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Ecological and Educational Impacts of a Living Shoreline on St. Simons Island, Georgia, USA
Get PDFLiving shorelines encompass a range of nature-based alternatives to traditional coastal armoring structures. In addition to shoreline stabilization and protection, living shorelines are intended to meet conservation goals such as restoring habitat, delivering ecosystem services, and promoting ecological resilience to climate change. While early results have been promising, further monitoring is needed to better understand and evaluate the performance of living shorelines across a range of designs and environmental contexts, thereby informing coastal management. Nature-based shoreline protection is relatively new in Georgia, USA, where in 2015 the state’s fourth living shoreline was constructed of oyster shell and native plants on Lawrence Creek at Cannon’s Point Preserve, St. Simons Island. To assess ecological impacts of the living shoreline, undergraduate students conducted annual surveys of the oyster reef and marsh-edge plant community, spanning a seven-year period that included five years post-installation. Despite a series of tropical cyclones, the living shoreline successfully enhanced fringing salt marsh habitat occupied by the eastern oyster (Crassostrea virginica) and smooth cordgrass (Sporobolus alterniflorus), which increased in local density and spatial coverage. These foundation species are known to stabilize tidal creek banks, improve water quality, buffer uplands from storms, and provide nursery, refuge, and foraging sites for nekton. Moreover, the Lawrence Creek living shoreline has fostered experiential learning by students and served as a popular demonstration site for coastal managers, contractors, and property owners, thus raising public awareness and developing regional capacity to support broader utilization of living shorelines as a tool for coastal protection and conservation
Comparing a Georgia Reservoir With Solar-Powered Mixers to Another Without Mixers: Assessing Thermal and Oxygen Saturation and Nutrient Dispersion
Get PDFHarmful algal blooms (HABs) have been increasing over the last 50 years due to anthropogenic nutrient enrichment and increasing temperatures. One HAB control method is the use of solar-powered mixers. In this study we investigated the timing of thermal stratification, depth of the thermocline and oxycline, and dispersion of nutrients within the water column by comparing two reservoirs in Georgia, U.S.A. over a three-year period – Lake Varner (LV), which utilizes mixers, and Hard Labor Creek Reservoir (HLCR), which does not. Our data show that the onset of thermal stratification is within ± 2 days and appears at the same depth within both reservoirs. The timing of fall turnover consistently occurred one month earlier in LV than in HLCR. Both reservoirs had similar oxygen profiles during stratification, but in LV, dissolved oxygen levels increased more quickly in autumn compared to HLCR in all years. Both reservoirs had similar nutrient concentrations throughout the years and water column. These findings suggest the thermal, oxygen, and nutrient dynamics in the reservoirs are similar, despite LV having solar-powered mixers. Any differences can be attributed to LV being a slightly smaller and shallower reservoir
Perovskite CsPbBr3 Solar Cells With Novel Hole-Transporting Layer of Metal Complexes
Get PDFFor the first time, the novel application of Schiff-base copper complexes in all-inorganic perovskite CsBrBr3 solar cells has been explored and turns out they could be utilized as effective hole-transporting materials. Schiff-base copper complexes with halogen ligands (R=Cl and Br) are synthesized with an ease approach at a low cost, both of which exhibit decent power conversion efficiency of 4.55% and 5.71%, respectively, when being constructed into solar devices as hole transport layers. Thanks to high thermal/chemical stability of those Schiff-base metal complexes, the strengthened stability was achieved which is comparable to that of carbon-based CsBrBr3 solar cells. Although the power conversion efficiency is not as competitive as expected, the great potential exists for further optimizing the functionality of perovskite solar devices by finely tuning the photovoltaic properties of those Schiff-base metal complexes through coordinating ligands or replacing with other transition metals
THE EFFECT OF SALINITY AND PH ON A SPECIES OF SEA URCHIN LARVAE**
No full textClimate change is altering oceans in many ways such as modifications in salinity, temperature and pH. However, rarely are these factors experienced in isolation by organisms, rather they may be impacted by changes in all of them concurrently. This is especially challenging for marine larvae with calcium carbonate structures because survivorship and growth are susceptible to damage by changes in salinity and pH. We are specifically studying the Gulf and Caribbean sea urchin species Lytechinus variegatus; their aquatic habitat averages 27 ppt salinity and pH of 8.4. We predict that when they encounter salinities and pHs outside their normal range, there will be a decrease in survivorship and increase in skeletal abnormalities. To manipulate water conditions, we distributed larvae among 6 treatments with varying salinity and pH. Twenty - four hours after fertilization, larvae were placed in seawater of 25ppt, 27ppt or 32ppt in combination with pH of 7.6 or 8.4 for 6 possible treatments. Over the next 10 - 14 days, larval survivorship and skeletal abnormalities were measured. Results of this experiment show that survivorship was lower in treatments with a pH of 7.6 than pH of 8.4 regardless of salinity (p\u3c0.001) and skeletal abnormalities increased. However, salinity also impacted larvae because deviations from a salinity of 27ppt resulted in decreased survivorship (p\u3c0.001) and increased skeletal abnormalities. These results are consistent with our hypothesis and previous work, but replication is needed for statistical analysis of skeletal abnormalities. Lastly, there is a significant interaction between the effects of salinity and pH on mortality (p\u3c0.001) that may also be present in skeletal abnormalities, suggesting that the combinatorial effects of these factors should be studied. We can use these data to understand how the complexity of climate change is impacting our oceans
AN INTEGRATED APPROACH TO THE BIODIVERSITY AND CONSERVATION OF ODONTOTAENIUS DISJUNCTUS AND O. FLORIDANUS
No full textAccurate species delimitation and descriptions are a fundamental prerequisite for biological research. We are currently in the midst of the 6th mass extinction, with background extinction rates measuring 1000 times faster than Holocene background extinctions rates. Conservation biology often aims to assess and protect existing biological diversity and is also concerned with the sustainable use of natural resources over the long term. The assessment of biodiversity is the first step to the successful design of any conservation strategy. Identification of the organisms and the extent of morphological and genetic variability between them are the essential components of any biodiversity assessment. Amongst these, the identification of individual organisms via taxonomical and/or molecular means is the first step and vital for designing any conservation strategy. The bess beetles, Odontotaenius disjunctus and O. floridanus, are saproxylic beetles with distributions extending across the eastern United States and restricted to the highlands of central Florida, respectively. Recent studies inferred four well supported lineages that diverged during the Pleistocene and replace each other geographically across the eastern United States. However it has been shown that reliance on a single gene may be misleading because of asymmetrical gene flow, introgression, and other stochastic processes that affect mtDNA disproportionately. In this study, we use multilocus coalescent-based species delimitation methods and multivariate analyses of morphological data to examine whether the phylogroups merit taxonomic recognition as species in light of multiple lines of evidence under the general lineage concept
THE FEMALE MICROBIOME: PROBIOTICS, LACTOBACILLUS INCIDENCE AND ANTIBIOTIC RESISTANCE
No full textThe female urogenital tract has a unique microbiome specific to the body it inhabits. Maintenance of this microbiome’s health is vital to protect the reproductive and urinary systems from harmful pathogens, act as a barrier to foreign bacteria, and aid in overall functioning of the urogenital tract. This study explored flora native to the female urogenital microbiome (FUM) by rehydrating a culture of a Lactobacillus Beijerinck 1901 species by performing streak plate isolations, incubating in anaerobic and aerobic environments, and observing what each colony morphology looks like, as well as testing the bacteria’s susceptibility to specific antibiotics. Results showed that the macrolide erythromycin was most effective in inhibiting the growth of L. acidophilus. The zones of inhibition measured from erythromycin varied between 34 and 36 mm in diameter which makes L. acidophilus susceptible to it. The other antibiotics ciprofloxacin (quinolone) and sulfamethoxazole with trimethoprim (sulfonamide), were ineffective in inhibiting the growth of L. acidophilus. Three name brand probiotic yogurts were selected and studied to determine which promoted the growth of L. acidophilus best. Results indicated that Yoplait® showed to be the most successful. Finally, an experiment was conducted on 10 female participants ages 19-34 that are students, faculty, or staff at Brewton-Parker College in Mt. Vernon, Georgia. Urine samples were collected, plated, incubated at 37°C for 48 hours, and analyzed to ascertain the microbiome composition of the individuals. The experimental group of participants ingested a probiotic yogurt daily for 14 days, while the control group were given no changes in their diet. At the end of the 14 days, the results were examined for potential changes in the makeup of each participant\u27s FUM. The results showed that all of the participants in the control group except for one, had a decrease in Lactobacillus colonies, and all of the participants given the probiotic yogurt except for one, had an increase in Lactobacillus colonies
THE RELATIONSHIP BETWEEN SHOULDER INTERNAL AND EXTERNAL RANGE OF MOTION AND ISOMETRIC GRIP STRENGTH OF COLLEGIATE BASEBALL AND SOFTBALL ATHLETES
No full textIn order to achieve high velocity and accuracy, baseball and softball players place large amounts of stress on their arms during pitching. Baseball pitchers use the overhead throwing motion at a higher frequency and force than other positions and injuries can cause athletes to miss games or decrease their performance output. This study investigated the relationship between shoulder internal and external range of motion (IROM and EROM), and isometric grip strength of Brewton-Parker College baseball and softball players. Athletes were surveyed to collect demographic information and injury history. Participants laid on a physical therapy table in the supine position with their arms abducted 900 away from their body for shoulder IROM and EROM measurements using a goniometer. The 19 baseball (9 injured) and 14 softball (5 injured) participants were also tested for isometric grip strength in their throwing arms with a hand dynamometer. Results for baseball: average shoulder EROM of non-injured: 105.9° ± 8.0, injured: 98.56° ± 6.04. Average shoulder IROM non-injured: 61.0° ± 8.74, injured: 57.67° ± 7.83. Average isolated grip strength non-injured: 49.0 ± 11.10 kg, injured: 50.14 ± 4.75 kg. Results for softball: average shoulder EROM of non-injured: 90.56° ± 12.41, injured: 63.60° ± 20.71. Average shoulder IROM non-injured: 72.89° ± 18.03, injured: 63.0° ± 22.77. Average isometric grip strength non-injured: 28.11kg ± 5.54, injured: 25.38kg ± 5.15. A student t-test was conducted to compare injured and uninjured conditions. There was a significant difference between injured and uninjured baseball players (t=0.046), p=0.05 as well as between injured and uninjured softball players (t=0.015) for shoulder EROM but not for IROM or grip strength. When comparing uninjured baseball players to uninjured softball players: for EROM (t=0.010) and grip strength (t=0.0002) there was a significant difference and lastly when comparing injured baseball and softball players: only EROM (t=0.0263) showed significant difference. Grip strength increased with body mass index (BMI, and are therefore positively correlated
SYNTHESIS, GELATION, AND STEADY-STATE FLUORESCENCE PROPERTIES OF N-(HYDROXYPHENYL)ALKANAMIDE DERIVATIVES**
No full textTo understand the relationship between molecular structure and the gelation properties, N-(hydroxyphenyl)alkanamides having OH group on the ortho, meta, positions of phenyl rings as well as varying alkyl chain length (n = 12, 14, and 18) have been synthesized. Synthesized compounds were characterized using spectroscopic and thermal methods. Gelation studies of the 5 wt % of prepared gelators were investigated in various polarity liquids and were characterized based on their physical appearance, and gel melting temperature. Absorption and steady-state fluorescence and thermal properties of the, N-(hydroxyphenyl)alkanamides will be presented
MOON PACKING AROUND AN EARTH-MASS PLANET
No full textThe giant planets of the Solar System host systems of multiple moons, where the Earth has only one large natural satellite, Luna. There are many man-made satellites in residence around the Earth and a handful of small asteroids that can persist as temporary natural satellites. With this observation, one can wonder how many large natural satellites (i.e., moons) could orbit the Earth over long timescales. We perform a series of N-body simulations that consider three different satellite masses (Ceres-, Pluto, and Luna-like), where each mass type is nested around an Earth-mass planet orbiting a Sun-like star. The innermost moon begins orbiting near the host planet’s Roche radius, while additional moons are added using the mutual Hill radius between adjacent satellites. Our simulations reveal, as an upper limit, that an Earth-mass planet could host up to 7 Ceres-mass, 4 Pluto-mass, or 3 Luna-mass moons with an uncertainty of 1 moon respectively. However, the true limitation for moons is likely to be fewer than these upper limits as gravitational interactions with other planets can periodically alter the extent of the host planet’s Hill radius or outward tidal migration (due to interactions with the host planet itself) can force collisions or scattering events
COMPARISON OF STRESS-INDUCED AGGRESOMES IN ADENOVIRUS E4 11K INFECTIONS AND CDCL2 TREATMENT**
No full textDuring an adenovirus infection, the viral protein E4 11k is responsible for relocalizing specific host cell proteins in order to disrupt normal cellular function to support viral replication. E4 11k has been shown to relocalize processing body (p body) proteins to cytoplasmic aggresomes. These aggresomes are regions of misfolded protein storage that are induced when there is cellular stress. The p body protein Ddx6 has been found in E4 11k-induced aggresomes, but it remained in p bodies in cells treated with the chemical stressor cadmium chloride (CdCl2). Ddx6 was also found to bind directly to E4 11k, which suggests that E4 11k may possess a mechanism to relocate Ddx6 during an infection. Ddx6, along with Pat1b and Edc3, are scaffolding proteins involved in p body formation. As scaffolding proteins are involved in many protein-protein interactions, it is likely the mechanism E4 11k uses to relocate other p body proteins is through interaction with one of these proteins. HeLa cells will be treated with CdCl2 to induce aggresome formation and several p body proteins will be stained, along with gamma tubulin, to indicate which p body proteins are relocalized to aggresomes. We expect at least one p body scaffolding protein to move to aggresomes during this cellular stress