6,052 research outputs found
A note on the connection between nonextensive entropy and -derivative
In order to study as a whole the major part of entropy measures, we introduce
a two-parameter non-extensive entropic form with respect to the
\textit{h}-derivative which generalizes the conventional Newton-Leibniz
calculus. This new entropy, , is proved to describe the non-extensive
systems and recover several types of the well-known non-extensive entropic
expressions, such as the Tsallis entropy, the Abe entropy, the Shafee entropy,
the Kaniadakis entropy and even the classical Boltzmann\,--\,Gibbs one. As a
generalized entropy, its corresponding properties are also analyzed.Comment: 6 pages, 1 figur
A New Golden Age of Natural Products Drug Discovery
The 2015 Nobel Prize in Physiology or Medicine has been awarded to William C. Campbell, Satoshi Omura, and Youyou Tu for the discovery of avermectins and artemisinin, respectively, therapies that revolutionized the treatment of devastating parasite diseases. With the recent technological advances, a New Golden Age of natural products drug discovery is dawning
Natural products by synthetic biology and microbial engineering
Natural products are made from simple building blocks, the structural diversity found in natural products is the result of Nature’s intrinsic use of combinatorial biosynthesis, and recent progress in microbial genomics and synthetic biology has sparked the emergence of a suite of contemporary approaches to natural products by microbial engineering and fermentation. Current strategies are mainly based on the collective knowledge of genetics, microbiology, evolution, enzymology, and structural biology that governs the natural product biosynthetic machinery. While successful, they are limited by what information is gleaned from the above disciplines and how that information can be applied to construct the designer pathways. Nature has used evolution over billions of years to become an expert in combinatorial biosynthesis and microbial engineering, and we have only begun to tap into this knowledge. Selected examples from our current researches will be presented to highlight the opportunities in accessing natural products and expanding natural product structural diversity by exploring the vast combinatorial biosynthesis repertoire found in Nature
An ILP Solver for Multi-label MRFs with Connectivity Constraints
Integer Linear Programming (ILP) formulations of Markov random fields (MRFs)
models with global connectivity priors were investigated previously in computer
vision, e.g., \cite{globalinter,globalconn}. In these works, only Linear
Programing (LP) relaxations \cite{globalinter,globalconn} or simplified
versions \cite{graphcutbase} of the problem were solved. This paper
investigates the ILP of multi-label MRF with exact connectivity priors via a
branch-and-cut method, which provably finds globally optimal solutions. The
method enforces connectivity priors iteratively by a cutting plane method, and
provides feasible solutions with a guarantee on sub-optimality even if we
terminate it earlier. The proposed ILP can be applied as a post-processing
method on top of any existing multi-label segmentation approach. As it provides
globally optimal solution, it can be used off-line to generate ground-truth
labeling, which serves as quality check for any fast on-line algorithm.
Furthermore, it can be used to generate ground-truth proposals for weakly
supervised segmentation. We demonstrate the power and usefulness of our model
by several experiments on the BSDS500 and PASCAL image dataset, as well as on
medical images with trained probability maps.Comment: 19 page
Deforming black holes with even multipolar differential rotation boundary
Motivated by the novel asymptotically global AdS solutions with deforming
horizon in [JHEP {\bf 1802}, 060 (2018)], we analyze the boundary metric with
even multipolar differential rotation and numerically construct a family of
deforming solutions with quadrupolar differential rotation boundary, including
two classes of solutions: solitons and black holes. In contrast to solutions
with dipolar differential rotation boundary, we find that even though the norm
of Killing vector becomes spacelike for certain regions of polar
angle when , solitons and black holes with quadrupolar
differential rotation still exist and do not develop hair due to superradiance.
Moreover, at the same temperature, the horizonal deformation of quadrupolar
rotation is smaller than that of dipolar rotation. Furthermore, we also study
the entropy and quasinormal modes of the solutions, which have the analogous
properties to that of dipolar rotation.Comment: 18 pages, 21 figure
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