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Caribbean Amphipod Diversity in Panama
No full textGlobally, there are about 10,000 species of amphipods, a relatively unnoticed order of crustaceans. Amphipods range in size from 1-340 mm in length, but are typically no longer than 15 mm. Given the incredible diversity and small size of amphipods, it can be difficult to identify species correctly. This preliminary analysis of the Caribbean amphipods of Bocas del Toro, Panama involved the collection of amphipods via scuba diving and collection of invertebrate hosts, coral rubble, and sediments. Amphipods were rough sorted by appearance; each morpho-species was imaged in multiple planes of focus using a macro rail system; and finally identified to species level through the use of numerous taxonomic keys. The results will include a species list and an interactive online identification key, highlighting the major characteristics that differentiate species from each other. By increasing the taxonomic knowledge of marine species in Panama, we will gain a better understanding of the biodiversity of the area. With a comprehensive species list and identification tools, scientists and lay people will be able to identify species and monitor changes to the environment that will be evidenced by changing species assemblages. Understanding amphipod diversity is particularly important as amphipods are often used as bioindicators of the health of their environment. The discovery or absence of certain species in an area can be an indicator of changes in water quality or niche availability
USING THE EMBL-EBI CLUSTAL OMEGA TOOL TO CALCULATE DIVERSITY OF HEAVY CHAIN PHAGE-DISPLAY LIBRARIES
Get PDFHere we show that traditional Sanger sequencing combined with analysis tools available from the European Molecular Biology Laboratory-European Bioinformatics Institute (EMBL-EBI), specifically EMBOSS Transeq and Clustal Omega, is extremely effective in the analysis of naïve phage display antibody libraries for the determination of library size and diversity. The free tools are easy to use and require little manipulation of reads by hand, allowing analysis to be performed on a standard personal computer. Utilization of this technique has applicability to researchers with limited access to deep sequencing. The primary drawback to this analysis methodology is that antibodies with particular molecular or binding properties, desirable or otherwise, are not identifiable by their sequences
SYNTHESIS AND TESTING OF PENICILLIN DERIVATIVES: AN INTERDISCIPLINARY PROJECT
No full textUndergraduate research students embarked on an interdisciplinary project that simulated real-world research. The students did extensive research into the history, structure, synthesis and mechanism of penicillin and its derivatives. Each student chose to synthesize a different derivative based on their research findings. After synthesis, the compounds were given to the microbiology students for analysis of their antibiotic properties. Penicillins belong to the b-lactam class of antibiotics and are used to treat both Gram-negative and Gram-positive bacteria. Penicillins all have a common backbone and a changeable side chain group. The basic structure of penicillin can be purchased and the side chains can be added easily using chemical reactions and techniques learned in organic chemistry. The students prepared penicillin derivatives using the following side chains: phenoxyacetyl chloride, 1-napththolyl chloride, and benzoyl chloride. The synthesis and work-up took three hours. The samples were then tested for activity against penicillin, purchased through Carolina Biological, to determine their antibiotic properties. The results of the synthesis and analysis of the derivatives is presented in this poster. This project is a great way to expose students to the drug-discovery and research process. The students involved in this research were freshman and sophomores. This was their first time doing scientific research and drug synthesis. The students doing the microbiology analysis were seniors. This was a great learning project for all students and facilitates critically-thinking skills that a normal laboratory course would not provide
PATTERNS OF BIOTIC AND ABIOTIC CONTAMINATION WITHIN A SMALL WATERSHED IN NORTHEAST GEORGIA
No full textThe Hazel Creek Watershed is a small drainage (\u3c100 km2) just west of the Eastern Continental divide in Habersham County, Georgia. The drainage is home to over 600,000 chickens, as well as other types of agriculture, and includes the main campus of Piedmont University in Demorest, GA. Water contamination due to agriculture and land development are a concern for this watershed, which is a part of the larger Soque River and Chattahoochee River Watersheds. We wanted to know whether there was a specific issue with biotic and abiotic contamination in this watershed, whether that contamination was affected by rain events, and whether specific portions of the watershed contributed disproportionately to these issues. We found a consistent relationship between area drained and biotic contamination (with E. coli bacteria) within the watershed after rain events. Two sites were found to have higher than expected levels of bacteria, based on area drained. One of those sites is on Piedmont University’s campus, just below some restored wetlands that support a thriving beaver population. Abiotic contamination (measured by conductivity) decreased with area drained. While the University’s wetlands may be contributing to biotic contamination, conductivity decreased from the upstream to the downstream end
ANALYZING THE SHARK PALEOECOLOGY OF COASTAL GEORGIA FROM THE MIOCENE AND PLIOCENE EPOCHS
No full textShark paleoecology is a subject matter that often yields indecisive conclusions based on the limited fossilization of their anatomical structures, with the exception of their teeth. The majority of the Atlantic coast has been studied regarding the presence of certain prehistoric shark species from the Miocene, Pliocene, and Pleistocene epochs. However, the information pertaining to the Georgia coast seems relatively understudied, leaving room for the analysis of its potential community structure during this time. A study was conducted in which thousands of fossil shark specimens and subsequent marine fauna were collected from dredge spoils created by the US Army Corps of Engineers (USACE): Savannah District. A total of 5,127 fossil shark teeth were collected, of which 4,981 were identified. Twenty-three potential species are believed to be included in this assemblage. Additional research conducted by the U.S. Geological Survey in 2001 shed light on the fossil formations beneath Brunswick, including their specific depths below sea level. Communication with the USACE detailed their annual dredging depths of 36, 38, and 41 feet below the Mean Lower Low Water (MLLW). Combining this information with the known life histories of each of the 23 species of prehistoric sharks, it was determined that all specimens coexisted during a time period from the late Miocene to early Pliocene (8.0-3.0 Ma) and being preserved in the Ebenezer Member 5 formation. Further research regarding the ecological roles of all identified shark species can create an even more precise look into the community structure of coastal Georgia during the late Miocene and early Pliocene
Milankovitch Cycles for Potential Earth-analogs in Alpha Cen AB
No full textThe axial tilt of an Earthlike world influences its yearly-averaged radiative flux can vary for a given latitude. Such variations were realized nearly a century ago through Milankovitch Cycles that describe the frequency and extent of Earth’s ice ages in response to the orbital evolution of the solar system. We examine the global ice distribution for Earthlike worlds in Alpha Centauri AB (and similar binaries) and how such worlds would experience Milankovitch Cycles induced by orbital perturbations from a stellar binary using an energy balance climate model that incorporates ice growth and retreat. An Earth-analog whose orbit is inclined relative to the binary plane can transition between several global ice distribution states similar to Milankovitch Cycles, but there is also a risk for runaway glaciation when ice forms at both poles and the equator. This risk depends on the initial planetary orbit, obliquity, spin precession, binary orbit, and the luminosity of the host star. We conclude that the potential habitability of planets in binary systems require more than an estimation of the radiative flux as determined by previous studies due to the complex gravitational interactions
Test of Predator Avoidance by Larvae of the Blue Ridge Two-lined Salamander (Eurycea wilderae) in Appalachian Streams
No full textPredator avoidance is an important ecological interaction in many communities, enabling prey organisms to avoid potential negative impacts on population structure and fitness. Larval Blue Ridge Two-lined salamanders (Eurycea wilderae) are extremely abundant components of Appalachian streams and fall prey to many types of predators. In order to test the hypothesis that larval E. wilderae actively avoid important predators, we paired them against a variety of predators: Banded Sculpin (Cottus carolinae), Chattahoochee Crayfish (Cambarus howardi), and Spring Salamanders (Gyrinophilus porphyriticus), both adult and larval. We collected Eurycea larvae, crayfish, and Gyrinophilus larvae from a fishless tributary of Hazel Creek, Demorest, Habersham County, Georgia. We collected sculpins from a different, nearby tributary of Hazel Creek. We collected Gyrinophilus adults from Sosebee Cove, Union County, Georgia. We placed each predator in an aerated cage (9.5 x 8.5 x 10 cm) at one end of a 1-m metal trough. A control treatment consisted of an aerated cage without a predator. For each trial, we placed a Eurycea larva in the middle of the trough and observed it every 10 min until the point at which the larva had not moved between two observations. We then measured the distance between the larva and the cage. We ran 18‒20 replicates for each of the five treatments with no larva used more than once. Following trials, we released the larvae and predators back into their respective streams. We used ANOVA to test for differences in mean distance among treatments. We found no significant differences (F4,93 =0.470; P = 0.758). Because of their high densities, perhaps larval E. wilderae do not suffer sufficient predatory pressure from a particular predator to evolve appropriate behavioral responses
ANNOTATION OF THE lin-28 GENE ACROSS THREE SPECIES OF DROSOPHILA**
No full textThe primary goal of the Pathways Project of the Genomics Education Partnership is to determine the evolution of the regulatory regions of the 64 genes in the insulin-signaling pathway across 28 Drosophila species. The insulin-signaling pathway is important because it regulates how sugars are processed and contributes to the growth and development of animals. This project will identify, annotate, and build gene models for the lin-28 gene in three species at various evolutionary distances from D. melanogaster: D. simulans, D. biarmipes, and D. willistoni. The lin-28 gene encodes a protein that regulates developmental timing and positively regulates the insulin-like receptor signaling pathway. These gene models and many others will allow the Pathways Project consortium to locate gene regulatory regions and compare them across the Drosophila genus. Additionally, we will assess the conservation among the three species of the genomic neighborhood, gene structure, and amino acid sequences of the gene products. Progress to date includes the complete annotation of the gene models of the D. biarmipes and D. willistoni species, while the D. simulans model still needs to be completed. Results indicate that the genomic neighborhood and overall gene structure are well conserved for both the D. biarmipes and D. willistoni species compared to D. melanogaster, and the amino acid sequence divergence corresponds to their phylogenetic distance from D. melanogaster
ASSESSING THE ANTIMICROBIAL ACTIVITY OF LEMON AND LEMONGRASS ESSENTIAL OILS AGAINST COMMON MICROBES FOUND IN SKIN INFECTIONS
No full textThis research assessed the antimicrobial properties of lemon and lemongrass essential oils against the common skin microbes: Corynebacterium xerosis, Staphylococcus aureus, Staphylococcus epidermidis, and the fungus Candida albicans. Disk diffusion assays using 2 μl of the oil or DMSO control were done on Mueller Hinton agar (bacteria) or Sabouraud agar (fungus). Minimum Inhibitory Concentration (MIC) assays were performed using the oil and the corresponding broth media. The MIC was the lowest concentration of oil that significantly inhibited growth compared to the no oil control. Minimum bacteriocidal concentration (MBC) assays were performed by plating microbes from the broth containing the potential MIC on an agar plate, growing overnight and checking for growth. One-way ANOVA and post hoc Tukey test were used to determine the statistical significance of all results obtained. There were no zones of inhibition when lemon essential oil and control DMSO were tested against any of the selected microbes. Average lemongrass zones of inhibition were 25mm + 4.08 for C. albicans (P\u3c0.001), 13mm + 1.62 for C. xerosis (P\u3c0.001), 8mm + 5.04 for S. aureus (P\u3c0.05), and 26mm + 6.35 for S. epidermidis (P\u3c0.001). Lemon oil MICs were 6.25% (p\u3c0.01) for C. albicans and 25% (p\u3c0.05) for S. aureus. Lemongrass oil MICs were 1.56% (p\u3c0.01) for C. albicans, 1.56% (p\u3c0.05) for S. aureus, and 3.125% (p\u3c0.01) for S. epidermidis. No MICs were found for C. xerosis. There were no MBCs found for lemon oil. The MBCs for lemongrass oil was 1.56% for C. albicans and 6.25% for S. aureus. With the continuously expanding knowledge of essential oils, they may be soon considered a viable, holistic option to treating infections
Synthesis, Characterization, and Bioactivity of 3-Substituted Coumarins as an Undergraduate Project
Get PDFCoumarins are an important class of phytochemicals, a chemical defense presumed to be secreted by plants. More recently, Coumarins have gathered popularity for their basis in anti-cancer agents. This paper dives into the organic synthesis of two 3-substituted coumarins from o-vanillin using the Knoevenagel condensation reaction. The 3-substituted coumarin were characterized using melting point analysis, 1H-NMR, and UV-Vis spectroscopy. In addition, the anticancer activity of synthesized 3-substituted coumarin compounds were assayed against topoisomeraseIIα, which is the target enzyme of FDA approved anti-cancer drug etoposide since it is an active enzyme in cancer cell replication. The demonstrated procedures can be used as an undergraduate senior project that traverses through several classes that chemistry majors take