Artificial Intelligence-Generated Terahertz Multi-Resonant Metasurfaces via Improved Transformer and CGAN Neural Networks

It is well known that the inverse design of terahertz (THz) multi-resonant graphene metasurfaces by using traditional deep neural networks (DNNs) has limited generalization ability. In this paper, we propose improved Transformer and conditional generative adversarial neural networks (CGAN) for the inverse design of graphene metasurfaces based upon THz multi-resonant absorption spectra. The improved Transformer can obtain higher accuracy and generalization performance in the StoV (Spectrum to Vector) design compared to traditional multilayer perceptron (MLP) neural networks, while the StoI (Spectrum to Image) design achieved through CGAN can provide more comprehensive information and higher accuracy than the StoV design obtained by MLP. Moreover, the improved CGAN can achieve the inverse design of graphene metasurface images directly from the desired multi-resonant absorption spectra. It is turned out that this work can finish facilitating the design process of artificial intelligence-generated metasurfaces (AIGM), and even provide a useful guide for developing complex THz metasurfaces based on 2D materials using generative neural networks

Self-tuning vibration absorber and the effect of its installation position on damping characteristics

A kind of self-tuning vibration absorber is presented. The relationship between the installation position and the vibration damping effect of the self-tuning vibration absorber is established, the influence on the damping effect is discussed. Then, on the vibration test bed, the theoretical analysis results are tested and verified. The results show that, installation position of the self-tuning vibration absorber has a significant influence on its vibration damping effect. When installed near the source location, the self-tuning vibration absorber has a better vibration damping effect. It is should be avoided in the area of vibration deterioration

An Improved Histogram Based Boosting Detection Rate Video Watermarking Algorithm

The existing histogram based video watermarking algorithm with temporal modulated is robust to combined attacks, but the watermark detection rate is not high due to watermark cannot embedded to the smoothness and still areas effectively. To increase the watermark detection rate, in this paper, we proposed the improved algorithm of shot segmentation first and then propose an improved video watermarking algorithm which firstly construct the watermark template in each frame video in the same shot through computing block based histogram and selecting the position of the relative high variance. Then we embed the watermark template into the video frame by temporal modulation without changing the destination of the shot group of the consecutive frames. The watermark sequence is extracted by comparing the correlation distribution of video frame and corresponding watermark template in the time domain. Experimental results demonstrate that the proposed algorithm is robust to recording attacks and guarantee the watermarking video quality at the same time, besides the watermark sequences can embedded to the smoothness and still areas effectively, and the watermark detection rate can increase by about 10% than previous methods

Effects of Six Common Dietary Nutrients on Murine Intestinal Organoid Growth

The intestinal epithelium of the gastrointestinal (GI) tract constantly renews itself to absorb nutrients and provide protection for the body from the outside world. Since the intestinal epithelium is constantly exposed to various chemicals and dietary components, it is critical to determine which constituents promote or inhibit intestinal epithelium health and growth rate. Intestinal organoids, three-dimensional miniature models of the intestines, represent an ex vivo tool to investigate intestinal physiology and growth patterns. In this study, we measured the growth rates of murine intestinal organoids exposed to various concentrations of different dietary constituents. Results indicate that caffeic acid inhibited organoid growth in a concentration-dependent manner, curcumin exhibited variable effectiveness, and vitamin C had no effect on organoid growth

Electromagnetic cloaking by layered structure of homogeneous isotropic materials

Electromagnetic invisibility cloak requires material with anisotropic distribution of the constitutive parameters deduced from a geometrical transformation as first proposed by Pendry et al. [Science 312, 1780 (2006)]. In this paper, we proposed a useful method to realize the required radius-dependent, anisotropic material parameters and to construct an electromagnetic cloak through concentric layered structure of thin, alternating layers of homogeneous isotropic materials. With proper design of the permittivity or the thickness ratio of the alternating layers, we demonstrated the low-reflection and power-flow bending properties of the proposed cloaking structure through rigorous analysis of the scattered electromagnetic fields. The proposed cloaking structure does not require anisotropy or inhomogeneity of the material constitutive parameters usually realized by metamaterials with subwavelength structured inclusions, therefore may lead to a practical path to an experimental demonstration of electromagnetic cloaking, especially in the optical range.Comment: 9 pages, 5 figure

Differential Impacts of Juvenile Hormone, Soldier Head Extract and Alternate Caste Phenotypes on Host and Symbiont Gene Expression in the Gut of the Termite Reticulitermes flavipes.

Background Termites are highly eusocial insects and show a division of labor whereby morphologically distinct individuals specialize in distinct tasks. In the lower termite Reticulitermes flavipes(Rhinotermitidae), non-reproducing individuals form the worker and soldier castes, which specialize in helping (e.g., brood care, cleaning, foraging) and defense behaviors, respectively. Workers are totipotent juveniles that can either undergo status quo molts or develop into soldiers or neotenic reproductives. This caste differentiation can be regulated by juvenile hormone (JH) and primer pheromones contained in soldier head extracts (SHE). Here we offered worker termites a cellulose diet treated with JH or SHE for 24-hr, or held them with live soldiers (LS) or live neotenic reproductives (LR). We then determined gene expression profiles of the host termite gut and protozoan symbionts concurrently using custom cDNA oligo-microarrays containing 10,990 individual ESTs. Results JH was the most influential treatment (501 total ESTs affected), followed by LS (24 ESTs), LR (12 ESTs) and SHE treatments (6 ESTs). The majority of JH up- and downregulated ESTs were of host and symbiont origin, respectively; in contrast, SHE, LR and LS treatments had more uniform impacts on host and symbiont gene expression. Repeat “follow-up” bioassays investigating combined JH + SHE impacts in relation to individual JH and SHE treatments on a subset of array-positive genes revealed (i) JH and SHE treatments had opposite impacts on gene expression and (ii) JH + SHE impacts on gene expression were generally intermediate between JH and SHE. Conclusions Our results show that JH impacts hundreds of termite and symbiont genes within 24-hr, strongly suggesting a role for the termite gut in JH-dependent caste determination. Additionally, differential impacts of SHE and LS treatments were observed that are in strong agreement with previous studies that specifically investigated soldier caste regulation. However, it is likely that gene expression outside the gut may be of equal or greater importance than gut gene expression

Mechanism of inflammatory cancer-associated fibroblast-mediated drug resistance in colorectal cancer cells

Background and purpose: Colorectal cancer (CRC) is one of the common malignancies, but the mechanism by which it develops resistance to drug remains unclear. The tumor microenvironment (TME), especially cancer-associated fibroblast (CAF), plays an important role in the occurrence, development and drug resistance of tumors. This study aimed to investigate the effect of inflammatory cancer-associated fibroblasts (iCAF) on drug resistance in CRC cells and its possible mechanism. Methods: The primary CAFs were collected from CRC patients underwent surgery in Putuo Hospital, Shanghai University of Traditional Chinese Medicine from Aug. 2022 to Sep. 2022, and the primary cells were sorted according to the surface marker of CAF[approved by the Ethics Committee of Putuo Hospital Affiliated to Shanghai University of Traditional Chinese Medicine: PTEC-A-2023-5(S)-1], platelet derived growth factor receptor alpha (PDGFRA), to screen iCAF. Human intestinal fibroblast (HIF) and iCAF cells were cultured using serum-free medium to obtain conditioned medium. According to the treatment method, colon cancer cells were divided into control group (no treatment), experimental group 1(treated with HIF-CM) and experimental group 2 (treated with iCAF-CM). We observed the changes in the survival rate and apoptotic rate of CRC cells, the changes in protein and mRNA levels and the effect on the Wnt/β-catenin signaling pathway after stimulation with HIF-CM or iCAF-CM. Results: After iCAFs stimulation, the half inhibition concentration (IC50) of CRC cells was higher compared with the control group and HIF-CM group (P<0.05). Compared with the control group and HIF-CM group, the apoptotic rate of tumor cells in iCAF-CM group decreased significantly, the expression of caspase-3 was decreased, and the expressions of Bcl-2, Bcl-xL and survivin were increased (P<0.05). The Wnt/β-catenin signaling pathway was activated in the iCAF-CM group. Conclusion: iCAFs can mediate drug resistance in CRC cells, and the mechanism is related to the activation of Wnt/β-catenin signaling pathway