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In order to study the influence of the circumferential position of the balance hole on the cavitation performance of the semiopen impeller centrifugal pump, a low specific speed semiopen impeller centrifugal pump is taken as the object, and 4 kinds of circumferential positions of balance holes are designed. The SST k-ω turbulence model and the Rayleigh–Plesset cavitation bubble dynamics equation are used to calculate the full flow field of the centrifugal pump. Research shows that, under cavitation conditions, as the circumferential position of the balance hole is farther away from the blade working surface, the cavitation performance of the pump is reduced, and the larger θ (the angle of the balance hole and the leading edge of the blade in the direction of rotation) is, the easier the jet cavitation occurs near the balance hole. On the other hand, with the development of cavitation, the axial force of the impeller has also changed greatly. In contrast, the farther the balance hole is arranged in the circumferential direction (i.e., the greater θ), the more limited is the ability of the balance hole to balance the axial force.

Amphioxus species are considered living fossils and are important in the evolutionary study of chordates and vertebrates. To explore viral homologous sequences, a high-quality annotated genome of the Beihai amphioxus (Branchiostoma belcheri beihai) was examined using virus sequence queries. In this study, 347 homologous fragments (HFs) of viruses were identified in the genome of B. belcheri beihai, of which most were observed on 21 genome assembly scaffolds. HFs were preferentially located within protein-coding genes, particularly in their CDS regions and promoters. A range of amphioxus genes with a high frequency of HFs is proposed, including histone-related genes that are homologous to the Histone or Histone H2B domains of viruses. Together, this comprehensive analysis of viral HFs provides insights into the neglected role of viral integration in the evolution of amphioxus.

Traditional Chinese Medicine prescription Suanzaoren decoction (SZRD) is composed of Ziziphi Spinosae Semen, Chuanxiong Rhizoma, Anemarrhenae rhizoma, Poria and Licorice. It was used to treat central nervous system diseases such as insomnia and anxiety for thousands of years. This paper aims to systematically understand varieties and quantities of compounds and clarify chemical components of SZRD, subsequently to further provide the reference for phytochemistry and pharmacology researches of SZRD. Our results showed that SZRD contained 145 components, including flavonoids, triterpenoids, steroids, coumarins, phthalides, and volatile oils, etc., while five-single herbs contain 1104 components. Only in terms of compound number, there were 80 common components in SZRD and its five herbs, which accounted for 6.8% of total compounds in all 5 herbs and 55.2% of compounds in SZRD. The components of SZRD were not simply the sum of one in every single herb. It is necessary to perform parallel studies among SZRD and its herbs. This review discussed the problems that existed in the chemical research of SZRD and pointed out the direction for its further research.

In order to study the influence of the circumferential placement position of the guide vane on the flow field and stress-strain of a nuclear reactor coolant pump, the CAP1400 nuclear reactor coolant pump is taken as the research object. Based on numerical calculation and test results, the influence of circumferential placement position of the guide vane on the performance of the nuclear reactor coolant pump and stress-strain of guide vanes are analyzed by the unidirectional fluid-solid coupling method. The results show that the physical model and calculation method used in the study can accurately reflect the influence of the circumferential placement position of the guide vane on the nuclear reactor coolant pump. In the design condition, guide vane position has a great influence on the nuclear reactor coolant pump efficiency value, suction surface of the guide vane blade, and the maximum equivalent stress on the hub. However, it has a weak effect on the head value, pressure surface of the guide vane blade, and the maximum equivalent stress on the shroud. When the center line of the outlet diffuser channel of the case is located at the center of the outlet of flow channel of the guide vane, it is an optimal guide vane circumferential placement position, which can reduce the hydraulic loss of half of the case. Finally, it is found that the high stress concentration area is at the intersection of the exit edge of the vane blade and the front and rear cover, and the exit edge of the guide vane blade and its intersection with the front cover are areas where the strength damage is most likely to occur. This study provides a reference for nuclear reactor coolant pump installation, shock absorption design, and structural optimization.

Anxiety is a common, universal disease caused by psychological and environmental factors. There are medications available to treat anxiety disorders, but these are accompanied by problems such as addiction and withdrawal difficulties. Suanzaoren Prescription (SZRP) is often used to treat anxiety disorders in traditional Chinese medicine clinical practice. However, its therapeutic mechanism remains unclear. This work aims to identify potential core therapeutic targets and predict major bioactive compounds by means of network pharmacology, screen compounds that may bind to anxiety targets by molecular docking methods, and validate and evaluate possible therapeutic mechanisms of compounds for anxiety in vitro cell experiments. Datebase TCMSP, BATMAN-TCM, ETCM, TCMGeneDIT and TCMID was used to obtain SZRP compounds, while TCMSP, BATMAN-TCM and ETCM were used to obtain target of compounds. The targets of anxiety disorders were obtained through database TTD, OMIM, PharmgKB, CTD, DrugBank and Metacore. The network diagram is drawn by Cytoscape 3.7.2 software and STRING. Biological process and KEGG pathway analysis were conducted by MetaCore and NIMNT. AutoDock Vina software was used to conduct molecular docking. The calcium Flux assay was employed to detect the activation of compounds on CNR1 in cell line CHO-K1/CNR1/Gα15. The 545 compounds in SZRP were collected. We found there were 1050 potential targets of these compounds in SZRP which involved in brain disease, mood disorder, endocrine system disease, bipolar disorder, etc. There were 117 potential targets of SZRP against anxiety (such as DRD2, BDNF, COMT, SLC6A4, HTR1A, etc.), which played the roles in regulation of membrane potential and synaptic transmission, nicotine addiction, retinol metabolism, GABAergic and serotonergic synapse, etc. The results of molecular docking indicated there were the biggest affinity between Jujuboside B and DRD2, BDNF, COMT, SLC6A4, Anemarsaponin B_qt and HTR1A, n-methylasimilobine and MAPK3. Based on cell CHO-K1/CNR1/Gα15 and calcium flux technique, we found Chrysophanol, Kaempferol and Emodin have activation effects on CNR1 with EC50 138.3µM, 52.28µM and 56.86µM respectively. These results indicated that the effects of SZRP against anxiety were correlated with synaptic transmission, substance addiction and retinol metabolism, especially targeted on CNR1. It suggested that the therapeutic mechanism of SZRP treating anxiety might be due to the weak action of multiple compounds on multiple pathways and biological processes.

In order to study the effects of inlet sweepback angle on the cavitation performance of inducers based on the Reynolds N-S equation, RNG k-ε turbulent model, and Schnerr and Sauer cavitation model, a three-dimensional numerical calculation is employed to study the flow characteristics of a certain LNG pump. Laws of the variation of cavitation performance, head, and efficiency with the change of sweepback were studied. Numerical analysis of the eight inducer projects with a sweepback angle from 120° to 290° was carried out. The results show that the cavitation bubbles first appear at the suction surface near the inlet side. With the decrease of net positive suction head (NPSHa), the bubbles spread to the outlet side of the inducer and the pressure surface. Finally, they fill the entire channel. When the inducer sweepback angle increases from 120° to 270°, the NPSHr of the pump reduces gradually, that is to say that the anti-cavitation performance of the pump has been improved. However, the NPSHr of the pump increases gradually when the inducer sweepback angle increases from 270° to 290°. In other words, there is an optimal sweepback from 120° to 290°, and efficiency and head of pump tend to be stable near the optimal sweepback.

Based on the RNG k–ɛ turbulence model, the multi-coordinate system is used to simulate the three-dimensional unsteady constant value of the nuclear main pump model under different axial and circumferential positions of the guide vane and the annular casing. By analyzing the external characteristics, pressure field and velocity field of different schemes and comparing the pressure pulsation at the impeller outlet, the flow of guide vane and the annular casing is studied through the axial and circumferential position changes in the vane and the annular casing. The results show that the axial distance between the center line of the guide vane and the center line of the outlet extension will increase the uneven distribution of pressure in the impeller outlet and the annular casing and the circumferential position of the guide vane will increase as well. When the center lines of the two are coincident, the pressure distribution in the impeller outlet and the casing is relatively uniform. The change in the axial and circumferential positions of the guide vane of the nuclear main pump has little effect on the vector distribution of the impeller outlet flow, and the influence of liquid flow in the interior of casing is large. The impeller outlet pressure pulsation increases as the axial distance between the guide vane outlet center line and the annular casing outlet center line increases. When the two center lines coincide, the impeller outlet pressure pulsation peak is the lowest.

Mounting evidence points to alterations in the gut microbiota-neuroendocrine immunomodulation (NIM) network that might drive Alzheimer's Disease (AD) pathology. In previous studies, we found that Liuwei Dihuang decoction (LW) had beneficial effects on the cognitive impairments and gastrointestinal microbiota dysbiosis in an AD mouse model. In particular, CA-30 is an oligosaccharide fraction derived from LW. We sought to determine the effects of CA-30 on the composition and function of the intestinal microbiome in the senescence-accelerated mouse prone 8 (SAMP8) mouse strain, an AD mouse model. Treatment with CA-30 delayed aging processes, ameliorated cognition in SAMP8 mice. Moreover, CA-30 ameliorated abnormal NIM network in SAMP8 mice. In addition, we found that CA-30 mainly altered the abundance of four genera and 10 newborn genera. Advantageous changes in carbohydrate-active enzymes of SAMP8 mice following CA-30 treatment, especially GH85, were also noted. We further found that seven genera were significantly correlated with the NIM network and cognitive performance. CA-30 influenced the relative abundance of these intestinal microbiomes in SAMP8 mice and restored them to SAMR1 mouse levels. CA-30 ameliorated the intestinal microbiome, rebalanced the NIM network, improved the AD-like cognitive impairments in SAMP8 mice, and can thus be a potential therapeutic agent for AD.

Glycosylation is one of the most common eukaryotic post-translational modifications, and aberrant glycosylation has been linked to many diseases. However, glycosylation and glycome analysis is a significantly challenging task. Although several lines of evidence have indicated that protein glycosylation is defective in Alzheimer’s disease (AD), only a few studies have focused on AD glycomics. The etiology of AD is unclear and there are no effective disease-modifying treatments for AD. In this study, we found that the object recognition memory, passive avoidance, and spatial learning and memory of senescence-accelerated mouse prone 8 (SAMP8) strain, an AD animal model, were deficient, and LW-AFC, which was prepared from the traditional Chinese medicine prescription Liuwei Dihuang decoction, showed beneficial effects on the deterioration of cognitive capability in SAMP8 mice. Forty-three and 56 N-glycan were identified in the cerebral cortex and serum of SAMP8 mice, respectively. The N-glycan profile in SAMP8 mice was significantly different from that of senescence accelerated mouse resistant 1 (SAMR1) strains, the control of SAMP8 mice. Treatment with LW-AFC modulated the abundance of 21 and 6 N-glycan in the cerebral cortex and serum of SAMP8 mice, respectively. The abundance of (Hex)3(HexNAc)5(Fuc)1(Neu5Ac)1 and (Hex)2(HexNAc)4 decreased in the cerebral cortex and serum of SAMP8 mice compared with SAMR1 mice, decreases that were significantly correlated with learning and memory measures. The administration of LW-AFC could reverse or increase these levels in SAMP8 mice. These results indicated that the effects of LW-AFC on cognitive impairments in SAMP8 mice might be through modulation of N-glycan patterns, and LW-AFC may be a potential anti-AD agent.

Compared with the general centrifugal pump, the screw centrifugal pump has a spiral radial impeller and opening flow passage. The impeller inlet is a spiral blade and outlet of blade looks like to mixing-flow pump blade. Its special structure made the screw pump not only having spiral propelling effect but also having centrifugal effect, therefore the screw centrifugal pump has both the merits of screw pump and centrifugal pump. According to the structure characteristics of screw centrifugal pump, character of flow-field inside the pump and projection drawing on foundation with one-dimension, the regularity for change of pitch in the variable-pitch parametric equation group is given in this paper. And the variable-pitch parameter equation group of the screw centrifugal pump is perfected. Using the parametric equation, to segment streamline dots on axial plane for designing screw centrifugal pump blade is facilitated, which has important meaning to the CAD, numerical simulation of three-dimension flow-field and improve performances of screw centrifugal pump

Based on the Reynolds-averaged Navier–Stokes equations of relative coordinates and the RNG k-ε turbulence model, using our SIMPLE algorithm, we performed numerical simulations for an AP1000 nuclear main pump model with water as the medium. By changing the size of the tongue blend in the annular casing, seven different schemes were designed. Three-dimensional numerical simulations were conducted for the flow within the pump under various settings, and the flow characteristics of the annular casing using different tongue blends were obtained. The results show that for different operating conditions, there is a specific tongue blend that optimizes pump performance. Based on the calculation results, a larger tongue blend leads to a larger flow rate. Off-design conditions caused flow instability, which in turn caused the tongue blend to have a certain impact on the performance of the impeller. However, the performance of the pump was not primarily affected by changes in the impeller performance, but was instead affected by the performance of the annular casing, which was itself affected by tongue blend. When changing the tongue blend, the change in static pressure and total pressure of the annular casing was larger under the condition of 0.6 Qd and was smaller under the conditions of 1.0 Qd and 1.4 Qd. The turbulent kinetic energy in the annular casing changed mainly in the tongue impact zone and outlet diffuser under the condition of 1.0 Qd; furthermore, the turbulent kinetic energy in the whole of the annular casing demonstrated significant changes under the conditions of 0.6 Qd and 1.4 Qd.