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Item Open Access Reconfigurable Beamforming for Automotive Radar Sensing and Communication: A Deep Reinforcement Learning Approach(2024-07-19)In this article, we present a novel low-cost, dual-function radar-communication system that addresses dynamic environments such as those arising in automotive applications. The low cost is achieved by using a sparse phased arrays equipped with quantized double-phase shifters. The operation in dynamic environments is achieved via a deep reinforcement learning (DRL) approach that adaptively selects a small subset of transmit antennas and adjusts the phase shifters such that the transmitted energy is concentrated on the communication user and the target of interest, while the interference to other radars is reduced. The action space in the DRL approach increases fast with the number of antennas and the number of bits used in quantization, and as a result the complexity of the design problem grows exponentially. To tackle the resulting curse of dimensionality in the action space, we adopt the Wolpertinger strategy, which incorporates the nearest neighborhood component to project the vast action space into a smaller, more manageable space while maintaining the desired performance. Numerical results demonstrate the feasibility of our proposed method.Item Open Access The Operation Diversify Plastic Surgery Experience: Pioneering Diversity, Equity, and Inclusion Initiatives(2024-04-01)Background: In 2020, African Americans represented only 1.4% of plastic surgeons despite comprising 12.4% of the US population, with Latinos making up 3.6% of plastic surgeons while comprising 18.5% of the US population. These disparities, like other surgical specialties, exacerbate existing health inequalities. From insufficient patient care to lack of research on minorities, plastic surgeons are expected to treat a population they know little about. To address this diversity gap, students from Howard, Meharry, and Morehouse, three historically black colleges and universities (HBCUs), initiated Operation Diversify Plastics (ODP). ODP’s goal is to increase mentorship, sponsorship, and provide diverse students with plastic surgery experience. This study aimed to identify strengths and needs among ODP participants interested in PRS Methods: An anonymous survey was administered to participants both before and after ODP speaker sessions examine students’ engagement with the field of plastic surgery. We assessed students’ confidence levels in various aspects, including their knowledge of the PRS residency application process, their ability to secure letters of recommendation (LORs), and their proficiency in constructing a personal statement. We sought to understand students’ expectations and aspirations related to attending these speaker sessions. Qualitative data was collected to gather insights into the aspects of future sessions that students find valuable and wish to be included. Results: Forty students participated, 90% of which self-identified as underrepresented in medicine (URiMs) and 46% without a home PRS program. The majority of ODP participants were interested in increasing opportunities for mentorship (47%), knowledge of PRS applications (22%), research fellowships (17%), and PRS knowledge (14%). Personal statement drafting, obtaining letters of recommendation, and knowledge of PRS application process were self-identified weaknesses of ODP participants rated at a median 2/5 on the likert scale (IQR-1-4). Confidence in a competitive CV and networking abilities were areas of strength (p<0.05). ODP participants increased exposure to PRS by attending virtual program meet and greets (42%), contacting neighboring PRS programs faculty, and attending conferences (58%). Students desired more representation of residents and academic surgeons from underrepresented racial/ethnic backgrounds and workshops focused on the application process and interviewing skills. Conclusion: URiM students pursuing PRS have distinct needs, with a strong emphasis on acquiring knowledge about PRS, understanding application process intricacies, and exploring opportunities for research. These findings underscore the crucial role of mentorship within the field of surgery, emphasizing the necessity for guidance and support from peers, residents, and established PRS surgeons as an essential cornerstone for achieving success in this specialized field.Item Open Access Curated phytochemicals of Annona muricata modulate proteins linked to type II diabetes mellitus: Molecular docking studies, ADMET and DFT calculation(2024-04-26)One of the medicinal herbs utilized in treating diabetes traditionally is Annona muricata. This work investigates the effect of phytochemicals from A. muricata on the therapeutically important protein targets associated with type II diabetes mellitus (T2DM) using a computational approach. Compounds (Phytochemicals) previously identified in A. muricata were docked against proteins of interest to find therapeutic hit compounds. The stability of the ligand-protein complexes was examined after selecting proteins that bind well with the discovered hits, and ADMET properties of the ligands were also predicted to determine their toxicity and drug-likeness. In addition to studying the compounds' softness, hardness, electron affinity, and electrostatic potential, the Schrödinger material science Jaguar fast engine was used to study their frontier molecular orbital (FMO). The targets aldose reductase (ALR), 11beta-hydroxysteroid dehydrogenase type 1 (11-HSD1), and diacylglycerol O-acyltransferase 1 (DGAT1) exhibited the highest binding affinities from the early screening of compounds against fifteen (15) proteins linked with T2DM. While eight (8) phenolic compounds of the plants had comparatively high docking scores with 11β-HSD1 and ALR, seven (7) acetogenins had good binding affinities with DGAT1. These top-scoring compounds exhibited considerable ADMET profiles. Additionally, the phenolic compounds that are considered as hits adhered to the Lipinski rule of 5 and can be thought of as potential drug candidates. Genistein and kaempferol are the most reactive ligands in terms of quantum mechanics. The information from this study could be used to create an alternative anti-diabetic drug with better efficacy.Item Open Access Carbonic anhydrase inhibitors improves cognitive functions in Tg2576 AD mice(2025-01-03)Background Over the years, Alzheimer’s Disease (AD) has been identified as a multifactorial disease, with cerebral vascular dysfunction being one of the most common and early pathological features. Vascular risk factors (VRF) are thought to further increase AD risk and pathology. Cerebral Amyloid Angiopathy (CAA) is defined as the accumulation of amyloid-beta (Aβ) on the vascular wall. CAA occurs progressively with age in human AD brains, vascular dementias, and the Tg2576 AD mouse model. The Tg2576 develops significant amounts of parenchymal Aβ plaques and vascular amyloid deposits making it a valuable model to study CAA and AD. To study the contribution of VRF to CAA and AD pathology, we induced hyperhomocysteinemia (HHcy) and hypertension (HP) in Tg2576 mice. We have shown that carbonic anhydrase inhibitors (CAi) decreased vascular amyloid accumulation and neuroinflammation and prevented cognitive impairment in TgSwDI mice. Here, we evaluated the effects of HP and HHcy in AD and CAA pathology. In addition, we assessed the beneficial effects of CAi in the Tg2576 with/without the presence of VRF. Methods To induce VRF, male and female WT and Tg2576 mice were fed a HHcy inducing diet and/or were given L-NAME (NO inhibitor to induce HP) in the water starting at 5 months of age. To test the effects of CAi, the FDA-approved CAi (Acetazolamide) was added to the diet starting at 5 months of age. Animals were then tested in a battery of behavioral measures including spatial learning and memory (barnes maze, fear conditioning, novel object recognition, open field, and rotarod), at 12 months of age. Result The presence of HHcy or HT worsens spatial learning and memory in the WT and Tg2576 mice. Preliminary results may suggest that treatment with CAi improved spatial learning and memory in the WT and Tg2576 mice, in the presence or absence of VRFs. Conclusion Taken together, our results suggest that VRF affect learning and memory in AD/CAA and non-AD/CAA animal models. Importantly, we demonstrate that CAi is a promising treatment for treating mixed AD and CAA pathology.Item Open Access Understanding the Impact of Mild Episodic Memory Difficulties on Everyday Tasks in Older Adults(2025-01-03)Background The Goal-Control Model posits that episodic memory impairment leads to premature decay of everyday task goals, which contributes to task omissions (failure to accomplish task steps) in those with moderate to severe impairment. Although task omissions are not observed in those with mild episodic memory (mildEM) impairment, it has yet to be investigated if goal decay is reflected by subtle errors during task completion. We hypothesized that goal decay in mildEM impairment is reflected by imprecision in task performance at the end of everyday tasks. Method 54 participants (M age = 73; 39 healthy control [HC], 15 MCI/mild dementia) were videorecorded while preparing a breakfast and a lunch according to specific instructions (Naturalistic Action Task). Performance errors were classified by two coders and another organized them into segments occurring in the beginning, middle or end of the task, all blind to participant diagnosis and study hypothesis. Analyses compared errors in each segment between those with mildEM impairment (MCI/mild dementia) and HC. Correlation analyses examined relations between errors and demographically adjusted standard scores on tests of episodic memory (HVLT and BVMT-R delayed free recall) and executive function (Digits Backward, Trail Making Test B). Result Participants with mildEM impairment made significantly more errors than healthy controls only during the end task segment, t(52) = 2.83, p = .04. The groups did not differ in total errors during the beginning (p = .35) or middle task segments (p = .08). Correlations including the full sample showed significant relations between total errors during the end segment and scores on tests of episodic memory (HVLT r = -.33, p = .01; BVMT r = -.37, p <.01) but not scores on tests of executive function (Digits Backward r = .01, p = .92; TMT-B r = .01, p = .97). Conclusion Consistent with hypotheses informed by the Goal-Control Model, older adults with mildEM impairment exhibited increased imprecision towards the end of the task, suggesting that even those with mildEM deficits can experience premature decay of task goals. Behavioral strategies to strengthen goal activations, including reminder cues and/or overt verbalization of task goals, should be investigated as an avenue to improve everyday function in older adults with mild memory difficulties.