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This letter presents a design of four‐element wideband multiple‐input‐multiple‐output (MIMO) antenna with improved isolation that covering 1.9–5.2 GHz for 5G application. The basic structure of the proposed MIMO antenna is meandering monopole; a dual‐band is generated by involving meandering L‐shape strip and inverted‐F strip, then coupling with a parasitic strip to generate wideband. By etching two H‐shape slots and two split‐ring resonator slots at the ground can enhance the isolation between two adjacent input ports. Antenna elements are rotated symmetrically and vertically distributed around the dielectric plate, the overall dimension of the MIMO array is 54 mm × 120 mm × 13 mm. Reasonable layout can reduce the user's influence on the antenna performance, so that each antenna element can work normally. The prototype is simulated, fabricated and measured. A good impedance matching (return loss <− 10 dB), high isolation (<−16 dB), high total efficiency (>65%), and low envelope correlation coefficient (ECC < 0.05) were obtained across the operation bandwidth, the gain of the antenna is 6.1 dB at 3.6 GHz. Through measurement, it is found that the results are basically consistent with the simulation results, indicating that both wide bandwidth and high isolation are successfully achieved and can be well applied in 5G communication. [ABSTRACT FROM AUTHOR]

Objective. Nasopharyngeal carcinoma is particularly prevalent in Guangdong and Guangxi (southern China); the economic burden of nasopharyngeal cancer patients is heavy in China. This study is aimed at retrospectively analyzing the basic features and economic burden of newly diagnosed nasopharyngeal carcinoma patients admitted to the First Affiliated Hospital of Guangxi Medical University and at providing a scientific basis for nasopharyngeal carcinoma prevention and control strategies. Methods. The data of 3,727 nasopharyngeal carcinoma inpatients diagnosed from January 2012 to December 2020 were extracted from the Guangxi Nasopharyngeal Carcinoma Healthcare Big Data Management Information Platform. Basic demographic characteristics, duration of hospital stay, and hospitalization cost of nasopharyngeal carcinoma patients were collected and analyzed statistically. Results. The incidence period of nasopharyngeal carcinoma was primarily from 30 to 69 years of age, with the 40–49-year age group comprising the largest proportion of nasopharyngeal carcinoma patients, accounting for 34.18% of the patients with newly diagnosed nasopharyngeal carcinoma in the hospital. The male-to-female ratio was 2.87 : 1. There were 2,223 cases from rural areas, 2,153 from the Han ethnic group, and 1,460 from the Zhuang ethnic group, accounting for 59.65%, 55.77%, and 39.17% of the total number of cases, respectively. The average duration of hospitalization decreased whereas the average hospitalization cost increased annually. Multivariate analysis of hospitalization cost showed that the duration of hospital stay, rural/urban, and ethnicity was the main influencing factors: the longer the duration of hospital stay, the higher the hospitalization cost; patients from rural incurred lower costs than from urban; ethnic Zhuang patients incurred significantly lower costs than patients from other ethnicities. Conclusion. Early diagnosis and treatment should be actively carried out to reduce the incidence of nasopharyngeal carcinoma, especially for rural, ethnic Zhuang, and males in the 40–49-year age group patients. The future research on nasopharyngeal carcinoma will focus on exploring the pathogenesis of nasopharyngeal carcinoma, improving the screening system, and reducing the burden on patients, in order to further improve the survival rate and quality of life of patients with nasopharyngeal carcinoma. [ABSTRACT FROM AUTHOR]

Objective. To establish and validate a nomogram to predict the overall survival (OS) and cancer-specific survival (CSS) in patients with nasopharyngeal carcinoma (NPC) receiving radiotherapy by integrating multiple independent prognostic factors. Materials and Methods. Data from 5663 patients with NPC who received definite radiotherapy between 2004 and 2018 were included and divided into training and validation cohorts. Univariate and multivariate Cox regression analyses were performed to determine the independent prognostic factors of patients with NPC after radiotherapy. Thereafter, the predictive accuracy of the nomogram model was evaluated. Results. Age, race, marital status, pathological type, tumor size, T stage, N stage, M stage, American Joint Committee on Cancer stage, and chemotherapy were independent factors affecting the prognosis of patients with NPC receiving radiotherapy. Nomograms with a concordance index of 0.726 (95% confidence interval (CI): 0.675–0.777) and 0.732 (95% CI: 0.680–0.785) were able to predict OS and CSS, respectively. The area under the curve showed excellent predictive performance. Additionally, the calibration curve indicated that the predicted survival rate was consistent with the actual survival rate, and the decision curve indicated its clinical value. The established risk stratification system was able to accurately stratify patients receiving radiotherapy for NPC into three risk subgroups with significant differences in prognosis (P < 0.05). Conclusions. The constructed nomogram had good prognostic performance and could be used as an effective tool to evaluate the prognosis of patients with NPC after radiotherapy. This nomogram could be further used to guide clinical decisions and personalized treatment plans. [ABSTRACT FROM AUTHOR]