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Factors of Fetal Origin in the Regulation of Labor Initiation and Preterm Birth

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Maternal-Fetal Medicine 2023年第4期5卷 238-243页

作者： Longkun ding Lu gao Department of Physiology Naval Medical UniversityShanghai 200433China Shanghai Key Laboratory for Assisted Reproduction and Reproductive Genetics Shanghai 200135China

Preterm birth is the leading cause of mortality and morbidity in newborns and children under 5 years-of-age.In order to improve the survival rate and quality of preterm infants,there is critical need to identify the specific mechanisms underlying the initiation of labor.Pregnancy represents a period of constant interactive dialog between mother and fetus.A disturbance in the pattern of maternal-fetal communication can induce physiological or pathological labor.Although a number of studies have investigated the contributions of maternal factors to the initiation of labor,the concept that fetal organ development and maternal adaptation are coordinated has emerged over recent years,thus emphasizing that factors of fetal origin may serve as hormonal signals for the initiation of labor.In this review,we summarize and discuss several specific mechanisms by which factors of fetal origin may influence parturition during term or preterm labor,including the specific regulation of fetal organs,including the lungs and accessory organs during pregnancy.Future research may focus on the specific pathways by which signals from the fetal lungs and other fetal organs interact with the maternal system to initiate eventual labor.

关键词： Premature birth Fetal origin factor Placenta Fetal membrane Parturition Term labor

Case study of post uplift in deep excavation of a subway station in thick soft clay using long pile foundations

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Underground Space 2022年第2期7卷 254-267页

作者： Yanbin gao Zhouxiang ding Department of Geotechnical Engineering Tongji University#1239 Siping RoadShanghai 200092China Department of Mechanical Engineering University of SaskatchewanCanada

There is growing engineering concern about the base heave and post uplift phenomena in deep excavation in soft clay,which may pose a risk of instability of retaining systems.The purpose here is to conduct a detailed case study on the post uplift observed in a 17.6-meterdeep braced excavation of a subway station in thick soft clay(total thickness up to 42 m)in Shanghai.In this case,a large uplift up to 87 mm unexpectedly developed for the post founded on a 30-meter-long pile foundation.Efforts were first made to examine the complex relationships between the post uplift with the excavation depth(H),Terzaghi’s safety factor against base heave(Fs)and maximum deflection of retaining wall.A simplified approach for soil-post-strut interaction analysis was then proposed and used for quantitative research.The working characteristics of the long pile foundation under low safety factor against base heave(Fs<1.5)are summarized as following:(a)the back-analyzed neutral plane,where soil uplift equals the post uplift,lies at approximately 0.68 times the pile length from the pile top;(b)deep soil movement below the neutral plane results in the observed post uplift;(c)strut reaction plays a minor role in the restriction of post uplift.The influence of base treatment and excavation/construction procedures on post uplift and the principles of pile foundation design are also discussed in this paper.

关键词： Post uplift Deep excavation Field observations Neutral plane Soft clay Pile foundation

A Blockchain-Based Life-Cycle Environmental Management Framework for Hospitals in the COVID-19 Context

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Engineering 2023年第1期20卷 208-221页

作者： Botao Zhong Han gao Lieyun ding Yuhang Wang National Center of Technology Innovation for Digital Construction Huazhong University of Science and TechnologyWuhan 430074China School of Civil and Hydraulic Engineering Huazhong University of Science and TechnologyWuhan 430074China Department of Civil and Building Systems Technische Universität BerlinBerlin 13156Germany

During the coronavirus disease 2019 (COVID-19) emergency, many hospitals were built or renovated around the world to meet the challenges posed by the rising number of infected cases. Environmental management in the hospital life cycle is vital in preventing nosocomial infection and includes many infection control procedures. In certain urgent situations, a hospital must be completed quickly, and work process approval and supervision must therefore be accelerated. Thus, many works cannot be checked in detail. This results in a lack of work liability control and increases the difficulty of ensuring the fulfillment of key infection prevention measures. This study investigates how blockchain technology can transform the work quality inspection workflow to assist in nosocomial infection control under a fast delivery requirement. A blockchain-based life-cycle environmental management framework is proposed to track the fulfillment of crucial infection control measures in the design, construction, and operation stages of hospitals. The proposed framework allows for work quality checking after the work is completed, when some work cannot be checked on time. Illustrative use cases are selected to demonstrate the capabilities of the developed solution. This study provides new insights into applying blockchain technology to address the challenge of environmental management brought by rapid delivery requirements.

关键词： Blockchain Envir onmental management Nosocomial infection control Work quality management Life-cycle traceability

Advances in photothermal conversion of carbon dioxide to solar fuels

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能源化学:英文版 2023年第8期83卷 62-78,I0004页

作者： Wa gao Yinwen Li Dequan Xiao ding Ma College of Bioscience and Resources Environment Beijing University of AgricultureBeijing 102206China College of Chemistry and Molecular Engineering and College of Engineering Peking UniversityBeijing 100871China Center for Integrative Materials Discovery Department of Chemistry and Chemical and Biomedical EngineeringUniversity of New HavenWest HavenCT 06516USA

Converting carbon dioxide(CO_(2)) into useful fuels or chemical feedstocks is important for achieving peak carbon emission and carbon neutrality.Recently,photothermal catalysis has been extensively studied and applied due to its advantages over traditional heat-driven catalysis.In this review,we focus on photothermal catalysis of thermodynamically uphill reactions that convert CO_(2)into value-added products.We first introduce the fundamentals of photothermal catalysis for CO_(2)reduction,including the definition and classification of photothermal catalysis,followed by their photothermal conversion processes.The structure design of different types of photothermal catalysts is summarized.The superior performance of photothermal catalytic conversion of CO_(2)is illustrated and discussed,including improved CO_(2)activation,tunable selectivity towards different solar fuel products,and resistance to sintering and coking.Finally,the perspectives and challenges in this cutting-edge field are presented with the aim of advancing understanding of the underlying mechanisms and inspiring rational design of photothermal catalysts for highly efficient solar-to-fuel conversion.

关键词： Solarenergy Photothermal catalysis CO_(2)reduction Catalyst design Performance improvement

Fabrication of fire-retardant building materials via a hyper-crosslinking chemical conversion process from waste polystyrenes

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Energy and Built Environment

Energy and Built Environment 2022年第2期3卷 226-232页

作者： Changhui Liu Yuanhui Xie Ding Gao Xiancong Shi Zhonghao Rao School of Electrical and Power Engineering China University of Mining and TechnologyXuzhou 221116China

Polystyrene(PS)is rich in plastic materials,but it produces a large amount of waste every year,causing a huge burden on the environment.Although PS plastic is the source of a common"white pollution"in daily life,it still has a high utilization value.At the same time,the flammability of PS material determines that it cannot be applicated in places where fire accidents occur frequently.As a result,its application has been greatly limited.In order to realize the efficient utilization of waste PS and broaden its scope of application,PS was modified by hyper-crosslinking in order to improve its fire-retardant performance.In this method,the PS solution with high purity was obtained by dissolving waste PS foam with 1,2-dichloroethane(DCE),and then the hyper-crosslinked polymer with high specific surface area was prepared by adding cross-linking agent formaldehyde dimethyl acetal(FDA)and a Lewis-acid catalyst ferric chloride(FeCl_(3)).Further studies showed that the effects of the amount of cross-linking agent FDA,catalyst FeCl_(3) and PS on the reaction products were different.In addition,compared the as-prepared fire-retardant materials with PS foam from the aspects of flame retardancy and thermal insulation,it can be concluded that the fire-retardant performance of the materials prepared by this method has been significantly enhanced.And it is proved that this method is feasible towards the preparation of a large number of fire-retardant composite materials by using a scale-up experiment.

关键词： Waste polystyrene Building materials Fire-retardant Hyper-crosslinking High-value added utilization

Advances in Mn‑Based Electrode Materials for Aqueous Sodium‑Ion Batteries

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纳微快报:英文版 2023年第11期15卷 19-60页

作者： Changsheng ding Zhang Chen Chuanxiang Cao Yu Liu Yanfeng gao School of Materials Science and Engineering Shanghai UniversityShanghai 200444People’s Republic of China Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 200050People’s Republic of China Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources Qinghai Institute of Salt LakesChinese Academy of SciencesXining 81000People’s Republic of China

Aqueous sodium-ion batteries have attracted extensive attention for large-scale energy storage applications,due to abundant sodium resources,low cost,intrinsic safety of aqueous electrolytes and eco-friendliness.The electrochemical performance of aqueous sodium-ion batteries is affected by the properties of electrode materials and electrolytes.Among various electrode materials,Mn-based electrode materials have attracted tremendous attention because of the abundance of Mn,low cost,nontoxicity,eco-friendliness and interesting electrochemical performance.Aqueous electrolytes having narrow electrochemical window also affect the electrochemical performance of Mn-based electrode materials.In this review,we introduce systematically Mn-based electrode materials for aqueous sodium-ion batteries from cathode and anode materials and offer a comprehensive overview about their recent development.These Mn-based materials include oxides,Prussian blue analogues and polyanion compounds.We summarize and discuss the composition,crystal structure,morphology and electrochemical properties of Mn-based electrode materials.The improvement methods based on electrolyte optimization,element doping or substitution,optimization of morphology and carbon modification are highlighted.The perspectives of Mn-based electrode materials for future studies are also provided.We believe this review is important and helpful to explore and apply Mn-based electrode materials in aqueous sodium-ion batteries.

关键词： Sodium-ion batteries Aqueous electrolytes Mn-based electrode materials Electrochemical performance Improvement methods

An evaluation of COVID-19 in Italy:A data-driven modeling analysis

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Infectious Disease Modelling 2020年第1期5卷 495-501页

作者： Yongmei ding Liyuan gao College of Science Wuhan University of Science and TechnologyHuangjiahu West Road430065WuhanChina

The novel coronavirus(COVID-19)that has been spreading worldwide since December 2019 has sickened millions of people,lock down major cities and some countries,prompted unprecedented global travel restrictions.Real data-driven modeling is an effort to help evaluate and curb the spread of the novel virus.Lockdowns and the effectiveness of reduction in the contacts in Italy has been measured via our modified model,with the addition of auxiliary and state variables that represent,contacts with infected,conversion rate and latent propagation.Results show the decrease in infected people due to stay-athome orders and tracing quarantine intervention.The effect of quarantine and centralized medical treatment was also measured through numerical modeling analysis.

关键词： COVID-19 Italy Modified SEIR

Feasibility of LTE-Based GEO Satellite Mobile Communication Systems to Support VoIP for Handheld Terminals

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Chinese Journal of Electronics 2019年第4期28卷 829-834页

作者： ding Dan gao Zhen CHENG Naiping Department of Electronic and Optical Engineering Space Engineering University School of Electrical and Information Engineering Tianjin University

To facilitate the integration of terrestrial and satellite mobile communication systems in the future,the new generation of satellite mobile communication system should be Long-term evolution(LTE)-based.In LTE, voice is carried by Internet protocol(IP)packets(voice over IP, VoIP). The feasibility of LTEbased Geosynchronous earth orbit(GEO) satellite mobile communication systems for Vo IP is discussed. Detailed link budgets are created for typical handheld terminals.The effectiveness of Physical resource block(PRB)bundling and Transmission time interval(TTI) bundling for the capacity improvement of downlink and uplink are evaluated, and further uplink improvement for low level terminals by Narrowband resource block(NRB)scheme is also studied. The analysis results show that the downlink VoIP transmission is mainly power limited, and optimization of PRB or TTI bundling can maximize the capacity. For uplink, only highlevel terminals can support VoIP under the normal LTE frame structure, and TTI bundling and Resource block(RB) block techniques can help the low-level terminals support VoIP transmission.

关键词： Satellite mobile communications Geosynchronous earth orbit(GEO) Long-term evolution(LTE) Voice over internet protocol(VoIP) Handheld terminals

Tuning the near room temperature oxidation behavior of highentropy alloy nanoparticles

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Nano Research 2022年第4期15卷 3569-3574页

作者： Jing gao Jun ding Yin Zhang Ting Zhu Qian Yu Center of Electron Microscopy and State Key Laboratory of Silicon Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China Center for Alloy Innovation and Design State Key Laboratory for Mechanical Behavior of MaterialsXi'an Jiaotong UniversityXi'an 710049China Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

Understanding the oxidation behavior of high-entropy alloys(HEAs)is essential to their practical applications.Here we conducted in situ environmental transmission electron microscopy(E-TEM)observations of dynamic oxidation processes in CrMnFeCoNi and CrFeCoNiPd nanoparticles(NPs)near room temperature.During the oxidation of CrMnFeCoNi NPs,a favorable oxidation product was MnCr_(2)O_(4)with the spinel structure.The surface nanoislands of MnCr_(2)O_(4)underwent dynamic reconstruction,resulting in the thickened oxide layer with less crystallinity.In CrFeCoNiPd NPs,the reactive element Mn was replaced by the inert element Pd.As a result,a favorable oxide product was CrO_(2)with the rutile structure.CrO_(2)formed on the NP surface and was a result of Cr outward diffusion through the oxide layer.In addition,FeO nanocrystals formed at the oxide/metal interface and were a result of O inward diffusion through the oxide layer.We also performed first principles calculations to provide insights into the energetics and diffusion rates related to oxide formation.These results reveal the non-equilibrium processes of oxidation in HEA NPs that can be strongly influenced by small particle sizes and large surface areas.This work underscores the high tunability of oxidation behavior in nanoscale HEAs by changing their constituent alloying elements.

关键词： In situ transmission electron microscopy(TEM) high-entropy alloy(HEA)nanoparticles(NPs) oxidation