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- Title
- EXPOSURE TO ALGAL BIOTOXINS: EXPLORING HEALTH EFFECTS IN GREEN SEA TURTLES (CHELONIA MYDAS).
- Creator
- Brown, Hunter, Page, Annie, Florida Atlantic University, Department of Marine Science and Oceanography, Charles E. Schmidt College of Science
- Abstract/Description
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In the inter-coastal waters of Florida, green sea turtles (Chelonia mydas) are regularly exposed to regional blooms of harmful algae which produce biotoxins. A retrospective analysis was conducted on stranded green sea turtles along the Indian River Lagoon, FL, USA. Stranding, necropsy, and histopathology reports were analyzed for 40 juvenile turtles. Liver (N=40) and kidney (N=36) tissues were analyzed for a suite of 14 harmful algal bloom (HAB)-associated biotoxins. Thirty-four (85%)...
Show moreIn the inter-coastal waters of Florida, green sea turtles (Chelonia mydas) are regularly exposed to regional blooms of harmful algae which produce biotoxins. A retrospective analysis was conducted on stranded green sea turtles along the Indian River Lagoon, FL, USA. Stranding, necropsy, and histopathology reports were analyzed for 40 juvenile turtles. Liver (N=40) and kidney (N=36) tissues were analyzed for a suite of 14 harmful algal bloom (HAB)-associated biotoxins. Thirty-four (85%) turtles tested positive for at least one biotoxin, including 21(53%) liver and 22(61%) kidney tissues. Statistically significant relationships were identified between the presence of common histopathological abnormalities and biotoxins of: melanomacrophage/hyperplasia and brevetoxin-3 (P=0.03) in liver tissues, and renal fibrosis and nodularin (P = 0.04) and lymphocytosis and neosaxitoxin (P=0.03) in kidney tissues. These data demonstrate that wild turtles are commonly exposed to HAB-associated biotoxins with potential chronic health effects that contribute to strandings in the Indian River Lagoon.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014363
- Subject Headings
- Chelonia mydas, Green sea turtles, Algal toxins, Indian River (Fla. : Lagoon)
- Format
- Document (PDF)
- Title
- TIMELINE OF NUTRIENT INCORPORATION FROM BROODSTOCK DIET TO EGG IN CALIFORNIA YELLOWTAIL, SERIOLA DORSALIS.
- Creator
- Chin, Li Sun, Mejri, Sahar, Florida Atlantic University, Department of Marine Science and Oceanography, Charles E. Schmidt College of Science
- Abstract/Description
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Existing brood fish research has ascertained that eggs are heavily influenced by broodstock diet but there is no information regarding this timeline of nutritional incorporation. The objective of this study is to determine duration of nutritional incorporation from diet to eggs through fatty acids. Nine California Yellowtail (Seriola dorsalis) broodstock were fed alternating diets of commercial pellets (Vitalis PRIMA: Skretting) and cutbait. Biochemical and biometric data from spawns were...
Show moreExisting brood fish research has ascertained that eggs are heavily influenced by broodstock diet but there is no information regarding this timeline of nutritional incorporation. The objective of this study is to determine duration of nutritional incorporation from diet to eggs through fatty acids. Nine California Yellowtail (Seriola dorsalis) broodstock were fed alternating diets of commercial pellets (Vitalis PRIMA: Skretting) and cutbait. Biochemical and biometric data from spawns were collected and analyzed for differences and similarities throughout the alternating diets. Eggs were observed to selectively incorporate higher sources of linolenic and linoleic acid from the pelleted diet, and eicosapentaenoic acid from the cutbait diet. Interestingly, results showed overall fatty acids from both diets were fully incorporated by eggs within 9 days following the diet switch. These findings provided new insight towards the selective incorporation of nutrients and will open new doors for future broodstock nutrition research.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014327
- Subject Headings
- Seriola dorsalis, Yellowtail, Aquaculture, Fishes—Feeding and feeds, Brood stock assessment
- Format
- Document (PDF)
- Title
- SHALLOW-WATER ENCRUSTERS AND THE TAPHONOMY OF THE HOLOCENE STORM RIDGE OFF POMPANO BEACH, BROWARD COUNTY, FLORIDA.
- Creator
- Ciesinski, Carson Park, Oleinik, Anton, Florida Atlantic University, Department of Geosciences, Charles E. Schmidt College of Science
- Abstract/Description
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Encrusters have a proven history as indicators of environmental conditions in nearshore habitats and are useful in both ecological and paleoenvironmental research within benthic ecosystems. Off the coast of Pompano Beach, Florida, a Holocene storm deposit contains large accumulations of subfossil Acropora palmata fragments with these same encrusting organisms attached to their surfaces. The objective of this research was to create an inventory of encrusters found within the storm deposit and...
Show moreEncrusters have a proven history as indicators of environmental conditions in nearshore habitats and are useful in both ecological and paleoenvironmental research within benthic ecosystems. Off the coast of Pompano Beach, Florida, a Holocene storm deposit contains large accumulations of subfossil Acropora palmata fragments with these same encrusting organisms attached to their surfaces. The objective of this research was to create an inventory of encrusters found within the storm deposit and document their successional outgrowth to determine the post-depositional history of sampled coral fragments. Foraminifera and coralline algae were the most common species found, and various sequences of successional outgrowth were observed that indicated fragments were either deposited gradually, immediately buried, or reworked after initial burial. This information is vital for understanding modern biodiversity on the Pompano coast, and the development of nearshore benthic marine ecosystems during the mid-late Holocene.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014344
- Subject Headings
- Taphonomy, Corals, Acropora palmata, Pompano Beach (Fla.), Environmental sciences
- Format
- Document (PDF)
- Title
- REEF WARS: MONITORING AND PREDICTING PHASE SHIFTS ON FLORIDA CORAL REEFS.
- Creator
- Conkling, Megan, Pomponi, Shirley A., Hindle, Tobin, Florida Atlantic University, Department of Geosciences, Charles E. Schmidt College of Science
- Abstract/Description
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Reefs off the coast of Florida face threats from stressors associated with climate change which leads to phase shifts. Under rapid climate change, a clear understanding of how reefs and their benthic organisms respond is still lacking and needs to be investigated. Using in situ imagery, a sponge cell model, and long-term benthic biota surveys, the effects of climate change on reef dynamics were explored in this dissertation project. Results from the in situ imagery found that differences in...
Show moreReefs off the coast of Florida face threats from stressors associated with climate change which leads to phase shifts. Under rapid climate change, a clear understanding of how reefs and their benthic organisms respond is still lacking and needs to be investigated. Using in situ imagery, a sponge cell model, and long-term benthic biota surveys, the effects of climate change on reef dynamics were explored in this dissertation project. Results from the in situ imagery found that differences in spectral signatures are found between functional groups (i.e., corals, sponges, and algae) and different species from substrate. Results based on a sponge cell model and transcriptomics data have found a resilience of these sponges to the predicted thermal extremes. Results from benthic biota surveys suggested that depth and light attenuation have the largest influence on the predicted distribution of corals, sponges, and algae at Pulley Ridge. Climate change has been impacting reef benthic biota starting at the organismal scale up to the reef scale. This research demonstrates the importance of monitoring reefs at a finer scale and determining the thresholds and limits of benthic biota to projected thermal extremes to better inform resource managers to preserve these irreplaceable ecosystems.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014323
- Subject Headings
- Reefs--Florida, Climate change, Coral reef ecology
- Format
- Document (PDF)
- Title
- MITOCHONDRIAL GENETIC DIVERSITY OF THE RED-TAILED MONKEY, CERCOPITHECUS ASCANIUS, IN AFRICAN RAINFORESTS.
- Creator
- Dutra, Vitor Daniel, Detwiler, Kate M., Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
- Abstract/Description
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Cercopithecus ascanius is an African primate species encompassing five geographic types with unresolved taxonomy. Recent publications have analyzed C. ascanius genetic diversity and taxonomy; however, few publications have addressed the genetic diversity and phylogenetic relationships of C. ascanius from wild populations. My objectives for this thesis were to determine mtDNA diversity within the C. Ascanius species and investigate C. ascanius genetic structure. Results from this thesis...
Show moreCercopithecus ascanius is an African primate species encompassing five geographic types with unresolved taxonomy. Recent publications have analyzed C. ascanius genetic diversity and taxonomy; however, few publications have addressed the genetic diversity and phylogenetic relationships of C. ascanius from wild populations. My objectives for this thesis were to determine mtDNA diversity within the C. Ascanius species and investigate C. ascanius genetic structure. Results from this thesis support findings from previous studies wherein C. ascanius depicted high mitochondrial diversity and all C. ascanius subspecies form a monophyletic clade within the Cercopithecus genus. Analyzing additional samples of C. ascanius monkeys will strengthen molecular diversity estimation and clarify genetic structure within the C. ascanius lineage.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014325
- Subject Headings
- Mitochondrial DNA, Cercopithecus ascanius, Genetics, Phylogeny
- Format
- Document (PDF)
- Title
- FACIAL EXPRESSION PROCESSING IN AUTISM SPECTRUM DISORDER AS A FUNCTION OF ALEXITHYMIA: AN EYE MOVEMENT STUDY.
- Creator
- Escobar, Brian, Hong, Sang Wook, Florida Atlantic University, Department of Psychology, Charles E. Schmidt College of Science
- Abstract/Description
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The perception and interpretation of faces provides individuals with a wealth of knowledge that enables them to navigate their social environments more successfully. Prior research has hypothesized that the decreased facial expression recognition (FER) abilities observed in autism spectrum disorder (ASD) may be better explained by comorbid alexithymia, the alexithymia hypothesis. The present study sought to further examine the alexithymia hypothesis by collecting data from 59 participants and...
Show moreThe perception and interpretation of faces provides individuals with a wealth of knowledge that enables them to navigate their social environments more successfully. Prior research has hypothesized that the decreased facial expression recognition (FER) abilities observed in autism spectrum disorder (ASD) may be better explained by comorbid alexithymia, the alexithymia hypothesis. The present study sought to further examine the alexithymia hypothesis by collecting data from 59 participants and examining FER performance and eye movement patterns for ASD and neurotypical (NT) individuals while controlling for alexithymia severity. Eye movement-related differences and similarities were examined via eye tracking in conjunction with statistical and machine-learning-based pattern classification analysis. In multiple different classifying conditions, where the classifier was fed 1,718 scanpath images (either at spatial, spatial-temporal, or spatial temporal-ordinal levels) for high-alexithymic ASD, high-alexithymicvi NT, low-alexithymic ASD, and low-alexithymic NT, we could accurately decode significantly above chance level. Additionally, in the cross-decoding analysis where the classifier was fed 1,718 scanpath images for high- and low alexithymic ASD individuals and tested on high- and low-alexithymic NT individuals, results showed that classification accuracy was significantly above chance level when using spatial images of eye movement patterns. Regarding FER performance results, we found that ASD and NT groups performed similarly, but at lower intensities of expressions, ASD individuals performed significantly worse than NT individuals. Together, these findings suggest that there may be eye-movement related differences between ASD and NT individuals, which may interact with alexithymia traits.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014358
- Subject Headings
- Autism Spectrum Disorder, Machine learning, Facial expression, Alexithymia, Eye tracking
- Format
- Document (PDF)
- Title
- The Dynamic pH Landscape At The Drosophila NMJ Synaptic Cleft And Its Implication In Neurotransmission.
- Creator
- Hernandez, Roberto X., Macleod, Gregory T., Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
- Abstract/Description
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The intricate processes governing cellular pH and its impact on protein and cellular function have been extensively explored. However, our understanding of the pH fluctuations that occur during routine cellular activities and their potential to modulate cell function remains, particularly within the highly dynamic pH landscape of a synapse. Investigating the scale, directionality, and temporal characteristics of these activity-dependent pH fluctuations at synapses is of paramount interest, as...
Show moreThe intricate processes governing cellular pH and its impact on protein and cellular function have been extensively explored. However, our understanding of the pH fluctuations that occur during routine cellular activities and their potential to modulate cell function remains, particularly within the highly dynamic pH landscape of a synapse. Investigating the scale, directionality, and temporal characteristics of these activity-dependent pH fluctuations at synapses is of paramount interest, as it carries profound implications for neurotransmitter release and signal transduction. Employing both empirical and computational modeling methods, our research explores the dynamic pH environment within the synaptic cleft of Drosophila glutamatergic motor neuron Ib terminals during synaptic activity and reveals its significance in modulating neurotransmission. Contrary to popular belief, we discovered that these terminals undergo activity-dependent extracellular alkalinization in response to both single action potentials and burst stimulation. This surprising phenomenon was also observed at the mouse calyx of Held. We found activity-dependent alkalinization to be predominantly driven by Ca2+ movement across the postsynaptic membrane, and by targeting pH indicators to subcellular domains, we identified alkalinization to primarily occur within the cleft.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014346
- Subject Headings
- Neurotransmission, Drosophila, Hydrogen-Ion Concentration, Motor Neurons, Optogenetics
- Format
- Document (PDF)
- Title
- Vertical Ecology and Diversity of Melamphaes (Family Melamphaidae) in the Northern Gulf of Mexico Following the Deepwater Horizon Oil Spill.
- Creator
- Howard, Natalie, Moore, Jon A., Florida Atlantic University, Department of Marine Science and Oceanography, Charles E. Schmidt College of Science
- Abstract/Description
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The Deepwater Horizon Oil Spill had widespread impacts that were seen across the surface of the ocean, deep-sea, and seafloor. To assess damages, NOAA and GoMRI established the Offshore Nekton Sampling and Analysis Program (ONSAP) and the Deep Pelagic Nekton Dynamics of the Gulf of Mexico (DEEPEND) projects. This response effort would create a vast dataset and collection of samples to aid in understanding the deep-sea of the northern Gulf of Mexico. Genus Melamphaes (Family Melamphaidae), are...
Show moreThe Deepwater Horizon Oil Spill had widespread impacts that were seen across the surface of the ocean, deep-sea, and seafloor. To assess damages, NOAA and GoMRI established the Offshore Nekton Sampling and Analysis Program (ONSAP) and the Deep Pelagic Nekton Dynamics of the Gulf of Mexico (DEEPEND) projects. This response effort would create a vast dataset and collection of samples to aid in understanding the deep-sea of the northern Gulf of Mexico. Genus Melamphaes (Family Melamphaidae), are a group of minimally characterized and understudied fish. This thesis will assess vertical ecology and migratory patterns, variations in specimen size and sampling gear, and introduce species that are newly identified to inhabit the area. The findings suggest that majority of Melamphaes participate in diel vertical migration and sampling equipment has significant impacts on specimen size. Four unreported species of Melamphaes have now been documented in this region, increasing previously reported diversity.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014348
- Subject Headings
- BP Deepwater Horizon Explosion and Oil Spill, 2010, Mexico, Gulf of, Melamphaidae, Aquatic ecology
- Format
- Document (PDF)
- Title
- FRAZZLED/DCC REGULATES SYNAPTOGENESIS AT A DROSOPHILA GIANT SYNAPSE.
- Creator
- Lopez, Juan, Murphey, Rodney, Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
- Abstract/Description
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Synaptogenesis is a requirement for cellular communication, but the specific molecular mechanisms underlying synaptogenesis are unclear. Here, we investigate and show the role of the protein Frazzled in synaptogenesis using the transheterozygous Frazzled loss-of-function (LOF) mutant in Drosophila. Leveraging the UAS-GAL4 expression system, we drove expression of various Frazzled/DCC gene constructs in the Giant Fibers (GF) of flies and found changes to synaptogenesis and axon pathfinding. We...
Show moreSynaptogenesis is a requirement for cellular communication, but the specific molecular mechanisms underlying synaptogenesis are unclear. Here, we investigate and show the role of the protein Frazzled in synaptogenesis using the transheterozygous Frazzled loss-of-function (LOF) mutant in Drosophila. Leveraging the UAS-GAL4 expression system, we drove expression of various Frazzled/DCC gene constructs in the Giant Fibers (GF) of flies and found changes to synaptogenesis and axon pathfinding. We identified decreases in electrical synaptogenesis and distinct axon pathfinding errors in Frazzled LOF mutants. Strikingly, the expression of Frazzled intracellular domain (ICD) significantly rescues both phenotypes, while full-length Frazzled protein only partially rescues these phenotypes, prompting us to explore the role of different domains within the protein. Deleting the P1 and P2 domains of Frazzled does not rescue axon pathfinding but did partially rescue synaptogenesis while deleting the P3 domain failed to rescue either phenotype. Moreover, when we drive expression Frazzled with a point-mutated P3 domain, silencing its transcriptional activation domain, it fails to rescue both synaptogenesis and axon pathfinding. These results strongly suggest that Frazzled regulates both synaptogenesis and axon pathfinding in the GFs and is necessary for synaptogenesis of the mixed electrochemical GF synapse. Our results provide novel insights into the molecular mechanisms governing neural circuit assembly and highlight Frazzled as a key player in axon guidance and synaptic development.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014310
- Subject Headings
- Drosophila, Synapses, Gap Junctions, Receptors, Cell Surface
- Format
- Document (PDF)
- Title
- TOPOLOGICAL DATA ANALYSIS FOR DATA SCIENCE: THE DELAUNAY-RIPS COMPLEX, TRIANGULATION STABILITIES, AND PROTEIN STABILITY PREDICTIONS.
- Creator
- Mishra, Amish, Motta, Francis, Florida Atlantic University, Department of Mathematical Sciences, Charles E. Schmidt College of Science
- Abstract/Description
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Topological Data Analysis (TDA) is a relatively new field of research that utilizes topological notions to extract discriminating features from data. Within TDA, persistent homology (PH) is a robust method to compute multi-dimensional geometric and topological features of a dataset. Because these features are often stable under certain perturbations of the underlying data, are often discriminating, and can be used for visualization of structure in high-dimensional data and in statistical and...
Show moreTopological Data Analysis (TDA) is a relatively new field of research that utilizes topological notions to extract discriminating features from data. Within TDA, persistent homology (PH) is a robust method to compute multi-dimensional geometric and topological features of a dataset. Because these features are often stable under certain perturbations of the underlying data, are often discriminating, and can be used for visualization of structure in high-dimensional data and in statistical and machine learning modeling, PH has attracted the interest of researchers across scientific disciplines and in many industry applications. However, computational costs may present challenges to effectively using PH in certain data contexts, and theoretical stability results may not hold in practice. In this dissertation, we develop an algorithm that can reduce the computation burden of computing persistent homology on point cloud data. Naming it Delaunay-Rips (DR), we define, implement, and empirically test this computationally tractable simplicial complex construction for computing persistent homology of Euclidean point cloud data. We demonstrate the practical robustness of DR for persistent homology in comparison with other simplical complexes in machine learning applications such as predicting sleep state from patient heart rate. To justify the theoretical stability of DR, we prove the stability of the Delaunay triangulation of a pointcloud P under perturbations of the points of P. Specifically, we impose a notion of genericity on the points of P to ensure stability. In the final chapter, we contribute to the field of computational biology by taking a data-driven approach to learn topological features of designed proteins from their persistence diagrams. We find correlations between the learned topological features and biochemical features to investigate how protein structure relates to features identified by subject-matter experts. We train several machine learning models to assess the performance of incorporating topological features into training with biochemical features. Using cover-tree differencing via entropy reduction (CDER), we identify distinguishing regions of the persistence diagrams of stable/unstable proteins. More notably, we find statistically significant improvement in classification performance (in terms of average precision score) for certain designed secondary structure topologies.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014311
- Subject Headings
- Data Science, Data Analysis, Topology--Data processing, Protein Stability
- Format
- Document (PDF)
- Title
- Synthesis and Biological Evaluation of β-hairpin Peptides as Covalent Inhibitors of the PD-1/PD-L1 Immune Checkpoint.
- Creator
- Naylon, Sarah, Roche, Stephane, Florida Atlantic University, Department of Chemistry and Biochemistry, Charles E. Schmidt College of Science
- Abstract/Description
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Protein─protein interactions (PPIs) are essential for cell─cell interactions and cellular signal transduction, which play a crucial role in various human diseases. PPIs involved in cancer immunology pathways, known as immune checkpoints, have been intensely studied, leading to a new approach to cancer therapy. The PD1:PDL1 interaction is one of the most essential immune checkpoints. Studies on PD1:PDL1 showed over ten clinical monoclonal antibodies (mAb) used to treat cancer patients....
Show moreProtein─protein interactions (PPIs) are essential for cell─cell interactions and cellular signal transduction, which play a crucial role in various human diseases. PPIs involved in cancer immunology pathways, known as immune checkpoints, have been intensely studied, leading to a new approach to cancer therapy. The PD1:PDL1 interaction is one of the most essential immune checkpoints. Studies on PD1:PDL1 showed over ten clinical monoclonal antibodies (mAb) used to treat cancer patients. Unfortunately, antibodies do not penetrate the tumor microenvironment well, and clearance from the body is slow, leading to unwanted side effects. There is a significant gap in the drug market between the typical Rule of 5 (Ro5) small-molecule drugs (MW<0.5 kDa, SASA ~150 Å) and large antibodies with molecular weights greater than 40 kDa (SASA >2,000 Å). PPIs remain challenging to modulate by small molecules due to their large, shallow, often dynamic, and water-exposed surfaces lacking well-defined binding pockets. Thus, our lab was drawn to work on large β-hairpin peptides (2-3 kDa) that can potentially mimic the CDR-H3 loops of some of the most potent and clinical anti-PD1 antibodies. Exploration of these β-hairpin peptides provided valuable insights into their folding stability, conformational flexibility, passive membrane permeability, and protein-protein interaction (PPI) blocking activities. Additionally, the rational design of TCIs against PD1, specifically targeting a lysine residue, emerged as a strategy to irreversibly obstruct the PD1:PDL1 protein-protein interaction enhancing potency of the non-covalent inhibitors by taking advantage of their specificity. Meticulous structural analysis, peptide synthesis, and biological evaluations are presented contributing comprehensions into covalent inhibitor development of drugs fbRo5.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014353
- Subject Headings
- Cancer--Immunological aspects, Protein-protein interactions, Antibodies, Monoclonal
- Format
- Document (PDF)
- Title
- MICROPLASTICS IN MANGROVE AND BEACH SEDIMENTS ON SOUTHEAST FLORIDA BARRIER ISLANDS.
- Creator
- O’Brien, Kayla Shae, Briggs, Tiffany Roberts, Florida Atlantic University, Department of Geosciences, Charles E. Schmidt College of Science
- Abstract/Description
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Plastic pollution in the marine environment is a global occurrence. Microplastics have been documented in numerous marine systems and organisms. Coastal estuaries and beach systems are at high risk for microplastic pollution. The distribution, abundance, and hazards microplastics present in these marine environments is not fully understood but are widely recognized as needed to support efforts aiming to protect and enhance these extremely valuable marine systems. This project aimed to...
Show morePlastic pollution in the marine environment is a global occurrence. Microplastics have been documented in numerous marine systems and organisms. Coastal estuaries and beach systems are at high risk for microplastic pollution. The distribution, abundance, and hazards microplastics present in these marine environments is not fully understood but are widely recognized as needed to support efforts aiming to protect and enhance these extremely valuable marine systems. This project aimed to quantify the abundance and variation of microplastics in estuarine mangrove and open coast beach sediments on Southeast Florida barrier islands, which are vulnerable and important coastal ecosystems. Barrier islands serve as a buffer between Florida’s wetland environments, reefs, and other marine habitats and may serve as a conduit or temporary sink for microplastics entering the ocean. The microplastic pollution present in estuarine mangrove and open coast beach systems may also elucidate patterns of microplastic pollution in the surrounding or similar coastal environments. There have been no extensive studies or monitoring efforts evaluating microplastics in Southeast Florida barrier islands sediments, nor comparing geomorphic properties of an area on microplastic accumulation. Study sites included back barrier estuarine mangroves and open coast beaches at three regionally similar but geomorphically distinct study sites throughout Palm Beach County, Florida. The sites were sampled seasonally in 2022 (i.e., summer and winter) to quantify the spatiotemporal distribution of microplastics.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014354
- Subject Headings
- Microplastics, Microplastics--Environmental aspects, Mangrove, Coastal sediments
- Format
- Document (PDF)
- Title
- PREFERENCE FOR NORMATIVE AND INFORMATIONAL SOCIAL INFLUENCE IN EVALUATION OF ACADEMIC INTEGRITY VIOLATION APPEALS.
- Creator
- Olson, Lauren, Nowak, Andrzej, Florida Atlantic University, Department of Psychology, Charles E. Schmidt College of Science
- Abstract/Description
-
Social influence is sought to distribute information processing for decision-making when data is limited. Undergraduate students selected information with normative or informational wording to supplement a fabricated academic integrity appeal from their university and decided whether to affirm the charge. A novel measure, the Adaptive Scale of Preference for Normative Versus Informational Social Influence (ASPNVISI), was piloted in comparison with a Polish scale of influence preference,...
Show moreSocial influence is sought to distribute information processing for decision-making when data is limited. Undergraduate students selected information with normative or informational wording to supplement a fabricated academic integrity appeal from their university and decided whether to affirm the charge. A novel measure, the Adaptive Scale of Preference for Normative Versus Informational Social Influence (ASPNVISI), was piloted in comparison with a Polish scale of influence preference, individual difference measures in motivation (e.g., Need for Closure), and behavioral measures of influence-seeking. Results did not support the hypotheses that psychological needs would predict behavioral social influence preferences, though Need for Cognition and Need to Belong predicted self-reported preferences. The ASPNVISI was correlated with the existing scale of influence preference, providing support for its continued development. Contrary to the hypothesis, confidence in the decision on a charge of academic dishonesty was not related to selected influence; race and conservatism were related to confidence, and gender to the selections. Next steps include further pilot testing of the ASPNVISI and expansion of the behavioral task.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014333
- Subject Headings
- Social influence, Decision making, Social psychology
- Format
- Document (PDF)
- Title
- LONG-TERM NATIONAL & REGIONAL BEACH NOURISHMENT TRENDS & DRIVERS: IMPLICATIONS FOR COASTAL RESILIENCE.
- Creator
- Palaparthi, Jyothirmayi, Briggs, Tiffany Roberts, Florida Atlantic University, Department of Geosciences, Charles E. Schmidt College of Science
- Abstract/Description
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With the escalating challenges posed by global warming, sea-level rise, and natural disasters like hurricanes and tropical storms, coastal erosion has become a critical issue along the US coasts. The economic significance of U.S. coastlines, multitude of services offered by these coastal areas, underscores the critical importance of addressing the threats posed by both natural and human-induced factors that lead to erosion and coastal loss. To enhance future planning and to promote resilience...
Show moreWith the escalating challenges posed by global warming, sea-level rise, and natural disasters like hurricanes and tropical storms, coastal erosion has become a critical issue along the US coasts. The economic significance of U.S. coastlines, multitude of services offered by these coastal areas, underscores the critical importance of addressing the threats posed by both natural and human-induced factors that lead to erosion and coastal loss. To enhance future planning and to promote resilience of these invaluable coastal resources, it is essential to gain a comprehensive understanding of the strategies employed to mitigate coastal erosion in response to the diverse array of driving forces. A widely embraced solution to this erosion, caused by both natural forces and human activities, is beach nourishment. Historical assessments of beach nourishment at the regional level have been conducted, however, there remains a gap in national-level analysis examining the overarching trends and the diverse factors that impact these trends. This study aims to provide a comprehensive perspective on beach nourishment practices encompassing 16 coastal states, including the top ten highly nourished states, and an additional six states selected from various coastal regions. It delves into the multifaceted factors that shape these practices, offering a holistic understanding of the beach nourishment landscape at a national level. An extensive analysis of beach nourishment trends and the influence of factors such as sea level rise, storms, hurricanes, hurricane categories, and coastal management approval years on beach nourishment activities was conducted.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014309
- Subject Headings
- Beach nourishment, Coastal zone management
- Format
- Document (PDF)
- Title
- PRION FRAGMENT 106-128: AN INVESTIGATION OF AMYLOID FORMATION AND INHIBITION.
- Creator
- Regmi, Deepika, Du, Deguo, Florida Atlantic University, Department of Chemistry and Biochemistry, Charles E. Schmidt College of Science
- Abstract/Description
-
Misfolding and aggregation of Cellular Prion Protein (PrPc) is a major molecular process involved in the pathogenesis of Prion diseases. An N-terminal portion of the Prion protein, PrP106-128, is a 23-residue peptide fragment characterized by an amphipathic structure with two domains: a hydrophilic N-terminal domain and a hydrophobic C-terminal domain. Here, we studied the aggregation properties of the prion fragment peptide PrP106-128. The results show that the peptide aggregates in a...
Show moreMisfolding and aggregation of Cellular Prion Protein (PrPc) is a major molecular process involved in the pathogenesis of Prion diseases. An N-terminal portion of the Prion protein, PrP106-128, is a 23-residue peptide fragment characterized by an amphipathic structure with two domains: a hydrophilic N-terminal domain and a hydrophobic C-terminal domain. Here, we studied the aggregation properties of the prion fragment peptide PrP106-128. The results show that the peptide aggregates in a concentration-dependent manner in an aqueous solution and that the aggregation is sensitive to pH and the preformed amyloid seeds.Furthermore, we show that the zwitterionic POPC liposomes moderately inhibit the aggregation of PrP(106–128), whereas POPC/cholesterol (8:2) vesicles facilitate peptide aggregation likely due to the increase of the lipid packing order and membrane rigidity in the presence of cholesterol. In addition, anionic lipid vesicles of POPG and POPG/cholesterol above a certain concentration accelerate the aggregation of the peptide remarkably. The strong electrostatic interactions between the N-terminal region of the peptide and POPG may constrain the conformational plasticity of the peptide, preventing insertion of the peptide into the inner side of the membrane and thus promoting fibrillation on the membrane surface. The results suggest that the charge properties of the membrane, the composition of the liposomes, and the rigidity of lipid packing are critical in determining peptide adsorption on the membrane surface and the efficiency of the membrane in catalyzing peptide oligomeric nucleation and amyloid formation.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014356
- Subject Headings
- Prion Proteins, Prion diseases, Epigallocatechin gallate, Amyloid
- Format
- Document (PDF)
- Title
- ARE SOUTH FLORIDA’S GOPHER TORTOISE POPULATION’S GENETICALLY DIFFERENTIATED FROM EACH OTHER?.
- Creator
- Rothberg, Olivia, Frazier, Evelyn, Hughes, Colin, Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
- Abstract/Description
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Gopher Tortoises are an imperiled terrestrial tortoise considered ecosystem engineers, as their burrows support over 350 species of “commensals”. Due to extensive anthropogenic habitat destruction and fragmentation, tortoise populations have significantly declined over the past 100 years. This isolation is leading to a premature loss of genetic variation, further precipitating the decline of this species. Understanding the genetic structure of this species can aid management decisions through...
Show moreGopher Tortoises are an imperiled terrestrial tortoise considered ecosystem engineers, as their burrows support over 350 species of “commensals”. Due to extensive anthropogenic habitat destruction and fragmentation, tortoise populations have significantly declined over the past 100 years. This isolation is leading to a premature loss of genetic variation, further precipitating the decline of this species. Understanding the genetic structure of this species can aid management decisions through intentionally relocating animals based on genetic units and historic gene flow, to preserve adaptive diversity and evolutionary potential on a large scale. I investigated whether Southeast Florida has a genetically distinct subpopulation of Gopher Tortoises in the unexamined southeasternmost extent of their range, from Palm Beach to Miami-Dade counties, using 9 microsatellite loci previously characterized for this species (Schwartz et al 2003) and found that our populations are only modestly differentiated from each other, and have greater genetic diversity than other populations.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014362
- Subject Headings
- Gopher tortoises, Florida, South, Population genetics
- Format
- Document (PDF)
- Title
- DISSECTING THE MECHANISTIC ROLES OF REGULATORS IN MEDIATING AMYLOID-BETA AMYLOIDOGENESIS.
- Creator
- Shen, Fengyun, Du, Deguo, Florida Atlantic University, Department of Chemistry and Biochemistry, Charles E. Schmidt College of Science
- Abstract/Description
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Alzheimer’s disease (AD) is a common neurodegenerative disorder. The most recognized disease pathology is the Amyloid-β (Aβ) cascade hypothesis which states that the accumulation of Aβ plaques might be the cause of AD. In the AD brain, Aβ plaques stockpile a variety of molecular components including metals, lipids, nucleic acids, carbohydrates, and peptides, indicating Aβ aggregation might be influenced by these modulators. In this dissertation, we investigated the effects of Zn2+ and...
Show moreAlzheimer’s disease (AD) is a common neurodegenerative disorder. The most recognized disease pathology is the Amyloid-β (Aβ) cascade hypothesis which states that the accumulation of Aβ plaques might be the cause of AD. In the AD brain, Aβ plaques stockpile a variety of molecular components including metals, lipids, nucleic acids, carbohydrates, and peptides, indicating Aβ aggregation might be influenced by these modulators. In this dissertation, we investigated the effects of Zn2+ and carnosine, phospholipids, and β-hairpins on Aβ aggregation to dissect their mechanistic roles in the amyloidogenesis of Aβ. We first systematically studied the kinetic impact of Zn2+ on the aggregation of Aβ40 and Aβ40-M. Our results show that the presence of Zn2+ transforms the Aβ40 aggregation kinetics from a single sigmoidal to a biphasic process, while the aggregation of Aβ40-M is significantly suppressed by Zn2+. We also found that a nature dipeptide, carnosine, remarkably decreases the activity of Zn2+ on modulating Aβ aggregation, although it has a weak direct effect on the peptide aggregation kinetics. Second, we investigated the activities of Aβ40 and Aβ42 in inducing membrane damage and the effects of lipid membranes on the aggregation of these peptides using liposome models containing mitochondrial-specific phospholipid–cardiolipin (CL).
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014314
- Subject Headings
- Alzheimer's disease, Amyloid beta-Peptides, Neurodegenerative Diseases
- Format
- Document (PDF)
- Title
- Dscam1 Regulates Synapse Formation and Function in the Giant Fiber System of Drosophila.
- Creator
- Spencer, Casey L., Murphey, Rodney, Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
- Abstract/Description
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Proper formation of synapses in the developing nervous system is critical to the expected function and behavior of an adult organism. Neurons must project neurites, in the form of axons or dendrites, to target areas to complete synaptic circuits. The biochemical tool that cells use to interact with the external environment and direct the guidance of developing neurites are guidance receptors. One such guidance receptor that is extensively studied to uncover its roles in developmental...
Show moreProper formation of synapses in the developing nervous system is critical to the expected function and behavior of an adult organism. Neurons must project neurites, in the form of axons or dendrites, to target areas to complete synaptic circuits. The biochemical tool that cells use to interact with the external environment and direct the guidance of developing neurites are guidance receptors. One such guidance receptor that is extensively studied to uncover its roles in developmental disorders and disease is DSCAM (Down-Syndrome Cell Adhesion Molecule). To better understand the role of DSCAM in humans, a fly homolog Dscam1 was extensively characterized in the giant fiber system (GFS) of Drosophila to further explore its roles in axon guidance, synapse formation, and synapse function. The UAS-Gal4 system was used to alter the protein levels of Dscam1 within the giant fiber interneurons (GFs). A UAS-RNAi construct against Dscam1 was used to knockdown translation of all possible isoforms within the GFs. A UAS-Dscam1(TM2) construct was used to overexpress a single isoform of Dscam1 that is specifically trafficked to the axons. Confocal microscopy was used to determine the morphological changes associated with dysregulated Dscam1 levels. Visualization via fluorescent markers was accomplished of both pre- and post-synaptic cells, the GFs and tergotrochanteral motorneurons (TTMns), respectively, and synapse interface was determined as colocalization of the two cells. Additionally, the functional components of the GF-TTMn synapse, both gap-junctions, and presynaptic chemical active zones were tagged via fluorescent antibodies and quantified.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014364
- Subject Headings
- Drosophila, Cell Adhesion Molecules, Nervous System, Synapses
- Format
- Document (PDF)
- Title
- ESTABLISHMENT AND APPLICATION OF WORKFLOWS FOR STRUCTURE-FUNCTION ANALYSIS OF SYNAPTIC COMPONENTS.
- Creator
- Thomas, Connon I., Kamasawa, Naomi, Murphey, Rodney, Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
- Abstract/Description
-
At the site of neuronal communication, multiple interacting components drive synapse structure and function. Synaptic vesicle pools, membrane proteins, mitochondria, and perisynaptic astrocyte processes (PAPs) are all structures that can be altered through naturally occurring plasticity mechanisms to modulate neurotransmission, and disruption of these structures can result in synapse dysfunction and disease. Due to the minute size of the synapse, electron microscopy (EM) remains the gold...
Show moreAt the site of neuronal communication, multiple interacting components drive synapse structure and function. Synaptic vesicle pools, membrane proteins, mitochondria, and perisynaptic astrocyte processes (PAPs) are all structures that can be altered through naturally occurring plasticity mechanisms to modulate neurotransmission, and disruption of these structures can result in synapse dysfunction and disease. Due to the minute size of the synapse, electron microscopy (EM) remains the gold standard for ultrastructural characterization; however, due to the complexity of EM datasets, extraction of information has become a bottleneck which places limits on the amount of data that can be collected and analyzed. A need exists for easy-to-use workflows that automate and enhance analysis throughput, to keep up with the streams of image data that are able to be produced. Here, I develop the use of AI algorithms, correlative microscopy techniques, and novel structural analysis methods to characterize postsynaptic mitochondria, PAPs, synaptic vesicles, and integral membrane proteins and their impact on synapse structure and function. I show that both postsynaptic mitochondria and PAPs in the visual cortex are positioned to support synapse structure and function; cleavage of a synaptic adhesion molecule affects synaptic vesicle accumulation in the amygdala; and presynaptic voltage gated calcium channels aggregate near active zone machinery in the brainstem. In addition, I highlight the use of virtual reality as a fast and intuitive tool for the identification and isolation of individual neurites in 3D EM. Thus, my work establishes novel technical approaches for EM and advances our understanding of neuronal communication through original research of several synaptic components.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014315
- Subject Headings
- Synapses, Artificial intelligence, Astrocytes
- Format
- Document (PDF)
- Title
- EFFECTIVENESS OF MEMES PREDICTED BY MORAL CONTENT AND AFFECTIVE POLARIZATION.
- Creator
- Thompson, Jordan L., Wetherell, Geoffrey, Florida Atlantic University, Department of Psychology, Charles E. Schmidt College of Science
- Abstract/Description
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Memes have become a staple in political communication. However, the relationship between individuals’ political orientation, their level of affective polarization, the moral content of memes, and meme effectiveness is underexplored. I expected that polarized partisans would rate ingroup memes as more effective than outgroup memes. In line with moral foundations theory, I expected that polarized liberals would rate individualizing foundation memes as more effective than less polarized memes...
Show moreMemes have become a staple in political communication. However, the relationship between individuals’ political orientation, their level of affective polarization, the moral content of memes, and meme effectiveness is underexplored. I expected that polarized partisans would rate ingroup memes as more effective than outgroup memes. In line with moral foundations theory, I expected that polarized liberals would rate individualizing foundation memes as more effective than less polarized memes and that polarized conservatives would rate binding foundation memes as more effective than less polarized conservatives. Participants (N = 467) rated moral political memes for meme effectiveness. Results indicated that more polarized conservatives, but not liberals, rated ingroup memes as more effective than outgroup memes. Polarized liberals rated purity/sanctity as more effective than less polarized liberals. Polarized conservatives rated fairness/reciprocity plus the binding foundations memes as more effective than less polarized conservatives. These results indicate that polarized partisans react to memes differently.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014316
- Subject Headings
- Memes, Political communication, Social psychology
- Format
- Document (PDF)