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Pentaquark states with the configuration in a simple model
We discuss the mass splittings for the -wave triply heavy pentaquark
states with the configuration which is a mirror
structure of . The latter configuration is related with the nature
of observed by the LHCb Collaboration. The considered pentaquark
masses are roughly estimated with a simple method. One finds that such states
are probably not narrow even if they do exist. This leaves room for molecule
interpretation for a state around the low-lying threshold of a doubly heavy
baryon and a heavy-light meson, e.g. , if it were observed. As a by
product, we conjecture that upper limits for the masses of the conventional
triply heavy baryons can be determined by the masses of the conventional doubly
heavy baryons.Comment: 19 pages, 1 figure, 10 tables; Version accepted by Eur. Phys. J.
A Survey of Methods for Estimating Hurst Exponent of Time Sequence
The Hurst exponent is a significant indicator for characterizing the
self-similarity and long-term memory properties of time sequences. It has wide
applications in physics, technologies, engineering, mathematics, statistics,
economics, psychology and so on. Currently, available methods for estimating
the Hurst exponent of time sequences can be divided into different categories:
time-domain methods and spectrum-domain methods based on the representation of
time sequence, linear regression methods and Bayesian methods based on
parameter estimation methods. Although various methods are discussed in
literature, there are still some deficiencies: the descriptions of the
estimation algorithms are just mathematics-oriented and the pseudo-codes are
missing; the effectiveness and accuracy of the estimation algorithms are not
clear; the classification of estimation methods is not considered and there is
a lack of guidance for selecting the estimation methods. In this work, the
emphasis is put on thirteen dominant methods for estimating the Hurst exponent.
For the purpose of decreasing the difficulty of implementing the estimation
methods with computer programs, the mathematical principles are discussed
briefly and the pseudo-codes of algorithms are presented with necessary
details. It is expected that the survey could help the researchers to select,
implement and apply the estimation algorithms of interest in practical
situations in an easy way.Comment: 46 pages, 8 figures, 4 tables, 24 algorithms with pseudo-code
Efficient hydrolysis of raw starch and ethanol fermentation: a novel raw starch-digesting glucoamylase from Penicillium oxalicum
Additional file 3: Figure S2. SDS-PAGE analysis of the recombinant rPoGA15A and native PoGA15A. Lane 1, protein molecular weight marker; lane 2, the purified recombinant rPoGA15A; lane 3, the native PoGA15A
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