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Aditya Pratapa

Publications and source records attributed to Aditya Pratapa.

2 recordsLinked to original sources

Out of Distribution Generalization via Interventional Style Transfer in Single-Cell Microscopy

Real-world deployment of computer vision systems, including in the discovery processes of biomedical research, requires causal representations that are invariant to contextual nuisances and generalize to new data. Leveraging the internal replicate structure of two novel single-cell fluorescent microscopy datasets, we propose generally applicable tests to assess the extent to which models learn causal representations across increasingly challenging levels of OOD-generalization. We show that despite seemingly strong performance, as assessed by other established metrics, both naive and contemporary baselines designed to ward against confounding, collapse on these tests. We introduce a new method, Interventional Style Transfer (IST), that substantially improves OOD generalization by generating interventional training distributions in which spurious correlations between biological causes and nuisances are mitigated. We publish our code and datasets.

cs.CV

Fast-SL: An efficient algorithm to identify synthetic lethal reaction sets in metabolic networks

Synthetic lethal reaction/gene-sets are sets of reactions/genes where only the simultaneous removal of all reactions/genes in the set abolishes growth of an organism. In silico, synthetic lethal sets can be identified by simulating the effect of removal of gene sets from the reconstructed genome-scale metabolic network of an organism. Flux balance analysis (FBA), based on linear programming, has emerged as a powerful tool for the in silico analyses of metabolic networks. To identify all possible synthetic lethal reactions combinations, an exhaustive sampling of all possible combinations is computationally expensive. We surmount the computational complexity of exhaustive search by iteratively restricting the sample space of reaction combinations for search, resulting in a substantial reduction in the running time. We here propose an algorithm, Fast-SL, which provides an efficient way to analyse metabolic networks for higher order lethal reaction sets. Fast-SL offers a substantial speed-up through a massive reduction in the search space for synthetic lethals; in the case of E. coli, Fast-SL reduces the search space for synthetic lethal triplets by over 4000-fold. Fast-SL also compares favourably with SL Finder, an algorithm for identifying synthetic lethal sets, by Suthers et al (2009), which involves the solution of a bi-level Mixed Integer Linear Programming problem. We have implemented the Fast-SL algorithm in MATLAB, building upon COBRA toolbox v2.0.

q-bio.MN