Ua66/6/3/1 Biennial Report, Kentucky Gamma, Alpha Epsilon Delta

Student Organizations

Biennial report created by and about the Kentucky Gamma Chapter of Alpha Epsilon Delta premedical honor society sponsored by WKU Biology.

Microbeam Studies Of The Sensitivity Of Structures Within Living Cells, L. A. Braby

Scanning Microscopy

Determining the biological effects of low doses of radiation with high linear energy transfer (LET) is complicated by the stochastic nature of charged-particle interactions. Populations of cells exposed to very low radiation doses contain a few cells which have been hit by a charged particle, while the majority of the cells receive no radiation damage. At somewhat higher doses, a few cells receive two or more events. Because the effects of damage produced by separate events can interact in the cell, we have had to make assumptions about the nature of these interactions in order to interpret the results of …

The Effect Of Colcemid On The Heat Survival Of Mitotic V79 Chinese Hamster Cells, J. G. Szekely, G. P. Raaphorst, A. U. Lobreau, S. Delaney, E. I. Azzam

Scanning Microscopy

V79 Chinese hamster cells were collected by colcemid addition to study the effect of heat on mitosis. When they were heated at 42°C and 45°C in the presence of 0.06 μg/mL colcemid, cell survival increased over the control samples, which were heated in ordinary medium. Scanning electron microscopy showed that cells heated to 45°C in the presence or absence of colcemid had fewer microvilli on the surface, but they did not have increased bleb formation. Transmission electron microscopy showed that the chromatin was diffuse in the heated cells and the kinetochores were indistinct. The mitochondria in the heated cells were …

A Review Of Scanning Tunneling Microscope And Atomic Force Microscope Imaging Of Large Biological Structures: Problems And Prospects, B. L. Blackford, M. H. Jericho, P. J. Mulhern

Scanning Microscopy

The application of the scanning tunneling microscope (STM) and the atomic force microscope (AFM) to the study of small biological molecules, such as DNA and smaller molecules, has received considerable attention in the literature. This paper reviews STM and AFM studies of larger biological structures such as bacterial membranes, bacteriophages, viruses, antibodies, etc. The problems encountered in these applications are emphasized, with particular reference to the unknown conduction mechanism, tip-sample interaction forces, and tip-sample convolution artifacts in the images. The latter problem is illustrated by new results from IgG antibody complexes attached to a bacterial sheath layer. A new conduction …

The Microvasculature Of Human Oral Mucosa Using Vascular Corrosion Casts And India Ink Injection I. Tongue Papillae, Q. X. Yu, W. Ran, K. M. Pang, H. P. Philipsen, J. Theilade, X. H. Chen, Y. C. Mok

Scanning Microscopy

The microvasculature of human tongue papillae originating from 9 males and 6 females, aged 0.5 to 2 years was studied by scanning electron microscopy (SEM) of vascular corrosion casts and by light microscopy (LM) of India ink injected specimens. All papillae showed a microvasculature characterized by primary, secondary and tertiary capillary loops. In the filiform papillae the loops were generally arranged in a corolla-like pattern with the tertiary loops demonstrating a hair-pin shape. The fungiform papillae showed basically a similar architectural pattern although the loops were somewhat more compact and complex in structure. A small, shallow depression of the tertiary …

Increasing Resolution And Versatility In Low Temperature Conventional And Field Emission Scanning Electron Microscopy, William P. Wergin, Eric F. Erbe

Scanning Microscopy

Studies were undertaken to expand the versatility and the resolution of low temperature conventional and field emission scanning electron microscopy (SEM). The results indicated that simple modified specimen holders, which could be used in conjunction with the commercial cryosystems, allowed one to store specimens for several weeks in liquid nitrogen, either before or after observation in a conventional SEM, without incurring degradation of the surface features. Other modified holders permitted one to move the specimen closer to the final lens or to use the upper secondary electron detector, which is available with some SEMs. Both of these procedures increased the …

New Directions In Scanning Electron Microscopy Cathodoluminescence Microcharacterization, D. B. Holt

Scanning Microscopy

The general principles of the low-temperature spectroscopic cathodoluminescence (LTSCL) technique in the scanning electron microscope (SEM) are outlined. CL microscopy and spectroscopy are now being extended in new directions. Analysis of the intrinsic CL from quantum well materials by LTSCL is proving valuable for microcharacterization and such work can be expected to expand rapidly. The main, early CL results in this exciting field are summarized here. In geology, CL microscopy, without spectroscopy, is widely used via electron-beam attachments to light microscopes and the addition of spectral analysis to these studies is overdue. Much CL from minerals and ceramics comes from …

Tooth Tissues Of Certain Sharks And Lungfishes, Yasutomo Iwai-Liao, Yoshikage Higashi, Yoshitaka Tamada

Scanning Microscopy

A comparative odontologic study was conducted on teeth and their supporting tissues from extant sharks, fossil sharks, and living lungfishes using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) X-ray microprobe to investigate evolutionary changes in tooth structure of the fishes.

No histological differences between the extant and fossil teeth of lamnoid sharks were observed. The weight percent of calcium in osteodentin of the fossil shark was higher than that in the extant shark. The weight percents of both P and Ca of tooth tissues in the giant extinct shark showed comparatively low values.

Both the upper and lower …

Effects Of Conalbumin Bound Iron On The Growth Of Salmonella Paratyphi B And Salmonella Thompson, John Nicholas Mason

Dissertations and Theses

I have investigated the possibility that specific conalbumin (ovotransferrin) iron saturation levels enable less virulent strains of Salmonella to become more virulent. Iron starved cells of two pathogenic Salmonella strains, S. paratyphi B var. java and S. thompson, were cultured in iron limited media at 3 different iron conalbumin saturation levels. Results indicate that strains differ significantly at both low and high iron saturation conalbumin. These differences depict a growth advantage for S. paratyphi B which correlates with reports by the Centers for Disease Control that S. paratyphi B was 3 times more frequent in blood isolates than S. …

Calcium Oxalate Crystal Growth In The Presence Of Mucin, Mostafa Akbarieh, Rashad Tawashi

Scanning Microscopy

Using interfacially-controlled crystallization and gel diffusion crystallization methods, calcium oxalate monohydrate (COM), dihydrate (COD) and trihydrate (COT) crystals were grown by the slow diffusion of reacting ions in the presence of mucin. It was demonstrated that mucin in the growth media dramatically affected the size, habit, surface structure, thermodynamic stability and phase transition kinetics of hydrated calcium oxalate crystals. The results obtained revealed that mucin as a glycoprotein model controlled the growth of COT and COD single crystals as well as cluster formation. Growth inhibition of specific crystal faces and phase transition retardation occurred in its presence. The data confirmed …

Panchromatic And Spectral Characterization Of Cu Contaminated Semi-Insulating Gaas, Thomas E. Zirkle, Stephan Myhajlenko, Nam Soo Kang, Ronald J. Roedel, Dieter K. Schroder

Scanning Microscopy

Panchromatic (integral) and spectrally resolved cathodoluminescence characterization was used to investigate the near surface gettering properties of Cu in liquid-encapsulated, Czochralski-grown, undoped semi-insulating (SI) GaAs. Samples from two sources were investigated to determine if gettering treatments applied to GaAs result in improvements in uniformity similar to those observed in gettered Si. Before Cu contamination, typical cellular structure is observed for all samples. Experimentally, it is found that the panchromatic CL images change significantly after Cu doping and subsequent gettering processing for all samples. A contrast reversal is generally observed after Cu contamination. After gettering, the image of the samples from …

Consumption Rates, Evacuation Rates And Diets Of Pygmy Killifish, Leptolucania Ommata, And Mosquitofish, Gambusia Affinis In The Okefenokee Swamp, J. Douglas Oliver

Faculty Publications and Presentations

I studied feeding dynamics of Leptolucania ommata and Gambusia affinis in the Okefenokee Swamp. Both fishes mainly ate insect larvae (such as Chironomidae) and Cladocera. Evacuation rates ranged from 0.143 (L. ommala in winter) to 0.279/hour (L. ommala in summer). Daily food consumption (dry weight) ranged from 24.2 (L. ommata in winter) to 148.3 mg/g/day (G. affinis in summer). Maximum consumption by both species was estimated at 26.31 mg/t m2 / day, in summer. These values are consistent with other observations supporting a hypothesis that invertebrate prey production is substantial in these blackwater wetlands.

A Plasmid-Encoded Surface Protein Found In Chronic-Disease Isolates Of Coxiella Burnetti, Michael F. Minnick, Robert A. Heinzin, Dennis K. Reschke, Marvin Eugene Frazier, Louis P. Mallavia

Biological Sciences Faculty Publications

The cbbE' gene codes for the E' protein of Coxiella burnetii and was detected in genomic DNA from all known human isolates of the biotzere strain but not in DNA from the other five strains of C. burnetti. The biotzere strain is strictly associated with chronic disease in humans. Extrinsic iodination of biotzere strain cells radiolabeled a 55-kDa protein which comigrated on sodium dodecyl sulfate-polyacrylamide gel electrophoresis with the E' protein synthesized in vitro from recombinants containing the cbbE' gene. The 125I-labeled 55-kDa protein was immunoprecipitated with polyclonal anti-E' antiserum, confirming its identity as E'. Predicted secondary structure of the …

Breeding Biology Of A Southeastern Population Of Tree Swallows Tachycineta Bicolor, Denise Stephens

Masters Theses & Specialist Projects

An Ohio County, Kentucky, population of Tree Swallows utilizing nest boxes located over a strip pit lake on reclaimed Peabody Coal Company land was studied on a weekly basis throughout its breeding season. The season lasted from late April to late July. Dates and/or numbers were recorded regarding nest building, egg laying, clutch size, hatching and fledging success, age of females and adult activity at the nest in order to make comparisons with these data collected in studies of more northern populations. In addition, incubating females were color marked in order to determine if they produced a second clutch. No …

Epistomatal Wax Injury To Red Spruce Needles (Picea Rubens Sarg.) Grown In Elevated Levels Of Ozone And Acidified Rain, C. R. Krause, W. N. Cannon Jr.

Scanning Microscopy

Red spruce seedlings (Picea rubens Sarg.) were exposed to charcoal-filtered air, at 0.07 ppm or 0.15 ppm ozone (O₃), alone or in combination with pH 4.2 or pH 3.0 acidified rain, and examined with scanning electron microscopy (SEM) to determine if epistomatal wax fine structure was affected. Acidified rain in combination with 0.15 ppm O₃ produced changes in wax tubule morphology. Changes were moderate at pH 4.2 and severe at pH 3.0. Needles collected from Whiteface Mountain, New York, displayed injured epistomatal wax structure similar to that observed on needles exposed in the laboratory to 0.15 …

Variation In A Host-Epiphyte Relationship Along A Wave Exposure Gradient, Phillip S. Levin, Arthur C. Mathieson

New Hampshire Agricultural Experiment Station Publications

The red alga Polysiphonia lanosa (L ) Tandy is an obligate epiphyte that primarily occurs on the fucoid brown algal basiphyte Ascophyllum nodosum (L) Le Jolis In the present study we examine how epiphytic interactions between P lanosa and A nodosum vary along a wave exposure gradient within the southern Gulf of Maine, USA P lanosa was most dense on protected shores, however because the stature of P lanosa was greater on exposed than on sheltered shores, greater biomass occurred In exposed habitats Epiphytlc P lanosa pnmanly attached to inlured vegetative bssue at exposed sites, while ~ t osc currence …

Population Ecology Of Polydora Ligni (Polychaeta: Spionidae). I. Seasonal Variation In Population Characteristics And Reproductive Activity, Roman Zajac

Biology and Environmental Science Faculty Publications

A population of the polychaete Polydora ligni Webster was studied during 1982 and 1983 in Alewife Cove, Connecticut, USA, to determine seasonal changes in population characteristics. During early spring (March and April), the population was comprised of primarily large adults that had over-wintered. Females in this group exhibited the highest mean individual fecundity over the year (> 2000 larvae per brood). However, total larval production at this time was low (5200 to 208 000 larvae m^-2 per 14 d) due to low densities of adults. Population density increased slowly during spring as juveniles produced by overwintering adults recruited into …

Population Ecology Of Polydora Ligni (Polychaeta: Spionidae). Ii. Seasonal Demographic Variation And Its Potential Impact On Life History Evolution, Roman Zajac

Biology and Environmental Science Faculty Publications

Seasonal demographic variation was studied in an estuarine population of the opportunistic polychaete Polydora ligni between May 1982 and November 1983 in Alewife Cove, Connecticut, USA. The demography of 15 cohorts settling during this period was analyzed using life cycle graph models. Cohorts settling in spring and early summer had the shortest life spans (≈ 10 wk); highest survivorship over all life cycle stages and adult females produced an estimated maximum of 6 larval broods. Early adult stages contributed most to population growth during this period, and the potential for population growth, λ, was the highest during the study. Late …

Optimization Design For The Electron Emission System Using Improved Powell Method, Chang-Xin Gu, Li-Ying Shan, Zhi-Rong Chen

Scanning Microscopy

The electron emission system, which may mostly decide the main properties of the whole electron optical system, is a crucial element for an electron gun. The design of the electron emission system is more important compared with other electron lenses in the electron gun. In this paper, an optimization design method for the electron emission system is presented by using an Improved Powell Method with linear search for the one dimensional search. The optimal structure parameters with a criterion of minimum objective function value for this system are provided. The computed results may show that this direct search optimization method …

Correlation Of Cochlear Pathology With Auditory Brainstem And Cortical Responses In Cats With High Frequency Hearing Loss, R. J. Mount, R. V. Harrison, S. G. Stanton, A. Nagasawa

Scanning Microscopy

Newborn kittens were treated with the aminoglycoside amikacin to produce a bilateral high frequency cochlear hearing loss. The degree and stability of hearing loss were confirmed by recording auditory brainstem evoked potentials (ABR audiograms). After maturation, cochleotopic frequency representation within primary auditory cortex (Al) was mapped using standard microelectrode recording techniques. The cochlear sensory epithelium was assessed with SEM and the pattern of damage compared with the ABR audiograms and cortical frequency maps.

Amikacin treatment resulted in various patterns of haircell damage towards the base of the cochlea. A relatively abrupt transition between damaged and undamaged haircell regions resulted in …

An Integrated Study Of The Morphological And Gross-Elemental Consequences Of Methyl Mercury Intoxication In Rats, With Particular Attention On The Cerebellum, K. Leyshon, A. J. Morgan

Scanning Microscopy

Methylmercury accumulates in the kidney and liver of rats, but fairly selectively damages the cerebellum, resulting in the clinical symptoms of neurological ataxia after prolonged exposures. Within the cerebellum, morphological examination indicated that the small granule cells beneath the Purkinje layer are especially susceptible to the toxin, showing signs of pyknosis during the phase of locomotory disability, whilst the large Purkinje cells are relatively resistant to cytotoxic injury. Flame photometric and electron probe X-ray microanalysis (EPXMA) of digested samples of the major organs failed to detect any significant changes in the Na, K, Ca, Mg, S and P concentrations of …

Application Of The Nuclear Microprobe To The Imaging Of Single Event Upsets In Integrated Circuits, K. M. Horn, B. L. Doyle, D. S. Walsh, F. W. Sexton

Scanning Microscopy

A new form of microscopy has been developed which produces micron-resolution maps of where single event upsets occur during ion irradiation of integrated circuits. Utilizing a nuclear microprobe, this imaging technique can irradiate, in isolation, individual components of an integrated circuit (e.g. transistor drains, gates, feedback resistors) and measure immediately the effect of a high energy ion strike on circuit performance. This detailed circuit characterization technique provides a precision diagnostic with which to evaluate the design of integrated circuits that are to be used in space or other radiation environments.

A Drosophila Melanogaster H3.3 Cdna Encodes A Histone Variant Identical With The Vertebrate H3.3, Scott Fretzin, Barbara D. Allan, Angela Van Daal, Sarah C.R. Elgin

Biology Faculty Publications & Presentations

A cDNA encoding an H3.3 histone variant in Drosophila melanogaster predicts a protein with an amino acid (aa) sequence identical with that in vertebrates. The D. melanogaster H3.3 nucleotide (nt) sequence has diverged significantly from that of both the H3.3 gene of vertebrates and the H3.1 gene of D. melanogaster, largely through third nt changes in its codons. The perfect H3.3 aa sequence conservation between organisms as phylogenetically divergent as vertebrates and flies suggests that the H3.3 histone variant itself is an important structural component of chromatin, apart from the value of its replication-independent expression pattern. Keywords: Conserved proteins, amino …

Analysis Of The Metal Requirement Of 3-Deoxy-D-Arabino-Heptulosonate-7-Phosphate Synthase From Escherichia Coli., Craig Stephens, Ronald Bauerle

Biology

The three isozymes of 3-deoxy-D-arabino-heptulosonate-7-phosphate synthase from Escherichia coli were overproduced, purified, and characterized with respect to their requirement for metal cofactor. The isolated isozymes contained 0.2-0.3 mol of iron/mol of enzyme monomer, variable amounts of zinc, and traces of copper. Enzymatic activity of the native enzymes was stimulated 3-4-fold by the addition of Fe2+ ions to the reaction mixture and was eliminated by treatment of the enzymes with EDTA. The chelated enzymes were reactivated by a variety of divalent metal ions, including Ca2+, Cd2+, Co2+, Cu2+, Fe2+, Mn2+, Ni2+, and Zn2+. The specific activities of the reactivated enzymes varied …

Surface Topographical And Compositional Characterization Using Backscattered Electron Methods, Dirk A. Wassink, Jerry Z. Raski, Joel A. Levitt, David Hildreth, Kenneth C. Ludema

Scanning Microscopy

Two pairs of diametrically opposed Schottky surface barrier diodes in a modified scanning electron microscope (SEM) are used to reconstruct surface elevations and composition differences. An empirically determined function of difference of signals from opposing diodes is used to calculate slopes, which are then integrated to elevations by an efficient 2-dimensional Fast Fourier Transform. Composition differences are distinguished by variations in the overall backscattered electron (BSE) intensity estimated by the sum of the four diode signals. Arithmetic average roughness measurements from the BSE device are within 10% of stylus surface tracer measurements when surface slopes average less than 6 degrees …

Microscopy Of Mixed Surfaces On Layered Semiconductors, L. Margulis, D. Mahalu, B. Parkinson, R. Tenne

Scanning Microscopy

A large number of well-defined hexagonal etch pits is produced on the WSe₂ surface by controlled anisotropic corrosion. As a result a mixed surface (combining both ⊥c and ||c components) is created. This surface exhibits photovoltaic properties even better than the atomically smooth van der Waals surface. Measurements of electron beam induced current performed at low temperatures give direct evidence for enhanced current collection of ||c facets. Observations made by transmission electron microscopy and scanning tunneling microscopy show the presence of very low ||c steps on the van der Waals surface.

Seed Testa Morphology Of 18 Species Of Rafnia Thunb. (Fam. Fabaceae, Sub-Family Papilionoideae), G. R. Richardson, R. Cross

Scanning Microscopy

Scanning electron microscopy was used to conduct a micromorphological study of testae of the seeds of 18 species of Rafnia Thunb. (Fam. Fabaceae, Sub-family Papilionoideae). The testa patterns revealed diagnostic taxonomic features which proved useful in the construction of a key for the identification of the various Rafnia species. Comparisons between air-dried freshly collected, and long-term stored herbarium specimens revealed that testa patterns remained consistent and valid for taxonomic purposes.

Electron Beam Induced Current Investigations Of Electrical Inhomogeneities With High Spatial Resolution, Eu. Yakimov

Scanning Microscopy

Electron beam induced current (EBIC) microscopy is a very promising SEM technique for the study of diffusion length and depletion region width inhomogeneities with high spatial resolution. However, this resolution is limited by the dimensions of the electron-hole pair generation region. In this paper the possibilities to improve spatial resolution are discussed. Electron beam tomography, i.e. the reconstruction of physical property distributions from sets of two-dimensional images, seems to be the most promising for this purpose. It is shown that in the case of dislocations it is possible to obtain information about dislocation impurity atmosphere parameters from EBIC measurements. The …

Micro-Pixe (Particle-Induced X-Ray Emission Analysis) Applications In Minerals Research, S. H. Sie, C. G. Ryan, G. F. Suter

Scanning Microscopy

The versatility of the PIXE method with microbeams of protons as a non-destructive, in-situ probe for trace element analysis in the geosciences has been demonstrated in an ever increasing number of cases. While in most applications the method can be considered as derivative or as an extension of electron microprobe methodology, features unique to the proton microprobe enable new approaches to hitherto intractable problems of analysis. An appropriate niche has been established in igneous mineralogy and petrology, with important implications both in the basic geosciences as well as mineral industry applications, particularly in the diamond exploration industry. This paper reviews …

The Development Of The Vascular System In Quail Embryos: A Combination Of Microvascular Corrosion Casts And Immunohistochemical Identification, M. C. Deruiter, B. Hogers, R. E. Poelmann, L. Vanlperen, A. C. Gittenberger-De Groot

Scanning Microscopy

Although vascular casts, obtained by injection with methacrylates, are frequently used to investigate the adult vascular system, little data are available for embryonic stages. In this paper we use Mercox^R in quail embryos in the period of 2 to 7 days after incubation. The microvascular corrosion casts were evaluated in the scanning electron microscope (SEM) with special attention to the development and remodelling of the large arteries and veins. Our results show that the remodelling of the large arteries and veins together with their developing tributary vessels can be visualized from very early embryonic stages onwards. However, complete replication …