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On the Spectrum of Mutually r-orthogonal Idempotent Latin Squares

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Acta Mathematicae Applicatae sinica 2015年第3期31卷 813-822页

作者： yun-qing xu Mathematics Department Ningbo University

Two Latin squares of order v are r-orthogonal if their superposition produces exactly r distinct ordered pairs. The two squares are said to be r-orthogonal idempotent Latin squares and denoted by r-MOILS（v）if they are all idempotent. In this paper, we show that for any integer v≥28, there exists an r-MOILS（v） if and only if r∈[v, v^2]／ {v ＋ 1, v^2-1}.

关键词： Latin square r-orthogonal idempotent

Melatonin Augments the Effects of Fluoxetine on Depression-Like Behavior and Hippocampal BDNF–TrkB signaling

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Neuroscience Bulletin 2018年第2期34卷 303-311页

作者： Kun Li si Shen Yu-Tian Ji xu-yun Li Li-San Zhang Xiao-Dong Wang Department of Neurobiology Key Laboratory of Medical Neurobiology of the Ministry of Health of China Zhejiang Province Key Laboratory of Neurobiology Zhejiang University School of Medicine Hangzhou 310058 China Zhejiang University School of Medicine Hangzhou 310058China Experimental Teaching Center of Basic Medicine Zhejiang University School of Medicine Hangzhou 310058 China Department of Neurology Sir Run Run Shaw HospitalZhejiang University School of Medicine Hangzhou 310016China

Depression is a debilitating psychiatric disorder with a huge socioeconomic burden, and its treatment relies on antidepressants including selective serotonin reuptake inhibitors(SSRIs). Recently, the melatonergic system that is closely associated with the serotonergic system has been implicated in the pathophysiology and treatment of depression. However, it remains unknown whether combined treatment with SSRI and melatonin has synergistic antidepressant effects. In this study, we applied a sub-chronic restraint stress paradigm, and evaluated the potential antidepressant effects of combined fluoxetine and melatonin in adult male mice. Sub-chronic restraint stress(6 h/day for 10 days) induced depression-like behavior as shown by deteriorated fur state, increased latency to groom in the splash test, and increased immobility time in the forced-swim test. Repeated administration of either fluoxetine or melatonin at 10 mg/kg during stress exposure failed to prevent depression-like phenotypes. However,combined treatment with fluoxetine and melatonin at theselected dose attenuated stress-induced behavioral abnormalities. Moreover, we found that the antidepressant effects of combined treatment were associated with the normalization of brain-derived neurotrophic factor(BDNF)–tropomyosin receptor kinase B(Trk B) signaling in the hippocampus, but not in the prefrontal cortex. Our findings suggest that combined fluoxetine and melatonin treatment exerts synergistic antidepressant effects possibly by restoring hippocampal BDNF–Trk B signaling.

关键词： Melatonin Fluoxetine Depression BDNF TrkB

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基于特征增强和样本充分学习的红外飞机检测

电光与控制 2025年第1期32卷 54-60页

作者：徐红鹏刘刚司起峰陈会祥河南科技大学信息工程学院河南洛阳471000

针对深度学习单阶段检测算法对红外飞机目标的特征提取能力不足以及样本学习不充分的问题,提出基于特征增强的全局上下文机制(FEGCM)和样本充分学习的目标检测算法。FEGCM可获取包含目标的全局信息与局部信息的特征图,从而提高特征提取... 详细信息

针对深度学习单阶段检测算法对红外飞机目标的特征提取能力不足以及样本学习不充分的问题,提出基于特征增强的全局上下文机制(FEGCM)和样本充分学习的目标检测算法。FEGCM可获取包含目标的全局信息与局部信息的特征图,从而提高特征提取网络对目标特征的提取能力。通过在Focal Loss中添加调制因子,在关注难负样本学习的基础上,充分利用包含目标特性的部分易负样本,使得样本充分学习,从而帮助检测算法学习到更有意义的目标特征。实验表明,所提算法在自制红外飞机数据集上的mAP_(50)达到96.9%,能够有效实现红外飞机目标检测。

关键词：红外飞机检测全局上下文空间注意力 Focal Loss 易负样本

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Vector Spatiotemporal Solitons and Their Memory Features in Cold Rydberg Gases

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Chinese Physics Letters 2022年第3期39卷 22-27页

作者： Yuan Zhao yun-Bin Lei Yu-Xi xu si-Liu xu Houria Triki Anjan Biswas Qin Zhou School of Electronic and Information Engineering Hubei University of Science and TechnologyXianning 437100China School of International Education Wuhan University of TechnologyWuhan 430071China Radiation Physics Laboratory Department of PhysicsFaculty of SciencesBadji Mokhtar UniversityP.O.Box 1223000 AnnabaAlgeria Department of Physics Chemistry and MathematicsAlabama A&M UniversityNormalAL 35762-4900USA Mathematical Modeling and Applied Computation(MMAC)Research Group Department of MathematicsKing Abdulaziz UniversityJeddah 21589Saudi Arabia School of Mathematical and Physical Sciences Wuhan Textile UniversityWuhan 430200China

We propose a scheme to generate stable vector spatiotemporal solitons through a Rydberg electromagnetically induced transparency(Rydberg-EIT)***-dimensional vector monopole and vortex solitons have been found under three nonlocal *** numerical calculation and analytical solutions indicate that these solitons are generated with low energy and can stably propagate along the *** behavior of vector spatiotemporal solitons can be manipulated by the local and nonlocal *** results show a memory feature as these solitons can be stored and retrieved effectively by tuning the control field.

关键词： field Rydberg solitons

Prompt optical emission from gamma-ray bursts with multiple timescale variability of central engine activities

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Research in Astronomy and Astrophysics 2014年第4期14卷 411-422页

作者： si-Yao xu Zhuo Li Department of Astronomy and Kavli Institute for Astronomy and Astrophysics Peking University Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences

Complete high-resolution light curves of GRB 080319B observed by Swift present an opportunity for detailed temporal analysis of prompt optical emission. With a two-component distribution of initial Lorentz factors, we simulate the dynamical process of shells being ejected from the central engine in the framework of the in- ternal shock model. The emitted radiations are decomposed into different frequency ranges for a temporal correlation analysis between the light curves in different energy bands. The resulting prompt optical and gamma-ray emissions show similar tempo- ral profiles, with both showing a superposition of a component with slow variability and a component with fast variability, except that the gamma-ray light curve is much more variable than its optical counterpart. The variability in the simulated light curves and the strong correlation with a time lag between the optical and gamma-ray emis- sions are in good agreement with observations of GRB 080319B. Our simulations suggest that the variations seen in the light curves stem from the temporal structure of the shells injected from the central engine of gamma-ray bursts. Future observations with high temporal resolution of prompt optical emission from GRBs, e.g., by UFFO- Pathfinder and SVOM-GWAC, will provide a useful tool for investigating the central engine activity.

关键词： gamma rays: bursts- GRB 080319B

Superhydrophobic and corrosion-resistant siloxane-modified MgAl-LDHs coatings on magnesium alloy prepared under mild conditions

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 450-463页

作者： Wenxi Zhang Zhangzelong Zhuo Dan xu Liang Wu Zhihui Xie Chemical Synthesis and Pollution Control Key Laboratory of sichuan Province College of Chemistry and Chemical EngineeringChina West Normal UniversityNanchong 637002China College of Materials Science and Engineering/National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China

We have developed a superhydrophobic and corrosion-resistant LDH-W/PFDTMS composite coating on the surface of Mg *** composite comprised a tungstate-intercalated(LDH-W)underlayer that was grown at low temperature(relative to hydrothermal reaction conditions)under atmospheric pressure and an outer polysiloxane layer created from a solution containing perfluorodecyltrimethoxysilane(PFDTMS)using a simple immersion *** successful intercalation of tungstate into the LDH phase and the following formation of the polysiloxane layer were confirmed through X-ray diffraction(XRD),Fourier transform infrared(FTIR)spectroscopy,and X-ray photoelectron spectroscopy(XPS).The corrosion resistance of the LDH-W film,both before and after the PFDTMS modification,was evaluated using electrochemical impedance spectroscopy(EIS),Tafel curves,and immersion *** results showed that Mg coated with LDH-W/PFDTMS exhibited significantly enhanced corrosion protection compared to the unmodified LDHW film,with no apparent signs of corrosion after exposure to 3.5wt%NaCl solution for 15 ***,the LDH-W/PFDTMS coating demonstrated superior superhydrophobicity and self-cleaning properties against water and several common beverages,as confirmed by static contact angle and water-repellency *** results offer valuable insights into preparing superhydrophobic and corrosion-resistant LDH-based composite coatings on Mg alloy surfaces under relatively mild reaction conditions.

关键词： Mg alloy corrosion coating layered double hydroxide

Two new steroidal glucosides from Ophiopogon japonicus (L.f.) Ker-Gawl

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Chinese Chemical Letters 2008年第7期19卷 825-828页

作者： Ya Jiuan xu Tun Hai xu Ling Zhu Hao Hong Feng Zhao Sheng xu Xie yun Shan si Dong Han Dong Ming xu Academy of Traditional Chinese Medicine and Material Medica of Jilin Province Changchun 130021China School of Traditional Chinese Medicine Beijing University of Chinese Medicine Beijing 100102China School of Traditional Chinese Medicine Xinjiang University of Medicine Urumchi 830011 China

Two new steroidal glucosides, 26-O-β-D-glucopyranosyl （25S）-furost-5-ene-1β,3β,22α,26-tetraol l-O-β-D-xylopyranosyl- （1 → 3）-[α-h-rhamnopyranosyl-（1 → 2）]-[β-D-fueopyranoside and （25R） spirost-5-ene-3β,14α-diol-3-β-O-β-L-rhanmopyranosyl- （1 → 2）-[β-D-xylopyranosyl（1 → 4）]-[-β-D-glucopyranoside, were isolated from the Ophiopogon japonicus （L.f.） Ker-Gaw. Their structures were elucidated by spectroscopic methods.

关键词： Ophiopogon japonicus (L.f.) Ker-Gawl Steroidal glucosides Liliaceae

Rock fracture mechanism of buffer blasting with cushion layer at the borehole bottom

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 325-334页

作者： Xinguang Zhu Chenxi Ding Zhe Sui Hong Su xu Guo School of Civil and Resources Engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 100083China School of Chemical and Blasting Engineering Anhui University of Science and TechnologyHuainan 232001China

This study primarily investigates the rock fracture mechanism of bottom cushion layer blasting and explores the effects of the bottom cushion layer on rock *** involves analyses of the evolution patterns of blasting stress,characteristics of crack distribution,and rock fracture features in the ***,blasting model experiments were carried out using the dynamic caustics principle to investigate the influence of bottom cushion layers and initiation methods on the integrity of the bottom rock *** experimental results indicate that the combined use of bottom cushion layers and inverse initiation effectively protects the integrity of the bottom rock ***,the process of stress wave propagation and dynamic crack propagation in rocks was simulated using the continuum-discontinuum element method(CDEM)and the Landau explosion source model,with varying thicknesses of bottom cushion *** numerical simulation results indicate that with increasing cushion thickness,the absorption of energy generated by the explosion becomes more pronounced,resulting in fewer cracks in the bottom rock *** illustrates the positive role of the cushion layer in protecting the integrity of the bottom rock mass.

关键词： bottom cushion layer blasting crack propagation continuum-discontinuum element method dynamic stress intensity factor

Multi-stage constant current charging strategy considering SOC intervals and voltage thresholds

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Global Energy Interconnection 2022年第2期5卷 143-153页

作者： Yu Zhang si xu Tiezhou Wu Hubei University of Technology Hubei Key Laboratory of Solar Energy Efficient Utilization and Energy Storage Operation ControlHubeiWuhan 430068P.R.China

Conventional multi-stage constant current charging strategies often use higher multiples of current to charge the battery in pursuit of shorter charging ***,this leads to an increase in battery temperature,while shortening the charging *** in turn affects the safety of the charging ***,the higher charging currents are not ideal for shortening the charging time in the later stages of *** solve the aforementioned problems,in this study,a multi-stage constant current charging strategy is *** strategy can shorten the battery charging time by using the increase in battery temperature during the charging process as a constraint,using a genetic algorithm to calculate the charging current value,and investigating the phased approach to ***,the charging strategy is experimentally validated at different ambient temperatures and different initial *** experimental results show that the charging strategy proposed in this paper not only reduces the amount of calculations,but also reduces the temperature rise by up to 46.4%and charging time by up to 4.2%under different operating conditions.

关键词： Charging time Battery temperature rise Genetic algorithm Multi-stage constant current charging