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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 191-200页

作者： LI Zhi-yu LI Kun CAI Jin-ming QIN jian-fang ZHENG Zhao-wen School of Mathematical Sciences Qufu Normal UniversityQufu 273165China College of Mathematics and Systems Science Guangdong Polytechnic Normal UniversityGuangzhou 510665China

A class of Sturm-Liouville problems with discontinuity is studied in this *** oscillation properties of eigenfunctions for Sturm-Liouville problems with interface conditions are *** main method used in this paper is based on Prufer transformation,which is different from the classical ***,we give two examples to verify our main results.

关键词： Sturm-Liouville problem interface condition oscillatory solution

Inverse Calculation and Regularization Process for the Solar Aspect System(SAS) of HXI Payload on ASO-S Spacecraft

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Research in Astronomy and Astrophysics 2024年第4期24卷 13-34页

作者： Ji-Rui Yu Ping ruan Yang Su Ying-Hong He Jin-You Tao Zhe Zhang Song Guo Bin Xue jian-Feng Yang Xi'an Institute of Optics and Precision Mechanics of Chinese Academy of Sciences Xi'an 710119China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 20034China School ofAstronomy and Space Science Universityof Science and Technology of ChinaHefei 230026China

For the ASO-S/HXI payload, the accuracy of the flare reconstruction is reliant on important factors such as the alignment of the dual grating and the precise measurement of observation orientation. To guarantee optimal functionality of the instrument throughout its life cycle, the Solar Aspect System (SAS) is imperative to ensure that measurements are accurate and reliable. This is achieved by capturing the target motion and utilizing a physical model-based inversion algorithm. However, the SAS optical system’s inversion model is a typical ill-posed inverse problem due to its optical parameters, which results in small target sampling errors triggering unacceptable shifts in the solution. To enhance inversion accuracy and make it more robust against observation errors, we suggest dividing the inversion operation into two stages based on the SAS spot motion model. First, the as-rigid-aspossible (ARAP) transformation algorithm calculates the relative rotations and an intermediate variable between the substrates. Second, we solve an inversion linear equation for the relative translation of the substrates, the offset of the optical axes, and the observation orientation. To address the ill-posed challenge, the Tikhonov method grounded on the discrepancy criterion and the maximum a posteriori (MAP) method founded on the Bayesian framework are utilized. The simulation results exhibit that the ARAP method achieves a solution with a rotational error of roughly±3 5 (1/2-quantile);both regularization techniques are successful in enhancing the stability of the solution, the variance of error in the MAP method is even smaller—it achieves a translational error of approximately±18μm (1/2-quantile) in comparison to the Tikhonov method’s error of around±24μm (1/2-quantile). Furthermore, the SAS practical application data indicates the method’s usability in this study. Lastly, this paper discusses the intrinsic interconnections between the regularization methods.

关键词： methods:data analysis Sun:flares Sun:X-rays gamma rays

Solidification crack characteristics and sensitivity of peritectic steel

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Journal of Iron and Steel Research International 2024年第7期31卷 1668-1679页

作者： Ya-qiang Li jian-hua Liu Zi-ming Wang Ying-ying Li Yang He Xiao-wei Li Department of Automotive Engineering Hebei Vocational University of Technology and EngineeringXingtai 054000HebeiChina Hebei Special Vehicle Modification Technology Innovation Center Hebei Vocational University of Technology and EngineeringXingtai 054000HebeiChina Institute of Engineering Technology University of Science and Technology BeijingBeijing 100083China School of Petroleum and Natural Gas Engineering Changzhou UniversityChangzhou 213164JiangsuChina

The characteristics and sensitivity of solidification cracks in peritectic steels were investigated using directional solidifi-cation *** cracks were observed in both hypoperitectic steels(12CrlMoV,15CrMo)and hyper-peritectic steel(20CrMo)during solidification at growth velocities of 15,50,and 80 pm/*** the dendritic boundaries,sulphide precipitates were found,promoting crack *** on the statistical analysis of interdendritic cracks in peritectic steels,the area ratio(RA)of interdendritic cracks in a directional solidification structure was proposed to evaluate the crack sensitivity of peritectic ***,the crack sensitivities of peritectic steels(12CrlMoV,15CrMo,and 20CrMo)were tested,evaluated,and compared with the surface crack rates of three types of steels produced from a steel *** results demonstrated that RA was in good agreement with that of the steel plant,and the crack sensitivity of 12CrlMoV steel was the strongest,followed by that of 15CrMo and 20CrMo ***,RA can be used to evaluate the crack sensitivity of peritectic steel.

关键词： Peritectic steel-Directional solidification Growth velocity Dendritic structure Solidification crack Crack sensitivity

Endoscopic detection and diagnostic strategies for minute gastric cancer:A real-world observational study

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World Journal of Gastrointestinal Oncology 2024年第8期16卷 3529-3538页

作者： Xiao-Wei Ji Jie Lin Yan-Ting Wang Jing-Jing ruan Jing-Hong Xu Kai Song jian-Shan Mao Department of Gastroenterology The Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310009Zhejiang ProvinceChina Department of Pathology The Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310009Zhejiang ProvinceChina

BACKGROUND Minute gastric cancers(MGCs)have a favorable prognosis,but they are too small to be detected by endoscopy,with a maximum diameter≤5 *** To explore endoscopic detection and diagnostic strategies for *** This was a real-world observational *** endoscopic and clinicopathological parameters of 191 MGCs between January 2015 and December 2022 were retrospectively *** discoverable opportunity and typical neoplastic features were emphatically *** All MGCs in our study were of a single pathological type,97.38%(186/191)of which were differentiated-type *** light endoscopy(WLE)detected 84.29%(161/191)of MGCs,and the most common morphology of MGCs found by WLE was ***-band imaging(NBI)secondary observation detected 14.14%(27/191)of MGCs,and the most common morphology of MGCs found by NBI was *** three MGCs were detected by indigo carmine third *** a well-demarcated border lesion exhibited a typical neoplastic color,such as yellowish-red or whitish under WLE and brownish under NBI,MGCs should be *** proportion with high diagnostic confidence by magnifying endoscopy with NBI(ME-NBI)was significantly higher than the proportion with low diagnostic confidence and the only visible groups(94.19%>56.92%>32.50%,P<0.001).CONCLUSION WLE combined with NBI and indigo carmine are helpful for detection of MGCs.A clear demarcation line combined with a typical neoplastic color using nonmagnifying observation is sufficient for diagnosis of *** improves the endoscopic diagnostic confidence of MGCs.

关键词： Minute gastric cancer White light endoscopy Narrow-band imaging endoscopy Indigo carmine Magnifying endoscopy Detection Diagnosis

Hematuria after nocturnal exercise of a man: A case report

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World Journal of Clinical Cases 2024年第5期12卷 1025-1028页

作者： ming-jian Bai Song-Tao Yang Xue-Kai Liu Department of Clinical Laboratory Aerospace Center HospitalBeijing 100049China Department of Nephrology Aerospace Center HospitalBeijing 100049China

BACKGROUND A man experienced multiple episodes of macroscopic hematuria following nocturnal *** stones and tumors were considered the two most likely *** patient had two hobbies:Consuming health care products in large quantities and engaging in late-night *** SUMMARY Health care products contain a large amount of calcium phosphate,and we hypothesize that this could induce the formation of small phosphate *** exercise,the urinary system is abraded,resulting in *** patient was advised to stop using the health care ***,the aforementioned symptoms disappeared ***,the patient resumed the above two habits one year later;correspondingly,the macroscopic hematuria *** This finding further confirmed the above inference and allowed for a new avenue to determine the cause of the patient’s hematuria.

关键词： Hematuria Health care products Exercise Case report

A Potential Degree Sequence Problem of the Loebl-Komlós-Sós Conjecture

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Acta Mathematicae Applicatae Sinica 2024年

作者： Guang-ming LI jian-hua YIN School of Mathematics and Statistics Hainan University

A non-increasing sequenceπ=(d1,..., dn) of nonnegative integers is said to be a graphic sequence if it is realizable by a simple graph G on n vertices. In this case, G is referred to as a realization ofπ. In terms of graphic sequences, the Loebl-Komlós-Sós conjecture states that for any integers k and n, if π=(d1,..., dn)is a graphic sequence with d「n/2」≥k, then every realization ofπcontains all trees with k edges as *** problem can be viewed as a forcible degree sequence problem. In this paper, we consider a potential degree sequence problem of the Loebl-Komlós-Sós conjecture, that is, we prove that for any integers k and n, ifπ=(d1,..., dn) is a graphic sequence with d「n/2」≥k, then there is a realization ofπcontaining all trees with k edges as subgraphs.

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A general synthetic strategy for N, P co-doped graphene supported metal-rich noble metal phosphides for hydrogen generation

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Green Energy & Environment 2024年第1期9卷 152-162页

作者： Jingwen Ma Xiang Li Guangyu Lei Jun Wang Juan Wang jian Liu ming Ke Yang Li Chunwen Sun School of Chemical and Environmental Engineering China University of Mining and Technology(Beijing)Beijing100083China State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China Lab of Advanced Nano-structures&Transfer Processes Department of Chemical EngineeringTianjin UniversityTianjin300354China PetroChina Planning and Engineering Institute Beijing100083China

The exploitation of electrocatalysts with high activity and durability for HER is desirable for future energy systems,but it is still a *** have attracted increasing attentions,but the preparation process often needs toxic regents or dangerous reaction ***,we develop a general green method to fabricate metal-rich NMPs anchored on NPG through pyrolyzing DNA cross-linked *** obtained Ru_(2) P-NPG exhibits an ultrasmall overpotential of 7 mV at 10 mA cm^(2) and ultralow Tafel slope of 33 mV dec^(-1) in 1.0 mol L?1 KOH,even better than that of commercial Pt/*** addition,Ru 2 P-NPG also shows low overpotentials of 29 and 78 mV in 0.5 mol L^(-1) H_(2)SO_(4) and 1.0 mol L^(-1) PBS,*** superior activity can be attributed to the ultrafine dispersion of Ru 2 P nanoparticles for more accessible sites,more defects formed for abundant active sites,the two-dimensional plane structure for accelerated electron transfer and mass transport,as well as the regulation of electron distribution of the ***,the synthetic method can also be applied to prepare other metal-rich noble metal phosphides(Pd_(3)P-NPG and Rh_(2)P-NPG),which also exhibits high activity for *** work provides an effective strategy for designing NMP-based electrocatalysts.

关键词： Noble metal phosphides Electrocatalyst Deoxyribonucleic acid Hydrogen evolution pH universal

Male reproductive function before and after the adjustment of the COVID-19 prevention policy:a multicenter study in China

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Asian Journal of Andrology 2024年第3期26卷 308-314页

作者： jian-Zheng Li Han Wu Li Wang Yun-Shan Wang Feng Kong Long-Qiao Cao ming Liang Xiong Wang ming-Zhen Yuan Shandong Provincial Hospital Affiliated to Shandong First Medical University Jinan 250000China Institute of Women Children and Reproductive HealthShandong UniversityJinan 250012China Engineering Laboratory of Urinary Organ and Functional Reconstruction of Shandong Province Jinan 250000China The First People’sHospital of Jining Jining 272000China Department of Reproductive Medicine The Second Affiliated Hospital of Shandong University of Traditional Chinese MedicineJinan 250000China Reproductive Medicine Center Affiliated Yantai Yuhuangding Hospital of Qingdao UniversityYantai 264000China

At the end of 2022,the adjustment of the coronavirus disease 2019(COVID-19)pandemic control policy in China resulted in alarge-scale increase in public *** compare the fertility parameters of male patients before and after the adjustments ofthe COVID-19 pandemic control policy in China,we collected data on patients’medical histories and laboratory examinations ontheir first visits between June 2022 and March 2023 in five different *** were divided into five groups according tothe timeline of the policy *** data we collected from male patients included semen quality and serum reproductivehormone levels,and intergroup comparisons were made using the Mann–Whitney U and Chi-square *** total,16784 casesunderwent regular semen analysis,11180 had sperm morphology assessments,and 7200 had reproductive hormone *** showed declining trends in semen volume,sperm motility,and the progressive sperm motility rate after the policy *** comparison revealed an initial decrease and gradual recovery in progressive motility *** morphology analysisshowed increased neck and tail abnormalities after the policy *** significant change in hormone levels was *** the adjustment of the COVID-19 prevention policy in China,a decline in sperm motility and morphology was *** trend may gradually recover over 2 *** the policy adjustment,reproductive hormone levels were relatively stablethroughout,except for an increase in luteinizing hormone(LH).These changes in semen parameters suggest that the policyadjustment had a short-to medium-term impact on male reproductive function.

关键词： COVID-19 multicenter study reproduction SARS-CoV-2 semen analysis

Immunological Exploration of Helicobacter pylori Serotype O_(2) O-Antigen by Using a Synthetic Glycan Library

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Chinese Journal of Chemistry 2024年第3期42卷 243-251页

作者： ming Zhao Guangzong Tian Chunjun Qin Xiaopeng Zou Peter H. Seeberger Jing Hu jian Yin Key Laboratory of Carbohydrate Chemistry and Biotechnology Ministry of EducationSchool of Biotechnology & School of Life Sciences and Health EngineeringJiangnan UniversityLihu Avenue 1800WuxiJiangsu214122 China Biomolecular Systems Department Max Planck Institute of Colloids and InterfacesAm Mühlenberg 1Potsdam14476 Germany Wuxi School of Medicine Jiangnan UniversityLihu Avenue 1800WuxiJiangsu214122 China

Helicobacter pylori(***)infection is a threat to human *** lipopolysaccharide(LPS)O-antigen holds promise for developing *** is meaningful to explore the immunological activity of oligosaccharides with different lengths and frameshifts for antigen ***,a glycan library of *** O2 O-antigen containing eight fragments is *** screening with *** O2 LPS sera and patients’sera by glycan microarray,the disaccharide HPO2G-2b and trisaccharide HPO2G-3a show strong antigenicity and then are separately conjugated with carrier protein *** glycoconjugates elicit a robust immunoglobulin G(IgG)immune response in *** anti-HPO2G-3a IgG antibodies possess a much stronger binding affinity with the LPS and bacteria of *** O2 than the anti-HPO2G-2b IgG *** is no cross-reaction between both sera IgG antibodies with LPS and bacteria of *** O1,O6,and *** results demonstrate the trisaccharide HPO2G-3a is a promising candidate for *** vaccine development.

关键词： Glycoconjugates Helicobacter pylori Immunology Microarrays O-antigen Oligosaccharides

Optimizing magnetoelastic properties by machine learning and high-throughput micromagnetic simulation

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Rare Metals 2024年第5期43卷 2251-2262页

作者： jian-Hu Gong Zheng-ming Zhang Cheng-Liang Zhang Peng-Qiang Hu Chao Zhou Dun-Hui Wang Sen Yang Division of Microelectronic Materials and Devices Hangzhou Dianzi UniversityHangzhou 310018China School of Physics MOEKey Laboratory forNonequilibrium Synthesis and Modulation of Condensed Matter and State Key Laboratory for Mechanical Behavior of MaterialsXi'an Jiaotong UniversityXi'an 710049China National Laboratory of Solid State Microstructures Nanjing UniversityNanjing210093China

Magnetoelastic couplings in giant magnetostrictive materials(GMMs)attract significant interests due to their extensive applications in the fields of spintronics and energy harvesting *** the role of the selection of materials and the response to external fields is essential for attaining desired functionality of a ***,machine learning(ML)models are conducted to predict saturation magnetostrictions(λ_(s))in RFe_(2)-type(R=rare earth)GMMs with different *** to ML-predicted composition–λsrelations,it is discovered that the values ofλshigher than1100×10^(-6)are almost situated in the composition space surrounded by 0.26≤x≤0.60 and 1.90≤y≤2.00 for the ternary compounds of Tb_(x)Dy_(1-x)Fe_(y).Assisted by ML predictions,the compositions are further narrowed down to the space surrounded by 0.26≤x≤0.32 and 1.92≤y≤1.97 for the excellent piezomagnetic(PM)performance in the Tb_(x)Dy_(1-x)Fe_(y)based PM device through our developed high-throughput(HTP)micromagnetic simulation(MMS)***,high sensitivities up to10.22-13.61 m T·MPa^(-1)are observed in the optimized range within which the available experimental data fall *** work not only provides valuable insights toward understanding the mechanism of magnetoelastic couplings,but also paves the way for designing and optimizing highperformance magnetostrictive materials and PM sensing devices.

关键词： Magnetostriction Piezomagnetic effect Machine learning Micromagnetic simulation