A Hyper-Chaotically Encrypted Robust Digital Image Watermarking Method with Large Capacity Using Compress Sensing on a Hybrid Domain.

The digital watermarking technique is a quite promising technique for both image copyright protection and secure transmission. However, many existing techniques are not as one might have expected for robustness and capacity simultaneously. In this paper, we propose a robust semi-blind image watermarking scheme with a high capacity. Firstly, we perform a discrete wavelet transformation (DWT) transformation on the carrier image. Then, the watermark images are compressed via a compressive sampling technique for saving storage space. Thirdly, a Combination of One and Two-Dimensional Chaotic Map based on the Tent and Logistic map (TL-COTDCM) is used to scramble the compressed watermark image with high security and dramatically reduce the false positive problem (FPP). Finally, a singular value decomposition (SVD) component is used to embed into the decomposed carrier image to finish the embedding process. With this scheme, eight 256×256 grayscale watermark images are perfectly embedded into a 512×512 carrier image, the capacity of which is eight times over that of the existing watermark techniques on average. The scheme has been tested through several common attacks on high strength, and the experiment results show the superiority of our method via the two most used evaluation indicators, normalized correlation coefficient (NCC) values and the peak signal-to-noise ratio (PSNR). Our method outperforms the state-of-the-art in the aspects of robustness, security, and capacity of digital watermarking, which exhibits great potential in multimedia application in the immediate future.

The acetylation modification regulates the stability of Bm30K-15 protein and its mechanism in silkworm, Bombyx mori.

The 30 K proteins are the major silkworm hemolymph proteins and are involved in a variety of physiological processes, such as nutrient and energy storage, embryogenesis, immune response, and inhibition of apoptosis. The Bm30K-15 protein is one of the 30 K proteins and is abundant in the hemolymph of fifth instar silkworm larva. We previously found that the Bm30K-15 protein can be acetylated. In the present study, we found that acetylation can improve the protein stability of Bm30K-15. Further exploration confirmed that the increase in protein stability by acetylation was caused by competition between acetylation and ubiquitination. In summary, these findings aim to provide insight into the effect of acetylation modification on the protein level and stability of the Bm30K-15 and the possible molecular mechanism of its existence in silkworm, Bombyx mori.

Unraveling the Synergistic Catalytic Effects of TiO2 and Pr6O11 on Superior Dehydrogenation Performances of α-AlH3.

The pivotal steps for the practical application of dehydrogenation of aluminum hydride (AlH3) have been to decrease the temperature and increase the content of AlH3. Herein, the initial dehydrogenation temperature of AlH3 decreased to 43 °C with the amount of released hydrogen of 8.3 wt % via introducing TiO2 and Pr6O11 with synergistic catalysis effects, and its apparent activation energy of the dehydrogenation reaction decreased to 56.1 kJ mol-1, which is 52% lower than that of pure AlH3. These differences in performances of the samples are further evaluated by determining the electron density of Al-H bonds during dehydrogenation. The multiple valence state conversions of TiO2 and Pr6O11 promoted the electron transfer of H in AlH3, and a novel dehydrogenation pathway of PrH2.37 formed simultaneously, which could accelerate the breakage of Al-H bonds. The density functional theory calculations further exhibit that there are fewer electrons around H in AlH3 and the Al-H bond energy is weaker at the atomic levels, which is more conducive to the release of hydrogen. A higher hydrogen storage capacity and a lower dehydrogenation temperature make AlH3 one of the most promising hydrogen source media for mobile applications.

Large-scale isolation and antitumor mechanism evaluation of compounds from the traditional Chinese medicine Cordyceps Militaris.

We established a large-scale separation and purification platform to obtain kilogram amounts of natural compounds from the extraction of the fruiting bodies of C. militaris. Seven monomeric compounds, N6-(2-hydroxyethyl) adenosine (HEA), ergosterol (E), ergosta-7,22-diene-3,5,6-triol (EI), 5α,8α-epidioxy-(22E,24R)-ergosta-6,22-dien-3ß-ol (ED),ergosta-7,22-dien-3ß,5α-dihydroxy-6-one (EO), (20S,22E,24R)-Eegosta-7,22-dien-3ß,5α,6ß,9α-tetraol (ET), and (24S)-5,22-stigmastadien-3ß-ol (SE), were harvested using different solvents, and the structure of each compound was identified. The activities and functions of the isolated compounds were tested by label-free, real-time cell analysis methods at the cellular level, and their antitumor effects were verified using mouse models of Lewis and H22 tumors. The anti-insomnia effect of HEA was tested in an anti-insomnia mouse model. The interactions between E and 8 A549 cell proteins were determined. The biosynthetic pathways of HEA and E, which possess pharmacologically active monomers, were determined. This platform can provide a theoretical basis for the further development and discovery of novel natural medicines.

A Novel Image-Encryption Scheme Based on a Non-Linear Cross-Coupled Hyperchaotic System with the Dynamic Correlation of Plaintext Pixels.

Based on a logistic map and Feigenbaum map, we proposed a logistic Feigenbaum non-linear cross-coupled hyperchaotic map (LF-NCHM) model. Experimental verification showed that the system is a hyperchaotic system. Compared with the existing cross-coupled mapping, LF-NCHM demonstrated a wider hyperchaotic range, better ergodicity and richer dynamic behavior. A hyperchaotic sequence with the same number of image pixels was generated by LF-NCHM, and a novel image-encryption algorithm with permutation that is dynamically related to plaintext pixels was proposed. In the scrambling stage, the position of the first scrambled pixel was related to the sum of the plaintext pixel values, and the positions of the remaining scrambled pixels were related to the pixel values after the previous scrambling. The scrambling operation also had a certain diffusion effect. In the diffusion phase, using the same chaotic sequence as in the scrambling stage increased the usage rate of the hyperchaotic sequence and improved the calculation efficiency of the algorithm. A large number of experimental simulations and cryptanalyses were performed, and the results proved that the algorithm had outstanding security and extremely high encryption efficiency. In addition, LF-NCHM could effectively resist statistical analysis attacks, differential attacks and chosen-plaintext attacks.

Identification and Investigation of miRNAs From Gastrodia elata Blume and Their Potential Function.

Gastrodia elata Blume (G. elata) is a valuable traditional Chinese medicine with neuroprotection, anti-inflammatory, and immune regulatory functions. MicroRNAs (miRNA) is a kind of endogenous noncoding small RNAs that plays distinctly important roles for gene regulation of organisms. So far, the research on G. elata is mainly focused on the pharmacological functions of the natural chemical ingredients, and the function of G. elata miRNA remains unknown. In this study, 5,718 known miRNAs and 38 novel miRNAs were identified by high-throughput sequencing from G. elata. Based on GO and KEGG analysis, we found that the human genes possibly regulated by G. elata miRNAs were related to the cell cycle, immune regulation, intercellular communication, etc. Furthermore, two novel miRNAs as Gas-miR01 and Gas-miR02 have stable and high expression in the medicinal tissues of G. elata. Further bioinformatics prediction showed that both Gas-miR01 and Gas-miR02 could target Homo sapiens A20 gene, furthermore, the dual-luciferase reporter gene assay and Western Blotting verified the interaction of Gas-miR01 or Gas-miR02 with A20. These evidences suggested that G. elata-unique miRNAs might be involved in certain physiological processes. The animal experiment showed that Gas-miR01 and Gas-miR02 could be detected in some tissues of mice by intragastric administration; meanwhile, the A20 expression in some tissues of mice was downregulated. These results supported for the functional study of G. elata miRNAs.

A Novel Delay Linear Coupling Logistics Map Model for Color Image Encryption.

With the popularity of the Internet, the transmission of images has become more frequent. It is of great significance to study efficient and secure image encryption algorithms. Based on traditional Logistic maps and consideration of delay, we propose a new one-dimensional (1D) delay and linearly coupled Logistic chaotic map (DLCL) in this paper. Time delay is a common phenomenon in various complex systems in nature, and it will greatly change the dynamic characteristics of the system. The map is analyzed in terms of trajectory, Lyapunov exponent (LE) and Permutation entropy (PE). The results show that this map has wide chaotic range, better ergodicity and larger maximum LE in comparison with some existing chaotic maps. A new method of color image encryption is put forward based on DLCL. In proposed encryption algorithm, after various analysis, it has good encryption performance, and the key used for scrambling is related to the original image. It is illustrated by simulation results that the ciphered images have good pseudo randomness through our method. The proposed encryption algorithm has large key space and can effectively resist differential attack and chosen plaintext attack.

Design of conformal lens by drilling holes materials using quasi-conformal transformation optics.

In this paper, based on quasi-conformal transformation optics, a 3D conformal lens made of isotropic and non-resonant metamaterial is designed, which can make a cylindrical conformal array behave similarly to a uniform linear array. After discussion and simplification in the two-dimensional model, we realize the proposed lens by utilizing drilling-hole material in the three-dimensional structure. The ring-like shape and forward-only radiation make it possible to equip the lens on a cylindrical device.