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Influential and prognostic factors of small for gestational age infants

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Chinese Medical Journal 2009年第4期122卷 386-389页

作者： ZHANG Yong-li liu jun-tao GAO Jin-song YANG Jian-qiu BIAN Xu-ming Department of Obstetrics and Gynecology Peking Union MedicalCollege Hospital Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100730 China

Background Small for gestational age （SGA） infants are associated with a high rate of oligohydramnios, stillbirth and cesarean delivery. Among SGA patients there is a higher risk of neonatal complications, such as polycythemia, hyperbilirubinemia, and hypothermia. Additionally, the SGA infant is prone to suffer from major neurologic sequelae, as well as cardiovascular system disease, in later life. Proper monitoring and therapy during pregnancy are, therefore, of utmost importance. The present study aimed to investigate the influential and prognostic factors of SGA infants.Methods From January 2001 to june 2007, a total of 55 SGA neonatal infants were included in a study group. All were born at Peking Union Medical College Hospital, with regular formal antenatal examinations. In addition, a total of 122 cases of appropriate for gestational age （AGA） infants were born at the same time and were registered into a control group. All cases were singleton pregnancies with detailed information of the maternal age, gravidity, parity, maternal height and weight, complications, uterine height and abdominal circumference, results from transabdominal ultrasonography between 32-38 gestational weeks, pregnancy duration, delivery manner, placenta, umbilical cord, and neonatal *** Significant differences were observed in placenta weight and neonatal malformations between the study and control groups. Multivariate analysis revealed increased parity, maternal hyperthyroidism and hyperthyroidism history as risk factors. Fetal abdominal circumferences less than 30 and 32 cm at 32-38 gestational weeks respectively, as determined by ultrasonography, resulted in a Youden index of 0.62. Conclusions SGA infants were associated with a greater risk of smaller placentas and infant malformations. Increased parity, maternal hyperthyroidism, and a hyperthyroid history were risk factors for SGA infants. Fetal abdominal circumference less than 30 cm at 32 gestational weeks and

关键词： small for gestational age singleton pregnancy hyperthyroidism infant malformation

Observation of topological charge transformations in acoustic vortex using passive periodic systems

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 140-147页

作者： Di-Chao Chen Xie liu Changqing Xu Da-Jian Wu Ying Cheng Xiao-jun liu School of Physics and Technology Nanjing Normal University Key Laboratory of Modern Acoustics School of Physics Nanjing University

Vortex transmutation utilizes a periodic system, which not only enables the alteration of the topological charge(TC) of unstable input vortices but also facilitates their transformation into stable structures. This approach is crucial for investigating the characteristics of vortices in various wave systems. Here, we achieve acoustic vortex TC transmutation by employing a welldesigned dual-structured plate external system(DPES). The interactions between the acoustic vortex and the finite-order discrete rotational symmetry lead to the transformation of its topological charge when complete rotational symmetry is broken to Nthorder discrete symmetry. Our results experimentally demonstrate the acoustic vortex TC transmutation based on passive artificial structures, enabling numerous applications in particle manipulation and information multiplexing as well as advancing our understanding and control over free-space acoustic vortices.

关键词： acoustic vortex topological charge transformation artificial structure

Targets capture by distributed active swarms via bio-inspired reinforcement learning

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 210-221页

作者： Kun Xu Yue li jun Sun Shuyuan Du Xinpeng Di Yuguang Yang Bo li Institute of Biomechanics and Medical Engineering Applied Mechanics Laboratory Department of Engineering MechanicsTsinghua University Institute of Nuclear and New Energy Technology Tsinghua University Shanghai Aerospace Control Technology Institute Shanghai Key Laboratory of Aerospace Intelligent Control Technology College of Automation Engineering Nanjing University of Aeronautics and Astronautics

Natural swarms arranged from cells to herds are usually decentralized but display intriguing collective intelligence in coordinating individuals across large scales to efficiently achieve their common goals. Learning from nature may provide new strategies for controlling collective dynamics of synthetic swarms to accomplish specific functions. Here, we present a bioinspired computational framework that steers distributed active swarms to collectively capture and merge targets via reinforcement learning. We exploit collective milling structures of natural herds to cage the targets, and adopt a switching control policy inspired by sperms' chiral dynamics to optimize the trajectories of individuals, through which the active swarms can selforganize to enclose single or multiple distant targets in a dynamical, adaptive and scalable manner. There exists a critical swarm size, beyond which the excessive competition between agents would generate large mechanical forces, leading to capture instability but enabling the transition from short-distance to long-distance merging capture of multiple targets. This work provides physical insights into distributed active swarms and could offer a multilevel, decentralized strategy toward controlling swarm robotics in wide applications such as bio-medical devices, machine immunity, and target clearance.

关键词： swarm intelligence robotics multi-tasks artificial intelligence bionics

Oxidation Resistance of Form-stable Hightemperature Phase Change Thermal Energy Storage Materials Doped by Impregnated Graphite

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 1-12页

作者： li Baorang DAI Jianhuan ZHANG Wei liu Xiangchen YANG liu School of Energy Power and Mechanical Engineering North China Electric Power UniversityBeijing 102206China School of Ener-gy and Environment Southeast UniversityNanjing 210096China

We adopted the solution impregnation route with aluminum dihydrogen phosphate solution as liquid medium for effective surface modification on graphite *** mass ratio of graphite to Al(H_(2)PO_(4))_(3) changed from 0.5:1 to 4:1,and the impregnation time changed from 1 to 7 *** typical composite phase change thermal storage materials doped with the as-treated graphite were fabricated using form-stable *** investigate the oxidation and anti-oxidation behavior of the impregnated graphite at high temperatures,the samples were put into a muffle furnace for a cyclic heat *** on SEM,EDS,DSC techniques,analyses on the impregnated technique suggested an optimized processing conditions of a 3 h impregnation time with the ratio of graphite:Al(H_(2)PO_(4))_(3) as 1:3 for graphite impregnation *** investigations on high-temperature phase change heat storage materials doped by the treated graphite suggested excellent oxidation resistance and thermal cycling performance.

关键词： phase change materials graphite impregnation method oxidation,sintering thermal analysis

Influence of administrative intervention on the availability,utilization, and competency for the use of defibrillators in primary hospitals

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Chinese Medical Journal 2019年第18期132卷 2246-2247页

作者： Jian-liang Zhu Xiao-Lu Sun Jing Lu Jian-jun Zhu Xin-Fa Xu Yu-Bao Xiong li-jun liu Department of Emergency Medicine The Second Affiliated Hospital of Soochow University Suzhou Jiangsu 215004 China Department of Critical Care Medicine Kunshan Hospital of Traditional Chinese Medicine Suzhou Jiangsu 215300 China

To the Editor:Sudden cardiac death is a major public health issue across the world.[1] Timely cardiopulmonary resuscitation (CPR) and defibrillation helps improve prognosis and avert the neurological sequelae of ventricular fibrillation.[2] However,there is low availability and utilization of defibrillators in China.[3] Hence,we investigated the availability and utilization of defibrillators during two consecutive years (before and after an administrative intervention) at all primary (public and private) hospitals in Suzhou city (Jiangsu province,China) to assess the effect of administrative intervention.

关键词： ventricular fibrillation public health administrative intervention

Engineering atomic Rb-N configurations to tune radical pathways for highly selective photocatalytic H2O2 synthesis coupled with biomass valorization

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Journal of Energy Chemistry 2025年第1期100卷 215-225页

作者： Jiaye li Shuang Pan Yihuang Chen Qiong liu College of Chemistry and Materials Engineering Wenzhou University Guangdong Provincial Key Laboratory of Chemical Measurement and Emergency Test Technology (China) Institute of Analysis Guangdong Academy of Sciences (China National Analytical CenterGuangzhou)

Photocatalytic oxygen reduction for hydrogen peroxide （H2O2） synthesis presents a green and costeffective production ***,achieving highly selective H2O2synthesis remains challenging,necessitating precise control over free radical reaction pathways and minimizing undesirable oxidative ***,we report for the visible light-driven simultaneous co-photocatalytic reduction of O2to H2O2and oxidation of biomass using the atomic rubidium-nitride modified carbon nitride（CNRb）.The optimized CNRb catalyst demonstrates a record photoreduction rate of 8.01 mM h-1for H2O2generation and photooxidation rate of 3.75 mM h-1for furfuryl alcohol to furoic acid,achieving a remarkable solar-to-chemical conversion （SCC） efficiency of up to 2.27%.Experimental characterizations and DFT calculation disclosed that the introducing atomic Rb–N configurations allows for the high-selective generation of superoxide radicals while suppressing hydroxyl free radical *** is because the Rb–N serves as the new alternative site to perceive a stronger connection position for O2adsorption and reinforce the capability to extract protons,thereby triggering a high selective redox product *** study holds great potential in precisely regulating reactive radical processes at the atomic level,thereby paving the way for efficient synthesis of H2O2coupled with biomass valorization.

关键词： Free radical reactions

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基于马尔科夫链的长春市乘用车行驶工况构建

吉林大学学报（工学版） 2018年第5期48卷 1366-1373页

作者：曹骞李君刘宇曲大为吉林大学汽车仿真与控制国家重点实验室长春130022

针对乘用车现阶段油耗国标测试结果与实际道路行驶相差较大的问题,研究了长春市乘用车代表性行驶工况。针对长春市乘用车采集一年行驶数据,获得有效数据3 538 335条,应用聚类和马尔科夫链方法构建代表工况,并与上海工况及NEDC工况进行... 详细信息

针对乘用车现阶段油耗国标测试结果与实际道路行驶相差较大的问题,研究了长春市乘用车代表性行驶工况。针对长春市乘用车采集一年行驶数据,获得有效数据3 538 335条,应用聚类和马尔科夫链方法构建代表工况,并与上海工况及NEDC工况进行对比分析。结果表明:构建工况与数据库总体的平均偏差为4.03%,远低于10%的偏差要求,能够准确反映长春市乘用车的行驶特征;长春工况与上海工况及NEDC工况相比差异较大,特征值平均偏差分别为22.7%和21.1%,中国城市行驶工况存在明显差异,现行NEDC工况难以准确描述中国乘用车行驶特征,构建符合国情的行驶工况十分必要。本文结果为提升长春市乘用车测试和评价结果准确性提供了有益参考。

关键词：交通运输规划与管理行驶工况马尔可夫链乘用车

Si-C Foam Porous-Medium Combustion Power-Generation System for Low-Calorific-Value Biomass Syngas

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Journal of Thermal Science 2025年第1期34卷 206-222页

作者： YANG Jianwen CHEN Wei CAO Bingwei liu Xinhui li Hang College of Mechanical and Aerospace Engineering Jilin University School of Mechanical and Vehicle Engineering Changchun University

Syngas produced from the gasification of organic feedstocks from biomass is one of the clean and sustainable sources of *** advantages of simple access and renewability of biomass energy can meet the energy needs of temporary power *** study presents a biomass power-generation system for vehicular *** biomass and a free-piston Stirling engine generator（FPSEG） as the primary material and prime mover,respectively,biomass energy is converted into electricity by combusting the syngas to heat the *** and key parameter design for biomass gasification and thermoelectric conversion systems within a power generation system were performed.A porous medium area was constructed using Si-C foam ceramics to obtain an energy-conversion experimental *** effects of bed height,porosity,porous-region diameter,and air-intake conditions on the power-generation performance were investigated,and optimisations were performed for the thermoelectric conversion *** rate of increase during FPSEG power generation first increased and then decreased with increasing bed height,peaking at a bed height of 40 *** increasing porous-region diameter accelerated FPSEG power generation,whereas porosity changes in the porous media did not significantly affect the rate of change during FPSEG power *** increasing air intake,the rate of increase during power generation first increased and then *** maximum change rate and the highest thermoelectric conversion efficiency of the power-generation system occurred at 9.5 m3/h and 6.5 m3/h（～45.1%）air intakes,*** the thermal inertia and combustion structure of the thermoelectric conversion system significantly increased the power-generation rate of the system,with 1.8 W/s being observed at a 9.7 m3/h air intake.

关键词： biomass combined heat and power (CHP) gasification porous media combustion power generation

Emerging trends in the selective production of value-added aromatics

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Science China Chemistry 2025年第1期68卷 15-20页

作者： Yuchao Wu Houliang Dai Weisheng Yang Yaxing li lichen liu Petrochemical Research Institute Company limited China National Petroleum Corporation Engineering Research Center of Advanced Rare Earth Materials Department of Chemistry Tsinghua University

1 Introduction Aromatics (mainly benzene, toluene, and xylenes, BTX) are essential intermediates in the chemical industry. They are employed in the synthesis of a broad spectrum of chemicals and materials, e.g., various polymers, plastics, resins, solvents, dyes, pharmaceuticals [1]. The manufacturing pathway of BTX mainly includes petroleum reforming of naphtha, coal-to-aromatics, methanol-to-aromatics [2].

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