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Cryo-Preparation And Planar Magnetron Sputtering For Low Temperature Scanning Electron Microscopy, T. Müller, P. Walther, C. Scheidegger, R. Reichelt, S. Müller, R. Guggenheim

Scanning Microscopy

Cryo-preparation is a reliable technique for the structural investigation of food products in low temperature scanning electron microscopy (SEM). Artifacts, such as, the segregation of water/non-water ingredients, occur during the freezing process by the crystallization of ice; they can be helpful for correct interpretation of visualized details, e.g., the detection of water containing compartments. The size of the segregation structures depends on water concentration and specimen thickness. The condensation of water vapor (ice contamination) is influenced by the specimen temperature and the partial pressure of the water inside the vacuum system. Furthermore, the evaporation (sublimation, etching) of specimen water can …

The Morphology Of Synovial Lining Of Various Structures In Several Species As Observed With Scanning Electron Microscopy, Peter J. Steinberg, Kees C. Hodde

Scanning Microscopy

Data concerning surface morphology of synovial lining of tendons, tendon sheaths, cruciate ligaments, infra-patellar fat pads and peripatellar synovial ridges in various species (rat, rabbit, dwarf goat, sheep, pig, dog, human) are reported on. Supportive studies with transmission electron microscopy (TEM) and light microscopy were performed.

Three principal morphological appearances of the synovium are evident. On structures with a dense fibrous architecture like tendons, tendon sheaths and cruciate ligaments the intimal cells and processes are mostly slender and may tend to orientation in the length-axis of the structure. On the peri- and infrapatellar adipose tissues two principal 'extremes' are seen: …

The Microvasculature Of The Guinea Pig Ureter. A Scanning Electron Microscopic Investigation, S. Aharinejad, A. Lametschwandtner, W. Höltl, W. Firbas

Scanning Microscopy

In 24 albinotic guinea pigs (Cavia porcellus) the gross vasculature and the microvascular architecture of the ureter were studied by light microscopy of tissue blocks and by scanning electron microscopy of vascular casts. The guinea pig ureter is supplied by the renal artery proximally, by the aorta and the internal iliac artery in its mid-segment, and by the uterine and prostatic as well as by the vesical arteries distally. The main arterial trunks run alongside the ureter before they branch to send perforating arterioles to the muscular coat and the mucosal lining. The draining venules are found on …

Biogeography And Species Density Distributions Of Tasmanian Mammals, Jerry E. Bevers

Dissertations and Theses

Separated from mainland Australia by the Bass Strait, Tasmania has acted as an island preserve maintaining large populations of many mammalian species presently uncommon, rare, or extinct on mainland Australia.

There are few studies of Tasmanian mammal distributions. Recent distributional maps, based on information from surveys and mammal specimens, allowed for an investigation of the species density distributions of the terrestrial mammals of Tasmania. Compilation of species' distributional information into species density distributions provides an overview as to which areas may provide the most significant habitat for the greatest number of species; what geographic variations may influence species distributions; and …

Spatial And Temporal Continuity Of Kangaroo Rat Populations Shown By Sequencing Mitochondrial Dna From Museum Specimens, W. Kelley Thomas, Svante Pääbo, Francis X. Villablanca, Allan C. Wilson

Biological Sciences

The advent of direct sequencing via the polymerase chain reaction (PCR) has opened up the possibility of molecular studies on museum specimens. Here we analyze genetic variation in populations over time by applying PCR to DNA extracted from museum specimens sampled from populations of one species over the last 78 years. Included in this study were 43 museum specimens of the Panamint kangaroo ratDipodomys panamintinus from localities representing each of three geographically distinct subspecies. These specimens were originally collected and prepared as dried skins in 1911, 1917, or 1937. For each specimen, a 225-bp segment of the mitochondrial genome …

Circadian Fluctuations Of Period Protein Immunoreactivity In The Cns And Visual System Of Drosophila, D. M. Zerr, J. C. Hall, M. Rosbash, Kathleen King Siwicki

Biology Faculty Works

When the protein encoded by the period (per) gene, which influences circadian rhythms in Drosophila melanogaster, was labeled with an anti- per antibody in adult flies sectioned at different times of day, regular fluctuations in the intensity of immunoreactivity were observed in cells of the visual system and central brain. These fluctuations persisted in constant darkness. Time courses of the changing levels of staining were altered in the per-short mutant: in light/dark cycles, the phase was earlier than in wild-type, and in constant darkness the period was shorter. In a per-long mutant and in behaviorally subnormal germline transformants (involving transduced …

Vitello-Lipid And Vitello-Protein Deposition In Environmentally Stressed And Non-Stressed Populations Of Morone Saxatilis (Striped Bass), David Van Grimes

Master's Theses

Summer somatic indices of three and four year old striped bass (Morone saxatilis) from Lake Anna (LA), Virginia, a cooling water reservoir, indicated prey ingestion was not sufficient to maintain growth during summer months when striped bass metabolism was elevated by thermal and hypoxic stress. Vitello-lipid and vitello-protein concentrations of stressed LA striped bass were compared to those of non-stressed striped bass from Smith Mountain Lake (SML) , Virginia, a hydroelectric reservoir. Seasonal comparisons of LA and SML striped bass vitello-lipid concentrations and vitello-protein concentrations showed no significant differences between sites (P [less than or equal to] 0.05). Vitello nutrients …

The Mayfly Newsletter, Peter M. Grant

The Mayfly Newsletter

The Mayfly Newsletter is the official newsletter of the Permanent Committee of the International Conferences on Ephemeroptera.

Red-Bellied Woodpecker Predation On Nestling House Wrens, Given Harper, Andrew Neill

Scholarship

No abstract provided.

Electrophysiology, Cell Calcium, And Mechanisms Of Hepatocyte Volume Regulation, Walid E. Khalbuss

Electronic Theses and Dissertations

The electrophysiologic technique (Reuss, L., Proc. Natl. Acad. Sci. USA 82:6014, 1985) was modified to measure changes in steady-state hepatocyte volume during osmotic stress. Hepatocytes in mouse liver slices were loaded with tetramethylammonium ion (TMA$\sp{+}$) during transient exposure of cells to nystatin. Intracellular TMA$\sp{+}$ activity (a$\sp{\rm i}\sb{\rm TMA}$) was measured with TMA$\sp{+}$-sensitive, double-barreled microelectrodes. Loading hepatocytes with TMA$\sp{+}$ did not change their membrane potential (V$\sb{\rm m}$), and under steady-state conditions a$\sp{\rm i}\sb{\rm TMA}$ remained constant over 4 min in single impalements. Hyperosmotic solutions (50, 100, & 150 mM sucrose added to media) and hyposmotic solutions (sucrose in media reduced by …

Molecular Mechanisms Of Physalia Physalis Venom Modulation Of Cardiac And Vascular Functions, Eva Luo

Loma Linda University Electronic Theses, Dissertations & Projects

Portuguese man-of-war (Physalia physalis)venom has profound effects on the cardiovascular system of man and animals. The venom produces vascular relaxation in norepinephrine precontracted, intact rabbit femoral arterial rings by stimulating vasodilatory prostaglandin synthesis in the endothelium. This action does not depend on endotheliumderived relaxing factor (EDRF). P. physalis venom produces a vascular constriction on KC1 depolarized, intact rings. This is completely inhibited by dibenzyline and yohimbine. Increased membrane permeability to calcium may be involved in direct vascular smooth muscle stimulation. The venom has a positive inotropic effect on rat atrial preparations, which is intensified by increased extracellular calcium concentration. …

A Chronic Toxicity Assessment Of An Industrial Effluent Utilizing Pimephales Promelas And Ceriodaphnia Sp, Sharon J. Whitaker Fugate

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Arts and Sciences at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by Sharon J. Whitaker Fugate on July 23, 1990.

The Electrokaryotype And Molecular Characterization Of Trypanosoma Cervi Isolates Using Recombinant Dna Techniques, J. Lindsley Bennett

Dissertations and Theses

The distribution of trypanosomes infecting wild ruminants of North America has only recently been investigated. Many isolates have been mensurally studied and were determined to be conspecific with Trypanosoma cervi. Widely divergent forms exist however, between host species and seasonally within a host. To determine the validity of all inclusions in the taxon and the extent of intraspecific variability, trypanosome isolates of moose, reindeer, antelope, muledeer, Roosevelt Elk and two discrete transplant populations of Rocky Mountain elk were characterized and differentiated using recombinant DNA techniques.

Ua66/6/2 Bionews From The Hill, Wku Biology

WKU Administration Documents

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

Larval Settlement Of Ilyanassa Obsoleta (Gastropoda) And Capitella Sp. I (Polychaeta): Responses To Sediment Cues And Effects Of No. 6 Fuel Oil, Dianne Rudy '90

Honors Projects

Metamorphosis in response to bottom sediment was measured in two species of marine planktonic larvae. Ilyanassa obsoleta, a common mud-snail, and Capitella sp. I, a polychaete worm. A sediment control consisted of organic-rich sediment collected from Barnstable Harbor, Ma. One sediment treatment, termed muffled sediment, consisted of the sediment control heated at a high temperature in a muffle oven to remove all organic matter. A sharp decrease in percent metamorphosis was observed in larvae exposed to the muffled sediment condition compared to the sediment control. Results confirmed that settlement involves more than physical contact with the sediment and suggest that …

Small Mammals In The Great Dismal Swamp Of Virginia And North Carolina, Robert K. Rose, Roger K. Everton, Jean F. Stankavich

Biological Sciences Faculty Publications

Small" mammals were surveyed in a range of habitats in the Great Dismal Swamp of Virginia and North Carolina. The survey is based on three chronologically overlapping studies, each lasting 15-18 months and for which the results have been reported separately. A different trapping method was used in each of the three studies: nest boxes, Fitch live traps, or pitfall traps. Only two species of mammals, both arboreal, were taken in nest boxes, compared with 10 and 9 species in Fitch live traps and pitfall traps, respectively. The Fitch live traps had a much higher catch rate per 1,000 trap-nights …

Reproduction In The Hispid Cotton Rat, Sigmodon-Hispidus Say And Ord (Rodentia: Muridae), In Southeastern Virginia, Robert K. Rose, Michael H. Mitchell

Biological Sciences Faculty Publications

The hispid cotton rat, Sigmodon hispidus Say and Ord, a species of the southwestern United States that has been moving northward and eastward in this century, was first observed in Virginia in 1940. In this study of the cotton rat in southeastern Virginia, most males were reproductively competent from February through November, embryos were recorded from March through October, and litter sizes were comparable to those from other locations except Kansas. Also unlike the cotton rat in Kansas, animals grew at substantial rates during the winter in Virginia. The hispid cotton rat seems to have adjusted its breeding season in …

Evidence Of A Neurogenic Component During Ige-Mediated Inflammation In Murine Skin, Victoria Jean Cavanaugh

Biological Sciences Theses & Dissertations

The direct stimulation of sensory nerves or the intradermal injection of neuropeptides triggers a cutaneous inflammatory response that involves the degranulation of mast cells. These neurogenic inflammatory reactions are physiologically similar to IgE-mediated hypersensitivity responses, which also depend on mast cells. Although non-antigenic stimuli distinguish neurogenic from IgE-mediated inflammation, the similarity of their effector stages suggested that peripheral nerves may also participate in lgE-mediated responses. To examine this hypothesis, IgE responses were elicited in denervated skin. A murine model was developed where the footpad was denervated by surgically removing a 2 mm segment of the sciatic nerve, proximal to the …

Description Of The Tadpoles Of Gastrophryne Pictiventris And Nelsonophryne Aterrima (Anura: Microhylidae), With A Review Of Morphological Variation In Free-Swimming Microhylid Larvae, Maureen A. Donnelly, Rafael O. De Sá, Craig Guyer

Biology Faculty Publications

The tadpoles of Gastrophryne pictiventris and Nelsonophryne aterrima are described based on material collected in Costa Rica and Panama, respectively. The tadpole of G. pictiventris resembles those of the other species of Gastrophryne. The tadpole of N. aterrima differs from other New World microhylid tadpoles in location of the vent tube (medial), the spiracular opening (ventral to the gut), and eyes (dorsolateral). The unique configuration of mouthparts in N. aterrima is described. Morphological variation in microhylid tadpoles is reviewed and six larval characters are analyzed cladistically for IO New World microhylid genera.

Temporal Changes In The Ommatidial Structure Of The Cockroach, Leucophaea Maderae, Becky Reitcheck

Masters Theses & Specialist Projects

A circadian rhythm in eye sensitivity to light has been previously reported for Leucophaea maderae. Temporal changes in eye cell morphology that could be correlated with those changes in eye sensitivity to light were examined. Rhabdom area, screening pigment organization and palisade layer area about the rhabdom were the parameters measured to detect structural change through time. Measurements of those parameters from tissue samples obtained from the anterior one-third of compound eyes surgically removed at midday, light offset, midnight and light onset from roaches entrained to a 12-h light / 12-h dark photoperiodic cycle were used to assess the …

Characterization And Expression Of The Cbbe' Gene Of Coxiella Burnetii, Michael F. Minnick, Robert A. Heinzin, Marvin Eugene Frazier, Louis P. Mallavia

Biological Sciences Faculty Publications

A gene which is unique to the QpRS plasmid from chronic isolates of Coxiella burnetii was cloned, sequenced, and expressed in Escherichia coli. This gene, termed cbbE', codes for a putative surface protein of approximately 55 kDa, termed the E' protein. The cbbE' gene is 1485 bp in length, and is preceded by predicted promoter regulatory sequences of TTTAAT (-35), TATAAT (-10), and a Shine-Dalgarno sequence of GGAGAGA, all of which closely resemble those of E. coli and other rickettsiae. The open reading frame (ORF) of cbbE' ends with a UAA codon followed by a second in-frame UAG stop codon …

Chromatin Structure And Gene Activity, Sarah C.R. Elgin

Biology Faculty Research

No abstract provided.

Boll Weevil Testis-Specific Cdna, Patrick M. Trewitt, Larry J. Heilmann, A. Krishna Kumaran

Biological Sciences Faculty Research and Publications

No abstract provided.

Fisheries Research Report No 88 - A Synopsis Of The Biology And The Exploitation Of The Australiasian Pilchard, Sardinops Neopilchardus (Steindachner) Part 1: Biology, W. J. Fletcher

Fisheries Research Reports

There have been a large number of studies which relate to the biology and exploitation of the Australian pilchard, Sardinops neopilchardus. Much of the data, however, are located in journals which are hard to obtain, or in unpublished reports, and theses. With the increase in catch of pil­chards, particularly in Western Australia, a collation of all the available knowledge pertaining to pilchards in Australia and New Zealand was desired to help with the planning of future research into the Western Australian stocks of this species. This report contains all the information located on the biology of Sardinops neopilchardus, a companion …

The Short-Term Effects Of Manganese Toxicity On Ribulose 1,5 Biophosphate Carboxylase In Tobacco Chloroplasts, Kerrie Elliott

Masters Theses & Specialist Projects

The short-term effects of manganese toxicity on ribulose 1,5 bisphosphate carboxylase (Rubisco) activity and concentration in tobacco chloroplasts were examined. The activity of the enzyme from both manganese-treated and control plants was determined 6, 12, 18, 24 , and 48 h after introduction of manganese (80 mg/Li. Enzyme activity was determined by monitoring rates of radioactive CO₂ fixation into acid stable products. A slight stimulation of the enzyme's activity was noted in experimental plants after 18 h of exposure to manganese as compared with control plants. A decrease in the enzyme's activity in experimental plants was noted after 48 …

Seasonal Fluctuations Of Thermophilic And Psychrophilic Bacteria In Westhampton Lake, Richmond, Virginia, Chukwukere Godwin Durunna

Master's Theses

This study was based on the hypothesis that the populations of thermophilic, mesophilic, and psychrophilic bacteria in Westhampton Lake vary seasonally and are related to prevailing temperatures. It may be inferred that the kinds of bacteria present at a given season are those most directly involved in decomposition and recycling activities in the lake. Water samples were collected biweekly from September of 1986 through mid- August 1987 at three stations in Westhampton Lake. At each station, sample depths ranged from near the surface to near the bottom. Serial dilutions were plated in duplicate on nutrient agar and were incubated at …

Conservation Of Intron Position Indicates Separation Of Major And Variant H2as Is An Early Event In The Evolution Of Eukaryotes, A Van Daal, E White, Sarah C.R. Elgin, M Gorovsky

Biology Faculty Research

Genomic clones of Drosophila and Tetrahymena histone H2A variants were isolated using the corresponding cDNA clones (van Daal et al. 1988; White et al. 1988). The site corresponding to the initiation of transcription was defined by primer extension for both Drosophila and Tetrahymena genomic sequences. The sequences of the genomic clones revealed the presence of introns in each of the genes. The Drosophila gene has three introns: one immediately following the initiation codon, one between amino acids 26 and 27 (gln and phe), and one between amino acids 64 and 65 (glu and val). The Tetrahymena gene has two introns, …

Enhancement And Monitoring Of The Procambarus Clarkii Population In Lake Mead, Mikell Beth Hager

Publications (WR)

Procambarus clarkii are found in extremely low numbers throughout Lake Mead, AZ-NV. The crayfish are an important dietary component for game fish. Enhancement of the crayfish population would broaden the fishery forage base. Crayfish were stocked and monitored in a study cove on Saddle Island to determine if the Procambarus clarkii population could be enhanced. A trapping survey of the area after the following reproductive season yielded low numbers of crayfish. A comparison of pre-stocking and post-stocking catch per trap day (CPTD) values revealed no significant increase in the population. Procambarus clarkii growth is limited by environmental factors in Lake …

Immunological Effects Of Ketoconazole, Itraconazole And Fluconazole On Lymphocyte Cell Proliferation And Natural Killer Cell Activity In Immune-Normal, Cyclosporine-Compromised And Cyclophosphamide-Compromised Mouse Models, Jeffrey Tullis Mitchell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Over the past several years there has been a steady increase in the incidence of immunologically compromised patients. This has been the result of both chemical agents, such as those used in cancer chemotherapy, and biological agents such as HIV, the cause of Acquired lmmunodefeciency Syndrome (AIDS). The increase in immune-suppressed patients has lead to an increase in life-threatening mycoses requiring treatment with antifungal agents. Pharmaceutical companies have increased research for the development of new antifungal agents which are more effective and less toxic than those that are currently used. Several researchers have reported on antifungal agents that demonstrate both …

Effect Of Copulation And Copulation Time On Female Reproductive Development In Diabrotica Virgifera Virgifera (Coleoptera: Chrysomelidae), David Sherwood '90

Honors Projects

It has been established that a prolonged copulatory period of 3-4 hours is necessary for maximal insemination to occur in the western corn rootworn (WCR). This complete mating period has been suggested to speed ovarian development. The purpose of this study was to determine the relationship between copulation and ovarian development in the WCR. Using 11 and 12 day postemergence virgin WCR beetles, four female groups of varying copulatory duration were established: (1) 15 min. in copula (2) 1 hr. in copula (3) 2 hrs. in copula (4) a control group mated until natural completion. After copulation, these beetles along …