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Prenatal cadmium exposure impairs neural tube closure via inducing excessive apoptosis in neuroepithelium

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Journal of Environmental Sciences 2024年第4期138卷 572-584页

作者： Shiyong Zhu Xuenan li Xueyan Dai Jinlong li College of Veterinary Medicine Northeast Agricultural UniversityHarbin 150030China Key Laboratory of the Provincial Education Department of Heilongjiang for Common Animal Disease Prevention and Treatment Northeast Agricultural UniversityHarbin 150030China Heilongjiang Key Laboratory for Laboratory Animals and Comparative Medicine Northeast Agricultural UniversityHarbin 150030China

Birth defects have become a public health *** hazardous environmental factors exposure to embryos could increase the risk of birth ***,a toxic environmental factor,can cross the placental barrier during *** woman may be subjected to cadmium before taking precautionary protective ***,the link between birth defects and cadmium remains *** exposure can induce excessive apoptosis in neuroepithelium during embryonic development *** exposure activated the p53 via enhancing the adenosine 5‘-monophosphate(AMP)-activated protein kinase(AMPK)and reactive oxygen species'(ROS)*** cadmium decreases the level of Paired box 3(Pax3)and murine double minute 2(Mdm2),disrupting the process of p53 *** p53 accumulation induced excessive apoptosis in neuroepithelium during embryonic development *** apoptosis led to the failure of neural tube *** study emphasizes that environmental materials may increase the health risk for *** caused the failure of neural tube closure during early embryotic *** women may be exposed by cadmium before taking precautionary protective actions,because of cadmium concentration-containing foods and environmental tobacco *** suggests that prenatal cadmium exposure is a threatening risk factor for birth defects.

关键词： Cadmium Neural tube closure Excessive apoptosis p53 Embryogenesis

Controllable CPL response driven by achiral UV-photosensitive dichroic dye through cholesteric liquid crystals

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Science China Chemistry 2024年第4期67卷 1250-1255页

作者： Yihan Chen Yang li Hang li Lulu li Yiwu Quan Yixiang Cheng State Key Laboratory of Analytical Chemistry for life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Key Laboratory of High-Performance Polymer Material and Technology of Ministry of Education School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

Versatile stimuli-responsive circularly polarized luminescent(CPL)materials have potential applications in information storage,security encryption,and intelligent *** this study,the Z/E isomerization of ultraviolet(UV)-photosensitive achiralα-cyanostilbene derivative was used as an achiral dichroic dye(Switch)to drive the controllable CPL-active response in cholesteric liquid crystals(CLCs).Under irradiation by 365 nm UV light,the resulting CLCs-Z-Switch underwent a Z-to-E configuration isomerization as CLCs-E-Switch,accompanied by a decrease in its dichroic order parameter(SFvalue)from 0.15to *** the quantum yield(QY)of CLCs-E-Switch increased from 8.1%(CLCs-Z-Switch)to 16.8%,the corresponding glumvalues of CPL emission decreased from+0.55/-0.57 to+0.37/-0.39 due to a decrease in the order of helical arrangement of E-Switch in E7 *** study enables photosensitive CLCs-Switch to be applied for optical information storage devices.

关键词： circularly polarized luminescent photosensitive dichroic dye cholesteric liquid crystals chiral induction

Style-conditioned music generation with Transformer-GANs

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Frontiers of Information Technology & Electronic Engineering 2024年第1期25卷 106-120页

作者： Weining WANG Jiahui li Yifan li Xiaofen XING School of Electronic and Information Engineering South China University of TechnologyGuangzhou 510600China

Recently,various algorithms have been developed for generating appealing ***,the style control in the generation process has been somewhat *** style refers to the representative and unique appearance presented by a musical work,and it is one of the most salient qualities of *** this paper,we propose an innovative music generation algorithm capable of creating a complete musical composition from scratch based on a specified target style.A style-conditioned linear Transformer and a style-conditioned patch discriminator are introduced in the *** style-conditioned linear Transformer models musical instrument digital interface(MIDI)event sequences and emphasizes the role of style ***,the style-conditioned patch discriminator applies an adversarial learning mechanism with two innovative loss functions to enhance the modeling of music ***,we establish a discriminative metric for the first time,enabling the evaluation of the generated music’s consistency concerning music *** objective and subjective evaluations of our experimental results indicate that our method’s performance with regard to music production is better than the performances encountered in the case of music production with the use of state-of-the-art methods in available public datasets.

关键词： Music generation Style-conditioned Transformer Music emotion

Simplified design of nonlinear damper parameters and seismic responses for long-span cable-stayed bridges with nonlinear viscous dampers

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 1103-1116页

作者： Huihui li lifeng li Rui HU Meng YE College of Civil and Transportation Engineering Shenzhen UniversityShenzhen 518060China Guangdong Provincial Key Laboratory of Durability for Marine Civil Engineering Shenzhen UniversityShenzhen 518060China College of Civil Engineering Hunan UniversityChangsha 410082China

Viscous dampers are widely used as passive energy dissipation devices for long-span cable-stayed bridges for mitigation of seismic load-induced ***,complicated finite element(FE)modeling,together with repetitive and computationally intensive nonlinear time-history analyses(NTHAs)are generally required in conventional design *** streamline the preliminary design process,this paper developed a simplified longitudinal double degree of freedom model(DDFM)for single and symmetric twin-tower cable-stayed *** on the proposed simplified longitudinal DDFM,the analytical equations for the relevant mass-and stiffness-related parameters and longitudinal natural frequencies of the structure were derived by using analytical and energy *** of the relationship between the nonlinear viscous damper parameters and the equivalent damping ratio was achieved through the equivalent linearization ***,the analytical equations of longitudinal seismic responses for long-span cable-stayed bridges with nonlinear viscous dampers were *** on the developed simplified DDFM and suggested analytical equations,this paper proposed a simplified calculation framework to achieve a simplified design method of nonlinear viscous damper ***,the effectiveness and applicability of the developed simplified longitudinal DDFM and the proposed calculation framework were further validated through numerical analysis of a practical cable-stayed ***,the results indicated the following.1)For the obtained fundamental period and longitudinal stiffness,the differences between results of the simplified longitudinal DDFM and numerical analysis were only 2.05%and 1.5%,respectively.2)Relative calculation errors of the longitudinal girder-end displacement and bending moment of the bottom tower section of the bridge obtained from the simplified longitudinal DDFM were limited to less than 25%.3)The equivalent damping ratio of nonline

关键词： cable-stayed bridges viscous dampers simplified analytical model equivalent damping ratio seismic mitigation

Metallurgical performance evaluation of space-weathered Chang’e-5 lunar soil

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1241-1248页

作者： Chen li Wenhui Ma Yang li Kuixian Wei Center for Lunar and Planetary Sciences Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming 650093China

Space metallurgy is an interdisciplinary field that combines planetary space science and metallurgical *** involves systematic and theoretical engineering technology for utilizing planetary resources in ***,space metallurgy on the Moon is challenging because the lunar surface has experienced space weathering due to the lack of atmosphere and magnetic field,making the mi-crostructure of lunar soil differ from that of minerals on the *** this study,scanning electron microscopy and transmission electron microscopy analyses were performed on Chang’e-5 powder lunar soil *** microstructural characteristics of the lunar soil may drastically change its metallurgical *** main special structure of lunar soil minerals include the nanophase iron formed by the impact of micrometeorites,the amorphous layer caused by solar wind injection,and radiation tracks modified by high-energy particle rays inside mineral *** nanophase iron presents a wide distribution,which may have a great impact on the electromagnetic prop-erties of lunar *** ions injected by solar wind may promote the hydrogen reduction *** widely distributed amorph-ous layer and impact glass can promote the melting and diffusion process of lunar ***,although high-energy events on the lun-ar surface transform the lunar soil,they also increase the chemical activity of the lunar *** is a property that earth samples and tradi-tional simulated lunar soil *** application of space metallurgy requires comprehensive consideration of the unique physical and chemical properties of lunar soil.

关键词： space metallurgy Chang’e-5 lunar soil space weathering metallurgical performance

Humic acid-mediated transport of a typical soil passivation remediation product(chloropyromorphite)in saturated porous media

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Journal of Environmental Sciences 2024年第7期141卷 51-62页

作者： Xinying li Mengjia Zhang Siyuan li Wei Wei School of Environment Jiangsu Engineering Lab of Water and Soil Eco-remediationJiangsu Province Engineering Research Center of Environmental Risk Prevention and Emergency Response TechnologyNanjing Normal UniversityNanjing 210023China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China

Conversion of labile Pb species into chloropyromorphite(CPY)using phosphorus-bearing amendments was considered to be an ideal strategy in soil passivation ***,the fate and transport of CPY in the soil are poorly *** study aims to fill the knowledge gap by evaluating the fate and transport of CPY under environmentally relevant conditions of humic acid(HA),pH,electrolyte concentration,and species through the saturated sandy *** showed that bare CPY colloids are basically immobile in sandy porous media while the co-existence of HA made the transport of CPY improved by30%-93.5%.Facilitated transport of CPY was attributed to the increased stability of CPY and the repulsive interaction between CPY particles and sands due to HA *** mobility of CPY was also increased with increasing pH from 5.0 to *** the pH was 9 with a10 mmol/L NaCl background solution,the stronger energy barrier between CPY and sand led to enhanced transport *** divalent Ca^(2+)had a more dramatic effect than monovalent Na^(+)on the aggregation and sedimentation of CPY colloids due to its effectivescreening of the surface charge of CPY and bridging interaction with CPY ***-LandauVerwey-Overbeek theory and attachment efficiency calculation indicated that high energy barriers were responsible for the high mobility of CPY colloids,while the retention of CPY in sands was mainly caused by secondary energy minimum and physically *** findings of this work can help to evaluate the fate of soil passivation remediation products in natural water and soil.

关键词： Chloropyromorphite DLVO theory Stability Saturated porous medium Transport

Auto-parametric resonance of a continuous-beam-bridge model under two-point periodic excitation:an experimental investigation and stability analysis

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 445-454页

作者： li Yuchun Shen Chao liu Wei li Dong Department of Hydraulic Engineering College of Civil EngineeringTongji UniversityShanghai 200092China

The auto-parametric resonance of a continuous-beam bridge model subjected to a two-point periodic excitation is experimentally and numerically investigated in this *** auto-parametric resonance experiment of the test model is conducted to observe and measure the auto-parametric resonance of a continuous beam under a two-point excitation on *** parametric vibration equation is established for the test model using the finite-element *** auto-parametric resonance stability of the structure is analyzed by using Newmark's method and the energy-growth exponent *** effects of the phase difference of the two-point excitation on the stability boundaries of auto-parametric resonance are studied for the test *** with the experiment,the numerical instability predictions of auto-parametric resonance are consistent with the test phenomena,and the numerical stability boundaries of auto-parametric resonance agree with the experimental *** a continuous beam bridge,when the ratio of multipoint excitation frequency(applied to the columns)to natural frequency of the continuous girder is approximately equal to 2,the continuous beam may undergo a strong auto-parametric *** with the present experiment and analysis,a hypothesis of Volgograd Bridge's serpentine vibration is discussed.

关键词： auto-parametric resonance continuous beam bridge model two-point excitation experimental investigation stability analysis vibration of Volgograd Bridge

A novel evasion guidance for hypersonic morphing vehicle via intelligent maneuver strategy

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Chinese Journal of Aeronautics 2024年第5期37卷 441-461页

作者： Xun li Xiaogang WANG Hongyu ZHOU Yu li Department of Aerodynamics Harbin Institute of TechnologyHarbin 150001China Beijing Aerospace Technology Institute Beijing 100074China

This paper presents a novel evasion guidance law for hypersonic morphing vehicles,focusing on determining the optimized wing's unfolded angle to promote maneuverability based on an intelligent ***,the pursuit-evasion problem is modeled as a Markov decision *** the agent's action consists of maneuver overload and the unfolded angle of wings,which is different from the conventional evasion guidance designed for fixed-shape *** reward function is formulated to ensure that the miss distances satisfy the prescribed bounds while minimizing energy ***,to maximize the expected cumulative reward,a residual learning method is proposed based on proximal policy optimization,which integrates the optimal evasion for linear cases as the baseline and trains to optimize the performance for nonlinear engagement with multiple ***,offline training guarantees improvement of the constructed evasion guidance law over conventional ***,the guidance law for online implementation includes only analytical *** maps from the confrontation state to the expected angle of attack and the unfolded angle while retaining high computational *** show that the proposed evasion guidance law can utilize the change of unfolded angle to extend the maximum overload *** it surpasses conventional maneuver strategies by ensuring better evasion efficacy and higher energy efficiency.

关键词： Hypersonic vehicles Variable-sweep wings Evasion guidance Reinforcement learning Pursuit-evasion problem

Optimization of Band Gap of 1D Elastic Metamaterial Under Impact Load by Regulating Stiffness

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Acta Mechanica Solida Sinica 2024年第1期37卷 148-154页

作者： Tong li Xianlong Jin Yongqiang li Peizhong Yang School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Mechanical System and Vibration Shanghai Jiaotong UniversityShanghai 200240China College of Science Northeastern UniversityShenyang 110819China

Designing materials that mitigate impacts effectively are crucial for protecting people and ***,a single-resonator metamaterial with negative mass characteristics is proposed for impact mitigation,and numerical analysis of wave propagation shows explicitly how the spring stiffness and number of unit cells influence that *** results show clearly that a metamaterial with differing microstructural stiffness is better at mitigating the effect of a shock wave than one with a unique ***,there is a critical number of unit cells beyond which the shock wave is not attenuated further,but the fabrication complexity *** the 40 groups of microstructural regions in this example,the attenuation effect no longer increases when there are more than 35 *** work offers guidance for microstructure designs in metamaterials and provides new ideas for using metamaterials to mitigate shock waves.

关键词： Elastic metamaterials Wave attenuation Stiffness Number of unit cells