33 research outputs found
ChemRL-GEM: Geometry Enhanced Molecular Representation Learning for Property Prediction
Effective molecular representation learning is of great importance to
facilitate molecular property prediction, which is a fundamental task for the
drug and material industry. Recent advances in graph neural networks (GNNs)
have shown great promise in applying GNNs for molecular representation
learning. Moreover, a few recent studies have also demonstrated successful
applications of self-supervised learning methods to pre-train the GNNs to
overcome the problem of insufficient labeled molecules. However, existing GNNs
and pre-training strategies usually treat molecules as topological graph data
without fully utilizing the molecular geometry information. Whereas, the
three-dimensional (3D) spatial structure of a molecule, a.k.a molecular
geometry, is one of the most critical factors for determining molecular
physical, chemical, and biological properties. To this end, we propose a novel
Geometry Enhanced Molecular representation learning method (GEM) for Chemical
Representation Learning (ChemRL). At first, we design a geometry-based GNN
architecture that simultaneously models atoms, bonds, and bond angles in a
molecule. To be specific, we devised double graphs for a molecule: The first
one encodes the atom-bond relations; The second one encodes bond-angle
relations. Moreover, on top of the devised GNN architecture, we propose several
novel geometry-level self-supervised learning strategies to learn spatial
knowledge by utilizing the local and global molecular 3D structures. We compare
ChemRL-GEM with various state-of-the-art (SOTA) baselines on different
molecular benchmarks and exhibit that ChemRL-GEM can significantly outperform
all baselines in both regression and classification tasks. For example, the
experimental results show an overall improvement of 8.8% on average compared to
SOTA baselines on the regression tasks, demonstrating the superiority of the
proposed method
HelixFold-Single: MSA-free Protein Structure Prediction by Using Protein Language Model as an Alternative
AI-based protein structure prediction pipelines, such as AlphaFold2, have
achieved near-experimental accuracy. These advanced pipelines mainly rely on
Multiple Sequence Alignments (MSAs) as inputs to learn the co-evolution
information from the homologous sequences. Nonetheless, searching MSAs from
protein databases is time-consuming, usually taking dozens of minutes.
Consequently, we attempt to explore the limits of fast protein structure
prediction by using only primary sequences of proteins. HelixFold-Single is
proposed to combine a large-scale protein language model with the superior
geometric learning capability of AlphaFold2. Our proposed method,
HelixFold-Single, first pre-trains a large-scale protein language model (PLM)
with thousands of millions of primary sequences utilizing the self-supervised
learning paradigm, which will be used as an alternative to MSAs for learning
the co-evolution information. Then, by combining the pre-trained PLM and the
essential components of AlphaFold2, we obtain an end-to-end differentiable
model to predict the 3D coordinates of atoms from only the primary sequence.
HelixFold-Single is validated in datasets CASP14 and CAMEO, achieving
competitive accuracy with the MSA-based methods on the targets with large
homologous families. Furthermore, HelixFold-Single consumes much less time than
the mainstream pipelines for protein structure prediction, demonstrating its
potential in tasks requiring many predictions. The code of HelixFold-Single is
available at
https://github.com/PaddlePaddle/PaddleHelix/tree/dev/apps/protein_folding/helixfold-single,
and we also provide stable web services on
https://paddlehelix.baidu.com/app/drug/protein-single/forecast
Pre-Training on Large-Scale Generated Docking Conformations with HelixDock to Unlock the Potential of Protein-ligand Structure Prediction Models
Protein-ligand structure prediction is an essential task in drug discovery,
predicting the binding interactions between small molecules (ligands) and
target proteins (receptors). Although conventional physics-based docking tools
are widely utilized, their accuracy is compromised by limited conformational
sampling and imprecise scoring functions. Recent advances have incorporated
deep learning techniques to improve the accuracy of structure prediction.
Nevertheless, the experimental validation of docking conformations remains
costly, it raises concerns regarding the generalizability of these deep
learning-based methods due to the limited training data. In this work, we show
that by pre-training a geometry-aware SE(3)-Equivariant neural network on a
large-scale docking conformation generated by traditional physics-based docking
tools and then fine-tuning with a limited set of experimentally validated
receptor-ligand complexes, we can achieve outstanding performance. This process
involved the generation of 100 million docking conformations, consuming roughly
1 million CPU core days. The proposed model, HelixDock, aims to acquire the
physical knowledge encapsulated by the physics-based docking tools during the
pre-training phase. HelixDock has been benchmarked against both physics-based
and deep learning-based baselines, showing that it outperforms its closest
competitor by over 40% for RMSD. HelixDock also exhibits enhanced performance
on a dataset that poses a greater challenge, thereby highlighting its
robustness. Moreover, our investigation reveals the scaling laws governing
pre-trained structure prediction models, indicating a consistent enhancement in
performance with increases in model parameters and pre-training data. This
study illuminates the strategic advantage of leveraging a vast and varied
repository of generated data to advance the frontiers of AI-driven drug
discovery
Intelligent Biosensors for Healthcare 5.0
Increasing demands for smart health management driven by aging population and chronic diseases are transforming traditional healthcare delivery into intelligent and personalized ones. However, some critical issues still exist in the development of intelligent biosensors towards the new era of healthcare 5.0, such as the design and fabrication of highly integrated biosensing devices, the exploitation of artificial intelligence (AI) and internet of things (IoT), the complete realization of smart disease control and health management, etc. Recent advances have explored the feasibility of miniaturized and portable biosensing device for household diagnostics, whereas the integration of IoT and AI is an unmet challenge. Hence, this chapter summarizes promising on-going efforts with emphasis on two domains: electrochemistry and spectroscopy. State-of-the-art intelligent biosensors are presented and insights in prospective exploration directions are discussed in the context of Healthcare 5.0
Combining Resource, Structure and Institutional Environment: A Configurational Approach to the Mode Selection of the Integrated Healthcare in County
Integrated healthcare has received considerable attention and has developed into the highly important health policy known as Integrated Healthcare in County (IHC) against the background of the Grading Diagnosis and Treatment System (GDTS) in rural China. However, the causal conditions under which different integrated health-care modes might be selected are poorly understood, particularly in the context of China’s authoritarian regime. This study aims to identify these causal conditions, and how they shape the mode selection mechanism for Integrated Healthcare in County (IHC). A theoretical framework consisting of resource heterogeneity, governance structure, and institutional normalization was proposed, and a sample of fifteen IHCs was selected, with data for each IHC being collected from news reports, work reports, government documents and field research for Fuzzy-sets Qualitative Comparative Analysis (fsQCA). This study firstly pointed out that strong governmental control and centralization are necessary conditions for the administration-oriented organization mode (MOA). Additionally, this research found three critical configured paths in the selection of organizational modes. Specifically, we found that the combination of low resource heterogeneity, weak governmental control, centralization, and normalization was sufficient to explain the selection path of the insurance-driven organization mode (MOI); the combination of low resource heterogeneity, strong governmental control, centralization, and normalization was sufficient for selecting MOA; and the combination of weak governmental control, weak centralization, and weak normalization was sufficient for selecting the contractual organization mode (MOC). Our study highlighted the necessity and feasibility of constructing different IHC modes separately and promoting their development gradually, as a result of the complex relationships among the causal conditions described above, thus helping to optimize the distribution of health resources and integrate the healthcare system
An Overview of the Science Performances and Calibration/Validation of Joint Polar Satellite System Operational Products
The Suomi National Polar-orbiting Partnership (S-NPP) satellite, launched in October 2011, initiated a series of the next-generation weather satellites for the National Oceanic and Atmospheric Administration (NOAA) Joint Polar Satellite System (JPSS) program. The JPSS program at the Center for Satellite Applications and Research (JSTAR) leads the development of the algorithms, the calibration and validation of the products to meet the specified requirements, and long-term science performance monitoring and maintenance. All of the S-NPP products have been validated and are in successful operation. The recently launched JPSS-1 (renamed as NOAA-20) satellite is producing high-quality data products that have been available from S-NPP, along with additional products, as a direct result of the instrument upgrades and science improvements. This paper presents an overview of the JPSS product suite, the performance metrics achieved for the S-NPP, and the utilization of the products by NOAA stakeholders and user agencies worldwide. The status of NOAA-20 science data products and ongoing calibration/validation (Cal/Val) efforts are discussed for user awareness. In addition, operational implementation statuses of JPSS enterprise (multisensor and multiplatform) science algorithms for product generation and science product reprocessing efforts for the S-NPP mission are discussed