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Propagation Of Subdural Signals In Neurosurgical Patients With Epileptic Spasms
No full textEpilepsy is a highly prevalent disease which shows disproportionally higher rates of diagnosis and cognitive consequence in pediatric populations. A particularly concerning seizure type seen in a variety of neurological etiologies are epileptic spasms: stereotypically brief and repetitive seizures that are often associated with poor developmental prognosis. When epileptic spasms are refractory to pharmaceutical management, surgical procedures targeting seizure-generating tissue are an option that can be curative. This project characterizes high-frequency ictal activity from patients undergoing this surgery and defines functional and anatomical networks that constrain its propagation. Onset timing of detected signals on subdural electrodes were compared to metrics of white matter pathways revealed by diffusion MRI tractography. We found that the latency of high-frequency activity onset was associated with interictal spike timing and multiple diffusion MRI measures of direct corticocortical pathways, suggesting an anatomical framework of spasm propagation. Applications of this understanding may help refine interpretation and processing of presurgical data for improved surgical outcomes
Civis Americanus Sum: Mythmaking in the Movement to Reclassify Italian Alien Enemies During the Second World War
No full textThis article analyzes the reworking of a variant of the myth of Rome, the Myth of an American Rome, by the principal reclassification movement actor, Luigi Rocco Antonini, during the Second World War. It explores the discursive origins, establishes historical context, and examines the construction and synthesis of plotlines. The significance as a political myth to mobilize the people of Italian descent in support of a singular loyalty to America and to reconcile the dilemma of fighting against Italy is evaluated. Although intended to function as a liberating force, the analysis reveals the potential was undermined by various constraints
Drosophila Melanogaster X Chromosome Recruiting Elements Employ Nuclear Architecture For Msl Localization
No full textDrosophila melanogaster males increase expression from their single X chromosome to match that of the two female X’s. This requires localization of the Male Specific Lethal (MSL) complex to X linked genes and modification of chromatin by this complex. How X chromatin is selectively identified remains unclear, but cis-acting recruiting elements are involved. Chromatin Entry Sites (CES) bind an adapter protein to recruit the MSL complex directly. A class of AT-rich satellite repeats, the 1.688X repeats, are enriched on the X and facilitate compensation of nearby genes. How these elements cooperate to identify the X is unknown Chromatin state and nuclear architecture influence gene expression and dosage compensation in many organisms. In this study we explore the role of nuclear architecture factors in recognition of the male X chromosome. Genetic interactions with mutations reducing MSL localization indicated that HP2, SAF-A, ISWI, D1, Nup153 and Cp190 participate in dosage compensation. We used a reporter for recruitment to determine that HP2 and SAF-A exert non-specific effects on reporter expression. In contrast, ISWI and D1 contribute to recruitment by the CES and Cp190 influences recruitment only at 1.688X repeats. Our findings reveal that distinct aspects of chromatin organization and nuclear architecture contribute to recruitment of dosage compensation by the CES and 1.688X repeats. We postulate that recruiting elements cooperatively mark the X by engaging multiple aspects of nuclear organization
“it’s Not What You Know But Who You Know”: The Impact Of Social Connection Preference Behaviors (scpb) On Employee Attitude, Behaviors & Intentions
No full textThe aims and objectives of this study were two-fold. First, this study developed and validated a measure of Social Connection Preference Behaviors (SCPB). Findings revealed support for the SCPB measure’s content, convergent, discriminant and criterion-related validities, second-order latent structure, and internal consistency. Second, the study explored not only the direct effects of SCPB on employees’ attitudes, behaviors and intentions, but also the underlying mechanisms through which these relationships operate. Empirical findings from two studies demonstrated that SCPB was negatively correlated with job satisfaction, affective commitment and organizational justice perceptions (i.e., distributive, procedural and interactional) while positively related to CWBs and intentions to quit. Furthermore, organizations justice perceptions were found to significantly mediate the relationship between SCPB and worker attitudes, behaviors and intentions. The theoretical and practical implications of these findings are discussed
Quasiparticle Electronic Structure And Optical Properties Of Heterogeneous Interfaces And Quantum Dots
No full textThe study of heterogeneous interfaces is of utmost importance in various fields including molecular electronics, organic electronics, catalysis, and photochemistry. It continues to be a vibrant area of research due to the increasing interest in developing new and improved technological applications. This thesis focuses on investigating the electronic structure and optical properties of heterogeneous interfaces and quantum dots, crucial components in modern electronic devices. In Chapter 3, the effect of gold electrode (Au(111)) on the electronic properties of covalent organic frameworks (COFs) is thoroughly studied, shedding light on the substrate effect of these experimentally relevant materials. This chapter unveils insights into how Au substrate influences the electronic properties of COFs, providing quantitative information on the energy level alignment and charge carrier mobilities. Chapter 4 introduces a novel computational method based on ?? approximation for studying large interfaces, presenting an efficient and versatile framework for quantitatively determining electronic properties. In Chapter 5, the electronic structure of quantum dots and their assemblies, called gels, are investigated. Insights from this work outlines the fundamental differences and potential applications in next-generation electronic devices.Overall, this thesis underscores the importance of heterogeneous interfaces and quantum dots and offers valuable insight towards the rational design of novel electronic devices with superior performance and functionality
Pnpla3-148m Is Associated With Metabolic Remodeling In The Progression Of Non-Alcoholic Fatty Liver Disease
No full textThe PNPLA3 148I\u3eM variant is associated with non-alcoholic fatty liver disease (NAFLD) and its advanced-form non-alcoholic steatohepatitis (NASH). However, the detailed mechanism underlying this association remains incompletely understood. This study aims to further explore the molecular pathogenic mechanism of PNPLA3-148M-driven NASH via an integrated metabolomic and transcriptomic analysis in a humanized PNPLA3 mouse model. Transgenic mice carrying the human PNPLA3-148I or PNPLA3-148M gene isoform were fed a NASH-inducing AMLN diet for 20 weeks. Metabolomic analyses were conducted for the liver tissue and serum samples, and the transcriptome of the liver tissue was also analyzed via RNA-seq. A total of 843 and 774 metabolites were profiled in mouse liver and serum samples, respectively. In the liver, levels of 101 metabolites were found to be significantly changed in the PNPLA3-148M group compared to the PNPLA3-148I mice (p\u3c0.05). In the serum, there were 109 metabolites found to be significantly changed between the two groups (p\u3c0.05), with most of those metabolites being free fatty acids and intermediate metabolites of the fatty acid metabolism. Enrichment analysis revealed that pathways including folate metabolism, choline metabolism, citric acid cycle, glutamate metabolism, and methionine metabolism in the liver and lipids metabolism pathways in the serum were significantly different between the two strains. In a detailed analysis, PNPLA3-148M mice possesses a significant shift in energy production from glycolysis and lipogenesis to FAO and amino acids metabolism, which may promote ketogenesis. These alterations in energy production and conversion parallel a significant remodeling of lipids distribution including accumulation of cholesterol, sphingomyelins and ceramides, as well as PUFA retention in the PC fraction. Meanwhile, the active FAO may lead to an overproduction of reactive oxygen species, increasing mitochondria stress. Lastly, we observed a significant change in choline metabolism and distribution in the PNPLA3-148M mice, leading to an impaired production of glutathione and a decreased ratio of S-Adenosylmethionine and S-adenosylhomocysteine (SAM/SAH), as well as a genome-wide hypermethylation. Our study confirmed many metabolic changes associated with the PNPLA3-148M variant among both humans and multiple models in vitro and in vivo, and observed new changes in choline metabolism and DNA hypermethylation. Our findings provide further evidence to understand the mechanism underlying which PNPLA3-148M promotes the development and progression of NAFLD
Novel Transformer Architectures For 3d Multi-Modal And Multi-Organ Medical Image Segmentation
No full textMedical image segmentation is a crucial process in medical imaging analysis, enabling precise delineation of anatomical structures and pathological regions. This dissertation explores the evolution and application of advanced deep learning models, specifically focusing on the integration of transformers and convolutional neural networks (CNNs) for enhanced medical image segmentation. The primary goal is to improve segmentation accuracy and efficiency in clinical settings, particularly for CT and MRI images.
The dissertation is structured around three key innovations. First, we introduce FocalUNETR, a novel transformer-based architecture designed to address the limitations of traditional CNNs in capturing long-range dependencies and global context in 2D CT-based prostate segmentation. FocalUNETR employs focal self-attention mechanisms and incorporates an auxiliary boundary-aware regression task to enhance segmentation precision, particularly in cases with unclear boundaries. Second, we present SwinAttUNet, a hybrid architecture combining CNNs and Swin Transformers for automatic 3D multi-organ segmentation on CT images. This approach leverages the local feature recognition capabilities of CNNs and the global contextual understanding of transformers. Third, we develop MulModSeg, a multi-modal segmentation strategy aimed at improving the segmentation of unpaired CT and MRI images. MulModSeg enhances feature extraction and model robustness by incorporating modality-conditioned text embedding and an alternating training procedure.
Extensive experiments on private and public datasets validate the effectiveness of these proposed methods. FocalUNETR achieves superior performance in 2D prostate segmentation, while SwinAttUNet outperforms state-of-the-art 3D segmentation models in both quantitative and qualitative evaluations. MulModSeg shows marked improvements in multi-modal segmentation tasks, highlighting its potential for clinical applications. This dissertation provides comprehensive frameworks for developing more accurate, efficient, and robust segmentation models, paving the way for future advancements in medical imaging and diagnostics
Density Functional Studies Of Molecular Separation And Charge Transport
No full textThis thesis presents a series of studies which can be grouped majorly into two sections both focusing on the utilization of density functional theory techniques; Molecular electronics and Molecular separation. Molecular electronics has been anticipated to hold a great future as it seeks to apply molecular building blocks in the creation of electronic components. On the other hand, the utilization of mild conditions in chemical processes is geared toward the major goals of green chemistry as it produces less waste and is cost-effective. Thus, this dissertation tackles and answers some of the unanswered questions in literature by using theoretical methods (my part) and experimental means via collaborations.In the field of molecular separations, we illustrated the binding mechanism of small hydrocarbons in metal-organic frameworks (MOFs) without open metal sites. Our findings encourage the future designs of these type of MOFs as the presence of small functional groups within the pore are promising and can serve as open-metal sites to enhance separation selectivity of small hydrocarbons and other unsaturated compounds. Also in the field of molecular separations, we highlight the importance of Rare-earth elements (REEs), its challenges and why it is necessary we focus finding other ways for their separations. Using binding energy studies, we propose a model and our findings which encourage the use of ligand-associated sorbent media for the enhanced performance of ligand-REE binding and separations even at low pH and for the separation of scandium from the remaining REEs. In our study, we utilized a modified DTPA as our ligand which has already been studies experimentally for REE extraction on a substrate. In the field of molecular charge transport, we showed two things in two different projects and is as follows: (1) we conclude that highly polarized molecular bridge motifs are poor choices for the construction of ordered polymers with high in-plane conductivity. (2) A robust binding is achieved when wax–coated Au tip and secondary amines forms a junction and that was associated with the more frequent formation of Au adatoms. Our theoretical calculations confirmed that Au adatom has a highest binding energy upon trying several models of Au binding motif