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How Likely Is a Repeat of the February 2021 Winter Storm Event in Texas, Really? An Impact-Driven Analysis of Compound Cold-Weather Variables in the Context of the Changing Climate
No full textThe extreme cold that led to the failure of the Texas electrical grid in February 2021 has been extensively analyzed in terms of both its likelihood and its predictability. Other authors have pointed out that the severity of its impact ��� power lost to 4.5 million households representing 10 million people for roughly 3 full days ��� is disproportionate to the severity of the cold. Because the return periods of individual extreme weather variables did not correlate with the extreme impacts experienced, we analyzed combinations of cold-weather variables known to affect residential heating demand, electrical generation, and fuel supply. We evaluated these combinations using cold-weather indices which include multiple variables and copulas which combine individual variables.
We weighted temperatures by the population of the metropolitan area in which they occurred to reflect their impact on the electrical grid and adjusted these temperatures to reflect the changing climate of Texas. We found that the conditions experienced at the time of failure, February 15th, 2021, at 2am Central Time, could reasonably be expected between every 3 and 18 years, with the most extreme combination being low temperatures and time spent at or below freezing. After scaling past temperatures to reflect a warming climate, this combination has been more extreme in Texas four or more times over the past 80 years than what was experienced when the electrical grid was not able to produce enough electricity to meet demand for it.
Cold-weather conditions were additionally analyzed over the locations where these generation resources and their fuel supply had the highest failure rates. We found significant differences in the likelihood of the February 2021 conditions both in individual variables and combinations.
Wind power was reduced by turbine icing and was unable to restart for over a week. Using freezing duration following icing conditions for most stations in a cluster resulted in return periods which seemed to align with the impacts of this storm, yet still resulted in the turbine icing component of this interconnected failure being the least likely aspect to occur again
Investigating Fifth Grade Teachers��� Implementation of ESL Instructional Strategies in Literacy-Infused Science Instruction
No full textThe purpose of this study was to investigate whether there is a significant difference in the time allocation of ESL instructional strategies between the treatment teachers who received literacy-infused science (LIS) curriculum accompanied virtual professional development (VPD) on such strategies as an intervention and control group of teachers who did not receive the VPD intervention. I further explored teachers��� perceptions of the impact and challenges of English as a Second Language (ESL) instructional strategy implementation in their science teaching practices and their students��� responses to the strategies.
To examine the differences in fifth-grade science teachers��� time allocation in their use of ESL instructional strategies between treatment and control groups, a low-inference observational instrument, Pedagogical Observation Protocol (POP), was used. Treatment teachers received bi-weekly VPD sessions provided through Project LISTO (Literacy-Infused Science Using Technology Innovation Opportunity, Grant Award No. U411B16001; Lara-Alecio et al., 2013), including a series of scaffolding strategies that benefit teachers��� professional growth as well as their students��� learning outcomes. A total of 14,332 rounds of observation clips were collected from 98 in-service science teachers who were randomly assigned to treatment and control conditions across Texas during the 2018-2019 academic year. Results revealed a statistically significant difference in 7 out of 9 strategies between treatment and control group teachers in utilizing ESL instructional strategies in science classrooms. Treatment teachers significantly used more strategies learned in VPDs than the control group of teachers. To further explore the perceived impact of ESL instructional strategy implementation, semi-structured focus group interviews were conducted for treatment teachers at the end of the school year. The results of the thematic analysis indicated a positive perception of using ESL strategies in science classrooms in terms of enhancing teachers��� quality of instruction and self-confidence as well as students��� science learning interest and literacy development. Therefore, this evidence supported that teachers��� instructional practice and student support were positively impacted by allocating a variety of instructional time toward ESL strategies. However, teachers encountered the challenges such as time constraints and technological issues while implementing ESL strategies might potentially lead to less time allocation in certain strategies
Neoconservatives and Taiwan: Adherents of Conservative Precedent or Advocates for Liberal Interventionism?
No full textDuring the 1990s neoconservatives grew concerned over a burgeoning People���s Republic of China (PRC) threatening the newly democratic government of Taiwan. They wanted the United States to bolster Taiwan���s standing in the international community, commit to defend Taiwan, end strategic ambiguity, prevent further entrenchment of the PRC in international organizations, and push for closer if not official relations between the United States and Taiwan. Neoconservatives frequently employed Wilsonian rhetoric to shore up support for Taiwan. Despite this liberal notion, their foreign policy positions and thinking built on the likes of the China Lobby and New Right. By analyzing neoconservative viewpoints on U.S. policy towards Taiwan one can see how evolved earlier conservative positions despite accusations that they carried on liberal tenets in foreign policy
Underexplored Aspects of Host Finding and Host Acceptance in Parasitoid Wasps
No full textParasitoids use sensory cues, such as olfactory infochemicals, that can be emitted directly by their potential herbivore hosts or plants as a damage response to herbivory to locate potential hosts for oviposition. Despite intensive studies on interactions between parasitoids and their host, certain aspects of chemical communication of the interaction still need to be explored. This study aimed to study the different understudied aspects of odor-mediated host finding and acceptance response of two parasitic wasps (Hymenoptera: Braconidae) with varying degrees of host specificity, Microplitis croceipes (Cresson) (specialist) and Cotesia marginiventris (Cresson) (generalist), integrating multiple tools (analytical, behavioral, electrophysiological). These aspects include the use of plant volatile to determine the parasitism status of damaging hosts, parasitoid���s use of host cuticular composition as cues for host acceptance, and the influence of associative learning of host-related odor in the odor-mediated flight behavior of specialist parasitoids.
The existing literature on the chemical ecology of host selection behavior of parasitoid wasps was discussed, the understudied aspects were identified, and a rationale for the study was provided. Behavioral bioassays were conducted to test the ability of specialist M. croceipes to utilize plant volatiles as host-discrimination cues and found that parasitoids can discriminate and show a preference for volatiles from plants infested by unparasitized hosts over volatiles from plants infested by parasitized hosts and was mediated by the alteration in plant volatile emission due to infestation by parasitized hosts. Behavioral and electrophysiological studies were performed to evaluate the role of host cuticular composition in mediating host recognition and acceptance behavior of M. croceipes and C. marginiventris and reported that specialist parasitoids are more dependent on host-specific kairomonal cues than generalist during host acceptance. The effect of associative learning on the odor-mediated flight behavior of M. croceipes was evaluated by performing a wind tunnel bioassay using two host-related compounds, ��-pinene, and ��-farnesene, and found that odor learning results in enhanced and directed upwind flight towards the learned odors. Results from this dissertation have contributed to our understanding of the understudied but essential aspects of semiochemical-mediated behavior and foraging strategies employed by parasitoids during odor-mediated host findings
Consumer Food Waste While Dining Out: An Examination of Theory of Planned Behavior, Habits, Empathy, and Mindfulness
No full textThis dissertation explores behavioral intentions behind consumer food waste in the dining-out context, leveraging the Theory of Planned Behavior (TPB). It incorporates habits and empathy as preliminary factors influencing consumers��� intentions. Additionally, it examines the moderating role of mindfulness on food waste tolerance, thereby extending the traditional model. The sample consisted of 633 participants who have dined outside of their home at least once in the past 6 months. By employing Structural Equation Modeling (SEM) and path regression analysis, the study examines four distinct models, highlighting the interplay between subjective norms, attitudes, perceived behavioral control, and external factors such as empathy and mindfulness on food waste intentions.
Significant findings emerged from the models, indicating that empathy significantly impacts food waste intentions through attitudes, perceived behavioral control, and habits, while mindfulness moderates the empathy-intentions relationship, particularly influencing how empathy affects subjective norms and attitudes. These findings aim to offer deeper insights into the psychological underpinnings of food waste, providing a nuanced understanding of how individual differences and cognitive processes contribute to diners' propensity for food waste.
Implications of this research stretch beyond theoretical contributions, offering actionable insights for the hospitality industry and other sectors to enhance operational efficiencies, promote environmental sustainability, and foster corporate social responsibility. The study underscores the importance of targeted interventions and the potential of mindfulness and empathy in shaping consumer behavior towards food waste.
The research contributes to the literature by extending the TPB framework, introducing novel moderators, and underlining the significance of psychological factors in understanding and mitigating consumer food waste. Future research directions are proposed to further explore these dynamics and their practical applications across different contexts and cultures
A Deep Learning-Based Methodology to Re-Construct Optimized Re-Structured Mesh from Architectural Presentations
No full textDuring the mid���20th century, the emergence of novel technologies presented a paradigm shift for human intelligence. Computers, in particular, became instrumental tools for designers and architects, enabling the creation of intricate systems with freeform structures. These computers were capable of generating the final shape of designs by employing predetermined algorithms. Nevertheless, the prevalence of intricate freeform constructions is a notable characteristic of modern architecture. The design and calculation of these forms pose a complex challenge, as they deviate significantly from the original target industries in terms of aesthetics, statics, scale, and manufacturing technologies. While these structures may be intricate and, in some instances, praiseworthy, their architectural application necessitates a distinct approach. The formation of novel forms, shapes, and relationships within architectural design compositions can manifest creativity, leading to the exploration and discovery of innovative notions. Architects and designers are, therefore, inclined towards circumstances in which disparities hold significance. Architects may employ or adapt preexisting shapes as a foundation for their design endeavors. Architects draw inspiration from a particular image and integrate the associated notion into their design process, resulting in a more innovative architectural building. Current methodologies enable the meticulous hand alteration of forms through the utilization of documents or photographs. The proliferation of Machine Learning technology is augmenting architectural responsibilities, enabling swift and inventive results, expediting the design process, and developing a forward-looking approach to adjust and retrace actions instantaneously. The objective of this study is to assess the viability and accuracy of incorporating machine learning capabilities into defining an algorithmic-based methodology, with the goal of enhancing the design creativity process in architecture. This will be achieved through the utilization of image-to-mesh 3D reconstruction deep learning techniques, specifically applied to complex, irregular architectural structures. Additionally, a generative mesh optimization algorithm will be employed to generate a customizable mesh surface that can be further manipulated, paneled, and subjected to morphological operations
Improved Whitecap Quantification and Prediction Using Shipboard Remote Sensing and Machine Learning
No full textWhitecaps generated by wave breaking and air entrainment can be classified as active (stage A) or residual (stage B). Discrimination and measurement of each stage individually are essential for accurate parameterization of air-sea interaction processes, but conventional methods used for separation in visible images are subjective. This study provides a novel method to identify whitecap stages based on visible imagery using particle image velocimetry (PIV). A linear relationship was established between the lifetime of stage A and the timescale of averaged velocity. This novel method characterizes stage A whitecap lifetime using whitecap velocity and provides an objective approach to separate whitecap stages.
To estimate active whitecap fraction, we introduced a pipeline for active whitecap fraction measurement. In this pipeline, a new horizon detection method is developed to stabilize and rectify images and a deep learning model based on U-Net is trained and validated to identify and extract active whitecaps. The model is applied to 48 hours of video footage collected during a cruise in Gulf of Mexico. It is determined that, as a function of wind speed, active whitecap fraction has significant variability and disparity compared to previous research. This finding indicates that secondary factors should be considered for accurate whitecap parameterization. This is explored using principal component analyses and random forest, which indicate sea surface temperature, swell and wave age are important to active whitecap fraction. The precise impact of sea surface temperature is further explored using analyses of variance (ANOVA), which suggest it has a positive correlation with active whitecap fraction.
The decaying stage B foam with significant variability has been found to contribute 1.5 to 40 times more to total whitecap fraction than stage A foam. In this study, we present a novel model that describes the relationship between whitecap fraction and the evolution of whitecap area, providing a method to quantify the whitecap lifetime scale. The same data from a Gulf of Mexico cruise is processed using this method. The stage B lifetime scale shows weak positive correlation with active whitecap fraction and no correlation with sea surface temperature and wind speed
Impact of Facial Divergence on Post-Treatment Settling in Patients Retained With Clear-Overlay Retainers
No full textVertical growth patterns are well-recognized by the orthodontic community as being impactful on function, form, and subsequent treatment. The hyperdivergent phenotype is characterized by smaller masticatory muscles, lower bite forces, and thinner cortical bone compared to hypodivergent subjects. As occlusion depends on dentition, muscle function, and periodontium, facial divergence plays a role in establishing occlusion. Just as orthodontics aims to improve a patient���s occlusion, a goal of orthodontics is to retain the occlusion after debonding but to allow for the vertical movement of teeth into better intercuspation, known as settling. With the determinants of occlusion being influenced by factors affected by facial divergence, there is the possibility that different facial divergence patterns have different capacities to experience settling.
The purpose of the study is to investigate and compare the changes in areas of contact and near contact in hypodivergent and hyperdivergent patients retained with a clear overlay retainer.
This study is a retrospective cohort study with patients recruited from a single private practice. 7 hyperdivergent and 11 hypodivergent patients were identified. All patients were retained with upper and lower clear overlay retainers and a lower bonded retainer. Initial lateral cephalograms were used to categorize patients as hyperdivergent or hypodivergent. Intraoral scans from debond and first retention check appointments were compared. Changes in areas of contact (AC) and areas of contact and near contact (ACNC) were used to characterize settling.
Hyperdivergent patients had a statistically significantly higher number of AC as compared to hypodivergent patients at the time of debond (T0) but not at first retention check (T1). There was no statistical difference between AC or ACNC at T0 or T2 between the two groups. There were no statistical differences detected within each group for either AC or ACNC when doing pairwise comparisons.
Without adequate power, this study instead serves to justify the benefits of repeating this study with a larger sample size. It indicates the potential for different facial divergence patterns to respond differently with the same retention protocol which could therefore impact the settling that can be achieved
Multi-Tiered Systems of Support: Implementation Experiences of High School Principals
No full textThis study aimed to explore the Multi-Tiered Systems of Support (MTSS) implementation experiences of three high school principals and their assistant principals in one North Texas public school district. The study utilized qualitative methods and case study design to better understand the principals��� overall impression of MTSS implementation and their suggestions for improving the conditions that may have hindered the implementation of MTSS on their campuses. The findings presented in this study are the analysis of data acquired through the Self-Assessment of MTSS Implementation (SAM) survey, the principal interviews, and document analysis. The analysis was guided by implementation science as proposed by Fixsen and Blas�� (2008). This analysis of the data showed that the three high schools in the study have stalled in their MTSS implementation efforts after five years, mostly during the program installation phase, despite their best efforts. To move the high schools forward from the program installation stage to the full operation stage on the implementation science continuum, I proposed recommendations that address the three main drivers of successful implementation: leadership drivers, organization drivers, and competency drivers. By systematically addressing these drivers, the high schools in the study can progress toward full implementation of MTSS
Isla Piedra: Coastal Shoreline Change of an Ancient Human Settlement on the Gulf of Mexico
No full textAlong the Gulf of Mexico, on the northwest corner of the Yucat��n Peninsula, sits the northern coastal plain of the State of Campeche. The shoreline of this plain is impacted by coastal processes and ecological succession based on low-energy waves that transport and deposit sediment. These processes form a muddy shoreline with extensive wetlands, characterized by estuaries, mangrove forests, floodplains (ci��nagas) and islands of vegetation known as hardwood hammocks (petenes). This dynamic ecological frontier is a transition zone between marine and terrestrial environments, perpetually undergoing change. Ancient human settlements of varying levels of complexity have been documented along this shoreline, all of which were subject to dynamic coastal processes���such as the case of Isla Piedra. However, there has been limited exploration into whether these dynamics have modified the landscape of these settlements over time. This research seeks to determine if the ancient inhabitants of Isla Piedra experienced a different coastal landscape compared to today and how this influenced their adaptive behaviors. First, the relationship between coastal geomorphology and ancient human settlements is established. Then, through change detection methods, a series of remote sensing satellite images of the coastline are analyzed to identify differences indicative of landscape changes. Based on the detected alterations, this research proposes potential shoreline changes that Isla Piedra inhabitants may have experienced during its primary period of ancient occupation. This change provides a foundation for future research about site formation and adaptive strategies developed by the island���s inhabitants