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- Title
- A Comparative Study on the Tensile Properties of Shark Skin.
- Creator
- Creager, Shelby, Porter, Marianne C., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Our goal was to assess regional differences in denticle density and skin tensile properties in four coastal species of shark. We hypothesized that the denticle density, tensile strength (MPa), stiffness (MPa), and toughness of skin (MJ·m^-3) would vary regionally along the body of an individual and among species. An hourglass-shaped punch was used to extract the skin samples at 10 anatomical landmarks and denticle density was quantified. Denticle density varied significantly among both...
Show moreOur goal was to assess regional differences in denticle density and skin tensile properties in four coastal species of shark. We hypothesized that the denticle density, tensile strength (MPa), stiffness (MPa), and toughness of skin (MJ·m^-3) would vary regionally along the body of an individual and among species. An hourglass-shaped punch was used to extract the skin samples at 10 anatomical landmarks and denticle density was quantified. Denticle density varied significantly among both regions and species, and showed a significant species by region interaction. Skin samples were tested in tension at a strain rate of 2 mm-s until failure. We found significant species and region effects for all tensile and denticle density properties. Also, denticle density increases with skin stiffness but decreases with toughness. Shark skin toughness is similar to that of mammalian tendons. These data show shark skin functions as an exotendon, able to conserve energy during swimming.
Show less - Date Issued
- 2016
- PURL
- http://purl.flvc.org/fau/fd/FA00004761, http://purl.flvc.org/fau/fd/FA00004761
- Subject Headings
- Sharks--Anatomy., Sharks--Locomotion., Surfaces (Physics), Biophysics.
- Format
- Document (PDF)
- Title
- A comparison of body proportions in juvenile sea turtles: how shape may optimize survival in a vulnerable life stage.
- Creator
- Pate, Jessica Hope, Salmon, Michael, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Marine turtles produce many offspring which offsets the high mortality experienced by turtles during early development. Juvenile mortality might be reduced by evolving effective behavioral as well as morphological anti-predator defenses. Body proportions of three species (Caretta caretta, Chelonia mydas, Dermochelys coriacea) of turtles were measured in the first fourteen weeks of development to examine how growth may mitigate predation by gape-limited predators. Growth was categorized as...
Show moreMarine turtles produce many offspring which offsets the high mortality experienced by turtles during early development. Juvenile mortality might be reduced by evolving effective behavioral as well as morphological anti-predator defenses. Body proportions of three species (Caretta caretta, Chelonia mydas, Dermochelys coriacea) of turtles were measured in the first fourteen weeks of development to examine how growth may mitigate predation by gape-limited predators. Growth was categorized as isometric if shape did not change during development or allometric if body shape did change. All three species showed allometric growth in carapace width; however it was less pronounced in the larger D. coriacea turtles. Allometric growth in carapace width decreased as all three species grew in size. When high predation occurs in early development, many species will favor rapid growth into a size refuge. Juvenile sea turtles may optimize their survival by growing allometrically when predation risk is the greatest.
Show less - Date Issued
- 2014
- PURL
- http://purl.flvc.org/fau/fd/FA00004223, http://purl.flvc.org/fau/fd/FA00004223
- Subject Headings
- Predation (Biology), Sea turtles -- Growth, Sea turtles -- Mortality, Sea turtles -- Population viability analysis
- Format
- Document (PDF)
- Title
- A generalized stochastic birth/death population model based on Indian RiverLagoon dolphins.
- Creator
- Stonger, Jon, Noonburg, Erik G., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
For over a decade, researchers at Harbor Branch Oceanographic Institute (HBOI) have conducted surveys of the bottlenose dolphin (Tursiops truncatus) population of Indian River Lagoon (IRL) in Florida. I have constructed a 4-stage population model using the statistical program R. The model is used to conduct a viability analysis by analyzing the relationship between birth, calf and adult survival rates. The power analysis compares survey frequency to expected confidence intervals in estimating...
Show moreFor over a decade, researchers at Harbor Branch Oceanographic Institute (HBOI) have conducted surveys of the bottlenose dolphin (Tursiops truncatus) population of Indian River Lagoon (IRL) in Florida. I have constructed a 4-stage population model using the statistical program R. The model is used to conduct a viability analysis by analyzing the relationship between birth, calf and adult survival rates. The power analysis compares survey frequency to expected confidence intervals in estimating abundance. The sensitivity analysis shows that the population is most sensitive to changes in adult survival, followed by birth rate and calf survival. The model shows a strong chance of viability over a 50 year time span. The population is vulnerable to long periods of decline if birth, calf or adult survival rates fall below certain thresholds. Overall, the model simulates the future impacts of demographic change, providing a tool for conservation efforts.
Show less - Date Issued
- 2014
- PURL
- http://purl.flvc.org/fau/fd/FA00004163, http://purl.flvc.org/fau/fd/FA00004163
- Subject Headings
- Animal populations -- Estimates, Bottlenose dolphin -- Florida -- Indian River Lagoon -- Geographical distribution, Indian River (Fla : Lagoon), Marine mammal populations -- Estimates -- Florida -- Mathematical models, Population biology, Stochastic processes
- Format
- Document (PDF)
- Title
- A habitat suitability model for wading birds in a large subtropical lake: linking hydrologic fluctuations and nesting.
- Creator
- Botta, Richard A., Gawlik, Dale E., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Anthropogenic hydrologic alterations can affect the quality of lake littoral zone habitats for wading birds, such as the great egret (Ardea alba), snowy egret (Egretta thula), and white ibis (Eudocimus albus). One such lake in Florida, Lake Okeechobee, has experienced a marked decline in wading bird nesting since the 1970’s, concomitant with changes in lake level management. It’s hypothesized that a reduction in foraging habitat has led to the nesting decline; however, there is little...
Show moreAnthropogenic hydrologic alterations can affect the quality of lake littoral zone habitats for wading birds, such as the great egret (Ardea alba), snowy egret (Egretta thula), and white ibis (Eudocimus albus). One such lake in Florida, Lake Okeechobee, has experienced a marked decline in wading bird nesting since the 1970’s, concomitant with changes in lake level management. It’s hypothesized that a reduction in foraging habitat has led to the nesting decline; however, there is little quantitative evidence of this link. A habitat suitability model was developed for Lake Okeechobee wading birds that incorporate the spatial and temporal dynamics of environmental factors that affect wading bird foraging and tests whether foraging habitat is linked to numbers of nests.
Show less - Date Issued
- 2014
- PURL
- http://purl.flvc.org/fau/fd/FA00004082
- Subject Headings
- Birds -- Florida -- Lake Okeechobee -- Geographical distribution, Estuarine ecology -- Florida -- Lake Okeechobee, Restoration ecology -- Florida -- Lake Okeechobee, Water birds -- Habitat
- Format
- Document (PDF)
- Title
- A Novel Interaction: The thin stripe hermit Crab, Clibanarius vittatus, kills the Florida crown conch, Melongena corona, for its shell.
- Creator
- Cutter, Jennifer, Devlin, Donna, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
The hermit crab Clibanarius vittatus kills Melongena corona solely to acquire a better fitting shell. This finding is contrary to previous studies, which found that hermit crabs of other species cannot kill gastropods or, in most instances, remove freshly dead gastropods from their shells. This interaction cannot be classified as predation because Melongena tissue was never consumed. Clibanarius killed Melongena only when by doing so they could trade up to a better fitting shell. It cannot be...
Show moreThe hermit crab Clibanarius vittatus kills Melongena corona solely to acquire a better fitting shell. This finding is contrary to previous studies, which found that hermit crabs of other species cannot kill gastropods or, in most instances, remove freshly dead gastropods from their shells. This interaction cannot be classified as predation because Melongena tissue was never consumed. Clibanarius killed Melongena only when by doing so they could trade up to a better fitting shell. It cannot be classified as competition because there is no opportunity for Melongena to gain from the interaction. Therefore the term “lethal eviction” is hereby proposed for this interaction. The ability to kill a gastropod to obtain a superior shell gives Clibanarius vittatus an evolutionary advantage over other hermit crab species. It is not known if the outcome of this interaction is widespread where both species occur or if it is confined to the study area.
Show less - Date Issued
- 2017
- PURL
- http://purl.flvc.org/fau/fd/FA00004925, http://purl.flvc.org/fau/fd/FA00004925
- Subject Headings
- Crabs--Behavior., Crab culture., Predation (Biology), Adaptation (Physiology), Aquatic ecology., Intertidal ecology., Conservation biology.
- Format
- Document (PDF)
- Title
- A Novel Role of the Ankyrin-Binding Motif of L1-Type CAM Neuroglian in Nuclear Import and Transcriptional Regulation of Myc.
- Creator
- Kakad, Priyanka P., Godenschwege, Tanja A., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
L1-type cell adhesion molecule (L1CAM) plays an essential role in the development of nervous system and is also highly relevant for the progression of diseases such as Alzheimer’s disease, stroke and cancers, some of the leading causes of human mortality. In addition to its canonical role as a plasma membrane protein organizing the cytoskeleton, recent in vitro studies have revealed that transmembrane as well as cytosolic fragments of proteolytically cleaved vertebrate L1CAM translocate to...
Show moreL1-type cell adhesion molecule (L1CAM) plays an essential role in the development of nervous system and is also highly relevant for the progression of diseases such as Alzheimer’s disease, stroke and cancers, some of the leading causes of human mortality. In addition to its canonical role as a plasma membrane protein organizing the cytoskeleton, recent in vitro studies have revealed that transmembrane as well as cytosolic fragments of proteolytically cleaved vertebrate L1CAM translocate to the nucleus and regulate expression of genes involved in DNA post-replication repair, cell cycle control, migration and differentiation. However, little is known about the in vivo function of L1CAM in the adult nervous system. This dissertation research focuses on studying in vivo nuclear translocation and function of L1CAM. Using the Drosophila model system, we first show that the sole Drosophila L1CAM homolog, Neuroglian (Nrg), is proteolytically cleaved by Alzheimer’s associated secretases, similar to L1CAM, and is also translocated to the nucleus in the adult nervous system. Subsequently, we have shown that the deletion of highly conserved Ankyrin binding domain or FIGQY motif disrupts nuclear import. Further experiments have revealed that the nuclear translocation of Nrg is in fact regulated by the phosphorylation of the FIGQY motif. Importantly, our studies also show transgenic expression of full-length Nrg or the intracellular domain of Nrg resulted in increased myc expression, which is associated with increased sensitivity to oxidative stress and reduced life span. On the other hand, deletion of the FIGQY motif or mutations preventing its phosphorylation led to decrease in myc expression. In summary, we have identified a novel role for the highly conserved Ankyrin binding domain in nuclear translocation and transcriptional regulation of the Drosophila myc oncogene, which is of high relevance to neurodegenerative diseases and cancer associated with oxidative stress.
Show less - Date Issued
- 2018
- PURL
- http://purl.flvc.org/fau/fd/FA00013076
- Subject Headings
- Cell adhesion molecules., Myc proteins., Transcription, Genetic., Transcription factors, Gene expression., Ankyrins., Translocation, Genetic.
- Format
- Document (PDF)
- Title
- A structural and thermodynamic comparison of substrate interactions and catalysis by family 6 glycosyltransferases from Bacteroides ovatus, Parachlamydia acanthamoebae, and Bos taurus.
- Creator
- Stinson, Brittany, Brew, Keith, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Family 6 Glycosyltransferases (GT6s) are involved in the biosynthesis of complex glycans and can be found in all vertebrates, cyanophages, and some bacteria and unicellular eukaryotes. Understanding variations within family 6 GTs is important because of the roles of their products in cellular recognition, intercellular interactions, pathogenicity, and immunity and is likewise important for understanding the evolution of GTs. PaGT6 (from Parchlamydia acanthamoebae) and α3GT (from Bos taurus)...
Show moreFamily 6 Glycosyltransferases (GT6s) are involved in the biosynthesis of complex glycans and can be found in all vertebrates, cyanophages, and some bacteria and unicellular eukaryotes. Understanding variations within family 6 GTs is important because of the roles of their products in cellular recognition, intercellular interactions, pathogenicity, and immunity and is likewise important for understanding the evolution of GTs. PaGT6 (from Parchlamydia acanthamoebae) and α3GT (from Bos taurus) both require a divalent metal ion for catalysis which binds to a DXD motif. In BoGT6a from Bacteroides ovatus a NXN motif replaces DXD, and activity is metal-independent. However, mutating the NXN motif in BoGT6a to DXD did not introduce metal-dependency, indicating that metal-dependency is linked to additional differences. Calorimetric studies have shown that the presence of a divalent metal ion enhances UDP and donor substrate binding to PaGT6 and causes an increase in the entropy of the interaction. Protein modelling of PaGT6 has revealed that the presence of Mn2+ allows a hydrogen bond to form between Asp 97 and UDP-GalNAc, causing the donor substrate to bend and form hydrogen bonds with His 119, Asn 229, Lys 228, and Arg 234. These interactions do not occur in the absence of Mn2+. Investigation of acceptor substrate binding revealed that the presence of UDP enhances acceptor substrate binding to BoGT6a and PaGT6. Calorimetric titrations of BoGT6a with 2-fucosyllactose in the absence and presence of UDP showed that UDP increases the affinity of 2-fucosyllactose 16-fold with little effect on ΔH. Measurements of ΔCp for 2-fucosyllactose binding indicate that there is not a hydrophobic effect for the binding of 2-fucosyllactose. The preferred acceptor substrate for the bovine and Bacteroides GT6 has a β-1,4 linked galactose, but P. acanthamoebae GT6 prefers an acceptor substrate with a β-1,3 linked galactose. The N-terminus of the catalytic domain of bacterial GT6s is truncated by 47 residues relative to the catalytic domain of bovine α3GT. Removal of this region from α3GT results in an unfolded protein, indicating that although this region is not directly involved in substrate binding, it forms interactions necessary for the stability of the catalytic domain.
Show less - Date Issued
- 2018
- PURL
- http://purl.flvc.org/fau/fd/FA00013047
- Subject Headings
- Glycosyltransferases, Bacteroides, Chlamydiales, Acanthamoeba, Bos taurus, Cattle
- Format
- Document (PDF)
- Title
- A Study on Reversing the Immunosuppressive Phenotype of Tumor Associated Macrophages.
- Creator
- Liddle, Genevieve M., Hartmann, James X., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Extracellular stimuli may influence the M1/M2 phenotypic polarization of macrophages. We examined M1/M2 biomarkers, phagocytic activity, and tumoricidal activity in RAW 264.7 mouse macrophages. Macrophages were treated with conditioned media (CM) from 4T1 breast cancer cells, curcumin, 22-oxacalcitriol, LPS, or a combination of the previously listed. Arginase activity, a M2 phenotypic biomarker, was upregulated by the treatment of macrophages with conditioned media. Curcumin, 22-...
Show moreExtracellular stimuli may influence the M1/M2 phenotypic polarization of macrophages. We examined M1/M2 biomarkers, phagocytic activity, and tumoricidal activity in RAW 264.7 mouse macrophages. Macrophages were treated with conditioned media (CM) from 4T1 breast cancer cells, curcumin, 22-oxacalcitriol, LPS, or a combination of the previously listed. Arginase activity, a M2 phenotypic biomarker, was upregulated by the treatment of macrophages with conditioned media. Curcumin, 22- oxacalcitriol, and LPS partially inhibited RAW 264.7 arginase activity in the presence of 4T1 breast cancer media. 22-oxacalcitriol increased the phagocytic ability of RAW 264.7 macrophages in the presence of M2 polarizing substances produced by the 4T1 breast cancer cells. Also, LPS increased RAW 264.7 phagocytic ability in the presence of 4T1 breast cancer CM. This study looked at the potential substances that would possibly reverse the M2 tumor promoting macrophage phenotype seen in the breast cancer tumor environment.
Show less - Date Issued
- 2017
- PURL
- http://purl.flvc.org/fau/fd/FA00004867
- Subject Headings
- Macrophages., Breast--Cancer--Treatment., Tumors--Immunological aspects., Cancer--Immunological aspects., Biological response modifiers., Cancer--Molecular aspects.
- Format
- Document (PDF)
- Title
- A Survey of Gopherus polyphemus Intestinal Parasites in South Florida.
- Creator
- Huffman, Jessica, Frazier, Evelyn, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Gopherus polyphemus populations are diminishing throughout their range due to urbanization, fragmentation, and poor management of habitats. Increased population densities, poor habitat quality, and lack of fire may influence disease transmission. Parasite roles within wild tortoise populations are largely unknown, despite evidence these pathogens may pose health risks. This study provides a baseline of gopher tortoise endoparasites across South Florida and reports on how varying environmental...
Show moreGopherus polyphemus populations are diminishing throughout their range due to urbanization, fragmentation, and poor management of habitats. Increased population densities, poor habitat quality, and lack of fire may influence disease transmission. Parasite roles within wild tortoise populations are largely unknown, despite evidence these pathogens may pose health risks. This study provides a baseline of gopher tortoise endoparasites across South Florida and reports on how varying environmental and tortoise characteristics may affect endoparasite species prevalence, approximate loads, and overall distributions. Tortoise fecal samples were taken from five differing SF habitats. Seven species of intestinal parasites were discovered from 123 tortoises. Identified parasites include endo-helminths such as cyathostomes, pinworms, ascarids, flukes, and protozoans including Eimeria, Cryptosporidium, and Amoeba species. Significant differences in parasite prevalence and loads were seen between sampling years, seasons, size classes, and sites, however, overall parasite distributions suggest parasitism remains relatively ubiquitous throughout most host and site characteristics.
Show less - Date Issued
- 2017
- PURL
- http://purl.flvc.org/fau/fd/FA00005024
- Subject Headings
- Dissertations, Academic -- Florida Atlantic University
- Format
- Document (PDF)
- Title
- Activators and repressors of transcription: using bioinformatics approaches to analyze and group human transcription factors.
- Creator
- Savitskaya, Ala., Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Transcription factors are macromolecules that are involved in transcriptional regulation by interacting with specific DNA regions, and they can cause activation or silencing of their target genes. Gene regulation by transcriptional control explains different biological processes such as development, function, and disease. Even though transcriptional control has been of great interest for molecular biology, much still remains unknown. This study was designed to generate the most current list...
Show moreTranscription factors are macromolecules that are involved in transcriptional regulation by interacting with specific DNA regions, and they can cause activation or silencing of their target genes. Gene regulation by transcriptional control explains different biological processes such as development, function, and disease. Even though transcriptional control has been of great interest for molecular biology, much still remains unknown. This study was designed to generate the most current list of human transcription factor genes. Unique entries of transcription factor genes were collected and entered into Microsoft Office 2007 Access Database along with information about each gene. Microsoft Office 2007 Access tools were used to analyze and group collected entries according to different properties such as activator or repressor record, or presence of certain protein domains. Furthermore, protein sequence alignments of members of different groups were performed, and phylogenetic trees were used to analyze relationship between different members of each group. This work contributes to the existing knowledge of transcriptional regulation in humans.
Show less - Date Issued
- 2010
- PURL
- http://purl.flvc.org/FAU/1930495
- Subject Headings
- Transcription factors, Genetic transcription, Regulation, Cellular signal transduction, DNA microarrays, Bioinformatics
- Format
- Document (PDF)
- Title
- Activity and Habitat Selection by Loggerhead (Caretta caretta L.) and Green Turtle (Chelonia mydas. L.) Hatchlings: A Laboratory and Field Study.
- Creator
- Smith, Morgan M., Salmon, Michael, Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
- Abstract/Description
-
Loggerhead and green turtle neonates migrate from Florida's coast during a 24-36 h frenzy. Post-frenzy loggerheads are often found in flotsam (Sargassum), while postfrenzy green turtles "disappear." This study compared the frenzy and post-frenzy activity of each species, their response to flotsam (in the laboratory and field), and the role of experience in habitat selection. Both species were most active during day I; activity thereafter declined (especially in loggerheads). Inactive...
Show moreLoggerhead and green turtle neonates migrate from Florida's coast during a 24-36 h frenzy. Post-frenzy loggerheads are often found in flotsam (Sargassum), while postfrenzy green turtles "disappear." This study compared the frenzy and post-frenzy activity of each species, their response to flotsam (in the laboratory and field), and the role of experience in habitat selection. Both species were most active during day I; activity thereafter declined (especially in loggerheads). Inactive loggerheads occupied Sargassum and open water (day or night) whereas inactive green turtles occupied Sargassum by day and both habitats at night. Exposure to Sargassum had no effect on the later habitat choices ofloggerheads, while exposed green turtles preferred Sargassum over plastic plants. In the field, both species preferred flotsam to open water, but occupied distinct microhabitats. Loggerheads preferred the mat surface while green turtles hid within the mat. Differences in activity and habitat selection likely reflect species-specific migratory and anti-predator strategies.
Show less - Date Issued
- 2007
- PURL
- http://purl.flvc.org/fau/fd/FA00000832
- Subject Headings
- Sea turtles--Ecology--Case studies, Wildlife conservation--Case studies, Habitat partitioning (Ecology), Adaptation (Biology)
- Format
- Document (PDF)
- Title
- Activity patterns of green iguana (Iguana iguana) at Hugh Taylor Birch State Park, Fort Lauderdale, Florida.
- Creator
- Sekscienski, Stacey R., Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Activity patterns of Iguana iguana from two locations within Hugh Taylor Birch State Park, Fort Lauderdale, Florida were documented and examined. Between May 1, 2006 to April 20, 2007, I. iguana were observed on a routine basis and activities were documented as one of six major activity categories (basking, locomotion, foraging, resting, visual signaling, and other). Data was analyzed to determine differences between activity patterns of I. iguana relative to sites, seasons, and size category...
Show moreActivity patterns of Iguana iguana from two locations within Hugh Taylor Birch State Park, Fort Lauderdale, Florida were documented and examined. Between May 1, 2006 to April 20, 2007, I. iguana were observed on a routine basis and activities were documented as one of six major activity categories (basking, locomotion, foraging, resting, visual signaling, and other). Data was analyzed to determine differences between activity patterns of I. iguana relative to sites, seasons, and size category within the park. Iguana iguana spent more time basking at Site 1 than Site 2. Size 4 animals which consisted of dominant adult males, spent more time basking than other males and adult females. Size 4 animals also spent less time foraging than hatchlings, juveniles, and other adults. These results complement the existing research on behavior of I. iguana and may be useful in determining invasive control efforts of I. iguana in Florida.
Show less - Date Issued
- 2012
- PURL
- http://purl.flvc.org/FAU/3359162
- Subject Headings
- Green iguana, Behavior, Adaptation (Biology)
- Format
- Document (PDF)
- Title
- Acute toxicity of the agricultural chemicals endosulfan and copper sulfate to a freshwater shrimp, Palaemonetes paludosus.
- Creator
- Kamthe, Prajakta Netaji, Florida Atlantic University, Baldwin, John D., Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
The toxicity of endosulfan, a restricted use pesticida, and copper sulfate, an anti-algal agent, ranks among the highest in all insecticidas. Both chemicals, used in agricultura fields of southern Florida, are known to be highly toxic to aquatic invertebrates. Since Palaemonetes pugio, an extensively studied brackish water shrimp species, has proven to be excellent for toxicological analysis, a closely related freshwater shrimp species, Palaemonetes paludosus, was used as the test species in...
Show moreThe toxicity of endosulfan, a restricted use pesticida, and copper sulfate, an anti-algal agent, ranks among the highest in all insecticidas. Both chemicals, used in agricultura fields of southern Florida, are known to be highly toxic to aquatic invertebrates. Since Palaemonetes pugio, an extensively studied brackish water shrimp species, has proven to be excellent for toxicological analysis, a closely related freshwater shrimp species, Palaemonetes paludosus, was used as the test species in this study to determine the toxicity of endosulfan and copper sulfate in freshwater. A series of static renewal 96 h bioassays (renewed every 24 h) performed on juvenile P. paludosus resulted in the 96 h lethal concentration (LC50) estimates of 0.24 mug/L (0.24 ppb) for endosulfan and 0.79 mg/L (0.79 ppm) for copper sulfate. The results of this study, when compared to other studies, indicate that P. paludosus is more sensitive to endosulfan and copper sulfate than other similar aquatic invertebrate species and is therefore an excellent toxicological indicator.
Show less - Date Issued
- 2002
- PURL
- http://purl.flvc.org/fcla/dt/12919
- Subject Headings
- Endosulfan--Toxicology, Palaemonetes, Copper sulfate--Toxicology
- Format
- Document (PDF)
- Title
- Aggressive Behaviors Of Adult Male Atlantic Spotted Dolphins (Stenella frontalis) During Intraspecific And Interspecific Aggressive Interactions.
- Creator
- Volker, Cassandra L., Herzing, Denise L., Hughes, Colin, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Atlantic spotted dolphins (Stenella frontalis) and bottlenose dolphins (Tursiops truncatus) are two sympatric species resident to the Bahamas. The visibility of the Bahamian water provided a unique opportunity to study spotted dolphin communication during aggression. This study’s main focus was to decipher any similarities or differences in the behaviors used by spotted dolphins during interspecific and intraspecific aggression. Both similarities and differences were discovered. Biting,...
Show moreAtlantic spotted dolphins (Stenella frontalis) and bottlenose dolphins (Tursiops truncatus) are two sympatric species resident to the Bahamas. The visibility of the Bahamian water provided a unique opportunity to study spotted dolphin communication during aggression. This study’s main focus was to decipher any similarities or differences in the behaviors used by spotted dolphins during interspecific and intraspecific aggression. Both similarities and differences were discovered. Biting, following, and chasing behavioral events were used more during interspecific aggression, while the display behavioral class was used more than the contact behavioral class during intrabut not interspecific aggression. This study showed that spotted dolphins use more energy intensive and risky behaviors when fighting interspecifically. This could result from having to fight and defend females from a larger species, trying to avoid sexual harassment from bottlenose males, or needing to use behaviors that are more overt and easily understood during interspecies communication.
Show less - Date Issued
- 2016
- PURL
- http://purl.flvc.org/fau/fd/FA00004638, http://purl.flvc.org/fau/fd/FA00004638
- Subject Headings
- Atlantic spotted dolphin--Bahamas., Aggressive behavior in animals., Social behavior in animals., Aquatic mammals--Behavior., Predation (Biology), Predatory marine animals--Ecology.
- Format
- Document (PDF)
- Title
- Alkaline Phosphatase Activity of Seagrass and Water Column Fractions in Florida Bay.
- Creator
- Kletou, Demetris, Koch-Rose, Marguerite, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Few phosphorus (P) depleted coastal marine ecosystems have been examined for their capacity to hydrolyze phosphomonoesters (PMEs). The purpose of this study was to examine seasonal APA partitioning between water column fractions (phytoplankton, bacteria and freely dissolved) and benthic autotrophs in Florida Bay, a P limited shallow estuary using low fluorescent substrate (MUF-P) concentrations (≤2.0 μm). APA was higher at the western and northcentral (751 and 695 nmol L^-1 h^-1) sites and...
Show moreFew phosphorus (P) depleted coastal marine ecosystems have been examined for their capacity to hydrolyze phosphomonoesters (PMEs). The purpose of this study was to examine seasonal APA partitioning between water column fractions (phytoplankton, bacteria and freely dissolved) and benthic autotrophs in Florida Bay, a P limited shallow estuary using low fluorescent substrate (MUF-P) concentrations (≤2.0 μm). APA was higher at the western and northcentral (751 and 695 nmol L^-1 h^-1) sites and driven by cyanobacterial blooms, compared to the P limited northeastern (359 nmol L^-1 h^-1) site The free dissolved fraction (<0.2 μm) accounted for the most APA (~50%), followed by the phytoplankton (>1 μm; 30%) and bacteria fraction (<0.2-> 1.2 μm; 8%). Thaiassia testudinum leaves with their associated epiphytes contributed modestly to water column APA (14 and 20%), and only during non-bloom conditions. Rapid hydrolysis of PMEs (undetected in most samplings) in Florida Bay is probably driven by high concentration of organic substrates for microbial and cyanobacterial activity which results from the close association of the shallow water column with the underlying seagrass community and adjacent Everglades wetlands.
Show less - Date Issued
- 2007
- PURL
- http://purl.flvc.org/fau/fd/FA00000780
- Subject Headings
- Coastal ecology--Florida, Coastal zone management--Florida, Estuarine sediments--Florida--Florida Bay, Aquaculture--Environmental aspects--Florida
- Format
- Document (PDF)
- Title
- Alternative Biological Roles of Methionine Sulfoxide Reductases in Drosophila melanogaster.
- Creator
- Wilson, Kelsey, Binninger, David, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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The oxidation of methionine (Met) into methionine sulfoxide (met-(o)) leads to deleterious modifications to a variety of cellular constituents. These deleterious alterations can be reversed by enzymes known as methionine sulfoxide reductases (Msr). The Msr (MsrA and MsrB) family of enzymes have been studied extensively for their biological roles in reducing oxidized Met residues back into functional Met. A wide range of studies have focused on Msr both in vivo and in vitro using a variety of...
Show moreThe oxidation of methionine (Met) into methionine sulfoxide (met-(o)) leads to deleterious modifications to a variety of cellular constituents. These deleterious alterations can be reversed by enzymes known as methionine sulfoxide reductases (Msr). The Msr (MsrA and MsrB) family of enzymes have been studied extensively for their biological roles in reducing oxidized Met residues back into functional Met. A wide range of studies have focused on Msr both in vivo and in vitro using a variety of model organisms. More specifically, studies have noted numerous processes affected by the overexpression, under expression, and silencing of MsrA and MsrB. Collectively, the results of these studies have shown that Msr is involved in lifespan and the management of oxidative stress. More recent evidence is emerging that supports existing biological functions of Msr and theorizes the involvement of Msr in numerous biological pathways.
Show less - Date Issued
- 2018
- PURL
- http://purl.flvc.org/fau/fd/FA00005980
- Subject Headings
- Drosophila melanogaster, Methionine Sulfoxide Reductases, Oxidative stress
- Format
- Document (PDF)
- Title
- An Assessment of Fecal Pollution in the St. Lucie Estuary and Indian River Lagoon.
- Creator
- Perricone, Carlie S., McCarthy, Peter J., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Contamination of recreational waters with fecal waste, indicated by the presence of enterococci, can have consequences for human and ecosystem health. The difficulty in determining the extent and origin of fecal pollution in dynamic estuarine systems is compounded by contributions from sources including septic tanks and agricultural runoff. This study investigated fecal pollution at five sites with variable hydrological conditions in the St. Lucie Estuary and Indian River Lagoon. The...
Show moreContamination of recreational waters with fecal waste, indicated by the presence of enterococci, can have consequences for human and ecosystem health. The difficulty in determining the extent and origin of fecal pollution in dynamic estuarine systems is compounded by contributions from sources including septic tanks and agricultural runoff. This study investigated fecal pollution at five sites with variable hydrological conditions in the St. Lucie Estuary and Indian River Lagoon. The distribution and occurrence of enterococci was assessed using traditional cultivation. A human-associated microbial source tracking assay was validated and applied in these estuaries using qPCR. Results demonstrated a correlation between enterococci concentrations, rainfall, and salinity. The human-associated assay was sensitive and specific in the lab; however, human fecal pollution was not detected in the field even though samples contained high levels of enterococci. This study highlights the importance of expanding the range of water quality assessment.
Show less - Date Issued
- 2017
- PURL
- http://purl.flvc.org/fau/fd/FA00005023
- Subject Headings
- Dissertations, Academic -- Florida Atlantic University
- Format
- Document (PDF)
- Title
- An investigation of membrane transporter proteins in the distal vertebrate retina: excitatory amino acid transporters and sodium potassium chloride cotransporters.
- Creator
- Purpura, Lauren Angeline, Shen, Wen, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Neurons are able to maintain membrane potential and synaptic integrity by an intricate equilibrium of membrane transporter proteins and ion channels. Two membrane proteins of particular importance in the vertebrate retina are the excitatory amino acid transporters (EAATs) which are responsible for the reuptake of glutamate into both glial and neuronal cells and the sodium potassium chloride cotransporters (NKCCs) that are responsible for the uptake of chloride ions into the cell. NKCCs are...
Show moreNeurons are able to maintain membrane potential and synaptic integrity by an intricate equilibrium of membrane transporter proteins and ion channels. Two membrane proteins of particular importance in the vertebrate retina are the excitatory amino acid transporters (EAATs) which are responsible for the reuptake of glutamate into both glial and neuronal cells and the sodium potassium chloride cotransporters (NKCCs) that are responsible for the uptake of chloride ions into the cell. NKCCs are electro-neutral with the uptake of 2 Cl- coupled to an exchange of a potassium and Na+ ion into the cells. Therefore, there is little change of cell membrane potential in the action of NKCCs. In this study the localization and function of EAATs in the distal retina is investigated. Whole cell patch clamp recordings in lower vertebrate retina have demonstrated that EAAT2 is the main synaptic EAATs in rod photoreceptors and it is localized to the axon terminals. Furthermore, the action of the transporter seems to be modified by intracellular calcium concentration. There is also evidence that EAAT2 might be regulated by feedback from the neuron network by glycinergic and GABAergic mechanisms. The second half of this study investigates expression of NKCCs in the retina by western blot analysis and quantitative polymerase chain reaction. There are two forms of NKCCs, NKCC1 and NKCC2. NKCC1 is mostly expressed in the central nervous system and NKCC2 was thought to only be expressed in the kidneys. NKCC1 is responsible for the majority of chloride uptake into neuronal and epithelial cells and NKCC1 is expressed in the distal retina where photoreceptors synapse on second order horizontal and bipolar cells. This study found the expression of NKCC1 in the distal retina to be regulated by temporal light and dark adaptation. Light adaptation increased phosphorylated NKCC1 expression (the active form of the cotransporter). The increase in NKCC1 expression during light adaptation was modulated by dopamine. Specifically, a D1 receptor agonist increased phosphorylated NKCC1 expression. Dopamine is an essential chemical and receptor known for initiating light adaptation in retina. Finally, an NKCC1 knockout mouse model was examined and it revealed that both forms of NKCC are expressed in the vertebrate retina.
Show less - Date Issued
- 2014
- PURL
- http://purl.flvc.org/fau/fd/FA00004224, http://purl.flvc.org/fau/fd/FA00004224
- Subject Headings
- Biological transport, Carrier proteins, Cellular signal transduction, Neural receptors, Retina -- Cytology
- Format
- Document (PDF)
- Title
- Analysis of morphology, growth rate, and fragmentation of the endangered lichen species Cladonia Perforata.
- Creator
- Witmer, David Warren, Moore, Jon, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Cladonia perforata is an endangered lichen endemic to the Atlantic Coastal Ridge, Lake Wales Ridge, Southwest Florida, and the North Gulf Coast of Florida. In all but a single locality, C. perforata relies entirely on asexual reproduction through fragmentation for reproduction, dispersal, and recruitment. This study suggests a positive correlation between fragment size and survivability of fragments after one year. The average thallus grew at a rate of 10.42% per year and younger branches of...
Show moreCladonia perforata is an endangered lichen endemic to the Atlantic Coastal Ridge, Lake Wales Ridge, Southwest Florida, and the North Gulf Coast of Florida. In all but a single locality, C. perforata relies entirely on asexual reproduction through fragmentation for reproduction, dispersal, and recruitment. This study suggests a positive correlation between fragment size and survivability of fragments after one year. The average thallus grew at a rate of 10.42% per year and younger branches of a thallus grew at a quicker rate than older branches. Additionally, a review of thalli morphology suggests C. perforata has a diverse form, and becomes more bifurcated as it increases in size.
Show less - Date Issued
- 2014
- PURL
- http://purl.flvc.org/fau/fd/FA00004172, http://purl.flvc.org/fau/fd/FA00004172
- Subject Headings
- Cladonia, Fragmented landscapes, Lichens -- North America, Symbiosis
- Format
- Document (PDF)
- Title
- Analysis of the Role of Autophagy in Dauer Formation and Dauer Recovery Regulated by TGF-β Signaling Pathway in Caenorhabditis elegans.
- Creator
- Ritter, Portia, Jia, Kailiang, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Caenorhabditis elegans optionally enter into a dauer diapause phase that results in a prolonged life in a semi-dormant state. Entry into and recovery from dauer diapause includes many physical changes in body structure, physiology, and gene expression. Entry into dauer diapause is regulated by several signaling pathways including transforming growth factor (TGF-β). Autophagy plays an important role in dauer formation and recover. During dauer transformation autophagy is up-regulated and may...
Show moreCaenorhabditis elegans optionally enter into a dauer diapause phase that results in a prolonged life in a semi-dormant state. Entry into and recovery from dauer diapause includes many physical changes in body structure, physiology, and gene expression. Entry into dauer diapause is regulated by several signaling pathways including transforming growth factor (TGF-β). Autophagy plays an important role in dauer formation and recover. During dauer transformation autophagy is up-regulated and may play a role in remodeling the molecular structure for long term survival during dauer diapause. This research helps determine the role of autophagy in dauer development and recovery mediated through the TGF-β signaling pathway. This research also determines in which tissue autophagy is necessary for dauer formation and recovery through TGF-β signaling. This research is shedding light on the function of autophagy in the TGF-β signaling pathway, both processes of which have been linked to tumorigenesis, heart disease and cancer.
Show less - Date Issued
- 2017
- PURL
- http://purl.flvc.org/fau/fd/FA00004921, http://purl.flvc.org/fau/fd/FA00004921
- Subject Headings
- Aging--Molecular aspects., Aging--Physiological aspects., Caenorhabditis elegans--Molecular genetics., Autophagic vacuoles., Gene expression., Apoptosis., Cellular signal transduction., DNA-binding proteins., Transforming growth factors-beta--Receptors.
- Format
- Document (PDF)