Two-step Structural Design of Mesh Antennas for High Beam Pointing Accuracy

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.

The expression and function of long noncoding RNAs in hepatocellular carcinoma

With the deepening of the genome project study,attention on noncoding RNAs is increasing.Long noncoding RNAs(lncRNAs)have become a new research hotspot.A growing number of studies have revealed that lncRNAs are involved in tumorigenesis and tumor suppressor pathways.Aberrant expressions of lncRNAs have been found in a variety of human tumors including hepatocellular carcinoma(HCC).In this review,we provide a brief introduction to lncRNA and highlight recent research on the functions and clinical significance of lncRNAs in HCC.

Clinical and pathological features of miR-10b and RHOC gene expression in hepatocellular carcinoma

Aberrant expression of microRNAs(miRNAs)was reported frequently in different human cancers.The major role of miRNA is targeting 30-UTR of coding gene and causing translational repression or mRNA degradation.miR-10b overexpression was reported to promote breast cancer metastasis by up-regulating RHOC expression.But its expression in hepatocellular carcinoma(HCC)remains unclear.Our study indicated that the expression of miR-10b was different in HCC and adjacent tissue samples,and reduced expression of miR-10b in HCC was related tovein invasion.High-level expression of RHOC was also related to vein invasion in HCC.But no correlation was found between miR-10b and RHOC expression.These results suggest that miR-10b and RHOC are independent predictors of HCC invasion and metastasis.

Application of artificial intelligence in diagnosis of pulmonary tuberculosis

Tuberculosis(TB)is an infectious disease caused by Mycobacterium tuberculosis.Although the diagnostic technology of pulmonary tuberculosis(PTB)has advanced,accurate and differential diagnoses of PTB are still challenging.In recent years,the rapid development of artificial intelligence(AI)and its wide application in the medical field have provided new opportunities for diagnosing and treating TB and PTB.The machine learning model of AI has not only helped physicians improve diagnostic accuracy,but also enabled them to make early preventive diagnoses for individuals at increased risk of infection.Furthermore,AI can guide physicians to formulate targeted treatment strategies for PTB patients with different conditions.