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Active phased array antenna (APAA) is a representative of complex electronic equipment, and it plays significant roles in scenarios such as battlefield situation perception, aviation guidance, and communication. It has become the core equipment in land, navigation, and aeronautical applications. With the continuous improvement of technical changes and military requirements, the working frequency band, pointing accuracy, gain, and low sidelobe level of APAA increase, and the multi-disciplinary design contradiction between antenna electrical performance and structure and temperature becomes increasingly prominent. As a result, the electrical performance of APAA in service is prone to be affected by the external complex environments. The structural-electromagnetic-thermal (SET) coupling problem has become a key problem restricting the development of APAA. This paper has summarized the structural features and environmental loads of advanced APAA on different platforms and provided design basis and principle for antenna designer. And then the SET coupling theory of APAA has been introduced, which can be applied in both the design and manufacturing stage, as well as the performance control technology in service environment of APAA. This theory helps to analyze the impact of environmental factors, such as antenna structure deformation, radome high-temperature ablation, and feed errors, on the antenna's performance. For 128 × 768 spaceborne array antenna, in the range of 25∼85°C, the gain of antenna decreases with the increase of operating temperature and decreases by 0.015 dB with each increase of 1°C. The key design parameters in the fields of antenna manufacturing accuracy, efficient heat dissipation, and lightweight design are also analysed; for 32 × 32 rectangular planar phased array antenna, the gain of antenna decreases by 2.715 dB when the random error of installation position in x, y, and z direction reaches 1/10 of the wavelength. In addition, condition monitoring, displacement field reconstruction, and electrical performance compensation of APAA have also been touched to help engineers maintain and guarantee the antenna performance throughout its life cycle. Finally, the future research direction of SET technology of APAA has been discussed, and SET technology is extended to more fields such as antenna parameter uncertainty, high-frequency circuit electronics manufacturing, and electronic equipment performance guarantee. [ABSTRACT FROM AUTHOR]

Vaginal microbiota is closely associated with women's health, however, the correlation between HPV‐related cervical disease (HRCD) and vaginal microbiota is still obscure. In this study, patients with HRCD (n = 98) and healthy controls (n = 58) in Hangzhou were recruited, and their vaginal microbiota were collected and analyzed. The composition of the vaginal microbial community was explored, and a disease classification model was developed by random forest algorithm. The results suggested that the diversity of vaginal microbiota was significantly higher in HRCDs than that in healthy controls (p < 0.05). Firmicutes is the dominant phylum in vaginal microbiota, and Lactobacillus was identified as the most altered genus between two groups (p < 0.01). Kyoto Encyclopedia of Genes and Genomes analysis suggested the difference in vaginal microbial community functions between two groups. Furthermore, we identified 10 biomarkers as the optimal marker sets for the random forest model and found a higher probability of disease values in HRCD group in discovery cohort (p < 0.0001), with an area under the receiver operating characteristic curve reaching 89.7% (95% confidence interval: 78.3%–100%). We further validated the model in both validation and independent diagnosis cohorts, confirming its accuracy in the prediction of HRCD. In conclusion, this study revealed the community composition of vaginal microbiota in HRCDs and successfully constructed a diagnostic model for HRCD. [ABSTRACT FROM AUTHOR]

Terrain adaptation and amphibious landing pose the greatest challenges for soft amphibious robots. Based on the principles of tortoises, this paper presents a fully 3D‐printed soft amphibious robot with four pneumatic bionic legs that are capable of bending in three dimensions. The gaits of the robot are described in six different ways and a dynamic model is developed for its control. In addition to linear motion (0.97 BL s−1) and turning (25.4° s−1) on rigid terrain, the robot can also maneuver on various surface conditions (such as hills, gaps, smooth slopes, gravel, sand, muddy terrain, and water), and even make an amphibious landing. These properties, together with the soft amphibious robot's continuous obstacle avoidance capabilities, high load‐carrying capacity (28 times its own weight), low cost, and high camouflage, allow for a wide variety of applications. [ABSTRACT FROM AUTHOR]

With the constant increase in communication requirements in modern society, the number and type of antennas on communication platforms have been increasing at an accelerating rate. This has led to a continuous increase in platform volume and weight, and the electromagnetic environment of antenna operating has increasingly worsened, seriously restricting the further development of communication systems. As a new communication system antenna type, a reconfigurable microstrip antenna can reconstruct operating frequencies, beam directions, etc., by changing the antenna structure to provide the good multifunction characteristics of a single antenna, avoiding the electromagnetic compatibility issues caused by numerous system antennas. At present, most of the research on reconfigurable antennas judges the influence of structural characteristics on electromagnetic characteristics by simulation, which has imposed restrictions on their development and application. Therefore, a reconfigurable antenna with a resonant frequency of 8.66 GHz and 15.26 GHz and a reconfigurable antenna with maximum radiation directions of 36.2° and −36.5° are designed in this paper, and the electromechanical coupling theory of the reconfigurable antennas is studied. The resonance frequency coupling model and the pattern function coupling model considering the structural deformation of a reconfigurable microstrip antenna are established. Within the applicable range of antenna structural parameters, the relative error between the resonance frequency coupling model and the pattern function coupling model is less than 5%, which meets practical engineering application requirements. Finally, the method is shown by experimentation to verify the accuracy and validity of the proposed electromechanical coupling model. [ABSTRACT FROM AUTHOR]

The top-down approach in designing and fabricating origami robots could achieve far more complicated functions with compliant and elegant designs than traditional robots. This study presents the design, fabrication, and testing of a reticular origami soft robotic gripper that could adapt to the shape of the grasping subject and grasp the subject within 80 ms from the trigger instance. A sensing mechanism consisting of the resistive pressure sensor array and flexible elongation sensor is designed to validate further the shape-adaptive grasping capability and model the rough shape and size of the subject. The grasping test on various objects with different shapes, surface textures, sizes, and living animals further validates the excellent grasping capabilities of the gripper. The gripper could be either actively triggered by actuation or passively triggered by a minimum of 0.0014 J disturbance energy. Such features make it particularly suitable for applications such as capturing underwater creatures and illegal drone control.

Objective: This study aimed to investigate the clinical and histological features affecting the survival of patients with early cervical squamous cell cancer treated with radical hysterectomy., Methods: We retrospectively analyzed clinical and histological data for patients with stage IB-IIA cervical cancer treated by radical hysterectomy at Zhejiang Cancer Hospital from August 2008 to January 2013., Results: A total of 1435 patients were included in the study. Cox regression analysis identified tumor size >4 cm, lymphovascular space involvement (LVSI), lymph node ratio (LNR), and squamous cell carcinoma antigen (SCC-Ag) >2.65 ng/mL as independent prognostic risk factors. Among 1096 patients without high pathological risk factors, the 5-year local recurrence rates for SCC-Ag ≤2.65 and >2.65 ng/mL were 6.6% and 25.7%, respectively. Among 332 patients with lymph node positivity, the overall survival rates for LNR ≤0.19 and >0.19 were 87.8% and 55.6%, respectively., Conclusions: LVSI, tumor size >4 cm, LNR >0.19, and SCC-Ag >2.65 ng/mL may predict a poor prognosis in patients with early cervical squamous cell cancer treated with radical hysterectomy. SCC-Ag >2.65 ng/mL may be a useful prognostic factor guiding the use of postoperative radiotherapy in patients without pathologic risk factors.

BACKGROUND This study aimed to analyze the changes in plasmacytoid dendritic cell (pDC) immunophenotypes when co-cultured with Caski cells and stimulated by human papillomavirus (HPV) E6 in vitro, and thus to discuss the immunoregulatory roles of pDCs in the tumorigenesis of cervical cancer. MATERIAL AND METHODS The immunophenotypic expression of pDCs was analyzed under stimulation of HPV E6 and co-culturing with Caski cells in vitro. RESULTS HPV E6 infection caused significantly increased expression of CD40 in HPV16 M and HPV16 H groups MyD88 in HPV16 M,HPV16 H, and HPV18L groups; and TRAF6 in HPV16 M, HPV16 H, and HPV18L groups. pDCs co-cultured with Caski cells showed significantly lower expression of MyD88 and TRAF6 compared with the control. CONCLUSIONS The expression of MyD88 and TRAF6 might vary in different stages of HPV infection. pDCs might regulate CD40 to participate in the tumorigenesis and progression of cervical cancer, but related mechanisms still need further investigation.

Background: KLF4 is a zin-finger transcription factor that plays roles in differentiation, development, and proliferation. Recent studies show that KLF4 is involved in tumorigenesis and somatic cells reprogramming. Metastasis is the primary cause of death in patients with lung cancer, and its biological mechanisms are poorly understood., Goals: In this study, we aim to explore the expression pattern and biological function of KLF4 in lung adenocarcinoma., Methods: We determined KLF4 in lung adenocarcinoma tissue and cell lines, using immunohistochemistry and western blotting. And we further analyzed the correlation between KLF4 expression and clinicopathologic parameters. We restored KLF4 expression and studied its effect on lung adenocarcinoma cells in vivo and in vitro. Luciferase assay was used to study impact of KLF4 on activity of MMP2 promoter., Results: KLF4 is dramatically down-regulated in lung adenocarcinoma tissue and cell lines. Promoter methylation contributes to the down-regulation of KLF4. Down-regulation of KLF4 in lung adenocarcinoma tissue is significantly associated with reduced survival time. Restoration of KLF4 inhibits migration and invasion of lung adenocarcinoma cells in vitro. Metastases to lungs significantly decrease in mice intravenously injected with tumor cells overexpressing KLF4. KLF4 inhibits invasion and metastasis via suppressing MMP2 promoter activity., Conclusion: The ability of KLF4 to inhibit migration, invasion, and metastasis of lung tumor cells indicates a potential role of KLF4 as therapeutic target in lung adenocarcinoma. KLF4 might be utilized as a favorable biomarker for prognosis of lung adenocarcinoma patients., Competing Interests: Competing Interests: The authors have declared that no competing interest exists.