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RELATIONSHIP OF CHAIN-FORMING ARAPHID DIATOM COMMUNITIES FOUND IN HYDROLOGICALLY VARIABLE WETLANDS
No full textDiatoms, a common group of algae made of silica, are found to be high quality bioindicators. The former Bo Ginn National Fish Hatchery in Millen, Georgia, United States was used to study the modifications done on spring-fed wetlands. Ponds were modified based on inundation period and featured eight total wetlands, five were temporarily inundated and three were permanently inundated. All samples were collected using a benthic core sampler. The goals of this research were to (1) identify diatoms to the lowest taxonomic level, (2) compare algal metrics between the varying inundations and the top versus bottom of the sediment cores and (3) observe and analyze chain formation of Staurosira construens Ehrenberg. Previous research on this project found that S. construens dominated all samples with over 50% relative abundance. It is a chain-forming diatom and there is importance in observing these chains in order to document reproductive and diminution series traits that might be observable within samples. Current data shows high abundance of chains and the average number of frustules within a chain being four frustules. Chain showed diatom’s ability to survive and reproduce, leading to increased number of chains. There was a higher prevalence of chains within the temporary wetlands; however, there were more total temporary ponds overall. These digested samples were compared to live samples collected from the spring, the wetlands’ water source, and there were higher length of chains. There is theory that length of chain varied on both the practice of digestion and mounting of slides or the live collection of samples from the spring. This research contributes to the understanding of the effects of anthropogenic use on the ecosystem even years after the hatchery closed along with the relationship between chain length and size within sediment cores of top and bottom as well as inundation
DETERMINING THE UPPER THERMAL LIMITS OF THE WHITE TUBERCLED CRAYFISH (PROCAMBARUS SPICULIFER, LECONTE 1856)**
No full textThe southeastern United States is a biodiversity hotspot, yet many of its freshwater species, including crayfish, face threats from habitat changes and increasing temperature. Despite the ecological importance of crayfish, physiological data critical for predicting species\u27 responses to environmental changes, such as thermal tolerance, are limited. This study aims to investigate the upper thermal limit (UTL)—the temperature at which physiological function breaks down due to thermal stress—of Procambarus spiculifer (the White Tubercled Crayfish), a common stream-dwelling species in cool-water habitats across the southeastern United States. The UTL of P. spiculifer will be determined in a controlled experiment by steadily increasing water temperature until the breakdown of physiological function is indicated by a lack of righting response. Understanding the thermal tolerance of P. spiculifer has the potential to provide crucial data for conservation efforts, offering insight into the species’ potential responses to rising temperatures and habitat changes. These findings will contribute to broader ecological predictions and management strategies aimed at preserving crayfish biodiversity in the face of climate change
EXTRACTION OF PER- AND POLYFLUOROALKYL SUBSTANCES FROM MUSCLE TISSUE SAMPLES OF FISH IN THE CHATTAHOOCHEE RIVER AND ITS TRIBUTARIES**
No full textPer- and polyfluoroalkyl substances (PFAS) are man-made \u27forever chemicals,\u27 meaning they do not naturally break down once they enter the environment. They often enter a water supply through improper waste disposal or human activity, where they may accumulate within the bodies of aquatic life. This research aims to analyze fish flesh samples from the Chattahoochee River via gas chromatography-mass spectrometry (GC-MS) for the presence of PFAS. Currently, the goal of this project is to develop a method of preparing the flesh samples for analysis. To do this, non-Chattahoochee test samples will be deliberately injected with a known mixture of PFAS. Organic solvents will be used to extract the PFAS from the fish, which will then be derivatized for detection via GC-MS. This analysis, when compared to the original mixture of PFAS injected into the sample, will show the reliability of the method. It will also be used to determine the loss of PFAS during the preparation, derivatization, and analysis process. This development will ultimately yield a reliable method for flesh sample analysis and allow the true PFAS content to be extrapolated from the Chattahoochee flesh sample data. Once the method is refined, the samples from Chattahoochee River fish can be analyzed to determine the presence, identity, and amount of PFAS in the flesh. Since fish of varying species and catch locations will be tested, this data will not only illustrate the overall severity of PFAS pollution in the Chattahoochee River, but also help determine which species and parts of the river have been impacted the most
BRIGHTNESS CHANGES IN THE SEMI-REGULAR VARIABLE STAR RZ-ARIETIS
No full textWe have measured the V-filter brightness of the semi-regular variable star RZ-Arietis 69 times since November 8, 2023. Our measurements were made with a filter closely matching the Johnson V-band. We measured four periods rainging from 38 to 60 days. (The period is the length of of time for the star to go from brightness maxima to the next brightness maxima.) Our results are consistent with two different primary periods for this star (~38 and ~58 days). This is consistent with previous studies. Our results were compared to previously reported brightness measurements in the American Association of Variabile Star Observers (AAVSO) database. As of early 2024, the AAVSO database had 909 V-filter brightness values. Schmude measured 19 periods from this database. Therefore, we have 23 total periods. The mean period length is 51 days with a standard deviation of 12 days. We also conclude that the primary period can change by over 35 % in two months. The mean brightness, covering all stages in the bightness cycle for different apparitions was also measured. We conclude that the mean brightness remained near magnitude 5.75 for most of the time between 1983 and early 2021, but dropped suddenly to 5.95 in late 2021. An apparition is the period between July and the following March when RZ-Aries is far enough from the Sun to be studied
PROJECT D.O.R.A.: EXPLORATION ROVERS USING ROS2 AND SLAM**
No full textResearch in Simultaneous Localization and Mapping (SLAM) is advancing rapidly, driven by both commercial and scientific goals, including terrain mapping with stationary devices and mobile vehicles. Project DORA, a project under the NASA MINDS initiative, seeks to prototype a fleet of autonomous rovers for surveying and data collection on lunar surfaces, aligning with NASA’s plans to deploy autonomous rovers for lunar exploration within the next three years. The fleet consists of one Youth-ATV and two smaller swarm rovers equipped with advanced sensors like LiDAR and RGB-D cameras to collect detailed color and surface data. Leveraging the ROS2 framework, 3D printing, and electrical engineering, the rovers navigate obstacles, communicate with each other and a base station, and achieve preset goals efficiently. The project integrates innovative solutions in terrain mapping, path-planning algorithms, wireless communication, and energy management to enhance data accuracy and exploration efficiency. By addressing key technological challenges, Project DORA hopes to contribute to the success of NASA\u27s Artemis missions, supporting sustainable exploration of extraterrestrial environments
HIP MOBILITY EFFECTS ON BAT SPEED IN COLLEGIATE BASEBALL AND SOFTBALL
No full textSwing sports athletes must be capable of carrying out the motions required to hit a ball great distances. An athlete’s range of motion (ROM) in the hips is, therefore, essential for having a successful athletic career. In swing sports like baseball and softball, athletes rotate around the body’s center; thus, the hips must have an optimal ROM for force generation. The purpose of this experiment was to identify if hip mobility has an effect on bat speed in swing sports. Twenty-five swing sport athletes (20 male and 5 female) were sampled in this study. A goniometer measured the athlete\u27s internal and external hip ROM in both the lead and launch hips. The participants took five swings from a tee with a sensor attached to the knob of the bat so that an average bat speed could be calculated. Pearson correlation tests showed no significant associations between lead hip internal (p = .88, r = .03), lead hip external (p = .15, r = .3), or launch hip external ROM (p = .44, r = .16) and average bat speed. However, a significant positive relationship was found between launch hip internal ROM and average bat speed (p=.01, r = .5). Therefore, the hip\u27s range of motion has been shown to have moderate to no effect on the swing speed of baseball and softball players. However, as internal hip rotation ROM in the launch leg increases, bat speed increases. This research can be used in swing sport training to further develop athletes and allow them to make minute adjustments to be able to perform at the highest of their anatomical abilities
Breaking Barriers: Investigating Gender Dynamics in Introductory Physics Lab Classes
Get PDFThe persistent underrepresentation of women and other gender minorities in physical science fields has been an ongoing concern. This study investigates gender dynamics in introductory physics laboratory courses, focusing on whether students of different gender identities exhibit equal inclination and confidence in conducting lab experiments, and whether they face barriers that impact their participation. Conducted across three institutions and involving non-physics STEM students enrolled in algebra-based and calculus-based physics courses, the study found mixed results, with two institutions showing no significant gender-based differences in participation levels during lab activities, while one institution demonstrated significant differences. Chi-square tests revealed no significant association between gender and task preference or comfortability, though the small dataset suggests the need for further investigation. While quantitative analysis provided limited evidence of systematic barriers, qualitative feedback revealed that some female students experienced challenges related to gender dynamics, such as perceived assumptions about competence, being overlooked during discussions, and hesitation to voice opinions in male-dominated groups. These findings highlight the complex influence of gender and institutional factors on laboratory experiences and underscore the need for creating inclusive environments that promote equitable engagement and participation for all gender identities in STEM education
HUMAN ACTIVITY LEVELS NEAR MONITORED SECONDARY CAVITY NESTING FOREST BIRD BOXES BEFORE AND AFTER CONSTRUCTION OF A HOUSING COMPLEX**
No full textWithin the past 50 years, avian populations have become alarmingly reduced throughout North America. Most of this loss is due to habitat changes associated with increased human urbanization. Urbanization results in direct avian mortality by collisions with human infrastructure such as building windows, cars, cell phone towers, wind turbines, and electric wires. Urbanization also has indirect impacts on bird population size through reduced air and water quality, noise pollution, increased human presence in remote areas, and the presence of human pets. We have the opportunity to examine changes in the presence of humans in a 77-acre forest patch adjacent to the University of North Georgia, Gainesville campus. Five acres of this forest was removed for the construction of a housing complex in 2022. We have been monitoring secondary cavity nesting birds in this forest since 2016, through incidental observations (2016-2020) and wildlife cameras (2021-2024). For the research we are presenting here, we hypothesize that we will find an increased presence of humans in the entirety of our forest patch following the construction of this housing
ENVIRONMENTAL JUSTICE AND PFAS CONTAMINATION IN GEORGIA: SOCIOECONOMIC DISPARITIES AND DRINKING WATER QUALITY ANALYSIS
No full textEnvironmental justice (EJ) research has highlighted the disproportionate exposure of low-income communities and communities of color to environmental hazards, including poor drinking water quality. Per- and polyfluoroalkyl substances (PFAS), synthetic chemicals known for their persistence and adverse health impacts, represent a growing concern in the context of EJ. Exposure to PFAS through drinking water has raised alarms about inequities, as contamination sources often align with socioeconomic and racial disparities. To address PFAS health risks, the U.S. EPA implemented new regulations in 2024, establishing Maximum Contaminant Levels (MCLs) for six PFAS and a Hazard Index for mixtures, aiming to protect vulnerable populations. In Georgia, PFAS contamination is linked to industrial, military, and transportation activities, with significant contributors such as the carpet industry in Dalton, airports, military installations, and landfills. These sources have led to contamination in drinking water systems, legal disputes, and increased water treatment costs, further burdening communities already facing socioeconomic challenges. However, most prior EJ studies regarding PFAS have focused on national trends or county-level data, leaving a knowledge gap regarding local correlations between PFAS contamination, socioeconomic factors, and community demographics. This study addresses that gap by analyzing city-level PFAS data (UCMR5), socioeconomic indicators, and contamination sources across Georgia. Our findings reveal that cities with detectable PFAS contamination in drinking water have lower median household incomes and a higher proportion of residents from communities of color compared to statewide averages. These results suggest systemic disparities in the siting of PFAS sources and drinking water exposures, underscoring the urgent need for equitable environmental policies. By integrating EJ frameworks with PFAS contamination analysis, this study provides actionable insights for state and local governments to prioritize mitigation strategies that address the disproportionate impacts on vulnerable populations, thereby advancing environmental equity in Georgia
MICROSTRIP BASED MICROWAVE BIOSENSORS WITH POLYMER RESIN STRUCTURE
No full textHighly sensitivity and noninvasive biosensors has gained a lot of interest in industrial and medical technology. These noninvasive sensors operate based on the material\u27s response to the applied electromagnetic field. Microstrip line-based transmission lines can generate significantly strong electromagnetic field within a limited range. The proposed microstrip-based biosensors are capable of sensing concentration of glucose in fluid inside a polymer resin structure for a range of microwave frequencies