60 research outputs found
A New Multistage Medical Segmentation Method Based on Superpixel and Fuzzy Clustering
The medical image segmentation is the key approach of image processing for brain MRI images. However, due to the visual complex appearance of image structures and the imaging characteristic, it is still challenging to automatically segment brain MRI image. A new multi-stage segmentation method based on superpixel and fuzzy clustering (MSFCM) is proposed to achieve the good brain MRI segmentation results. The MSFCM utilizes the superpixels as the clustering objects instead of pixels, and it can increase the clustering granularity and overcome the influence of noise and bias effectively. In the first stage, the MRI image is parsed into several atomic areas, namely, superpixels, and a further parsing step is adopted for the areas with bigger gray variance over setting threshold. Subsequently, designed fuzzy clustering is carried out to the fuzzy membership of each superpixel, and an iterative broadcast method based on the Butterworth function is used to redefine their classifications. Finally, the segmented image is achieved by merging the superpixels which have the same classification label. The simulated brain database from BrainWeb site is used in the experiments, and the experimental results demonstrate that MSFCM method outperforms the traditional FCM algorithm in terms of segmentation accuracy and stability for MRI image
Topological edge and corner states in Bi fractals on InSb
Topological materials hosting metallic edges characterized by integer
quantized conductivity in an insulating bulk have revolutionized our
understanding of transport in matter. The topological protection of these edge
states is based on symmetries and dimensionality. However, only
integer-dimensional models have been classified, and the interplay of topology
and fractals, which may have a non-integer dimension, remained largely
unexplored. Quantum fractals have recently been engineered in metamaterials,
but up to present no topological states were unveiled in fractals realized in
real materials. Here, we show theoretically and experimentally that topological
edge and corner modes arise in fractals formed upon depositing thin layers of
bismuth on an indium antimonide substrate. Scanning tunneling microscopy
reveals the appearance of (nearly) zero-energy modes at the corners of
Sierpi\'nski triangles, as well as the formation of outer and inner edge modes
at higher energies. Unexpectedly, a robust and sharp depleted mode appears at
the outer and inner edges of the samples at negative bias voltages. The
experimental findings are corroborated by theoretical calculations in the
framework of a continuum muffin-tin and a lattice tight-binding model. The
stability of the topological features to the introduction of a Rashba
spin-orbit coupling and disorder is discussed. This work opens the perspective
to novel electronics in real materials at non-integer dimensions with robust
and protected topological states.Comment: Main manuscript 14 pages, supplementary material 34 page
Comprehensive targeted super-deep next generation sequencing enhances differential diagnosis of solitary pulmonary nodules
A Study on the Production Process Control of Zanthoxylum bungeanum Maxim Seed Kernel Oil without Trans-Fatty Acids
The process control of the production of Zanthoxylum bungeanum Maxim seed kernel oil (ZSKO) with no trans-fatty acids (TFAs) was investigated. Results revealed that drying temperature and time had a small effect on TFA formation in ZSKO. And high concentrations of sodium hydroxide solution had some effect on TFA formation in ZKSO, but there were no TFAs when the concentration of the sodium hydroxide solution was lower than 20% and even at boiling temperature for one hour. The roasting temperature and duration for Zanthoxylum bungeanum Maxim seed (ZS) should be properly controlled at 100°C for six hours or 150°C for two hours. ZS, which has a moisture content of 18%, was pressed four times (two hours) at less than 60°C, and ZSKO was obtained by collection through centrifuge separation. This contained 90.84% unsaturated fatty acids, which mainly include 32.49%  α-linolenic acid, 29.88% linoleic acid, and 27.52% oleic acids; and there was no TFA. Its acidic value and peroxide value conformed to China standards for edible oil. Therefore, ZKSO could be used as a healthy food for further development
M2M Security Technology of CPS Based on Blockchains
As the core of intelligent manufacturing, cyber-physical systems (CPS) have serious security issues, especially for the communication security of their terminal machine-to-machine (M2M) communications. In this paper, blockchain technology is introduced to address such a security problem of communications between different types of machines in the CPS. According to the principles of blockchain technology, we designed a blockchain for secure M2M communications. As a communication system, M2M consists of public network areas, device areas, and private areas, and we designed a sophisticated blockchain structure between the public area and private area. For validating our design, we took cotton spinning production as a case study to demonstrate our solution to M2M communication problems under the CPS framework. We have demonstrated that the blockchain technology can effectively solve the safety of expansion of machines in the production process and the communication data between the machines cannot be tampered with
A Study on the Production Process Control of Zanthoxylum bungeanum Maxim Seed Kernel Oil without Trans-Fatty Acids
The process control of the production of Zanthoxylum bungeanum Maxim seed kernel oil (ZSKO) with no trans-fatty acids (TFAs) was investigated. Results revealed that drying temperature and time had a small effect on TFA formation in ZSKO. And high concentrations of sodium hydroxide solution had some effect on TFA formation in ZKSO, but there were no TFAs when the concentration of the sodium hydroxide solution was lower than 20% and even at boiling temperature for one hour. The roasting temperature and duration for Zanthoxylum bungeanum Maxim seed (ZS) should be properly controlled at 100 ∘ C for six hours or 150 ∘ C for two hours. ZS, which has a moisture content of 18%, was pressed four times (two hours) at less than 60 ∘ C, and ZSKO was obtained by collection through centrifuge separation. This contained 90.84% unsaturated fatty acids, which mainly include 32.49% -linolenic acid, 29.88% linoleic acid, and 27.52% oleic acids; and there was no TFA. Its acidic value and peroxide value conformed to China standards for edible oil. Therefore, ZKSO could be used as a healthy food for further development
Construction of Polyelectrolyte-Responsive Microgels, and Polyelectrolyte Concentration and Chain Length-Dependent Adsorption Kinetics
We report on the construction of a polyelectrolyte-responsive system
evolved from sterically stabilized protonated polyÂ(2-vinylpyridine)
(P2VPH<sup>+</sup>) microgels. Negatively charged sodium dodecylbenzenesulfonate
(SDBS) surfactants could be readily internalized into the cationic
microgels by means of electrostatic interactions, resulting in microgel
collapse and concomitant formation of surfactant micellar domains
(P2VPH<sup>+</sup>/SDBS)-contained electrostatic complexes. These
internal hydrophobic domains conferred the opportunity of fluorescent
dyes to be loaded. The obtained fluorescent microgel complexes could
be further disintegrated in the presence of anionic polyelectrolyte,
polyÂ(sodium 4-styrenesulfonate) (PNaStS). The stronger electrostatic
attraction between multivalent P2VPH<sup>+</sup> microgels and PNaStS
polyelectrolyte than single-charged surfactant led to triggered release
of the encapsulated pyrene dyes from the hydrophobic interiors into
microgel dispersion. The process was confirmed by laser light scattering
(LLS) and fluorescence measurements. Furthermore, the entire dynamic
process of PNaStS adsorption into P2VPH<sup>+</sup> microgel interior
was further studied by stopped-flow equipment as a function of polyelectrolyte
concentration and degree of polymerization. The whole adsorption process
could be well fitted with a double-exponential function, suggesting
a fast (Ï„<sub>1</sub>) and a slow (Ï„<sub>2</sub>) relaxation
time, respectively. The fast process (Ï„<sub>1</sub>) was correlated
well with the approaching of PNaStS with P2VPH<sup>+</sup> microgel
to form a nonequilibrium complex within the microgel shell, while
the slow process (Ï„<sub>2</sub>) was consistent with the formation
of equilibrium complexes in the microgel deeper inside. This simple
yet feasible design augurs well for the promising applications in
controlled release fields
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