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World Journal of Pediatrics 2022年第11期18卷 746-752页

作者： Li-Na Zhang Ling cao Ling-Hui meng Department of Pulmonology Children’s HospitalCapital Institute of PediatricsBeijingChina Center for Evidence-Based Medicine Office of Science and TechnologyCapital Institute of PediatricsBeijingChina

Background This study aimed to analyze the pathogenic characteristics of community-acquired pneumonia(CAP)in a children’s hospital before and after the coronavirus disease 2019(COVID-19)pandemic and to provide testimony for preventing CAP in the future.Methods A retrospective analysis was performed.The information was collected from the electronic medical record system of the hospital.A total of 2739 children were included from February 1,2019,to January 31,2021.Results Among these 2739 patients were 1507(55.02%)males and 1232(44.98%)females;the median age was 3.84 years.There were 2364 cases during the pre-COVID-19 period and 375 cases during the post-COVID-19 period.The number of hospitalized children after the pandemic was 84.14%lower.The median age after the onset was 1.5 years younger than that before the onset(4.08 years old)(Z=−7.885,Pbacteria(50.42%)>viruses(29.57%)>fungi(3.43%).During the post-COVID-19 period,the pathogen proportions were bacteria(56.53%)>viruses(53.60%)>MP(23.47%)>fungi(3.73%).Conclusions There was a significant decrease in the number of children with CAP hospitalized after the pandemic,especially among school-age children,and the pathogen proportions of CAP with MP and IV were significantly decreased.We inferred that CAP was effectively prevented in school-age children because of the strong mitigation measures.

关键词： Community-acquired pneumonia Comparison Coronavirus disease 2019 Pathogen

Feature Relationships Learning Incorporated Age Estimation Assisted by Cumulative Attribute Encoding

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Computers, Materials & Continua 2018年第9期56卷 467-482页

作者： Qing Tian Meng Cao Tinghuai Ma School of Computer and Software Nanjing University of Information Science and TechnologyNanjing210044China Jiangsu Engineering Center of Network Monitoring Nanjing University of Information Science and TechnologyNanjing210044China School of Electrical and Electronic Engineering University of ManchesterManchesterM139PLUK

The research of human facial age estimation(AE)has attracted increasing attention for its wide applications.Up to date,a number of models have been constructed or employed to perform AE.Although the goal of AE can be achieved by either classification or regression,the latter based methods generally yield more promising results because the continuity and gradualness of human aging can naturally be preserved in age regression.However,the neighbor-similarity and ordinality of age labels are not taken into account yet.To overcome this issue,the cumulative attribute(CA)coding was introduced.Although such age label relationships can be parameterized via CA coding,the potential relationships behind age features are not incorporated to estimate age.To this end,in this paper we propose to perform AE by encoding the potential age feature relationships with CA coding via an implicit modeling strategy.Besides that,we further extend our model to gender-aware AE by taking into account gender variance in aging process.Finally,we experimentally validate the superiority of the proposed methodology.

关键词： Age estimation cumulative attribute gender-aware age estimation correlation relationship learning

L_(1)-Smooth SVM with Distributed Adaptive Proximal Stochastic Gradient Descent with Momentum for Fast Brain Tumor Detection

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Computers, Materials & Continua 2024年第5期79卷 1975-1994页

作者： Chuandong Qin Yu cao Liqun meng School of Mathematics and Information Science North Minzu UniversityYinchuan750021China Ningxia Key Laboratory of Intelligent Information and Big Data Processing Yinchuan750021China

Brain tumors come in various types,each with distinct characteristics and treatment approaches,making manual detection a time-consuming and potentially ambiguous process.Brain tumor detection is a valuable tool for gaining a deeper understanding of tumors and improving treatment outcomes.Machine learning models have become key players in automating brain tumor detection.Gradient descent methods are the mainstream algorithms for solving machine learning models.In this paper,we propose a novel distributed proximal stochastic gradient descent approach to solve the L_(1)-Smooth Support Vector Machine(SVM)classifier for brain tumor detection.Firstly,the smooth hinge loss is introduced to be used as the loss function of SVM.It avoids the issue of nondifferentiability at the zero point encountered by the traditional hinge loss function during gradient descent optimization.Secondly,the L_(1) regularization method is employed to sparsify features and enhance the robustness of the model.Finally,adaptive proximal stochastic gradient descent(PGD)with momentum,and distributed adaptive PGDwithmomentum(DPGD)are proposed and applied to the L_(1)-Smooth SVM.Distributed computing is crucial in large-scale data analysis,with its value manifested in extending algorithms to distributed clusters,thus enabling more efficient processing ofmassive amounts of data.The DPGD algorithm leverages Spark,enabling full utilization of the computer’s multi-core resources.Due to its sparsity induced by L_(1) regularization on parameters,it exhibits significantly accelerated convergence speed.From the perspective of loss reduction,DPGD converges faster than PGD.The experimental results show that adaptive PGD withmomentumand its variants have achieved cutting-edge accuracy and efficiency in brain tumor detection.Frompre-trained models,both the PGD andDPGD outperform other models,boasting an accuracy of 95.21%.

关键词： Support vector machine proximal stochastic gradient descent brain tumor detection distributed computing

China-Australia Relationship: Australian Public Opinion on China

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学术界 2020年第1期 198-208页

作者： cao meng School of Government Peking University

The latest released Lowy Poll 2019 shows Australia’s public opinion towards China has some negative shifts again.What does this mean for yet-to-be-repaired China-Australia relationship?Does Australian public opinion have an impact on its foreign policy?This article took an analysis of this issue.We found public opinion does have an influence on Australia’s China policy formation through influencing the“popular narrative”on China issue.Nevertheless,the economic ties with China are still fundamental.In the field of foreign policy,the government has a relatively high degree of freedom for direction leading.These facts make the prospect of China-Australia relationship more dependent on the will of current government.While taking care of public opinion is always a first task for them.

关键词： China-Australia relationship public opinion foreign policy security narrative

On-off-on fluorescence detection for biomolecules by a fluorescent cage through host-guest complexation in water

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Chinese Chemical Letters 2022年第5期33卷 2459-2463页

作者： Honghong Duan Fan cao Minjie Zhang meng Gao Liping cao College of Chemistry and Materials Science Northwest UniversityXi’an 710069China National Engineering Research Center for Tissue Restoration and Reconstruction Key Laboratory of Biomedical Engineering of Guangdong ProvinceKey Laboratory of Biomedical Materials and Engineering of the Ministry of EducationInnovation Center for Tissue Restoration and ReconstructionSouth China University of TechnologyGuangzhou 510006China

Detection of nucleoside derivatives has paramount importance because they are the essential biomolec-ular units for all life.Herein,we report a host-guest approach by using a fluorescent tetraphenylethene-based octacationic cage as host and 8-hydroxypyrene-1,3,6-trisulfonic acid trisodium salt(HPTS)as guest and fluorescent indicator to form non-fluorescent 1:1:1 host-(endo-exo)guest complex in water.This new host-(endo-exo)guest complex can be successfully used for detecting nucleosides(e.g.,ATP and GTP),DNA(e.g.,sm-DNA),and antibiotics(e.g.,Penicillin G)with off-on fluorescence response via a competitive host-guest exchange with HPTS as exo-guest in water.Furthermore,this on-off-on fluorescent host-guest com-plex is also used for cell imaging based on ATP concentration in HeLa cells.Therefore,this study not only provides insight into the construction of a supramolecular probe with on-off-on fluorescence via host-guest complexation and exchange in solution,but also realizes a universal method for detecting and monitoring biomolecules.

关键词： Host-guest complexation Tetraphenylethene-based octacationic cage Nucleoside derivatives Fluorescence Cell imaging

Effect of Active–Passive Deformation on the Thrust by the Pectoral Fins of Bionic Manta Robot

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Journal of Bionic Engineering 2024年第2期21卷 718-728页

作者： Yang Lu Shaomin meng Cheng Xing Yiwei Hao Yonghui cao Guang Pan Yong cao School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an710072China Unmanned Vehicle Innovation Center Ningbo Institute of NPUNingbo315103China State Key Lab of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou310027China Zhejiang Key Laboratory of Advanced Manufacturing Technology School of Mechanical EngineeringZhejiang UniversityHangzhou310027China

Bionic manta underwater vehicles will play an essential role in future oceans and can perform tasks,such as long-duration reconnaissance and exploration,due to their efficient propulsion.The manta wings’deformation is evident during the swimming process.To improve the propulsion performance of the unmanned submersible,the study of the deformation into the bionic pectoral fin is necessary.In this research,we designed and fabricated a flexible bionic pectoral fin,which is based on the Fin Ray®effect with active and passive deformation(APD)capability.The APD fin was actively controlled by two servo motors and could be passively deformed to variable degrees.The APD fin was moved at 0.5 Hz beat frequency,and the propulsive performance was experimentally verified of the bionic pectoral fins equipped with different extents of deformation.These results showed that the pectoral fin with active–passive deformed capabilities could achieve similar natural biological deformation in the wingspan direction.The average thrust(T)under the optimal wingspan deformation is 61.5%higher than the traditional passive deformed pectoral fins.The obtained results shed light on the design and optimization of the bionic pectoral fins to improve the propulsive performance of unmanned underwater vehicles(UUV).

关键词： Manta ray Bionic pectoral fin Fin Ray®effect Active-passive deformation(APD)

Low temperature one-pot synthesis of 1,1-diethoxyethane from ethanol on Bi/BiCeO_(x)with strong metal-support interactions

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Nano Research 2023年第3期16卷 3709-3718页

作者： Zhe An Jiayu Liu Meng Cao Jian Zhang Yanru Zhu Hongyan Song Xu Xiang Jing He State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China

The direct conversion of ethanol to 1,1-diethoxyethane(DEE)through one-pot dehydrogenation-acetalization has attracted broad interest from both academia and industry.Based on thermodynamics,the oxidative dehydrogenation of alcohol to acetaldehyde requires high temperature to activate oxygen to realize the C-H cleavage,while the acetalization of acetaldehyde with ethanol is exothermic reversible reaction favorable at low temperature.The mismatching of the reaction condition for the two consecutive steps makes it a great challenge to achieve both high ethanol conversion and high DEE selectivity.This work reports a highly efficient bi-functional catalysis by Bi/BiCeO_(x)for one-pot oxidative dehydrogenation-acetalization route from ethanol to DEE under 150℃and ambient pressure,affording a selectivity of 98.5%±0.5%to DEE at an ethanol conversion of 87.0%±1.0%.An efficient tandem catalysis has been achieved on the interfacial Bi^(δ)+-Ov-Ce^(III)sites in Bi/BiCeO_(x)established by strong metal-support interaction,in which Biδ+-Ov-sites contribute to the oxidative dehydrogenation of ethanol at mild temperature,and-Ov-CeIII sites to the subsequent acetalization between the generated acetaldehyde and ethanol.

关键词： ethanol conversion 1 1-diethoxyethane strong metal-support interaction Biδ+-Ov-CeIII sites

Atomic Layer Deposition of High-Capacity Anodes for Next-Generation Lithium-Ion Batteries and Beyond

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Energy & Environmental Materials 2021年第3期4卷 363-391页

作者： Yanqiang cao Xiangbo meng Aidong Li Institute of Micro-nano Photonic&Beam Steering School of ScienceNanjing University of Science and TechnologyNanjing 210094China Department of Mechanical Engineering Center for Advanced Surface EngineeringUniversity of ArkansasFayetteville AR 72701USA Materials Science and Engineering Department National Laboratory of Solid State MicrostructuresCollege of Engineering and Applied SciencesCollaborative Innovation Center of Advanced MicrostructuresJiangsu Key Laboratory of Artificial Functional MaterialsNanjing UniversityNanjing 210093China

Electrification has great impacts on our modern society.To electrify future transportation,state-of-the-art lithium-ion batteries(LIBs)are still not sufficient in multiple aspects including cost,energy density,lifespan,and safety.To this end,next-generation high-energy LIBs and beyond are highly regarded.In this regard,high-capacity anodes are undergoing intensive investigation,such as silicon,SnO_(2),and lithium metal.However,such anode materials are commonly experiencing large volume changes and related issues,which are reflected on mechanical degradation,capacity fading,low efficiency,and unsatisfactory lifetime.To address these challenges,many technical strategies have been investigated.In the past decade,atomic layer deposition(ALD)has emerged as a new promising technique enabling atomic-scale surface modification and nanoscale design of high-capacity anodes for high performance.In this review,recent ALD studies on developing high-capacity anodes for LIBs and beyond are thoroughly summarized.In addition,ALD strategies and their effectiveness in pursing high-energy LIBs and beyond are discussed.Particularly,we highlighted the latest advances of ALD for addressing the notorious issues associated with Li metal anodes.It is expected that this work will promote the applications of ALD in new battery systems.

关键词： atomic layer deposition high-capacity anodes lithium-ion batteries and beyond nanostructured electrodes surface coating

High-resolution simulation of upper-ocean submesoscale variability in the South China Sea:Spatial and seasonal dynamical regimes

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Acta Oceanologica Sinica 2022年第7期41卷 26-41页

作者： Haijin cao Xin meng Zhiyou Jing Xiaoxiao Yang Key Laboratory of Marine Hazards Forecasting of Ministry of Natural Resources Hohai UniversityNanjing210024China College of Oceanography Hohai UniversityNanjing210024China State Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou510301China

Submesoscale processes in marginal seas usually have complex generating mechanisms,highly dependent on the local background flow and forcing.This numerical study investigates the spatial and seasonal differences of submesoscale activities in the upper ocean of the South China Sea(SCS)and the different dynamical regimes for sub-regions.The spatial and seasonal variations of vertical vorticity,horizontal convergence,lateral buoyancy gradient,and strain rate are analyzed to compare the submesoscale phenomenon within four sub-regions,the northern region near the Luzon Strait(R1),the middle ocean basin(R2),the western SCS(R3),and the southern SCS(R4).The results suggest that the SCS submesoscale processes are highly heterogeneous in space,with different seasonalities in each sub-region.The submesoscale activities in the northern sub-regions(R1,R2)are active in winter but weak in summer,while there appears an almost seasonal anti-phase in the western region(R3)compared to R1 and R2.Interestingly,no clear seasonality of submesoscale features is shown in the southern region(R4).Further analysis of Ertel potential vorticity reveals different generating mechanisms of submesoscale processes in different sub-regions.Correlation analyses also show the vertical extent of vertical velocity and the role of monsoon in generating submesoscale activities in the upper ocean of sub-regions.All these results suggest that the sub-regions have different regimes for submesoscale processes,e.g.,Kuroshio intrusion(R1),monsoon modulation(R2),frontal effects(R3),topography wakes(R4).

关键词： submesoscale South China Sea high-resolution simulation spatial difference seasonal difference

Strategies and prospects for melatonin to alleviate abiotic stress in horticultural plants

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Horticultural Plant Journal 2024年第3期10卷 601-614页

作者： Xiaoyun Wang Meng Cao Hongxin Li Ying Liu Shuangxi Fan Na Zhang Yangdong Guo College of Horticulture China Agricultural UniversityBeijing100193China College of Plant Science and Technology Beijing University of AgricultureBeijing102206China Beijing Bei Nong Enterprise Management Co. Ltd.Beijing102206China Sanya Institute of China Agricultural University SanyaHainan572000China

Melatonin is a conserved pleiotropic molecule in animals and plants.Melatonin is involved in many development processes and stress responses;thus,exploring its function in plants,particularly in horticultural plants,has become a rapidly developing field.Many studies have revealed that phytomelatonin acts as a plant biostimulant and increase its tolerance to various abiotic stressors,including extreme temperature,drought,osmotic disturbance,heavy metals,and ultraviolet(UV).Melatonin appears to have roles in the scavenging of reactive oxygen species(ROS)and other free radicals,affecting the primary and secondary metabolism of plants,regulating the transcripts of stress-related enzymes and transcription factors,and crosstalk with other hormones under different environmental conditions.This pleiotropy makes phytomelatonin an attractive regulator to improve resistance to abiotic stress in plants.The recent discovery of the potential phytomelatonin receptor CAND2/PMTR1 and the proposition of putative models related to the phytomelatonin signaling pathways makes phytomelatonin a new plant hormone.Based on relevant studies from our laboratory,this review summarizes the phytomelatonin biosynthetic and metabolic pathways in plants and the latest research progress on phytomelatonin in abiotic stress of horticultural plants.This study will provide a reference for elucidating the regulatory mechanism of phytomelatonin affecting the resistance to abiotic stress in plants.

关键词： Abiotic stress Biostimulant Horticultural plants Phytomelatonin