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Carbon Dioxide Leakage from CO₂ Disposal Aquifers
No full textCarbon capture and storage (CCS) is a critical technology for reducing atmospheric CO₂ emissions by storing CO₂ in deep disposal aquifers. However, the long-term effectiveness of CCS remains uncertain due to the potential for CO₂ leakage through low permeability cap rock, faults, and abandoned wells. This study investigates the risks associated with CO₂ leakage from disposal aquifers over extended periods based on numerical simulations using tNavigator. A three-dimensional geological model was developed with realistic reservoir properties, including permeability, porosity, and cap rock integrity. The simulations examined various leakage pathways: (1) through low-permeability cap rock, (2) via faulted reservoirs, and (3) through abandoned wells. CO₂ plume migration, pressure evolution, and trapping mechanisms—including structural, residual, solubility, and mineral trapping—were analyzed over a 1,000-year monitoring period. The results indicate that although the cap rock initially acts as a containment barrier, gradual leakage occurs over extended time periods. Faults, even with low permeability, act as conduits for CO₂ migration, significantly increasing leakage risks. The most severe leakage occurs through abandoned wells, where CO₂ escapes directly into overlying formations, emphasizing the importance of proper well sealing and monitoring. Additionally, pH variations and gas saturation maps highlight regions of CO₂ accumulation and potential environmental impact. These findings challenge the assumption that CCS provides completely secure carbon storage. They underscore the necessity for robust site selection, continuous monitoring, and adaptive risk management strategies to minimize leakage risk
Applications of Multispectral Remote Sensing Techniques to Estimate Suspended Sediment Concentration in Proglacial Lakes Near Kangerlussuaq, Greenland
No full textProglacial lakes along the western margin of the Greenland Ice Sheet act as reservoirs for freshly weathered sediment, which is subsequently transported downstream by braided rivers and deposited in adjacent fjords. This study focuses on a series of interconnected proglacial lakes directly influenced by the Russell Glacier and each other. The primary objective of this project is to estimate sediment delivery and deposition across seven proglacial lakes near the Russell Glacier margin near Kangerlussuaq to identify trends in sediment transport and deposition within this dynamic system. Conducting fieldwork in Arctic regions presents challenges due to high financial costs, hazardous conditions and limited accessibility. Remote sensing has improved accessibility by enabling scientific observations via satellite imagery, facilitating both multi-year and large-scale monitoring. However, the accuracy of remote sensing techniques for estimating suspended sediment concentration (SSC) is often optimized for the specific study areas for which they were developed (Dethier et al., 2020). Additionally, the wide range of existing techniques complicates efforts to identify the most effective for approaches. A key goal of this study is to evaluate multiple remote sensing techniques for SSC estimation and determine which best correlate with field measurements from the study area. During the 2023 and 2024 melt seasons, SSC was measured at lake inlets, outlets, and centers. Techniques from Kavan et al. (2022), Joshi et al. (2023), and Overeem et al. (2017) were applied to Sentinel-2 and Landsat 8/9 imagery to assess their predictive performance. Based on these analyses, a site-specific SSC prediction equation was developed using Landsat 8/9 Near Infrared (NIR) reflectance and field data. Additionally, this study examines spatial and temporal trends in suspended sediment transport during the 2023 and 2024 melt seasons, and explores relationships between predicted SSC and environmental factors such as temperature, precipitation, and proglacial lake connectivity. The findings underscore the need for continued refinement of remote sensing techniques for SSC estimation
Trace Gases and Solar-Induced Fluorescence in the West Coast of the USA
No full textAs global warming and climate change become a greater concern all over the world, scientists and leaders are paying increased attention to these issues. We chose to focus on wildfires because forest fires play a devastating role in emitting large amounts of greenhouse gases (GHGs) and other harmful pollutants. During California’s typical fire season, from April to end of October, Southern California experiences minimum precipitation. Wildfire intensity and frequency peak between August and October, leading to a high Vapor Pressure Deficit (VPD), which in turn reduces photosynthesis activities. To better understand the harmful emissions from wildfires, we utilized satellite data and models. Specifically, we analyzed CO2 data from the OCO-2 satellite, CO and CH4 data from the TROPOMI satellite, CO2 from the CarbonTracker model, and CO from the GEOSChem model. Reduction of photosynthesis activities coupled with increase in biomass burning cause a rise in CO2 concentration as observed by the OCO-2 satellite. The dry season also witnesses increased CO and CH4 levels, linked to intensified biomass burning, as detected by TROPOMI retrievals. The CarbonTracker model captures increased CO2 concentrations, though with slightly lower amplitude. Similarly, the GEOS-Chem model successfully simulates higher CO levels but underestimates the observed enhancements. Using Solar-Induced Fluorescence (SIF) measurements over the Los Angeles (LA) basin via both TROPOMI satellite and the California Laboratory for Atmospheric Remote Sensing (CLARS) observatory, we found SIF provides valuable insights into the area’s wet/dry conditions. Despite CLARS is a ground-based monitoring facility, it effectively captured the increase in trace gas concentrations during the dry season (August – September). A comparison between October in 2020 (extremely dry and intense fires) and October 2019 (relatively dry and milder fires) revealed that SIF is a better indicator of fire intensity than CO2, CO, and CH4. Finally, our study of Pacific North American (PNA) pattern on atmospheric CO2 level revealed that the PNA can modulate atmospheric CO2 concentration. During the positive PNA phase, northwestern (southern and northeastern) parts of the North America showed positive (negative) CO2 anomalies. This finding suggests that mid-tropospheric CO2 anomalies can be caused by the CO2 surface anomalies
Making Sense of Injustice: Exploring How Meaning Search Drives Black Lives Matter Activism Post Police Violence Exposure
No full textExtensive evidence suggests that, in the aftermath of negative events or collective trauma, people tend to pose existential "why" questions and actively search for meaning. This pursuit of meaning has been found to be closely tied to the motivation for activism. While evidence shows that meaning search motivates activism, there is a notable gap in research when it comes to the relationship between meaning search and racial activism. Moreover, there is a dearth of research on the interplay between racial trauma and the search for meaning. In the present study, I examined the effects of police violence images (i.e., White officers using excessive force on Black citizens) on the search for meaning, and attitudes toward the Black Lives Matter (BLM) movement in one study (N = 357). We found that there was no difference in general meaning search among participants between conditions (police violence images vs. neutral police images), and there was no difference in a willingness to engage in activism between conditions. Though, among our exploratory analyses we found that negative affect mediates the relationship between the condition and activism intentions, the condition predicts activism engagement with the presence of moderators, and we found that those searching for meaning are more willing to engage in activism than those not searching. While our main hypotheses were unsupported, our findings overall underscore the emotional significance of racial activism and movements beyond their political objectives
Outcomes of Metabolic and Bariatric Surgery in Populations with Obesity and Their Risk of Developing Colorectal Cancer: Where Do We Stand? An Umbrella Review on Behalf of TROGSS—The Robotic Global Surgical Society
No full textIntroduction: Obesity is a chronic disease associated with increased risk for several cancers, including colorectal cancer (CRC), a leading cause of cancer-related mortality. The majority of CRC cases are associated with modifiable risk factors. Metabolic and bariatric surgery (MBS) is a proven, durable, and successful intervention for obesity. This study aimed to evaluate the impact of MBS on CRC risk through measures of association, such as relative risk (RR) and odds ratio (OR). Methods: A systematic search of PubMed, Scopus, Web of Science, ScienceDirect, and Embase was conducted to identify systematic reviews (SR) and meta-analyses examining the relationship between obesity treated with MBS and CRC incidence. The PICO framework guided inclusion criteria, and three independent reviewers screened articles using Rayyan software. Quality assessment was performed using AMSTAR2. Results: Of 1336 screened articles, 10 SR met inclusion criteria, encompassing 53,452,658 patients. Meta-analyses consistently showed a significant reduction in CRC risk following MBS in patients with severe obesity. Risk reductions were reported by Liu et al. (RR: 0.46, 95% CI: 0.32–0.67, p < 0.01), Chierici et al. (RR: 0.46, 95% CI: 0.28–0.75, p = 0.018), Wilson et al. (RR: 0.69, 95% CI: 0.53–0.88, p = 0.003), and Pararas et al. (RR: 0.56, 95% CI: 0.40–0.80, p < 0.001). Sensitivity analyses supported these findings. For colon cancer, Liu and Chierici both reported an RR of 0.75 (95% CI: 0.46–1.21, p = 0.2444) with significant heterogeneity (I2 = 89%). A trend towards reduced rectal cancer risk (RR: 0.74, 95% CI: 0.40–1.39, p = 0.3523) was noted but limited by fewer studies. Sex-specific analyses revealed protective effects in both sexes, with a more pronounced impact in females (RR: 0.54, 95% CI: 0.37–0.79, p = 0.0014). Conclusions: This umbrella review synthesizes current evidence on the impact of MBS on CRC risk, highlighting a consistent protective association. The findings also indicate a potential risk reduction for both colon and rectal cancer, with a more pronounced effect observed among females compared to males. Given the profound implications of MBS on cancer incidence, morbidity, and mortality, further high-quality, long-term studies are essential to deepen our understanding and optimize its role in cancer prevention and patient care
Following Ocular Changes in United States Optometry Students (FOCUS): Protocol Development and Baseline Data
No full textPurpose: To develop a protocol and present pilot data for the longitudinal study, Following Ocular Changes in United States Optometry Students (FOCUS), which aims to collect comprehensive ocular data over two years in a population of young adults that are known to engage in intense near work. Methods: First year optometry students at the University of Houston College of Optometry underwent baseline measures. The right eye was dilated with 2.5% phenylephrine and two drops of 1% tropicamide. Measurements included cycloplegic autorefraction (Grand Seiko), biometry (LenStar), optical coherence tomography (OCT) and OCT angiography (OCTA, Spectralis), and ocular aberrations (COAS HD). Participants were classified into refractive error groups. OCT scans were analyzed for retinal and choroidal thickness, optic nerve head parameters, superficial and deep vascular density, and foveal avascular zone area. Results: Participant age was 23.12 ± 1.64 years (N = 86), with 65 females and 21 males. Mean right eye SER was -2.58 ± 3.13 D, which consisted of 6 hyperopes (7%), 19 emmetropes (22%), and 61 myopes (71%). Choroidal thickness was significantly associated with SER (P < 0.001). Bruch’s membrane opening area was 1.95 ± 0.50 mm and anterior lamina cribrosa depth was 411.28 ± 95.80 µm. Global minimum rim width was 364.23 ± 63.41 µm. Foveal avascular zone area and perimeter were associated with axial length (P < 0.05 for both). Optic nerve head metrics demonstrated variations by sector and eccentricity. Higher order root mean square wavefront error for a 5 mm pupil was 0.22 ± 0.08 µm. Conclusion: A protocol for the FOCUS study was developed and pilot data were collected. Limitations were identified and will be addressed in future data collection. Notable changes include increased recruitment efforts, additional measures, including intraocular pressure and peripheral refraction, and collection of subjective and objective behavioral data. A future direction is to expand the study into a multi-center collaboration involving optometry students from institutions across the United States to more accurately reflect the nation’s demographic diversity. Ultimately, findings will contribute to a better understanding of adult onset and progression of myopia and provide guidance in clinical decision-making regarding myopia interventions
Celebrating Diversity in Urban Areas: Embracing Current Events at the Intersection of Social Consciousness and Restorative Practices
No full textBackground: Students in urban areas experience great diversity in schools. The data state that 27% of urban students identify as White, 22% as Black, 37% as Hispanic, and 7% as Asian American-Pacific Islander. It is undeniable that diverse, urban demographics play a role in the development of children. Despite the diversity amongst urban students, one alarming trend is the rising amount of hate crimes within a K-12 setting. In 2020, about 1.3 million students, ages 12 to 18, were bullied for their race, religion, national origin, disability, gender, or sexual orientation. Purpose: The purpose of this self-study was to examine the process to create a curriculum that is reflexive in nature, authentically connected to current events, and includes discourse as a generator for social consciousness in students via restorative practices. Using John Dewey’s theory of social consciousness, the researcher examined how educators can foster social consciousness through current events with a restorative lens. Research Question: How can an administrator create curriculum which utilizes current events with a restorative practice lens to foster social consciousness in students? Method: To maximize the data sets that were collected throughout this study, the researcher included a field journal and self-questioning. The field journal documented the steps required to create such a curriculum, as well as the moments of ease or challenges faced by the researcher. When it came to self-questioning, the researcher conducted three self-interviews to reflect on key moments in the process. The self-interviews occurred before the beginning of the journey of curriculum development, the mid-point of the curriculum development process, and after the research was completed and the curriculum was developed. Findings: The researcher identified the restorative elements of the curriculum as the highlight. Drafting questions for students to engage in discourse and literacy with a restorative lens allowed the researcher to feel a sense of pride in the curriculum. The ethical considerations regarding the curriculum material were the largest challenge. The researcher discovered that locating current events in the last five years with reliable publishers was a lengthier process than initially expected, exceeding the planned allocated time. Conclusion: The self-study determined that a literacy-based restorative curriculum rooted in recent and reliable current events is a catalyst for social consciousness in students. The researcher proposes that administrators and teachers leverage the curriculum as a source of restorative practice in secondary schools as a way to decrease hate speech amongst urban students
A Three-Part Study to Enhance Understanding of Social Behavior and Identity Preferences of Autistic Adolescents
No full textBackground: As knowledge of autism expands, so does our understanding of the behaviors utilized by many autistic individuals to “fit in,” or camouflage their autistic traits. Much is unknown about camouflaging, including how race and/or ethnicity and the strength of racial/ethnic identity influence camouflaging among autistic adolescents. Issues related to neurodivergent identity development are an emerging area of investigation, more specifically terminology preference amongst autistic adults. However, it is unclear whether adolescents with autism have similar views regarding terminology use and how strongly they feel about issues related to language use. These questions may have important implications for identity development in neurodiverse adolescents. Purpose: This three-study dissertation enhances understanding of social behavior and identity preferences of autistic adolescents. The first study examined whether race/ethnicity, specifically being Black/African American (AA), impacted camouflaging rates for adolescent males with autism. The second study explored how other factors, mainly strength of racial/ethnic identity impacted camouflaging rates for adolescents with and without autism. The third study investigated adolescent terminology preferences compared to parent preferences. Methods: Data for all three studies were collected via SPARK Research Match beginning in Spring 2023. English-speaking, adolescents between ages 13-17, living in the United States, and their parents were invited to participate. Results: Results of study 1 indicated no significant differences in self-reported autism traits or camouflaging between Black/AA and White males with autism. Results of the hierarchical regression in Study 2 indicate that strength of racial/ethnic identity does not predict variance in CAT-Q scores. Descriptive statistics and independent sample t-tests in Study 3 highlight variation in terminology and strength of preferences of autistic adolescents, as well as a significant between-group difference in strength of preference for person with ASD/autism F(1,295) = 88.88, p< .001 with parents expressing stronger preference for person-first language. Limitations include potential issues related to sample size, lack of representation of broader autism community, and appropriateness of measures. Conclusion: Understanding identity development, terminology preferences, and factors that influence camouflaging amongst autistic individuals is complex. It requires the inclusion of as many voices as possible including children and adolescents, as their experiences are crucial to furthering our understanding of development of autism across the lifespan and across cultures. Taken together, these three studies contribute to the literature by providing insights into adolescent experiences with camouflaging and preferences for identity language use
Melatonin Use Among Children in Foster Care
No full textPoor sleep is something many children struggle with, but research findings show that children in foster care (FC) have a higher frequency of sleep problems than the general population. Though melatonin is increasingly used as a sleep aid in child populations, including children in FC, data regarding the effectiveness and safety of melatonin and how use might differ between children in FC and the general community are limited. This study sought to understand and compare characteristics of melatonin use between children in FC versus the general community. A total of 292 foster caregivers (n=128) and biological parents (n=164) of children aged 4-12 years (M=7.35, SD=2.66) who took melatonin in the past 30 days completed an anonymous online survey via Qualtrics. The survey included questions regarding melatonin's perceived effectiveness and safety as well as sources of recommendation, and administration practices. After controlling for child race and ethnicity, caregivers of children in FC were more likely to report talking to a medical professional before administering melatonin (71%) than biological parents (51%; B=-0.868, Wald=10.93, p<.001). Children in FC were more likely to use melatonin everyday (44%) compared to community children (19%; B=1.092, Wald=21.71, p<.001). There were no significant group differences in rates of melatonin's overall effectiveness. The most frequently reported adverse effect was the child believing they could not sleep without melatonin, which was higher among FC children (20%) than in community children (10%; B=0.902, Wald=5.913, p=.015). Findings suggest that children in FC are given melatonin more regularly than community children, though parent perceptions of effectiveness did not differ. Overall, adverse effects were low, though state-dependent learning around sleep may be more of a concern for children in FC than children in the community, which could have adverse long-term impacts on sleep health. Future research using longitudinal designs and including child-report and objective sleep measures is needed.Psychology, Department ofHonors Colleg
Mitochondrial Function in T-cells: The Impact of Cardiorespiratory Fitness and Body Fat in Men and Women
No full textWe investigated whether T-cell mitochondria differed in women and men categorized by VO2max and %body fat. Participants were 9 women and 17 men aged 20-39 years. Participants donated blood, had a DEXA scan to determine body mass/composition, and completed a VO2max test. Briefly, participants cycled on a bicycle at increasing resistance, until volitional exhaustion. Heart rate and gas exchange were recorded. Leukocytes isolated from blood were stained with dyes and antibodies to identify T-cell mitochondria. Data were analyzed separately between men and women by independent T-tests to assess differences in T-cell mitochondrial mass and function between those with high and low VO2max and between those with high and low %body fat. Compared to women with lower VO2max values (mean: 27.2ml/kg/min) women with higher VO2max values (mean: 33.0ml/kg/min) trended towards greater ratio of functional mitochondria (t=-2.46, p=.073) but did not differ in T-cell mitochondrial mass (t= -0.21, p=.837). Men grouped by VO2max (high mean: 45.1ml/kg/min, low mean: 31.6ml/kg/min) did not differ in either variable. However, compared to men with higher %body fat (mean: 26.4%), men with lower %body fat (mean: 15.5%) trended towards a greater ratio of functional mitochondria (t=1.81, p=.095). They did not differ in mitochondrial mass (t= -0.01, p=.99). Women categorized by %body fat also did not differ in either measure. Data collection is ongoing.Health and Human Performance, Department ofHonors Colleg