SkullGAN: Synthetic Skull CT Generation with Generative Adversarial Networks

Deep learning offers potential for various healthcare applications involving the human skull but requires extensive datasets of curated medical images. To overcome this challenge, we propose SkullGAN, a generative adversarial network (GAN), to create large datasets of synthetic skull CT slices, reducing reliance on real images and accelerating the integration of machine learning into healthcare. In our method, CT slices of 38 subjects were fed to SkullGAN, a neural network comprising over 200 million parameters. The synthetic skull images generated were evaluated based on three quantitative radiological features: skull density ratio (SDR), mean thickness, and mean intensity. They were further analyzed using t-distributed stochastic neighbor embedding (t-SNE) and by applying the SkullGAN discriminator as a classifier. The results showed that SkullGAN-generated images demonstrated similar key quantitative radiological features to real skulls. Further definitive analysis was undertaken by applying the discriminator of SkullGAN, where the SkullGAN discriminator classified 56.5% of a test set of real skull images and 55.9% of the SkullGAN-generated images as reals (the theoretical optimum being 50%), demonstrating that the SkullGAN-generated skull set is indistinguishable from the real skull set - within the limits of our nonlinear classifier. Therefore, SkullGAN makes it possible to generate large numbers of synthetic skull CT segments, necessary for training neural networks for medical applications involving the human skull. This mitigates challenges associated with preparing large, high-quality training datasets, such as access, capital, time, and the need for domain expertise.Comment: The first two authors contributed equall

Histamine modulates spinal motoneurons and locomotor circuits

Spinal motoneurons and locomotor networks are regulated by monoamines, among which, the contribution of histamine has yet to be fully addressed. The present study investigates histaminergic regulation of spinal activity, combining intra- and extracellular electrophysiological recordings from neonatal rat spinal cord in vitro preparations. Histamine dose-dependently and reversibly generated motoneuron depolarization and action potential firing. Histamine (20μM) halved the area of dorsal root reflexes and always depolarized motoneurons. The majority of cells showed a transitory repolarization, while 37% showed a sustained depolarization maintained with intense firing. Extracellularly, histamine depolarized ventral roots (VRs), regardless of blockage of ionotropic glutamate receptors. Initial, transient glutamate-mediated bursting was synchronous among VRs, with some bouts of locomotor activity in a subgroup of preparations. After washout, the amplitude of spontaneous tonic discharges increased. No desensitization or tachyphylaxis appeared after long perfusion or serial applications of histamine. On the other hand, histamine induced single motoneuron and VR depolarization, even in the presence of tetrodotoxin (TTX). During chemically induced fictive locomotion (FL), histamine depolarized VRs. Histamine dose-dependently increased rhythm periodicity and reduced cycle amplitude until near suppression. This study demonstrates that histamine induces direct motoneuron membrane depolarization and modulation of locomotor output, indicating new potential targets for locomotor neurorehabilitation

A Statistical Approach Towards Understanding the Contribution of Molecular Weight to Amino Acid Distribution in PDZ Protein Domain

Understanding the factors that govern protein folding and function is of necessary importance in protein design. At the core of this folding regime, position-specific amino acid distribution determines the propensities of the sequence towards particular secondary and tertiary structures. Several attempts have been made in understanding the key contributors that influence or at times dictate this position-specific distribution. To further elucidate these contributors, we have investigated the role of molecular weight in fixed configuration of the PDZ protein domain in position pairs that are within a certain spacial limit of one another. Furthermore, molecular weight-based site-specific distribution of amino acids in one of these pairs of meaningfully correlated positions fits a modified Boltzmann distribution. This tells us that for position pairs that are affected by molecular weight, under certain criteria, predictive models could be developed

Correlating Reactive Oxygen Species Release and Regenerative Neuritic Outgrowth of an Identified Neuron in the Pond Snail, Lymnaea stagnalis.

Model organisms such as Lymnaea stagnalis are often helpful in studying microscopic physiological phenomena such as neural regeneration. Here, we investigated the relationship between release of reactive oxygen species (ROS) by neurons and glial cells following crushing of a peripheral nerve trunk and regenerative outgrowth of the interneuron LPeD1. ROS emitted from crush sites, visualized using specific fluorescent probes, was positively correlated with neuronal sprouting of LPeD1 identified using iontophoretically labelled axons via live-cell imagin

Maternal Employment and Family Socioeconomic Status Effects on Daughter's Self-Concept and Attitude Towards Women and Work: LISREL Models

158 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1988.The purpose of this study was to investigate the effect of mother's employment variables and family socioeconomic status on daughter's self-concept and attitude towards women and work. Two groupings of 9th and 12th grade subjects were investigated: daughters whose mothers were employed at least part of the time during the daughter's life (group 1, n = 512); and the group 1 sample plus daughters whose mothers had never been employed (group 2, n = 690).The LISREL VI (Linear Structural Relationships) program was used to obtain a satisfactory causal model in which the independent variables were Mother's Occupational Status, Mother's Education, and Family Socioeconomic Status (SES); the dependent variables were Daughter's Academic, Family, General, and Social Self-esteen, Independent Self-concept, Attitude Towards Women and Work, and total amount of time mother has worked outside the home in years (Total Work). Results for both groups indicate that Total Work had a significant direct effect on daughter's Attitude Towards Women and Work. There was also a moderate but significant direct effect of Total Work on daughter's Independent Self-concept and on Social Self-esteem for both groups. Only when daughters with housewife mothers (group 2) were included in the sample did the effect of the SES variable become significant. The pattern of causal paths among the self-concept variables and Attitude Towards Women and Work was almost the same for both groups, but for group 1 the relationships were stronger. This indicates that the causal relationships among the dependent variables exist apart from the effect of the independent variables.These findings have implications for young women, especially their early socialization by parents and educators. Parents, especially the mothers, should be aware of the potential positive impact of their employment on their daughter's occupational sex-role concept and on their independence. Not only parents but also teachers, counselors, and educational policy makers could encourage positive attitudes toward work on the part of young women by introducing them to the important role of women in work and family roles, presenting them with mothers who have satisfactorily combined these roles and providing them with educational opportunities based on their individual academic potential and interest.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD