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Young patient with a giant gastric bronchogenic cyst:A case report and review of literature

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World Journal of Clinical Cases 2024年第13期12卷 2254-2262页

作者： xu-Ren Lu xu-guang Jiao Qi-Hang Sun Bo-Wen Li Qing-Shun Zhu guang-xu Zhu Jian-Jun Qu School of Clinical Medicine Shandong Second Medical UniversityWeifang 261000Shandong ProvinceChina Department of Gastrointestinal Surgery Medical Center The First Affiliated HospitalShandong Second Medical UniversityWeifang 261000Shandong ProvinceChina

BACKGROUND Gastric bronchogenic cysts(BCs)are extremely rare cystic masses caused by abnormal development of the respiratory system during the embryonic period.Gastric bronchial cysts are rare lesions that were first reported in 1956;as of 2023,only 33 cases are available in the PubMed online database.BCs usually have no clinical symptoms in the early stage,and imaging findings also lack specificity.Therefore,they are difficult to diagnose before histopathological examination.CASE SUMMARY A 34-year-old woman with respiratory distress presented at our hospital.Endoscopic ultrasound revealed an anechoic mass between the spleen,left kidney and gastric fundus,with hyperechogenic and soft elastography textures and with a size of approximately 6.5 cm×4.0 cm.Furthermore,a computed tomography scan demonstrated high density between the posterior stomach and the spleen and the left kidney,with uniform internal density and a small amount of calcification.The maximum cross section was approximately 10.1 cm×6.1 cm,and the possibility of a cyst was high.Because the imaging findings did not suggest a malignancy and because the patient required complete resection,she underwent laparotomy surgery.Intraoperatively,this cystic lesion was found to be located in the posterior wall of the large curvature of the fundus and was approximately 8 cm×6 cm in size.Finally,the pathologists verified that the cyst in the fundus was a gastric BC.The patient recovered well,her symptoms of chest tightness disappeared,and the abdominal drain was removed on postoperative day 6,after which she was discharged on day 7 for 6 months of follow-up.She had no tumor recurrence or postoperative complications during the follow-up.CONCLUSION This is a valuable report as it describes an extremely rare case of gastric BC.Moreover,this was a very young patient with a large BC in the stomach.

关键词： Bronchogenic cyst Stomach Endoscopic ultrasound-guided fine needle aspiration Endosonography Case report

Electromagnetic fields in ultra-peripheral relativistic heavy-ion collisions

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Nuclear Science and Techniques 2024年第2期35卷 103-109页

作者： Jie Zhao Jin-Hui Chen xu-guang Huang Yu-Gang Ma Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China Shanghai Research Center for Theoretical Nuclear Physics NSFC and Fudan UniversityShanghai 200438China Physics Department and Center for Particle Physics and Field Theory Fudan UniversityShanghai 200438China

Ultra-peripheral heavy-ion collisions(UPCs)offer unique opportunities to study processes under strong electromagnetic fields.In these collisions,highly charged fast-moving ions carry strong electromagnetic fields that can be effectively treated as photon fluxes.The exchange of photons can induce photonuclear and two-photon interactions and excite ions.This excitation of the ions results in Coulomb dissociation with the emission of photons,neutrons,and other particles.Additionally,the electromagnetic fields generated by the ions can be sufficiently strong to enforce mutual interactions between the two colliding ions.Consequently,the two colliding ions experience an electromagnetic force that pushes them in opposite directions,causing a back-to-back correlation in the emitted neutrons.Using a Monte Carlo simulation,we qualitatively demonstrate that the above electromagnetic effect is large enough to be observed in UPCs,which would provide a clear means to study strong electromagnetic fields and their effects.

关键词： Electromagnetic fields Neutrons Ultra-peripheral relativistic heavy-ion collisions(UPC)

维普期刊数据库

Spatiotemporal dynamics of the social structure of Indo-Pacific humpback dolphins(Sousa chinensis)in Xiamen waters from 2007 to 2019

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Zoological Research 2024年第2期45卷 439-450页

作者： Yi Lu Xin-Rong xu Bing-Yao Chen Thomas A Jefferson Holly Fearnbach guang Yang Jiangsu Key Laboratory for Biodiversity and Biotechnology College of Life SciencesNanjing Normal UniversityNanjingJiangsu 210023China Clymene Enterprises LakesideCalifornia 92040USA Marine Mammal Research SR3SeaLife ResponseRehabilitation and ResearchWA 98275USA Southern Marine Science and Engineering guangdong Laboratory(guangzhou) No.1119Haibin RoadNansha DistrictGuangzhouGuangdong 511458China

As highly social animals,Indo-Pacific humpback dolphins(Sousa chinensis)exhibit community differentiation.Nevertheless,our understanding of the external and internal factors influencing these dynamics,as well as their spatiotemporal variations,is still limited.In the present study,variations in the social structure of an endangered Indo-Pacific humpback dolphin population in Xiamen Bay,China,were monitored over two distinct periods(2007–2010 and 2017–2019)to analyze the effects of habitat utilization and the composition of individuals within the population.In both periods,the population demonstrated a strikingly similar pattern of social differentiation,characterized by the division of individuals into two main clusters and one small cluster.Spatially,the two primary clusters occupied the eastern and western waters,respectively,although the core distribution area of the eastern cluster shifted further eastward between the two periods.Despite this distribution shift,the temporal stability of the social structure and inter-associations within the eastern cluster remained unaffected.A subset of 16individuals observed in both periods,comprising 51.6%and 43.2%of the population in each respective period,emerged as a foundational element of the social structure and may be responsible for sustaining social structure stability,especially during the 2007–2010 period.These observations suggest that the composition of dominant individuals,an internal factor,had a more substantial influence on the formation of the social network than changes in habitat use,an external factor.Consequently,the study proposes distinct conservation measures tailored to each of the two main clusters.

关键词： Social differentiation Social structure Sousa chinensis Dynamics Conservation

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Variable projection algorithms with sparse constraint for separable nonlinear models

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Control Theory and Technology 2024年第1期22卷 135-146页

作者： Hui-Lang xu guang-Yong Chen Si-Qing Cheng Min Gan Jing Chen College of Computer and Data Science Fuzhou UniversityFuzhou350116FujianChina Fujian Key Laboratory of Network Computing and Intelligent Information Processing Fuzhou UniversityFuzhou350116FujianChina Key Laboratory of Intelligent Metro of Universities in Fujian Fuzhou UniversityFuzhou350116FujianChina Engineering Research Center of Big Data Intelligence Ministry of EducationFuzhou UniversityFuzhou350116FujianChina School of Science Jiangnan UniversityWuxi214122JiangsuChina

Separable nonlinear models are widely used in various fields such as time series analysis, system modeling, and machine learning, due to their flexible structures and ability to capture nonlinear behavior of data. However, identifying the parameters of these models is challenging, especially when sparse models with better interpretability are desired by practitioners. Previous theoretical and practical studies have shown that variable projection (VP) is an efficient method for identifying separable nonlinear models, but these are based on \(L_2\) penalty of model parameters, which cannot be directly extended to deal with sparse constraint. Based on the exploration of the structural characteristics of separable models, this paper proposes gradient-based and trust-region-based variable projection algorithms, which mainly solve two key problems: how to eliminate linear parameters under sparse constraint;and how to deal with the coupling relationship between linear and nonlinear parameters in the model. Finally, numerical experiments on synthetic data and real time series data are conducted to verify the effectiveness of the proposed algorithms.

关键词： Variable projection(VP) Non-smooth constraint Separable nonlinear models

Modulated noble metal/2D MOF heterostructures for improved hydrogen storage of MgH2

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Rare Metals 2024年第4期43卷 1672-1685页

作者： Zeng-Yi Li Li-Xian Sun Fen xu Yu-Mei Luo Yong-Peng Xia Sheng Wei Chen-Chen Zhang ri-guang Cheng Chao-Feng Ye Meng-Yuan Liu Ju-Lan Zeng Zhong Cao Hong-Ge Pan School of Material Science and Engineering Guilin University of Electronic Technology School of Chemistry and Chemical Engineering Changsha University of Science and Technology Institute of Science and Technology for New Energy Xi'an Technological University

The conjugation of external species with twodimensional（2D） materials has broad application prospects.In this study,we have explored the potential of noble metal/2D MOF heterostructures in hydrogen storage.Specifically,the MgH2-Ni-MOF@Pd system has shown remarkable hydrogen desorption/sorption performances,starting to liberate hydrogen at 181 0C,which is 230 0C lower than that of pristine MgH2.Under the catalytic effect of Ni-MOF@Pd,the dehydrogenation apparent activation energy of MgH2 is noticeably decreased from（133.5 ± 17.5） to（34.58 ± 1.87） kJ·mol-1,and the hydrogenation apparent activation energy is reduced from（70.41 ± 7.43） to（25.78 ± 4.64） kJ·mol-1,which is lowered by 63.4%.The fully-dehydrogenated MgH2-NiMOF@Pd composite rapidly uptakes hydrogen,with 2.62wt% at 100℃ and 6.06 wt% at 150℃ within 300 s,respectively.The mechanism analysis of MgH2 catalyzed by Ni-MOF@Pd has revealed that the transformation of Mg2Ni and Mg2NiH4could act as a "hydrogen pump",providing numerous channels for fast diffusion and transport of hydrogen atoms.Moreover,in the dehydrogenation process,the element Pd reacts with MgH2to form the MgPd alloy phase,which makes MgH2take precedence to decompose through the Mg-Pd alloy rather than self-decomposition,further reducing thermal stability and improving de/hydrogenation kinetics.The synergistic effect of Mg-Pd,Mg2Ni,and the special ultra-thin 2D sheet structure of the additive is the main reason for the good hydrogen storage property of MgH2-Ni-MOF@Pd.Our findings provide inspiration for designing efficient multifunctional additives with unique morphologies to optimize the hydrogen desorption/sorption behaviors of hydrogen storage materials.

关键词： Hydrogen storage Magnesium hydride 2D metal-organic framework nanosheets Ni/Pd Synergistic catalysis

Non-contact and full-field online monitoring of curing temperature during the in-situ heating process based on deep learning

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Advances in Manufacturing 2024年第1期12卷 167-176页

作者： Qiang-Qiang Liu Shu-Ting Liu Ying-guang Li xu Liu Xiao-Zhong Hao College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing210016People’s Republic of China School of Mechanical and Power Engineering Nanjing Tech UniversityNanjing211816People’s Republic of China

Online monitoring of the curing temperature field is essential to improving the quality and efficiency of the manufacturing process of composite parts.Traditional embedded sensor-based technologies have difficulty monitoring the full temperature field or have to introduce heterogeneous items that could have an undesired impact on the part.In this paper,a non-contact,full-field monitoring method based on deep learning that predicts the internal temperature field of composite parts in real time using surface temperature measurements of auxiliary materials is proposed.Using the proposed method,an average temperature monitoring accuracy of 97%is achieved in various heating patterns.In addition,this method also demonstrates satisfying feasibility when a stronger thermal barrier covers the part.This method was experimentally validated during the self-resistance electric heating process,in which the monitoring accuracy reached 93.1%.This method can potentially be applied to automated manufacturing and process control in the composites industry.

关键词： Online monitoring Curing temperature field Deep learning(DL) In-situ heating

Atomic-scale mechanism of effect of co-separation of elements at interface of ferrite and austenite on Cr-depleted zone of duplex stainless steel

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Journal of Iron and Steel Research(International) 2024年第3期31卷 710-718页

作者： Yan-hui Hou Ze-kun xu Shi-long Zhou guang-qiang Li The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081HubeiChina

Three-dimensional atom-probe tomography and first-principles calculation combined with density functional theory were used to study the effect of the co-segregation of different elements formed during the solidification process of S32205 duplex stainless steel on the Cr-depleted zone at the interface between ferrite and austenite.It was found that the co-segregation of different elements formed during the solidification process of duplex stainless steel can also form Cr-depleted zone at the interface between ferrite and austenite.Moreover,Mo,Si,B,C and P atoms promote co-segregation with Cr atoms,which promotes the formation of Cr-depleted zone at the interface between ferrite and austenite in duplex stainless steel.Mo and Si strongly promote the segregation of Cr at the interface between ferrite and austenite,thereby promoting the formation of Cr-depleted zone.B,C and P elements also promote the segregation of Cr element at the interface between ferrite and austenite and the formation of Cr-depleted zone,but their effect is weaker than that of Mo and Si elements.These conclusions provide a new theoretical basis for improving the intergranular corrosion performance of duplex stainless steel.

关键词： Duplex stainless steel Cr-depleted zone Intergranular corrosion Co-segregation First-principles calculation

Research on shell-side heat and mass transfer with multi-component in LNG spiral-wound heat exchanger under sloshing conditions

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Petroleum Science 2024年第2期21卷 1333-1345页

作者： xue-Ping Du guang-Lei Yu Ya-Cheng xu Zhi-Jie Chen Nai-Liang Li Huan-guang Wang School of Low-carbon Energy and Power Engineering China University of Mining and TechnologyXuzhou221116JiangsuChina Key Laboratory of Thermo-Fluid Science and Engineering MOEXi©an Jiaotong UniversityXi'an710049ShaanxiChina Xi©an Aerospace Propulsion Test Technology Institute Xi©an710100ShaanxiChina

The spiral-wound heat exchanger(SWHE) is the primary low-temperature heat exchanger for large-scale LNG plants due to its high-pressure resistance, compact structure, and high heat exchange efficiency. This paper studied the shell-side heat and mass transfer characteristics of vapor-liquid two-phase mixed refrigerants in an SWHE by combining a multi-component model in FLUENT software with a customized multicomponent mass transfer model. Besides, the mathematical model under the sloshing condition was obtained through mathematical derivation, and the corresponding UDF code was loaded into FLUENT as the momentum source term. The results under the sloshing conditions were compared with the relevant parameters under the steady-state condition. The shell-side heat and mass transfer characteristics of the SWHE were investigated by adjusting the component ratio and other working conditions. It was found that the sloshing conditions enhance the heat transfer performance and sometimes have insignificant effects. The sloshing condition is beneficial to reduce the flow resistance. The comprehensive performance of multi-component refrigerants has been improved and the improvement is more significant under sloshing conditions, considering both the heat transfer and pressure drop.These results will provide theoretical support for the research and design of multi-component heat and mass transfer enhancement of LNG SWHE under ocean sloshing conditions.

关键词： Spiral-wound heat exchanger Sloshing conditions Two-phase flow Multi-component Heat and mass transfer

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Static recrystallization behaviors and mechanisms of 7Mo super-austenitic stainless steel with undissolved sigma precipitates during double-stage hot deformation

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Journal of Iron and Steel Research(International) 2024年第2期31卷 475-487页

作者： Shi-guang xu Jin-shan He Run-ze Zhang Fu-cheng Zhang Xi-tao Wang Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing100083China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao066004HebeiChina Shandong Provincial Key Laboratory for High Strength Lightweight Metallic Materials Advanced Materials InstituteQilu University of Technology(Shandong Academy of Science)Jinan250353ShandongChina

Static recrystallization(SRX)behaviors and corresponding recrystallization mechanisms of 7Mo super-austenitic stainless steel were studied under different deformation conditions.The order of influence of deformation parameters on static recrystallization behaviors,from high to low,is followed by temperature,first-stage strain and strain rate.Meanwhile,the effect of holding time on static recrystallization behaviors is significantly controlled by temperature.In addition,with the increase in temperature from 1000 to 1200°C,the static recrystallization mechanism evolves from discontinuous static recrystallization and continuous static recrystallization(cSRX)to metadynamic recrystallization and cSRX,and finally to cSRX.The cSRX exists at all temperatures.This is because high stacking fault energy(56 mJ m−2)promotes the movement of dislocations,making the deformation mechanism of this steel is dominated by planar slip of dislocation.Large undissolved sigma precipitates promote static recrystallization through particle-stimulated nucleation.However,small strain-induced precipitates at grain boundaries hinder the nucleation of conventional SRX and the growth of recrystallized grains,while the hindering effect decreases with the increase in temperature.

关键词： 7Mo super-austenitic stainless steel Double-stage hot deformation Conventional static recrystallization Metadynamic recrystallization Strain-induced precipitation