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Unfitted Finite Element Methods for Shape Optimization and Liquid Crystals
Get PDFWe present an approach to shape optimization problems that uses an unfitted finite element method (FEM). The domain geometry is represented, and optimized, using a (dis- crete) level set function and we consider objective functionals that are defined over bulk domains. For a discrete objective functional, defined in the unfitted FEM framework, we show that the exact discrete shape derivative essentially matches the shape derivative at the continuous level. In other words, our approach has the benefits of both optimize-then- discretize and discretize-then-optimize approaches.
Specifically, we establish the shape Fréchet differentiability of discrete (unfitted) bulk shape functionals using both the perturbation of the identity approach and direct perturbation of the level set representation. The latter approach is especially convenient for optimizing with respect to level set functions. Moreover, our Fréchet differentiability results hold for any polynomial degree used for the discrete level set representation of the domain. We illustrate our results with some numerical accuracy tests, a simple model (ge- ometric) problem with known exact solution, as well as shape optimization of structural designs.
We also present some analysis of the Landau–de Gennes model for liquid crystals in an unfitted framework and derive a consistency estimate for a scalar-valued version of this PDE. These results will (eventually) form the foundation of an unfitted method for the Landau–de Gennes model
NEURONAL CFTR: A STUDY OF SUBCELLULAR LOCALIZATION AND INTERACTIONS WITH IMPLICATIONS FOR A ROLE IN SYNAPTIC TRANSMISSION
Get PDFProtein-protein interactions vary among cell types and the localization of these interactions help to define protein function. The function of cystic fibrosis transmembrane conductance regulator (CFTR) is well established in the context of epithelial tissue due to the debilitating effects of its mutations that cause the disease cystic fibrosis. While in neurons a role has been established in our lab for CFTR in the regulation of cytosolic Cl- in retinal amacrine cells (ACs). This research sets out to learn if CFTR has a synaptic role. Exploring this potential role, localization of CFTR was examined using fluorescent and immunogold labeled transmission electron microscopy to achieve subcellular resolution of CFTR throughout the adult chicken. CFTR was found in areas of the retina that include the ellipsoidal mitochondria, and multiple locations of the inner retina including conventional and ribbon synapses. A role in synaptic transmission was tested by recording spontaneous postsynaptic quantal currents that were found to increase in frequency upon pharmacological inhibition of CFTR. This elevation in frequency points to a presynaptic role. Interestingly, in epithelia there is an established functional interaction between CFTR and the SNARE protein Syntaxin 1A. This interaction was verified in the retina and brain by a CFTR baited co-immunoprecipitation of Syntaxin 1A and fellow SNARE SNAP25. Further verification by an in vitro binding assay showed a more than 2-fold increase of STX1A and SNAP25 when the co-immunoprecipitation was supplemented with purified CFTR protein. The localization of this interaction in ACs was explored using fluorescent microscopy and proximity ligation assay showing a strong co-localization between CFTR and STX1A in the processes of retinal ACs where synapses occur. To broaden our understanding of observed protein interactions with CFTR, eluate from a bait CFTR co-immunoprecipitation was analyzed via mass spectrometry. Our analysis found 621 CFTR interactors in brain tissue. Following data filtering, 89 proteins were found to be a synaptic protein using the databases Gene Ontology, UniProtKB, and with literature searches. Overall, the broad scope of proteins identified in our analysis suggest that CFTR has multiple functions in the nervous system
Leading the Charge: Chief Diversity Officers Overcoming Barriers and Shaping Diversity Leadership in the U.S.
No full textThis dissertation examines the multifaceted challenges confronted by Chief Diversity Officers (CDOs) within Corporate America and delineates the strategies they deploy to navigate these obstacles. Through qualitative interviews and analysis of corporate policies across diverse sectors, this study identifies key barriers to implementing effective diversity, equity, and inclusion (DEI) initiatives, including resistance to change, limited resources, and organizational culture. It further explores innovative strategies CDOs employ to foster inclusive environments and drive systemic change. The findings contribute to a deeper understanding of the CDO role and offer practical insights for enhancing DEI effectiveness in corporate settings
IMPACT OF GLUFOSINATE ON SUGARCANE YIELD AND YIELD COMPONENTS WHEN APPLIED POST-DIRECTED AND ITS EFFICACY IN CONTROLLING EMERGED ITCHGRASS (ROTTBOELLIA COCHINCHINENSIS)
Get PDFWeed control is extremely important in the Louisiana sugarcane (Saccharum spp.) industry, as it is a perennial crop that grows back after each harvest. Fields are kept weed free using mechanical and chemical methods to prevent weed-crop competition and further establishment of weed populations. The weed itchgrass (Rottboellia cochinchinensis) has become problematic for Louisiana sugarcane producers. Sometimes, itchgrass can still emerge after farmers have made a pre-emergence (PRE) herbicide application. These weeds are usually controlled using the herbicide paraquat dichloride (paraquat) in post-emergence (POST) directed applications. In recent year, 2016-2024, the United States Environmental Protection Agency has placed restrictions on paraquat usage due to health concerns. Another herbicide that has been used in these applications successfully in other sugarcane producing countries is glufosinate-ammonium (glufosinate). Glufosinate applications were evaluated in Louisiana in 2023 and 2024. The objectives of this study were to 1: determine the tolerance of the Louisiana sugarcane variety ‘L 01-299’ to a post-directed application of glufosinate and 2: to evaluate the efficacy of glufosinate in controlling itchgrass. Five field trials were conducted across three locations in Louisiana in 2023 and 2024 comparing five herbicide treatments, three glufosinate treatments, a metribuzin and triclopyr treatment, a paraquat treatment, and an untreated control, to test for sugarcane tolerance. Among all treatments, sugarcane yield, sucrose content and sugar yield were found to be statistically similar. To test for efficacy in controlling itchgrass, two trials were conducted in St. Martinville, Louisiana in 2024 comparing the same treatments on three different sizes of itchgrass. Across all sizes, glufosinate applications provided the highest mean control at three weeks after treatment. Based on these results, glufosinate is a safe and effective option to be used in POST-directed applications in sugarcane if labeled for use in the United States
Global Ocean Bottom Temperature Observation Design: Observing System Simulation Experiments For Strategic Deployment of SMART Subsea Cables
No full textDeep-ocean observations below 2000 meters remain limited, restricting our ability to model global ocean processes critical to climate prediction. This thesis evaluates the potential of SMART (Science Monitoring and Reliable Telecommunications) subsea cables to address these observational gaps by conducting Observing System Simulation Experiments (OSSEs) and adjoint sensitivity analyses using the MITgcm ocean model and ECCO outputs.
Vertical decorrelation analysis showed that temperature and salinity in key regions decouple from the upper ocean beyond 2000 m. Over 60% of the proposed SMART cable sites exhibited decorrelation depths exceeding Argo’s maximum sampling depth, highlighting their strategic value for deployment.
A comparison of the high-resolution ECCO LLC4320 simulation with the coarser LLC270 estimate demonstrates the importance of grid spacing. Globally, the standard deviation of bottom temperature rises from 0.071°C in LLC270 to 0.101°C in the daily LLC4320 fields (42%), while salinity variability increases from 0.0125 PSU to 0.017 PSU (36%). These larger fluctuations reflect the ability of the 1–2 km mesh to resolve mesoscale and submesoscale structures that are smoothed out on the 25 km grid.
Adjoint sensitivity experiments identified high-latitude regions, including the Arctic and Portugal-Azores corridor, as particularly responsive to bottom temperature perturbations, affecting sea surface height and barotropic velocities. However persistent numerical instabilities in salinity and SSH fields, especially in the Beaufort Gyre, suggest a need for improved parameter tuning.
Overall, this work provides a quantitative framework for optimizing SMART subsea cable placement. By targeting underobserved, high-sensitivity regions, these systems can improve global ocean monitoring, strengthen climate models, constrain deep-ocean processes, and support climate resilience
THE ROLE OF MENTAL HEALTH LITERACY AND SOCIAL MEDIA IN SHAPING UNIVERSITY STUDENTS’ INTENTIONS TO USE TELEHEALTH SERVICES: A THEORY OF PLANNED BEHAVIOR APPROACH IN A POST-PANDEMIC SOCIETY
Get PDFThis study examined the relationships between mental health literacy and social media use as an informational resource in college students and their intentions to use teletherapy. Using the theory of planned behavior as the framework, this research explores how attitudes towards teletherapy, subjective norms, and perceived behavioral control influence students\u27 willingness to seek out mental health services such as teletherapy. Findings revealed that mental health literacy is a strong predictor of students\u27 attitudes and perceived behavioral control, reinforcing prior research that links literacy to better health management among patients. Social media was also a strong predictor of subjective norms, highlighting the influence social communities have on students\u27 perceptions of teletherapy. However, while social media contributed to positive attitudes among students, its predictive power on perceived behavioral control was limited.
Through the identification of key factors influencing college students\u27 intentions to use teletherapy services, this research contributes to the growing conversation surrounding digital mental health services after COVID-19. These findings provide valuable ideologies for universities and mental health practitioners who are seeking to implement programs or campaigns targeting college students\u27 mental health management. This research showcases the importance of mental health literacy and providing supportive communities on social media channels to continue fostering positive well-being among students
Is Verbal Rehearsal Strategic? An Investigation into Overt Rehearsal of Nameable Pictures in 5- to 10-Year-Old Children
Get PDFThough verbal rehearsal is a frequently endorsed strategy for remembering short lists among adults, there is ambiguity around when children deploy it, and what circumstantial factors encourage them to rehearse. We recoded data from a recent multilab replication of a serial picture memory task in which children were observed for evidence of task-related speech or lip movements to extract finer-grained detail about how children spoke during the task. With these data, we aimed to better understand the manner in which children rehearse and the task scenarios which elicit overt rehearsal. Children in several countries from 5 to 10 years old were tasked with remembering 2–5 nameable pictures in serial order across a 15-second delay. Coders categorized children’s speech or lip movements as reflecting fixed rehearsal of the last-presented item only, cumulative rehearsal of all the items presented so far, or some attempt at cumulative rehearsal. We found that most children, regardless of age, did not overtly rehearse at all during presentation of the objects or during the delay period. However, children who sometimes overtly rehearsed recalled longer lists of items than children who did not. Though rare, cumulative rehearsal was most frequently observed for list lengths close to the participant’s demonstrated maximum recall length. Critically, on the trials where overt rehearsal was observed, recall improved. This evidence supports previous suggestions that rehearsal strategy, and possibly also its effectiveness, changes with task difficulty, and raises further questions about how verbal rehearsal affects serial recall
Evaluating Crop Response from Quizalofop and Fluridone Application in Louisiana Rice (Oryza sativa L.)
Get PDFA field study was conducted at the H. Rouse Caffey Rice Research Station (RRS) in 2023 and 2024 to evaluate crop safety when quizalofop applications were made on ‘PVL03’ before and after overcast growing conditions. Factor A (main plot) consisted of no shade, shade for a period of 7 days prior to quizalofop application, or shade for a period of 7 days after quizalofop application. Factor B (sub plot) consisted of shade coverage representing simulated overcast weather at 0, 30, 60, or 90%. Factor C (sub-sub plot) consisted of no quizalofop, quizalofop at 120 g ha-1, or quizalofop at 240 g ha-1. In general, rice injury was observed when simulated overcast weather was present before and after quizalofop applications. Additionally, the results of this study suggest that crop response is light dependent and higher injury can be expected when overcast growing conditions are present after a 120 g ha-1 application of quizalofop.
A field study was conducted at the RRS in 2024 to evaluate crop safety of fluridone applications on five rice lines. The rice varieties evaluated consisted of ‘PVL03’, Jupiter, and Avant and the hybrids evaluated consisted of ‘RT7321’ and ‘RT7523’. Factor A consisted of rates of fluridone at 0, 84, 126, and 168 g ha-1. Factor B consisted of five application timings targeting preemergence (PRE), delayed preemergence (DPRE), 1-2 leaf rice, 3-4 leaf rice, and preflood. Fluridone applications made at PRE resulted in the highest frequency of rice injury and yield loss across all rice lines evaluated. Similarly, applications of 168 g ha-1 of fluridone resulted in the highest frequency of injury at each application timing and should be avoided. DPRE applications across all flooded rice trials showed that lower rates caused less yield loss. Fluridone applied on 1-2 and 3-4 leaf rice resulted in greater yields than PRE and DPRE applications of fluridone. Preflood applications were the safest applications across flooded and furrow-irrigated rice resulting in minimal yield loss in comparison to the check
Personal Life
No full textThis novel in progress follows a woman named Sheila Dodge.
Sheila is a private person. She can’t orgasm when she has sex with her boyfriend, Derek. The only time she can orgasm is when she watches the sex tape of Alexandra Anders, the star of her favorite show, Hollywood Housewives. She’s in love with her best friend, Kate, but she can’t find the words to express it to her. She has feelings, but she can only express them via the reality television shows she watches.
As Sheila and Derek have sex in an attempt to save their relationship, Sheila starts to hear an animal under the house just when she’s about to come. With Kate’s help, she digs up her house but finds nothing there. The only other person who can hear the animal is Emmett Wiler, an old friend of Kate’s and a mysteriously disgraced Hollywood filmmaker. Sheila pursues a film project with Emmett to get the animal on tape, straining her relationships with Derek and Kate. Intimately subject to Emmett\u27s idiosyncratic artistic demands, and more alone than ever, Sheila must expose her private parts—physically and mentally—in order to prove her perspective
Functional and Comparative Genomics of the C.sojina- Soybean Interaction
No full textFrogeye leaf spot (FLS), caused by Cercospora sojina, is a significant foliar disease of soybean (Glycine max) and is responsible for substantial yield losses worldwide. While management strategies rely on host resistance and fungicide applications, the emergence of new virulent races and fungicide-resistant isolates necessitates a deeper understanding of C. sojina host interactions and genomic variability. Here, we employed comparative and functional genomic approaches to decipher the molecular mechanisms underlying the C. sojina-soybean interaction. A dual RNA sequencing approach was used to identify transcriptomic changes in G. max cultivars Blackhawk (susceptible) and Davis (resistant) across multiple infection stages (3, 9, and 14 days post-inoculation). Differential expression analyses and principal component analysis (PCA) revealed dynamic transcriptional changes associated with susceptibility and resistance. Davis exhibited an early activation of defense responses linked to its resistance to C. sojina, involving salicylic acid signaling (SA), naringenin production, and brassinosteroid regulation. On the other hand, Blackhawk showed a delayed immune response coinciding with the pathogen’s transition to necrotrophy. Infection stage-specific fungal effector gene expression was also characterized, which identified 16 effectors with distinct temporal expression patterns. To complement our transcriptomic findings, we performed a comparative genomics analysis of four C. sojina isolates: TN81 and TN209 from the United States, Race11 from Argentina, and Race15 from China, to focus on pangenome variation, virulence, and genome plasticity. The study uncovered substantial genome plasticity characterized by large-scale chromosomal rearrangements and transposable element expansions (24.52%-26.95% of the genome). Whole genome alignments identified eight major translocations in TN209, enriched in transposable elements, indicating their crucial role in genome evolution. Pangenome analysis classified 10,741 core genes, with effector orthogroups being enriched in accessory and singleton genes. In conclusion, this study explores host resistance mechanisms and pathogen adaptability to enhance potential molecular targets for breeding disease-resistant soybean varieties and improving C. sojina management strategies