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Feasibility of Switching from Solvent to Aqueous Cleaning of Oxygen Gauges
Full text linkThis study presents the development of a cyclic vacuum cavitation cleaning system designed to remove hydrocarbon contamination from Navy-supplied Bourdon tube oxygen gauges to below 5 ppm in the final rinse. The objective of this study was to identify the most effective aqueous cleaning method and establish a reliable quantification method for residual hydrocarbons to eventually compare the aqueous cleaning method to the existing method using CFC-113. A series of preliminary experiments was performed to evaluate cleaner performance, evaluate analytical sensitivity, and refine solvent
handling and system design.
A simplified quantitative structure property relationship (QSPR) model was developed to predict thermochemical properties of organic molecules solely based on molecular formula. Twelve commercial surfactant cleaners were characterized by measuring their surface tension, density, and pH, and their cleaning effectiveness was tested using hydrocarbon-based soils in capillary tubes with cyclic vacuum cavitation. Fluorescent analysis coupled with ImageJ software was evaluated as a method for quantifying hydrocarbons and assessing analyst variability. Quantification of hydrocarbons was further explored using Raman and Fourier Transform Infrared (FTIR) spectroscopy. Solvent purification and material compatibility tests were performed to prevent contamination from experimental components and improve baseline cleanliness of the solvents.
The QSPR showed strong correlations between predicted and literature lower heating values (LHV), which make it a practical tool for rapid thermochemical estimation. Capillary cleaning results showed cleaners with a lower surface tension and high pH were more efficient at cleaning hydrocarbons. Fluorescent analysis lacked the sensitivity required for quantitative measurements for our study but can be used as a screening method for hydrocarbon residue. Raman spectroscopy was not sensitive enough to measure below 5000-ppm, while FTIR spectroscopy was successfully calibrated to measure hydrocarbon levels down to approximately 48 ppm, though further purification is needed to reach the 5-ppm target.
This work establishes a foundation for the design of a cyclic vacuum cavitation cleaning system necessary for the final comparative study between aqueous and CFC-113 cleaning processes for oxygen systems
Microbiome Composition and Community Structure in Soil Sediments of Lake Raven and Lake Conroe
Full text linkFreshwater microbes are essential to lake ecology, acting as indicators of both
natural and human-induced disturbances because of their quick response to
environmental changes, and contribution towards sustaining the structural and functional stability of aquatic ecosystems. Lake Conroe is a 21,000-acre reservoir that serves as the reserve drinking water supply for the city of Houston and provides a wide range of recreational opportunities, while Lake Raven is a 203-acre reservoir located in Huntsville State Park and is also used for a variety of recreational activities. The objective of this study is to compare the microbiome composition and diversity between the two lakes. In
this study, it was hypothesized that (i) soil sediment samples collected separately from active and inactive sites of Lake Conroe and Lake Raven exhibit different levels of alpha diversities, and (ii) soil sediments collected from correspondingly active and inactive sites of the two lakes exhibit different levels of beta diversities in all pairwise comparisons of bacterial community. A total of 36 soil sediment samples were collected from the two lakes and stored at -80˚C. Bacterial DNAs were extracted from these soil samples and V3-V4 regions of the 16S rRNA gene were amplified by polymerase chain reaction. Metagenomic sequence library was prepared, and the DNAs were subsequently sequenced using NovaSeq 6000 sequencing. Analysis was performed on Mothur-miseq SOP in Galaxy platform, and taxonomic classification was assigned using RDP (Ribosomal Database Project classifier). Results reveal that the microbial community structures at the two study sites share some common genera including Acidothermus, Aquisphaera, Methylocystis, Mycobacterium, Anaeromyxobacter, Nocardioides,
Bradyrhizobium, Gemmata, Streptomycetes and Haliangium, but differ in the
composition of several unique genera. The observed microbial diversity seems to be associated with metabolic specializations due to anthropogenic activities like recreational activities. Within-lake variations seem to be as a result of human disturbances and stress. Lake-level differentiation suggests physicochemical differences between the two lakes.
Future studies in complete metagenomic analysis will provide insights to identify exact species and their annotated gene functions from these corresponding sites. An analysis of physiochemical parameters of soil sediments and water including pH, levels of dissolved oxygen and solids, temperature would be necessary
MIRRORS IN THE CLASSROOM: EXAMINING ETHNIC/ RACIAL DIVERSITY PATTERNS AMONG TEXAS PUBLIC SCHOOL TEACHERS AND STUDENTS: A MULTI-YEAR DESCRIPTIVE ANALYSIS
Full text linkABSTRACT
Hunter, Sherrhonda S., Mirrors in the Classroom: Examining ethnic/racial diversity patterns among Texas public school teachers and students: A multiyear, descriptive analysis. Doctor of Education (Educational Leadership), December 2025, Sam Houston State University, Huntsville, Texas.
Purpose
The purpose of this traditional dissertation was to describe the racial/ethnic demographic characteristics of students and teachers in Texas public schools. The first specific purpose was to describe the ethnic/racial demographic characteristics of students and teachers in Texas public elementary schools for the 2019- 2020 through the 2023-2024 school years. A second purpose was to determine the ethnic/racial demographic characteristics of students and teachers in Texas public middle schools for the 2019-2020 through the 2023-2024 school years. A third purpose was to identify the ethnic/racial demographic characteristics of students and teachers in Texas public high schools for the 2019-2020 through the 2023-2024 school years. The final purpose was to examine the degree to which trends might be present in the ethnic/racial membership of students and teachers in Texas public elementary, middle, and high schools over a five-year time period (i.e., 2019-2020 through 2023-2024).
Method
For this analysis, a longitudinal descriptive research design was utilized. Archival Texas Academic Performance Report data from the Texas Education Agency were acquired for Texas public elementary, middle, and high schools for the 2019-2020 school year through the 2023-2024 school year. Participants were teachers and students in Texas public elementary, middle, and high schools.
Findings
The ethnic/racial composition of Texas public school teachers and students over the span of five school years (i.e., the 2019-2020 school year through the 2023-2024 school year) varied. The findings revealed persistent disparities between the demographic compositions of teachers and students across elementary, middle, and high school levels. While the student population in Texas has become increasingly diverse, with growing proportions of Hispanic, Black, and Asian students, the teaching workforce remains predominantly White, with White teachers consistently overrepresented relative to the student populations they serve. Hispanic and Black teachers' representation has shown a modest increase, yet remains disproportionately low compared to the large and growing populations of Hispanic and Black students. Asian teachers, although the smallest group, have experienced slight growth, but continue to be underrepresented relative to Asian student enrollment.
The demographic mismatches emphasize ongoing challenges in recruiting and retaining teachers of color and reveal systemic barriers that contribute to the slow pace of workforce diversification. The results align with existing literature documenting the importance of teacher diversity for improving student achievement, social-emotional development, cultural competence, and overall school climate, particularly for students of color. Furthermore, the findings support theoretical frameworks of social closure and homosocial reproduction, reflecting how deep-rooted educational program practices reinforce inequalities in teacher representation
THE RELATIONSHIP BETWEEN SHAME, SUBSTANCE USE, AND LGB IDENTITY DEVELOPMENT
Full text linkThe disproportionate prevalence of substance use disorders among lesbian, gay,
and bisexual (LGB) individuals compared to their heterosexual counterparts emphasized the need for research exploring contributing factors. A review of the literature highlighted the history of substance use disorders, the historical pathologization and same-sex attraction, and the effects of shame. Grounded in Brene Brown’s Shame Resilience Theory (SRT), this study investigated the relationship between substance use, external shame, and LGB identity development through a quantitative correlational research
design.
The final sample included 177 adult LGB participants recruited through
convenience and snowball sampling. Participants completed the Adult Substance Abuse Subtle Screening Inventory-4 (SASSI-4), the Other as Shamer Scale-2 (OAS-2), and the Lesbian, Gay, and Bisexual Identity Scale (LGBIS). Descriptive statistics, Pearson correlations, and independent samples t-tests were conducted. External shame was significantly and positively correlated with four dimensions of LGB identity development: Acceptance Concerns, Identity Uncertainty, Difficult Process, and Identity Superiority. Additionally, a statistically significant positive relationship emerged between Acceptance Concerns and participants’ acknowledgment of substance misuse and its
consequences. Participants classified as having a high probability of a substance use disorder reported significantly greater distress in the identity development process compared to those in the low probability group. The study’s completion provided further insight into the results, informed the discussion, and guided future recommendations
HOME LANGUAGE AND SPECIAL EDUCATION ENROLLMENT: A MULTIYEAR TEXAS INVESTIGATION
Full text linkPurpose
The purpose of this dissertation was to determine the extent of differences in
special education eligibilities between native English speakers in Texas public
elementary schools and students who have a home language other than English in Texas
public elementary schools. Research studies about Emergent Bilingual students are
prevalent, as well as identification and disproportionality of special education
identification, but only limited empirical evidence is available about how cultural and
linguistically diverse backgrounds affect the special education identification process.
Findings from this dissertation may constitute vital information to the literature on
Emergent Bilingual students who may need additional services through special education.
Findings from this dissertation could be useful to school leaders in fast-growth areas to
respond to the culturally and linguistically diverse needs of these students.
Method
A descriptive, non-experimental study with causal-comparative methods was
present in this investigation (Johnson & Christensen, 2014). Archival data were collected
from the Texas Education Agency Public Education Information Management System for
the 2019-2020 school year through the 2024-2025 school year.
Findings
Analysis of the data in all six school years studied revealed statistically significant
lower percentages of Emergent Bilingual students were identified for special education
iv
services. Students who speak another language at home in Texas are more likely to be
underidentified for special education than their native English-speaking peers and will
not be identified in all areas of eligibility, either. Students in fast growth school districts
and who are Emergent Bilingual are more likely to be identified as needing special
education services but are still identified at a statistically significant lower rate than their
native English speaking peers.
Implications
The need for continued training of educators and service providers to bridge the
gap to students and families of culturally and linguistically diverse backgrounds is made
apparent in the descriptive analysis of the data concerning Emergent Bilingual students in
Texas. Students who are not native English-speaking are underidentified and
overidentified in special education disability types when compared to native Englishspeaking peers around the State of Texas, who has the highest number of Emergent
Bilingual students in the nation
Bounty: Beyond the Voyage [Review]
Full text linkA book review.... Pearson, Julie. 1989. Bounty: Beyond the Voyage. Upton upon Severn: Trusson Publications
The Role of Institutional Mentors in the Lives of First-year, First-generation Developmental Students at a Select Four-year University and Two-year Community College
Full text linkThis study investigated the role of TRIO Student Support Services (SSS) mentors
in the lives of first-year, first-generation college students (FGCS) who also placed into at least one developmental course as they transitioned to higher education. This population of students faces multiple compounding barriers to success as they enter higher education; therefore, it is important to learn about the unique needs of this population and the ways in which mentors can help these students successfully navigate the challenges of higher education. Because most studies focus on only one of the three characteristics
(first year, first generation, or developmental), this study addressed a gap in the literature by considering the combined challenges of students who fall into all three categories.
This qualitative study employed semi-structured interviews with ten participants, four from a four-year degree-granting university and six from a two-year community college. Interview questions sought to learn about the role of TRIO SSS mentors in participants’ (a) academic transitions to higher education and (b) social and emotional transitions to higher education. Participants’ responses to the interview questions revealed eight themes: five related to participants’ academic transitions to higher education and three related to their social and emotional transitions. Findings were used to make recommendations for practice and discuss implications for further research. The findings of this study may help to inform best practices for mentoring this unique population through TRIO SSS or other mentoring structures and models
The Burdens We Carry: A Transcendental Phenomenological Exploration of Black Professional Counselors Working with Clients Who Experienced Racial Trauma
Full text linkRacism has impacted the lives of many people in America. As a result, racism has created emotional and mental wounds for people of the Global Majority, leading to what we know today as racial trauma. Professional counselors have an ethical duty to recognize, address, and intervene to best support and help clients heal from the impact of racism and racial trauma. Although there is extensive literature about racial trauma, a lack of literature centers on the experiences of mental health professionals addressing racial trauma in counseling. Therefore, the purpose of this qualitative study was to explore the experiences of Black professional counselors working with clients who experienced racial trauma. The researcher used Critical Race Theory (CRT) and Black Critical Theory (BlackCrit) as a framework for this transcendental phenomenological study. Additionally, the researcher used semi-structured interviews to explore the experiences of 10 Black professional counselors. Five themes emerged from the results of the study: 1) Bearing Witness, 2) Collective Woundedness, 3) Barriers and Challenges, 4) Healing-Focused Approaches, and 5) Counselor Preparation and Development. Discussion of the findings, implications for the counseling profession, counselor education, and recommendations for future research are included
TEACHERS’ PERCEPTION OF GRADE 7 MATHEMATICS CURRICULUM
Full text linkThis qualitative collective case study examined Grade 7 mathematics teachers’
perceptions of teaching the Texas Essential Knowledge and Skills (TEKS) curriculum and their experiences of students’ learning the TEKS. Guided by Remillard and Heck’s Enacted Curriculum Framework, the study sought to understand how teachers interpret, implement, and reflect upon teaching the state curriculum.
Participants included Grade 7 mathematics teachers from junior high campuses
within a Houston Texas metropolitan area district. Data was collected through semistructured interviews, and curriculum artifacts. A thematic analysis approach was employed, with data coded and organized to capture both individual teacher perspectives and cross-case patterns.
Findings revealed that teachers valued the TEKS for providing a structured
progression of mathematical content but expressed concerns about the breadth of standards and the pacing required. Teachers in both contexts reported that the density of the curriculum often limited opportunities for deeper conceptual exploration. Participants also emphasized the persistent academic gaps evident in the transition from Grade 6 to Grade 7, noting that many students required significant support to engage with grade level expectations. Participants experienced emotions, including frustration, persistence, and reduced confidence, in themselves as well as their students when navigating challenging material. Despite these barriers, teachers identified collaborative planning, targeted interventions, and the use of digital resources as strategies to mitigate gaps and promote student engagement.
Conclusions indicate that while teachers view the TEKS as necessary for
maintaining instructional alignment, the curriculum’s scope contributes to tensions between coverage and depth. Implications include the need for professional development focused on pacing flexibility, strategies for bridging prior knowledge with new content, and supports that address the academic dimensions of student learning. This study underscores the importance of incorporating teacher voice in curriculum development and highlights the potential of enacted curriculum research to inform future professional
development and instructional practice
Visualizing the Manhattan Curve
Full text linkThe modern field of geometry is heavily based on topological structures called manifolds. We focus specifically on 2-dimensional manifolds which we call surfaces. We can add an additional structure to a surface that lets us discuss geometric quantities such as distance and area. If a surface has negative Euler characteristic, which is the most common case, then it will admit a finite area hyperbolic structure. The main surface we will be focusing on in this thesis, the thrice-punctured sphere S₀,₃, is particularly interesting because it has exactly one finite area hyperbolic structure that can be placed on it. As it turns out, hyperbolic structures are a subset of a broader class of geometric structures known as convex real projective structures. There are uncountably many convex real projective structures that can be placed on S₀,₃, and in this thesis, we focus on a specific family of convex real projective structures that are generated by reflecting along edges of a triangle inside a strictly convex subset of the real projective plane. A numerical quantity can be assigned to each of these convex real projective structures, that measures how “chaotic” the structure is. This value is called the Hilbert entropy. A finer comparison of any two of these convex real projective structures can be obtained through a graph known as the Manhattan curve and characterized by a dynamical quantity called the correlation number. In this thesis, we wrote a program that approximates the graph of the Manhattan curve and estimates the correlation number for any two convex real projective structures in this specific family