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To realise wide-band stealth of radar absorbing material, a special-shaped honeycomb radar absorbing structure within nested cone-shaped scattering configuration is designed. Based on the HS theory and the impedance matching design, the rule about the influence of the geometry parameter and electromagnetic parameter on the absorbing performance is analysed. In addition, the reflectivity performance is analysed on the condition of oblique incidence angles. By optimising the geometry parameters of the special-shaped honeycomb structure and designing the multilayer composite structure based on impedance matching theory, the results indicate that the two absorbing peaks can be formed for the special-shaped honeycomb radar absorbing structure, and the reflectivity is improved for both the vertical and oblique incidence angles.

Aiming at the large-scale application of metasurface in the field of radar stealth, we present a hybrid resonance-based and dispersion substrate integrated checkerboard metasurface (CMS) for reducing the radar cross section (RCS) of flat metallic targets. Considering the frequency-dependent characteristics of such a dispersion material, a pair of single and dual resonant artificial magnetic conductor meta-atoms with the modified "crusades-like" cell topologies is employed to maximize the operating bandwidth; besides, a comprehensive and thorough investigation on the resonance mechanism is conducted in this paper to provide an intuitive physical insight of meta-atoms' reflection responses. By comparing the predicted results with simulations, the quasi-periodic effect is introduced to explain the frequency shift of 10 dB RCS reduction bandwidth. In the implementation procedure, a prototype of the designed RCS reducer with a total dimension of 180 × 180 mm2 is fabricated and measured, the 10 dB RCS reduction bandwidth of theoretical simulation and experimental measurement are basically consistent, and the performance improvement of 8 dB RCS reduction in the experimental results can be attributed to the dispersion effects of the dielectric substrate. With a better figure of merit, our efforts may serve as a useful exemplar for the economical CMS architecture in radar evasive applications. [ABSTRACT FROM AUTHOR]

Selective infrared radiation is crucial for achieving infrared stealth and heat dissipation. Artificially designed superstructure film (SF) provides several advantages for controlling and modulating infrared radiation, making them a promising solution for these applications. The research described in this work has successfully produced broadband selective infrared radiation by using a surface made up of circular patches that are combined. Numerical simulations show that this SF can achieve broadband selective radiation with 3–5 μm mid-wave infrared (MWIR) suppression and 8–14 μm long-wave infrared (LWIR) emission. The spectral selectivity can be easily switched to high emissivity in MWIR and low emissivity in LWIR by simply changing the basal layer. The resonance mechanism for achieving broadband spectral selectivity in the SF may be due to a combination of multimode plasmon resonances that are induced by the structural nonrotational symmetry of the circular patches. By applying the selective radiation SF on the tail nozzle or the vehicle, the effect of thermal management is very significant. Selective radiation SF can reduce radiant energy in the 3−5 μm band by a significant amount at 500 °C, resulting in a 46 °C cooler temperature than that at the body without the SF. At 80 °C, radiated energy in the 8–14 μm band is also considerably reduced and the temperature is 10 °C lower than that of the body without the SF. There will be obvious advantages in potential applications for infrared stealth and heat dissipation by the designed SF, a simple and convenient manufacturing process. [ABSTRACT FROM AUTHOR]

Seven grain quality traits were tested in the panel of 188 winter wheat accessions from Xinjiang. Twelve co-associated genetic loci were detected in four different environments via GWAS, explaining 6.021%-31.467% phenotypic variation. Two pleiotropism loci, located on chromosomes 6A and 2B, associated with protein content and settlement value, protein content and bulk density of wheat. Five pleiotropism loci, located on 3A, 1B, 6B, 7B, and 7D, shared by protein content and wet gluten content. One pleiotropism locus, located on 5B chromosome, associated with settlement value, bulk density of wheat and grain hardness. Three pleiotropism loci located on 7A, 3B, and 2D, respectively, which shared by protein content, settlement value, and wet gluten content, while one pleiotropism locus with unknown site was also associated with protein content, settlement value, and wet gluten content. These associated loci or genes might be employed to select favorite wheat genotypes, and cultivate elite wheat genotypes via marker-assisted selection in wheat quality breeding. Candidate genes at stable loci associated with multiple traits were searched, and 11 candidate genes that might be related to wheat grain quality with multiple traits and environments were screened. Among them, TraesCS6B01G347500 encoded a storage and transportation protein, TraesCS1B01G395400 encoded a carbohydrate transport protein/sugar transport protein, and TraesCS2D01G246500 gene encoded a protein ESKIMO1 related to cold tolerance, salt tolerance, and water conservation. These genes can be used as candidate genes for allelic variation analysis and marker development, provide molecular tools for wheat marker assisted selection breeding. [ABSTRACT FROM AUTHOR]

The popularity of metasurfaces (MSs) has been continuously grown due to their powerful ability to manipulate electromagnetic waves. One of their important application areas is radar stealth technology, in particular, the realization of radar cross section (RCS) reduction. However, the high costs of substrate material limit its large-scale applications. In this paper, a binary digital coding metasurface (DCM) with novel modified ‘crusades-like’ cell topologies is proposed and implemented using a low-cost FR4 substrate to achieve broadband RCS reduction (RCSR). To realize the 1-bit DCM, initially, two elements with rotational symmetry are chosen for polarization insensitive properties while considering an unconventional phase deviation criteria. Next, the optimal hybrid coding layout is given out by using a genetic algorithm and antenna array theory. Last, the proposed novel MS prototype composed of 40 × 40 unit cells is fabricated and measured to validate the RCSR behaviour predicted by full-wave simulation. The results show a good consistency between the theoretical simulation and experimental measurement from 7.9 to 15.8 GHz. In addition, the simulation results indicate that the designed MS features high angular stability. Our work may provide a promising approach and good reference for the low-cost MS design in radar stealth applications. [ABSTRACT FROM AUTHOR]

Objectives:Using microarray analysis, we previously showed that many lncRNAs are differentially expressed in colorectal cancer (CRC) tissues compared with normal tissues, suggesting that lncRNAs may be involved the initiation and progression of CRC. In this study, we investigated the expression and function of lncRNA-RP11-317J10.2 in human CRC tissues and cell lines. Methods:LncRNA-RP11-317J10.2 expression level was analyzed in 52 colon cancer and cell lines. We used shRNA to knock-down the expression of RP11-317J10.2, and then proliferation assay, colony formation assay, Boyden chamber assay, FACS and Kaplan–Meier survival analysis were performed to explore the biological effect of RP11-317J10.2. Cyclin D1 protein level was detected by Western blot. Results:LncRNA-RP11-317J10.2 is downregulated in CRC and decreased expression is significantly associated with advanced tumor stage, larger tumor size and poor prognosis. RNA interference-mediated knockdown of lncRNA-RP11-317J10.2 in CRC cells promotes G1-to-S cell cycle transition, enhances invasiveness and facilitates cell growthin vitroand in mouse tumor xenograft models. Cyclin D1 was upregulated by lncRNA-RP11-317J10.2 knockdown, and co-expression of cyclin D1-targeting siRNA abrogates the pro-tumorigenic effects of lncRNA-RP11-317J10.2 knockdown. Conclusions:This study reveals a crucial role for lncRNA-RP11-317J10.2 in CRC growth and invasion via upregulation of cyclin D1 expression and suggests that expression of this lncRNA may be a potential prognostic biomarker for CRC. [ABSTRACT FROM PUBLISHER]

Forecasting the rapid intensification of tropical cyclones over offshore areas remains difficult. In this article, the Weather Research and Forecast (WRF) model was used to study the rapid intensification of Typhoon Haikui (1211) off the shore of China. After successful simulation of the intensity change and track of the typhoon, the model output was further analyzed to determine the mechanism of the rapid change in intensity. The results indicated that a remarkable increase in low-level moisture transportation toward the inner core, favorable large-scale background field with low-level convergence, and high-level divergence played key roles in the rapid intensification of Typhoon Haikui in which high-level divergence could be used as an indicator for the rapid intensity change of Typhoon Haikui approximately 6 h in advance. An analysis of the typhoon structure revealed that Typhoon Haikui was structurally symmetric during the rapid intensification and the range of the eyewall was small in the low level but extended outward in the high level. In addition, the vertically ascending motion, the radial and tangential along wind speeds increased with increasing typhoon intensity, especially during the process of rapid intensification. Furthermore, the intensity of the warm core of the typhoon increased during the intensification process with the warm core extending outward and toward the lower layer. All of the above structural changes contributed to the maintenance and development of typhoon intensity. [ABSTRACT FROM AUTHOR]

Using the National Center for Environmental Prediction reanalysis data on 1.0° × 1.0° grids and data from the Tropical Cyclone yearbook (2000), a diagnostic analysis and numerical simulation were performed to investigate the characteristics and mechanism underlying the rapid weakening of typhoon Xangsane. The results show that a sharp decline in the intensity of typhoon Xangsane resulted from its movement into the cool sea surface temperature area in the East China Sea, the intrusion of cold air from the mainland into the typhoon, and a rapid increase of the vertical wind shear in the surrounding environment. An important factor that led to the demise of the typhoon was a significant decrease in the moisture transport into the typhoon. Furthermore, the results of the numerical simulation and sensitivity experiments indicate that sea surface temperature largely modulated the rapid weakening of typhoon Xangsane. [ABSTRACT FROM AUTHOR]