Portrait de Chenghao Liu n'est pas disponible

Chenghao Liu

Collaborateur·rice alumni
Superviseur⋅e principal⋅e

Publications

Iterated Denoising Energy Matching for Sampling from Boltzmann Densities
Tara Akhound-Sadegh
Jarrid Rector-Brooks
Joey Bose
Sarthak Mittal
Pablo Lemos
Cheng-Hao Liu
Marcin Sendera
Nikolay Malkin
Alexander Tong
Efficiently generating statistically independent samples from an unnormalized probability distribution, such as equilibrium samples of many-… (voir plus)body systems, is a foundational problem in science. In this paper, we propose Iterated Denoising Energy Matching (iDEM), an iterative algorithm that uses a novel stochastic score matching objective leveraging solely the energy function and its gradient---and no data samples---to train a diffusion-based sampler. Specifically, iDEM alternates between (I) sampling regions of high model density from a diffusion-based sampler and (II) using these samples in our stochastic matching objective to further improve the sampler. iDEM is scalable to high dimensions as the inner matching objective, is *simulation-free*, and requires no MCMC samples. Moreover, by leveraging the fast mode mixing behavior of diffusion, iDEM smooths out the energy landscape enabling efficient exploration and learning of an amortized sampler. We evaluate iDEM on a suite of tasks ranging from standard synthetic energy functions to invariant
Integrating Generative and Experimental Platforms or Biomolecular Design
Cheng-Hao Liu
Jarrid Rector-Brooks
Jason Yim
Soojung Yang
Sidney Lisanza
Francesca-Zhoufan Li
Pranam Chatterjee
Tommi Jaakkola
Regina Barzilay
David Baker
Frances H. Arnold
Iterated Denoising Energy Matching for Sampling from Boltzmann Densities
Tara Akhound-Sadegh
Jarrid Rector-Brooks
Joey Bose
Sarthak Mittal
Pablo Lemos
Cheng-Hao Liu
Marcin Sendera
Nikolay Malkin
Alexander Tong
Efficiently generating statistically independent samples from an unnormalized probability distribution, such as equilibrium samples of many-… (voir plus)body systems, is a foundational problem in science. In this paper, we propose Iterated Denoising Energy Matching (iDEM), an iterative algorithm that uses a novel stochastic score matching objective leveraging solely the energy function and its gradient -- and no data samples -- to train a diffusion-based sampler. Specifically, iDEM alternates between (I) sampling regions of high model density from a diffusion-based sampler and (II) using these samples in our stochastic matching objective to further improve the sampler. iDEM is scalable to high dimensions as the inner matching objective, is simulation-free, and requires no MCMC samples. Moreover, by leveraging the fast mode mixing behavior of diffusion, iDEM smooths out the energy landscape enabling efficient exploration and learning of an amortized sampler. We evaluate iDEM on a suite of tasks ranging from standard synthetic energy functions to invariant
Diffusion Generative Flow Samplers: Improving learning signals through partial trajectory optimization
Dinghuai Zhang
Ricky T. Q. Chen
Cheng-Hao Liu
Multi-Fidelity Active Learning with GFlowNets
Alex Hernandez-Garcia
Nikita Saxena
Moksh J. Jain
Cheng-Hao Liu
In the last decades, the capacity to generate large amounts of data in science and engineering applications has been growing steadily. Meanw… (voir plus)hile, the progress in machine learning has turned it into a suitable tool to process and utilise the available data. Nonetheless, many relevant scientific and engineering problems present challenges where current machine learning methods cannot yet efficiently leverage the available data and resources. For example, in scientific discovery, we are often faced with the problem of exploring very large, high-dimensional spaces, where querying a high fidelity, black-box objective function is very expensive. Progress in machine learning methods that can efficiently tackle such problems would help accelerate currently crucial areas such as drug and materials discovery. In this paper, we propose the use of GFlowNets for multi-fidelity active learning, where multiple approximations of the black-box function are available at lower fidelity and cost. GFlowNets are recently proposed methods for amortised probabilistic inference that have proven efficient for exploring large, high-dimensional spaces and can hence be practical in the multi-fidelity setting too. Here, we describe our algorithm for multi-fidelity active learning with GFlowNets and evaluate its performance in both well-studied synthetic tasks and practically relevant applications of molecular discovery. Our results show that multi-fidelity active learning with GFlowNets can efficiently leverage the availability of multiple oracles with different costs and fidelities to accelerate scientific discovery and engineering design.
Towards equilibrium molecular conformation generation with GFlowNets
Alexandra Volokhova
Michał Koziarski
Alex Hernandez-Garcia
Cheng-Hao Liu
Santiago Miret
Pablo Lemos
Luca Thiede
Zichao Yan
Alán Aspuru-Guzik
Sampling diverse, thermodynamically feasible molecular conformations plays a crucial role in predicting properties of a molecule. In this pa… (voir plus)per we propose to use GFlowNet for sampling conformations of small molecules from the Boltzmann distribution, as determined by the molecule's energy. The proposed approach can be used in combination with energy estimation methods of different fidelity and discovers a diverse set of low-energy conformations for highly flexible drug-like molecules. We demonstrate that GFlowNet can reproduce molecular potential energy surfaces by sampling proportionally to the Boltzmann distribution.
A community effort in SARS-CoV-2 drug discovery.
Johannes Schimunek
Philipp Seidl
Katarina Elez
Tim Hempel
Tuan Le
Frank Noé
Simon Olsson
Lluís Raich
Robin Winter
Hatice Gokcan
Filipp Gusev
Evgeny M. Gutkin
Olexandr Isayev
Maria G. Kurnikova
Chamali H. Narangoda
Roman Zubatyuk
Ivan P. Bosko
Konstantin V. Furs
Anna D. Karpenko
Yury V. Kornoushenko … (voir 133 de plus)
Mikita Shuldau
Artsemi Yushkevich
Mohammed B. Benabderrahmane
Patrick Bousquet‐Melou
Ronan Bureau
Beatrice Charton
Bertrand C. Cirou
Gérard Gil
William J. Allen
Suman Sirimulla
Stanley Watowich
Nick Antonopoulos
Nikolaos Epitropakis
Agamemnon Krasoulis
Vassilis Pitsikalis
Stavros Theodorakis
Igor Kozlovskii
Anton Maliutin
Alexander Medvedev
Petr Popov
Mark Zaretckii
Hamid Eghbal‐Zadeh
Christina Halmich
Sepp Hochreiter
Andreas Mayr
Peter Ruch
Michael Widrich
Francois Berenger
Ashutosh Kumar
Yoshihiro Yamanishi
Kam Y. J. Zhang
Emmanuel Bengio
Moksh J. Jain
Maksym Korablyov
Cheng-Hao Liu
Gilles Marcou
Marcous Gilles
Enrico Glaab
Kelly Barnsley
Suhasini M. Iyengar
Mary Jo Ondrechen
V. Joachim Haupt
Florian Kaiser
Michael Schroeder
Luisa Pugliese
Simone Albani
Christina Athanasiou
Andrea Beccari
Paolo Carloni
Giulia D'Arrigo
Eleonora Gianquinto
Jonas Goßen
Anton Hanke
Benjamin P. Joseph
Daria B. Kokh
Sandra Kovachka
Candida Manelfi
Goutam Mukherjee
Abraham Muñiz‐Chicharro
Francesco Musiani
Ariane Nunes‐Alves
Giulia Paiardi
Giulia Rossetti
S. Kashif Sadiq
Francesca Spyrakis
Carmine Talarico
Alexandros Tsengenes
Rebecca C. Wade
Conner Copeland
Jeremiah Gaiser
Daniel R. Olson
Amitava Roy
Vishwesh Venkatraman
Travis J. Wheeler
Haribabu Arthanari
Klara Blaschitz
Marco Cespugli
Vedat Durmaz
Konstantin Fackeldey
Patrick D. Fischer
Christoph Gorgulla
Christian Gruber
Karl Gruber
Michael Hetmann
Jamie E. Kinney
Krishna M. Padmanabha Das
Shreya Pandita
Amit Singh
Georg Steinkellner
Guilhem Tesseyre
Gerhard Wagner
Zi‐Fu Wang
Ryan J. Yust
Dmitry S. Druzhilovskiy
Dmitry A. Filimonov
Pavel V. Pogodin
Vladimir Poroikov
Anastassia V. Rudik
Leonid A. Stolbov
Alexander V. Veselovsky
Maria De Rosa
Giada De Simone
Maria R. Gulotta
Jessica Lombino
Nedra Mekni
Ugo Perricone
Arturo Casini
Amanda Embree
D. Benjamin Gordon
David Lei
Katelin Pratt
Christopher A. Voigt
Kuang‐Yu Chen
Yves Jacob
Tim Krischuns
Pierre Lafaye
Agnès Zettor
M. Luis Rodríguez
Kris M. White
Daren Fearon
Frank Von Delft
Martin A. Walsh
Dragos Horvath
Charles L. Brooks
Babak Falsafi
Bryan Ford
Adolfo García‐Sastre
Sang Yup Lee
Nadia Naffakh
Alexandre Varnek
Günter Klambauer
Thomas M. Hermans
The COVID-19 pandemic continues to pose a substantial threat to human lives and is likely to do so for years to come. Despite the availabili… (voir plus)ty of vaccines, searching for efficient small-molecule drugs that are widely available, including in low- and middle-income countries, is an ongoing challenge. In this work, we report the results of an open science community effort, the "Billion molecules against Covid-19 challenge", to identify small-molecule inhibitors against SARS-CoV-2 or relevant human receptors. Participating teams used a wide variety of computational methods to screen a minimum of 1 billion virtual molecules against 6 protein targets. Overall, 31 teams participated, and they suggested a total of 639,024 molecules, which were subsequently ranked to find 'consensus compounds'. The organizing team coordinated with various contract research organizations (CROs) and collaborating institutions to synthesize and test 878 compounds for biological activity against proteases (Nsp5, Nsp3, TMPRSS2), nucleocapsid N, RdRP (only the Nsp12 domain), and (alpha) spike protein S. Overall, 27 compounds with weak inhibition/binding were experimentally identified by binding-, cleavage-, and/or viral suppression assays and are presented here. Open science approaches such as the one presented here contribute to the knowledge base of future drug discovery efforts in finding better SARS-CoV-2 treatments.
Thompson Sampling for Improved Exploration in GFlowNets
Jarrid Rector-Brooks
Kanika Madan
Moksh J. Jain
Maksym Korablyov
Cheng-Hao Liu
Nikolay Malkin
Generative flow networks (GFlowNets) are amortized variational inference algorithms that treat sampling from a distribution over composition… (voir plus)al objects as a sequential decision-making problem with a learnable action policy. Unlike other algorithms for hierarchical sampling that optimize a variational bound, GFlowNet algorithms can stably run off-policy, which can be advantageous for discovering modes of the target distribution. Despite this flexibility in the choice of behaviour policy, the optimal way of efficiently selecting trajectories for training has not yet been systematically explored. In this paper, we view the choice of trajectories for training as an active learning problem and approach it using Bayesian techniques inspired by methods for multi-armed bandits. The proposed algorithm, Thompson sampling GFlowNets (TS-GFN), maintains an approximate posterior distribution over policies and samples trajectories from this posterior for training. We show in two domains that TS-GFN yields improved exploration and thus faster convergence to the target distribution than the off-policy exploration strategies used in past work.
GFlowNets for AI-Driven Scientific Discovery
Moksh J. Jain
Tristan Deleu
Jason Hartford
Cheng-Hao Liu
Alex Hernandez-Garcia
Tackling the most pressing problems for humanity, such as the climate crisis and the threat of global pandemics, requires accelerating the p… (voir plus)ace of scientific discovery. While science has traditionally relied...
E VALUATING G ENERALIZATION IN GF LOW N ETS FOR M OLECULE D ESIGN
Andrei Cristian Nica
Moksh J. Jain
Emmanuel Bengio
Cheng-Hao Liu
Maksym Korablyov
Michael M. Bronstein
Deep learning bears promise for drug discovery problems such as de novo molecular design. Generating data to train such models is a costly a… (voir plus)nd time-consuming process, given the need for wet-lab experiments or expensive simulations. This problem is compounded by the notorious data-hungriness of machine learning algorithms. In small molecule generation the recently proposed GFlowNet method has shown good performance in generating diverse high-scoring candidates, and has the interesting advantage of being an off-policy offline method. Finding an appropriate generalization evaluation metric for such models, one predictive of the desired search performance (i.e. finding high-scoring diverse candidates), will help guide online data collection for such an algorithm. In this work, we develop techniques for evaluating GFlowNet performance on a test set, and identify the most promising metric for predicting generalization. We present empirical results on several small-molecule design tasks in drug discovery, for several GFlowNet training setups, and we find a metric strongly correlated with diverse high-scoring batch generation. This metric should be used to identify the best generative model from which to sample batches of molecules to be evaluated.