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Finfish Aquaculture In Western Australia. Final Esd Management Report For Marine Finfish Aquaculture., Department Of Fisheries Western Australia. Jun 2009

Finfish Aquaculture In Western Australia. Final Esd Management Report For Marine Finfish Aquaculture., Department Of Fisheries Western Australia.

Fisheries Management Papers

It has been recognized that there are a number of potential impediments to achieving continued growth of this industry. These include the need for increased investment, an expansion in markets and ensuring environmental sustainability. One of the most important however, is meeting the growing expectations of the community that all aquaculture sectors can clearly demonstrate that they are operating within the principles of Ecologically Sustainable Development (ESD). Western Australia’s Department of Fisheries is responsible for the management of aquaculture in the State and is committed to implementing ESD. These principles are contained within the objectives of the Fish Resources Management …

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Investigating The Roles Of Ndj1 And Tid1 In Distributive Segregation Using Non-Exchange Chromosomes, Jonathan V. Henzel Jun 2009

Investigating The Roles Of Ndj1 And Tid1 In Distributive Segregation Using Non-Exchange Chromosomes, Jonathan V. Henzel

Master's Theses

Meiosis is a specialized cell division that leads to a reduction of ploidy in sexually reproducing organisms through segregation of homologous chromosomes at the first meiotic division. Improper segregation of chromosomes during meiosis results in anueploidy, which is usually fatal during embryonic development. The meiotic process is therefore tightly regulated. Typically, proper segregation of homologs at meiosis I requires pairing of homologous chromosomes, followed by crossover recombination between homologs. Crossovers enable proper chromosomal segregation during the first meiotic division in part by establishing tension in the meiotic spindle. However, in the absence of crossovers, some cells maintain the ability to …

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The Relationship Between Plasma Steroid Hormone Concentrations And The Reproductive Cycle Of The Northern Pacific Rattlesnake, Crotalus Oreganus, Craig Michael Lind Jun 2009

The Relationship Between Plasma Steroid Hormone Concentrations And The Reproductive Cycle Of The Northern Pacific Rattlesnake, Crotalus Oreganus, Craig Michael Lind

Master's Theses

To gain a better understanding of the role of steroid hormones in vertebrate reproduction, we quantified steroid hormone concentrations in a free ranging population of the Northern Pacific rattlesnake, Crotalus oreganus. Plasma steroid hormone concentrations were quantified for both male and female snakes throughout the active season (Mar-Oct). We measured testosterone (T), 5α-dihydrotestosterone (DHT), and corticosterone (B) concentrations in male and female snakes. 17β-estradiol (E2) and progesterone (P) were measured in females only. We also observed breeding behaviors (e.g. consortship, courtship, and copulation) in the field and measured testis and follicle size in male and female snakes from museum collections. …

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Fisheries Occasional Publication No. 68 - A Quota Management System For The Western Rock Lobster Fishery, Rock Lobster Industry Advisory Committee (Rliac), Department Of Fisheries, Western Australia Jun 2009

Fisheries Occasional Publication No. 68 - A Quota Management System For The Western Rock Lobster Fishery, Rock Lobster Industry Advisory Committee (Rliac), Department Of Fisheries, Western Australia

Fisheries Occasional Publications

There has been much debate over the past two decades on the most appropriate long-term management framework for Western Australia’s Western Rock Lobster Fishery. More recently a debate over whether the fishery would be best managed under a Quota Management System (QMS) or the continuation of the current Input Control Management System (ICMS) culminated in an industry vote coordinated by the Western Rock Lobster Council (WRLC) in 2006 . The outcome of this vote resulted in industry support to retain the existing management system based on input controls2 , however, shortly after the vote there was a renewed level of …

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Fisheries Occasional Publication No. 69 - An Input Control Management System For The Western Rock Lobster Fishery, Rock Lobster Industry Advisory Committee (Rliac), Department Of Fisheries Western Australia Jun 2009

Fisheries Occasional Publication No. 69 - An Input Control Management System For The Western Rock Lobster Fishery, Rock Lobster Industry Advisory Committee (Rliac), Department Of Fisheries Western Australia

Fisheries Occasional Publications

The Rock Lobster Industry Advisory Committee (RLIAC), the Hon. Minister for Fisheries and the Department of Fisheries, Western Australia have commenced a process of assessing the options for future management of the Western Rock Lobster Fishery. As part of this assessment, an expert Panel has previously prepared an analysis of an optimal quota management system (QMS) suitable for the fishery. As the next step in the assessment of management options, RLIAC requested that an expert panel also advise them on the design characteristics of an improved input control management system (ICMS) for the fishery and to provide advice on the …

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Alternative Life Cycle Strategies And Colonization Of Young Anurans By Gorgoderina Attenuata In Nebraska, Matthew G. Bolek, Scott D. Snyder, John J. Janovy Jr. Jun 2009

Alternative Life Cycle Strategies And Colonization Of Young Anurans By Gorgoderina Attenuata In Nebraska, Matthew G. Bolek, Scott D. Snyder, John J. Janovy Jr.

Biology Faculty Publications

Studies on life cycles and epizootiology of North American frog bladder flukes indicate that adult frogs become infected predominantly by ingesting tadpoles or other frogs that serve as second intermediate hosts for gorgoderid metacercariae. Other studies have indicated that newly metamorphosed frogs are rarely infected with these parasites because they are gape-limited predators that cannot feed on large intermediate hosts such as tadpoles and other frogs. We examined the role of potential intermediate hosts in the recruitment of the frog bladder fluke, Gorgoderina attenuata, to metamorphosed northern leopard frogs, Woodhouse’s toads, and bullfrogs from western Nebraska. We completed the …

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Unlocking The Secrets Of The Genome, Susan Celniker, Laura Dillon, Mark Gerstein, Kristin Gunsalus, Steven Henikoff, Gary Karpen, Manolis Kellis, Eric Lai, Jason Lieb, David Macalpine, Gos Micklem, Fabio Piano, Michael Snyder, Lincoln Stein, Kevin White, Robert Waterston, Sarah C.R. Elgin Jun 2009

Unlocking The Secrets Of The Genome, Susan Celniker, Laura Dillon, Mark Gerstein, Kristin Gunsalus, Steven Henikoff, Gary Karpen, Manolis Kellis, Eric Lai, Jason Lieb, David Macalpine, Gos Micklem, Fabio Piano, Michael Snyder, Lincoln Stein, Kevin White, Robert Waterston, Sarah C.R. Elgin

Biology Faculty Research

Despite the successes of genomics, little is known about how genetic information produces complex organisms. A look at the crucial functional elements of fly and worm genomes could change that.

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Fish Assemblages In Manistee River Tributaries: Longitudinal Distribution Analysis, Seasonal Variation, And Riparian Improvement Evaluation, Nicholas J. Gressick Jun 2009

Fish Assemblages In Manistee River Tributaries: Longitudinal Distribution Analysis, Seasonal Variation, And Riparian Improvement Evaluation, Nicholas J. Gressick

Masters Theses

Sedimentation affects both stream physical and biological integrity. Improperly designed stream passage accompanied with sedimentation and altered hydrology can impede fish passage and reduce fish assemblage integrity. The purpose of this study was to: 1) quantify impacts of poorly constructed road stream crossings and eroding banks on fish assemblages, and 2) assess these sites as sediment sources and connectivity breaks on entire fish assemblages and individual fish species. Electrofishing was conducted during spring and fall 2004 and 2005. A total of 29 electrofishing reaches were sampled which included 5 road-stream and streambank restoration sites. Sickle Creek (1st order) had reduced …

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What Drives Long-Distance Dispersal? A Test Of Theoretical Predictions, Winsor H. Lowe Jun 2009

What Drives Long-Distance Dispersal? A Test Of Theoretical Predictions, Winsor H. Lowe

Biological Sciences Faculty Publications

Long-distance dispersal (LDD) may contribute disproportionately to species persistence in fragmented landscapes, non-native invasions, and range shifts in response to climate change. However, direct data on LDD are extremely limited, leaving us with little understanding of why it occurs. I used six years of mark–recapture data on the stream salamander Gyrinophilus porphyriticus to test theoretical predictions of how variation in habitat quality affects LDD. Frequency of LDD was quantified using the kurtosis of yearly movement distributions from recaptured animals in a 1-km headwater stream. Temporal and spatial variation in habitat quality were quantified with spatially explicit data on the body …

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Molecular Data Are Transforming Hypotheses On The Origin And Diversification Of Eukaryotes, Yonas I. Tekle, Laura Wegener Parfrey, Laura A. Katz Jun 2009

Molecular Data Are Transforming Hypotheses On The Origin And Diversification Of Eukaryotes, Yonas I. Tekle, Laura Wegener Parfrey, Laura A. Katz

Biological Sciences: Faculty Publications

The explosion of molecular data has transformed hypotheses on both the origin of eukaryotes and the structure of the eukaryotic tree of life. Early ideas about the evolution of eukaryotes arose through analyses of morphology by light microscopy and, later, electron microscopy. Though such studies have proven powerful at resolving more recent events, theories on origins and diversification of eukaryotic life have been substantially revised in light of analyses of molecular data including gene and, increasingly, whole-genome sequences. By combining these approaches, progress has been made in elucidating the origin and diversification of eukaryotes. Yet many aspects of the evolution …

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Redescription Of The Frog Bladder Fluke Gorgoderina Attenuata From The Northern Leopard Frog, Rana Pipiens, Matthew G. Bolek, Scott D. Snyder, John J. Janovy Jr. Jun 2009

Redescription Of The Frog Bladder Fluke Gorgoderina Attenuata From The Northern Leopard Frog, Rana Pipiens, Matthew G. Bolek, Scott D. Snyder, John J. Janovy Jr.

Biology Faculty Publications

Morphological characters used to differentiate North American bladder flukes, Gorgoderina spp., are problematic and different authors use different morphological characteristics for distinguishing species. More importantly, no type specimens exist for four of the 12 North American species infecting anuran and caudatan hosts. A redescription of Gorgoderina attenuata (Stafford, 1902) Stafford, 1905 is based on new collections from 6 species of anurans from Arkansas, Nebraska, New York, and Wisconsin. Morphological comparisons between gravid G. attenuata recovered from bullfrogs and northern leopard frogs indicated statistically significant differences in 11 of 28 morphological characters examined. However, there was overlap among all of these …

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Guided Inquiry Lab Exercises In Development And Oxygen Consumption Using Zebrafish, Brian Bagatto Jun 2009

Guided Inquiry Lab Exercises In Development And Oxygen Consumption Using Zebrafish, Brian Bagatto

Biology Faculty Research

Zebrafish have become a model organism in many areas of research and are now being used with more frequency in the classroom to teach important biological concepts. The two guided inquiry exercises in this article are each aimed at a different level of instruction, but each can be modified to fit the needs of many high school or college-level courses. The "Zebrafish Development and Environment'' exercise teaches high school students about zebrafish development by presenting a series of embryos at different ages. Without access to visual references, students are asked to rank developing zebrafish by age and explain their choices. …

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Effects Of Hematocrit On Impedance And Shear Stress During Stenosed Artery Catheterization, V. P. Srivastava, Rati Rastogi Jun 2009

Effects Of Hematocrit On Impedance And Shear Stress During Stenosed Artery Catheterization, V. P. Srivastava, Rati Rastogi

Applications and Applied Mathematics: An International Journal (AAM)

The flow of blood through a stenosed catheterized artery has been studied. To observe the effects of hematocrit, blood has been represented by a two-phase macroscopic model (i.e., a suspension of red cells in plasma). It is found that for any given catheter size, the impedance increases with hematocrit and also for a given hematocrit, the same increases with the catheter size. In the stenotic region, the wall shear stress increases in the upstream of the stenosis throat and decreases in the downstream in an uncatheterized artery but the same possesses an opposite character in the case of a catheterized …

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Effect Of Glycocalyx On Red Blood Cell Motion In Capillary Surrounded By Tissue, Rekha Bali, Swati Mishra, P. N. Tandon Jun 2009

Effect Of Glycocalyx On Red Blood Cell Motion In Capillary Surrounded By Tissue, Rekha Bali, Swati Mishra, P. N. Tandon

Applications and Applied Mathematics: An International Journal (AAM)

The aim of the paper is to develop a simple model for capillary tissue fluid exchange system to study the effect of glycocalyx layer on the single file flow of red cells. We have considered the channel version of an idealized Krogh capillary-tissue exchange system. The glycocalyx and the tissue are represented as porous layers with different property parametric values. Hydrodynamic Lubrication theory is used to compute the squeezing flow of plasma within the small gap between the cell and the glycocalyx layer symmetrically surrounded by the tissue. The system of non linear partial differential equations has been solved using …

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Stability Of An Age-Structured Seir Epidemic Model With Infectivity In Latent Period, Xue-Zhi Li, Bin Fang Jun 2009

Stability Of An Age-Structured Seir Epidemic Model With Infectivity In Latent Period, Xue-Zhi Li, Bin Fang

Applications and Applied Mathematics: An International Journal (AAM)

We study an age-structured SEIR epidemic model with infectivity in the latent period. By using the theory and methods of Differential and Integral Equations, the explicit expression for the basic reproductive number R0 is first derived. It is shown that the disease-free equilibrium is locally and globally asymptotically stable if R0 < 1. It is then proved that only one endemic equilibrium exists if R0 > 1 and its stability conditions are also given.

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Phylogeographic And Phylogenetic Exploration Of Plethodon (Plethodontidae, Caudata) Salamanders In The Pacific Northwest, Tara Anne Pelletier Jun 2009

Phylogeographic And Phylogenetic Exploration Of Plethodon (Plethodontidae, Caudata) Salamanders In The Pacific Northwest, Tara Anne Pelletier

Dissertations and Theses

Genetic studies of amphibians often reveal substantial population structure due to either historical demographics from changing climate and geographic features over varying timeframes. Eight species of terrestrial salamanders (Family: Plethodontidae, Genus: Plethodon) reside in forests of the Pacific Northwest (PNW). Plethodon vehiculum is the most widespread and abundant terrestrial salamander in the PNW yet evolutionary studies are lacking. Using mitochondrial DNA (mtDNA) sequence data (D-loop and cytb) questions regarding the phylogeography of P. vehiculum and phylogenetics of western Plethodons are explored. Two major clades were defined in P. vehiculum, a southern clade in the Klamath-Siskiyou region and a …

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Andrews Student Awarded Goldwater Scholarship, Keri Suarez Jun 2009

Andrews Student Awarded Goldwater Scholarship, Keri Suarez

Lake Union Herald

No abstract provided.

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Inhibition Of Aβ42 Aggregation Using Peptides Selected From Combinatorial Libraries, Michael Baine, Daniel S. Georgie, Elelta Z. Shiferraw, Theresa P. T. Nguyen, Luiza A. Nogaj, David A. Moffet Jun 2009

Inhibition Of Aβ42 Aggregation Using Peptides Selected From Combinatorial Libraries, Michael Baine, Daniel S. Georgie, Elelta Z. Shiferraw, Theresa P. T. Nguyen, Luiza A. Nogaj, David A. Moffet

Chemistry and Biochemistry Faculty Works

Increasing evidence suggests that the aggregation of the small peptide Aβ42 plays an important role in the development of Alzheimer’s disease. Inhibiting the initial aggregation of Aβ42 may be an effective treatment for preventing, or slowing, the onset of the disease. Using an in vivo screen based on the enzyme EGFP, we have searched through two combinatorially diverse peptide libraries to identify peptides capable of inhibiting Aβ42 aggregation. From this initial screen, three candidate peptides were selected and characterized. ThT studies indicated that the selected peptides were capable of inhibiting amyloid aggregation. Additional ThT studies showed that one of the …

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Spatial, Seasonal, And Size-Dependent Variation In The Diet Of Sacramento Pikeminnow In The Main Stem Of Chorro Creek, Central Coast California, Brian G. Dugas Jun 2009

Spatial, Seasonal, And Size-Dependent Variation In The Diet Of Sacramento Pikeminnow In The Main Stem Of Chorro Creek, Central Coast California, Brian G. Dugas

Master's Theses

This study examined the diet composition of ninety-nine Sacramento pikeminnow (150-410 mm [5.9-16 in] fork length [FL]) collected from the upper and lower main stem of Chorro Creek, Morro Bay Watershed, California in 2006. The goal of this study was to characterize the spatial and seasonal variability in the diet of Sacramento pikeminnow within Chorro Creek and to determine what proportion of the diet is represented by rainbow trout (Oncorhynchus mykiss) and their anadromous form (steelhead). Prey was identified in 88% of the samples collected in the early season and 84% of the samples collected in the late season. Fish …

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Biological Effects Within No-Take Marine Reserves: A Global Synthesis, Sarah E. Lester, Benjamin S. Halpern, Kirsten Grorud-Colvert, Jane Lubchenco, Benjamin I. Ruttenberg, Steven D. Gaines, Satie Airamé, Robert R. Warner May 2009

Biological Effects Within No-Take Marine Reserves: A Global Synthesis, Sarah E. Lester, Benjamin S. Halpern, Kirsten Grorud-Colvert, Jane Lubchenco, Benjamin I. Ruttenberg, Steven D. Gaines, Satie Airamé, Robert R. Warner

Biological Sciences

The study and implementation of no-take marine reserves have increased rapidly over the past decade, providing ample data on the biological effects of reserve protection for a wide range of geographic locations and organisms. The plethora of new studies affords the opportunity to reevaluate previous findings and address formerly unanswered questions with extensive data syntheses. Our results show, on average, positive effects of reserve protection on the biomass, numerical density, species richness, and size of organisms within their boundaries which are remarkably similar to those of past syntheses despite a near doubling of data. New analyses indicate that (1) these …

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Effects Of Experience On Maternal Behavior In Belding’S Ground Squirrels (Spermophilus Beldingi): Older And Wiser?, Mikael Langner May 2009

Effects Of Experience On Maternal Behavior In Belding’S Ground Squirrels (Spermophilus Beldingi): Older And Wiser?, Mikael Langner

Master's Theses

Maternal behavior is an important behavior because it influences whether or not raising one’s offspring is successful. Maternal experience is positively correlated with successful maternal behavior. This association is evident when comparing first-time mothers with mothers who have prior experience raising young. Life experience not related to raising young can also positively influence maternal behavior. In this work, the hypothesis that is tested is whether or not maternal experience enhances the ability of a female to assess the threat level of a situation. The model species used to conduct the study is the Belding ground squirrel (Spermophilus beldingi), …

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Activity And Interactions Of Liposomal Antibiotics In Presence Of Polyanions And Sputum Of Patients With Cystic Fibrosis, Misagh Alipour, Zacharias E. Suntres, Majed Halwani, Ali Azghani, Abdelwahab Omri May 2009

Activity And Interactions Of Liposomal Antibiotics In Presence Of Polyanions And Sputum Of Patients With Cystic Fibrosis, Misagh Alipour, Zacharias E. Suntres, Majed Halwani, Ali Azghani, Abdelwahab Omri

Biology Faculty Publications and Presentations

Background: To compare the effectiveness of liposomal tobramycin or polymyxin B against Pseudomonas aeruginosa in the Cystic Fibrosis (CF) sputum and its inhibition by common polyanionic components such as DNA, F-actin, lipopolysaccharides (LPS), and lipoteichoic acid (LTA). Methodology: Liposomal formulations were prepared from a mixture of 1,2-Dimyristoyl-sn-Glycero-3-Phosphocholine (DMPC) or 1,2-Dipalmitoyl-sn-Glycero-3-Phosphocholine (DPPC) and Cholesterol (Chol), respectively. Stability of the formulations in different biological milieus and antibacterial activities compared to conventional forms in the presence of the aforementioned inhibitory factors or CF sputum were evaluated. Results: The formulations were stable in all conditions tested with no significant differences compared to the controls. …

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Insight Into The Carboxyl Transferase Domain Mechanism Of Pyruvate Carboxylase From Rhizobium Etli, Tonya N. Zeczycki, Martin St. Maurice, Sarawut Jitrapakdee, John C. Wallace, Paul V. Attwood, W Wallace Cleland May 2009

Insight Into The Carboxyl Transferase Domain Mechanism Of Pyruvate Carboxylase From Rhizobium Etli, Tonya N. Zeczycki, Martin St. Maurice, Sarawut Jitrapakdee, John C. Wallace, Paul V. Attwood, W Wallace Cleland

Biological Sciences Faculty Research and Publications

The effects of mutations in the active site of the carboxyl transferase domain of Rhizobium etli pyruvate carboxylase have been determined for the forward reaction to form oxaloacetate, the reverse reaction to form MgATP, the oxamate-induced decarboxylation of oxaloacetate, the phosphorylation of MgADP by carbamoyl phosphate, and the bicarbonate-dependent ATPase reaction. Additional studies with these mutants examined the effect of pyruvate and oxamate on the reactions of the biotin carboxylase domain. From these mutagenic studies, putative roles for catalytically relevant active site residues were assigned and a more accurate description of the mechanism of the carboxyl transferase domain is presented. …

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Immunodeficient Mouse Strains Display Marked Variability In Growth Of Human Melanoma Lung Metastases, Beatriz M. Carreno, Joel R. Garbow, Grant R. Kolar, Erin N. Jackson, John A. Engelbach, Michelle Becker-Hapak, Leonidas N. Carayannopoulos, David Piwnica-Worms, Gerald P. Linette May 2009

Immunodeficient Mouse Strains Display Marked Variability In Growth Of Human Melanoma Lung Metastases, Beatriz M. Carreno, Joel R. Garbow, Grant R. Kolar, Erin N. Jackson, John A. Engelbach, Michelle Becker-Hapak, Leonidas N. Carayannopoulos, David Piwnica-Worms, Gerald P. Linette

Biological Sciences Faculty Research & Creative Works

Purpose: Immunodeficient mice serve as critical hosts for transplantation of xenogeneic cells for in vivo analysis of various biological processes. Because investigators typically select one or two immunodeficient mouse strains as recipients, no comprehensive study has been published documenting differences in human tumor engraftment. Taking advantage of the increased metastatic potential of RhoC-expressing human (A375) melanoma cells, we evaluate four immunodeficient mouse strains: severe combined immunodeficiency (scid), nonobese diabetic (NOD)-scid, NOD-scid β2mnull, and NOD-scid IL2Rγ;null as xenograft tumor recipients. Experimental Design: Bioluminescence, magnetic resonance imaging, and histopathology were used to monitor serial tumor growth. Natural killer (NK) …

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Contribution Of Candida Albicans To The Synthesis Of The Volatile Organic Compound Ethanol In Putrefied Bodies, Chelsey Mozingo May 2009

Contribution Of Candida Albicans To The Synthesis Of The Volatile Organic Compound Ethanol In Putrefied Bodies, Chelsey Mozingo

Honors Theses

This experiment sought to determine if Candida albicans contributed to the production of the volatile organic compound ethanol in decomposing beef livers. The results this experiment proved to be inconclusive. This experiment showed no correlation between the amount the presence of Candida albicans and the production of the volatile organic compound ethanol based on the standard addition method. This may be indicative that VOC analysis is not an appropriate method for determining time of death based on a quantitative analysis of volatile organic compounds. However, the experimental design most likely needs be altered to accommodate a more accurate method of …

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Identification Of Potentially Pathogenic Yeast Species In Seagull Guano By Molecular Techniques, Tobias L. Banks May 2009

Identification Of Potentially Pathogenic Yeast Species In Seagull Guano By Molecular Techniques, Tobias L. Banks

Honors Theses

Although studies have been performed identifying bacteria present in seagull guano, limited studies have been done with fungi, leaving a significant gap in our knowledge of a potentially significant reservoir of human disease. If pathogenic fungi are being deposited by seagulls in their feces then it is possible that the Department of Health might elect to monitor sand, as well as water, for a broad spectrum of disease-causing microbes. Currently only water is tested for the presence of coliform bacteria. It is hypothesized that there are pathogenic yeast-like fungi present in the guano of seagulls, that these fungi are deposited …

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Initiating Chromosome Replication In E. Coli: It Makes Sense To Recycle, Alan C. Leonard, Julia E. Grimwade May 2009

Initiating Chromosome Replication In E. Coli: It Makes Sense To Recycle, Alan C. Leonard, Julia E. Grimwade

Biomedical Engineering and Sciences Faculty Publications

Initiating new rounds of Escherichia coli chromosome replication requires DnaA-ATP to unwind the replication origin, oriC, and load DNA helicase. In this issue of Genes & Development, Fujimitsu and colleagues (pp. 1221-1233) demonstrate that two chromosomal sites, termed DARS (DnaA-reactivating sequences), recycle inactive DnaA-ADP into DnaA-ATP. Fujimitsu and colleagues propose these sites are necessary to attain the DnaA-ATP threshold during normal growth and are important regulators of initiation timing in bacteria. © 2009 by Cold Spring Harbor Laboratory Press.

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Assesment Of Florida Bass, (Micropterus Floridanus), Stocking In Several Arkansas Lake Largemouth Bass, (M. Salmoides), Populations Using Microsatellite Analysis, Ryan Martin Allen May 2009

Assesment Of Florida Bass, (Micropterus Floridanus), Stocking In Several Arkansas Lake Largemouth Bass, (M. Salmoides), Populations Using Microsatellite Analysis, Ryan Martin Allen

Student Theses and Dissertations

Arkansas largemouth bass populations have been stocked with the exotic Florida bass for several decades to enhance lake fisheries. This study sampled 1,474 bass from eight Arkansas lakes to determine the success of introducing Florida bass alleles and hybridization events between bass species. Microsatellite data was then compared to historical allozyme data. Additionally, relationships were identified between Florida bass allele frequencies and lake characteristics as well as phenotypes and condition and length at age. A wide range of Florida bass allele frequencies were identified between lakes (10 - 70%), with the most highly correlated variable for successful stocking being reservoir …

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Closing The Seed Dispersal Loop For Guettarda Viburnoides (Rub.): Connecting Patterns Of Avian Seed Dispersal With Population Growth In A Neotropical Savanna, Andrea Patricia Loayza May 2009

Closing The Seed Dispersal Loop For Guettarda Viburnoides (Rub.): Connecting Patterns Of Avian Seed Dispersal With Population Growth In A Neotropical Savanna, Andrea Patricia Loayza

Dissertations

This study connects data on frugivore activity, post-dispersal seed fate and plant population demography using stage-specific demographic modeling to examine the role of individual dispersers for plant population dynamics of the fleshy-fruited Neotropical tree Guettarda viburnoides (Rubiaceae) in northeastern Bolivian savannas. Detailed information on frugivory and seed dispersal of G. viburnoides reveals that the endocarps of this plant are dispersed mainly by two species of birds: Cyanocorax cyanomelas and Pteroglossus castanotis, which are defined as the quantitatively important dispersers of G. viburnoides. These two species differ in several qualitative aspects of seed dispersal: 1) They select fruits of …

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Tritrophic Interactions In Forests: Direct And Indirect Interactions Between Birds, Insect Herbivores, And Oaks, Nicholas Anthony Barber May 2009

Tritrophic Interactions In Forests: Direct And Indirect Interactions Between Birds, Insect Herbivores, And Oaks, Nicholas Anthony Barber

Dissertations

This study examines direct and indirect relationships between three trophic levels to determine effects on plant damage, herbivore abundance and community structure, and bird distribution in forest ecosystems. Exclusion experiments on white oak (Quercus alba) revealed that bird predation effects to not vary spatially despite variation in abundance of both birds and insects. Using a leaf quality manipulation, I demonstrated that bird impacts do not differ with host plant quality. Rather, birds and plant traits had additive effects on herbivore damage. Bottom-up effects of leaf quality were also more important than top-down effects of birds in structuring the insect herbivore …

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