Regulatory Mechanisms in Biosystems (E-Journal - Dnipro National University)
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Topic 9: Graphical user interfaces
No full textObjectives of this topic:
Understand the concept of a graphical user interface,
Build graphical user interfaces and handle various events,
Recognize different components such as buttons, text fields, frame
Variable post-release mortality in common shark species captured in Texas shore-based recreational fisheries
No full textThe practice of catch and release fishing is common among anglers but has been shown to cause unintended mortalities in some species. Current post-release mortality estimates used in coastal shark stock assessments are typically derived from boat-based shark fisheries, which differ from shore-based operations that expose sharks to potentially more stressful environmental and handling conditions. Recreational post-release mortality rates in shore-based fisheries must be quantified to improve stock assessment models and to create guidelines that protect species from overexploitation. Here, we partnered with experienced anglers acting as citizen scientists to deploy pop-up satellite archival transmitting tags (PSAT, n = 22) and acceleration data loggers (ADLs, n = 22). on four commonly caught sharks including the blacktip shark (Carcharhinus limbatus, n = 11), bull shark (Carcharhinus leucas, n = 14), tiger shark (Galeocerdo cuvier, n = 6), and great hammerheads (Sphyrna mokarran, n = 2). Mortality occurred within minutes to hours post-release. If evidence of mortality occurred after normal diving behavior had been re-established for 10 days, then the mortality was considered natural and not related to the catch-and-release process. Post-release mortality estimates ranged from 0% for bull and tiger sharks to 45.5% for blacktip sharks. Of the two great hammerheads, one died within 30 minutes post-release while the other exhibited mortality characteristics 14 days after release. Moribund blacktip sharks experienced on average 3.4–4.9°C warmer water compared with survivors. Recovery periods were estimated for survivors of each species and were highly variable, differing based on duration of tag deployment. High variability in responses to capture and release between species demonstrates the need for species-specific assessments of post-release mortality in shore-based recreational fisheries
Analysis of Seasonal Changes in Community Composition of Seagrass Epiphytes in Aransas Pass, Texas
No full textCollege of Science, Biology, Organismal Science (Plant); Faculty Mentor: Dr. Kirk CammarataGenerally, the type, and number of epiphytes found on seagrasses varies based on the time of year and the nutrient load of water, including man-made nutrient sources such as wastewater effluent. This study will examine the changes in community composition of epiphytes found on T. testudinum as a function of porewater nutrients and other environmental factors. Epiphytes will be removed from seagrasses collected seasonally from the ICW RV Park in Aransas Pass, Texas. Sites within the study area were chosen based on their proximity to the release point of wastewater effluent from the Aransas Pass Wastewater Treatment Plant. Comparative analysis of fluorescence was done using four wavelengths: 415nm and 680nm were used to determine the amount of green pigments in the sample associated with green algae and 530nm and 576nm were used to determine the amount of red pigments in the sample associated with red algae. These measurements were then compared to determine the ratio of red to green pigments within the samples. Samples will also be run through a full pigment analysis. This will be done using acetone to extract the color from the samples and then analyzing the solution produced in a spectrophotometer. Preliminary results show that both summer and winter samples had higher levels of red algae than green algae when comparing fluorescence analysis. However, individual sites differ, with some showing decreases in red pigment domination and others showing increases from summer to winter. However, further analysis and sampling needs to be done before any final patterns can be suggested. This project will allow for a better picture of the seasonal changes in epiphyte composition on T. testudinum and provide some comparisons between sites with differing nutrient inputs, especially those influenced by wastewater effluent
Freeze-Disturbance effects on biomass allocation in expansion of Black Mangrove (Avicennia Germinans) along a latitudinal gradient in Texas
No full textIn response to warming minimum temperatures, Avicennia germinans is encroaching poleward on the Texas Gulf Coast (TGC) into saline marshes dominated by Spartina alterniflora and Batis maritima. Increased Avicennia cover provides greater protection from soil subsidence and shoreline retreat. However, intense freeze disturbances cause widespread mangrove mortality reversing succession, and increasing the risk of soil subsidence and shoreline retreat due to the loss of below-ground biomass. We conducted a “natural experiment of opportunity” to measure below- and above-ground biomass allocation in Avicennia recovering from catastrophic disturbance caused by the 2021 Winter Storm Uri at sites along a freeze-disturbance gradient across the South and Central TGC. Port O’Connor (28.46°N) was the most severely affected site, Cohn Preserve on Mustang Island (27.71°N) was moderately affected, and Laguna Atascosa National Wildlife Refuge (26.35°N) was minimally affected (min. temp. °C ~ -9.0, ~ -7.4, ~ -5.5 respectively). A second freeze event occurred in December 2022 that severely affected Port O’Connor and moderately affected Cohn Preserve (min. temp. °C ~ -6.6, ~ -5.8 respectively). In an additional methods experiment, we quantified differences in root productivity in in-growth cores containing either peat moss or local substrate at each site. Multiple root ingrowth cores were inserted near the canopy edge of isolated Avicennia shrubs (n=6; 5 at Port O’Connor) at the three sites and collected at 4-month intervals (total cores = 102). Root productivity (g * (m-2 day1)) assessed in a one-way ANOVA and Tukey multiple comparisons, increased with increasing freeze-disturbance effects (F2,28 = 6.386, p<0.01, Port O’Connor: mean = 0.192, sd = 0.188, Cohn Preserve: mean = 0.065, sd = 0.081, Laguna Atascosa: mean = 0.047, sd = 0.089). Using the below-and above-ground relative growth rates to assess the root:shoot biomass allocation ratio, we found an increasing ratio (greater roots to shoots) with increased freeze disturbance (one-way ANOVA and Tukey HSD tests, F2,12 = 6.049, p<0.05, Port O’Connor: mean = 0.191, sd = 0.118, Cohn Preserve: mean = 0.061, sd = 0.066, Laguna Atascosa: mean = 0.015, sd = 0.01). Further, we found no clear trend in quantity or variability in root productivity between native and peat moss substrate types in root ingrowth cores for root biomass at any site (F2, 53 = 0.021, p=0.8). However, peat moss ingrowth cores did consistently have less root necromass after the Dec. 2022 freeze suggesting better survival or lower turnover. Peat moss ingrowth cores contained lower quantities of live root biomass indicating higher rates of root mortality or a stunting effect on root productivity post-second freeze. This finding suggests that cumulative impacts of two freezes occurring less than two years apart are greater than the effects of individual freezes. Increasing root productivity with greater freeze disturbance suggests that recovering standing root biomass may be important for the recovery of above-ground biomass in freeze affected Avicennia. Rapid recovery of below-ground biomass will also contribute to ameliorating rates of soil subsidence and shoreline retreat. Lastly, we found that peat moss is a viable substrate type for future root ingrowth studies if the focus of the study is on total root biomass. However, if a second freeze event occurs during the root ingrowth study, there may be unequal effects between peat moss and local substrate.Life SciencesCollege of Scienc
Insights into glacial processes from micromorphology of silt-sized sediment
No full textMeltwater plume deposits (MPDs) from marine sediment cores have elucidated clearly connected, yet difficult to constrain, relationships between ice-marginal landform construction, grounding-zone retreat patterns, and subglacial hydrology for several glacial systems in both hemispheres. Few attempts have been made, however, to infer coveted details of subglacial hydrology, such as flow regime, drainage style, and mode(s) of sediment transport through time from grain-scale characteristics of MPDs. Using MPD, till, and ice-proximal diamicton samples collected offshore of six modern and relict glacial systems in both hemispheres, we examine whether grain-shape distributions and microtexture assemblages (collectively, grain micromorphology) of the silt fraction are the result of subglacial meltwater action, or are indistinguishable from glacial proximal and subglacial sediments from the same region. We find that of all grains imaged (n=9,400), three-quarters can be described by one-quarter of the full range of measured shape morphometrics, indicating widespread and efficient abrasive processes in subglacial environments. Microtexture analysis reveals that while grains comprising MPDs show evidence of edge rounding more often than tills, fluvial microtextures occur in modest amounts on grain surfaces. Furthermore, MPDs retain many mechanical (i.e., glacial) textures in comparable abundances to tills. Significant alteration of MPDs from till sources is observed for systems (1) for which intensive, potentially catastrophic, meltwater drainage events in the Holocene are inferred from marine geologic records, and (2) with comparatively less mature till grains and a contribution of supraglacial melt to the bed, indicating that quantifiable grain-shape alteration of MPDs may reflect a combination of young till, high-energy flow of subglacial meltwater, persistent sediment entrainment, and/or long sediment transport distances. We encourage future works to integrate grain micromorphology into site-specific marine sediment analyses, which may distinguish periods of persistent, well-connected subglacial discharge from periods of sporadic or disorganized drainage and provide context needed to estimate sediment fluxes and characterize ice response to subglacial meltwater transmission. In addition, this work demonstrates that glacial and fluvial surface textures are retained on silts in adequate abundance for microtexture analysis.The authors acknowledge the captains, crews, and science parties who over the decades collected the dozens of cores sampled for this research. Funding for this research comes from a subcontract to the University of Virginia to LEM as part of the larger collaborative Thwaites Offshore Research grant (NSF OPP Grant 1738942 and Natural Environment Research Council grant nos. NE/S006664/1 and NE/S006672/1). We thank M. Esteves, V. Stanley, and the curatorial staff at the Oregon State University Marine and Geology Repository for their assistance with sample requests. D. Buskard and M. Prakash were instrumental in developing the MATLAB script. The Quanta 650 SEM is housed in the Nanoscale Materials Characterization Facility, and we thank the staff for providing the first author instrument training. Figures use the colorblind-friendly palette “Java” from the MetBrewer color package developed by B. R. Mills (https://github.com/BlakeRMills/MetBrewer). Data analysis and interpretation presented in this study was conducted at the University of Virginia in Charlottesville, Virginia. The University of Virginia was built by enslaved laborers on the unceded lands of the Monacan Nation, who have protected and 545 cultivated these lands for thousands of years. The authors acknowledge and respect their stewardship of the land, past, present, and future
Linking shape to substance: Exploring morphometrics and geochemical records in eastern oyster shells from subtropical estuarine systems
No full textA thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Fisheries and MaricultureThis study aimed to investigate the resilience of eastern oysters (Crassostrea virginica) exposed to environmental stressors such as droughts and floods. The primary objectives were to assess the potential of geochemical records within oyster shells to discern past environmental variability and to evaluate the growth performance of these oysters in dynamic, subtropical estuarine systems subject to these major climactic events. Eastern oysters have been established as reliable bioindicators of water quality and records of their native habitats. Previous studies utilizing stable isotopes (?13C and ?18O) to track freshwater inflow patterns faced challenges due to multiple covarying factors. This study employed Ba/Ca ratios as an alternative proxy and examined their relationship with salinity. Notably, shell ?13C values demonstrated a remarkable match with estimated salinity values, highlighting the usefulness of this chemical proxy alone or in combination with ?18O for similar investigations. Despite their resilience, oyster growth performance can be adversely affected by environmental disturbances. Oysters from low, fluctuating salinity environments exhibited the greatest shell growth, followed by those inhabiting intermediate, then high, stable salinity environments. Which suggests that freshwater inflows following flood events positively influence estuarine functioning and oyster health, likely due to increased water turbidity, food availability, and reduced susceptibility to predation and disease. With projections of drier climates and variable precipitation patterns leading to more extreme temperature and salinity levels, eastern oysters may face greater growth limitations in the future. Therefore, understanding how environmental disturbances, including freshwater inflow dynamics, differentially impact oyster growth is crucial for the management and protection of this increasingly vulnerable keystone species.Fisheries and MaricultureCollege of Scienc
Rafael and Virginia Galvan at a fireplace
No full textRafael and virginia Galvan standing togeather by the fireplac
Improving the voltage and lifetime in aqueous redox flow batteries utilizing the organometallic [Fe(bpy)3]2+/3+
No full textDepartment of Physical and Environmental Sciences, College of ScienceLong term battery storage is needed for renewable energy sources to buffer their variable output. Redox flow batteries (RFBs) have the potential to store large amounts of energy for on-demand power generation. Current issue: low energy density due to poor solubility of the active species and low voltage outputs. Robust, high voltage catholytes are needed. Iron (II/III) tris-2,2’-bipyridine ([Fe(bpy)3]2+/3+) is a suitable catholyte. This work introduces a new way to synthesize [Fe(bpy)3]2+ and methods to improve performance.This research was supported by funding from The Welch Foundation. Dr. Mark Olson – Chemistry Program Coordinato
A Lady and her Dogs
No full textA Lady stands besides a car with her Dogs sitting inside of it with debris in and around the ca
I can't see you; can you hear me? Gender norms and context during in-person and teleconference U.S. Supreme Court oral arguments
No full textFemale attorneys at the U.S. Supreme Court are less successful than male attorneys under some conditions because of gender norms, implicit expectations about how men and women should act. While previous work has found that women are more successful when they use more emotional language at oral arguments, gender norms are context sensitive. The COVID-19 pandemic prompted perhaps the most radical contextual shift in Supreme Court history: freewheeling in-person arguments were replaced with turn-based teleconference arguments. This change altered judicial decision-making and, I argue, justices’ assessments of attorneys’ gender performance. Using quantitative textual analysis of oral arguments, I demonstrate that justices implicitly evaluate gender performance with different metrics in each modality. Gender-normative levels of emotional language predict success in both formats. Function words, however, only predict success in teleconference arguments. Given gender’s salience at the Supreme Court and in broader society, my findings prompt questions about the extent to which women can substantively impact case law