Mason Journals (George Mason Univ.)
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Julián Casanova, A Short History of the Spanish Civil War and Giles Tremlett, The International Brigades: Fascism, Freedom and the Spanish Civil War
No full textThe Hoplite Hypocrisy: Teaching Ancient Greek Warfare in an American Classroom
Get PDFIn the field of Ancient Greek history, war and politics are often presented as two sides of a single coin. In the nineteenth and twentieth centuries, scholars argued that the emergence of heavily armored warriors, or hoplites, inspired some of Europe’s earliest democracies. This narrative was especially attractive to American philhellenes and other organizations that sought to elevate Ancient Greece as the root of “Western Civilization,” but it ultimately has little to no basis in our archaeological and historical evidence. Nevertheless, the hoplite orthodoxy found real traction among right-leaning political movements, and a small vocal minority within the academy have entrenched themselves in favor of this paradigm. This article presents the hoplite orthodoxy, its detractors in the academy, and its broader impact outside the field. The complexities of this controversial paradigm leave world historians in an awkward situation, and silence only creates space for the continued misappropriation and misinterpretation of the past. In what follows, I advocate for highlighting the role of enslaved people in Ancient Greek warfare as a pedagogical device. By exploiting the rift between our primary sources and the modern-media fantasy, we can help our students confront the hoplite hypocrisy head-on
Evaluating Self-Determination and Academic Enabling Behaviors in Students with Intellectual Disabilities in Inclusive Postsecondary Education Programs
No full textInclusive postsecondary education (IPSE) programs provide students with intellectual disabilities (ID) an opportunity to access higher education. As these programs have grown over the decades since their inception in 2010, it is becoming increasingly important that these programs use data-driven interventions to improve student outcomes, both academically and non-academically. Research in the area of non-cognitive skills suggest that focusing students with ID on skills like motivation and engagement or attitudes like action control beliefs can improve their performance in IPSE programs and lead to positive academic and career outcomes in the future. Here, we performed correlation analysis and multiple regression on two non-cognitive skills assessments, the ACES Academic Enablers and Self Determination Inventory, collected from ISPE students. This analysis shows that the degree of a student’s action-control beliefs as measured by the SDI is predictive of their ACES Academic Enablers performance. This suggests that interventions targeting the concept of action control beliefs can improve practical non-cognitive skills that can lead to academic and professional success for students with ID
Using Immunohistology to Investigate Cholinergic Fiber Density across Layers in the Medial Entorhinal Cortex
No full textAcetylcholine is a neuromodulator that plays a key role in spatial navigation, learning and memory by modulating neurons in the hippocampus and medial entorhinal cortex (MEC). Acetylcholine released in the MEC is produced by cholinergic projection neurons located in the medial septum and diagonal band of Broca (MS). Acetylcholine is released at synaptic terminals in the MEC and via volume transmission to modulate activity of neurons at the individual and population level. Yet, the exact density of cholinergic projection fibers in different layers of the MEC has not been quantified. To address this question, we used a ChAT-Cre mouse and stereotaxic virus injection to transfect the cholinergic neurons in the MS with a conditional recombinant adeno- associated virus (AAV) coding for the green fluorescent protein (GFP). The GFP was only expressed in the cholinergic cells. After 14 days, we euthanized the mouse and performed a transcardiac perfusion procedure to preserve the brain in formalin. Then, we sliced the MS (coronally) and the MEC (sagittally). We processed the brain slices using immunohistology with anti-GFP antibodies. Following the staining, we imaged the brain slices using confocal microscopy and measured the fluorescence intensity in each of the six layers. The rationale for this approach was that layers with the highest fluorescence likely have the highest amount of cholinergic innervation. The results of this study will help us identify which neuron types and compartments in the MEC are preferentially targeted by acetylcholine. This is particularly interesting in the context of grid cells, a type of neurons in the MEC which fire in a grid-like pattern when an animal is navigating its space, providing a neuronal base for memory-guided spatial navigation
Investigating the correlation between cholinergic neuron activity and real-time behavior in mice using machine learning techniques
No full textCholinergic modulation, regulated by the neurotransmitter acetylcholine, is critical for cognitive functions and behaviors associated with spatial memory and navigation. The activity of cholinergic projection neurons is correlated with changes in cognitive function, brain state, and behavior. However, there is limited research investigating the real-time activity of cholinergic neurons in relation to behavior. In our study, we aim to explore this relationship by recording cholinergic activity in mice during an object location memory task, specifically focusing on the mice's ability to recall the location of objects within a given environment. To measure activity of cholinergic neurons, we utilize fiber photometry, a technique that employs fiber optics to transmit and receive light signals. A Cre-dependent recombinant adeno-associated virus (rAAV) coding for GCaMP is injected into the medial septum of ChAT-Cre mice, creating fluorescence when the neurons generate action potentials. The object location memory task consists of a probe and test phase. During the probe phase, the mice explore an environment with two identical objects for a fixed duration of 15 minutes. After a 1-hour delay, one of the objects is relocated to a novel position near the opposite corner, and mice explore both objects for 15 minutes (test phase). Video tracking is employed throughout both phases to capture the mice's movements and behavior. Video-tracked pose and behavior was analyzed using deep learning applications, including DeepLabCut and DeepEthogram. DeepLabCut is utilized for precise markerless tracking of the mice's body positions and calculating speed. DeepEthogram applies machine learning algorithms to classify behavioral activities such as walking, grooming, and rearing. Our research approach provides valuable insights into the cholinergic modulation of cognitive processes underpinning spatial learning with potential implications for understanding neurological diseases
Effects of an invasive barnacle parasite and salinity stress on the functional response of the native mud crab Rhithropanopeus harrisii
No full textLoxothylacus panopaei, an invasive parasitic barnacle, invaded the Chesapeake Bay from the U.S. Gulf Coast in the 1960s. It infects nine species of mud crabs, including the white-fingered mud crab Rhithropanopeus harrisii, an important prey item and predator in estuarine communities. Previous work shows that L. panopaei forms an internal network of rootlike rhizoids in its host, castrating them, and may alter infected crabs’ eating patterns, which can have negative effects on native wildlife populations. Both parasite and host also have specific salinity tolerance ranges, where lower salinities are stressful. To test how salinity stress affects the feeding behavior of R. harrisii crabs when infected with L. panopaei, 20 infected and 20 uninfected crabs were acclimated to five levels of salinity (2, 4, 6, 10, and 12 ppt) at five levels of prey density (5, 10, 15, 20, and 50 chironomid insect larvae) and assessed feeding after four hours. Prey consumed was then compared between infected and uninfected crabs to observe whether salinity interacted with infection. Preliminary trials show that at the highest prey density, R. harrisii ate more at higher salinities (70% consumed at 10 ppt and 76% at 12 ppt) than at low salinities (44% at 2 ppt). Infected crabs ate fewer prey than uninfected crabs only at low salinities; there was little difference in feeding between uninfected and infected R. harrisii at higher salinities. These results suggest that low salinity stress interacts with infection status to impact R. harrisii feeding habits
AI-Powered ETFs: A Quantitative Analysis of Performance, Risk, and Volatility in Financial Markets
No full textThe rise of artificial intelligence (AI) in financial markets has prompted a significant shift in investment strategies, particularly in the management of Exchange-Traded Funds (ETFs). This study investigates the performance of ETFs utilizing AI-assisted strategies compared to traditional ETF management approaches. By hand-collecting a list of ETFs that employ AI algorithms in their investment strategies, we assess the return on investment, risk-adjusted returns, and volatility of these ETFs. The findings suggest that AI-assisted ETFs tend to outperform traditional ETFs in terms of higher Sharpe ratios and reduced portfolio volatility, highlighting the potential of AI integration in enhancing ETF performance. The effects are more pronounced in recent years, coinciding with significant advancements in AI. This paper contributes to the emerging field of AI in finance by demonstrating the tangible benefits of AI algorithms in real-world investment scenarios and setting a benchmark for future innovations in ETF management. The implications of this research are significant, suggesting potential trends toward more AI-integrated financial strategies in managing diversified investment portfolios