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Significant contribution of carbonyls to atmospheric oxidation capacity(AOC)during the winter haze pollution over North China Plain

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Journal of Environmental Sciences 2024年第5期139卷 377-388页

作者： Xue Yang Gen Zhang guang pan Guolan Fan Houyong Zhang Xuan Ge Mingyue Du School of Municipal and Environmental Engineering Shandong Jianzhu UniversityJi’nan 250101China State Key Laboratory of Severe Weather&Key Laboratory of Atmospheric Chemistry of China Meteorological Administration Chinese Academy of Meteorological SciencesBeijing 100081China Shandong Jinan Ecological Environment Monitoring Center Ji’nan 250101China

Atmospheric carbonyl compounds play significant roles in the cycling of radicals and have exhibited surprisingly high levels in winter that were well correlated to particulate matter,for which the reason have not been clearly elucidated.Here we measured carbonyl compounds and other trace gasses together with PM_(2.5)over urban Jinan in North China Plain during the winter.Markedly higher carbonyl concentrations(average:14.63±4.21 ppbv)were found during wintertime haze pollution,about one to three-times relative to those on nonhaze days,with slight difference in chemical composition except formaldehyde(HCHO).HCHO(3.68 ppbv),acetone(3.17 ppbv),and acetaldehyde(CH_3CHO)(2.83 ppbv)were the three most abundant species,accounting for~75% of the total carbonylson both haze and non-haze days.Results from observational-based model(OBM)with atmospheric oxidation capacity(AOC)indicated that AOC significantly increased with the increasing carbonyls during the winter haze events.Carbonyl photolysis have supplied key oxidants such as RO_(2) and HO_(2),and thereby enhancing the formation of fine particles and secondary organic aerosols,elucidating the observed haze-carbonyls inter-correlation.Diurnal variation with carbonyls exhibiting peak values at early-noon and night highlighted the combined contribution of both secondary formation and primary diesel-fuel sources.1-butene was further confirmed to be the major precursor for HCHO.This study confirms the great contribution of carbonyls to AOC,and also suggests that reducing the emissions of carbonyls would be an effective way to mitigate haze pollution in urban area of the NCP region.

关键词： Carbonyls Haze Observation-based model Source apportionment Atmospheric oxidation capacity

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Development and validation of a nomogram to predict allograft survival after pediatric liver transplantation

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World Journal of Pediatrics 2024年第3期20卷 239-249页

作者： guang-Xiang Gu Shu-Ting pan Yi-Chen Fan Chen Chen Qiang Xia Department of Liver Surgery Renji HospitalShanghai Jiaotong University School of MedicineNo.160 Pujian RoadPudong New DistrictShanghai 200128China Department of Liver Transplantation Sun Yet-Sen Memorial HospitalSun Yat-Sen UniversityNo.107 Yanjiang West RoadGuangzhou 510080China Clinical Center for Investigation Renji HospitalShanghai Jiaotong University School of MedicineShanghaiChina Department of Anesthesiology Renji HospitalShanghai Jiaotong University School of MedicineShanghaiChina

Background Liver transplantation is the main treatment for cholestatic liver disease and some metabolic liver diseases in children.However,no accurate prediction model to determine the survival probability of grafts prior to surgery exists.This study aimed to develop an effective prognostic model for allograft survival after pediatric liver transplantation.Methods This retrospective cohort study included 2032 patients who underwent pediatric liver transplantation between January 1,2006,and January 1,2020.A nomogram was developed using Cox regression and validated based on bootstrap sampling.Predictive and discriminatory accuracies were determined using the concordance index and visualized using calibration curves;net benefits were calculated for model comparison.An online Shiny application was developed for easy access to the model.Results Multivariable analysis demonstrated that preoperative diagnosis,recipient age,body weight,graft type,preoperative total bilirubin,interleukin-1β,portal venous blood flow direction,spleen thickness,and the presence of heart disease and cholangitis were independent factors for survival,all of which were selected in the nomogram.Calibration of the nomogram indicated that the 1-,3-,and 5-year predicted survival rates agreed with the actual survival rate.The concordance indices for graft survival at 1,3,and 5 years were 0.776,0.757,and 0.753,respectively,which were significantly higher than those of the Pediatric End-Stage Liver Disease and Child-Pugh scoring systems.The allograft dysfunction risk of a recipient could be easily predicted using the following URL:https://aspelt.***.io/ASPELT/l Conclusion The allograft survival after pediatric liver transplantation(ASPELT)score model can effectively predict the graft survival rate after liver transplantation in children,providing a simple and convenient evaluation method for clinicians and patients.

关键词： Allograft survival Nomogram Pediatric liver transplantation

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Shear band evolution and acoustic emission characteristics of sandstone containing non-persistent flaws

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 497-513页

作者： Shuting Miao Peng-zhi pan Chuanqing Zhang Lei Huo State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China CASIC Research Institute of Intelligent Decision Engineering Wuhan430040China

Direct shear tests were conducted on sandstone specimens under different constant normal stresses to study the coalescence of cracks between non-persistent flaws and the shear sliding characteristics of the shear-formed fault.Digital image correlation and acoustic emission(AE)techniques were used to monitor the evolution of shear bands at the rock bridge area and microcracking behaviors.The experimental results revealed that the shear stresses corresponding to the peak and sub-peak in the stressdisplacement curve are significantly affected by the normal stress.Strain localization bands emerged at both the tip of joints and the rock bridge,and their extension and interaction near the peak stress caused a surge in the AE hit rate and a significant decrease in the AE b value.Short and curvilinear strain bands were detected at low normal stress,while high normal stress generally led to more microcracking events and longer coplanar cracks at the rock bridge area.Furthermore,an increase in normal stress resulted in a higher AE count rate and more energetic AE events during friction sliding along the shearformed fault.It was observed that the elastic energy released during the crack coalescence at the prepeak stage was much greater than that released during friction sliding at the post-peak stage.More than 75%of AE events were located in the low-frequency band(0e100 kHz),and this proportion continued to rise with increasing normal stress.Moreover,more AE events of low AF value and high RA value were observed in specimens subjected to high normal stress,indicating that greater normal stress led to more microcracks of shear nature.

关键词： Shear band evolution Acoustic emission(AE) Crack coalescence Normal stress Shear sliding

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Effect of Active–Passive Deformation on the Thrust by the Pectoral Fins of Bionic Manta Robot

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Journal of Bionic Engineering 2024年第2期21卷 718-728页

作者： Yang Lu Shaomin Meng Cheng Xing Yiwei Hao Yonghui Cao guang pan Yong Cao School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an710072China Unmanned Vehicle Innovation Center Ningbo Institute of NPUNingbo315103China State Key Lab of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou310027China Zhejiang Key Laboratory of Advanced Manufacturing Technology School of Mechanical EngineeringZhejiang UniversityHangzhou310027China

Bionic manta underwater vehicles will play an essential role in future oceans and can perform tasks,such as long-duration reconnaissance and exploration,due to their efficient propulsion.The manta wings’deformation is evident during the swimming process.To improve the propulsion performance of the unmanned submersible,the study of the deformation into the bionic pectoral fin is necessary.In this research,we designed and fabricated a flexible bionic pectoral fin,which is based on the Fin Ray®effect with active and passive deformation(APD)capability.The APD fin was actively controlled by two servo motors and could be passively deformed to variable degrees.The APD fin was moved at 0.5 Hz beat frequency,and the propulsive performance was experimentally verified of the bionic pectoral fins equipped with different extents of deformation.These results showed that the pectoral fin with active–passive deformed capabilities could achieve similar natural biological deformation in the wingspan direction.The average thrust(T)under the optimal wingspan deformation is 61.5%higher than the traditional passive deformed pectoral fins.The obtained results shed light on the design and optimization of the bionic pectoral fins to improve the propulsive performance of unmanned underwater vehicles(UUV).

关键词： Manta ray Bionic pectoral fin Fin Ray®effect Active-passive deformation(APD)

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What is the Role of Gravity, Turbulence and Magnetic Fields in High-mass Star Formation Clouds?

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Research in Astronomy and Astrophysics 2024年第6期24卷 23-29页

作者： An-Xu Luo Hong-Li Liu guang-Xing Li Sirong pan Dong-Ting Yang School of Physics and Astronomy Yunnan University South-Western Institute for Astronomy Research Yunnan University

To explore the potential role of gravity,turbulence and magnetic fields in high-mass star formation in molecular clouds,this study revisits the velocity dispersion–size （σ–L） and density–size （ρ–L） scalings and the associated turbulent energy spectrum using an extensive data sample.The sample includes various hierarchical density structures in high-mass star formation clouds,across scales of 0.01–100 pc.We observe σ∝L0.26and ρ∝L-1.54scalings,converging toward a virial equilibrium state.A nearly flat virial parameter–mass (αvir-M) distribution is seen across all density scales,with αvirvalues centered around unity,suggesting a global equilibrium maintained by the interplay between gravity and turbulence across multiple scales.Our turbulent energy spectrum (E（k）)analysis,based on theσ–L andρ–L scalings,yields a characteristic E（k）∝k-1.52.These findings indicate the potential significance of gravity,turbulence,and possibly magnetic fields in regulating dynamics of molecular clouds and high-mass star formation therein.

关键词： ISM: clouds stars: formation stars: kinematics and dynamics

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Multi-scale data joint inversion of minerals and porosity in altered igneous reservoirs—A case study in the South China Sea

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Petroleum Science 2024年第1期21卷 206-220页

作者： Xin-Ru Wang Bao-zhi pan Yu-Hang Guo Qing-Hui Wang Yao Guan College of Geo-exploration Science and Technology Jilin UniversityChangchun130046JilinChina Research Institute CNOOC Ltd.-ShenzhenShenzhen518000GuangdongChina

There are abundant igneous gas reservoirs in the South China Sea with significant value of research,and lithology classification,mineral analysis and porosity inversion are important links in reservoir evaluation.However,affected by the diverse lithology,complicated mineral and widespread alteration,conventional logging lithology classification and mineral inversion become considerably difficult.At the same time,owing to the limitation of the wireline log response equation,the quantity and accuracy of minerals can hardly meet the exploration requirements of igneous formations.To overcome those issues,this study takes the South China Sea as an example,and combines multi-scale data such as micro rock slices,petrophysical experiments,wireline log and element cutting log to establish a set of joint inversion methods for minerals and porosity of altered igneous rocks.Specifically,we define the lithology and mineral characteristics through core slices and mineral data,and establish an igneous multi-mineral volumetric model.Then we determine element cutting log correction method based on core element data,and combine wireline log and corrected element cutting log to perform the lithology classification and joint inversion of minerals and porosity.However,it is always difficult to determine the elemental eigenvalues of different minerals in inversion.This paper uses multiple linear regression methods to solve this problem.Finally,an integrated inversion technique for altered igneous formations was developed.The results show that the corrected element cutting log are in good agreement with the core element data,and the mineral and porosity results obtained from the joint inversion based on the wireline log and corrected element cutting log are also in good agreement with the core data from X-ray diffraction.The results demonstrate that the inversion technique is applicable and this study provides a new direction for the mineral inversion research of altered igneous formations.

关键词： Joint inversion Altered igneous rock Element correction method Lithology identification Multi mineral volume model

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Bioinspired Closed-loop CPG-based Control of a Robotic Manta for Autonomous Swimming

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Journal of Bionic Engineering 2024年第1期21卷 177-191页

作者： Yiwei Hao Yonghui Cao Yingzhuo Cao Xiong Mo Qiaogao Huang Lei Gong guang pan Yong Cao School of Marine Science and Technology Northwestern Polytechnical UniversityXi'an 710072China Unmanned Vehicle Innovation Center Ningbo Institute of NPUNingbo 315103China Key Laboratory of Unmanned Underwater Vehicle Technology of Ministry of Industry and Information Technology Xi'an 710072China

Fish in nature exhibit a variety of swimming modes such as forward swimming,backward swimming,turning,pitching,etc.,enabling them to swim in complex scenes such as coral reefs.It is still difficult for a robotic fish to swim autonomously in a confined area as a real fish.Here,we develop an untethered robotic manta as an experimental platform,which consists of two flexible pectoral fins and a tail fin,with three infrared sensors installed on the front,left,and right sides of the head to sense the surrounding obstacles.To generate multiple swimming modes of the robotic manta and online switching of different modes,we design a closed-loop Central Pattern Generator(CPG)controller based on distance information and use a combination of phase difference and amplitude of the CPG model to achieve stable and rapid adjustment of yaw angle.To verify the autonomous swimming ability of the robotic manta in complex scenes,we design an experimental scenario with a concave obstacle.The experimental results show that the robotic manta can achieve forward swimming,backward swimming,in situ turning within the concave obstacle,and finally exit from the area safely while relying on the perception of external obstacles,which can provide insight into the autonomous exploration of complex scenes by the biomimetic robotic fish.Finally,the swimming ability of the robotic manta is verified by field tests.

关键词： Biomimetic robotic manta Central Pattern Generator Closed-loop control Backward swimming

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Endovascular treatment of direct carotid cavernous fistula resulting from rupture of intracavernous carotid aneurysm: A case report

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World Journal of Clinical Cases 2024年第11期12卷 1940-1946页

作者： guang Ouyang Kai-Li Zheng Kuan Luo Mu Qiao Yuan Zhu De-Rui pan Department of Neurosurgery Puren Hospital Affiliated to Wuhan University of Science and TechnologyWuhan 430081Hubei ProvinceChina Department of Neurosurgery The Third Hospital of WuhanWuhan 430081Hubei ProvinceChina

BACKGROUND Direct carotid cavernous fistulas(CCFs)are typically the result of a severe traumatic brain injury.High-flow arteriovenous shunts secondary to rupture of an intracavernous aneurysm,resulting in direct CCFs,are rare.The use of a pipeline embolization device in conjunction with coils and Onyx glue for treatment of direct high-flow CCF resulting from ruptured cavernous carotid artery aneurysm in a clinical setting is not well documented.CASE SUMMARY A 58-year-old woman presented to our department with symptoms of blepharoptosis and intracranial bruits for 1 wk.During physical examination,there was right eye exophthalmos and ocular motor palsy.The rest of the neurological examination was clear.Notably,the patient had no history of head injury.The patient was treated with a pipeline embolization device in the ipsilateral internal carotid artery across the fistula.Coils and Onyx were placed through the femoral venous route,followed by placement of the pipeline embolization device with assistance from a balloon-coiling technique.No intraoperative or perioperative complications occurred.Preoperative symptoms of bulbar hyperemia and bruits subsided immediately after the operation.CONCLUSION Pipeline embolization device in conjunction with coiling and Onyx may be a safe and effective approach for direct CCFs.

关键词： Intravascular therapy Carotid cavernous fistulas Intracavernous carotid aneurysms Case report

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Role of savolitinib in advanced gastric adenocarcinoma with meningeal carcinomatosis and cerebellar metastasis:A case report

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World Journal of Clinical Cases 2024年第15期12卷 2636-2641页

作者： zhi-Yun Weng Wen-Ye Huang Bin-Kan Shi Jian-Jia pan Department of Hematology The Affiliated Yueqing Hospital of Wenzhou Medical UniversityYueqing 325600Zhejiang ProvinceChina

BACKGROUND Brain metastases(BM)are very rare in gastric adenocarcinoma(GaC),and patients with BMs have a higher mortality rate due to stronger tumor aggressiveness.However,its pathogenesis remains unclear.Genetic testing revealed cellular-mesenchymal epithelial transition factor receptor(MET)amplification.Therefore,treatment with savolitinib,a small molecule inhibitor of c-Met,was selected.CASE SUMMARY A 66-year-old woman was diagnosed with advanced GaC 6 months prior to presentation due to back pain.Cerebellar and meningeal metastases were observed during candonilimab combined with oxaliplatin and capecitabine therapy.The patient experienced frequent generalized seizures and persistent drowsiness in the emergency department.Genetic testing of cerebrospinal fluid and peripheral blood revealed increased MET amplification.After discussing treatment options with the patient,savolitinib tablets were administered.After a month of treatment,the intracranial lesions shrank considerably.CONCLUSION BM is very rare in advanced GaC,especially in meningeal cancer,that is characterized by rapid disease deterioration.There are very few effective treatment options available;however,technological breakthroughs in genomics have provided a basis for personalized treatment.Furthermore,MET amplification may be a key driver of BM in gastric cancer;however,this conclusion requires further investigation.

关键词： Cellular-mesenchymal epithelial transition factor receptor Savolitinib Meningeal carcinomatosis Gastric adenocarcinoma Case report

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Multi-physical fields distribution in billet during helical electromagnetic stirring:A numerical simulation research

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China Foundry 2024年第1期21卷 51-59页

作者： Dong pan Qing-tao Guo Kai-lun Zhang Fu-zhi Yu Yu-ying Li Yu-bao Xiao State Key Laboratory of Metal Materials for Marine Equipment and Application Anshan 114009LiaoningChina Ansteel Beijing Research Institute Co. Ltd.Beijing 102200China

Electromagnetic stirring is one of the widely applied techniques to modify the quality of casting billets.Different from conventional rotate stirring,the helical stirring is more professional in assisting multi-dimensional flow of molten metal and eliminating solidification defects.In this study,the single-winding helical stirring(SWHS)was introduced,offering advantages such as smaller volume and lower electromagnetic shielding compared to traditional helical stirring methods.Following a comprehensive numerical simulation,the stirring parameters of SWHS were adjusted to yoke inclination angle of 43°and frequency of 12 Hz.The higher electromagnetic force and flow velocity in drawing direction,as well as the lower temperature gradient induced by the SWHS,are positive factors for homogeneous solidification of billet.The experimental results on Al-8%Si alloy and 0.4%C-1.1%Mn steel demonstrate that compared to rotate stirring,the SWHS process can induce better billet quality and is more effective in accelerating the equiaxed expansion and reducing element segregation.The SWHS process can enhance the equiaxed ratio of the billet by 58.3%and reduce segregation degree of carbon element by 10.97%.Consequently,SWHS holds great promise as a potential approach for improving the quality of continuous casting billets.

关键词： billet electromagnetic stirring helical solidification element segregation numerical simulation

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