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A Novel On-Site-Real-Time Method for Identifying Characteristic Parameters Using Ultrasonic Echo Groups and Neural Network

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 215-228页

作者： Shuyong Duan Jialin Zhang heng Ouyang xu Han Guirong liu State Key Laboratory of Reliability and Intelligence of Electrical Equipment Hebei University of TechnologyTianjin 300401China Department of Aerospace Engineering and Engineering Mechanics University of CincinnatiCincinnati 45221USA

On-site and real-time non-destructive measurement of elastic constants for materials of a component in a in-service structure is a challenge due to structural complexities,such as ambiguous boundary,variable thickness,nonuniform material properties.This work develops for the first time a method that uses ultrasound echo groups and artificial neural network(ANN)for reliable on-site real-time identification of material parameters.The use of echo groups allows the use of lower frequencies,and hence more accommodative to structural complexity.To train the ANNs,a numerical model is established that is capable of computing the waveform of ultrasonic echo groups for any given set of material properties of a given structure.The waveform of an ultrasonic echo groups at an interest location on the surface the structure with material parameters varying in a predefined range are then computed using the numerical model.This results in a set of dataset for training the ANN model.Once the ANN is trained,the material parameters can be identified simultaneously using the actual measured echo waveform as input to the ANN.Intensive tests have been conducted both numerically and experimentally to evaluate the effectiveness and accuracy of the currently proposed method.The results show that the maximum identification error of numerical example is less than 2%,and the maximum identification error of experimental test is less than 7%.Compared with currently prevailing methods and equipment,the proposefy the density and thickness,in addition to the elastic constants.Moreover,the reliability and accuracy of inverse prediction is significantly improved.Thus,it has broad applications and enables real-time field measurements,which has not been fulfilled by any other available methods or equipment.

关键词： Parameter identification Ultrasonic echo group High-precision modeling Artificial neural network NDT

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A proteomic landscape of pharmacologic perturbations for functional relevance

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Journal of Pharmaceutical Analysis 2024年第1期14卷 128-139页

作者： Zhiwei liu Shangwen Jiang Bingbing Hao Shuyu Xie Yingluo liu Yuqi Huang heng xu Cheng Luo Min Huang Minjia Tan Jun-Yu xu State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai201203China School of Chinese Materia Medica Nanjing University of Chinese MedicineNanjing210023China Zhongshan Institute for Drug Discovery Shanghai Institute of Materia MedicaChinese Academy of SciencesZhongshanGuangdong528400China State Key Laboratory of Pharmaceutical Biotechnology Nanjing UniversityNanjing210023China

Pharmacological perturbation studies based on protein-level signatures are fundamental for drug discovery. In the present study, we used a mass spectrometry (MS)-based proteomic platform to profile the whole proteome of the breast cancer MCF7 cell line under stress induced by 78 bioactive compounds. The integrated analysis of perturbed signal abundance revealed the connectivity between phenotypic behaviors and molecular features in cancer cells. Our data showed functional relevance in exploring the novel pharmacological activity of phenolic xanthohumol, as well as the noncanonical targets of clinically approved tamoxifen, lovastatin, and their derivatives. Furthermore, the rational design of synergistic inhibition using a combination of histone methyltransferase and topoisomerase was identified based on their complementary drug fingerprints. This study provides rich resources for the proteomic landscape of drug responses for precision therapeutic medicine.

关键词： Proteomics Drug Perturbation Drug target Drug combination

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Evaluation of erastin synergized cisplatin anti-nasopharyngeal carcinoma effect with a glutathione-activated near-infrared fluorescent probe

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Chinese Chemical Letters 2024年第2期35卷 311-316页

作者： Rong He Dandan Tang Ningge xu heng liu Kun Dou xuejun Zhou Fabiao Yu Department of Otolaryngology Head and Neck SurgeryThe First Affiliated Hospital of Hainan Medical UniversityHaikou 570102China Key Laboratory of Hainan Trauma and Disaster Rescue Key Laboratory of Emergency and TraumaMinistry of EducationEngineering Research Center for Hainan Bio-Smart Materials and Bio-Medical DevicesCollege of Emergency and TraumaHainan Medical UniversityHaikou 571199China Sichuan Provincial General Hospital of Judicial Police Chengdu 610225China

Nasopharyngeal carcinoma(NPC),a malignant tumor originating from the nasopharynx,is one of the common malignant tumors of the head and neck.There are significant geographical differences in the incidence of nasopharyngeal carcinoma,with a high incidence in China and Southeast Asian countries.Herein,we designed and synthesized a novel near-infrared fluorescent(NIRF)probe to detect glutathione(GSH)in cellular and tumor environments using semi-naphthofluorescein(SNAFL)as the fluorescent molecular backbone and 2-fluoro-4-nitrobenzenesulfonate as the recognition moiety.Upon reaction with GSH,SNAFL-GSH emitted a fluorescence signal,and its emission wavelength at 650 nm was remarkably enhanced.The results of selectivity experiments indicated that SNAFL-GSH was able to discriminate GSH from Cys,Hcy,and H_(2) S.Moreover,SNAFL-GSH could image both endogenous and exogenous GSH and distinguish normal and cancer cells by fluorescence signal difference.At the cellular level,cisplatin(DDP)-induced ferroptosis and inhibition of proliferation of various NPC cell lines(CNE2,CNE1,5-8F cells)by erastin combined with DDP were visualized with the help of SNAFL-GSH.In a mouse tumor xenograft model,we successfully employed SNAFL-GSH for the evaluation of the efficacy of erastin combined with DDP in the treatment of NPC.More importantly,the probe could image cancerous tissue sections from NPC patients with an imaging depth of approximately 80µm.It was foreseen that SNAFL-GSH offered great potential for application in the diagnosis and evaluation of the therapeutic efficacy of NPC,and these results would also provide new ideas for the clinical treatment of NPC.

关键词： Glutathione NIRF probe Ferroptosis Anti-tumor therapy evaluation Bioimaging

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Riverine sulfate sources and behaviors in arid environment,Northwest China:Constraints from sulfur and oxygen isotopes

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Journal of Environmental Sciences 2024年第3期137卷 716-731页

作者： Yifu xu Wenjing liu Bing xu Zhifang xu Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

The fate of riverine sulfate ion (SO_(4)^(2-)) and its environmental effects in arid environment are difficult to evaluate due to its complicated sources and strongly coupled behaviors with water cycle which is significantly modified by humans.To understand the sulfur cycle in aquatic systems in arid environment,the chemical and sulfur and oxygen isotopic compositions (δ^(34)S_(SO4)and δ^(18)O_(SO4)) of major rivers around the Badain Jaran Desert,northwestern China,were investigated.These rivers had averaged SO_(4)^(2-)content at 1336μmol/L,over 10times higher than the global average.The δ^(34)S_(SO4)and δ^(18)O_(SO4)values ranged from-5.3‰to+11.8‰and+1.6‰to+12.8‰,respectively.The end-member analysis and the inverse model showed that riverine sulfate was mainly derived from evaporites dissolution (0-87%),sulfide oxidation (13%-100%) and precipitation (0-33%),indicating heterogeneity in sulfur sources and behaviors along the river drainage with the lithology variations and climate gradients.Multiple isotopic tools combining with hydro-chemistry compositions could be applied to reveal sulfur cycle in arid environment.Based on the calculation,sulfide oxidation plays the primary role in the headwater and upstream in the Qilian-Mountains area,where sulfide is widely exposed.While the proportion of evaporites dissolution contributing to riverine sulfate is much higher in downstream in a drier environment.Besides,less precipitation and higher temperature can lead to more intensive evaporation,affecting the process of sulfide oxidation and enhancing the rates of evaporites dissolution and sulfate precipitation in the basin.

关键词： Sulfur and oxygen isotopes Source apportionment Inverse model Arid environment Inland rivers Northwestern China

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Assessment of tree-ring mercury radial translocation and age effect in Masson pine:Implications for historical atmospheric mercury reconstruction

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Journal of Environmental Sciences 2024年第4期138卷 266-276页

作者： xu liu xun Wang Dingyong Wang College of Resources and Environment Southwest UniversityChongqing 400715China State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China

The tree ring has been regarded as an emerging archive to reconstruct historical atmospheric mercury(Hg)trends,but with the large knowledge gaps in the reliability.In this study,we comprehensively evaluated the Hg source,radial translocation and age effect of Masson pine(Pinus massoniana)tree ring at Mt.Jinyun in Chongqing,to assess the suitability of such tree ring as the archive of atmospheric Hg.Results showed that distinct variabilities among Masson pine tree-ring Hg concentration profiles.The Hg concentration significantly increased along with stem height(P<0.05),indicating the Hg in tree rings mainly derived from foliage uptake atmospheric Hg.We found a distinct age effect that the tree ring of young trees had the higher Hg concentration.Besides,we used the advection-diffusion model to demonstrate how Hg concentration shifted by the advection or/and diffusion in tree rings.The modeling results showed that the advection induced radial translocation during the young growth period of tree was a plausible mechanism to result in the tree-ring Hg record largely different from the trend of anthropogenic Hg emissions in Chongqing.We finally suggest that in further Hg dendrochemistry,better discarding the tree-ring Hg profile of the young growth period to reduce impacts of the radial translocation and age effect.

关键词： Masson pine Tree-ring mercury Radial translocation Tree age effect

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Strategies for improving extraction capacity through preorganization structure:A novel 5,6-bicyclicmalonamide extractant(THPPD)

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Journal of Rare Earths 2024年第4期42卷 768-774页

作者： Miaomiao Zhang Zhen Yang Yuhua Cui Jianhui Su heng Zhao Chengjin xu Xiaolei liu Guoxin Sun Xiujing Peng Yu Cui School of Chemistry and Chemical Engineering University of JinanJinan250022China Institute for Smart Materials&Engineering University of JinanJinan250022China Shandong Institute for Food and Drug Control Jinan250101China

Rational design of extractant structure to improve the extraction and separation capacity of rare earth elements(REEs)is a long-standing challenge.Herein,a new strategy was proposed to improve the stability of the chelating structure formed by malonamide and REEs.The stability of the chelating structure is greatly improved by using a double-ring framework structure which makes the two carbonyl groups of malonamide unable to rotate freely and both of them point to the metal ion position.Three benzyl groups were used to construct the hydrophobicity of the extractant and the organic shell of the extracted species.Tribenzylhexahydro-pyrrolo-pyridine-dione(THPPD)was designed and synthesized.The structure reduces the energy consumed by rotating carbonyl group in the coordination with metal ions and then improves the extraction ability of extractant.The crystal structure was preorganized as expected,with the two carbonyls pointing in a favorable coordination direction to the structural complement of the metal ion.The extraction behaviors of REEs with THPPD in a nitric acid medium were studied.Compared with N,N’-dibenzyl-N,N’-dimethylmalonamide(DBDM-MA)with a chain structure,the extraction capacity of THPPD is 360 times higher than that of DBDM-MA at 5.0 mol/L sodium nitrate.Furthermore,the binding energy and Gibbs free energy were investigated by density functional theory(DFT)in conjunction with the B3LYP.The theoretical results show that THPPD has more effective interaction with Pr(NO_(3))3 than DBDM-MA.The construction of chelating groups conformation is a worthy direction to improve the coordination ability and even selectivity of extractant.

关键词： Rare earth elements Extraction separation 5,6-bicyclicdiamide extractant

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Study on Catalytic Behavior of Iron-based Catalyst with IITP as Electron Donor in the Polymerization of Butadiene

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Chinese Journal of Polymer Science 2024年第5期42卷 612-619,I0007页

作者： Shi-Liang xu Ying-Nan Zhao Yao Yu Qi Yang Li-Hua Na heng liu Chun-Yu Zhang xue-Quan Zhang Key Laboratory of Advanced Rubber Material Ministry of EducationSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China Shandong Provincial College Laboratory of Rubber Material and Engineering School of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China Key Lab of Rubber-Plastics Ministry of Education/Shandong Provincial Key Lab of Rubber-plasticsSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China

In this study,a novel iron-based catalyst system,Fe(acac)3/(isocyanoimino)triptenylphosphorane(IITP)/AlR3,was employed for the synthesis of syndiotactic 1,2-polybutadiene in hexane.This catalyst system exhibits remarkably high catalytic activity,achieving a polymerization activity of 762 kgpolymer·molcatalyst^(-1)·h^(-1)at 50℃with a[BD]/[Fe]molar ratio of 20000.Furthermore,living polymerization characteristic were observed during the investigation of the polymerization kinetics of 1,3-butadiene polymerization.These characteristics were well demonstrated by a narrow molecular weight distribution(PDI≈2.0)of the resulting polybutadiene and a linear relationship between-ln(1-c)and polymerization time as well as number average molecular weight and polymer yield.The resultant polymer showed a 1,2-selectivity of approximately 76%and stereoregularity ranging from 62%to 73%(rrrr).Additionally,through kinetic studies on polymerization reaction,an apparent activation energy Ea value of this catalytic system was calculated to be 84.98 kJ·mol^(-1),which suggests that high polymerization temperature favors efficient polymerization.

关键词： Iron catalyst Syndiotactic 1,2-polybutadiene Elastomers Donor Selectivity

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Mannitol inhibits the proliferation of neural stem cell by a p38 mitogen-activated protein kinase-dependent signaling pathway

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Chinese Journal of Traumatology 2024年第1期27卷 42-52页

作者： Hai-Zhen Duan Xin Zhou Quan Hu Meng-Long liu Shu-Hong Wang Ji Zhang xu-heng Jiang Tian-Xi Zhang An-Yong Yu Department of Emergency Affiliated Hospital of Zunyi Medical UniversityZunyi563000Guizhou provinceChina Dazhou Vocational College of Chinese Medicine Dazhou635000Sichuan provinceChina Dachuan District Traditional Chinese Medicine Hospital Dazhou635000Sichuan provinceChina

Purpose:Mannitol is one of the first-line drugs for reducing cerebral edema through increasing the extracellular osmotic pressure.However,long-term administration of mannitol in the treatment of cerebral edema triggers damage to neurons and astrocytes.Given that neural stem cell(NSC)is a subpopulation of main regenerative cells in the central nervous system after injury,the effect of mannitol on NSC is still elusive.The present study aims to elucidate the role of mannitol in NSC proliferation.Methods:C57 mice were derived from the animal house of Zunyi Medical University.A total of 15 pregnant mice were employed for the purpose of isolating NSCs in this investigation.Initially,mouse primary NSCs were isolated from the embryonic cortex of mice and subsequently identified through immunofluorescence staining.In order to investigate the impact of mannitol on NSC proliferation,both cell counting kit-8 assays and neurospheres formation assays were conducted.Thein vitro effects of mannitol were examined at various doses and time points.In order to elucidate the role of Aquaporin 4(AQP4)in the suppressive effect of mannitol on NSC proliferation,various assays including reverse transcription polymerase chain reaction,western blotting,and immunocytochemistry were conducted on control and mannitol-treated groups.Additionally,the phosphorylated p38(p-p38)was examined to explore the potential mechanism underlying the inhibitory effect of mannitol on NSC proliferation.Finally,to further confirm the involvement of the p38 mitogen-activated protein kinase-dependent(MAPK)signaling pathway in the observed inhibition of NSC proliferation by mannitol,SB203580 was employed.All data were analyzed using SPSS 20.0 software(SPSS,Inc.,Chicago,IL).The statistical analysis among multiple comparisons was performed using one-way analysis of variance(ANOVA),followed by Turkey’’s post hoc test in case of the data following a normal distribution using a Shapiro-Wilk normality test.Comparisons between 2 groups were determined using Student’s t-te

关键词： Mannitol Cerebral edema Neural stem cell Proliferation AQP4 p38 MAPK signaling pathway

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A stable staggered-grid finite-difference scheme for acoustic modeling beyond conventional stability limit

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Petroleum Science 2024年第1期21卷 182-194页

作者： Jing-Yi xu Yang liu National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing 102249China China University of Petroleum(Beijing) Karamay CampusKaramay 834000XinjiangChina

Staggered-grid finite-difference(SGFD)schemes have been widely used in acoustic wave modeling for geophysical problems.Many improved methods are proposed to enhance the accuracy of numerical modeling.However,these methods are inevitably limited by the maximum Courant-Friedrichs-Lewy(CFL)numbers,making them unstable when modeling with large time sampling intervals or small grid spacings.To solve this problem,we extend a stable SGFD scheme by controlling SGFD dispersion relations and maximizing the maximum CFL numbers.First,to improve modeling stability,we minimize the error between the FD dispersion relation and the exact relation in the given wave-number region,and make the FD dispersion approach a given function outside the given wave-number area,thus breaking the conventional limits of the maximum CFL number.Second,to obtain high modeling accuracy,we use the SGFD scheme based on the Remez algorithm to compute the FD coefficients.In addition,the hybrid absorbing boundary condition is adopted to suppress boundary reflections and we find a suitable weighting coefficient for the proposed scheme.Theoretical derivation and numerical modeling demonstrate that the proposed scheme can maintain high accuracy in the modeling process and the value of the maximum CFL number of the proposed scheme can exceed that of the conventional SGFD scheme when adopting a small maximum effective wavenumber,indicating that the proposed scheme improves stability during the modeling.

关键词： Acoustic wave Staggered-grid finite-difference(SGFD) modeling Courant-friedrichs-lewy(CFL)number Stability

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Incidence,prevalence,and causes of spinal injuries in China,1990-2019:Findings from the Global Burden of Disease Study 2019

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Chinese Medical Journal 2024年第6期137卷 704-710页

作者： Chenjun liu Tingling xu Weiwei Xia Shuai xu Zhenqi Zhu Maigeng Zhou Haiying liu Department of Spinal Surgery Peking University People’s HospitalPeking UniversityBeijing 100044China Chinese Preventive Medicine Association Committee on Prevention and Control of Spinal DiseaseBeijing 100009China National Center for Chronic and Noncommunicable Disease Control and Prevention Chinese Center for Disease Control and PreventionBeijing 100050China School of Public Health Xi’an Jiaotong UniversityXi’anShaanxi 710061China

Background:Spinal injuries are an urgent public health priority;nevertheless,no China-wide studies of these injuries exist.This study measured the incidence,prevalence,causes,regional distribution,and annual trends of spinal injuries in China from 1990 to 2019.Methods:We used data from the Global Burden of Diseases,Injuries,and Risk Factors Study 2019 to estimate the incidence and prevalence of spinal injuries in China.The data of 33 provincial-level administrative regions(excluding Taiwan,China)provided by the National Center for Chronic and Noncommunicable Disease Control and Prevention,Chinese Center for Disease Control and Prevention(CDC)were use to systematically analyze the provincial etiology,geographical distribution,and annual trends of spinal injuries.The Bayesian meta-regression tool DisMod-MR 2.1 was used to ensure the consistency among incidence,prevalence,and mortality rates in each case.Results:From 1990 to 2019,the number of living patients with spinal injuries in China increased by 138.32%,from 2.14 million to 5.10 million,while the corresponding age-standardized prevalence increased from 0.20%(95%uncertainty interval[UI]:0.18-0.21%)to 0.27%(95%UI:0.26-0.29%).The incidence of spinal injuries in China increased by 89.91%(95%UI:72.39-107.66%),and the prevalence increased by 98.20%(95%UI:89.56-106.82%),both the most significant increases among the G20 countries;71.00%of the increase could be explained by age-specific prevalence.In 2019,the incidence was 16.47(95%UI:12.08-22.00,per 100,000 population),and the prevalence was 358.30(95%UI:333.96-386.62,per 100,000 population).Based on the data of 33 provincial-level administrative regions provided by CDC,age-standardized incidence and prevalence were both highest in developed provinces in Eastern China.The primary causes were falls and road injuries;however,the prevalence and specific causes differed across provinces.Conclusions:In China,the overall disease burden of spinal injuries increased significantly during the past three decades but varied consi

关键词： Spinal injuries Global Burden of Diseases,Injuries and Risk Factors Study 2019 Incidence Prevalence Falls Road injuries

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