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Background and aimsAn increasing number of studies have confirmed that non-textbook outcomes (non-TO) are a risk factor for the long-term outcome of malignant tumors. It is particularly important to identify the predictive factors of non-TO to improve the quality of surgical treatment. We attempted to construct two nomograms for preoperative and postoperative prediction of non-TO after laparoscopic hepatectomy for hepatocellular carcinoma (HCC).MethodsPatients who underwent curative-intent hepatectomy for HCC between 2014 and 2021 at two Chinese hospitals were analyzed. Using univariate and multivariate analyses, the independent predictors of non-TO were identified. The prediction accuracy is accurately measured by the receiver operating characteristic (ROC) curve and calibration curve. ROC curves for the preoperative and postoperative models, Child–Pugh grade, BCLC staging, and 8th TNM staging were compared relative to predictive accuracy for non-TO.ResultsAmong 515 patients, 286 patients (55.5%) did not achieve TO in the entire cohort. Seven and eight independent risk factors were included in the preoperative and postoperative predictive models by multivariate logistic regression analysis, respectively. The areas under the ROC curves for the postoperative and preoperative models, Child–Pugh grade, BCLC staging, and 8th TNM staging in predicting non-TO were 0.762, 0.698, 0.579, 0.569, and 0.567, respectively.ConclusionOur proposed preoperative and postoperative nomogram models were able to identify patients at high risk of non-TO following laparoscopic resection of HCC, which may guide clinicians to make individualized surgical decisions, improve postoperative survival, and plan adjuvant therapy against recurrence.

Background & aimsThe long-term prognosis of patients with metabolic syndrome (MS) and hepatitis B virus-related hepatocellular carcinoma (HBV-HCC) after radical hepatectomy remains unclear. The purpose of this study was to elucidate the effect of MS on long-term survival for patients with HBV-related HCC after hepatectomy.MethodsPatients with HBV-HCC after hepatectomy were included. Patients were stratified into MS-HBV-HCC and HBV-HCC groups. Clinical features and surgical outcomes were compared between the two groups, and COX regression analysis was used to determine independent risk factors associated with overall survival (OS) and recurrence-free survival (RFS).Result389 patients (MS-HBV-HCC group: n=50, HBV-HCC group: n=339) were enrolled for further analysis. Baseline characteristics showed that patients with MS-HBV-HCC were associated with a high rate of elderly patients, ASA score, and co-morbid illness, but a lower rate of anatomy hepatectomy. There were no significant differences in perioperative complications. After excluding patients who relapsed or died within 90 days after surgery, multivariate Cox regression analysis showed MS was an independent risk factor of OS (HR 1.68, 95% CI 1.05-2.70, P = 0.032) and RFS (HR 1.78, 95% CI 1.24-2.57, P = 0.002).ConclusionMS is an independent risk factor for poor OS and RFS in HBV-infected HCC patients after radical hepatectomy. This suggests that we need to strengthen postoperative follow-up of the relevant population and encourage patients to develop a healthy lifestyle.

In the face of the shortage of radio spectrum resources, the contradiction between supply and demand and other issues, data compression technology can ensure data integrity while saving storage space, effectively improving the utilization of spectrum resources. This article first makes lossless Huffman coding, LZ77, LZ78, and LZW algorithms. The compression technology is briefly introduced, and the application of various algorithms and the corresponding advantages and disadvantages are analyzed with examples. Secondly, for the radio signal data of the radio monitoring station in Gansu Province, the performance of these commonly used lossless compression algorithms is compared. Finally, the experimental test result data proves that when the compressed file is large, the LZ series algorithm has a better compression effect than the Huffman algorithm. In LZ series, LZW algorithm has the best compression effect, LZ77 algorithm has the worst compression effect, and the compression effect of LZ78 is between them. When the compressed file is small, because the data in the compressed file is less, the compression effect of several algorithms is not obvious.

Estimating the value of water resources not only forms the basis of water rights transactions between upstream and downstream and eco-compensation standards, but also provides scientific data for the reasonable establishment of local water prices and promotes sustainable use and efficient management. Here, we estimate the economic value of the water resources of the upper reaches of the Xin'an River basin. Our purpose is to establish theoretical support for eco—compensation standardization and provide data for the protection of water resources and water price reform.

With the rapid development of wind power in China, the impact of large-scale wind farms on the power grid becomes increasingly serious. Among which, the voltage fluctuation at the PCC (point of common coupling), has attracted a lot of attention. In this paper, the effects of voltage and reactive power control on wind farms are analysed based on the nine zone diagram method. Firstly, the modified nine zone diagram for the wind farm substation is presented. And then, the characteristics of voltage and reactive power control are discussed from the viewpoint of modified nine zone diagram. Furthermore, the control strategy of voltage and reactive power is designed based on the modified nine zone diagram. Finally, simulations of an actual wind farm are done on to verify the feasibility and effectiveness of the proposed control strategy.

Nine zone diagram is commonly used to keep voltage stability and reactive voltage balance by changing reactive power compensation equipment or the transformer tap in the substation. In this paper, the principles of voltage and reactive power control based on nine zone diagram are reviewed, and then the control effect of reactive power compensation and transformer tap with different types of load model is analyzed. In the end, the effect of six different types of load on voltage control is simulated, and the results show that: the change trend of voltage or reactive power is roughly the same when changing reactive power compensation; the change trend of the voltage is roughly the same, but the change trend of reactive power has great difference when changing transformer tap.

High speed electrooptic phase modulators play very important roles in the high-speed optical fiber communication system, microwave photonic system, and coherent optical communication system, due to their advantages of bias voltage free and linear modulation. As an intrinsic parameter, the half-wave voltage of an electrooptic phase modulator has been characterized by using an electrical spectrum method and an optical spectrum method in the last two decades. The optical spectrum method is generally limited by the line-width of the laser source and the resolution of the available optical spectrum analyzer, while the electrical spectrum method requires the conversion from phase modulation to intensity modulation before photodetection, since a phase modulator generates a phase modulated optical signal with constant envelope. The major difficulty in the electrical spectrum method lies in the extra calibration for the responsivity fluctuation in the photodetection. In this paper, a novel self-calibrated measurement of half-wave voltage of electrooptic phase modulators is carried out based on the optical heterodyning between the two-tone phase modulated sidebands and the frequency-shifted carrier. The method achieves a self-calibration measurement, and avoids the effect of the responsivity fluctuation in the photodetection by setting a specific frequency relationship between the two-tone microwave signals. Moreover, it extends the measuring frequency range to the double bandwidth of photodetection and spectrum analysis. Compared with the optical spectrum method, the proposed method achieves very high frequency resolution measurement, and simultaneously avoids the line-width influence of laser source by use of two-tone heterodyning. Compared with the traditional electrical spectrum method, our method works under no small-signal assumption nor photodetection calibration, and eliminates the limits of electrical driving amplitude and operating wavelength. Moreover, it decreases by at least half bandwidth requirement for the photodetector and spectrum analyzer. Our experimental demonstration shows that the measured half-wave voltages of the electrooptic phase modulator obtained by our method agree well with the data measured by the optical spectrum method, and the two-tone heterodyning method greatly improves the measurement range and frequency resolution. The proposed measurement method provides a very simple analysis method for the microwave characterization of high-speed electrooptic phase modulators, which is also a reference for other optoelectronic devices.

Diamond films are deposited on Mo substrates by dc hot-cathode plasma chemical vapor deposition method using a CH4-H2-CO2 gas mixture. Adjusting the flow of CO2, we study the relevant influence on surface morphology, grain orientation and crystalline quality of films with scanning electron microscopy, x-ray diffraction, Raman spectroscopy, respectively. The results show that grain orientation of the films has a transition with the increasing CO2 addition, from (100) orientation to (110) orientation and then (111) orientation. The crystalline quality is improved but the growth rate is decreased by raising the flow of CO2. The experimental results are also discussed briefly.