Digital Commons Network^™

Scientific Investigation Of The Plant Pathogen Agrobacterium Tumefaciens, Casey M. Flanagan, Christopher B. Crowell Ii, Bryan P. Markelz

Honors Theses

A. tumefaciensis a plant pathogen and causative agent of Crown Gall Disease, an ailment that results in the development of tumors in plants. It is a unique organism in that it is the only known non-viral pathogen that transfers its DNA into the host cell. Consequently, the majority of the research conducted on A. tumefaciensinvestigates its mechanism of infection. However, A. tumefaciensis also rare to the bacterial world in that its genome is comprised of two chromosomes: one circular and one linear. Most other bacteria only have one circular chromosome. This area of research has been grossly overlooked and therefore …

Distributions And Possible Roles Of Laminin, Fibronectin And Theirreceptor Subunits Integrin \Beta4 And \Alpha5 In Remodelling Of Extracellularmatrix During Decidualization In Rats, Ümi̇t Ali̇ Kayişli, Mevlüt Asar, Ramazan Demi̇r

Turkish Journal of Biology

In the endometrium preparing for pregnancy, the stromal matrix components of the cells and their products begin structural differentiation due to endometrial receptivity. According to the hypothesis that 'extracellular matrix (ECM) proteins and adhesion molecules take roles in the structural differentiation as a result of endometrial decidualization', our aim was to determine the roles of ECM molecules laminin, fibronectin and adhesion proteins integrin \alpha5 and \beta4 in the decidulization and implantation by examining the emergence and changing distribution of these proteins. In this study, five experimental groups, consisting of 40 pregnant animals on pregnancy days 4-8, were used. Paraffin tissue …

The Possibility Of Using Crustacean Waste Products(Cwp) On Rainbow Trout ( Oncorhynchus Mykiss)Feeding, Yeşi̇m Özoğul

Turkish Journal of Biology

Crustacean waste product (CWP) generated from the fishing industry could be used in diets for rainbow trout as an alternative animal protein. Some experiments have been undertaken with penaid species, showing that it is possible to partially replace fish meal with CWP in penaid feeds. This study has been designed to assess whether CWP could be used to partially replace fish meal in diets for rainbow trout. The results show that CWP improved the digestibility of the diet, yielding the highest performance, and also that the addition of large amounts of CWP to a low-protein diet did not depress appetite. …

Effect Of Spaceflight On The Maximal Shortening Velocity, Morphology, And Enzyme Profile Of Fast- And Slow-Twitch Skeletal Muscle Fibers In Rhesus Monkeys, Robert H. Fitts, Janell Romatowski, Lourdes De La Cruz, Jeffrey J. Widrick, Dominique Desplanches

Biological Sciences Faculty Research and Publications

No abstract provided.

Characterizing The Role Of Mapk Phosphates In Plants, Laura Asakura

Honors Theses

Mitogen Activated Protein Kinase (MAPK) pathways e ubiquitous ongst eukaryotes, involved in the signal transduction of various external stimuli to the nucleus. In plants, only MAPK pathways related to pathogen- and stress-related responses have been identified. It has been proposed that another MAPK pathway exists in plants, one that is similar to animal MAPK pathways and postulated to connect the regulation of cell growth and the actions of hormones auxin, cytokinin, and gibberellin. In order to establish whether a link exists between the MAPK pathway and hormone signaling in plants, the role of MAPK phosphatases (MKP) on hormone signaling was …

Phenotypic Effects Of Leptin In An Ectotherm: A New Tool To Study The Evolution Of Life Histories And Endothermy?, Peter H. Niewiarowski

Biology Faculty Research

Leptin is a hormone that regulates energy expenditure and body mass in mammals, and it has attracted considerable attention because of its potential in treating human obesity. Comprehensive data from both pathological and non-pathological systems strongly support a role for leptin in regulating energy metabolism, in thermoregulation and in regulating the onset of puberty. We report here that daily injections of recombinant murine leptin in fence lizards (Sceloporus undulatus) produce phenotypic effects similar to those observed when leptin injections are given to mice, Lizards injected with leptin had body temperatures 0.6 degrees C higher, ate 30 % less food and …

Respiration And Heart Rate At The Surface Between Dives In Northern Elephant Seals, Burney J. Le Boeuf, Daniel E. E. Crocker, Jason Gedamke, J. Grayson, Paul M. Webb, Susanna B. Blackwell, Daniel P. Costa

Arts & Sciences Faculty Publications

All underwater activities of diving mammals are constrained by the need for surface gas exchange. Our aim was to measure respiratory rate (fb) and heart rate (fh) at the surface between dives in free-ranging northern elephant seals Mirounga angustirostris. We recorded fb and fh acoustically in six translocated juveniles, 1.8-2. 4 years old, and three migrating adult males from the rookery at Ano Nuevo, California, USA. To each seal, we attached a diving instrument to record the diving pattern, a satellite tag to track movements and location, a digital audio tape recorder or acoustic datalogger with an external hydrophone to …

Plant Quality And Spider Predation Affects Grasshoppers (Acrididae): Food-Quality-Dependent Compensatory Mortality, Mark A. Oedekoven, Anthony Joern

School of Biological Sciences: Faculty Publications

For insect herbivores, population responses reflect interactions among multiple factors, including abiotic conditions, food plant availability, and biotic interactions guided by food limitation and natural enemies. In this set of field experiments, we evaluated the interactive, dynamic effects of limited food supply and predation from wolf spiders (Lycosidae) on mortality in Ageneotettix deorum, a common grasshopper (Acrididae) from North American sandhills grasslands. We attempted to determine whether the combined effects of food availability and spider predation on mortality were (1) noncompensatory, with the effects of each factor summing to determine ultimate population size, or (2) compensatory, where the effect …

Mechanisms Of Convergence And Extension By Cell Intercalation, Maxellende Ezin

Biology Faculty Works

The cells of many embryonic tissues actively narrow in one dimension (convergence) and lengthen in the perpendicular dimension (extension). Convergence and extension are ubiquitous and important tissue movements in metazoan morphogenesis. In vertebrates, the dorsal axial and paraxial mesodermal tissues, the notochordal and somitic mesoderm, converge and extend. In amphibians as well as a number of other organisms where these movements appear, they occur by mediolateral cell intercalation, the rearrangement of cells along the mediolateral axis to produce an array that is narrower in this axis and longer in the anteroposterior axis. In amphibians, mesodermal cell intercalation is driven by …

Direct And Indirect Effects Of Herbivores On Nitrogen Dynamics: Voles In Riparian Areas, J M. Sirotnak, Nancy J. Huntly

Biology Faculty Publications

Herbivores can directly increase nitrogen mobility by increasing the quality of organic matter entering the decomposition cycle, but they also may decrease nitrogen mobility by decreasing the biomass of high-nitrogen species in the plant community. We assessed effects of voles (Microtus) on nitrogen dynamics using exclosures in two riparian meadows (Crystal Bench and Blacktail Deer Creek) in Yellowstone National Park (USA). At both sites, the quantity of plant litter was decreased by herbivory following a vole population peak in 1992. At Crystal Bench, removal of voles caused a decrease in the nitrogen concentration and an increase in the C:N ratio …

First Nesting Record Of Blue Jay (Cyanocitta Cristata) In Hidalgo County, Texas, Timothy Brush

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

No abstract provided.

Effects Of Age And Group Size On Habitat Selection And Activity Level In Xenopus Laevis Tadpoles, D. R. Golden, Geoffrey R. Smith, Jessica E. Rettig

Faculty Publications

No abstract provided.

Studying The Expression Of A Novel Microsatellite Mrna In Chironomous Riparius, Mina Ranzurmal

Seton Hall University Dissertations and Theses (ETDs)

The expression of a unique mRNA containing a microsatellite sequence was studied in C. riparius using differential display. First, the rnicrosatellite fragment was sequenced using Sanger's Sequencing method. The microsatellite cDNA contained 11 "ACA" repeats, 12 "AC" repeats, and 5 "CTC" repeats. Second, the affects of cadmium and heat shock on rnicrosatellite mRNA expression were studied. In cadmium experiments, larvae were exposed to low cadmium concentrations (0, 0.04, 0.4, and 4.0 mM) for 24 and 48 h and high cadmium concentrations (0, 1.0, 2.0, 4.0, 8.0, and 16.0 mM) for 48 h. The effects of cadmium on fed larvae at …

Detoxification Of 4-Nitroquinoline 1-Oxide And Benzo(A)Pyrene-4,5-Oxide By Myristicin Induced Glutathione S-Transferase In A/J Mouse Livers, Eduardo Saldivar

Theses and Dissertations - UTB/UTPA

The activities of mouse liver glutathione S-transferases (GSTs) induced by myristicin, the active compound in parsley leaf oil, against the carcinogens 4-nitroquinoline 1-oxide (4NQO) and benzo(a)pyrene-4,5-oxide (BP-4,5-oxide) were studied. A/J mice were treated with three 20 mg doses (one dose every other day) by gavage. Affinity purified liver GST samples from treated animals showed a 7.2-fold increase in activity toward 4NQO when compared with equal amounts of liver samples prepared from the control group. Activity against BP-4,5-oxide was increased 1.8-fold in the experimental group. Experimental samples also showed a significant increase in activity toward the substrates 1-chloro-2,4-dinitrobenzene (CDNB), 2,4-dichloronitrobenzene (DCNB), …

Use Of Oak Hammocks By Neotropical Migrant Songbirds During Stopover In Coastal South Carolina, Scott Glen Somershoe

College of Graduate Studies: Theses & Dissertations (1964–2006)

Many species of Neotropical migrant songbirds have been reported to be declining in the last few decades, and the loss and fragmentation of stopover habitat has been implicated as a potential cause of these population declines. To manage properly a fragmented forest landscape for migrating songbirds information is needed on how the size and the habitat of forest fragments influence their use by migrants during stopover. Therefore, I conducted censuses of Neotropical migrant birds in eight oak hammocks of varying size (0.32-3.08 ha) at the Savannah National Wildlife Refuge, Jasper County, South Carolina. Censuses were conducted at 0600-1030 h during …

The Abundance And Distribution Of Arthropods From Sandstone Outcrops In Coffee County, Georgia, F. Michael Mcaloon

College of Graduate Studies: Theses & Dissertations (1964–2006)

Broxton Rocks Nature Preserve, a 1,233-hectare preserve containing late Pleistocene sandstone (Altamaha grit) outcrops of various sizes and topographies in a conifer-dominated loblolly pine - hardwood forest, represents a unique habitat to the coastal plain of Georgia. Using modified pitfall traps, I sampled arthropods in four subhabitats (bare rock, lichens, ecotone, wiregrass) at Broxton Rocks between January and November 1999. A total of 312,006 arthropods belonging to four classes (Arachnida, Diplopoda, Chilopoda, Insecta) represented by 24 orders was trapped. The numbers of arthropods varied among habitat types, and over the collection dates (P

The Effects Of Low Ph On Sunfish Assemblages In Southeast Georgia, William Boyd Tate

College of Graduate Studies: Theses & Dissertations (1964–2006)

No abstract provided.

Effects Of Height And Vegetation On Success Of Bird Nests In Maritime Forests, Sharon M. Defalco

College of Graduate Studies: Theses & Dissertations (1964–2006)

Nest predation is an important source of mortality in songbirds and may contribute to declines in Neotropical migrants. I used artificial nests baited with fresh Japanese Quail and Zebra Finch eggs in conjunction with observations of natural nests to quantity the ettects ol nest height and vegetation on nest predation on St. Catherine's Island, a barrier island in southeast Georgia. Because of intense browsing by white-tailed deer. I predicted that lower, more exposed nests would be least successful. Artificial nests (n = 389) were placed in the field, and natural nests (n = 49) were observed, durintz April and May …

Identification Of Potential Molecular Biomarkers Of Cadmium Induced Stress In C̲Hironomus Tentans ̲, David Hunter Dyer

Dissertations and Theses @ UNI

The objective of this research was to identify potential molecular biomarkers by looking for differences in the mRNA expression patterns between cadmium exposed and non-exposed freshwater aquatic invertebrate larvae. In the future, genes that indicate sublethal damage to a population at risk could be used to monitor the degradation or regeneration of an ecosystem. For this study, laboratory reared Chironomus tentans were placed in a sublethal concentration of cadmium treated water and the genes turned on in response to the cadmium were isolated from a cDNA subtract library. Six genes were identified and two potential biomarkers of environmental stress, ferritin …

Structure And Function Analysis Of Lin-14, A Temporal Regulator Of Postembryonic Developmental Events In Caenorhabditis Elegans, Yang Hong, Rosalind C. Lee, Victor Ambros

Dartmouth Scholarship

During postembryonic development of Caenorhabditis elegans, the heterochronic gene lin-14 controls the timing of developmental events in diverse cell types. Three alternativelin-14 transcripts are predicted to encode isoforms of a novel nuclear protein that differ in their amino-terminal domains. In this paper, we report that the alternative amino-terminal domains of LIN-14 are dispensable and that a carboxy-terminal region within exons 9 to 13 is necessary and sufficient for in vivo LIN-14 function. A transgene capable of expressing only one of the three alternativelin-14 gene products rescues a lin-14 null mutation and is developmentally regulated by lin-4. …

Late Quaternary Fossil Mammals And Last Occurrence Dates From Caves At Barahona, Puerto Rico, Donald A. Mcfarlane

WM Keck Science Faculty Papers

Puerto Rico supported at least five genera of endemic terrestrial mammals in the late Quaternary, all of which are extinct. Whether these animals died out in the late Pleistocene, the mid-Holocene, or in post-Columbian time has not been established. This paper is the first attempt at radiometrically dating the 'last occurrences' of these taxa, together with the first unambiguous descriptions of localities reported by previous workers. Last occurrence dates for Nesophontes, Elasmodontomys and Heteropsomys are shown to be mid-Holocene and overlap with Amerindian occupation of the island. Acratocnus is known only from the late Pleistocene. No Puerto Rican taxon has …

Abalone Aquaculture In Western Australia : Policy Guideline., Fisheries Western Australia.

Fisheries Management Papers

Experimental or commercial abalone aquaculture is being pursued in many countries with major investments in The United States, Taiwan, China and Korea as well as in Australia. The combined total abalone aquaculture production from China and Taiwan was reported to be in the order of 2,000 tonnes and continues to rise. As cultured ‘cocktail’ abalone are below the legal harvest size of wild abalone, there will be limited competition between aquaculture and the wild fisheries.

Monogenic Control Of Iris Coloration In The January Tetra (Hemigrammus Hyanuary Characidae), Jack Frankel

Department of Biology Faculty Publications

The January tetra (Hemigrammus hyanuary Durbin) exhibits two eye color phenotypes. These have a silver iris, which is characteristic of the species, and a green color variant. Segregation patterns observed in the progenies from 12 different crosses support an hypothesis for the monogenic inheritance of iris coloration in this species.

Black-Tailed Deer Habitat Changes In A Portion Of The Mount St. Helens Blast Zone, Ronald W. Davis

All-Inclusive List of Electronic Theses and Dissertations

This study utilized Landsat TM imagery to evaluate black-tailed deer habitat changes in a portion of the Mount Saint Helens blast zone in western Washington. The purpose of this study was to compare the post eruption vegetation changes with population trends for black tailed deer. The 55,000-acre study area comprises a Washington Department of Game Management unit (GMU 524) located to the northnorthwest of Mount St. Helens. Approximately 80% ofthe mostly forested study area was affected by lateral blast from the 1980 eruption. The area is predominantly private land managed for timber production but a small portion falls within the …

Use Of Randomly Amplified Polymorphic Dna-Polymerase Chain Reaction (Rapd-Pcr) To Distinguish North American Populations Of Acroptilon Repens (L.) Dc, Raul A. Ruiz

Theses and Dissertations - UTB/UTPA

Sixty U.S. populations of Acroptilon repens collected in 1998 were analyzed using RAPD-PCR. Each population was represented by five specimens gathered from each location. A total of 301 specimens were examined using two Operon Technologies, RAPD-PCR primers (A 10 and C04). The DNA amplification products produced through the PCR process were electrophoretically separated to produce DNA fragments ranging from 100 to 2000 base-pairs in length. The 60 U.S. populations sampled, produce ten RAPD banding pattern types using A 10 primer and seventeen pattern types with C04. Genetic variation within and among the populations was low, however, one dendogram did show …

The Return Of The Wild, John Jahoda

Bridgewater Review

No abstract provided.

Phylogeography Of The Night Lizard, Xantusia Henshawi, From Southern California, Robert Edward Lovich

Loma Linda University Electronic Theses, Dissertations & Projects

The granite night lizard, Xantusia henshawi, is a highly specialized crevice dwelling lizard found in the Peninsular Ranges of southern California, United States and northern Baja California, Mexico. Generally, little morphological variation is seen in this species over a variety of habitats throughout its range, from elevations near sea level to approximately 2000 meters, and from Mediterranean habitats near the Pacific coast to arid desert habitat in the Colorado Desert of California. One exception is the variation seen in the subspecies X h. gracilis, which differs from X h. henshawi in morphology, allozymes, ecology, and natural history.

In …

Evolutionary And Acclimation-Induced Variation In The Heat-Shock Responses Of Congeneric Marine Snails (Genus Tegula) From Different Thermal Habitats: Implications For Limits Of Thermotolerance And Biogeography, Lars Tomanek, George N. Somero

Biological Sciences

Heat stress sufficient to cause cellular damage triggers the heat-shock response, the enhanced expression of a group of molecular chaperones called heat-shock proteins (hsps). We compared the heat-shock responses of four species of marine snails of the genus Tegula that occupy thermal niches differing in absolute temperature and range of temperature. We examined the effects of short-term heat stress and thermal acclimation on the synthesis of hsps of size classes 90, 77, 70 and 38 kDa by measuring incorporation of (35)S-labeled methionine and cysteine into newly synthesized proteins in gill tissue. Temperatures at which enhanced synthesis of hsps first occurred …

Allometric Scaling Of Production And Life-History Variation In Vascular Plants, Brian Enquist, Geoffrey West, Eric Charnov, James Brown

Biology Faculty & Staff Publications

A prominent feature of comparative life histories is the well documented negative correlation between growth rate and life span. Patterns of resource allocation during growth and reproduction reflect life-history differences between species. This is particularly striking in tropical forests, where tree species can differ greatly in their rates of growth and ages of maturity but still attain similar canopy sizes. Here we provide a theoretical framework for relating life-history variables to rates of production, dM/ dt, where M is above-ground mass and t is time. As metabolic rate limits production as an individual grows, dM=dt ~M3=4. Incorporating interspecific variation in …

The Kinesin-Related Protein, Hset, Opposes The Activity Of Eg5 And Cross-Links Microtubules In The Mammalian Mitotic Spindle, Vicki Mountain, Calvin Simerly, Louisa Howard, Asako Ando, Gerald Schatten, Duane A. Compton

Dartmouth Scholarship

We have prepared antibodies specific for HSET, the human homologue of the KAR3 family of minus end-directed motors. Immuno-EM with these antibodies indicates that HSET frequently localizes between microtubules within the mammalian metaphase spindle consistent with a microtubule cross-linking function. Microinjection experiments show that HSET activity is essential for meiotic spindle organization in murine oocytes and taxol-induced aster assembly in cultured cells. However, inhibition of HSET did not affect mitotic spindle architecture or function in cultured cells, indicating that centrosomes mask the role of HSET during mitosis. We also show that (acentrosomal) microtubule asters fail to assemble in vitro without …