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Objective: In the treatment of resectable pancreatic cancer, adjuvant chemotherapy is viewed as essential. However, it is yet unclear how well adjuvant chemotherapy works at different illness stages. This study aims to investigate the efficacy of adjuvant chemotherapy in various pancreatic cancer stages. Materials and methods: Patients with pancreatic cancer who underwent surgical intervention at Sun Yat-sen University Cancer Center between January 2018 and January 2021 were included in this retrospective analysis. Results: 168 patients were divided into two groups: the group receiving adjuvant chemotherapy (AC) and the group receiving independent surgery (no-AC). Survival analysis reveals that among stage I patients, the AC group demonstrates significant superiority over the no-AC group in terms of recurrence-free survival (RFS) and overall survival (OS) (P = 0.0028; P = 0.022). While there was no discernible difference in RFS between the AC and no-AC groups for patients with stage II illness (P = 0.69), the AC group significantly outperformed the no-AC group in terms of OS (P = 0.047). There was no discernible difference in RFS or OS between the AC and no-AC groups for patients with stage III pancreatic cancer (P = 0.40 and P = 0.20, respectively). Conclusions: The administration of adjuvant chemotherapy has been shown to improve the prognosis of patients diagnosed with stage I and II pancreatic cancer. However, its efficacy is limited in individuals with stage III pancreatic cancer. Therefore, there is an urgent need to investigate and develop more effective therapeutic options for patients in the advanced stage.

The role of surgery in the treatment of metastatic pancreatic neuroendocrine tumors (PNETs) was controversial. The objectives of this study were to illustrate the impact of surgery in improving the prognosis of patients with metastatic PNETs and build nomograms to predict overall survival (OS) and cancer-specific survival (CSS) based on a large population-based cohort.Patients diagnosed with metastatic PNETs between 2004 and 2015 from the Surveillance, Epidemiology, and End Results (SEER) database were retrospectively collected. Nomograms for estimating OS and CSS were established based on Cox regression model and Fine and Grey’s model. The precision of the nomograms was evaluated and compared using concordance index (C-index) and the area under receiver operating characteristic (ROC) curve (AUC).The study cohort included 1966 patients with metastatic PNETs. It was shown that the surgery provided survival benefit for all groups of patients with metastatic PNETs. In the whole study cohort, 1-, 2- and 3-year OS and CSS were 51.5, 37.1 and 29.4% and 53.0, 38.9 and 31.1%, respectively. The established nomograms were well calibrated, and had good discriminative ability, with C-indexes of 0.773 for OS prediction and 0.774 for CSS prediction.Patients with metastatic PNETs could benefit from surgery when the surgery tolerance was acceptable. The established nomograms could stratify patients who were categorized as tumor-node-metastasis (TNM) IV stage into groups with diverse prognoses, showing better discrimination and calibration of the established nomograms, compared with 8th TNM stage system in predicting OS and CSS for patients with metastatic PNETs.

Postpartum hemorrhage (PPH) is one of the most adverse obstetric outcomes. Our aim is to detect the risks of multilevel PPH in different cesarean section (CS) groups [including nulliparous CS with indications, nulliparous CS without indications, repeat cesarean (RC), vaginal birth after cesarean (VBAC), cesarean after vaginal birth (CAVB)]. We conducted a retrospective cohort study, and the data on 127 145 women collected from January 2014 to May 2016 and from 35 tertiary hospitals in Shanxi province, China, were reviewed. Based on the measuring results of PPH, an ordered logistic regression model was used to analyze the adjusted PPH risks for each of the CS groups, and comparisons were drawn between them. Finally, a total of 99 066 nulliparous (77.92%) and 28 079 multiparous (22.08%) women were observed. The number of CS cases was 61 117, and the rate for CS was 48.07%. A total of 10 029 women did not show indications for CS and accounted for 16.41% of the CS parturient, whereas 9103 women underwent a repeated cesarean, with a CS frequency of 14.89%. The number of VBAC cases was 989, whose rate was 9.88% in prior CS women. The number (proportions) of PPH was 3658 (2.88%) in LI (PPH volume: ≥900 and <1500 mL), 520 (0.41%) in 12 (PPH volume: >1500 and <2100 mL), and 201 (0.16%) in L3 (PPH volume: ≥2100 mL). The Ln (n=l, 2,3, etc.) represented the increasing order of PPH severity. In the adjusted results, compared with spontaneous vaginal delivery (SVD) as the reference group, in the adjusted result for nulliparous, there was a decreased PPH risk in CS with indications (OR: 2.32; CI: 2.04–2.62), which was lower than that of CS without indications (OR: 2.50; CI: 2.01–2.96). The highest PPH risk in all subgroups (i.e. nulliparous and multiparous groups) was observed in the RC (OR: 3.61; CI: 3.16–4.17), which was nearly twice higher than that of the VBAC (OR: 1.82; CI: 1.33–2.52). CAVB (OR: 1.03; CI: 0.65–1.62) showed no significant difference with the reference group. Thus, we deemed that CS should be avoided in nulliparous pregnancies unless indicated, to prevent or reduce the rates for the use of RC or VBAC which are high risks of severe PPH to the parturient women.

China implemented the public hospital reform in 2012. This study utilized bootstrapping data envelopment analysis (DEA) to evaluate the technical efficiency (TE) and productivity of county public hospitals in Eastern, Central, and Western China after the 2012 public hospital reform. Data from 127 county public hospitals (39, 45, and 43 in Eastern, Central, and Western China, respectively) were collected during 2012–2015. Changes of TE and productivity over time were estimated by bootstrapping DEA and bootstrapping Malmquist. The disparities in TE and productivity among public hospitals in the three regions of China were compared by Kruskal–Wallis Htest and Mann–Whitney Utest. The average bias-corrected TE values for the four-year period were 0.6442, 0.5785, 0.6099, and 0.6094 in Eastern, Central, and Western China, and the entire country respectively, with average non-technical efficiency, low pure technical efficiency (PTE), and high scale efficiency found. Productivity increased by 8.12%, 0.25%, 12.11%, and 11.58% in China and its three regions during 2012–2015, and such increase in productivity resulted from progressive technological changes by 16.42%, 6.32%, 21.08%, and 21.42%, respectively. The TE and PTE of the county hospitals significantly differed among the three regions of China. Eastern and Western China showed significantly higher TE and PTE than Central China. More than 60% of county public hospitals in China and its three areas operated at decreasing return scales. There was a considerable space for TE improvement in county hospitals in China and its three regions. During 2012–2015, the hospitals experienced progressive productivity; however, the PTE changed adversely. Moreover, Central China continuously achieved a significantly lower efficiency score than Eastern and Western China. Decision makers and administrators in China should identify the causes of the observed inefficiencies and take appropriate measures to increase the efficiency of county public hospitals in the three areas of China, especially in Central China.

Deformation allocation has significant effects on the process of multi-pass conventional spinning, especially for the curvilinear generatrix parts. Three different patterns of deformation allocation for curvilinear generatrix parts, including equal max deformation, equal arc length, and equal axial distance, are proposed and defined. Roller path profiles are designed based on them respectively. A 3D elastic-plastic finite element model is developed to investigate the effects of deformation allocation on forming quality and efficiency of the multi-pass spinning of curvilinear generatrix parts, based on the designed paths. The results show that a reasonable deformation allocation in each pass can improve the efficiency of the process effectively. The equal max deformation pattern can lead to better wall thickness distribution and forming efficiency. However, the fittability of it is poorer, compared with the others. This phenomenon is more significant with the increase of pass number.

Nowadays, composite material is more and more popular mainly because of its low density and high strength. This paper focuses on experimental research of coarse milling process of carbon fiber reinforced carbon matrix composite (C/C composite) in low spindle speed and large milling depth. The milling force prediction model for milling of composite using the end milling cutter is built by orthogonal experiment. Experiment test shows that the results predicted by the proposed model are in well agreement with measured ones and the milling force increases with the increment of feed per tooth, milling depth and milling width, and the effect of milling speed on milling force is not very obvious. In addition, machining accuracy and quality of machined surface is difficult to satisfactory, because of the existence of the substrate lacunas and carbon fibers in C/C composite, by using the existing ordinary material surface integrity evaluation method.

The performance of arc welding power source is an important factor that affecting the use safe and welding quality, so a special equipment for the factory testing is required. The test equipment for arc welding power supply is master-slave structure, and includes hardware and software system. Hardware system complete data acquisition and information display, controlled by embedded micro-controller. The software system complete a graphical user interface programs and collection procedures, developed in the embedded Linux environment. The device enables the automated testing of the welding power source, such as loading, data transmission, reflecting a good man-machine interactivity. The system will be applied to the factory inspection of welding power source, to assess its the quality and performance through tested parameters.

The blade and blisk manufacturing includes polishing process when the surface roughness and size requirement of profile are disqualified after milling process. This polishing process is mainly carried out manually by skilled workers or NC machines. However, the existing polishing technology always leads to surface quality instability and inconsistency because of the complex free-form surface of blade and blisk. Therefore, in this paper, based on the research of polishing requirements and methods of blade and blisk, an automatic 6-axis polishing machine was proposed in order to enhance surface quality. And then, a polishing mechanism was designed using flexible technique to make the polishing tool accommodate surface waviness which was produced in milling process. In addition, the working principle and control method of flexible polishing mechanism were studied. Finally, the polishing test results of blade and blisk showed that the profile error was about 0.06mm and the surface roughness was less than Ra0.4 after automatic polishing. Compared with the manual polishing process, the automatic polishing technology not only increased the polishing efficiency and quality stability, but also reduced labor intensity largely.

Previous studies have shown that health insurance type affects patient outcomes, but empirical research on the effect of health insurance on quality and efficiency of care in China is scarce. This study aimed to determine whether there are health insurance-related differences in hospital care for acute myocardial infraction.

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Chinese county hospitals have substantially enlarged their scale and service volume since the new health-care reform in 2009. In the context of scale expansion, continuously efficient operations are important considerations. In this study, we aimed to estimate the efficiency of Chinese county hospitals after such expansion and to establish whether and how efficiency is affected by various factors.