48,498 research outputs found
Computational structure‐based drug design: Predicting target flexibility
The role of molecular modeling in drug design has experienced a significant revamp in the last decade. The increase in computational resources and molecular models, along with software developments, is finally introducing a competitive advantage in early phases of drug discovery. Medium and small companies with strong focus on computational chemistry are being created, some of them having introduced important leads in drug design pipelines. An important source for this success is the extraordinary development of faster and more efficient techniques for describing flexibility in three‐dimensional structural molecular modeling. At different levels, from docking techniques to atomistic molecular dynamics, conformational sampling between receptor and drug results in improved predictions, such as screening enrichment, discovery of transient cavities, etc. In this review article we perform an extensive analysis of these modeling techniques, dividing them into high and low throughput, and emphasizing in their application to drug design studies. We finalize the review with a section describing our Monte Carlo method, PELE, recently highlighted as an outstanding advance in an international blind competition and industrial benchmarks.We acknowledge the BSC-CRG-IRB Joint Research Program in Computational Biology. This work was supported by a grant
from the Spanish Government CTQ2016-79138-R.J.I. acknowledges support from SVP-2014-068797, awarded by the Spanish Government.Peer ReviewedPostprint (author's final draft
Prospects and Limitations of Algorithmic Cooling
Heat-bath algorithmic cooling (AC) of spins is a theoretically powerful
effective cooling approach, that (ideally) cools spins with low polarization
exponentially better than cooling by reversible entropy manipulations alone.
Here, we investigate the limitations and prospects of AC. For non-ideal and
semioptimal AC, we study the impact of finite relaxation times of reset and
computation spins on the achievable effective cooling. We derive, via
simulations, the attainable cooling levels for given ratios of relaxation times
using two semioptimal practicable algorithms. We expect this analysis to be
valuable for the planning of future experiments. For ideal and optimal AC, we
make use of lower bounds on the number of required reset steps, based on
entropy considerations, to present important consequences of using AC as a tool
for improving signal-to-noise ratio in liquid-state magnetic resonance
spectroscopy. We discuss the potential use of AC for noninvasive clinical
diagnosis and drug monitoring, where it may have significantly lower specific
absorption rate (SAR) with respect to currently used methods.Comment: 12 pages, 5 figure
Solving ptychography with a convex relaxation
Ptychography is a powerful computational imaging technique that transforms a
collection of low-resolution images into a high-resolution sample
reconstruction. Unfortunately, algorithms that are currently used to solve this
reconstruction problem lack stability, robustness, and theoretical guarantees.
Recently, convex optimization algorithms have improved the accuracy and
reliability of several related reconstruction efforts. This paper proposes a
convex formulation of the ptychography problem. This formulation has no local
minima, it can be solved using a wide range of algorithms, it can incorporate
appropriate noise models, and it can include multiple a priori constraints. The
paper considers a specific algorithm, based on low-rank factorization, whose
runtime and memory usage are near-linear in the size of the output image.
Experiments demonstrate that this approach offers a 25% lower background
variance on average than alternating projections, the current standard
algorithm for ptychographic reconstruction.Comment: 8 pages, 8 figure
- …