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In order to reveal the influence of starting acceleration on starting process of a pump as turbine system, this paper carries out a numerical calculation of the three-dimensional viscous unsteady flow of pump as turbine circulating piping system under three starting acceleration conditions, and obtains the external and internal flow characteristics of each overflow component during the starting process, and also analyzes the energy loss of each component in the piping system in depth with the help of entropy production method and Q criterion method. The results show that during system start-up, the flow rate and outlet static pressure curves of the pump as turbine are hysteresis relative to the rotational speed, the head curve is similar to a linear rise during slow and medium speed start-up, while it shows a parabolic rise during rapid start-up, the entropy production and vorticity in the impeller domain of the pump as turbine are mainly distributed between the blades, and the distribution decreases during start-up. In addition, the pump similarity law does not apply to the performance prediction during the transient start of the pump as turbine.

Gastric cancer is a tumor type characterized by lymph node metastasis and the invasion of local tissues. There is thus a critical need to clarify the molecular mechanisms governing gastric cancer onset and progression to guide the treatment of this disease. Long non-coding RNAs and mRNA expression profiles associated with early and local advanced gastric cancer were examined through microarray analyses, with GO and KEGG analyses being employed as a means of exploring the functional roles of those long non-coding RNAs and mRNAs that were differentially expressed in gastric cancer. In total, 1005 and 1831 lncRNAs and mRNAs, respectively, were found to be differentially expressed between early and local advanced gastric cancer. GO and KEGG analyses revealed several pathways and processes that were dysregulated, including the RNA transport, ECM-receptor interaction, and mRNA splicing pathways. In co-expression networks, E2F1, E2F4, and STAT2 were identified as key transcriptional regulators of these processes. Moreover, thrombospondin-2 was confirmed as being expressed at high levels in more advanced gastric cancer by both the GEO and TCGA databases. RNA-sequencing analyses of SGC-790 cells transfected to express thrombospondin-2 further revealed this gene to enhance NF-kB and TNF pathway signaling activity. These results offer insight into gastric cancer-related regulatory networks and suggest thrombospondin-2 to be an important oncogene that drives the progression of this deadly cancer type.

Background:Since initially detected in late December 2019, the novel coronavirus disease 2019 (COVID-19) outbreak rapidly swept the world, which has profoundly affected healthcare system and clinical practice in the management of gastrointestinal diseases.Objectives:We aimed to evaluate the impact of COVID-19 pandemic on the pattern of hospital admissions and healthcare services for acute pancreatitis (AP).Design:We conducted a retrospective observational cohort study using the anonymized electronic medical records.Methods:This single-center, retrospective observational study from a regional medical center in the northeast of China included all consecutively admitted patients with AP from 23 January to 10 June 2020 (during the COVID-19 outbreak in Harbin), compared with the equivalent period of the previous year, in terms of demographics, clinical characteristics, and in-hospital outcomes.Results:In this article, we observed a reduction in AP admissions after the beginning of COVID-19 outbreak. With the prolonged time from symptom onset to hospitalization [32.0 (22.0–72.0) versus 18.0 (12.0–24.0) h; p Conclusion:This study preliminarily demonstrated the descending trend and delay in hospital presentations for AP during the outbreak of COVID-19. Given that the pandemic may persist for several years, adjustments of medical services according to the varying degrees of local breakouts are imperative to provide appropriate care for AP patients and diminish the risk of viral transmission.Registration:ClincialTrials.gov number ChiCTR2100043350.

Objective. To investigate the anesthesia effect of remifentanil combined with propofol for laparoscopic cholecystectomy and its impact on postoperative cognitive recovery. Methods. A total of 120 patients who underwent laparoscopic cholecystectomy in our hospital from February 2019 to June 2021 were recruited and assigned into either control group or experimental group at a ratio of 1 : 1 via the random number table method. The patients in the control group were anesthetized with fentanyl combined with propofol, and the patients in the experimental group were anesthetized with remifentanil combined with propofol. The clinical basic indicators (extubation time, recovery time, breathing recovery time, and orientation recovery time), and observer’s assessment of awareness/sedation (OAA/S) scores and complications were compared between the two groups. Results. There was no significant difference in extubation time between the two groups ( P > 0.05 ). The postoperative wake-up time, respiratory recovery time, and orientation recovery time of the experimental group were significantly better than those of the control group ( P < 0.05 ). The OAA/S scores of the patients in the experimental group were significantly higher than those in the control group immediately after surgery, 1 h after surgery, and 3 h after surgery ( P < 0.05 ). There was no significant difference in the OAA/S scores between the two groups on the 1st day after operation ( P > 0.05 ). The incidence of complications in the experimental group was significantly lower than that in the control group ( P < 0.05 ). Conclusion. Remifentanil + propofol for laparoscopic cholecystectomy patients has a significant anesthesia effect. This strategy effectively shortens the extubation, awakening, respiratory recovery, orientation recovery time of patients, and OAA/S score, suggest a minor impact on the postoperative cognitive function and state of consciousness. It has a high safety profile and thus is worthy of clinical application.

Supplemental material, sj-docx-1-pie-10.1177_09544089221136685 for Unsteady flow characteristics of an AFP based on energy loss and vortex identification under rotating stall condition by Xiao Qi Jia, Hao Lv and Zu Chao Zhu in Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering

Supplemental material, sj-docx-6-tag-10.1177_17562848221145552 for Impact of COVID-19 pandemic on acute pancreatitis presentations, management, and in-hospital outcomes: a single-center, retrospective observational study from the northeast of China by Zu-Chao Du, Jian Zhang, Xin-Jian Li, Zhan-Tian Zhang, Kai-Song Bai, Zi-Min Wang, Yan Xu, Xue-Wei Bai and Bei Sun in Therapeutic Advances in Gastroenterology

Supplemental material, sj-docx-1-pie-10.1177_09544089221136685 for Unsteady flow characteristics of an AFP based on energy loss and vortex identification under rotating stall condition by Xiao Qi Jia, Hao Lv and Zu Chao Zhu in Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering

Supplemental material, sj-docx-5-tag-10.1177_17562848221145552 for Impact of COVID-19 pandemic on acute pancreatitis presentations, management, and in-hospital outcomes: a single-center, retrospective observational study from the northeast of China by Zu-Chao Du, Jian Zhang, Xin-Jian Li, Zhan-Tian Zhang, Kai-Song Bai, Zi-Min Wang, Yan Xu, Xue-Wei Bai and Bei Sun in Therapeutic Advances in Gastroenterology

Supplemental material, sj-docx-5-tag-10.1177_17562848221145552 for Impact of COVID-19 pandemic on acute pancreatitis presentations, management, and in-hospital outcomes: a single-center, retrospective observational study from the northeast of China by Zu-Chao Du, Jian Zhang, Xin-Jian Li, Zhan-Tian Zhang, Kai-Song Bai, Zi-Min Wang, Yan Xu, Xue-Wei Bai and Bei Sun in Therapeutic Advances in Gastroenterology

Supplemental material, sj-docx-6-tag-10.1177_17562848221145552 for Impact of COVID-19 pandemic on acute pancreatitis presentations, management, and in-hospital outcomes: a single-center, retrospective observational study from the northeast of China by Zu-Chao Du, Jian Zhang, Xin-Jian Li, Zhan-Tian Zhang, Kai-Song Bai, Zi-Min Wang, Yan Xu, Xue-Wei Bai and Bei Sun in Therapeutic Advances in Gastroenterology

Rotating stall, as a typical unsteady flow phenomenon in the axial flow pump (AFP), might easily result in a sharp decline in the performance of the AFP, thereby affecting the safe and stable operation of the pump. To better understand the loss mechanism of flow in the AFP, this paper numerically computes the unsteady flow of an AFP with guide vanes under a variety of working conditions. Unstable flow characteristics such as flow separation, typical vortex structure and flow loss of the pump under varied working conditions are analyzed using energy loss and vortex identification methods. The analysis of boundary vorticity flow (BVF) of the pump flow field shows that unstable flow can be observed in the BVF positive peak area on the blade surface, affecting the work of the impeller. Meanwhile, there is also unsteady flow from the trailing edge of the blade to the pressure surface of the adjacent blade near the impeller hub. It is gradually enlarged to block the impeller channel as the stall aggravates, causing the formation of a ‘saddle zone’ in the AFP. The guide vane and the impeller are core areas of energy loss within the AFP. On this basis, large numbers of vortex inside the impeller and the impact of unstable flow on the blades are the main contributors to the energy loss of the impeller.

The HT-6M tokamak at the Thailand Institute of Nuclear Technology has been restarted. In order to ensure the smooth breakdown of plasma and obtain plasma discharge parameters, optimization of the poloidal field coils and upgrade of the magnetic diagnostics are described in this article. A perfect null field (stray field in the main chamber < 10 G) is obtained using an ohmic heating field. To obtain important information about the plasma, an external magnetic diagnostics system is designed and calibrated, including a Rogowski coil (measuring plasma current), a magnetic probe (measuring external field), diamagnetic loops (measuring β p) and so on. In order to realize high-frequency signal measurement and transmission, a series of frequency responses with the magnetic probe and transmission line are tested. Later, to verify the null field, a fitting code is developed to reconstruct the stray field in the vacuum chamber based on magnetic probe measurements and flux loops. The results show that the error is within 1.5%. This indicates the accuracy of the magnetic measurement system and ensures the preparation for the breakdown of plasma.

Supplemental material, sj-docx-1-pie-10.1177_09544089211063056 for Comparative analysis of transient valve-induced flow characteristics between opening and closing processes by Qi Liu, Shuai Tian, Yong-xiang Wang, Zhe Lin and Zu-chao Zhu in Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering

Supplemental material, sj-docx-1-pie-10.1177_09544089211063056 for Comparative analysis of transient valve-induced flow characteristics between opening and closing processes by Qi Liu, Shuai Tian, Yong-xiang Wang, Zhe Lin and Zu-chao Zhu in Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering

The aim of this study was to explore the effects of 2-hexyl-4-pentylenic acid (HPTA) in combination with radiotherapy (RT) on distant unirradiated breast tumors.Using a rat model of chemical carcinogen (7,12-dimethylbenz[a]anthracene,DMBA)-induced breast cancer, tumor volume was monitored and treatment response was evaluated by performing HE staining, immunohistochemistry, immunofluorescence, qRT-PCR, and western blot analyses.The results demonstrated that HPTA in combination with RT significantly delayed the growth of distant, unirradiated breast tumors. The mechanism of action included tumor-associated macrophage (TAM) infiltration into distant tumor tissues, M1 polarization, and inhibition of tumor angiogenesis by IFN-γ.The results suggest that the combination of HPTA with RT has an abscopal effect on distant tumorsThe graphical abstract was available in the web of www.besjournal.com.

The vibration was severe for a runner chamber of a large hydraulic bulb tubular turbine, which caused some cracks. The PRO/E software was adopted to establish a 3D model of the runner chamber. Based on ANSYS Workbench V14.5, a modal analysis was done. Its natural frequencies and modal shapes were obtained. The influence on modal characteristics with the runner chamber’s structure was discussed. The study shows that the reinforce stiffener’s thickness, the circumferential endlessband and their thicknesses have few effect on the modal characteristics of the runner chamber, the latticed reinforce stiffener has more effect on the modal characteristics. These results will provide the basis for product optimum design, so that its natural frequencies stagger these frequencies of field vibration, the resonance and the crack do not occur in the runner chamber.

The Buck circuit has been widely used in DC drive, charging and storage circuit, switching power supply and other power electronic devices. There exists very strong duality in the Buck circuit with input LC filter, especially in the structure of circuit, the equivalent circuits and the waveforms of input and output parts. On the basis of a theoretical model established in our work, an experiment is conducted to validate the equivalent circuits of both input and output parts, as well as the waveforms of associated capacitors and inductors. By choosing appropriate component parameters, the experimental results confirm the predictions of the theoretical model proposed.

The vibration is severe for a hydraulic turbine runner chamber of a large bulb hydraulic generator set. A measurement and analysis system is composed of an acceleration transducer, a charge amplifier, and a dynamic data collecting & analyzing system. It is used to test the frequency spectrum, which provide a basis for the optimization design based on the modal analysis, so that its natural frequencies can stagger these frequencies of vibration sources, the resonance does not occur and the vibration is reduced.

The geometrical model of the filament during the fused deposition modeling (FDM) process was firstly proposed based on three different models, tractrix, parabola, and catenary. Comparing with the actual measured filament curves on the Stratasys 1600 FDM machine, it is indicated that the tractrix model had the best agreement with the actual measured curves. With the analytical simulation, the nozzle trajectories in the straight-line deposition road, circle road, and arbitrary continuous curve road were deduced, according to the traxtric based geometrical model of the filament.

According to records from 2002, there will be a continuous increase in the number of classes, full-time teachers and teaching staff in urban primary and junior secondary schools during the period 2005–2020. At the same time, the demand for classes and teachers of non-compulsory education will decrease yearly. It is estimated that the budgetary funds for urban primary, junior secondary, senior secondary education and even higher education will increase by 8%, 8.7%, 15.2% and 9%, respectively each year.

2-(2′-Oxo-3′-oximidocyclododecyl) cyclododecanone (1) and 2-(1′-hydroxylcyclododecyl) cyclododecanone (2) were synthesized and characterized. The conformation analysis was carried out based on the NMR, molecular mechanics calculation and X-ray diffraction. The conformation of two cyclododecyl moieties of both 1 and 2 was found to be the [3333]-2-one or [3333] square conformation both in the crystal state and the solution. The dihedral angle between carbonyl and the oxime double bond of the ring B is 180° in the crystal of 1. The protons or hydroxyl group of carbon atoms to link the two cyclododecyl moieties of 1 and 2 constitute dihedral angles of 174° in the crystal, and 175° in the solution, and the CC σ bond between two cyclododecyl moieties can not freely rotate in the solid state and the solution. In addition, compound 2 was the first example of α-corner-anti-monosubstituted cyclododecanone.

The present study was designed to determine the taxonomic diversity and metabolic activity of the actinomycetes community, including 13 traditional medicinal plants collected in Sichuan province, China, using multiple approaches such as morphological and molecular identification methods, bioactivity assays, and PCR screening for genes involved in antibiotics biosynthesis. 119 endophytic actinomycetes were recovered; 80 representative strains were chosen for 16S rRNA gene partial sequence analyses, with 66 of them being affiliated to genus Streptomyces and the remaining 14 strains being rare actinomycetes. Antimicrobial tests showed that 12 (15%) of the 80 endophytic actinomycetes displayed inhibitory effects against at least one indicator pathogens, which were all assigned to the genus Streptomyces. In addition, 87.5% and 58.8% of the isolates showed anticancer and anti-diabetic activities, respectively. Meanwhile, the anticancer activities of the isolates negatively correlated with their anti-diabetic activities. Based on the results of PCR screening, five genes, PKS-I, PKS-II, NRPS, ANSA, and oxyB, were detected in 55.0%, 58.8%, 90.0%, 18.8% and 8.8% of the 80 actinomycetes, respectively. In conclusion, the PCR screening method employed in the present study was conducive for screening and selection of potential actinomycetes and predicting potential secondary metabolites, which could overcome the limitations of traditional activity screening models.

In this paper, the collision detection and response that based on the OBB (oriented bounding boxes) tree structure was realized in virtual surgery simulation system for nasopharyngeal carcinoma. The point of contact location and the vector of contact surface can be acquired. The force effect in virtual surgery simulation was improved. A twice detection method was proposed to improve the phenomenon of the force puncture, and a synchronize mechanism was adopt to improve the stability of the force output. Simulation results show that the improved algorithm has been enhanced in the force puncture and stability of the force, and the force effect is more authentic.

New control technology is being applied in time in different industries including non-shuttle weaving machine as it is developed maturely. In this study, a new control system, multi-CPUs based, for air-jet weaving machine is presented. Advanced architecture is adopted in the control system which incorporates the advantages of the processors to meet the function requirements, including a central control module, human-machine interface module, and electrical let-off/take-up module etc. It promises the weaving machine running in high efficiency and managing in simplicity. Also it provides a valuable guide for air-jet weaving machine researchers by establishing a better understanding of a control system in air-jet weaving machine.

To compare the mechanical properties of point contact-dynamic compression plate (PC-DCP) and its effects on cortical bone perfusion with that of dynamic compression plates (DCP) in goat tibiae.Twenty pairs of matched fresh goat tibiae were used. A transverse fracture model was established. The fractures with a 3mm interspace between the fracture ends were subject to fixations with the DCPs and the PC-DCPs respectively, then the four-points bending tests and the torsion tests were conducted to compare the mechanical properties of the PC-DCP with that of DCP. Another 13 sexually mature goats underwent fixations with the DCPs and the PC-DCPs, respectively, at the mid-shafts of the intact bilateral tibiae. Ischemic zones were observed at four time points (1 day, 2, 6, and 12 weeks after operation) using disulphine blue staining technique.There were no significant differences in mechanical properties, such as bend- and torsion-resistance, between the DCPs and the PC-DCPs. One day, 2, and 6 weeks after operation, on the side of DCP fixation, outer cortical bone ischemia under the plate persisted, and this condition did not reverse until 12 weeks after operation. However, on the side of PC-DCP fixation, cortical bone ischemia occurred only in the periphery of the screw holes and at the contact sites of the PC NUTs 1 day after operation, and it disappeared at 2 weeks after operation.The PC-DCP has similar biomechanical properties of the DCP, but is less detrimental to local bone blood circulation than the conventional plates.

To establish a HPLC method for determining orientin and vitexin in Trollius chinesis preparation.The separation was carried out on Hypersil ODS column with a mixture of acetonitrile-1% acetic acid solution (15:85) as the mobile phase, at a flow rate of 1.0 mL x min(-1). The detection wavelength was set 340 nm.Orientin showed a good linear relationship in the range of 8.42-84.2 microg x mL(-1) (r = 0.9999) and the average recovery is 98.3%, RSD is 0.8%. Vitexin showed a good linear relationship in the range of 8.07-80.7 microg x mL(-1) (r = 0.9999) and the average recovery is 102.4%. RSD is 1.7%.The method is sensitive, specific, and accurate with a good repeatability and can be used for the quality control of Trollius chinesis preparation.