Nondestructive technique for identifying nuclides using neutron resonance transmission analysis at CSNS Back-n

Nondestructive and noninvasive neutron assays are essential applications of neutron techniques.Neutron resonance transmission analysis(NRTA)is a powerful nondestructive method for investigating the elemental composition of an object.The back-streaming neutron line(Back-n)is a newly built time-of-flight facility at the China Spallation Neutron Source(CSNS)that provides neutrons in the eV to 300 MeV range.A feasibility study of the NRTA method for nuclide identification was conducted at the CSNS Back-n via two test experiments.The results demonstrate that it is feasible to identify different elements and isotopes in samples using the NRTA method at Back-n.This study reveals its potential future applications.

In-beam gamma rays of CSNS Back-n characterized by black resonance filter

The back-streaming white-neutron beamline(Back-n)of the China Spallation Neutron Source is an essential neutronresearch platform built for the study of nuclear data,neutron physics,and neutron applications.Many types of cross-sectional neutron-reaction measurements have been performed at Back-n since early 2018.These measurements have shown that a significant number of gamma rays can be transmitted to the experimental stations of Back-n along with the neutron beam.These gamma rays,commonly referred to as in-beam gamma rays,can induce a non-negligible experimental background in neutron-reaction measurements.Studying the characteristics of in-beam gamma rays is important for understanding the experimental background.However,measuring in-beam gamma rays is challenging because most gamma-ray detectors are sensitive to neutrons;thus,discriminating between neutron-induced signals and those from in-beam gamma rays is difficult.In this study,we propose the use of the black resonance filter method and a CeBr_(3) scintillation detector to measure the characteristics of the in-beam gamma rays of Back-n.Four types of black resonance filters,^(181)Ta,^(59)Co,^(nat)Ag,and^(nat)Cd,were used in this measurement.The time-of-flight(TOF)technique was used to select the detector signals remaining in the absorption region of the TOF spectra,which were mainly induced by in-beam gamma rays.The energy distribution and flux of the in-beam gamma rays of Back-n were determined by analyzing the deposited energy spectra of the CeBr_(3) scintillation detector and using Monte Carlo simulations.Based on the results of this study,the background contributions from in-beam gamma rays in neutron-reaction measurements at Back-n can be reasonably evaluated,which is beneficial for enhancing both the experimental methodology and data analysis.

Risk of cardiovascular death in patients with hepatocellular carcinoma based on the Fine-Gray model

BACKGROUND Hepatocellular carcinoma(HCC)is one of the most common types of cancers worldwide,ranking fifth among men and seventh among women,resulting in more than 7 million deaths annually.With the development of medical tech-nology,the 5-year survival rate of HCC patients can be increased to 70%.How-ever,HCC patients are often at increased risk of cardiovascular disease(CVD)death due to exposure to potentially cardiotoxic treatments compared with non-HCC patients.Moreover,CVD and cancer have become major disease burdens worldwide.Thus,further research is needed to lessen the risk of CVD death in HCC patient survivors.METHODS This study was conducted on the basis of the Surveillance,Epidemiology,and End Results database and included HCC patients with a diagnosis period from 2010 to 2015.The independent risk factors were identified using the Fine-Gray model.A nomograph was constructed to predict the CVM in HCC patients.The nomograph performance was measured using Harrell’s concordance index(C-index),calibration curve,receiver operating characteristic(ROC)curve,and area under the ROC curve(AUC)value.Moreover,the net benefit was estimated via decision curve analysis(DCA).RESULTS The study included 21545 HCC patients,of whom 619 died of CVD.Age(<60)[1.981(1.573-2.496),P<0.001],marital status(married)[unmarried:1.370(1.076-1.745),P=0.011],alpha fetoprotein(normal)[0.778(0.640-0.946),P=0.012],tumor size(≤2 cm)[(2,5]cm:1.420(1.060-1.903),P=0.019;>5 cm:2.090(1.543-2.830),P<0.001],surgery(no)[0.376(0.297-0.476),P<0.001],and chemotherapy(none/unknown)[0.578(0.472-0.709),P<0.001]were independent risk factors for CVD death in HCC patients.The discrimination and calibration of the nomograph were better.The C-index values for the training and validation sets were 0.736 and 0.665,respectively.The AUC values of the ROC curves at 2,4,and 6 years were 0.702,0.725,0.740 in the training set and 0.697,0.710,0.744 in the validation set,respectively.The calibration curves showed that the predicted probab-ilities of the CVM prediction model in the training set vs the validation set were largely consistent with the actual probabilities.DCA demonstrated that the prediction model has a high net benefit.CONCLUSION Risk factors for CVD death in HCC patients were investigated for the first time.The nomograph served as an important reference tool for relevant clinical management decisions.

Measurement of the ^(232)Th(n,f)cross section in the 1-200 MeV range at the CSNS Back-n

The ^(232)Th(n,f)cross section is very important in basic nuclear physics and applications based on the Th/U fuel cycle.Using the time-of-flight method and a multi-cell fast-fission ionization chamber,a novel measurement of the^(232)Th(n,f)cross sec-tion relative to^(235)U in the 1–200 MeV range was performed at the China Spallation Neutron Source Back-n white neutron source(Back-n).The fission event-neutron energy spectra of^(232)Th and^(235)U fission cells were measured in the single-bunch mode.Corrected 232Th/235U fission cross-sectional ratios were obtained,and the measurement uncertainties were 2.5–3.7%for energies in the 2–20 MeV range and 3.6–6.2%for energies in the 20–200 MeV range.The^(232)Th(n,f)cross section was obtained by introducing the standard cross section of^(235)U(n,f).The results were compared with those of previous theoreti-cal calculations,measurements,and evaluations.The measured 232Th fission cross section agreed with the main evaluation results in terms of the experimental uncertainty,and 232Th fission resonances were observed in the 1–3 MeV range.The present results provide^(232)Th(n,f)cross-sectional data for the evaluation and design of Th/U cycle nuclear systems.

Study on prescription medication mode and mechanism of traditional Chinese medicine in the treatment of noncritical COVID-19 based on data mining

Background:As of 2023,coronavirus disease 2019(COVID-19)is still spreading globally.Therefore,we aim to integrate non-critical COVID-19 high-frequency and high-targeting Chinese medicines to provide a reference for clinical prescriptions to improve COVID-19-related symptoms.Materials and methods:The information on non-critical COVID-19 high-frequency Chinese medicines in the diagnosis and treatment of COVID-19 was obtained by the TCM inheritance support platform.Using network pharmacology and molecular docking technology,high-targeting Chinese medicines with good docking activity with COVID-19 receptors angiotensin-converting enzyme-II(ACE2),3CLpro and tyrosine-protein kinase receptor UFO(AXL)were obtained.A new prescription for non-critical COVID-19 was established by integrating high-frequency and high-targeting Chinese medicines.Rats with acute lung injury induced by lipopolysaccharide were used as the experimental model.The histopathological changes in the lungs of rats in each group were observed by hematoxylin-eosin staining.The lung coefficient of rats was measured.The levels of IL-6,TNF-α,and IL-1βin serum were detected by enzyme-linked immunosorbent assay.The mRNA and protein levels of ACE2 and AXL in lung tissue were detected by real-time quantitative polymerase chain reaction and western blot.Results:Through data mining,it was found that there were 39 high-frequency traditional Chinese medicines for non-critical COVID-19 in the diagnosis and treatment guidelines.According to network pharmacology and molecular docking,30 highly targeted traditional Chinese drugs for COVID-19 were found.The new prescriptions for non-critical COVID-19 were comprehensively obtained,including Glycyrrhizae Radix,Ephedra Herba,Amygdalus Communis Vas,Gypsum Fibrosum,Descurainiae Semen,Atractylodes Lancea,Scutellariae Radix,Amomum Tsao-Ko Crevostet,Forsythiae Fructus,Pogostemon cablin,Magnolia Officinalis.Compared with the LPS-induced lung injury model group,the medium dose of the new prescription group had significantly alleviated pathological changes in lung tissue,decreased lung coefficient,decreased contents of IL-6,TNF-αand IL-1β,and increased mRNA and protein expression of ACE2 and AXL(P<0.05).Conclusion:Based on data mining,network pharmacology and molecular docking technology,the new prescription for non-critical COVID-19 established by this method has an anti-inflammatory effect on rats with acute lung injury induced by lipopolysaccharide and can provide a reference for clinicians to alleviate the symptoms related to non-critical COVID-19.

Back-n white neutron source at CSNS and its applications

Back-streaming neutrons from the spallation target of the China Spallation Neutron Source(CSNS)that emit through the incoming proton channel were exploited to build a white neutron beam facility(the so-called Back-n white neutron source),which was completed in March 2018.The Back-n neutron beam is very intense,at approximately 29107 n/cm2/s at 55 m from the target,and has a nominal proton beam with a power of 100 kW in the CSNS-I phase and a kinetic energy of 1.6 GeV and a thick tungsten target in multiple slices with modest moderation from the cooling water through the slices.In addition,the excellent energy spectrum spanning from 0.5 eV to 200 MeV,and a good time resolution related tothe time-of-flight measurements make it a typical white neutron source for nuclear data measurements;its overall performance is among that of the best white neutron sources in the world.Equipped with advanced spectrometers,detectors,and application utilities,the Back-n facility can serve wide applications,with a focus on neutron-induced cross-sectional measurements.This article presents an overview of the neutron beam characteristics,the experimental setups,and the ongoing applications at Backn.

Measurement of the neutron total cross section of carbon at the Back-n white neutron beam of CSNS

To verify the performance of the neutron total cross-sectional spectrometer, the neutron total cross section of carbon is initially measured in the energy range of 1 eV to 20 MeV using the time-of-flight method. The measurement is performed at the Back-n white neutron source with a 76-m time-of-flight path using the China Spallation Neutron Source. A multilayer fast fission chamber with 235U and 238U is employed as the neutron detector. The diameter and thickness of the natural graphite sample are 70 mm and 40 mm, respectively. Signal waveforms are collected using a data acquisition system. Off-line data processing was used to obtain the neutron time-of-flight spectra and transmissions. The uncertainty of the counting statistics is generally approximately 3% for each bin in the energy range of 1–20 MeV. It is determined that the results for the neutron total cross section of carbon obtained using ^235U cells are in good agreement with the results obtained using 238U cells within limits of statistical uncertainty. Moreover, the measured total cross sections show good agreement with the broadening evaluated data.

Efficacy of Xuebijing injection for the treatment of coronavirus disease 2019 via network pharmacology

Background:To evaluate the mechanism of Chinese patent drug Xuebijing(XBJ)injection in the treatment of a new coronavirus disease 2019(COVID-19)based on network pharmacology and molecular docking technology.Methods:The TCMSP database was employed to collect and screen the active ingredients of the Chinese herb contained in the XBJ injection.The GeneCards database and STRING database were applied to collect and expand the targets of COVID-19 and compare and screen the related targets of COVID-19 by XBJ injection.Cytoscape was employed to build a network connecting Chinese medicine,compounds,targets,disease,and topology analysis was performed via the Network Analyzer to screen the key ingredients and targets.The software of Schrödinger molecular docking was used to verify the binding activity of the key ingredients of XBJ injection and the key targets of COVID-19.Metascape platform and DAVID database were utilized to conduct Gene Ontology analysis and Kyoto Encyclopedia of Genes and Genomes analysis on the key targets of COVID-19 treated by XBJ injection.Results:Eight key compounds and 15 key targets were screened and verified by molecular docking;these key compounds included luteolin,quercetin,baicalein,and kaempferol.The key targets included DPP4,AR,ESR1,CALM1,and protein kinase 1.Gene Ontology analysis involved an apoptosis and hypoxia reaction and the changes in blood vessel morphology.Kyoto Encyclopedia of Genes and Genomes analysis involved signaling pathways of hypoxia inducible factor-1,VEGF,and PI3K/AKT/NF-κB.Conclusion:The mechanism of XBJ injection when used to treat COVID-19 should be further investigated as the key compounds in XBJ regulated the expression of key targets such as protein kinase 1,VEGF-A,B-cell lymphoma-2,and TNF,which affected the COVID-19 receptors such as angiotensin-converting enzyme 2 and signaling pathways like hypoxia inducible factor-1,PI3K-Akt,and NF-κB,which alleviated the inflammation,respiratory distress,and hypoxia caused by COVID-19 infection.

Nonlocal effect on resonant radiation force exerted on semiconductor coupled quantum well nanostructures

Based on the microscopic nonlocal optical response theory, the resonant radiation force exerted on a semiconductorcoupled quantum well nanostructure(CQWN), induced by the nonlocal interaction between lasers and electrons in conduction bands, is investigated for two different polarized states. The numerical results show that the spatial nonlocality of optical response can cause a radiation shift(blue-shift) for the spectrum of the resonant radiation force, which is dependent on the CQWN width ratio, the barrier height, and polarized states sensitively. It is also confirmed that the resonant radiation force is steerable by the incident and polarized directions of incident light. This work may provide an advantageous method for detecting internal quantum properties of nanostructures, and open novel and raising possibilities for optical manipulation of nano-objects using laser-induced radiation force.

Human Papillomavirus Type 16 Mutant E7 Protein Induces Oncogenic Transformation via Up-regulation of Cyclin A and cdc25A

A new mutant human papillomavirus type 16 E7 gene, termed HPV16 HBE7, was isolated from cervical carcinoma biopsy samples from patients in an area with high incidence of cervical cancer (Hubei province, China). A previous study showed that the HPV16 HBE7 protein was primarily cytoplasmic while wild-type HPV16 E7 protein, termed HPV16 WE7, was concentrated in the nucleus. With the aim of studying the biological functions of HPV16 HBE7, the transforming potential of HPV16 HBE7 in NIH/3T3 cells was detected through observation of cell morphology, cell proliferation assay and anchorage-independent growth assay. The effect of HPV16 HBE7 on cell cycle was examined by flow cytometry. Dual-luciferase reporter assay and RT-PCR were used to investigate the influence of HPV16 HBE7 protein on the expression of regulation factors associated with G1/S checkpoint. The results showed that HPV16 HBE7 protein, as well as HPV16 WE7 protein, held transformation activity. NIH/3T3 cells expressing HPV16 HBE7 could easily transition from G1 phase into S phase and expressed high level of cyclin A and cdc25A. These results indicated HPV16 mutant E7 protein, located in the cytoplasm, induces oncogenic transformation of NIH/3T3 cells via up-regulation of cyclin A and cdc25A.

Treating COVID-19 by traditional Chinese medicine:a charming strategy?

On April 14,2020,the State Council of China announced that“three proprietary Chinese medicines and three decoctions”of effective traditional Chinese medicine(TCM)in the treatment of the novel coronavirus pneumonia have passed clinical practice screenings[1].Some scholars believe that early TCM intervention of mild and moderate cases and recovery period may reduce the ratio of mild cases progressing into severe and critical cases.Some data have also suggested that the combination of TCM and Western medicine may reduce the mortality rate in severe and critical cases[2,3].

Meta-analysis of Tonifying-Kindney and Soothing-Liver traditional Chinese medicine method in the treatment of polycystic ovary syndrome

Background:To systematically evaluate the clinical efficacy of Tonifying-Kindney and Soothing-Liver method in the treatment of polycystic ovary syndrome(PCOS).Methods:The literatures of randomized controlled trials(RCTs)on the treatment of PCOS with traditional Chinese medicine(TCM)published at home and abroad until March 2020 were retrieved,and RCTs on the treatment of PCOS with Tonifying-Kindney and Soothing-Liver method were collected.According to the systematic evaluation method of the Cochrane Collaboration Network,RevMan5.3 software was used to perform quality evaluation and data extraction for meta-analysis of tests that met the inclusion criteria.Results:A total of 30 eligible RCTs were included,including 2244 patients.Meta-analysis results show that the method of tonifying the kidney and Soothing-Liver has certain advantages in the treatment of PCOS.Compared with Western medicine alone group,tonifying the kidney and Soothing-Liver TCM method alone or combined with Western medicine could improve the total effective rate[OR=3.52,95%CI(2.67,4.63),I2=0%,P<0.00001].It is superior to the control group in improving ovulation rate[OR=2.01,95%CI(1.46,2.78),I2=0%,P<0.0001],pregnancy rate[OR=2.82,95%CI(2.28,3.49),I2=0%,P<0.00001],reducing LH[MD=-2.65,95%CI(-3.43,-1.88),I2=92%,P<0.00001]and ovarian stimulating hormone levels[MD=-0.52,95%CI(-0.85,-0.18),I2=94%,P=0.002].There was no statistical difference in reducing serum testosterone levels[SMD=-0.56,95%CI(-1.22,0.09),I2=96%,P=0.09]and improving TCM symptoms[MD=-0.09,95%CI(-4.75,4.56),I2=97%,P=0.97].Conclusion:The method of tonifying the kidney and Soothing-Liver has a certain effect in treating polycystic ovary syndrome,but the evidence is still very limited,and a large sample of high-quality randomized controlled studies is still needed in order to make a more rigorous evaluation.

Acupuncture combined with modern rehabilitation therapy for post-stroke flaccid paralysis

Stroke has been in a high incidence,and stroke sequelae have become the main cause of motor dysfunction.The treatment of flaccid paralysis is critical to stroke recovery.In recent years,traditional treatment,especially acupuncture therapy has achieved certain effects for the treatment of post-stroke flaccid paralysis.Acupuncture treatment can promote the recovery of nerve conduction,increase muscle strength and improve joint flexibility,and correct abnormal movement patterns of limbs.Acupuncture combined with rehabilitation training will be the focus for the treatment of post-stroke flaccid paralysis.In this review,the combination of different acupuncture therapies with modern rehabilitation for the treatment of post-stroke flaccid paralysis has been summarized in order to effectively promote the recovery of motor function and significantly improve their life quality.

A network pharmacology approach to investigate the mechanism of“Huangqi-Shanzhuyu”in the treatment of diabetic nephropathy

Background:To explore the action mechanism of Huangqi(Radix Astragali)and Shanzhuyu(Fructus Corni)in the treatment of diabetic nephropathy based on network pharmacology,aiming to provide a basis for clinical application.Methods:The main active components of Huangqi and Shanzhuyu were discerned through the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP),Traditional Chinese Medicine Integrated Database(TCMID).The targets related to diabetic nephropathy(DN)were obtained using Genecards,Therapeutic Target Database(TTD),and National Center for Biotechnology Information(NCBI)Gene.Subsequently,protein-protein interaction(PPI)networks were constructed with Cytoscape 3.7.2 and the STRING database.Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analyses were performed to analyze the intersection of targets via Database for Annotation,Visualization,and Integrated Discovery(DAVID)6.8.Built on the above analysis,we made a“Chinese medicine-chemical composition-target gene-disease”network.Results:Twenty-one active components were predicted from the Huangqi and Shanzhuyu herb pair,such as jaranol,mandenol and sitosterol.These components were applied to 41 targets mainly involved in many biological processes such as the PI3K-Akt signaling pathway,vascular endothelial growth factor(VEGF)signaling pathway,regulation of sodium ion transport and steroid-binding.Conclusion:This study proposes the network pharmacology method and identifies the potent combination therapeutic mechanism of Huangqi and Shanzhuyu for diabetic nephropathy(DN)through multiple targets and routes,this strategy will lay a good foundation for further in-depth study of the mechanism of action.

Enhanced strength and electrical conductivity of Al-0.3Ce alloy simultaneously with Ti(C,N)nanoparticle addition

Ti(C,N)nanoparticles were added to an Al-0.3 Ce alloy by ultrasonic treatment.Further annealing at 570℃for4 h afforded the ultimate tensile strength of 79 MPa and electrical conductivity of 64.0%IACS for the Al-0.3 Ce alloy with1.5 vol%Ti(C,N)addition.Both performance parameters were improved by 23.4%and 0.6%IACS,respectively,compared with those of casting refining pure aluminum(64 MPa and63.4%IACS).This could be explained by the following reasons.The addition of Ti(C,N)nanoparticles could significantly refine the grain of Al-0.3 Ce alloy.Notably,most of the coarse strip-shaped second phases distributed at the grain boundaries in Al-0.3 Ce were also transformed into spherical microparticles distributed in the grains,with micro-nano hierarchical structures comprising orientated nanosized strip phases with lengths of~400 nm and widths of~100 nm.Moreover,a fine micro-nano hierarchical spherical structure could be obtained after annealing at 570℃for 4 h.The numbers of micro-nano hierarchical spherical structures also increased due to the precipitation of pseudosolution Ce from the aluminum matrix during the annealing treatment.