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A thin laminated composite is proposed in this article for highly efficient microwave absorption at both high frequency and low frequency. It is composed of two layers of carbon-fiber-reinforced planar structure. In each layer, periodically arranged fiber array with the axes of the fibers parallel to each other is embedded into a ceramic matrix which is used to bind the fibers together and to provide necessary mechanical or chemical properties. Stacking up two layers of the planar structure with the fibers in different layers orientated into different directions produces a lamina which can be further parallely stacked up to provide the whole laminated material. The influence of the structural and electromagnetic parameters on the microwave absorption efficiency is first studied in detail with scattering matrix and boundary-mode matching method. Then the genetic algorithm and the sequential quadratic programming methods are used to form a two-step strategy based on the mode-matching method to optimize the structural and electromagnetic parameters for a highly efficient microwave absorption in both high-frequency and low-frequency bands. Numerical examples are also given to demonstrate the high absorption efficiency of the designed laminated material.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been rampantly threatening much more people life, thus timely and precise countermeasures against SARS-COV-2 were a matter of urgency. Here, integrated bio-information analyse were used for deeply understanding the process of SARS-COV-2 infection. And it was demonstrated that pathways related to antivirus response, innate immune response, and type 1 interferon pathways were dominantly enriched in Covid-19, while neutrophil degranulation, inflammatory reaction and Covid-19 adverse outcome were also assigned significance. PPI network revealed that type 1 interferon pathways related genes ranked as the hub genes in Covid-19, and among these genes OASL, IFIT1,IFIT2,IFIT3 might be typically drug targeted, which was demonstrated by the cerna network and drug interaction network. Our research in the end meant to fundamentally achieve recommended strategies to benefit people suffering from SARS-COV-2 infection.

Clinical-practice observations have revealed that novel coronavirus pneumonia is related to the dampness pathogen; most patients show a systemic inflammatory response syndrome (SIRS), and patients with a severe form of the disease have sepsis.The current study aimed to explore the role of Traditional Chinese medicine (TCM) and western medicine in the treatment of COVID-19.The research team developed a case study.The study took place at the Nanchang Ninth Hospital in Nanchang, China.The participant was a 44-year-old female patient with diabetes who was a hepatitis B carrier. She was admitted to the hospital and diagnosed with novel coronavirus pneumonia at admission.She was treated for seven days with Western medicine, at which time the nucleic acid test for the virus was negative; however, she still had flaky glass shadows in the lungs. She was then treated with TCM.The patient reached the discharge standard on February 29. A recheck was performed on March 6, six days after discharge. Her chest CT showed that the two lung lesions continued to be absorbed, and the viral nucleic acid test was negative.For diagnosis and treatment of novel coronavirus pneumonia, the determination of the use of six channels or Wei-qi-Ying-blood differentiation needs to be combined with syndrome differentiation and to comply with the body's process of eliminating pathogens. The recovery of qi, blood and body fluid, and SIRS should be taken into account.

Gallbladder carcinoma (GBC) is the most common biliary tract malignancy with the lowest survival rate, primarily arising from chronic inflammation. To better characterize the progression from inflammation to cancer to metastasis, we performed single-cell RNA sequencing across samples of 6 chronic cholecystitis, 12 treatment-naive GBCs, and 6 matched metastases. Benign epithelial cells from inflamed gallbladders displayed resting, immune-regulating, and gastrointestinal metaplastic phenotypes. A small amount of PLA2G2A+ epithelial cells with copy number variation were identified from a histologically benign sample. We validated significant overexpression of PLA2G2A across in situ GBCs, together with increased proliferation and cancer stemness in PLA2G2A-overexpressing GBC cells, indicating an important role for PLA2G2A during early carcinogenesis. Malignant epithelial cells displayed pervasive cancer hallmarks and cellular plasticity, differentiating into metaplastic, inflammatory, and mesenchymal subtypes with distinct transcriptomic, genomic, and prognostic patterns. Chronic cholecystitis led to an adapted microenvironment characterized by MDSC-like macrophages, CD8+ TRM cells, and CCL2+ immunity-regulating fibroblasts. By contrast, GBC instigated an aggressive and immunosuppressive microenvironment, featured by tumor-associated macrophages, Treg cells, CD8+ TEX cells, and STMN1+ tumor-promoting fibroblasts. Single-cell and bulk RNA-seq profiles consistently showed a more suppressive immune milieu for GBCs with inflammatory epithelial signatures, coupled with strengthened epithelial-immune crosstalk. We further pinpointed a subset of senescence-like fibroblasts (FN1+TGM2+) preferentially enriched in metastatic lesions, which promoted GBC migration and invasion via their secretory phenotype. Collectively, this study provides comprehensive insights into epithelial and microenvironmental reprogramming throughout cholecystitis-propelled carcinogenesis and metastasis, laying a new foundation for the precision therapy of GBC.

Neoantigen-directed therapy lacks preclinical models recapitulating neoantigen characteristics of original tumors. It is urgent to develop a platform to assess T cell response for neoantigen screening. Here, immunogenic potential of neoantigen-peptides of tumor tissues and matched organoids (n = 27 pairs) are analyzed by Score tools with whole genome sequencing (WGS)-based human leukocyte antigen (HLA)-class-I algorithms. The comparisons between 9203 predicted neoantigen-peptides from 2449 mutations of tumor tissues and 9991 ones from 2637 mutations of matched organoids demonstrate that organoids preserved majority of genetic features, HLA alleles, and similar neoantigen landscape of original tumors. Higher neoantigen load is observed in tumors with early stage. Multiomics analysis combining WGS, RNA-seq, single-cell RNA-seq, mass spectrometry filters out 93 candidate neoantigen-peptides with strong immunogenic potential for functional validation in five organoids. Immunogenic peptides are defined by inducing increased CD107aCD137IFN-γ expressions and IFN-γ secretion of CD8 cells in flow cytometry and enzyme-linked immunosorbent assay assays. Nine immunogenic peptides shared by at least two individuals are validated, including peptide from TP53

A well-designed reflector surface with high beam pointing accuracy in electromagnetic performance is of practical significance to the space application of cable mesh reflector antennas. As for space requirements, circular polarizations are widely used in spaceborne antennas, which usually lead to a beam shift for offset reflectors and influence the beam pointing accuracy. A two-step structural design procedure is proposed to overcome the beam squint phenomenon for high beam pointing accuracy design of circularly polarized offset cable mesh reflectors. A simple structural optimal design and an integrated structural electromagnetic optimization are combined to alleviate the beam squint effect of circular polarizations. It is implemented by cable pretension design and adjustment to shape the offset cable mesh surface. Besides, in order to increase the efficiency of integrated optimization, an update Broyden-Fletcher-Goldfarb-Shanno (BFGS) Hessian matrix is employed in the optimization iteration with sequential quadratic programming. A circularly polarized offset cable mesh reflector is utilized to show the feasibility and effectiveness of the proposed procedure. A high beam pointing accuracy in order of 0.0001o of electromagnetic performance is achieved.

In robust optimization, double-looped structures are often adopted where the outer loop is used to seek for the optimal design and the optimization performed in the inner loop is for the robustness assessment of the candidate solutions. However, the double-looped techniques usually will lead to a significant increase in computational efforts. Therefore, in this paper, a new robustness index is developed to handle bounded constraints on performance variation where no optimization run is required for the robustness evaluation work in the inner loop. The computation of this new index is based on the sensitivity Jacobian matrix of the system performances with respect to the uncertainties and it can quantitatively measure the maximal allowable magnitude of system variations. By introducing this index, the robust design problem can be reformulated as a deterministic optimization with robustness indices requirements. Two numerical examples are tested to show the effectiveness and efficiency of the proposed approach, whose solutions and computational efforts are compared to those from a double-looped approach proposed in previous literature.

In the area of structural design of reflector antennas, the existing researches mainly focus on size/shape optimization or just optimizing for structural performances (e.g., the reflector surface accuracy). Reflector antennas are one kind of equipment which is finally judged by its electromagnetic performances, and topology optimization has been proven a powerful method for structural design. In this paper, an integrated thermal-structural-electromagnetic (TSE) analysis procedure based on topology variables for reflector antennas is established for the first time. Then, topology optimization of the backup structure (BUS) of reflector antennas is developed and solved by genetic algorithms (GA) with bit-matrix representation of chromosome. The proposed optimization design method takes both the electromagnetic performance (antenna gain) and structure performance (total weight) into consideration. Numerical examples of BUS topology optimization of maximum gain with weight constraint are carried out. For comparison, a traditional minimum compliance design is also performed. The results illustrate the validity and effectiveness of the proposed method in the topology optimization of reflector antennas.

Manufacturing errors can result in variation of the cable tensions and degradation of the RF performance of cable-network antennas. To compensate the effects of the manufacturing errors, a novel shape control procedure, which takes the RF performance into consideration, is presented. Both the boundary cables and the tension ties are selected as adjustable cables. Sensitivity analysis is adopted to evaluate the influence of the unstrained cable lengths on the RF performance and cable tensions. The antenna performance is finally expressed as the incremental form of the adjustable cable lengths on the basis of the sensitivity analysis. A mathematical model of the shape control procedure is established and solved using optimization strategy. The proposed shape control method is applied to a 10-m diameter cable-network antenna. Numerical results show that the directivity of the antenna is more sensitive to the boundary cable lengths, while the tension in a cable is much more sensitive to the length changes of itself, the cables connected to it, and the boundary cables. Comparisons of the directivities and tensions before and after shape control demonstrate the feasibility of the proposed shape control method and recommend the antenna RF performance as the shape control objective.

Inevitable manufacturing errors and inconsistency between assumed and actual boundary conditions can affect the shape precision and cable tensions of a cable-network antenna, and even result in failure of the structure in service. In this paper, an analytical sensitivity analysis method of the shape precision and cable tensions with respect to the parameters carrying uncertainty was studied. Based on the sensitivity analysis, an optimal design procedure was proposed to alleviate the effects of the parameters that carry uncertainty. The validity of the calculated sensitivities is examined by those computed by a finite difference method. Comparison with a traditional design method shows that the presented design procedure can remarkably reduce the influence of the uncertainties on the antenna performance. Moreover, the results suggest that especially slender front net cables, thick tension ties, relatively slender boundary cables and high tension level can improve the ability of cable-network antenna structures to resist the effects of the uncertainties on the antenna performance.

From the viewpoint of geometrical optics, dielectric radome degrades the electromagnetic performance of the enclosed antenna by distorting the amplitude distribution and phase distribution of aperture field, of which the latter is mainly responsible for the distortion of far-field pattern. A novel method based on reflector shaping is proposed to compensate the phase distortion of aperture field caused by radome. The aperture field of the shaped reflector antenna possesses a phase distribution, which has an inverse trend when compared with the phase distortion caused by radome, thus making the aperture field become equiphase after transmitting through the radome. Two different antenna–radome systems are simulated and the results show that the proposed method is effective, particularly for compensating the distortion of far-field pattern such as the variation of sidelobe and null depth. Further analysis indicates that the shaping method is applicable to multifrequency-band antenna–radome systems.

A mechatronic method for the study of cable-net reflector antennas under mechanical random error is presented. In this method, the reflector mechanical random error and electrical radiation performance are taken as random variables, such that the electrical radiation performance based probability is analysed. A useful mathematical expression between the numerical characteristics of electrical radiation performance and mechanical parameters are developed. Applications on two cable-net reflector antennas are described and the simulation results demonstrate the effectiveness of the proposed method in the random error evaluation.

Since the curved surface of a cable-network reflector is generally approximated by regular flat facets, the electromagnetic performance of the cable-network reflector is determined by the size and shape of the facets. In many cases, the geometric approximation errors of the facets are periodically distributed on the surface, which can result in strong grating lobes. First, in this paper, the periodicity of the geometric approximation error and the effects of this periodicity on the EM performance are investigated. Second, the periodic geometric approximation errors of the regularly faceted configurations are disturbed by three proposed approaches, and three new types of surface configurations are thus formed. The first approach is to introduce radial direction disturbance parameters, the second one is to change the shape of the outlines and the last one is to use a Penrose-tiling-like configuration. The first two approaches are carried out in combination with the optimization strategies. Finally, the effects of the mentioned disturbance parameters on the EM performance are simulated, and some numerical examples are given to show that the surface configurations proposed in this paper can reduce the grating lobes level obviously, without either decreasing the gain or increasing the structural complexity of the cable-network reflectors.

The presence of radome inevitably degrades the electromagnetic (EM) performance of the enclosed antenna while the deformation of the radome may make the degradations even worse. This letter studies the effect of structural deformation of a metal space frame (MSF) radome on EM performance. Far field of the antenna-radome system is obtained by adding the far field transmitted through skin to the scattered field of elements, both fields varying when deformation occurs. A 20-m MSF radome is employed for simulation, whose structural deformation under wind and self-weight is analyzed using finite element method (FEM). Several significative characteristics about the effect of deformation on EM performance are pointed out.

Modern radomes are commonly made of composites, whose material properties inevitably have errors due to the complicated manufacturing process, thus degrading the electromagnetic (EM) performance of radomes. In this letter, both systematic and random material properties errors are introduced in the EM analysis of radomes. A statistical method is proposed, which relates the random material properties errors to the EM performance of radomes. The tolerance of material properties, including relative permittivity and loss tangent, are determined from experiment. Several significative characteristics about the effect of material properties errors on EM performance are provided. Then, the compensation method through modifying the geometrical thickness is applied to improve the EM performance of radomes with material properties errors, which is proved to be effective.

Cable mesh structure is an important way to construct large space deployable antennas. Due to inevitable manufacturing and assembly errors and external environment disturbance, the reflector surface of cable mesh antennas has to be carefully adjusted to achieve required accuracy. This is achieved by altering the length of some cables capable of adjustment. In this paper a shape adjustment procedure based on optimization is presented. A rigorous cable element is first derived, which can treat the cable length variation and the geometric nonlinearity of cable mesh structures. Then the incremental expressions of the reflector surface displacement and the tension exerted on the rim truss are developed, and the surface error is explicitly related to the cable length variation. Finally the shape adjustment procedure is converted into a sequential quadratic programming problem which can effectively reduce the surface error and can be easily solved. A numerical example is presented to demonstrate the feasibility of the method.

Based on the concept of structural-electromagnetic field coupling, an approximation method is developed to analyze the radiation pattern for distorted reflectors. In this method, the integration point deformation is obtained by a local interpolation scheme which utilizes the same shape functions as that in the structural analysis for the radiation calculation. The phase error caused by the distortion is added to the far field integral which is computed on the structural element. Similar to the assembly of element stiffness matrices in Finite Element Method (FEM), the far field electrical vector is derived as a function of structural nodal displacements in a matrix form by collecting the integrals on structural elements. Simulation is performed with good results. The method can benefit the computation for a given reflector in the integrated structural-electromagnetic optimization design procedure.

Uncertainties can be introduced into the structural performance of cable-network antennas by inevitable manufacturing errors, which may result in failure in service. In this paper, robust optimization is first adopted to address the design of cable-network antenna structures with imperfect cable lengths. First, an analytical sensitivity analysis method is proposed to evaluate the effects of the uncertainties on the shape precision and cable tensions. Second, based on the sensitivities, the mathematical model of the robust design is established. At last, the proposed method is applied to a 3-m-diameter cable-network antenna structure. The analytical sensitivities are validated by comparing with the sensitivities computed by finite-difference method, and the feasibility of the presented robust design model is demonstrated by Monte Carlo simulations. The numerical experiments show that the robustness is greatly increased by the application of the robust design method. The results recommend that highe...

© 2019 European Association on Antennas and Propagation. A reconfigurable partially reflective surface (PRS) antenna with improved beam steering capability is proposed in this paper. Compared with our previous paper, the beam-steering angle can be enhanced from ±5° to ±17° with less active elements and a much smaller gain variation. It is realized by employing a compact reconfigurable metasurface as the PRS structure, which is located atop a probe-fed square patch antenna. A prototype antenna operating at 5.5 GHz is fabricated and measured. Good agreement between the simulated and measured results for the input reflection coefficients and radiation patterns is achieved, which validates the feasibility of the design principle.