Revisiting the Evidence for an Intermediate-mass Black Hole in the Center of NGC 6624 with Simulations

The acceleration of LMXB 4U 1820-30 derived from its orbital-period derivative P_(b)was supposed to be the evidence for an Intermediate-mass black hole(IMBH)in the Galactic globular cluster(GC)NGC 6624.However,we find that the anomalous P_(b)is mainly due to the gravitational wave emission,rather than the acceleration in cluster potential.Using the standard structure models of GCs,we simulate acceleration distributions for pulsars in the central region of the cluster.By fitting the acceleration of J1823-3021 A with the simulated distribution profiles(maximum values),it is suggested that an IMBH with mass M■950_(-350)^(+550)M_(⊙) may reside in the cluster center.We further show that the second period derivative P of J1823-3021 A is probably due to the gravitational perturbation of a nearby star.

Undergraduate Experimental Teaching Platform for Intelligent Limb Rehabilitation Training Based on "Medical-Engineering Interdisciplinary Crossing"

In view of the key role of undergraduate experimental teaching reform in cultivating high-quality talents with both innovative spirit and practical ability,this paper deeply discusses multi-dimensional reform strategies.Specifically,the teaching mode of"double teachers for every student"is innovatively introduced,and scientific research projects are deeply integrated into undergraduate experimental teaching,aiming at realizing the modern development of teaching content and the diversified expansion of teaching methods.By designing and applying the undergraduate experimental teaching platform for intelligent limb rehabilitation training based on the concept of"medical-engineering interdisciplinary crossing",it not only builds a bridge for students to contact cutting-edge scientific research and strengthen practical skills,but also provides valuable ideas and practical models for the innovation of undergraduate experimental teaching.In the future,with the continuous optimization and upgrading of platform functions,it is expected to provide students with a richer and richer learning experience and comprehensively promote students'overall quality.

The Application of Permanent Magnet Synchronous Motor with Small Electrical Time Constant in Fiber Positioner

With the development of cutting-edge multi-object spectrographs,fiber positioners located in the focal plane are being scaled down in size,and miniature hollow-cup Permanent Magnet motors are now being considered as a suitable replacement for Faulhaber Precistep stepper motors.However,the small electrical time constant of such coreless motors poses a challenge,as the problem of severe commutation torque ripple in a fiber positioner running a position loop has been tricky.To overcome this challenge,it is advised to increase the Pulse Width Modulation(PWM)frequency as much as possible to mitigate the effects of the current fluctuation.This must be done while ensuring adequate resolution of the PWM generator.By employing a voltage open-loop field-oriented control based on a modulation frequency of 1 MHz,the drive current only costs 25 m A under a 3.3 V power supply.The sine degree of phase current is immaculate,and the repeat positioning accuracy can reach 2μm.Moreover,it is possible to further shrink the bill of devices and the layout area of the Printed Circuit Board,especially in sizesensitive applications.This device has been developed under the new generation of The Large Sky Area MultiObject Fiber Spectroscopic Telescope.

Exploration and Practice of the"One-Student-Two-Tutors"Community through Integrating"1+3 Teaching Resources"into Undergraduate Experimental Teaching

This study closely follows the spirit of the first class undergraduate education action plan(2021-2025)of University of Shanghai for Science and Technology,combines with the national first-class undergraduate professional training plan of mechanical design and manufacturing and automation,and carries out the exploration and practice of"1+3 teaching resources"integrating into the"One-Student-Two-Tutors"community of undergraduate experimental teaching.On the basis of creating a good learning environment and creating an excellent learning platform,this paper studies the undergraduate experimental teaching of the trinity of"theoretical courses+experimental courses+innovation and entrepreneurship activities,discipline competitions,and scientific research project activities".This study has a certain reference value for colleges and universities to cultivate outstanding engineering talents with happy learning attitude,scientific research interest,practical ability and innovative ability.

Application and Practice of Knowledge Graph in Experimental Teaching in Colleges and Universities

With the reform of experimental teaching in colleges and universities,the teaching mode of"experimental students as the main body,experimental teachers as the guide"needs to constantly explore new experimental teaching methods.In this paper,knowledge graph is integrated into the experiment of mechanical principle to guide undergraduates to use knowledge graph to analyze and summarize independently in experimental teaching activities,aiming at cultivating undergraduates interest in learning and innovative thinking,so as to improve the quality of experimental teaching.This study has a certain reference significance for experimental teaching in colleges and universities.

Mo_(2)P Monolayer as a Superior Electrocatalyst for Urea Synthesis from Nitrogen and Carbon Dioxide Fixation:A Computational Study

Urea synthesis through the simultaneous electrocatalytic reduction of N_(2)and CO_(2)molecules under ambient conditions holds great promises as a sustainable alternative to its industrial production,in which the development of stable,highly efficient,and highly selective catalysts to boost the chemisorption,activation,and coupling of inert N_(2)and CO_(2)molecules remains rather challenging.Herein,by means of density functional theory computations,we proposed a new class of two-dimensional nanomaterials,namely,transition-metal phosphide monolayers(TM_(2)P,TM=Ti,Fe,Zr,Mo,and W),as the potential electrocatalysts for urea production.Our results showed that these TM_(2)P materials exhibit outstanding stability and excellent metallic properties.Interestingly,the Mo_(2)P monolayer was screened out as the best catalyst for urea synthesis due to its small kinetic energy barrier(0.35 eV)for C-N coupling,low limiting potential(-0.39 V),and significant suppressing effects on the competing side reactions.The outstanding catalytic activity of the Mo_(2)P monolayer can be ascribed to its optimal adsorption strength with the key^(*)NCON species due to its moderate positive charges on the Mo active sites.Our findings not only propose a novel catalyst with high-efficiency and high-selectivity for urea production but also further widen the potential applications of metal phosphides in electrocatalysis.

YTE-17 inhibits colonic carcinogenesis by resetting antitumor immune response via Wnt5a/JNK mediated metabolic signaling

The density and composition of lymphocytes infiltrating colon tumors serve as predictive factors for the clinical outcome of colon cancer.Our previous studies highlighted the potent anti-cancer properties of the principal compounds found in Garcinia yunnanensis(YTE-17),attributing these effects to the regu-lation of multiple signaling pathways.However,knowledge regarding the mechanism and effect of YTE-17 in the prevention of colorectal cancer is limited.In this study,we conducted isobaric tags for relative and absolute quantification(iTRAQ)analysis on intestinal epithelial cells(IECs)exposed YTE-17,both in vitro and in vivo,revealing a significant inhibition of the Wnt family member 5a(Wnt5a)/c-Jun N-terminal kinase(JNK)signaling pathway.Subsequently,we elucidated the influence and mechanism of YTE-17 on the tumor microenvironment(TME),specifically focusing on macrophage-mediated T helper 17(Th17)cell induction in a colitis-associated cancer(CAC)model with Wnt5a deletion.Additionally,we performed the single-cell RNA sequencing(scRNA-seq)on the colonic tissue from the Wnt5a-deleted CAC model to characterize the composition,lineage,and functional status of immune mesenchymal cells during different stages of colorectal cancer(CRC)progression.Remarkably,our findings demon-strate a significant reduction in M2 macrophage polarization and Th17 cell phenotype upon treatment with YTE-17,leading to the restoration of regulatory T(Treg)/Th17 cell balance in azoxymethane(AOM)/dextran sodium sulfate(DSS)model.Furthermore,we also confirmed that YTE-17 effectively inhibited the glycolysis of Th17 cells in both direct and indirect co-culture systems with M2 macrophages.Notably,our study shed light on potential mechanisms linking the non-canonical Wnt5a/JNK signaling pathway and well-established canonical b-catenin oncogenic pathway in vivo.Specifically,we proposed that Wnt5a/JNK signaling activity in IECs promotes the development of cancer stem cells with b-catenin activity within the TME,involving macrophages and T cells.In summary,our study undergoes the po-tential of YTE-17 as a preventive strategy against CRC development by addressing the imbalance with the immune microenvironment,thereby mitigating the risk of malignancies.

Guidelines for application of high-content screening in traditional Chinese medicine:concept,equipment,and troubleshooting

High-content screening(HCS)technology combines automated high-speed imaging hardware and single-cell quantitative analysis.It can greatly accelerate data acquisition in cellular fluorescence imaging and is a powerful research technique in traditional Chinese medicine(TCM).An increasing number of laboratories and platforms,including TCM laboratories,have begun utilizing HCS systems.However,this technology is still in its infancy in TCM research and there is a lack of sufficient experience with the associated concepts,instrument configurations,and analysis methods.To improve the understanding of HCS among researchers in the field of TCM,this paper summarizes the concept of HCS,software and hardware configuration,the overall research process,as well as common problems and related solutions of HCS in TCM research based on our team’s previous research experience,providing several research examples and an outlook on future perspectives,aiming to provide a technical guide for HCS in TCM research.

Influence of Rare Earth Elements on Microstructure and Mechanical Properties of Cast High-Speed Steel Rolls

The influence of rare earth （RE） elements on the solidification process and eutectic transformation and mechanical properties of the high-V type cast, high-speed steel roll was studied. Test materials with different RE additions were prepared on a horizontal centrifugal casting machine. The solidification process, eutectic structure transformation, carbide morphology, and the elements present, were all investigated by means of differential scanning calorimetry （DSC） and scanning electron microscopy energy dispersive spectrometry （SEM-EDS）. The energy produced by crack initiation and crack extension was analyzed using a digital impact test machine. It was found that rare earth elements increased the tensile strength of the steel by inducing crystallization of earlier eutectic γ-Fe during the solidification process, which in turn increased the solidification temperature and thinned the dendritic grains. Rare earth elements with large atomic radius changed the lattice parameters of the MC carbide by forming rare earth carbides. This had the effect of dispersing longpole M C carbides to provide carbide grains, thereby, reducing the formation of the gross carbide and making more V available, to increase the secondary hardening process and improve the hardness level. The presence of rare earth elements in the steel raised the impact toughness by changing the mechanism of MC carbide formation, thereby increasing the crack initiation energy.

Dachaihu decoction ameliorates pancreatic fibrosis by inhibiting macrophage infiltration in chronic pancreatitis

AIM To explore the role of macrophages in chronic pancreatitis(CP) and the effect of Dachaihu decoction(DCHD) on pancreatic fibrosis in mice.METHODS Kun Ming mice were randomly divided into a control group, CP group, and DCHD group. In the CP and DCHD groups, mice were intraperitoneally injected with 20% L-arginine(3 g/kg twice 1 d/wk for 6 wk). Mice in the DCHD group were administered DCHD intragastrically at a dose of 14 g/kg/d 1 wk after CP induction. At 2 wk, 4 wk and 6 wk post-modeling, the morphology of the pancreas was observed using hematoxylin and eosin, and Masson staining. Interleukin-6(IL-6) serum levels were assayed using an enzyme-linked immunosorbent assay. Double immunofluorescence staining was performed to observe the co-expression of F4/80 and IL-6 in the pancreas. Inflammatory factors including monocyte chemoattractant protein-1(MCP-1), macrophage inflammatory protein-1α(MIP-1α) and IL-6 were determined using real time-polymerase chain reaction. Western blot analysis was used to detect fibronectin levels in the pancreas. RESULTS Compared with the control group, mice with 20% L-arginine-induced CP had obvious macrophage infiltration and a higher level of fibrosis. IL-6 serum concentrations were significantly increased. Double immunofluorescence staining showed that IL-6 and F4/80 were co-expressed in the pancreas. With the administration of DCHD, the infiltration of macrophages and degree of fibrosis in the pancreas were significantly attenuated; IL-6, MCP-1 and MIP-1α m RNA, and fibronectin levels were reduced. CONCLUSION The dominant role of macrophages in the development of CP was mainly related to IL-6 production. DCHD was effective in ameliorating pancreatic fibrosis by inhibiting macrophage infiltration and inflammatory factor secretion in the pancreas.

Computed morphometric analysis and expression of alpha fetoprotein in hepatocellular carcinoma and its related lesion

INTRODUCTION Hepatocellular carcinoma(HCC)is closely relatedwith hepatitis and cirrhosis.In order to investigatethe pathogenesis and early pathologic diagnosis ofHCC,HCC and related lesions were analyzedqualitively and quantitively by automatic imageanalysor and immunohistochemical assay.

Preparation of CS-CMC Bipolar Membrane and its Application in Electro-generated FeO_4^(2-)

CS-CMC bipolar membrane was prepared and the cross-section photograph of CS-CMC BM was observed by SEM. FT-IR spectrum indicated that CS-CMC BM contained -N=CRH2^＋ and -COO^- functional groups. The charge density of -N--CRH2^＋ in CS membrane was about 14.13 mmol/g and the charge density of -COO in CMC membrane was about 9.01 mmol/g. The electrochemistry properties of CS-CMC BM were also studied. CS-CMC BM not only can effectively stop FeO4^2- from diffusing into the cathode chamber, but also plays an important role in the supply of OH＂ consumed during the electro-generated FeO4^2- process.

Influence of chronic intermittent hypoxia on growth associated protein 43 expression in the hippocampus of young rats

This study aimed to explore the pathological change to hippocampal neurons and the expression of growth associated protein 43 in 21-day-old young rats following chronic intermittent hypoxia. Hematoxylin-eosin staining results showed varying degrees of degeneration and necrosis in hippocampal neurons depending on the modeling time. Immunohistochemistry revealed that growth associated protein 43 expression in young rats following chronic intermittent hypoxia decreased, but that levels were still higher than those of normal rats at each time point, especially 4 weeks after modeling. During 1 5 weeks after modeling, a slow growth in rat weight was observed. Experimental findings indicate that chronic intermittent hypoxia may induce growth dysfunction and necrosis of hippocampal neurons, as well as increase the expression of growth associated protein 43 in young rats.

A deep-learning-based prediction method of the estimated ultimate recovery(EUR)of shale gas wells

The estimated ultimate recovery(EUR)of shale gas wells is influenced by many factors,and the accurate prediction still faces certain challenges.As an artificial intelligence algorithm,deep learning yields notable advantages in nonlinear regression.Therefore,it is feasible to predict the EUR of shale gas wells based on a deep-learning algorithm.In this paper,according to geological evaluation data,hydraulic fracturing data,production data and EUR evaluation results of 282 wells in the WY shale gas field,a deep-learning-based algorithm for EUR evaluation of shale gas wells was designed and realized.First,the existing EUR evaluation methods of shale gas wells and the deep feedforward neural network algorithm was systematically analyzed.Second,the technical process of a deep-learning-based algorithm for EUR prediction of shale gas wells was designed.Finally,by means of real data obtained from the WY shale gas field,several different cases were applied to testify the validity and accuracy of the proposed approach.The results show that the EUR prediction with high accuracy.In addition,the results are affected by the variety and number of input parameters,the network structure and hyperparameters.The proposed approach can be extended to other shale fields using the similar technic process.

A Method for Crude Oil Selection and Blending Optimization Based on Improved Cuckoo Search Algorithm

Refineries often need to find similar crude oil to replace the scarce crude oil for stabilizing the feedstock property. We introduced the method for calculation of crude blended properties firstly, and then created a crude oil selection and blending optimization model based on the data of crude oil property. The model is a mixed-integer nonlinear programming(MINLP) with constraints, and the target is to maximize the similarity between the blended crude oil and the objective crude oil. Furthermore, the model takes into account the selection of crude oils and their blending ratios simultaneously, and transforms the problem of looking for similar crude oil into the crude oil selection and blending optimization problem. We applied the Improved Cuckoo Search(ICS) algorithm to solving the model. Through the simulations, ICS was compared with the genetic algorithm, the particle swarm optimization algorithm and the CPLEX solver. The results show that ICS has very good optimization efficiency. The blending solution can provide a reference for refineries to find the similar crude oil. And the method proposed can also give some references to selection and blending optimization of other materials.

Fenton Reagent Generated in Electrolysis Cell and Its Usage in Degradation and Decolorization of Dyes

The Electro-chemistry process to produce Fenton reagents has been described. The in situ oxidation of dyes, acid chrome and alizarin red(Fenton reagents) with electrogenerated hydroxyl radicals was investigated. The \{ I-V \} cyclic voltammograms were measured. The redox peaks of the dyes were not observed in the treated dye solutions instead of a couple of O_2/H_2O_2 redox peaks. The IR results indicate that acid chrome dye was decomposed into naphthylamine and phenol aminophenol sulfonic acid. The degradation and the decolorization of the dyes were comfirmed by the visible spectrum and the chemical analysis. The COD_ cr removing rate was close to 80%.

Growth-inhibiting and Apoptosis-inducing Effects of Tanshinone ⅡA on Human Gastric Carcinoma Cells

To explore the effects of Tanshinone Ⅱ A on the proliferation, apoptosis and gene expression of p53 and bcl-2 in human gastric carcinoma MKN-45 cells. Cell count and MTT assay were used to study the proliferation-inhibiting effect of Tanshinone Ⅱ A on MKN-45 cells. The effect of Tanshinone Ⅱ A on the cell cycle and apoptosis of MKN-45 cells were examined by propidium iodide （PI） staining and flow cytometry. Semi-quantitative RT-PCR was used to further verify the ex- pression of p53 and bcl-2 gene after exposure to Tanshinone Ⅱ A in MKN-45 cells. The results showed that Tanshinone Ⅱ A significantly inhibited the growth and proliferation of MKN-45 cells in a dose- and time-dependent manner （P〈0.05）. Tanshinone Ⅱ A arrested MKN-45 cells in G2/M phase which led to an obvious accumulation of G2/M phase cells while decreased number of Go/G1 phase cells. This resulted in apoptosis of MKN-45 cells and the apoptosis rate was as high as 43.91% after treatment with 2.0 lag/mL Tanshinone Ⅱ A for 96 h. It was also found that Tanshinone Ⅱ A up-regulated expression of p53 gene and down-regulated expression of bcl-2 gene. The cytostatic and antiproliferative effect of Tanshinone Ⅱ A makes it a promising anticancer agent for the treatment of gastric carcinoma.

Mechanism of action of Zhuyu Annao pill in mice with cerebral intrahemorrhage based on TLR4

Objective:To explore the protective effect and possible mechanism of action of Zhuyu Annao pill in mice with intracerebral hemorrhage(ICH).Methods:Sixty mice were divided into the control group,hemorrhage group,drug-treated group(after hemorrhage),TLR4-knockout hemorrhage group and TLR4-knockout hemorrhage + drug-treated group(after hemorrhage) with 12 in each group.Model of autologous ICH was established in all groups.After drilling and 12 h of fasting,models in the control group hemorrhage group and TLR4-knockout hemorrhage group were all drenched with 10 mL/kg distilled water by intragastric administration.Models in the drug-treated group and TLR4-knockout hemorrhage + drugtreated group were drenched with 6.25 g/kg of Zhuyu Annao pill.All groups were treated for 7 d.Longa scoring method was used to measure the neurological defect scores and determine the brain water contents of all groups;ELISA was employed to detect the inflammatory factor interleukin(IL)-6,tumor necrosis factor- α(TNF- α) and IL-1β in brain tissues;and Western blot was applied to test the expression quantities of apoptotic protein Bax and anti-apoptotic protein Bcl-2 in brain tissues.Results:At day 3 and7,compared with the hemorrhage group,the neurological defect scores of the drug-treated group,TLR4-knockout hemorrhage group and TLR4-knockout hemorrhage + drug-treated group decreased significantly(P<0.05) Compared with the hemorrhage group,the brain water contents of the drug-treated group,TLR4-knockout hemorrhage group and TLR4-knockout hemorrhage + drug-treated group reduced significantly(P<0.05) Compared with the hemorrhage group,the inflammatory factor IL-6,TNF-α and IL-1β of the drug-treated group,TLR4-knockout hemorrhage group and TLR4-knockout hemorrhage + drug-treated group decreased significantly(P<0.05).Compared with the hemorrhage group,the expression of apoptotic protein Bax of the drug-treated group,TLR4-knockout hemorrhage group and TLR4-knockout hemorrhage+ drug-treated group decreased significantly and the expression of anti-apoptotic protein Bcl-2 increased significantly(P<0.05).Conclusions:Zhuyu Annao pill can alleviateencephaledema for mice with ICH and reduce inflammatory responsesandnerve cell apoptosis.TLR4 can mediate inflammatory injury induced by ICH.Thus,Zhuyu Annao pill can play a protective role for brains by decreasing the expression of TLR4.

Negative Thermal Expansion of (ZrMg)xY2-2xMo3O12 Ceramics with Low Hygroscopicity

(ZrMg)xY2-2xMo3O12(x=0.0,0.1,0.2,0.3,0.4,0.5,0.6,0.7,0.8,0.9,and 1)ceramics have been synthesized to obtain less hygroscopicity and negative thermal expansion.With increasing the substitution of(ZrMg)^6+(ion radius 7.2×10^-11 m)for Y3+(ion radius 9×10^-11 m),the crystal water are reduced obviously.The linear thermal expansion coefficient is improved with increasing the content of(ZrMg)^6+.The material shows near zero thermal expansion(-0.12×10^-6 K^-1,430-870 K)with x=0.7.Meanwhile,ZrMgMo3O12 shows low non-hygroscopicity and negative thermal expansion,but low softening temperature.After substituting amount of Y^3+for(ZrMg)^6+in ZrMgMo3O12(x=0.8),the softening temperature increases remarkably(750 K to 830 K)and it presents near zero thermal expansion.

Spontaneous firing in olfactory bulb neurons of Bufo bufo gargarizans in and after hibernation

Microelectrode technique was used to record the spontaneous electrical activities of the neurons in olfactory bulb of the Bufo bufo gargarizans, both in hibernation and after hibemation. This study investigated the electrophysiological characteristics of amphibian olfactory bulb in the period of hibernation and after hibernation and its effects on the start of hibernation and spontaneous awakening. The research showed four forms of spontaneous firings： single spontaneous firing, burst spontaneous firing, irregular spontaneous firing and consecutive single spontaneous firing. The single spontaneous firing includes slow depolarized spontaneous firing and fast depolarized spontaneous firing, and the slow depolarized spontaneous firing occurs only during the hibernation period. In hibernation, the low amplitude and low frequency firing with a longer duration may be relevant to maintaining the tonicity of the central nervous system in toads that are in hibernation, and this kind of firing may also provide an excited basis for their arousal from hibernation. After hibernation, the amplitude and frequency of firing increase, but the firing duration gets shorter. This form of short-term firing, which may be a phenomenon of sensory neurons fast adapting, is one of the neuronal mechanisms for the arousal of hibernating animals.