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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 358-378页

作者： Jin-yan ZHU yong CHEN School of Mathematical Sciences Shanghai Key Laboratory of Pure Mathematics and Mathematical PracticeEast China Normal UniversityShanghai 200062China College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao 266590China

The Gerdjikov-Ivanov(GI)hierarchy is derived via recursion operator,in this article,we mainly investigate the third-order flow GI equation.In the framework of the Riemann-Hilbert method,the soliton matrices of the third-order flow GI equation with simple zeros and elementary high-order zeros of Riemann-Hilbert problem are constructed through the standard dressing process.Taking advantage of this result,some properties and asymptotic analysis of single soliton solution and two soliton solution are discussed,and the simple elastic interaction of two soliton are proved.Compared with soliton solution of the classical second-order flow,we find that the higher-order dispersion term affects the propagation velocity,propagation direction and amplitude of the soliton.Finally,by means of a certain limit technique,the high-order soliton solution matrix for the third-order flow GI equation is derived.

关键词： Gerdjikov-Ivanov hierarchy third-order flow GI equation Riemann-Hilbert method high-order soliton

Prefrontocortical Astrocytes Regulate Dominance Hierarchy in Male Mice

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Neuroscience Bulletin 2024年第3期40卷 415-417页

作者： yong Tang Hai-yan Yin Peter Illes School of Acupuncture and Tuina Chengdu University of Traditional Chinese MedicineChengdu 610075China International Joint Research Center on Purinergic Signaling Chengdu University of Traditional Chinese MedicineChengdu 610075China Rudolf Boehm Institute for Pharmacology and Toxicology University of Leipzig04107 LeipzigGermany

Social hierarchy is a general self-organizational scheme in animal societies in which each member achieves a certain status of domination or subordination when getting access to resources,with profound consequences for survival,health,reproductive success,and multiple behaviors[1,2].The prefrontal cortex(PFC)was recognized as a central regulator of neuronal circuits determining the formation of social hierarchy;brain areas upstream of the PFC convey information about social status,and downstream brain regions execute dominance behavior[3].Social deficits have been suggested to be due to an elevation of excitatory/inhibitory(E/l)balance within the mouse dorsomedial(dm)PFC[4].A compensatory increase of inhibitory cell excitability partially rescued social deficits caused by such a disturbance of E/l balance.

关键词： consequences hierarchy determining

Extending Structures for Gel'fand-Dorfman Bialgebras

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Acta Mathematica Sinica,English Series 2024年第2期40卷 619-638页

作者： Jia Jia WEN yan yong HONG School of Mathematics Hangzhou Normal UniversityHangzhou 311121P.R.China

Gel'fand-Dorfman bialgebra,which is both a Lie algebra and a Novikov algebra with some compatibility condition,appeared in the study of Hamiltonian pairs in completely integrable systems.They also emerged in the description of a class special Lie conformal algebras called quadratic Lie conformal algebras.In this paper,we investigate the extending structures problem for Gel'fand-Dorfman bialgebras,which is equivalent to some extending structures problem of quadratic Lie conformal algebras.Explicitly,given a Gel'fand-Dorfman bialgebra(A,o,[.,.]),this problem is how to describe and classify all Gel'fand-Dorfman bialgebra structures on a vector space E(A⊂E)such that(A,o,[.,.])is a subalgebra of E up to an isomorphism whose restriction on A is the identity map.Motivated by the theories of extending structures for Lie algebras and Novikov algebras,we construct an object gH2(V,A)to answer the extending structures problem by introducing the notion of a unified product for Gel'fand-Dorfman bialgebras,where V is a complement of A in E.In particular,we investigate the special case when dim(V)=1 in detail.

关键词： Gel'fand-Dorfman bialgebra Lie conformal algebra Extending structures problem Novikovalgebra

Broadband high-efficiency plasmonic metalens with negative dispersion characteristic

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Photonics Research 2024年第4期12卷 813-820页

作者： yong-QIANG LIU yong ZHU HONGCHENG YIN JINHAI SUN yan WANG yongXING CHE National Key Laboratory of Scattering and Radiation Beijing 100854China

Controlling the dispersion characteristic of metasurfaces(or metalenses) along a broad bandwidth is of great importance to develop high-performance broadband metadevices. Different from traditional lenses that rely on the material refractive index along the light trajectory, metasurfaces or metalenses provide a new regime of dispersion control via a sub-wavelength metastructure, which is known as negative chromatic dispersion.However, broadband metalenses design with high-performance focusing especially with a reduced device dimension is a significant challenge in society. Here, we design, fabricate, and demonstrate a broadband highperformance diffractive-type plasmonic metalens based on a circular split-ring resonator metasurface with a relative working bandwidth of 28.6%. The metalens thickness is only 0.09λ0(λ0is at the central wavelength),which is much thinner than previous broadband all-dielectric metalenses. The full-wave simulation results show that both high transmissive efficiency above 80%(the maximum is even above 90%) and high average focusing efficiency above 45%(the maximum is 56%) are achieved within the entire working bandwidth of 9–12 GHz.Moreover, an average high numerical aperture of 0.7(NA = 0.7) of high-efficiency microwave metalens is obtained in the simulations. The broadband high-performance metalens is also fabricated and experimental measurements verify its much higher average focusing efficiency of 55%(the maximum is above 65% within the broad bandwidth) and a moderate high NA of 0.6. The proposed plasmonic metalens can facilitate the development of wavelength-dependent broadband diffractive devices and is also meaningful to further studies on arbitrary dispersion control in diffractive optics based on plasmonic metasurfaces.

关键词： resonator dispersion high

Empirical likelihood for spatial cross-sectional data models with matrix exponential spatial specification

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 125-139页

作者： LIU yan RONG Jian-rong QIN yong-song Nanning University Nanning 530200China Center for Applied Mathematics of Guangxi and College of Mathematics and Statistics Guangxi Normal UniversityGuilin 541004China

In this paper,we study spatial cross-sectional data models in the form of matrix exponential spatial specification(MESS),where MESS appears in both dependent and error terms.The empirical likelihood(EL)ratio statistics are established for the parameters of the MESS model.It is shown that the limiting distributions of EL ratio statistics follow chi-square distributions,which are used to construct the confidence regions of model parameters.Simulation experiments are conducted to compare the performances of confidence regions based on EL method and normal approximation method.

关键词： MESS empirical likelihood con dence region

Optimal V_(2)O_(3) extraction by sustainable vanadate electrolysis in molten salts

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Tungsten 2024年第1期6卷 141-149页

作者： Bao-yan Feng Zhong-Hua Zhao yong-Zheng Jia Jia-Liang An Ming-yong Wang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory of Green Recovery and Extraction of Rare and Precious Metals University of Science and Technology BeijingBeijing 100083China

Recently,an environmentally friendly electrolysis process of soluble vanadates is proposed and successfully confirmed for V_(2)O_(3) extraction.In this paper,the solubilities of various vanadates(i.e.NaVO_(3),Na_(4)V_(2)O_(7) and Na_(3)VO_(4))in NaCl molten salt are measured.The dependences of V_(2)O_(3) extraction on vanadate form,anode material and molten salt system are studied.A long-term electrolysis is carried out.The result indicates that the solubilities of all vanadates are high and meet electrolytic requirements.Compared to Na_(4)V_(2)O_(7) and Na_(3)VO_(4),NaVO_(3) exhibits larger current efficiency and lower electricity consumption.By using SnO_(2) anode instead of graphite anode,the current efficiency of NaVO_(3) electrolysis can be increased to 58.1%and carbon pollution is avoided at 700℃.The extraction rate of V_(2)O_(3) reaches 81.3%after long-term electrolysis of 51 h.This work optimizes the electrochemical preparation process of V_(2)O_(3) from various vanadates and contributes to the improvement of current efficiency and extraction rate.

关键词： Molten salt electrolysis Vanadate Vanadium trioxide Current efficiency

Metallogenesis of the Baidi Au-Sb deposit, southwest Guizhou Province, China: mineralogical and geochemical evidence from sulfur-bearing minerals

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Acta Geochimica 2024年第2期43卷 199-213页

作者： Jun yan yong Xia Qinping Tan Zhuojun Xie Guosong Ji State KeyLaboratory of Ore Deposit Geochemistry Institute of GeochemistryChineseAcademy of SciencesGuiyang 550081China Guizhou InstituteofTechnology Guiyang550003China No.102 GeologicalTeam Guizhou Bureau of Geologyand Mineral Exploration&DevelopmentZunyi563003China

The Baidi Au-Sb deposit, which contains 8 t of Au and 10,979 Mt of Sb, is a typical and rare paragenetic deposit located in southwestern Guizhou Province, China.Previous studies have focused on individual ores, but have not combined them to identify their paragenetic mechanism or metallogenic regularity. Therefore, we used field investigations, microscopic observations, and in situ analyses to identify the spatial distribution, mineral paragenesis, compositional evolution, and metallogenic material sources of the ore bodies. We also determined the Au and Sb paragenetic characteristics and the metallogenesis of the deposit. The main Au-bearing minerals in the deposit were early(Apy1–2) and late(Apy3) stage arsenopyrites, as well as pre-mineralization(Py1), mineralization(Py2–5), and late mineralization(Py6–7) stage pyrites. The main Sb-bearing minerals were stibnite(Snt), skinnerite, bournonite,and valentinite. The minerals formed in the order of Py1,Py2–3 + Apy1, Py4–5 + Apy2, Snt, and Py6–7 + Apy3.The δ34S values of the arsenopyrites and pyrites ranged from-5 to 5‰, while those of stibnite were mostly less than-5‰ in the later mineralization stages. Sulfur was provided by deep magmatic hydrothermal fluids, but sedimentary sulfur was added in the later stages. Moreover,the trace elemental contents fluctuated and eventually became similar to those of the sedimentary strata. By comprehensively considering the ores along with the geological characteristics of the deposit, we determined that deep magma provided the Au during ore formation. Later tectonic changes provided Sb from the sedimentary strata,which precipitated along fault expansion areas and produced Au and Sb paragenesis.

关键词： Au-Sb mineralization Arsenopyrite Pyrite Stibnite Metallogenetic process

Interaction between systemic iron parameters and left ventricular structure and function in the preserved ejection fraction population:a two-sample bidirectional Mendelian randomization study

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Journal of Geriatric Cardiology 2024年第1期21卷 64-80页

作者： Xiong-Bin MA yong-Ming LIU yan-Lin LV Lin QIAN The First Clinical Medical College of Lanzhou University LanzhouGansuChina Geriatric Cardiovascular Department and Gansu Clinical Research Center for Geriatric Diseases First Hospital of Lanzhou UniversityGansuChina

BACKGROUND Left ventricular(LV)remodeling and diastolic function in people with heart failure(HF)are correlated with iron status;however,the causality is uncertain.This Mendelian randomization(MR)study investigated the bidirectional causal relationship between systemic iron parameters and LV structure and function in a preserved ejection fraction population.METHODS Transferrin saturation(TSAT),total iron binding capacity(TIBC),and serum iron and ferritin levels were extracted as instrumental variables for iron parameters from meta-analyses of public genome-wide association studies.Individuals without myocardial infarction history,HF,or LV ejection fraction(LVEF)<50%(n=16,923)in the UK Biobank Cardiovascular Magnetic Resonance Imaging Study constituted the outcome dataset.The dataset included LV end-diastolic volume,LV endsystolic volume,LV mass(LVM),and LVM-to-end-diastolic volume ratio(LVMVR).We used a two-sample bidirectional MR study with inverse variance weighting(IVW)as the primary analysis method and estimation methods using different algorithms to improve the robustness of the results.RESULTS In the IVW analysis,one standard deviation(SD)increased in TSAT significantly correlated with decreased LVMVR(β=-0.1365;95%confidence interval[CI]:-0.2092 to-0.0638;P=0.0002)after Bonferroni adjustment.Conversely,no significant relationships were observed between other iron and LV parameters.After Bonferroni correction,reverse MR analysis showed that one SD increase in LVEF significantly correlated with decreased TSAT(β=-0.0699;95%CI:-0.1087 to-0.0311;P=0.0004).No heterogeneity or pleiotropic effects evidence was observed in the analysis.CONCLUSIONS We demonstrated a causal relationship between TSAT and LV remodeling and function in a preserved ejection fraction population.

关键词： fraction function parameters

Effect of Al_(2)O_(3)fiber on twin intersections-induced dynamic recrystallization in fine-grained TiAl matrix composite

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Journal of Materials Science & Technology 2024年第5期172卷 1-14页

作者： Yaofeng Luo yan Wang Li Wang Bin Liu yong Liu State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

Dynamic recrystallization(DRX)is of great significance for the thermomechanical processing and microstructural regulation of TiAl intermetallics.However,the underlying DRX mechanism remains poorly understood.In this study,an Avrami kinetics model for DRX was established,which was capable of predicting the DRX fraction accurately.In addition,the effect of Al_(2)O_(3)short fiber on the DRX mechanisms of TiAl matrix composite during the isothermal compression was investigated for the first time.The re-sults showed that other than inhibiting DRX by particles in the TiAl matrix composites,the addition of Al_(2)O_(3)short fiber accelerated a novel DRX process,which was induced by twinning and twin intersec-tions(TDRX).Thus,this composite exhibited a higher DRX rate than that of the as-cast TiAl monolithic alloy.The origin of the twin intersection and TDRX for the composite was revealed.The stress concentration near the Al_(2)O_(3)fiber was above the critical shear stress for twinning and thus was favorable for the formation of twinning and twin intersections.The high stored strain energy at the regions of twins and twin intersections provided the driving force for TDRX.TDRX accelerated the grain refinement in the TiAl matrix near the Al_(2)O_(3)fiber.The present findings would provide a new perspective on DRX mechanisms,and provide the scientific guidance for optimizing the microstructures of TiAl matrix composites.

关键词： TiAl matrix composite Al_(2)O_(3)fiber Twin intersection Dynamic recrystallization

Application and progress of artificial intelligence technology in the segmentation of hyperreflective foci in OCT images for ophthalmic disease research

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International Journal of Ophthalmology(English edition) 2024年第6期17卷 1138-1143页

作者： Jia-Ning Ying Hu Li yan-yan Zhang Wen-Die Li Quan-yong Yi Ningbo Eye Hospital Wenzhou Medical UniversityNingbo 315042Zhejiang ProvinceChina Health Science Center Ningbo UniversityNingbo 315211Zhejiang ProvinceChina

With the advancement of retinal imaging,hyperreflective foci(HRF)on optical coherence tomography(OCT)images have gained significant attention as potential biological biomarkers for retinal neuroinflammation.However,these biomarkers,represented by HRF,present pose challenges in terms of localization,quantification,and require substantial time and resources.In recent years,the progress and utilization of artificial intelligence(AI)have provided powerful tools for the analysis of biological markers.AI technology enables use machine learning(ML),deep learning(DL)and other technologies to precise characterization of changes in biological biomarkers during disease progression and facilitates quantitative assessments.Based on ophthalmic images,AI has significant implications for early screening,diagnostic grading,treatment efficacy evaluation,treatment recommendations,and prognosis development in common ophthalmic diseases.Moreover,it will help reduce the reliance of the healthcare system on human labor,which has the potential to simplify and expedite clinical trials,enhance the reliability and professionalism of disease management,and improve the prediction of adverse events.This article offers a comprehensive review of the application of AI in combination with HRF on OCT images in ophthalmic diseases including age-related macular degeneration(AMD),diabetic macular edema(DME),retinal vein occlusion(RVO)and other retinal diseases and presents prospects for their utilization.

关键词： artificial intelligence deep learning hyperreflective foci image analysis