49 research outputs found
Observation of superabsorption by correlated atoms
Emission and absorption of light lie at the heart of light-matter
interaction. Although the emission and absorption rates are regarded as
intrinsic properties of atoms and molecules, various ways to modify these rates
have been sought in critical applications such as quantum information
processing, metrology and light-energy harvesting. One of the promising
approaches is to utilize collective behavior of emitters as in superradiance.
Although superradiance has been observed in diverse systems, its conceptual
counterpart in absorption has never been realized. Here, we demonstrate
superabsorption, enhanced cooperative absorption, by correlated atoms of
phase-matched superposition state. By implementing an
opposite-phase-interference idea on a superradiant state or equivalently a
time-reversal process of superradiance, we realized the superabsorption with
its absorption rate much faster than that of the ordinary ground-state
absorption. The number of photons completely absorbed for a given time interval
was measured to be proportional to the square of the number of atoms. Our
approach, breaking the limitation of the conventional absorption, can help
weak-signal sensing and advance efficient light-energy harvesting as well as
light-matter quantum interfaces.Comment: 7 pages, 5 figure
Bespoke Nanoparticle Synthesis and Chemical Knowledge Discovery Via Autonomous Experimentations
The optimization of nanomaterial synthesis using numerous synthetic variables
is considered to be extremely laborious task because the conventional
combinatorial explorations are prohibitively expensive. In this work, we report
an autonomous experimentation platform developed for the bespoke design of
nanoparticles (NPs) with targeted optical properties. This platform operates in
a closed-loop manner between a batch synthesis module of NPs and a UV- Vis
spectroscopy module, based on the feedback of the AI optimization modeling.
With silver (Ag) NPs as a representative example, we demonstrate that the
Bayesian optimizer implemented with the early stopping criterion can
efficiently produce Ag NPs precisely possessing the desired absorption spectra
within only 200 iterations (when optimizing among five synthetic reagents). In
addition to the outstanding material developmental efficiency, the analysis of
synthetic variables further reveals a novel chemistry involving the effects of
citrate in Ag NP synthesis. The amount of citrate is a key to controlling the
competitions between spherical and plate-shaped NPs and, as a result, affects
the shapes of the absorption spectra as well. Our study highlights both
capabilities of the platform to enhance search efficiencies and to provide a
novel chemical knowledge by analyzing datasets accumulated from the autonomous
experimentations
Ubiquitination and degradation of SUMO1 by small-molecule degraders extends survival of mice with patient-derived tumors
Discovery of small-molecule degraders that activate ubiquitin ligase–mediated ubiquitination and degradation of targeted oncoproteins in cancer cells has been an elusive therapeutic strategy. Here, we report a cancer cell–based drug screen of the NCI drug-like compounds library that enabled identification of small-molecule degraders of the small ubiquitin-related modifier 1 (SUMO1). Structure-activity relationship studies of analogs of the hit compound CPD1 led to identification of a lead compound HB007 with improved properties and anticancer potency in vitro and in vivo. A genome-scale CRISPR-Cas9 knockout screen identified the substrate receptor F-box protein 42 (FBXO42) of cullin 1 (CUL1) E3 ubiquitin ligase as required for HB007 activity. Using HB007 pull-down proteomics assays, we pinpointed HB007’s binding protein as the cytoplasmic activation/proliferation-associated protein 1 (CAPRIN1). Biolayer interferometry and compound competitive immunoblot assays confirmed the selectivity of HB007’s binding to CAPRIN1. When bound to CAPRIN1, HB007 induced the interaction of CAPRIN1 with FBXO42. FBXO42 then recruited SUMO1 to the CAPRIN1-CUL1-FBXO42 ubiquitin ligase complex, where SUMO1 was ubiquitinated in several of human cancer cells. HB007 selectively degraded SUMO1 in patient tumor–derived xenografts implanted into mice. Systemic administration of HB007 inhibited the progression of patient-derived brain, breast, colon, and lung cancers in mice and increased survival of the animals. This cancer cell–based screening approach enabled discovery of a small-molecule degrader of SUMO1 and may be useful for identifying other small-molecule degraders of oncoproteins
Proceedings of the 29th EG-ICE International Workshop on Intelligent Computing in Engineering
This publication is the Proceedings of the 29th EG-ICE International Workshop on Intelligent Computing in Engineering from July 6-8, 2022. The EG-ICE International Workshop on Intelligent Computing in Engineering brings together international experts working on the interface between advanced computing and modern engineering challenges. Many engineering tasks require open-world resolution of challenges such as supporting multi-actor collaboration, coping with approximate models, providing effective engineer-computer interaction, search in multi-dimensional solution spaces, accommodating uncertainty, including specialist domain knowledge, performing sensor-data interpretation and dealing with incomplete knowledge. While results from computer science provide much initial support for resolution, adaptation is unavoidable and most importantly, feedback from addressing engineering challenges drives fundamental computer-science research. Competence and knowledge transfer goes both ways.