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Objective: To optimize the operating parameters of wheat milling in roller mill I skin mill to reduce the energy consumption of milling. Methods: Using EDEM discrete element simulation software, Box-Behnken test was designed for key milling factors such as roll pitch, feeding amount, rotational speed and rotational speed ratio to investigate the relationship between operating parameters and milling power. Results: The significance rankings of the effects on the toothed roll crushing power were, in order, speed ratio, roll pitch, feed volume, speed ratio quadratic term, roll pitch quadratic term, interaction of roll pitch and speed ratio, interaction of feed volume and speed ratio, and interaction of roll pitch and feed volume. According to the different requirements of the I-skin mill, the optimal parameter combinations were obtained: the finer powder output with a rolling pitch of 0.67 mm, a feeding amount of 803.60 kg/（cm·d）, a fast roller speed of 537.68 r/min, and a rotational speed ratio of 2.64, and the coarser powder output with the optimal low-power consumption of 0.79 mm, a feeding amount of 803.83 kg/（cm·d）, a fast roller speed of 576.08 r/min, and a rotational speed ratio of 2.23. Conclusion: The error between the simulation results and the measured results is within a reasonable range, and the established discrete element milling model can be used for power prediction in wheat milling.

Objective: To achieve surface wear life prediction of abrasive blast rollers of grinding machines. Methods: The wear images of the grinding roller surface were acquired by the built image acquisition system, and the texture parameters such as second order moments, entropy value, contrast and correlation in the wear cycle of the grinding roller were obtained based on the grey scale co-generation matrix algorithm, and the obtained texture feature parameters were input into the constructed PSO-based LS-SVM algorithm model to finally predict the wear life of the blast roller. Results: The particle swarm algorithm could optimize the penalty factor and kernel parameters of LS-SVM well, and the PSO-LS-SVM algorithm was far superior to the LS-SVM algorithm model. The wear state of the blast roller surface of the mill could be accurately identified using the PSO-LS-SVM algorithm. Conclusion: The system can accurately predict the service life of the blast rollers.

The complex hydrogeological structure and abundant karst water in the carbonate rock distribution area in the Jinshajiang fault zone's middle section are essential threats to engineering safety. Based on karst landform and hydrogeological investigations, the article presents the karst development characteristics in the Jinshajiang fault zone's middle section, and analyzes the recharge source, runoff process, and discharge characteristics of karst water using the methods of hydrochemical and new isotopic dating and tracing. The results show that structures control the spatial distribution of karst and the groundwater circulation in the study area. There are mainly three elevation-level karst development zones in the vertical direction. The development time of the second elevation-level karst is from the late Miocene to the late Pleistocene, and the top of the third elevation-level karst is from the Pliocene to the late Pleistocene. The karst water recharge area is at an elevation of 4400~4600 m. The primary recharge sources are atmospheric precipitation and glacial lake water. The 228Ra/226Ra data in the water shows that it is difficult for water sources under the control of a non-fixed-curvature fault to form recharge across the affected area of the fault. The karst water circulates fast, the 85Kr age of the karst spring is < 15 a, and there is basically no older groundwater mixing. Carbonate rock dissolution and cation exchange are not sufficient during groundwater runoff. In the engineering project, the spatial distribution of karst water runoff channels under the control of active faults, the influence of high-water-pressure and the threat of geological disasters caused by special weather conditions should be fully considered.

Abstract Backgrounds In the face of the new environment, different individuals have different reactions. Those who have good adaptability constantly establish individual self-efficacy through making friends and completing their studies, thus forming a good dependency with the university environment. However, individuals with poor ability to adapt to the new environment will have some bad phenomena, such as truancy, weariness and self denial. As a result, the students’ adaptations of to the growth environment where in universities are the important topics in recent years. Methods Present study introduces irrational beliefs to investigate the effects of parenting mode on maladaptation of university students. The questionnaires based on simplified parenting mode (Chinese), irrational belief and adaptability were administered in a survey of 510 university students in Zhanjiang on October, 2021, the list of students of Guangdong Ocean University is taken as the sampling frame and determined by random sampling. Parenting mode was used as the independent variable, while the emotionally warm, overprotective and rejecting types were used as the indices. Further, the irrational beliefs including summary comments, awful beliefs and low tolerance to setbacks as well as maladaptation were included in the mediation model for analysis. Results The results showed that the rejection parenting mode was negatively related with absolute requirements (r = − 0.143), and learning motivation (r = − 0.157), interpersonal adaptation (r = − 0.283) and physical and psychological adjustment (r = − 0.083). Overprotection was negatively correlated with absolute requirements (r = − 0.042) and interpersonal adaptation (r = − 0.042). The mediating effect of irrational beliefs (low tolerance to setbacks, awful beliefs and absolute requirements), the lower and upper limits of Bootstrap confidence interval were 0.135 and 0.461, respectively, excluding 0, which indicated that the mediating effect is true. Conclusion Through the analysis of the data, this study believes that irrational beliefs such as low tolerance to setbacks, awful beliefs and absolute requirements mediate the effects on school adjustment. Negative parenting modes such as overprotection and rejection inculcate irrational beliefs, resulting in maladaptation of university students.

Measuring the exact technology complementarity between different institutions is necessary to obtain complementary technology resources for R&D cooperation.

There are many advantages of reasonably determining the affected zone and its construction sequence for the multiline parallel pipe-jacking construction, such as convenient to reasonably arrange the pipeline section distribution mode, reducing the construction safety risk, and construction difficulty. Combined with the engineering construction practice of the multiline parallel pipe-jacking project for the north city drainage and flood control project through Chu River in Hefei, the strength reduction method has been utilized to study the surrounding stratum FOS for the pipe-jacking construction unloading under different overburden thickness Hs, different clear distance D, and different river water depth Hw in this paper. The formula of the minimum critical overburden thickness Hsmin and the minimum critical clear distance Dmin of the surrounding stratum self-stability during pipe-jacking construction unloading have been derived. The division method of the affected zone for the multiline parallel river-crossing pipe-jacking construction which behaves as the mutual influence nonself-stability zone, the mutual influence self-stability zone, and the no mutual influence self-stability zone has been proposed. For further discussion, the construction sequence of the multiline parallel river-crossing pipe jacking has been studied.

Objective To investigate the clinical characteristics of right atrial tumors and to analyze the experience and efficacy of surgical treatment. Methods The clinical data of 64 patients (37 females and 27 males, at a mean age of 47.0±16.4 years) with right atrial tumors admitted to our hospital from January 2009 to January 2021 were retrospectively collected and analyzed. The clinical features, surgery techniques adopted, postoperative complications and metastatic recurrence of patients were summarized in detail. Results Among all the 64 cases, benign tumors accounted for 78.1% and malignant tumors for 21.9%; while among the 53 patients who underwent surgical treatment, 83.0% of the tumors were benign and 17.0% malignant. The top 3 most common clinical symptoms involved fatigue, chest tightness and pain or precordial discomfort, and facial or lower limbs edema. And the most frequent preoperative complications were atrial fibrillation/flutter, followed by pulmonary embolism. Moreover, the overall in-hospital mortality rate was 3.1%, and the postoperative mortality rate 1.9%. Among the patients with benign tumors, 1 had residual tumor thrombus at the distal end of inferior vena cava, 1 occurred arrhythmia requiring surgical intervention, 3 developed moderate to severe tricuspid regurgitation, and 2 had metastatic recurrences. In the patients with malignant tumors who received surgery, 1 died early postoperatively, 6 developed metastatic recurrences between half a month and 2 years plus 7 months, and 2 cases were lost during follow-up. Conclusion Primary benign tumor is the major type of right atrial tumors. Surgical treatment for benign tumors is safe and effective, even in recurrent cases. Selective surgical treatment for malignant tumors can improve hemodynamics and clinical symptoms, though the overall prognosis tends to be poor.

Objective To summarize the clinical characteristics and surgical treatment experience of congenital heart disease complicated with infective endocarditis. Methods The clinical data including perioperative management and surgical approaches of 83 cases of congenital heart disease with active infective endocarditis admitted to the Department of Cardiovascular Surgery of our hospital between January 2015 and December 2019 were collected and retrospectively analyzed. Results Among the 83 patients enrolled, early postoperative death occurred in 2 cases, with an in-hospital mortality rate of 2.4%, 2 cases were discharged voluntarily due to abandonment by their family member, and the remaining 79 patients recovered well. The 2 most common postoperative complications were heart failure (16.9%) and grade Ⅲ atrioventricular block (8.4%). During the follow-up of 3 months to 5 years, residual shunt occurred in 4 cases, with 2 of them being confirmed closed spontaneously, and peak prosthetic velocity and mean gradient increase occurred in 6 cases. No endocarditis recurred and none of the above so far needed surgical reintervention. Conclusion Early detection and standard anti-infection treatment, multidisciplinary team cooperation, appropriate timing of surgery, and retinal surgical procedure are the key factors to achieve good clinical efficacy.

Objective To evaluate the clinical efficiency of intra-aortic balloon pump (IABP) in the perioperative period for the patients undergoing heart valve replacement by propensity score matching (PSM). Methods During January 2014 to December 2016, 43 patients treated with IABP in perioperative period in our institute were recruited and assigned into observation group. They were 21 males and 22 females, and at an average age of 52.5±9.8 (33~73) years. Another 43 patients (20 males and 23 females, aged 31~72 years, averagely 52.3±11.7 years) who underwent valve replacement but not IABP were selected from 1 487 cases of heart valve replacement patients in 2013 by PSM to balance intraoperative baseline data. The perioperative mortality, duration of assisted ventilation, length of ICU stay and incidences of postoperative complications were analyzed and compared between the 2 groups. Results There were no statistical differences in perioperative mortality [16.3% (7/43) vs 11.6% (5/43), P=0.137] and cases needing dialysis [7% (3/43) vs 14% (6/43), P=0.062] between the 2 groups. The observation group had statistically shorter time of endotracheal intubation (66.02±31.2 vs 79.27±17.1 h, P < 0.05) and lower incidence of low cardiac output syndrome (4.7% vs 37.2%, P < 0.05) than the other group. Conclusion IABP decreases the incidence rates of postoperative complications, but has no effect on the mortality in the patients undergoing heart valve replacement

Generally, two topics with vastly different terminology probably indicate different implied concepts. However, these topics themselves might share common references (bibliographic coupling), which suggest the underlying joint concept. Therefore, searching for these joint concepts in different topics would be of scientific interest. Previous studies have measured the similarity between topics based on comparison of the topics' word probability distributions. In contrast, this paper presents an approach for measuring the similarity between topics based on the bibliographic coupling. Besides, the similarity is independent of the topic's word probability distributions generated by a Latent Dirichlet Allocation (LDA) model. The proposed approach was evaluated using its counterpart (intra-topic similarity), baseline topic similarity matrices, and cosine measure. The method was exampled on brain cancer patents. A cross-topic similarity network of eight topics showcases 28 cross-topic pairs to profile which topics were associated with particular topics. Interestingly, some of the 28 combinations may be of scientific interest. For instance, the findings of the top five cross-topic pairs suggest that “growth of cancer cells” and “imbalances in the hormones” have common knowledge sources with the highest similarity value. These two entirely different concepts may suggest some common causative factors within the field. We believe that finding such an association between unrelated innovative inventions across various industries may help public and private research units in planning research direction and serve as a reference for future research.

By using the samples of fine sand in Shanghai’s seventh layer, creep tests were performed to investigate the deformation characteristics of fine sand under different groundwater table change. It was revealed that the creep of fine sand is closely related to groundwater table change: when the effective force caused by groundwater table change is smaller than pre-consolidation force, the deformation is mainly elastic. When effective force caused by groundwater table change is bigger than pre-consolidation force, the compression deformation is large and the rebound is small; and the deformation is mainly viscoelastic plastic when equal to pre-consolidation stress. Through the scanning electron microscope (SEM) analysis it was found that creep of fine sand is dominated by the slip of particles, not by the breaking of particles. And the fine sand particles are squeezed under the load induced by the groundwater table change, and the particles slide along the indirect contact surface of the particles, resulting in the continuous adjustment of position and relative displacement. Mercury injection test shows that the pore size distribution of fine sand has little change before and after the test.