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Designing an efficient arithmetic division circuit has long been a major challenge. Traditional binary computation methods rely on complex algorithms that require multiple cycles, complex control logic, and substantial hardware resources. Implementing division with emerging in-memory computing technologies is even more challenging due to susceptibility to noise, process variation, and the complexity of binary division. In this work, we propose an in-memory division architecture leveraging stochastic computing (SC), an emerging technology known for its high fault tolerance and low-cost design. Our approach utilizes a magnetic tunnel junction (MTJ)-based memory architecture to efficiently execute logic-in-memory operations. Experimental results across various process variation conditions demonstrate the robustness of our method against hardware variations. To assess its practical effectiveness, we apply our approach to the Retinex Algorithm for image enhancement, demonstrating its viability in real-world applications. 

Bias in neural network model training datasets has been observed to decrease prediction accuracy for groups underrepresented in training data. Thus, investigating the composition of training datasets used in machine learning models with healthcare applications is vital to ensure equity. Two such machine learning models are NetMHCpan-4.1 and NetMHCIIpan-4.0, used to predict antigen binding scores to major histocompatibility complex class I and II molecules, respectively. As antigen presentation is a critical step in mounting the adaptive immune response, previous work has used these or similar predictions models in a broad array of applications, from explaining asymptomatic viral infection to cancer neoantigen prediction. However, these models have also been shown to be biased toward hydrophobic peptides, suggesting the network could also contain other sources of bias. Here, we report the composition of the networks’ training datasets are heavily biased toward European Caucasian individuals and against Asian and Pacific Islander individuals. We test the ability of NetMHCpan-4.1 and NetMHCpan-4.0 to distinguish true binders from randomly generated peptides on alleles not included in the training datasets. Unexpectedly, we fail to find evidence that the disparities in training data lead to a meaningful difference in prediction quality for alleles not present in the training data. We attempt to explain this result by mapping the HLA sequence space to determine the sequence diversity of the training dataset. Furthermore, we link the residues which have the greatest impact on NetMHCpan predictions to structural features for three alleles (HLA-A*34:01, HLA-C*04:03, HLA-DRB1*12:02). 

Automated routing of droplets for DNA storage on an industrial-scale digital microfluidics platform. 

Abstract Acid-base reactions are ubiquitous, easy to prepare, and execute without sophisticated equipment. Acids and bases are also inherently complementary and naturally map to a universal representation of “0” and “1.” Here, we propose how to leverage acids, bases, and their reactions to encode binary information and perform information processing based upon the majority and negation operations. These operations form a functionally complete set that we use to implement more complex computations such as digital circuits and neural networks. We present the building blocks needed to build complete digital circuits using acids and bases for dual-rail encoding data values as complementary pairs, including a set of primitive logic functions that are widely applicable to molecular computation. We demonstrate how to implement neural network classifiers and some classes of digital circuits with acid-base reactions orchestrated by a robotic fluid handling device. We validate the neural network experimentally on a number of images with different formats, resulting in a perfect match to thein-silicoclassifier. Additionally, the simulation of our acid-base classifier matches the results of thein-silicoclassifier with approximately 99% similarity.