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Creators/Authors contains: "Hayes, Nicole"

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  1. AI-driven drug discovery accelerates anti-addiction treatment by enhancing precision and targeting key neurochemical systems. 
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  2. Imbalanced data, where certain classes are significantly underrepresented in a dataset, is a widespread machine learning (ML) challenge across various fields of chemistry, yet it remains inadequately addressed. 
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  3. Data sets with imbalanced class sizes, where one class size is much smaller than that of others, occur exceedingly often in many applications, including those with biological foundations, such as disease diagnosis and drug discovery. Therefore, it is extremely important to be able to identify data elements of classes of various sizes, as a failure to do so can result in heavy costs. Nonetheless, many data classification procedures do not perform well on imbalanced data sets as they often fail to detect elements belonging to underrepresented classes. In this work, we propose the BTDT-MBO algorithm, incorporating Merriman–Bence–Osher (MBO) approaches and a bidirectional transformer, as well as distance correlation and decision threshold adjustments, for data classification tasks on highly imbalanced molecular data sets, where the sizes of the classes vary greatly. The proposed technique not only integrates adjustments in the classification threshold for the MBO algorithm in order to help deal with the class imbalance, but also uses a bidirectional transformer procedure based on an attention mechanism for self-supervised learning. In addition, the model implements distance correlation as a weight function for the similarity graph-based framework on which the adjusted MBO algorithm operates. The proposed method is validated using six molecular data sets and compared to other related techniques. The computational experiments show that the proposed technique is superior to competing approaches even in the case of a high class imbalance ratio. 
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  4. ABSTRACT Although nitrogen and phosphorus deficiency of algal blooms have been the focus of substantial attention, organic nutrients can limit algal growth in aquatic systems. Growing evidence indicates thiamine (vitamin B1) can influence the community of primary producers in marine systems, but comparatively little is known about the effect of thiamine on freshwater algal productivity.We conducted 106 nutrient deficiency experiments with water from 39 Ohio lakes of varying trophic status during the growing seasons (April–October) of 2008–2009. Specifically, we tested the response of phytoplankton biomass (as chlorophylla, chl‐a) relative to controls to added nitrogen (N), phosphorus (P), thiamine (Th), or combinations of N + P and N + P + Th. Next, we compared the chl‐agrowth response of treatment/control to published thresholds based on frequentist approaches and compared the conclusions with Bayesian model results that focused on probability of a response.Although N + P addition was consistently associated with the largest chl‐aresponse, we found evidence of a thiamine influence on phytoplankton growth in some experiments. The Bayesian approach suggested thiamine may become more limiting as the growing season progresses. By late in the growing season, there was an 85% probability of a positive algal growth response to thiamine addition.Understanding the role of thiamine or other overlooked nutrients is not likely to alter the prevailing understanding of nutrient deficiency in freshwater ecosystems. However, we present evidence that freshwater phytoplankton may experience thiamine deficiency and suggest limnologists consider thiamine when exploring resource deficiencies. 
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  5. Cybersickness – discomfort caused by virtual reality (VR) – remains a significant problem that negatively affects the user experience. Research on individual differences in cybersickness has typically focused on overall sickness intensity, but a detailed understanding should include whether individuals differ in the relative intensity of cybersickness symptoms. This study used latent profile analysis (LPA) to explore whether there exist groups of individuals who experience common patterns of cybersickness symptoms. Participants played a VR game for up to 20 min. LPA indicated three groups with low, medium, and high overall cybersickness. Further, there were similarities and differences in relative patterns of nausea, disorientation, and oculomotor symptoms between groups. Disorientation was lower than nausea and oculomotor symptoms for all three groups. Nausea and oculomotor were experienced at similar levels within the high and low sickness groups, but the medium sickness group experienced more nausea than oculomotor. Characteristics of group members varied across groups, including gender, virtual reality experience, video game experience, and history of motion sickness. These findings identify distinct individual experiences in symptomology that go beyond overall sickness intensity, which could enable future interventions that target certain groups of individuals and specific symptoms. 
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