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Optimization Design of the Multi-Layer Cross-Sectional Layout of An Umbilical Based on the GA-GLM

China Ocean Engineering 2024年第2期38卷 247-254页

作者： YANG Zhi-xun YIN Xu FAN Zhi-rui YAN Jun LU yu-cheng SU qi MAO Yandong WANG Hua-lin Institute of marine machinery College of Mechanical and Electrical EngineeringHarbin Engineering UniversityHarbin 150001China State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentDepartment of Engineering MechanicsDalian University of TechnologyDalian 116024China Ningbo Institube of Dalian University of Technology Ningbo 315040China

Marine umbilical is one of the key equipment for subsea oil and gas exploitation,which is usually integrated by a great number of different functional components with *** layout of these components directly affects manufacturing,operation and storage performances of the *** the multi-layer cross-sectional layout design of the umbilical,a quantifiable multi-objective optimization model is established according to the operation and storage *** the manufacturing factors,the multi-layering strategy based on contact point identification is introduced for a great number of functional ***,the GA-GLM global optimization algorithm is proposed combining the genetic algorithm and the generalized multiplier method,and the selection operator of the genetic algorithm is improved based on the steepest descent *** algorithm is used to find the optimal solution in the global space,which can converge from any initial layout to the feasible layout *** feasible layout solution is taken as the initial value of the generalized multiplier method for fast and accurate ***,taking umbilicals with a great number of components as examples,the results show that the cross-sectional performance of the umbilical obtained by optimization algorithm is better and the solution efficiency is ***,the multi-layering strategy is effective and *** design method proposed in this paper can quickly obtain the optimal multi-layer cross-sectional layout,which replaces the manual design,and provides useful reference and guidance for the umbilical industry.

关键词： umbilical cross-sectional layout multi-layers GA-GLM optimization

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An unprecedented synthesis of axially chiral biaryls by rearrangement and aromatization of carbocations with central-to-axial conversion of chirality

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Science China Chemistry 2024年第9期67卷 2998-3003页

作者： qi Liu Xue-Dong Li Liang cheng Li Liu Beijing National Laboratory for Molecular Sciences(BNLMS) CAS Key Laboratory of Molecular Recognition and FunctionCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The central-to-axial chirality conversion represents a fascinating class of chemical processes consisting of the destruction of stereogenic centers and the simultaneous installation of axial chiral elements,which provides efficient methods for the preparation of axially chiral ***,developing catalytic asymmetric approaches for constructing these central chirality precursors and the efficient central-to-axial chirality conversion remains a challenge due to the requirement of aromatization or elimination *** this work,we have developed an unprecedented enantioselective intramolecular FriedelCrafts alkylation with unactivated-ketone carbonyls from which a chiral tertiary alcohol was generated with high efficiency and excellent *** addition,the central-to-axial chirality conversion strategy has been successfully applied to the synthesis of enantioenriched biaryls via a less-explored carbocation-initiated rearrangement and aromatization under the promotion of Lewis *** methodology provided a straightforward and sustainable access to a broad range of biaryl-2-carboxylic acid and in excellent yields(up to 92%)and excellent central-to-axial chirality conversion(up to 99%conversion percentage).This work could be a great model for developing new methods for synthesizing axially chiral biaryls and a general protocol for the rearrangement and aromatization of carbocations for further functionalization.

关键词： br?nsted acid catalysis desymmetrization phosphoric acid axially chiral biaryls central-to-axial conversion

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Strong Antiferromagnetic Exchange-Coupling Observed in Hydride-Bridged Dimeric Dysprosium(Ⅲ)Single-Molecule Magnet

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Chinese Journal of Chemistry 2024年第4期42卷 391-396页

作者： qian-cheng Luo Ke-Xin yu Peng-Bo Jin Ye-Ye Liu yuan-qi Zhai Yan-Zhen Zheng Frontier Institute of Science and Technology State Key Laboratory of Electrical Insulation and Power EquipmentXi'an Key Laboratory of Electronic Devices and Materials ChemistrySchool of Chemistry and School of PhysicsXi'an Jiaotong University99 Yanxiang RoadXi'anShaanxi710054 China

One dihydride-bridged dimeric Dy(Ⅲ)guanidinate complex,formulated as[{(Me_(3)Si)_(2)NC(NiPr)_(2)}_(2)Dy(μ-H)]_(2)(1Dy),was successfully isolated and the introduction of hydride bridges significantly reduces the intramolecular Dy(Ⅲ)…Dy(Ⅲ)distance to only 3.688(1)Å.To investigate the effect of such a short Dy(Ⅲ)…Dy(Ⅲ)distance on magnetism,we also prepared its dibromide-bridged analogue[{(Me_(3)Si)_(2)NC(NiPr)_(2)}_(2)Dy(μ-Br)]_(2)(2Dy),which has a much longer Dy(Ⅲ)…Dy(Ⅲ)distance of 4.605(4)Å.Surprisingly,2Dy demonstrates much larger effective energy barrier for magnetization reversal(U_(eff))and higher blocking temperature(T_(B)).The worse performance of 1Dy is attributed to the concerted effect of strong antiferromagnetic interactions between Dy(Ⅲ)ions(J_(total)=–2.683 cm^(–1))and the unparallel arrangement of magnetic principle axes of the Dy(Ⅲ)ions for 1Dy.

关键词： Single-molecule magnets Lanthanides Guanidinate ligand Hydride bridge Magnetic properties Ab initio calculations

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Experimental investigation on weak shock wave mitigation characteristics of flexible polyurethane foam and polyurea

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Defence Technology（防务技术） 2024年第1期31卷 179-191页

作者： Shiyu Jia cheng Wang Wenlong Xu Dong Ma Fangfang qi State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Institute for Advanced Technology Shandong UniversityJinan250061China

In recent years,explosion shock wave has been considered as a signature injury of the current military *** strong shock wave is lethal to the human body,weak shock wave can cause many more lasting *** investigate the protection ability and characteristics of flexible materials and structures under weak shock wave loading,the blast wave produced by TNT explosive is loaded on the polyurethane foam with the density of 200.0 kg/m3(F-200)and 400.0 kg/m3(F-400),polyurea with the density of 1100.0 kg/m^(3)(P-1100)and structures composed of the two materials,which are intended for individual *** results indicate that the shock wave is attenuated to weak pressure disturbance after interacting with the flexible materials which are not *** shock wave protective capability of single-layer materials is dependent on their thickness,density and microscopic *** overpressure,maximum pressure rise rate and impulse of transmitted wave decrease exponentially with increase in sample *** the same thickness,F-400 provides better protective capability than F-200 while P-1100 shows the best protective capability among the three *** this study,as the materials are not destroyed,F-200 with a thickness more than10.0 mm,F-400 with a thickness more than 4.0 mm,and P-1100 with a thickness more than 1.0 mm can attenuate the overpressure amplitude more than 90.0%.Further,multi-layer flexible composites are *** layer layouts of designed structures and layer thickness of the single-layer materials can affect the protective *** the research range,the structure in which polyurea is placed on the impact side shows the optimal shock wave protective performance,and the thicknesses of polyurea and polyurethane foam are 1.0 mm and 4.0 mm *** overpressure attenuation rate reached maximum value of 93.3%and impulse attenuation capacity of this structure are better than those of s

关键词： Free-field explosion Weak shock wave mitigation Polyurea Polyurethane foam Multi-layered composites

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Concentration-dependent effects of reductive pulmonary inhalants on ultrafine particle-induced oxidative stress:Insights for health risk assessment

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Environmental Science and Ecotechnology 2024年第3期19卷 118-124页

作者： Ya-qi yu Tong Zhu BIC-ESAT and SKL-ESPC College of Environmental Sciences and EngineeringPeking UniversityBeijing100871PR China School of Environmental Science and Engineering Qingdao UniversityQingdao266071PR China

The impact of reductive pulmonary inhalants on ultrafine particles(UFPs)-induced pulmonary oxidative stress remains a crucial consideration,yet the concentration-dependent effects of these inhalants have remained *** we synthesized composite UFPs simulating atmospheric UFPs,primarily composed of metals and *** subjected these UFPs to varying concentrations(0e7000 mM)of two reductive pulmonary inhalants,N-acetylcysteine and salbutamol,to assess their influence on oxidative potential,measured through the dithiothreitol assay(OP^(DTT)).Simultaneously,we analysed the soluble metal content of UFPs to uncover potential relationships between oxidative potential and metal *** results unveil a dual role played by these inhalants in shaping the OPDTT of composite ***,OP^(DTT) generally increased as inhalant concentrations rose from 0 to 300 ***,an intriguing reversal occurred when concentrations exceeded 500 mM,resulting in a decline in *** to untreated UFPs,these inhalants induced promotion and inhibition effects within concentration ranges of 100e500 and>1000 mM,*** no significant correlation emerged between OP^(DTT) and soluble metal content as inhalant concentrations ranged from 0 to 7000 mM,noteworthy positive correlations emerged at lower inhalant concentrations(e.g.,N-acetylcysteine at 0 e300 mM).These findings provide insights into the potential influence of reductive pulmonary inhalants on health risks associated with UFP exposure,further underscoring the need for continued research in this critical area.

关键词： Concentration-dependent effects Oxidative potential Reductive pulmonary inhalants Soluble metals Simulated atmospheric ultrafine particles

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Determination of the Pile Drivability Using Random Forest Optimized by Particle Swarm Optimization and Bayesian Optimizer

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Computer Modeling in Engineering & Sciences 2024年第10期141卷 871-892页

作者： Shengdong cheng Juncheng Gao Hongning qi State Key Laboratory of Eco-Hydraulics in Northwest Arid Region Xi’an University of TechnologyXi’an710048China School of Resources and Safety Engineering Central South UniversityChangsha410083China

Driven piles are used in many geological environments as a practical and convenient structural ***,the determination of the drivability of piles is actually of great importance in complex geotechnical *** methods of predicting pile drivability often rely on simplified physicalmodels or empirical formulas,whichmay lack accuracy or applicability in complex geological ***,this study presents a practical machine learning approach,namely a Random Forest(RF)optimized by Bayesian Optimization(BO)and Particle Swarm Optimization(PSO),which not only enhances prediction accuracy but also better adapts to varying geological environments to predict the drivability parameters of piles(i.e.,maximumcompressive stress,maximum tensile stress,and blow per foot).In addition,support vector regression,extreme gradient boosting,k nearest neighbor,and decision tree are also used and applied for comparison *** order to train and test these models,among the 4072 datasets collected with 17model inputs,3258 datasets were randomly selected for training,and the remaining 814 datasets were used for model ***,the results of these models were compared and evaluated using two performance indices,i.e.,the root mean square error(RMSE)and the coefficient of determination(R2).The results indicate that the optimized RF model achieved lower RMSE than other prediction models in predicting the three parameters,specifically 0.044,0.438,and 0.146;and higher R^(2) values than other implemented techniques,specifically 0.966,0.884,and *** addition,the sensitivity and uncertainty of the optimized RF model were analyzed using Sobol sensitivity analysis and Monte Carlo(MC)*** can be concluded that the optimized RF model could be used to predict the performance of the pile,and it may provide a useful reference for solving some problems under similar engineering conditions.

关键词： Random forest regression model pile drivability Bayesian optimization particle swarm optimization

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L-Type Calcium Channel Modulates Low-Intensity Pulsed Ultrasound-Induced Excitation in Cultured Hippocampal Neurons

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Neuroscience Bulletin 2024年第7期40卷 921-936页

作者： Wen-Yong Fan Yi-Ming Chen Yi-Fan Wang yu-qi Wang Jia-qi Hu Wen-Xu Tang Yi Feng qian cheng Lei Xue State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science Fudan UniversityShanghai 200433China Department of Physiology and Neurobiology School of Life SciencesFudan UniversityShanghai 200438China Institute of Acoustics School of Physics Science and EngineeringTongji UniversityShanghai 200092China Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of Ministry of Education Tongji UniversityShanghai 200070China Center for Rehabilitation Medicine Department of Pain ManagementZhejiang Provincial People's HospitalAffliated People's HospitalHangzhou Medical CollegeHangzhou 310014China Department of Critical Care Medicine Shanghai General HospitalShanghai Jiaotong University School of MedicineShanghai 200080China Shanghai Research Institute for Intelligent Autonomous Systems Tongji UniversityShanghai 201210China Research Institute of Intelligent Complex Systems Fudan UniversityShanghai 200433China

As a noninvasive technique,ultrasound stimulation is known to modulate neuronal activity both in vitro and in *** latest explanation of this phenomenon is that the acoustic wave can activate the ion channels and further impact the electrophysiological properties of targeted ***,the underlying mechanism of low-intensity pulsed ultrasound(LIPUS)-induced neuro-modulation effects is still ***,we characterize the excitatory effects of LIPUS on spontaneous activity and the intracellular Ca^(2+)homeostasis in cultured hippocampal *** whole-cell patch clamp recording,we found that 15 min of 1-MHz LIPUS boosts the frequency of both spontaneous action potentials and spontaneous excitatory synaptic currents(sEPSCs)and also increases the amplitude of sEPSCs in hippocampal *** phenomenon lasts for>10 min after LIPUS *** with Ca^(2+)imaging,we clarified that LIPUS increases the[Ca^(2+)]cyto level by facilitating L-type Ca^(2+)channels(LTCCs).In addition,due to the[Ca^(2+)]cyto elevation by LIPUS exposure,the Ca^(2+)-dependent CaMKII-CREB pathway can be activated within 30 min to further regulate the gene transcription and protein *** work suggests that LIPUS regulates neuronal activity in a Ca^(2+)-dependent manner via *** may also explain the multi-activation effects of LIPUS beyond *** stimulation potentiates spontaneous neuronal activity by increasing Ca^(2+)influx.

关键词： Low-intensity pulsed ultrasound Neuromodulation L-type calcium channel Hippocampal neuron

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Pyrimethamine upregulates BNIP3 to interfere SNARE-mediated autophagosome-lysosomal fusion in hepatocellular carcinoma

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Journal of Pharmaceutical Analysis 2024年第2期14卷 211-224页

作者： Jingjing Wang qi Su Kun Chen qing Wu Jiayan Ren Wenjuan Tang yu Hu Zeren Zhu cheng cheng Kaihui Tu Huaizhen He Yanmin Zhang School of Pharmacy Health Science CenterXi'an Jiaotong UniversityXi'an710061China

Hepatocellular carcinoma (HCC) is one of the most common tumor types and remains a major clinical challenge. Increasing evidence has revealed that mitophagy inhibitors can enhance the effect of chemotherapy on HCC. However, few mitophagy inhibitors have been approved for clinical use in humans. Pyrimethamine (Pyr) is used to treat infections caused by protozoan parasites. Recent studies have reported that Pyr may be beneficial in the treatment of various tumors. However, its mechanism of action is still not clearly defined. Here, we found that blocking mitophagy sensitized cells to Pyr-induced apoptosis. Mechanistically, Pyr potently induced the accumulation of autophagosomes by inhibiting autophagosome-lysosome fusion in human HCC cells. In vitro and in vivo studies revealed that Pyr blocked autophagosome-lysosome fusion by upregulating BNIP3 to inhibit synaptosomal-associated protein 29 (SNAP29)-vesicle-associated membrane protein 8 (VAMP8) interaction. Moreover, Pyr acted synergistically with sorafenib (Sora) to induce apoptosis and inhibit HCC proliferation in vitro and in vivo. Pyr enhances the sensitivity of HCC cells to Sora, a common chemotherapeutic, by inhibiting mitophagy. Thus, these results provide new insights into the mechanism of action of Pyr and imply that Pyr could potentially be further developed as a novel mitophagy inhibitor. Notably, Pyr and Sora combination therapy could be a promising treatment for malignant HCC.

关键词： Pyrimethamine BNIP3 SNARE Autophagosome-lysosome fusion Hepatocellular carcinoma Sorafenib

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Advances in neuroimaging studies of alcohol use disorder(AUD)

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Psychoradiology 2022年第4期2卷 146-155页

作者： Ji-yu Xie Rui-Hua Li Wei yuan Jiang Du Dong-Sheng Zhou yu-qi cheng Xue-Ming Xu Heng Liu Ti-Fei yuan School of Mental Health Wenzhou Medical UniversityWenzho 325000ZhejianguChina Shandong Mental Health Center Shandong UniversityJinan 250014ShandongChina Shanghai Mental Health Center Shanghai Jiaotong University School of MedicineShanghai 200030China Department of Psychiatry Ningbo Kangning HospitalNingbo 315000ZhejiangChina Department of Psychiatry First Affiliated Hospital of Kunming Medical UniversityKunming 650000YunnanChina Department of Psychiatry Taizhou Second People’s HospitalTaizhou 318000ZhejiangChina Department of Radiology the Affiliated Hospital of Zunyi Medical UniversityMedical Imaging Center of Guizhou ProvinceZunyi 563000GuizhouChina

Alcohol use disorder(AUD)is a worldwide problem and themost common substance use *** alcohol consumptionmay have negative effects on the body,the mind,the family,and even *** the progress of current neuroimaging methods,an increasing number of imaging techniques are being used to objectively detect brain impairment induced by alcoholism and serve a vital role in the diagnosis,prognosis,and treatment assessment of *** article organizes and analyzes the research on alcohol dependence concerning the main noninvasive neuroimaging methods,structural magnetic resonance imaging,functional magnetic resonance imaging,and electroencephalography,as well as the most common noninvasive brain stimulation-transcranial magnetic stimulation,and intersperses the article with joint intra-and intergroup studies,providing an outlook on future research directions.

关键词： alcohol use disorder structural magnetic resonance imaging functionalmagnetic resonance imaging electroencephalography transcranial magnetic stimulation prefrontal cortex

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Understanding the spatial interaction of ultrasounds based on three-dimensional dual-frequency ultrasonic field numerical simulation

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China Foundry 2024年第1期21卷 29-43页

作者： Zhao-yang Yin qi-chi Le Yan-chao Jiang Da-zhi Zhao qi-yu Liao qi Zou Key Lab of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China

A transient 3D model was established to investigate the effect of spatial interaction of ultrasounds on the dual-frequency ultrasonic field in magnesium alloy *** effects of insertion depth and tip shape of the ultrasonic rods,input pressures and their ratio on the acoustic field distribution were discussed in ***,the spacing,angle,and insertion depth of two ultrasonic rods significantly affect the interaction between distinct *** a result,various acoustic pressure distributions and cavitation regions are *** spherical rods mitigate the longitudinal and transversal attenuation of acoustic pressure and expand the cavitation volume by 53.7%and 31.7%,respectively,compared to the plate and conical *** the input pressure will enlarge the cavitation region but has no effect on the acoustic pressure distribution *** acoustic pressure ratio significantly affects the pressure distribution and the cavitation region,and the best cavitation effect is obtained at the ratio of 2:1(P15:P20).

关键词： dual-frequency ultrasonic numerical model acoustic pressure spatial interaction magnesium alloy

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