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THE EFFECTS OF SIZE AND MIGRATORY STATUS ON AVIAN SPECIMEN PRESERVATION VIA LYOPHILIZATION
No full textPreserved animal specimens are important learning tools for biology students. Unfortunately, creating a teaching collection by traditional means such as skinning and stuffing is time-consuming and requires a great deal of expertise. Freeze-drying animal specimens is much quicker and easier to learn than other methods. In our study, we investigated whether the size or migratory status of avian specimens impacted their ability to freeze-dry. A successful freeze-dry attempt was determined by a lack of foul odor and substantial weight loss. Our birds were donated by Birds Georgia, Project Safe Flight which collects birds that died due to collisions with skyscrapers in the Atlanta, Georgia area. We preserved 208 birds via freeze-drying, 190 of which were deemed successful. Initial specimen condition had the greatest impact on successful preservation. Body mass of our specimens ranged from 1.3g – 162g and overall, specimens lost between 18-80% of their initial body weight. Within these birds, we found no correlation between the initial mass of the bird and successful preservation. We have not, however, examined the preservation of larger birds using freeze-drying. We did discover that the migratory status of the bird had an impact on successful freeze-drying. Through migrants (birds that traveled through the Atlanta area during the fall and spring) lost significantly less weight than birds who only breed in Georgia, those that only spend winter here, or those that reside here year-round. Overall, we found that while avian specimen size (for small and medium birds) was not correlated to freeze-dry success, the migratory category did have an impact
UTILIZING A NEW COASTAL MARINE FIELD SAMPLING TECHNIQUE FOR MARK-RECAPTURE ON THE GULF PIPEFISH, SYNGNATHUS SCOVELLI**
No full textConcentric circular plots are widely used in terrestrial ecology but are rarely applied to marine environments. This sampling technique partnered with a mark-recapture study has the potential to identify small scale habitat usage and movement patterns, site fidelity, and population estimation. We tested this methodology on the Gulf pipefish, Syngnathus scovelli, that is an excellent flagship species for monitoring the health of submerged aquatic vegetation and lack current management policies. Two sites were selected within a continuous seagrass bed in Tampa Bay and each site consisted of 4 concentric 1.5 m circular plots (20 m diameter). We conducted a mark-resight during wet season in August 2022 and a mark-recapture during dry season in February 2023 to estimate the population surrounding our sites and to identify Gulf pipefish movement within the sites. In August, a total of 2,125 pipefish per 829.36 m2 were collected, 803 fish were marked, and at most 213 of the marked fish were recaptured (26.5%). There was a 4.8-day average interval between mark and recapture events. Of those recaptured, 57.3% were found within 5 m of their center release point suggesting possible site fidelity. In February, a total of 187 pipefish were marked per 829.36 m2 and 5 of the fish were recaptured (2.7%) across a 4.4-day average interval. Program Mark models and the lack of multiple recaptures indicate the Gulf pipefish were transient and do not have site fidelity in February. Based on this study, the methodology is repeatable, and it can assess a species’ habitat usage and movement patterns within their coastal marine environment. Results indicate that the Gulf pipefish seasonally change how they use their environment. Monitoring flagship species, like Gulf pipefish, with this novel coastal methodology can elucidate fine scale changes in habitat usage which is crucial for implementing and monitoring management policies
DIVERSITY OF PANAMANIAN AMPHIPODS (CRUSTACEA) WITHIN THE PARVORDER HADZIIDIRA
No full textAmphipods are a successful order of Crustaceans that inhabit a wide range of environments. Ecosystem services provided by amphipods include nutrient cycling, environmental bioindication, and being an important food source. In Panama, amphipods are understudied, despite the Caribbean being typically well-studied for biodiversity. Amphipods belonging to the parvorder Hadziidira include 1159 species worldwide, yet none have been documented in Panama. The parvorder is divided into 14 families, including amphipods that are typically associated with sponges, coral rubble, or algae. Based on the diversity of hadziidiran amphipods, we hypothesized that there is a high number of amphipods belonging to the parvorder Hadziidira in Panama. Collections from 2005, 2021, and 2023 have revealed 26 species in six hadziidiran families from Bocas del Toro, Panama, which are all new records for the area. The species are described morphologically using light microscopy for analysis and illustration. Important characters are discussed for identification of particularly difficult genera within the parvorder. Outside of Panamanian studies, this research contributes to the broader field of amphipod research by contributing to information on the phylogeny and clarification on the classification of different amphipod species
SYNTHESIS AND PERFORMANCE TESTS OF MESH-INTEGRATED HYDROGELS**
No full textHydrogels are typically defined as hydrophilic, colloidal gels consisting of cross-linked polymer chains that are capable of absorbing and retaining large amounts of water, ions, and small molecules. Hydrogels can maintain their structural integrity with aggressive temperature changes. Previously, hydrogels have been used to absorb contaminants and/or nutrients such as oil, urea, nitrogen and phosphorus. Hydrogels can be made out of both natural and synthetic materials, and the properties of hydrogels can be customized by modifying the polymer chains’ composition and crosslinking methods. The goal of this research is to immobilize hydrogels on meshes in order to enhance their durability and applicability. It is hypothesized that the integration of mesh into hydrogels will ensure the stability for continuous operation while providing the favored traits: increased durability and superior absorption and swelling capacities. For this study, three analogous polyacrylamide gels are immobilized atop meshes, while three other polyacrylamide hydrogels (the control group) were formed without immobilization. To determine the swelling abilities for the hydrogels, a specific amount of hydrogel samples was placed in water, and the increase in total mass was measured as a function of equilibration time. The adsorption behavior was investigated as well for the immobilized or non-mobilized hydrogels. The durability was tested by repeating the experiment with increased number of batches. The resulting performance and observations for the immobilized polyacrylamide hydrogels were systematically compared against the control group. The integration did not perform better than the control group, but the stability for repeated operation was promising with further optimization of immobilization including the materials and size of employed mesh. Future study will extend to developing continuous nutrient recycle operation. This includes investigation of the relationship between the amount and composition of polymers and their performance and synthesizing gels in 3-D structures
THE EFFECT OF CANNABINOIDS ON THE DEVELOPMENTAL MORPHOLOGY OF ZEBRAFISH**
No full textPrior results on exposure of zebrafish embryos to both Δ9-THC and Δ8-THC demonstrated delayed hatch rate, higher death rate and shorter embryos with curved spines when compared to control embryos. In this study, we also examined the effects of cannabidiol (CBD), a widely available, legal substance used as treatment for numerous ailments from relieving pain or stress to enhancing sleep. We compared the effects of treatment with CBD, Δ8-THC, and Δ9-THC to experimental controls on the embryonic development of zebrafish, Danio rerio. Embryos were randomly divided into groups receiving 0, 0.15, 0.3, 0.6, 1.25, 2.5 and 5 µg/ml of each of these cannabinoids. We monitored embryos daily to record the number of embryos that were dead or alive. We also recorded daily how many had hatched from their chorions. Embryos were allowed to develop until day four post-fertilization (4 dpf) when spinal curvature and heart rates were assessed. We then anesthetized the embryos, fixed them in 4% paraformaldehyde overnight and stored them in 100% methanol at 20° C for morphologic assessment of jaw structure using Alcian blue staining of cartilage and to examine the pattern of neural development through immunofluorescent staining. This project is ongoing, and we have yet to examine jaw structure or neural development. Initial data suggest that CBD, like Δ8-THC and Δ9-THC, promotes spinal curvature, mortality, delayed hatch rate, and decreased heart rates. Thus, exposure to CBD, like Δ9-THC and Δ8-THC, does not appear to be safe during embryo development. While we cannot extrapolate the results of this study to humans, caution may be appropriate, given the high conservation of genetics and key signaling pathways between humans and zebrafish, a model being increasingly used for developmental studies
THE EFFECTS OF VAPING LIQUID ON INTEGRITY OF TOOTH ENAMEL
No full textThe health of the oral cavity and the oral microbiome are vital to an individual’s overall health. With the growing popularity of e-cigarette use, also known as vaping, it is reasonable to explore the effects of this habit on oral health. Due to the effects of chemicals known to be harmful and to the ingredients whose effects are still unknown, an individual who uses vaping liquid either occasionally, or consistently, is potentially putting their oral health at great risk. This research aims to explore the potential effects of vaping on the health, appearance, and structural integrity of the teeth. The structure and function of the human teeth rely heavily on the state of the oral microbiota and the durability of tooth enamel. Due to the lack of regulation of ingredients found in vaping liquid and the lack of long term results due to the recent rise in the use of vaping, its effects on oral health are largely unknown. This is mainly due to the lack of regulation of ingredients in vaping liquid and the inability to gather long term results. As previously published studies conducted with smoking conventional cigarettes have shown the harmful effects of inhaling traditional cigarettes, it would be advantageous to conduct similar long-term studies on the use of vaping liquids. The possibility of long term negative effects of vaping on both the structural integrity of the teeth and the overall health of the oral cavity cannot be ignored. In this study we measured the change in mass of human teeth and the change in color, over a period of weeks of exposure to vaping liquid. The preliminary results of this ongoing study indicate that exposure to these liquids result in a loss of up to 5.04% of mass of the tooth over the course of the study. Furthermore, the results indicated that these liquids cause yellowing of the teeth
COMPUTATIONAL ANALYSIS AND EVALUATION OF BINARIZATION METHODS IN AFM IMAGES FOR INVESTIGATING POROSITY OF FLUORINE-DOPED TIN OXIDE THIN FILMS**
No full textThis study focuses particularly on a computational analysis of morphological properties for determining porosity in Fluorine-doped Tin Oxide (FTO) thin films. Analysis of porous materials plays a pivotal role in optimizing the optical, electrical, mechanical, and structural properties in optoelectronic market applications, including solar cells and gas sensors. By characterizing and controlling porosity, researchers and engineers can design and fabricate materials with enhanced performance, efficiency, and reliability for a wide range of optoelectronic devices. In this study, we quantitatively analyze key parameters in Atomic Force Microscopy Images (AFM) images of serial layered FTO using a combination of analytical software tools, namely Gwyddion and MATLAB, and employing methods such as binarization with an adaptive threshold and Monte Carlo simulations. The methodology and analytical techniques presented here facilitate a comprehensive characterization of porosity offering valuable insights into the microstructural features of the films; in particular, we denote the significance of performing such analysis on strictly morphological images obtained using an AFM. We report a mean porosity of 0.93% in singly layered FTO, however, in evaluating the porosity of serial layers of FTO thin films we may determine the efficacy of FTO films in various optoelectronic devices with pertinence to porosity; hence, the defined analytical methods represent a crucial stage in the fabrication, commercialization, and optimization of future optoelectronics
LIGHT RAYS PASSING THROUGH LIQUID CRYSTALS**
No full textAs light passes through a liquid crystal, it splits into two different rays, the ordinary ray and the extraordinary ray. The effective refractive index is a functional composed of those two rays. An attempt is made to find an explicit equation for the path of light by finding the minimum distance to pass through a given field. Using the Euler-Lagrange equation in order to minimize the effective refractive index, the resulting function is a highly nonlinear second-order ordinary differential equation. If solved, this would give the equation of light passing through a given liquid crystal according to Fermat\u27s principle of least time. The equation was examined for three different types of fields through which the light passes. A numerical solution was evaluated by computing a metric and subsequent Christoffel symbols, then applying the Euler-Lagrange equation to find a system of geodesics and graphing numerically to visualize the path of light. The Ricci curvature is computed to find how non-flat the associated geometry is, and the curvature of the path is computed to find when maximum ray bending occurs. Finally, the numerical process is repeated in three dimensions and the Gaussian curvature is computed for various fields
TRACK RECONSTRUCTION ON EMPHATIC SPECTROMETER USING MACHINE LEARNING
No full textNeutrinos are the most abundant massive fundamental particle universe, but because they interact with other matter only through the weak nuclear force, we know very little about them. The weak interaction decay is very well understood, however the process of creating some of the hadrons is only understood at the 10-40% level, resulting in an uncertainty in the neutrino flux at accelerators at the level of 10%. More measurements of the particle interactions (hadron interactions) that create neutrinos can help researchers reduce the uncertainty on the neutrino flux, and will enhance the capabilities of neutrino experiments like NOvA and DUNE in a variety of measurements such as neutrino cross-sections, sterile neutrino searches, and other BSM physics searches. The EMPHATIC collaboration\u27s goal is to measure these hadron production probabilities (cross sections) using a novel compact, table-top sized spectrometer. This talk describes the development of a machine learning algorithm to reconstruct particle tracks from the EMPHATIC spectrometer
ZENITH SKY BRIGHTNESS MEASUREMENTS DURING THE DAYTIME AND TWILIGHT
No full textThe writer carried out sky brightness measurements at zenith on clear days beginning in March 2023. A Sky Quality Meter manufactured by Unihedron was used for all measurements. In all cases, sky brightness values are in units of stellar magnitude/square arc-second. A Celestron neutral density filter with a transmission of 6.4 % was used for daytime measurements since the instrument cannot measure high levels of brightness. The goals of this study are to better understand the twilight arc of Venus and to collect brightness measurements of the daytime sky. These measurements can then be used as a baseline for measuring the sky brightness during solar eclipses. Some of the conclusions of this study are: The mean sky brightness for sunrise and sunset are 7.27 (0.099) and 7.45 (0.143) magnitudes/arc-second, respectively. The standard deviations are in parentheses. The mean sky brightness at the boundary of civil and nautical twilight before sunrise and after sunset are 13.68 (0.21) and 13.94 (0.20), respectively. In both cases, the difference between sunrise and sunset are statistically significant at the 95 % confidence level using the t-Test. It is also concluded that the summer haze brightens the sky by several tens of percent. The sky brightens in a nearly linear manner for solar zenith angles between 30° and 80°. This linear relationship breaks down for zenith angles higher than 80°. My summer measurements are consistent with a sky brightness of 1.9 (0.7) at a zenith angle of 0°. Finally, it is concluded that the time it takes for the sky to darken by a factor of 10 compared after sunset (or brighten by this same amount before sunrise) ranges from 16 minutes near summer solstice to 14 minutes at equinox. If Venus’ sky behaves in a similar manner then this would have to be taken into account when measuring its twilight arc