Digital Commons Network^™

Recovery Of Vegetation Following A Wildfire In A Barrier Island Grassland, Padre Island National Seashore, Texas, Robert I. Lonard, Frank W. Judd, Elizabeth H. Smith, Chenghai Yang

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Vegetation recovery following a wildfire in vegetated flats and secondary dunes of Padre Island National Seashore, Texas, was studied from January 2000 to January 2002. Species richness, diversity, evenness, abundance, and importance were evaluated. Species richness, diversity, and evenness were restored quickly in vegetated flats (51 days) and secondary dunes (71 days). The burned secondary dune site had the same dominant species as its non-burned counterpart from the beginning to the end of the study, but it took 106 days for the dominant species to be restored in the burned vegetated flats. No exotic species established in burned sites. Two …

The N-Terminal Prodomain Of Sv23 Is Essential For The Assembly Of A Functional Vitelline Membrane Network In Drosophila, Anita L. Manogaran, Gail L. Waring

Biological Sciences Faculty Research and Publications

The vitelline membrane is a specialized extracellular matrix that surrounds and protects the oocyte. Recent studies indicate that it also serves as a storage site for embryonic pattern determinants. sV23, a major vitelline membrane protein, is essential for the morphogenesis of the vitelline membrane as sV23 protein null mutants lay flaccid, infertile eggs. By analyzing a series of sV23 mutant transgenes in the sV23 protein null genetic background, we have shown that sV23 is secreted as a proprotein in functional excess and that C- and N-terminal prodomains are removed successively, following its deposition in the extracellular space. Although a target …

A New Toad (Anura: Bufonidae) From Uruguay, Raúl Maneyro, Diego Arrieta, Rafael O. De Sá

Biology Faculty Publications

A new species of toad is described from small streams in the hills of Cuchilla de Haedo and Cuchilla Grande in northeastern Uruguay. Specimens of the new species were previously mistaken for Bufo arenarum; they differ from B.arenarum by having elongated parotoid glands and reddish-brown parotoid and cephalic crests. A discriminant analysis resulted in three groups corresponding to B. arenarum, Bufo rufus, and the specimens herein described as a new species.

A Biochemical Study Of Mucus Lysomzyme, Proteins And Plasma Thyroxine Of Atlanctic Salmon (Salmo Salar) During Smoltification, Maresa Fagan

Masters

Atlantic salmon prepare to migrate from fresh water to sea water during a phase of great physiological change known as smoltification. In the context of stock enhancement programmes and the conservation of Atlantic salmon stocks, the release of smolts from freshwater to sea is of major significance. Accordingly, this study set out to monitor some of the physiological and biochemical changes, which allow the Atlantic salmon to migrate from freshwater to seawater. Our research focused on skin mucus as a possible candidate for the development of a non invasive test and sought to elucidate biochemical or significant protein changes in …

Non-Parametric Algorithms For Evaluating Gene Expression In Cancer Using Dna Microarray Technology, Virginie Aris

Dissertations

Microarray technology has transformed the field of cancer biology by enabling the simultaneous evaluation of tens of thousands mRNA expression levels in a single experiment. This technology has been applied to medical science in order to find gene expression markers that cluster diseased and normal tissues, genes affected by treatments, and gene network interactions. All methods of microarray data analysis can be summarized as a study of differential gene expression. This study addresses three questions, 1) the roles of selectively expressed genes for the classification of cancer, 2) issues of accounting for both experimental and biological noise, and 3) issues …

Individual Cell Growth Rates Of Marine Bacteria, Measured By Bromodeoxyuridine Incorporation, Koji Hamasaki, Richard A. Long, Farooq Azam

Faculty Publications

We tested the application of 5-bromo-2’-deoxyuridine (BrdU), a thymidine analogue that becomes incorporated into DNA during growth, to measure growth rates of individual marine bacteria cells. Immunocytochemical detection of BrdU incorporation into bacterial DNA has the potential for single-cell-based growth measurement. Optimized procedure for immunocytochemistry was applicable to 14 marine heterotrophic bacterial isolates belonging to g-proteobacteria, α-proteobacteria, Cytophaga-Flavobacterium-Bacteroides (CFB) group and Gram-positive bacteria. The relationship between cell-specific fluorescence intensity and specific growth rate was linearly correlated among CFB group isolates, which indicated a potential of the method for quantitative measurement. Analysis of the detection limit indicated …

Uncoupling Conformational Change From Gtp Hydrolysis In A Heterotrimeric G Protein Alpha-Subunit, Celestine J. Thomas, Xinlin Du, Pilong Li, Ying Wang, Elliott M. Ross, Stephen R. Sprang

Biological Sciences Faculty Publications

Heterotrimeric G protein alpha (G alpha) subunits possess intrinsic GTPase activity that leads to functional deactivation with a rate constant of approximately 2 min(-1) at 30 degrees C. GTP hydrolysis causes conformational changes in three regions of G alpha, including Switch I and Switch II. Mutation of G202-->A in Switch II of G alpha(i1) accelerates the rates of both GTP hydrolysis and conformational change, which is measured by the loss of fluorescence from Trp-211 in Switch II. Mutation of K180-->P in Switch I increases the rate of conformational change but decreases the GTPase rate, which causes transient but …

Survey Of Anuran Populations Within Minnesota, Chris Thorman

Honors Capstones

Capstone submitted as a graduation requirement for the BSU Honors Program.

Pcr And 16s Rdna Sequencing For Identifying And Comparing Gram-Negative Bacteria, Molly Truax

Honors Capstones

Capstone submitted as a graduation requirement for the BSU Honors Program.

Passive Stretch Inhibits Central Corelike Lesion Formation In The Soleus Muscles Of Hindlimb-Suspended Unloaded Rats, D. V. Baewer, Mark A. Hoffman, Janell Romatowski, J. L. W. Bain, Robert H. Fitts, Danny A. Riley

Biological Sciences Faculty Research and Publications

Hindlimb suspension unloading (HSU) is a ground-based model simulating the effects of microgravity unloading on the musculoskeletal system. In this model, gravity causes the hind foot of the rat to drop, opening the front of the ankle to 90–105° plantar flexion at rest. As HSU proceeds, the normal weight-bearing angle of 30° dorsiflexion is achieved progressively less, and the contraction range of soleus is abbreviated. Our laboratory reported that 12 days of HSU caused central corelike lesions (CCLs) of myofibril breakdown (Riley DA, Slocum GR, Bain JL, Sedlak FR, Sowa TE, and Mellender JW. J Appl Physiol. 69: 58–66, 1990). …

Fiber Type And Temperature Dependence Of Inorganic Phosphate: Implications For Fatigue, Edward Patrick Debold, H. Dave, Robert H. Fitts

Biological Sciences Faculty Research and Publications

Elevated levels of P_i are thought to cause a substantial proportion of the loss in muscular force and power output during fatigue from intense contractile activity. However, support for this hypothesis is based, in part, on data from skinned single fibers obtained at low temperatures (≤15°C). The effect of high (30 mM) P_i concentration on the contractile function of chemically skinned single fibers was examined at both low (15°C) and high (30°C) temperatures using fibers isolated from rat soleus (type I fibers) and gastrocnemius (type II fibers) muscles. Elevating P_i from 0 to 30 mM at saturating …

Does Seed Size Affect The Rate Of Germination And Early Seedling Growth In Hairy Vetch?, Joy Ekpo

McCabe Thesis Collection

Size is an important characteristic of seed quality because larger seeds with larger volume contain more resources and are likely to exhibit greater vigor than smaller seeds (Ellis, 1992). In a range of plant species, seed size has been shown to affect germination rate, emergence rate, success of establishment, and growth (Black 1957; Bentley et al. 1980; Sanderson et al. 2002). Hairy vetch is an annual legume that is used for improvement of soil for pasture and to provide ground cover protecting against erosion (Duke 1981; Undersander 2002; Sattell et al 1988). Problems facing the establishment of hairy vetch are …

Genetic Analysis Of The Putative Streptolysin O Regulator From Streptococcus Pyogenes, Robert Tyrone Billingslea

McCabe Thesis Collection

Group A streptococci (Streptococcus pyogenes) is one of the most frequent pathogens of humans. It is estimated that between 5-15% of normal individuals harbor the bacterium, usually in the upper respiratory tract, without signs of disease. S. pyogenes can initiate an active infection when defenses are compromised or when the organism is able to penetrate the host's defenses. When the bacteria invade vulnerable tissues, a variety of suppurative infections can occur. Acute S. pyogenes infection may be present as pharyngitis ("strep throat"), scarlet fever (rash), impetigo (infection of the superficial layers of the skin) or cellulitis (infection of the deep …

Moisture Potential Affects Rate Of Leaf Appearance In Cool Season Grasses, Nina Cherone Terrell

McCabe Thesis Collection

The rate of leaf appearance and onset of growth in cool season grasses may be influenced by soil moisture potential and exposure to below freezing temperatures. Levels of moisture potential and days exposed to freezing temperatures, which will restrict leaf appearance, are not well defined. The first part of this study was to determine the effects of different moisture potentials on the leaf appearance rates in two cool season grasses. Italian ryegrass (IRG) and tall wheat grass (TWG) were grown hydroponically at 4 moisture potentials in seed pouches in an incubator under a photoperiod of 13 hours light and 11 …

Antimicrobial Activities Of Lipodepsipeptide Syringopeptins, Mekki F. Bensaci

Biology

Many strains of the plant bacterium Pseudomonas syringae produce two major classes of cyclic lipodepsipeptides, the syringomycins and the syringopeptins. Four groups of small cyclic lipodepsipeptides are well known: the syringomycins, syringostatins, syringotoxins, and pseudomycins. They all have antimicrobial activities and tend to be more active against yeasts than against bacteria. The syringopeptins are lesser-known. The best-studied syringopeptins are SP22 and SP25. They possess antibacterial and antifungal activities, but their mechanisms of action and antimicrobial spectra are less studied. Saccharomyces cerevisiae sphingolipid and sterol biosynthetic mutants were used to investigate the mechanism of action of syringopeptins against fungi. Similarly to …

Rapid Evolution Of An Invasive Plant, John L. Maron, Montserrat Vilà, Riccardo Bommarco, Sarah Elmendorf, Paul Beardsley

Biological Sciences Faculty Publications

Exotic plants often face different conditions from those experienced where they are native. The general issue of how exotics respond to unfamiliar environments within their new range is not well understood. Phenotypic plasticity has historically been seen as the primary mechanism enabling exotics to colonize large, environmentally diverse areas. However, new work indicates that exotics can evolve quickly, suggesting that contemporary evolution may be more important in invasion ecology than previously appreciated. To determine the influence of contemporary evolution, phenotypic plasticity, and founder effects in affecting phenotypic variation among introduced plants, we compared the size, fecundity, and leaf area of …

Role Of Hydrophobic Residues In The Central Ectodomain Of Gp41 In Maintaining The Association Between Human Immunodeficiency Virus Type 1 Envelope Glycoprotein Subunits Gp120 And Gp41, Joanne York, Jack H. Nunberg

Biological Sciences Faculty Publications

The interaction between the gp120 and gp41 subunits of the human immunodeficiency virus envelope glycoprotein serves to stabilize the virion form of the complex and to transmit receptor-induced conformational changes in gp120 to trigger the membrane fusion activity of gp41. In this study, we used site-directed mutagenesis to identify amino acid residues in the central ectodomain of gp41 that contribute to the stability of the gp120-gp41 association. We identified alanine mutations at six positions, including four tryptophan residues, which result in mutant envelope glycoprotein complexes that fail to retain gp120 on the cell surface. These envelope glycoproteins readily shed their …

Amebiasis And Comparison Of Microscopy To Elisa Technique In Detection Of Entamoeba Histolytica And Entamoeba Dispar, Clarence Lee

Department of Biology Faculty Publications

The analysis of records of amoebal infection in various hospitals in Kilimanjaro indicated frequent occurrence of amebiasis. The population over the age of five years had higher rate of amoebal infection compared to less than that of a five-year-old population; however, both age groups had similar patterns of amebiasis during January 1999 to June 2001. To investigate misdiagnosis of amebiasis, 226 patients (passive cases) in three hospitals and 616 individuals (active cases) from three different localities in Kilimanjaro were examined. In passive cases, the prevalences of Entamoeba histolytica and Entamoeba dispar were 1% and 7.3%, respectively. Among active cases, 1% …

Investigation Into The Spatial And Temporal Dynamics Of Stomatal Networks To Determine Whether Plants Perform Emergent, Distributed Computation, Jevin West

Biology

This research studies the spatial and temporal dynamics of stomatal patchiness in order to investigate the possibility that plants solve their problem of adjusting stomatal aperture in order to maximize CO₂ uptake while minimizing H₂O loss through an emergent, distributed computation. An extensive study is done on qualitative and quantitative characteristics of stomatal patchiness, and improved imaging techniques are developed to more fully capture the dynamics. In doing so, soliton-like structures were discovered. Sequences of chlorophyll fluorescence images of Xanthium strumarium leaves were then compared to image sequences of cellular computer simulations that solve problems via emergent, …

Analysis Of Phosphatidylinositol 4,5-Biphosphate And Inositol 1,4,5-Triphosphate In Dehydration And Cold-Stressed Arabidopsis Thaliana, James E. Thompson

Biology

During dehydration and cold stress, Arabidopsis thaliana (A. thaliana) plant cells mobilize calcium into their cytosol to elicit changes in gene expression that enable them to tolerate stress. It has been unclear how dehydration-stressed plant cells receive and transmit the signal that results in promoting increases in intracellular calcium concentration. Previously, phosphatidylinositol 4,5-biphosphate (PtdIns(4,5)P₂) and inositol 1,4,5 triphosphate (Ins(1,4,5)P₃) have been shown to accumulate and cause calcium mobilization in osmotically stressed A. thaliana. However, it was unknown whether the same occurred in plants exposed to other abiotic stresses. Data presented in this thesis …

Stoichiometric And Environmental Controls Of Consumer-Driven Nutrient Recycling In Steams, John D. Rothlisberger

Biology

I investigated the environmental control of consumer-mediated nutrient recycling (CNR) in sub-alpine streams by evaluating the effects of water temperature and food elemental composition on the rates and ratios of nitrogen (N) and phosphorus (P) excretion by macroinvertebrates. I predicted that biomass-specific excretion rates would be positively correlated with temperature whereas N:P ratios would primarily relate to food N:P ratio. I measured nutrient release by heptagenaiid larvae eating periphyton of varying elemental composition grown on nutrient-diffusing substrates. I hypothesized that skewed ratios of N:P release would result from differential retention of nutrients in the food. Excretion rates of N and …

Studies Of Saccharomyces Cerevisiae Sphingolipid C4 Hydroxylation And Ipt1 Function And Their Roles In Syringomycin E Action, Jolanta Idkowiak-Baldys

Biology

Sphingolipids are ubiquitous membrane components of all eukaryotic cells with important regulatory functions. The roles and biochemistry of two structural features of sphingolipids were studied: C4 hydroxylation and the addition of a terminal phosphoinositol. Structure-function studies of the yeast sphingolipid C4 long chain base hydroxylase (Sur2p) revealed that alanine replacement of any of eight histidine residues from three histidine-rich motifs, as well as additional histidine 249, eliminated hydroxylase activity. Seven additional residues were also found to be important elements of the active site. These results show that Sur2p is a member of the family of eight-histidine motif hydroxylases and desaturates. …

Dynamics Of Pectoral Fin Rowing In A Fish With An Extreme Rowing Stroke: The Threespine Stickleback (Gasterosteus Aculeatus), Jeffrey A. Walker Phd

Faculty Publications

The dynamics of pectoral fin rowing in the threespine stickleback are investigated by measuring the instantaneous force balance on freely swimming fish throughout the stroke cycle and comparing the measured forces with fin motions and an unsteady, blade-element model of pectoral fin propulsion. Both measured and modeled forces suggest that attached vortex and circulatory forces and not inertial (added mass) forces dominate the force balance. Peak forces occur at midstrokes. There is no evidence for large force peaks at the stroke transitions due to either rapid fin rotation (supination) or rapid fin closure against the body. The energetics of pectoral …

Isolation And Characterization Of T-Dna Insertional Mutations In Arabidopsis Thaliana And Its Use In Determining Siamese, Taylor S. Gwin

Honors Capstones

No abstract provided.

Population Size And Movements Of Spotted Salamanders At South Holston Dam, Sullivan County, Tennessee., Eric Alexander Smith

Electronic Theses and Dissertations

In the Southern Appalachians, there are growing concerns about Spotted Salamanders (Ambystoma maculatum) due to habitat destruction and the uncertain future of their forested riparian habitat. In this study, I establish baseline data of a population of Spotted Salamanders so future monitoring of this population can be performed. The study site is located in northeastern Tennessee, just east of the city of Bristol. It is a vernal pond at the Osceola Island Recreation Area one mile below the South Holston Dam on Holston View Dam road. A drift fence was established completely around the perimeter of the vernal …

Similarity Of Mammalian Body Size Across The Taxonomic Hierarchy And Across Space And Time, Felisa A. Smith, James H. Brown, John P. Haskell, S. Kathleen Lyons, John Alroy, Eric L. Charnov, Tamar Dayan, Brian J. Enquist, S.K. Morgan Ernest, Elizabeth A. Hadly, David Jablonski, Kate E. Jones, Dawn M. Kaufman, Pablo A. Marquet, Brian A. Maurer, Karl J. Niklas, Warren P. Porter, Kaustuv Roy, Bruce Tiffney, Michael R. Willig

Biology Faculty & Staff Publications

Although it is commonly assumed that closely related animals are similar in body size, the degree of similarity has not been examined across the taxonomic hierarchy. Moreover, little is known about the variation or consistency of body size patterns across geographic space or evolutionary time. Here, we draw from a data set of terrestrial, nonvolant mammals to quantify and compare patterns across the body size spectrum, the taxonomic hierarchy, continental space, and evolutionary time. We employ a variety of statistical techniques including "sib-sib" regression, phylogenetic autocorrelation, and nested ANOVA. We find an extremely high resemblance (heritability) of size among congeneric …

Rare, Threatened And Endangered Species Of Oregon (2004), James S. Kagan, Sue Vrilakas, Eleanor P. Gaines, Cliff Alton, Fern Mcarthur, Kuuipo Walsh, Eric Scheuering, John A. Christy, Jon Hak, Claudine Tobalske, Annie Weiland, Theresa Koloszar, Oregon Natural Heritage Information Center

Institute for Natural Resources Publications

Extinction is a natural process. Today, however, plant and animal species are disappearing world-wide at an accelerated pace. Based on current trends, half of the species on earth will be extinct within the next 100 years. The major cause of this phenomenon is large-scale destruction of native habitats, which has increased since European settlement began in the mid 1800's - in Oregon and throughout the New World.

Once lost, a species can never be recovered, and there is no way of knowing how useful it may have been. We do know that human beings and many of their industries depend …

Community Ecology Of Freshwater, Brackish And Salt Marshes Of The Rio Grande Delta, Frank W. Judd, Robert I. Lonard

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Species composition and importance, species diversity and evenness, species richness, and community similarity are compared among 6 freshwater, 9 brackish and 11 salt marshes in the Rio Grande Delta. Community similarity is generally low among marshes, but salt marshes have a greater mean coefficient of similarity than brackish marshes. Species richness per marsh ranges from 15 to 31 for freshwater marshes, 7 to 24 for brackish marshes and 7 to 26 for salt marshes. Each freshwater marsh has a different dominant species. The first six species in importance in all three kinds of marshes contribute from 72.6 to 99.8% of …

Alkaloids And Old Lace: Pollen Toxins Exclude Generalist Pollinators From Death Camas, Melissa Weber

Undergraduate Honors Capstone Projects

Many plants produce toxins to which specialist herbivores - typically insects - have evolved counter-adaptations, sometimes resulting in a co-evolutionary arms race. Although many non-social bee species are likewise taxonomic host specialists, the pollination guilds at their floral hosts frequently include diverse floral generalists as well, even on plants that are otherwise chemically defended. In this study, we show that pollen and nectar of foothills death camas (Toxicoscordion [=Zigadenus] paniculatum) contains zygacine, the alkaloid responsible for this plant's notorious mammalian toxicity. Many adults and larvae of the generalist solitary bee, Osmia lignaria (Megachilidae), were paralyzed and …

Snow Avalanche Disturbance In Intermountain Spruce-Fir Forests And Implications For The Spruce Bark Beetle (Coleoptera: Scolytidae), Elizabeth G. Herbertson

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Spruce beetle outbreaks are the primary biotic disturbance affecting forests in the Intermountain spruce-fir zone. Major snow avalanches can produce large quantities of host material for spruce beetle colonization; however, few studies have examined the influence of avalanche disturbance on outbreak initiation. The purpose of my research was to investigate potential relationships between these two disturbance agents. In the first study, I used dendro-ecological analyses to date major avalanche years on the Wasatch Plateau in south-central Utah, and then determined what climate factors were associated with avalanche occurrence. The results indicated that mean January snowfall was significantly related to the …