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Tumor-size-stratified analysis on the prognosis of uterine sarcoma is insufficient. This study aimed to establish the tumor-size-stratified nomograms to predict the 3- and 5-year overall survival (OS) of patients with uterine sarcoma.The data analyzed in this study were obtained from the Surveillance, Epidemiology, and End Results (SEER) database. We collected data from patients with uterine sarcoma diagnosed between 2004 and 2015. According to the median tumor size of 7.8 cm, the enrolled patients were divided into two tumor size (TS) groups: TS7.8 cm and TS ≥7.8 cm. Patients in each group were randomly divided into the training and validation cohorts with a ratio of 7:3. Chi-square test was used to compare differences between categorical variables. Multivariate Cox regression models were used to identify significant predictors. We calculated the concordance index (C-index) and the area under the receiver operating characteristics curve (AUC) to validate the nomograms.Compared with TS7.8 cm group, TS ≥7.8 cm group had more patients of 45-64 years group, higher black race prevalence, higher proportion of myometrium tumor, higher stage, and higher grade; In the TS7.8 cm training cohort, six variables (age, race, marital status, tumor primary site, stage, and grade) were identified as significantly associated with OS in multivariate analysis. However in the TS ≥7.8 cm training cohort, only four variables (surgery on primary site, tumor size, stage, and grade) were significantly identified; The C-index of two nomograms were 0.80 and 0.73 in training cohorts, respectively, and the AUC values for 3- and 5-year OS predictions in training cohorts were all above 0.80. Similar results were observed in validation cohorts.This study found that the significant prognostic factors were different between two tumor size groups of uterine sarcoma patients. The tumor-size-stratified nomograms, which we constructed and validated, might be useful to predict the probability of survival for patients with uterine sarcoma.

text, 学術雑誌論文 / Journal Article, In order to improve the finishing efficiency of the Magnetic Abrasive Finishing process, we proposed a new MAF process with renewable abrasive particles using compound magnetic finishing fluid circulatory system in this paper. This new finishing process has a circulating system that uses a conveyor belt to renew the mixed abrasive particles. This not only maintains the stability of the finishing but also ensures that the processing does not need to be interrupted. In this study, we investigated the magnetic field distribution, finishing force, and finishing behavior of the processing area. Furthermore, we designed experimental device to finish the sus304 stainless steel plate, to verify the feasibility of this process and understand its characteristics through processing experiments. Moreover, the influence of important process parameters, including magnetic particles, abrasive particles, conveyor belt line speed and working gap, on the surface quality of the workpiece is studied through the experiment. The experimental results indicate that the present process can achieve stable processing of the material surface without interruption, and the surface roughness of the sus304 stainless steel plate has been improved from 273 nm to 23 nm through this process.

BACKGROUND The United Nations Sustainable Development Goals for 2030 include reducing premature mortality from noncommunicable diseases by one-third. Although previous modeling studies have predicted premature mortality from noncommunicable diseases, the predictions for cancer and its subcategories are less well understood in China. OBJECTIVE The aim of this study was to project premature cancer mortality of 10 leading cancers in Hunan Province, China, based on various scenarios of risk factor control so as to establish the priority for future interventions. METHODS We used data collected between 2009 and 2017 from the Hunan cancer registry annual report as empirical data for projections. The population-attributable fraction was used to disaggregate cancer deaths into parts attributable and unattributable to 10 risk factors: smoking, alcohol use, high BMI, diabetes, physical inactivity, low vegetable and fruit intake, high red meat intake, high salt intake, and high ambient fine particulate matter (PM2.5) levels. The unattributable deaths and the risk factors in the baseline scenario were projected using the proportional change model, assuming constant annual change rates through 2030. The comparative risk assessment theory was used in simulated scenarios to reflect how premature mortality would be affected if the targets for risk factor control were achieved by 2030. RESULTS The cancer burden in Hunan significantly increased during 2009-2017. If current trends for each risk factor continued to 2030, the total premature deaths from cancers in 2030 would increase to 97,787 in Hunan Province, and the premature mortality (9.74%) would be 44.47% higher than that in 2013 (6.74%). In the combined scenario where all risk factor control targets were achieved, 14.41% of premature cancer mortality among those aged 30-70 years would be avoided compared with the business-as-usual scenario in 2030. Reductions in the prevalence of diabetes, high BMI, ambient PM2.5 levels, and insufficient fruit intake played relatively important roles in decreasing cancer premature mortality. However, the one-third reduction goal would not be achieved for most cancers except gastric cancer. CONCLUSIONS Existing targets on cancer-related risk factors may have important roles in cancer prevention and control. However, they are not sufficient to achieve the one-third reduction goal in premature cancer mortality in Hunan Province. More aggressive risk control targets should be adopted based on local conditions.

With the development of semiconductors, optics, aerospace, and other fields, the requirements for surface finish are constantly increasing. This requires not only better surface quality but also higher finishing efficiency. In order to improve the surface quality, the magnetic abrasive finishing process using an alternating magnetic field was proposed in the previous research. In this process, the magnetic clusters constantly fluctuate due to the periodic change of the current, thereby realizing the circulation of the abrasive particles in contact with the workpiece. It has been proved through previous studies that a better surface quality can be obtained in an alternating magnetic field. However, there are still some unclear mechanisms. For example, the fluctuation of magnetic cluster mainly depends on the change of current, but it is not clear which current change mode is more suitable for improving finishing efficiency and surface quality. Therefore, in this study, the influence of the current change mode on the magnetic field, finishing force, and finishing characteristics are discussed. Furthermore, SUS304 stainless steel plate was used as the object to conduct a series of experiments. According to the experimental results, when the abrasive particles are WA#8000, the average diameter of the magnetic particles is 75 μm, and the frequency is 1 Hz; in the case of pulse current with a duty cycle of 80%, a higher material removal rate can be achieved. The material removal rate is 1.7 times that of the static magnetic field and 1.45 times that of the sinusoidal alternating magnetic field.

Magnetic abrasive finishing (MAF) is an effective surface finishing method. At present, most of the research on plane MAF focuses on finishing characteristics. However, due to the “edge effect” of the magnetic field and the rotational movement of the magnetic brush, the uniformity and flatness of the finished surface are poor. In order to further improve the accuracy of the finished surface, the surface uniformity and flatness are improved by changing the shape of the magnetic pole and the trajectory of the magnetic brush. At the same time, the surface flatness is evaluated not only by the maximum height difference of the cross section but also by the standard deviation to evaluate the surface uniformity and flatness. Through magnetic field simulation and experiments, it is proved that the bottom groove of the magnetic pole helps to make the magnetic particle distribution more uniform in the processing area, which can effectively improve the surface quality. In addition, through experiments, changing the trajectory of the magnetic brush can also effectively improve the surface flatness of the finished surface.

In order to improve the machining efficiency of a traditional plane magnetic abrasive finishing (MAF) process, the MAF combined with an electrolytic process (EMAF) was proposed. Because the relation among the magnetic field, the electric field, and the flow field of the electrolyte is very complicated in the EMAF process, the machining mechanism has not yet been investigated clearly. In this paper, the mechanism of the EMAF process was investigated, and mainly discusses the influencing factors of finishing stability and surface quality. First, a set of current measurements and recording devices was designed to investigate the current changes during the finishing process. The measured current value curve was used to evaluate the processing status. Then, validation experiments were performed; the influence of the particle size and supply amount of magnetic particles on processing was observed. Experimental results show that it was clarified that the optimal experimental conditions existed, and the best results were obtained when using the electrolytic iron powder (330 μm in mean diameter) and a supply amount of 0.6 g.

The magnetic abrasive finishing (MAF) process is an ultra-precision surface finishing technology. In order to further improve the finishing efficiency and continuity, a magnetic abrasive finishing process using the circulatory system to renew magnetic abrasive slurry was proposed. This study investigated the mechanism of the compound magnetic finishing fluid in the process using the conveyor belt as the carrier to complete the circulation and finishing through simulation and theoretical analysis. The influence of the different distribution states of the magnetic finishing fluid in the conveyor belt and the finishing area on the finishing characteristics is observed and analyzed, in addition to a series of experiments to explore the feasibility of finishing polychlorotrifluoroethylene resin plate through this process. Experimental results show that as the working gap decreases, the distribution width of compound magnetic finishing fluid on the conveyor belt becomes larger, and the distribution of the points of action on the workpiece in the finishing area is significantly different and the area increases, and obtains a higher finishing force and finishing efficiency. In this study, the surface roughness of polychlorotrifluoroethylene resin plate was improved from 274 nm Ra to 34 nm Ra within 15 min.

In this paper, we propose a new plane magnetic abrasive finishing method, applicable to planes, that uses the alternating magnetic fields to solve problems such as the easy deformation and poor recovery of a magnetic brush in conventional magnetic abrasive finishing method. Compared with the magnetic brush used in conventional magnetic abrasive finishing, that in the new method can stably shape a workpiece under an alternating magnetic field. To determine the optimal finishing parameters, we focused on studying the effects of spindle rotational speed, size of diamond particle, and frequency of alternating magnetic field on the finishing surface. Then, according to the obtained optimal finishing parameters, multi-stage finishing experiments were performed with the new method. The results show that surface roughness can be improved from 230 nm Ra to 19 nm Ra in 60 min with the proposed method.

A magnetic abrasive nano-polishing process using low-frequency alternating magnetic field was developed for micro-grooves surface in this study. And by using alternating magnetic force produced by low-frequency (3 Hz) alternating magnetic field to make magnetic cluster generates a cyclical fluctuation of up and down, and then promotes the abrasives into micro-groove surface. A set of experimental devices were designed to investigate the effect of magnetic pole shape on magnetic field distribution and finishing characteristics. Final experiments were performed on glass and alloy steel specimens to examine the polishing performance for micro-groove surface. The glass initial surface roughness (Ra) of 123.38 nm, 130.71 nm, 136.08 nm, and 129.39 nm decreased respectively to 55.18 nm, 50.92 nm, 65.62 nm, and 62.42 nm and the groove surfaces obtained obvious improvement by this process. The surface roughness (Ra) of alloy steel is reduced as low as 68.70 nm from 192.48 nm, and the burr of edge and groove surface was removed effectively after 20-min polishing. It is demonstrated that this process is effective for deburring and improving micro-groove surface quality.

In order to achieve the finishing of complex microsurface, the magnetic abrasive finishing process using alternating magnetic field was proposed. In this paper, the mechanism of the magnetic abrasive finishing process using alternating magnetic field was investigated. At the same time, the influence of magnetic particle size and magnetic field frequency on magnetic cluster changes was observed and the relationship between finishing force and alternating magnetic field was analyzed. In addition, the feasibility of ultraprecision finishing of 5052 aluminum alloy plate through this process was studied, and the influence of relevant process parameters on the finishing characteristics was analyzed. The experimental results show that the surface roughness of 5052 aluminum alloy plate improved from 318 to 3 nm Ra in 15 min.

The critical influencing factors of the interface bonding properties of concrete-filled steel tubes (CFSTs) under fire and postfire conditions are analyzed. This paper analyzes and summarizes the existing research related to the bonding performance of CFST interfaces under fire and postfire conditions at home and abroad, which includes the bonding mechanism of CFST structures, the bonding strength of CFSTs during and after fire exposure, and the main factors influencing bond strength. The analysis results indicate that the temperature has noticeable influences on the bond strength of a CFST during and after fire exposure. The bond strengths of the specimens are reduced more severely under high-temperature conditions than after high-temperature cooling. Shear connectors can significantly improve the bonding performance of CFSTs and effectively reduce the relative slip between steel tubes and concrete. The paper concludes with an analysis of the deficiencies in bond-slip research on the bonding properties of the CFST interface during and after fire exposure and future research directions. First, we can study the use of new technologies and materials to solve the problem of bonding and slipping of CFSTs during and after fire exposure. Second, we can perform extensive experimental research and theoretical simulation analysis to enrich the research in this field, which can provide a reference for engineering practice.

The magnetic abrasive finishing (MAF) process is an ultra-precision surface finishing process. In order to further improve the finishing efficiency and surface quality, the MAF process using an alternating magnetic field was proposed in the previous research, and it was proven that the alternating magnetic field has advantages compared with the static magnetic field. In order to further develop the process, this study investigated the effect on finishing characteristics when the alternating current waveform is a square wave. The difference between the fluctuation behavior of the magnetic cluster in two alternating magnetic fields (sine wave and square wave) is observed and analyzed. Through analysis, it can be concluded that the use of a square wave can make the magnetic cluster fluctuate faster, and as the size of the magnetic particles decreases, the difference between the magnetic cluster fluctuation speed of the two waveforms is greater. The experimental results show that the surface roughness of SUS304 stainless steel plate improves from 328 nm Ra to 14 nm Ra within 40 min.

In order to achieve the precision machining of the alumina ceramic surface, we propose surface finishing of alumina ceramic by the magnetic abrasive finishing (MAF) process using low-frequency alternating magnetic field. In previous studies, the effects of important process parameters on finishing force and finishing characteristics were investigated when the magnetic particle diameter was 6 and 30 μm. Due to the higher hardness of alumina ceramics, greater finishing force is needed, so we studied the effect of magnetic particle diameter and alternating magnetic field frequency on the finishing force. In order to determine the best experimental conditions, we study the effect of important process parameters on the finishing characteristics. The experimental results prove that the surface finishing of alumina ceramic can be achieved. The surface roughness of the alumina ceramic plate can be improved from 244.6 nm Ra to 106.3 nm Ra.

On the basis of ordinary plane magnetic abrasive finishing, a finishing method is proposed that can improve the flatness of a plane workpiece. In this method, the feed speed is varied during finishing according to the profile curve of the initial surface and the material removal efficiency, to control the effective finishing time in different areas and thereby improve the surface flatness. A small magnetic pole with an end face diameter of 1 mm is designed, and a ferromagnetic plate is placed under the workpiece to improve the uniformity of the magnetic field distribution near the magnetic pole. An experiment on an A5052 aluminum alloy plate workpiece shows that after 60 min of finishing using the proposed method, the extreme difference of the workpiece surface can be reduced from 14.317 μm to 2.18 μm, and the standard deviation can be reduced from 3.322 μm to 0.417 μm. At the same time, according to the measurement results, a similar flatness can be achieved at different positions on the finishing area. Thus, the proposed variable-speed finishing method leads to obvious improvements in flatness.

This research proposes an effective plane magnetic abrasive finishing (MAF) process which was combined with electrolytic process in order to improve machining efficiency of traditional plane MAF process. The new plane finishing process can make surface of workpiece to be planarized and softened through formed passive films from electrolytic process. Meanwhile, the passive films are removed by magnetic brush-generated mechanical processing force to achieve efficient precision machining. This finishing process is called electrolytic magnetic abrasive finishing (EMAF). In this research, we have developed a novel machining tool of compound magnetic poles and electrodes, which is able to achieve two different processes. The SUS304 stainless steel plane is used as workpiece. In order to select electrolytic finishing time for EMAF process, the investigation of electrolytic process has been carried out before EMAF process. Then, the comparative experiments of EMAF process and MAF process have been conducted in order to investigate the effect of EMAF process. The experimental results show that EMAF process can a little obtain higher quality surface, and machining efficiency is improved by about 50%, which compared with that of traditional plane MAF process. Furthermore, the surface roughness can be reduced to 30.94 nm R a from original roughness of 393.08 nm R a in 40 min by the EMAF process.

With the technical development of computer hardware and software, digitalization is a trend in large-scale complex systems such as nuclear power plants (NPPs). It changes the way main control room (MCR) operators interact with systems. Faced with these technical changes, operators need to continue improving their situation assessment (SA) reliability level. In addition to evaluate operators’ SA reliability, managers and shift supervisors also want to forecast their SA reliability level. There have been many studies with respect to operators’ SA, but most of them are static analysis method and cannot be applied to predict operators’ SA reliability. So, on the basis of different forecasting approaches and observation data, how to predict the operators’ SA reliability level has became a problem that many analyst interest in. In this paper, first we identified the influence factors associated with SA reliability, and then we developed the SA reliability model, finally we proposed a reliability forecasting model by integrating time series forecasting method with dynamic network model (DNM). Our experiment verification focused on steam generator tube rupture (SGTR) event, using the forecasting model, we demonstrated how to predict operators’ SA reliability during the course, and the prediction results are consistent with measurement results.

In order to improve the finishing efficiency of traditional plane magnetic abrasive finishing (MAF), we have previously proposed an effective plane MAF process combined with an electrolytic process and developed a special compound machining tool for the electrolytic magnetic abrasive finishing (EMAF). In this research, the EMAF process is divided into two finishing steps. The first finishing step is the EMAF step, and a single MAF step constitutes the second finishing step. The machinability of SUS304 material can be improved through the formation of passive films from the electrolytic process in the EMAF step. Meanwhile, the passive films can be rapidly and easily removed by friction between the magnetic particles and the workpiece-generated mechanical machining force. Thus, the surface finishing efficiency can be greatly improved. Compared with a dedicated MAF machining tool or a dedicated electrolytic machining tool, this special compound machining tool can synchronously achieve MAF and electrolytic processes to make the processing more convenient. This study focuses on exploring mechanical finishing characteristics of the special compound machining tool through MAF experiments. Additionally, EMAF experiments are conducted under the optimal mechanical finishing conditions. The experimental results of the EMAF process show that the surface roughness Ra can be reduced to less than 30 nm at the 4-min EMAF step, and it can be further reduced to 20 nm at the 10-min MAF step.

We proposed a new ultra-precision magnetic abrasive finishing (MAF) process using low frequency alternating magnetic field in this paper. Magnetic cluster themselves may produce the up and down movement change under alternating magnetic force. The movement may not only promote the dispersion of micro-magnetic particles, but also improve stirring effect and cross-cutting effects of the abrasives, achieving circulation and update to ensure the stability of grinding tools. This process is considered to be able to efficiently apply in ultra-precision finishing of plane and complicated micro-surfaces. In this study, we investigated the effects of alternating magnetic field on magnetic field distribution, finishing force and abrasive behavior. Furthermore, a set of experimental devices have been designed for finishing SUS304 stainless steel plate. The present work is aimed at understanding finishing particularity of this process and studying impacts of important process parameters namely grinding fluid, rotational speed of magnetic pole, current frequency on change in finish surface and material removal. Experimental results indicate that the process can realize ultra-precision finishing of plane by using oily grinding fluid. In the present research, the surface roughness of SUS304 stainless steel plate was improved from 240.24 nm to 4.38 nm by this process.

To improve polishing efficiency of traditional magnetic abrasive finishing (MAF) for polishing metal material, we proposed an effective MAF which combined with electrolytic process. The hardness of workpiece surface can be reduced since passive films are generated by electrolytic action. Simultaneously, the generated passive films can be easily removed by friction which is generated between magnetic particles and workpiece. Therefore, electrolytic magnetic abrasive finishing (EMAF) can significantly minimise the surface roughness in a shorter finishing time. In this study, we focused on researching the combination of the first finishing step (EMAF step) time and second finishing step (MAF step) time. The optimal experimental results showed that the surface roughness Ra can be reduced to less than 30 nm at 4 min EMAF step, the surface roughness Ra can be reduced to 20 nm at 10 min MAF step. Furthermore, we also analysed the change in size of mixed magnetic abrasive.

Two coordination polymers, {[Mn(1,10-phen)2(3,4-H2bptc)] · (H2O)}2 n (1) and {[Co2(1,10-phen)(3,4-bptc)(H2O)2] · H2O} n (2) (3,4-H4bptc = 3,3′,4,4′-biphenyltetracarboxylic acid, 1,10-phen = 1,10-phenanthroline), have been prepared and structurally characterized. In both compounds, 3,4-H2bptc2– and 3,4-bptc4− exhibit different coordination modes and lead to various architectures. Compound 1 displays 1-D zigzag chains constructed with hydrogen bonds. Compound 2 exhibits a 2-D layer constructed from bpta4− between the dinuclear Co(II) units. The thermal stabilities and magnetic properties are also reported. In addition, 1 was explored as a luminescent material. The carboxylic oxygen atoms act as H-bond acceptors and donors forming a 1-D ladder-like arrangement.

Two types of novel lanthanide complexes with the 6-hydroxynicotinic acid (OHnicH) {[Ln(OHnic)(Onic)(H2O)5·(OHnicH)]·H2O}n [Ln = La(1), Ce(2), Gd(3)] and {[Ln(OHnic)3(H2O)]·3H2O}n [Ln = La(4), Pr(5)] have been synthesized and characterized by elemental analyses, IR spectra, UV absorption spectra and single crystal X-ray diffraction. The structures of the as-prepared complexes vary with the different coordination modes of the ligands. In complexes 1–3, the adjacent metal centers are linked by the chelating-bridging tridentate modes of the ligands to form 1D chains; while in 4 and 5, the adjacent metal ions are bridged by the ligands in the chelating-bridging bidentate modes to form dinuclear units, then linked into 1D chains through the ligands in the bridging bidentate modes, and further linked to form 2D plane structures via the bridging tridentate modes of the ligands. Thermostabilities and luminescent properties of the complexes have been discussed in detail.