17 research outputs found
Self-paced Weight Consolidation for Continual Learning
Continual learning algorithms which keep the parameters of new tasks close to
that of previous tasks, are popular in preventing catastrophic forgetting in
sequential task learning settings. However, 1) the performance for the new
continual learner will be degraded without distinguishing the contributions of
previously learned tasks; 2) the computational cost will be greatly increased
with the number of tasks, since most existing algorithms need to regularize all
previous tasks when learning new tasks. To address the above challenges, we
propose a self-paced Weight Consolidation (spWC) framework to attain robust
continual learning via evaluating the discriminative contributions of previous
tasks. To be specific, we develop a self-paced regularization to reflect the
priorities of past tasks via measuring difficulty based on key performance
indicator (i.e., accuracy). When encountering a new task, all previous tasks
are sorted from "difficult" to "easy" based on the priorities. Then the
parameters of the new continual learner will be learned via selectively
maintaining the knowledge amongst more difficult past tasks, which could well
overcome catastrophic forgetting with less computational cost. We adopt an
alternative convex search to iteratively update the model parameters and
priority weights in the bi-convex formulation. The proposed spWC framework is
plug-and-play, which is applicable to most continual learning algorithms (e.g.,
EWC, MAS and RCIL) in different directions (e.g., classification and
segmentation). Experimental results on several public benchmark datasets
demonstrate that our proposed framework can effectively improve performance
when compared with other popular continual learning algorithms
PYATB: An Efficient Python Package for Electronic Structure Calculations Using Ab Initio Tight-Binding Model
We present PYATB, a Python package designed for computing band structures and
related properties of materials using the ab initio tight-binding Hamiltonian.
The Hamiltonian is directly obtained after conducting self-consistent
calculations with first-principles packages using numerical atomic orbital
(NAO) bases, such as ABACUS. The package comprises three modules: Bands,
Geometric, and Optical. In the Bands module, one can calculate essential
properties of band structures, including the partial density of states (PDOS),
fat bands, Fermi surfaces, and Weyl/Dirac points. The band unfolding method is
utilized to obtain the energy band spectra of a supercell by projecting the
electronic structure of the supercell onto the Brillouin zone of the primitive
cell. With the Geometric module, one can compute the Berry phase and Berry
curvature-related quantities, such as electric polarization, Wilson loops,
Chern numbers, and anomalous Hall conductivities. The Optical module offers a
range of optical property calculations, including optical conductivity and
nonlinear optical responses, such as shift current and Berry curvature dipole
Block Coordinate Plug-and-Play Methods for Blind Inverse Problems
Plug-and-play (PnP) prior is a well-known class of methods for solving
imaging inverse problems by computing fixed-points of operators combining
physical measurement models and learned image denoisers. While PnP methods have
been extensively used for image recovery with known measurement operators,
there is little work on PnP for solving blind inverse problems. We address this
gap by presenting a new block-coordinate PnP (BC-PnP) method that efficiently
solves this joint estimation problem by introducing learned denoisers as priors
on both the unknown image and the unknown measurement operator. We present a
new convergence theory for BC-PnP compatible with blind inverse problems by
considering nonconvex data-fidelity terms and expansive denoisers. Our theory
analyzes the convergence of BC-PnP to a stationary point of an implicit
function associated with an approximate minimum mean-squared error (MMSE)
denoiser. We numerically validate our method on two blind inverse problems:
automatic coil sensitivity estimation in magnetic resonance imaging (MRI) and
blind image deblurring. Our results show that BC-PnP provides an efficient and
principled framework for using denoisers as PnP priors for jointly estimating
measurement operators and images
Self-Supervised Deep Equilibrium Models for Inverse Problems with Theoretical Guarantees
Deep equilibrium models (DEQ) have emerged as a powerful alternative to deep
unfolding (DU) for image reconstruction. DEQ models-implicit neural networks
with effectively infinite number of layers-were shown to achieve
state-of-the-art image reconstruction without the memory complexity associated
with DU. While the performance of DEQ has been widely investigated, the
existing work has primarily focused on the settings where groundtruth data is
available for training. We present self-supervised deep equilibrium model
(SelfDEQ) as the first self-supervised reconstruction framework for training
model-based implicit networks from undersampled and noisy MRI measurements. Our
theoretical results show that SelfDEQ can compensate for unbalanced sampling
across multiple acquisitions and match the performance of fully supervised DEQ.
Our numerical results on in-vivo MRI data show that SelfDEQ leads to
state-of-the-art performance using only undersampled and noisy training data
Pokemon Silencing Leads to Bim-Mediated Anoikis of Human Hepatoma Cell QGY7703
Pokemon is an important proto-oncogene that plays a critical role in cellular oncogenic transformation and tumorigenesis. Anoikis, which is regulated by Bim-mediated apoptosis, is critical to cancer cell invasion and metastasis. We investigated the role of Pokemon in anoikis, and our results show that Pokemon renders liver cells resistant to anoikis via suppression of Bim transcription. We knocked-down Pokemon in human hepatoma cells QGY7703 with small interfering RNAs (siRNA). Knockdown of Pokemon alone did not significantly affect the growth and survival of QGY7703 cells but notably enhanced their sensitivity to apoptotic stress due to the presence of chemical agents or cell detachment, thereby inducing anoikis, as evidenced by flow cytometry and caspase-3 activity assays. In contrast, ectopic expression of Pokemon in HL7702 cells led to resistance to anoikis. Dual-luciferase reporter and ChIP assays illustrated that Pokemon suppressed Bim transcription via direct binding to its promoter. Our results suggest that Pokemon prevents anoikis through the suppression of Bim expression, which facilitates tumor cell invasion and metastasis. This Pokemon-Bim pathway may be an effective target for therapeutic intervention for cancer
A Sustainable Dual Cross-Linked Cellulose Hydrogel Electrolyte for High-Performance Zinc-Metal Batteries
Highlights A sustainable dual cross-linked cellulose hydrogel with excellent mechanical strength was fabricated from aqueous alkali hydroxide/urea solution using a sequential chemical and physical cross-linking strategy. The hydrogel electrolyte effectively suppresses dendrites growth and side reactions to achieve a stable Zn anode (over 2000 h for Zn||Zn cell), which are proved by a multi-perspective and in-depth mechanism investigation. The hydrogel electrolyte is easily accessible and biodegradable, making the zinc batteries attractive in terms of scalability and sustainability
A Lightweight Sensitive Triboelectric Nanogenerator Sensor for Monitoring Loop Drive Technology in Table Tennis Training
As the Internet of Things becomes more and more mainstream, sensors are widely used in the field of motion monitoring. In this paper, we propose a lightweight and sensitive triboelectric nanogenerator (LS-TENG) consisting of transparent polytetrafluoroethylene (PTFE) and polyamide (PA) films as triboelectric layers, polydimethylsiloxane (PDMS) as support layer, and copper foil as electrode. LS-TENG can be attached to the joints of the human body, and the mechanical energy generated by human motion is converted into electric energy based on the triboelectric effect, thus realizing self-power supply. LS-TENG can monitor the angle changes in elbow and wrist joints when athletes pull the loop and actively generate the output voltage as a sensing signal, which is convenient for coaches to monitor the quality of athletes’ hitting in real time. In addition, LS-TENG can also be used as a power supply for other wireless electronic devices, which facilitates the construction and transmission of large motion data and opens up a new development direction for the field of motion monitoring
A Lightweight Sensitive Triboelectric Nanogenerator Sensor for Monitoring Loop Drive Technology in Table Tennis Training
As the Internet of Things becomes more and more mainstream, sensors are widely used in the field of motion monitoring. In this paper, we propose a lightweight and sensitive triboelectric nanogenerator (LS-TENG) consisting of transparent polytetrafluoroethylene (PTFE) and polyamide (PA) films as triboelectric layers, polydimethylsiloxane (PDMS) as support layer, and copper foil as electrode. LS-TENG can be attached to the joints of the human body, and the mechanical energy generated by human motion is converted into electric energy based on the triboelectric effect, thus realizing self-power supply. LS-TENG can monitor the angle changes in elbow and wrist joints when athletes pull the loop and actively generate the output voltage as a sensing signal, which is convenient for coaches to monitor the quality of athletes’ hitting in real time. In addition, LS-TENG can also be used as a power supply for other wireless electronic devices, which facilitates the construction and transmission of large motion data and opens up a new development direction for the field of motion monitoring