Yang Yang

Bio: Yang Yang is an academic researcher from Chinese Academy of Sciences. The author has contributed to research in topics: Medicine & Computer science. The author has an hindex of 171, co-authored 2644 publications receiving 153049 citations. Previous affiliations of Yang Yang include Zhejiang University & Northwest Normal University.

A ROI-based high capacity reversible data hiding scheme with contrast enhancement for medical images

Abstract: In this paper, we attempt to investigate the secure archiving of medical images which are stored on semi-trusted cloud servers, and focus on addressing the complicated and challenging integrity control and privacy preservation issues. With the intention of protecting the medical images stored on a semi-trusted server, a novel ROI-based high capacity reversible data hiding (RDH) scheme with contrast enhancement is proposed in this paper. The proposed method aims at improving the quality of the medical images effectively and embedding high capacity data reversibly meanwhile. Therefore, the proposed method adopts “adaptive threshold detector” (ATD) segmentation algorithm to automatically separate the “region of interest” (ROI) and “region of non-interest” (NROI) at first, then enhances the contrast of the ROI region by stretching the grayscale and embeds the data into peak bins of the stretched histogram without extending the histogram bins. Lastly, the rest of the required large of data are embedded into NROI region regardless its quality. In addition, the proposed method records the edge location of the segmentation instead of recording the location of the overflow and underflow. The experiment shows that the proposed method can improve the quality of medical images obviously whatever in low embedding rate or high embedding rate when compared with other contrast-based RDH methods.

Dual Graphitic-N Doping in a Six-Membered C-Ring of Graphene-Analogous Particles Enables an Efficient Electrocatalyst for the Hydrogen Evolution Reaction.

Abstract: Graphene-based materials still exhibit poor electrocatalytic activities for the hydrogen evolution reaction (HER) although they are considered to be the most promising electrocatalysts. We fabricated a graphene-analogous material displaying exceptional activity towards the HER under acidic conditions with an overpotential (57 mV at 10 mA cm-2 ) and Tafel slope (44.6 mV dec-1 ) superior to previously reported graphene-based materials, and even comparable to the state-of-the art Pt/C catalyst. X-ray absorption near-edge structure (XANES) and solid-state NMR studies reveal that the distinct feature of its structure is dual graphitic-N doping in a six-membered carbon ring. Density functional theory (DFT) calculations show that the unique doped structure is beneficial for the activation of C-H bonds and to make the carbon atom bonded to two graphitic N atoms an active site for the HER.

Significantly accelerated PEC degradation of organic pollutant with addition of sulfite and mechanism study

Abstract: Visible-light-driven photoelectrochemical (PEC) catalysis has been widely studied as a promising technique for the degradation of organic pollutants in wastewater. Herein, we report a sulfite-enhanced PEC degradation process for the degradation of organic pollutant. The degradation rate was significantly enhanced by ～30 times with the addition of 16 mM sulfite. The Electron Spin Resonance (ESR), Transient Absorption (TA) and hole scavenger studies showed that sulfite radicals ( S O 3 ⦁ - ) were the main reactive species in the reactions. The pollutant degradation pathway was studied by in-situ techniques and mass spectrometer, showing that the sulfite addition can promote the cleavage of aromatic ring C C bond and C N bond.

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

Fast parallel algorithms for short-range molecular dynamics

Abstract: Three parallel algorithms for classical molecular dynamics are presented. The first assigns each processor a fixed subset of atoms; the second assigns each a fixed subset of inter-atomic forces to compute; the third assigns each a fixed spatial region. The algorithms are suitable for molecular dynamics models which can be difficult to parallelize efficiently—those with short-range forces where the neighbors of each atom change rapidly. They can be implemented on any distributed-memory parallel machine which allows for message-passing of data between independently executing processors. The algorithms are tested on a standard Lennard-Jones benchmark problem for system sizes ranging from 500 to 100,000,000 atoms on several parallel supercomputers--the nCUBE 2, Intel iPSC/860 and Paragon, and Cray T3D. Comparing the results to the fastest reported vectorized Cray Y-MP and C90 algorithm shows that the current generation of parallel machines is competitive with conventional vector supercomputers even for small problems. For large problems, the spatial algorithm achieves parallel efficiencies of 90% and a 1840-node Intel Paragon performs up to 165 faster than a single Cray C9O processor. Trade-offs between the three algorithms and guidelines for adapting them to more complex molecular dynamics simulations are also discussed.

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

Electronics and optoelectronics of two-dimensional transition metal dichalcogenides.

Abstract: Single-layer metal dichalcogenides are two-dimensional semiconductors that present strong potential for electronic and sensing applications complementary to that of graphene.