Texas A&M University – Corpus Christi
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In Situ and remote sensing of aerosol properties and their influences in tropical oceanic warm rain systems
Full text linkThis study includes two parts. First, in-situ aerosol particulates with size below 2.5 microns (PM25) observations are collected from the Nueces headwaters to the Texas coast, ending in Nueces Bay in April 2023. The potential links between parameters involved in the atmospheric and aerosol samples are examined. The second part focuses on examining the relationships between the properties of oceanic warm rain systems and aerosols by using remotely sensed observations. By utilizing the Navy Aerosol Analysis and Prediction System (NAAPS) AOD reanalysis product, collocated with Global Precipitation Measurement (GPM) data from 2014-2022, we examine the relationships between the aerosol types and concentrations and properties of warm rain systems over the Eastern Pacific and the Central Atlantic. The warm rain systems are selected by maximum echo top heights less than 5 km and size smaller than ~250 km2. Over the Central Atlantic, dust particles are the most abundant aerosol and peak in JJA with the emergence of the Saharan Air Layer. Over the Eastern Pacific, smoke and sulfate tend to be the most abundant particles with both peaking in MAM. We also examined the relationships between AOD and the properties of warm rain under different large-scale descent and near surface air temperature environments collocated from ERA5 reanalysis product. This study suggests the type of aerosol as well as large scale thermodynamic environmental parameters are important when understanding the relationship between aerosols and warm precipitation. However, the overall influence of aerosols in these systems does not seem to be significant based on the statistically analysis.Physical and Environmental SciencesCollege of Scienc
NOx source apportionment and oxidation in a coastal urban airshed using stable isotope techniques
Full text linkNOx (NO + NO2) emissions decrease urban air quality, and its subsequent deposition can be a significant source of excess nitrogen loading to coastal waters. Photochemical reactions between volatile organic compounds and NOx in the atmosphere create ozone (O3). Previous studies suggest coastal urban airsheds tend to have a NOx limited ozone regime, so an increase in NOx would lead to an increase in O3. The first step to NOx emission mitigation and thus ozone reductions in these regions is to quantify the contributions of NOx sources. These sources have unique nitrogen isotopic compositions (δ15N-NOx) or “source signatures”, which allow the use of isotope mixing models to aid in determining emission source contribution. The corresponding oxygen isotopic composition (δ18O-NO2) of NO2 can be used to estimate the NO oxidation chemistry after emission from the sources. To investigate NOx dynamics in a representative coastal urban air shed, NOx and NO2 were passively sampled at four NOx and ozone monitoring stations of the City of Corpus Christi, Texas each month for one year and the nitrogen and oxygen isotopic composition (δ15N, δ18O) of each sample was measured. The δ15N-NOx and δ18O-NO2 values were applied to a Bayesian type mixing model to determine the apportionment of point (natural gas combustion) and nonpoint (biogenic soils, vehicles, marine shipping, biomass burning, and lightning) NOx sources in the air shed and determine NO oxidation chemistry (i.e. peroxy radical vs ozone pathway). Often, studies using this Bayesian mixing model include biomass burning and lightning as sources however, these are not continuous sources, and biomass burning and lightning events do not always produce enough NOx to be considered significant. We present an alternative to this “blanket” source approach by coupling HYSPLIT airmass back trajectories with lightning and fire remote sensing products to determine the significance of intermittent sources before including in a mixing model. This study also uses a more detailed approach to estimating the source signature of vehicular and industrial emissions. The average source signature for the combined diesel and gasoline vehicle fleet emissions was weighted according to proportion of diesel and gasoline emissions reported for the study region, and the industrial emission signature was expanded to also include marine shipping NOx emissions (weighted according to ship-type). This study determined NOx emissions are dominated by biomass burning emissions (41%) followed by vehicular (34%), lightning (12%), industrial (7%), and biogenic (6%) emissions and time periods of significant NOx emissions from biomass burning coincide with the burning season in Mexico. Emission apportionment results are within agreement of previous studies, but it is important to note the overlap in source signatures incorporated into the Bayesian mixing model. The most common isotopic endmembers for vehicular, biomass burning, and lightning overlap, and therefore introduce increased error into apportionment models. This highlights the future importance of having isotopic source signatures that are representative of specific regions of study. It was determined that the peroxy radical pathway (65%) is the dominant pathway for NO oxidation, with an increase in oxidation via the ozone pathway correlating with ambient ozone concentration. This study provided a first attempt at calculating the kinetic isotope effect (KIE) and subsequent enrichment factor of the radical pathway, estimated to be approximately -15‰. Results provide a greater understanding of NOx and ozone dynamics in coastal urban airsheds and can directly aid in the modification of coastal communities’ ozone action plans. Results enhance the understanding of atmospheric oxidative chemistry, information that is vital to constrain chemical transport models. Accurate source apportionments will be extremely useful for creating air quality regulations and ozone mitigation.Physical and Environmental SciencesCollege of Scienc
Detection of astrophysical neutrinos at prospective locations of dark matter detectors
No full textWe study the prospects for detection of solar, atmospheric neutrino, and diffuse supernova neutrino background (DSNB) fluxes at future large-scale dark matter detectors through both electron and nuclear recoils. We specifically examine how the detection prospects change for several prospective detector locations [Sanford Underground Research Facility (SURF), SNOlab, Gran Sasso, China Jinping Underground Laboratory (CJPL), and Kamioka] and improve upon the statistical methodologies used in previous studies. Because of its ability to measure lower neutrino energies than other locations, we find that the best prospects for the atmospheric neutrino flux are at the SURF location, while the prospects are weakest at CJPL because it is restricted to higher neutrino energies. On the contrary, the prospects for the DSNB are best at CJPL, due largely to the reduced atmospheric neutrino background at this location. Including full detector resolution and efficiency models, the CNO component of the solar flux is detectable via the electron recoil channel with exposures of ∼103 ton-yr for all locations. These results highlight the benefits for employing two detector locations, one at high and one at low latitude
Collaboration among general education and special education teachers: Providing an appropriate education for all students
No full textThe primary purpose of this quantitative study was to investigate whether special education and general education teacher perceptions of collaboration, leadership, and efficacy beliefs influenced student performance on STAAR. Quantitative data were collected using a Qualtrics survey consisting of 56 items regarding special education and general education teacher perceptions of collaboration, leadership, and efficacy beliefs, as well as demographic questions (Qualtrics, 2022). State of Texas Assessments of Academic Readiness (STAAR) data from the Texas Education Agency (TEA) public website was also collected for 40 public school districts in Region 2 using STAAR Performance Reports and Group Summary Performance Level Reports (eMetric, 2023; TEA 2019, 2021, 2022). The logistic regression models utilized throughout this study did not detect a significant connection between efficacy beliefs, instructional leadership support, and collaboration on special education student achievement based on the 2023 STAAR Reading and Mathematics Assessments (eMetric, 2023). Despite prior research indicating a link between teacher collaboration, leadership, and efficacy beliefs on student performance, the findings of this study did not yield that of previous research.Educational Leadership, Curriculum & InstructionCollege of Education and Human Developmen
Methane emissions from southern Texas estuaries
No full textDataset ranging from May 2018 to May 2021 of methane emissions from southern Texas estuaries
Reef design influences habitat provision on a restored oyster reef
No full textHabitat restoration efforts are often limited by cost, making it important that
available funds are used efficiently and effectively to achieve desired restoration
goals. In this study, we evaluate habitat provision for oysters and motile epifauna
on restored oyster reefs in a northwestern Gulf of Mexico estuary constructed
with discrete high vertical relief (~0.6m“reef mounds”) or continuous low vertical
relief (<0.08 m “reef flats”). Habitat provision on reef mounds exceeded that on
reef flats within one month of construction and supported 0.75x higher oyster
density, 2x higher motile epifauna biomass, and 3.6x higher motile epifauna
density one year after construction. Oyster density on reef mounds remained
relatively high throughout the study period, with ~2x higher oyster densities than
reef flats 18 months after construction and ~1.5x higher oyster densities by the
end of the study. Both reef mounds and reef flats increased oyster and epifaunal
densities compared to unrestored areas. Although on-reef oyster densities were
higher on reef mounds than reef flats, the total restored oyster areal density and
volumetric density was higher in restored reef flat areas, primarily because the
restored flats area had no gaps within its restoration boundaries. Our findings
have practical value for better predicting restoration outcomes and achieving
desired restoration goals based on restored oyster reef height, with reef mounds
maximizing on-reef oyster and epifaunal densities and reef flats maximizing the
total number of oysters per area restored or volume of substrate purchased.
Understanding the benefits and tradeoffs between restoration designs will allow
resource managers to improve cost-efficiencies in future restoration projects
Votes, not vows: Do ideological labels predict electoral performance? A look between electorally safe and marginal members
No full textCollege of Liberal Arts; Department of Social Sciences, Political Science Program; Faculty Mentor: Dr. Laine ShayDoes a House member need to worry about electoral ramifications for being too ideologically? This research will investigate the relationship between an incumbent’s electoral performance and ideological extremism (roll call support for their party) — controlling for electoral security, challenger quality, presidential vote, campaign spending, partisan affiliation, and seniority, analyzing results for the 116th Congress. The study produces unexpected findings. Not all incumbents receive a lower vote share for casting more ideologically extreme rollcall votes. In particular, for electorally vulnerable members of Congress, they receive an electoral penalty for being more ideologically extreme. Conversely, ideological extremism has no impact for electorally secure members of Congress. Consequently, this study contributes to the understanding of ideology and electoral accountability today
Understanding hope as experienced by first-generation college students at Hispanic-serving institutions
No full textUtilizing interpretive phenomenological analysis (IPA), this study describes how the phenomenon of hope is experienced by six first-generation college students at South Texas Hispanic-Serving Institutions (HSIs), how student affairs contributed to that hope, and how these students understood the spaces on a college campus relative to their experiences of hope. The culturally engaging campus environment (CECE) model was used as a theoretical framework which allowed for consideration of how the HSI environment engages with students. The study’s findings add to the literature by revealing how hope surfaced from 1) within the individual participants, as it might if were a value, a character trait, or someone’s nature, and 2) within their relationships, with family, friends, colleagues, mentors, staff, and faculty. Furthermore, these hope experiences and interactions took place on HSI campuses and within the purview of student affairs. The implications for HSIs are that they can cultivate cultures of hope, by integrating culturally engaging campus environment tenets, which is valuable to first-generation college students.Educational Leadership, Curriculum & InstructionCollege of Education and Human Developmen
Paws & breathe: A dialectical behavior therapy informed emotion regulation skills group utilizing animal assisted counseling
No full textThe development of depressive symptomology and other social-emotional disorders is common during adolescence (Rapee et al., 2019; van Harmelen et al., 2015). Dialectical Behavioral Therapy (DBT) skills can effectively target a critical factor in social-emotional disorders—emotion dysregulation (Hermosillo-de-la-Torre et al., 2023). Animal-assisted counseling (AAC) can decrease depressive symptomology and accelerate therapeutic rapport (Eaton-Stull et al., 2021; Parish-Plass, 2018). Despite the literature found, there is a lack of research integrating AAC with evidence-based treatment and mental health treatment studies focusing on depression and emotion regulation skills in adolescents. The purpose of this study was to explore the effects of a 6-week DBT-informed skills group using AAC on emotion dysregulation and depressive symptomology in adolescents at a South Texas counseling training clinic. Participants in this study were adolescents aged 13-15 years old (N=5). This study utilized snowball sampling to recruit participants. This was a single-case research design with a pre-treatment baseline phase, a treatment phase, and a post-treatment baseline phase (A-B-A). This single-case research design explored changes in participants’ emotion dysregulation and depressive symptoms throughout the 12-week study. The quantitative analysis utilized examined changes throughout the study, as measured by The Difficulties in Emotion Regulation Scale-Short Form (DERS-SF) and Mood & Feelings Questionnaire-Short Version (MFQ-SV). The results derived from the data indicate that the DBT-informed skills incorporating AAC were effective at decreasing some participants’ emotion dysregulation and depressive symptomology. The treatment effects, while varying in effectiveness, demonstrated that participants who engaged with the professional therapy animal showed improvement in symptomology and dysregulation, regardless of effect size. This finding is particularly noteworthy, excluding the one participant who did not complete treatment. The implications of this study are promising. They support the existing literature that DBT skills and AAC are beneficial for adolescents’ social-emotional state. The findings of this study strongly indicate that an AAC DBT-informed skills group has the potential to create a positive therapeutic environment and increase knowledge of emotion regulation skills.Counseling & Educational PsychologyCollege of Education and Human Developmen
Senator Truan and wife Elvira Truan
No full textSenator Truan poses for a photograph with his wife, Elvira (nee Munguia) Truan