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Learning the knowledge hidden in the manifold-geometric distribution of the dataset is essential for many machine learning algorithms. However, geometric distribution is usually corrupted by noise, especially in the high-dimensional dataset. In this paper, we propose a denoising method to capture the "true" geometric structure of a high-dimensional nonrigid point cloud dataset by a variational approach. Firstly, we improve the Tikhonov model by adding a local structure term to make variational diffusion on the tangent space of the manifold. Then, we define the discrete Laplacian operator by graph theory and get an optimal solution by the Euler–Lagrange equation. Experiments show that our method could remove noise effectively on both synthetic scatter point cloud dataset and real image dataset. Furthermore, as a preprocessing step, our method could improve the robustness of manifold learning and increase the accuracy rate in the classification problem. [ABSTRACT FROM AUTHOR]

Au@Cu2O core-shell nanorods with tunable thickness of Cu2O shell were synthesized and their linear and nonlinear optical responses were investigated. Two transverse plasmon resonance peaks were observed when the Au nanorods were coated with Cu2O shells, which were adjusted by the Cu2O shell thickness. The nonlinear absorption of the Au@Cu2O nanorods is enhanced by 5 times at the longitudinal plasmon resonance wavelength compared with that of bare Au nanorods. More intriguingly, largely enhanced nonlinear refraction and suppressed nonlinear absorption at the transverse plasmon resonance wavelength were observed in the Au@Cu2O nanorods. Our findings indicate the existence of strong local field enhancement at the interface between the Au core and the Cu2O shell, which would provide a promising strategy in designing plasmonic nonlinear nanodevices with good nonlinear figures of merit. [ABSTRACT FROM AUTHOR]

Abstract: In recent years, optical properties of the complex systems involving both metal plasmons and molecular/semiconductor excitons have attracted great attentions due to their rich and varied optical characteristics. In this type of hybrid systems, the plasmon plays a role to drastically enhance the coupling between the system and external field, while the exciton plays a role to control the detailed spectral properties, providing tempting avenues for manipulating new optical control beyond what can be achieved using either of the components. In addition to the mutual coupling between the plasmon and exciton, their different linewidths and the abilities to couple with external field provide a variety of control handles to tune the optical properties of the hybrid systems. It thus allows to precisely manipulate light on the nanometer‐scale, opening up opportunities for novel sensing, light‐emitting, and photovoltaic devices. Here, the recent progress in both theoretical and experimental developments is reviewed. The theoretical part is focused on studies of the absorption/scattering spectral line shapes of the hybrid systems, especially the transition between Fano resonance and Rabi splitting peaks. The various technical approaches to tune the plasmon–exciton coupling in complex systems are reviewed in the experimental part. [ABSTRACT FROM AUTHOR]

Based on the theory of one-dimensional separate soliton pairs formed in a serial photorefractive crystal circuit, the effects of the dark soliton on the self-deflection of the bright one in one separate bright-dark soliton pair are investigated by taking the diffusion term into account. The numerical results obtained by solving the nonlinear propagation equation show that the bright soliton moves on a parabolic trajectory in the crystal and its spatial shift changes with the input intensity of the dark soliton. These effects are further studied using perturbation analysis and the characteristics of the spatial shift of the bright soliton varying with the input maximum intensity of the dark soltion are analysed. The position of the bright soliton at the output surface of the crystal can be determined accurately according to the formula obtained from perturbation method. [ABSTRACT FROM AUTHOR]

The self-deflection of a solitary wave arising from diffusion effects in a biased photovoltaic photorefractive crystal has been systematically investigated by employing numerical techniques. Adjusting both strength and polarity of the biased field can change the bending angle of the screening-photovoltaic (SP) soliton, and it is more effective by adjusting the polarity than by adjusting the strength. The stronger the input intensity is, the larger the bending angle is for a dark SP soliton, whereas the bending angle tends to decrease for very weak input intensity as well as for a very strong one, and has a larger value between these two regimes for a bright SP soliton. The dark SP soliton deflects left, whereas the bright one deflects right. The self-bending process of a SP soliton still occurs in a lossy crystal. If the input optical beam is a Gauss beam, whether it can evolve into a stable SP bright soliton or not in the crystal, it will bend with distance. [ABSTRACT FROM AUTHOR]

AbstractMastitis in cows is caused by the inflammation of the mammary glands due to an infection by external pathogenic bacteria. Mammary gland epithelial cells, which are in direct contact with the external environment, are responsible for the first line of defense of the mammary gland against pathogenic bacteria, playing an essential role in immune defense. To investigate the mechanism of bovine mammary epithelial cells in the inflammatory process, we treated the cells with LPS for 12 hours and analyzed the changes in mRNA by transcriptome sequencing. The results showed that compared to the control group, the LPS treatment group had 121 up-regulated genes and 18 down-regulated genes. GO and KEGG enrichment analysis revealed that these differential genes were mainly enriched in the IL-17 signaling pathway, Legionellosis, Cytokine-cytokine receptor interaction, NF-kappa B signaling pathway, and other signaling pathways. Furthermore, the expression of GRO1 and CXCL3 mRNAs increased significantly after LPS treatment. These findings provide new insights for the treatment of mastitis in cows in the future. [ABSTRACT FROM AUTHOR]

Mastitis in cows is caused by the inflammation of the mammary glands due to an infection by external pathogenic bacteria. Mammary gland epithelial cells, which are in direct contact with the external environment, are responsible for the first line of defense of the mammary gland against pathogenic bacteria, playing an essential role in immune defense. To investigate the mechanism of bovine mammary epithelial cells in the inflammatory process, we treated the cells with LPS for 12 hours and analyzed the changes in mRNA by transcriptome sequencing. The results showed that compared to the control group, the LPS treatment group had 121 up-regulated genes and 18 down-regulated genes. GO and KEGG enrichment analysis revealed that these differential genes were mainly enriched in the IL-17 signaling pathway, Legionellosis, Cytokine-cytokine receptor interaction, NF-kappa B signaling pathway, and other signaling pathways. Furthermore, the expression of GRO1 and CXCL3 mRNAs increased significantly after LPS treatment. These findings provide new insights for the treatment of mastitis in cows in the future.

Dual plasmonic Au@Cu 2-x S core-shell nanorods (NRs) have been fabricated by using a hydrothermal method and plasmon-coupled effect between the Au core and Cu 2-x S shell in the near-infrared (NIR) region. The extinction spectrum of Au@Cu 2-x S NRs is dominated by the surface plasmon resonance (SPR) of the Cu 2-x S shell, the transverse surface plasmon resonance (TSPR), and the longitudinal surface plasmon resonance (LSPR) of the Au NRs. With the Cu 2-x S shell increasing (fixed Au NRs), the TSPR peak slightly redshifts and the LSPR and SPR peaks blueshift, owing to competition between the redshift of the refractive index effect and blueshift from the plasmon coupled effect. Although, for Au@Cu 2 S NRs, only TSPR and LSPR peaks can be seen and a redshift arises with the increasing Cu 2 S shell thickness, implying that no plasmonic coupling between Au NRs and Cu 2 S shell occurred. The extinction spectrum of the Au@Cu 2-x S NRs with three coupled resonance peaks is simulated by using the FDTD method, taking into account the electron-transfer effect. The dispersion properties of the coupling of Au@Cu 2-x S NRs with the LSPR of the initial Au core are studied experimentally by changing the length of the Au NRs, which are explained theoretically by the coupled harmonic oscillator model. The calculated coupled coefficients between SPR of the Cu 2-x S shell and LSPR of the Au NRs is 180 meV, which is much stronger than that of TSPR of Au NRs of 55 meV. Finally, the enhanced photothermal effect of Au@Cu 2-x S NRs has been demonstrated., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

This paper presents calculations for an idea in photorefractive spatial soliton, namely, screening solitons form in a biased series photorefractive crystal circuit consisting of two photorefractive crystals connected electronically by electrode leads in a chain with a voltage source. A system of two coupled equations is derived under appropriate conditions for two-beam propagation in the crystal circuit. The possibility of obtaining steady-state bright and dark screening soliton solutions is investigated in one dimension and, the existence of dark-dark, bright-dark, and bright-bright separate screening soliton pairs in such a circuit is proved. The numerical results show that the two solitons in a soliton pair can affect each other by the light-induced current and their coupling can affect their spatial profiles, dynamical evolutions, stabilities, and self-deflection. Under the limit in which the optical wave has a spatial extent much less than the width of the crystal, only the dark soliton can affect the other soliton by the light-induced current, but the bright soliton cannot. For a bright-dark or dark-dark soliton pair, the dark soliton in a weak input intensity can be obtained for a larger nonlinearity than for a stronger input intensity. For a bright-dark soliton pair, increasing the input intensity of the dark soliton can increase the bending angle of the bright soliton. Some potential applications are discussed.