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World Journal of Pediatrics 2024年第4期20卷 404-412页

作者： Xin‑Nan Zong hui Li Ya‑{1. Zhang Department of Growth and Development Capital Institute of PediatricsBeijing 100020China

Background A more comprehensive assessment of growth and nutrition in children is required in China due to rapid socioeconomic *** aimed to investigate height and body mass index(BMI)trajectories from 1.75 to 201. and the prevalence of stunting and obesity in 201. among children in Chinese *** A total of 904,263 children from birth to 6.9 years were collected from a series of nationally representative surveys in *** and BMI trajectories and prevalence of stunting,underweight,overweight and obesity were *** The average height level of Chinese urban children under 7 years presented a positive secular trend from 1.75 to 201.;however,a slowing tendency occurred in 2005‒*** apparent increase was observed at the 5th,50th and 95th percentiles of BMI in urban children aged 3 years and older,with a more prominent increase at the 95th *** total prevalence of stunting and underweight under 7 years was 1.4%and 2.0%,*** total prevalence of overweight and obesity under 7 years was 1..6%and 4.3%,respectively,with 1..7%and 4.9%for boys,1..6%and 3.6%for girls,1..1.and 4.0%in urban areas and 1..1.and 4.5%in suburban rural *** The average height level of Chinese urban children has reached World Health Organization child growth standards since 2005 and presented a slowing tendency in secular trend in 2005‒*** attention and efforts and public health interventions should be urgently made to combat overweight and obesity among preschool children.

关键词： Body mass index Children Height Obesity Stunting

Associative Tasks Computing Offloading Scheme in Internet of Medical Things with Deep Reinforcement Learning

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China Communications 2024年第4期21卷 38-52页

作者： Jiang Fan qin Junwei Liu Lei Tian {1. School of Communications and Information Engineering Xi’an University of Posts and TelecommunicationsXi’an 710121China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China

The Internet of Medical Things(Io MT) is regarded as a critical technology for intelligent healthcare in the foreseeable 6G era. Nevertheless, due to the limited computing power capability of edge devices and task-related coupling relationships, Io MT faces unprecedented challenges. Considering the associative connections among tasks, this paper proposes a computing offloading policy for multiple-user devices(UDs) considering device-to-device(D2D) communication and a multi-access edge computing(MEC)technique under the scenario of Io MT. Specifically,to minimize the total delay and energy consumption concerning the requirement of Io MT, we first analyze and model the detailed local execution, MEC execution, D2D execution, and associated tasks offloading exchange model. Consequently, the associated tasks’ offloading scheme of multi-UDs is formulated as a mixed-integer nonconvex optimization problem. Considering the advantages of deep reinforcement learning(DRL) in processing tasks related to coupling relationships, a Double DQN based associative tasks computing offloading(DDATO) algorithm is then proposed to obtain the optimal solution, which can make the best offloading decision under the condition that tasks of UDs are associative. Furthermore, to reduce the complexity of the DDATO algorithm, the cacheaided procedure is intentionally introduced before the data training process. This avoids redundant offloading and computing procedures concerning tasks that previously have already been cached by other UDs. In addition, we use a dynamic ε-greedy strategy in the action selection section of the algorithm, thus preventing the algorithm from falling into a locally optimal solution. Simulation results demonstrate that compared with other existing methods for associative task models concerning different structures in the Io MT network, the proposed algorithm can lower the total cost more effectively and efficiently while also providing a tradeoff between delay and energy co

关键词： associative tasks cache-aided procedure double deep Q-network Internet of Medical Things(IoMT) multi-access edge computing(MEC)

Regulation of solvation structure and the cooperation environment of potassium bonds for wider-temperature adaptive potassium storage

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Rare Metals 2024年第4期43卷 1610-1621页

作者： Bing-Bing Liu Yi-hui Liu You-Bin Zhang Zhen-Guo Qi Guo-hui qin State Key Laboratory Base for Eco-Chemical Engineering College of Chemical EngineeringQingdao University of Science and TechnologyQingdao266042China Shandong Synergetic Innovation Center of Ecological and Chemical Engineering Qingdao266042China

Antimony selenide(Sb_(2)Se_(3))is one of the perspective candidates for potassium-ion batteries due to its advanced virtues stem including featured high capacity,fertile reserves and the relative narrow band *** the unique advantages,it is still plagued by the unstable interface compatibility and poor wider-temperature *** optimization of microstructure and the construction of inorganic-organic hybrids with a low desolvation barrier and rapid kinetics behaviors are efficient to address these *** Sb_(2)Se_(3)nanorods enclosed by the S-doped carbon layer(SC),further crosslinked by the poly(N-isopropylacrylamide)(PM)film(PM@Sb_(2)Se_(3)@SC),were artificially fabricated,and it displays the enrichment ion aggregated model as well as contacted ion pair state,the well-tailored cooperation environment of potassium bonds,assuring a homogeneous potassium deposition and an excellent widertemperature *** complicated experimental studies and theoretical calculations authenticate the synergistic effects of geometric conformation and compositional design for the tremendously enhanced potassium ***,the full device over PM@Sb_(2)Se_(3)@SC anode and the potassium Prussian blue cathode manifests impressively durable cycling life and wider-temperature adaptability,verifying the glorious contribution from the finely manipulation in solvation structure and potassium bonds to enhancing the potassium storage behaviors.

关键词： Anode Sb_(2)Se_(3) rods Interface compatibility Inorganic-organic electrode Potassium ion battery

Ligand-controlled electrochemiluminescence generation from CdSe/CdS/ZnS core/shell/shell quantum dots

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Nano Research 2024年第8期17卷 7776-7785页

作者： hui Sun Zhiyuan Cao Haiyan {1. Xiaogang Peng Bin Su Key Laboratory of Excited-State Materials of Zhejiang Province Department of ChemistryZhejiang UniversityHangzhou 310058China

The CdSe/CdS/ZnS core/shell/shell quantum dots(QDs)with strong exciton confinement have manifested themselves as competitive light-emitting materials in electrochemiluminescence(ECL).However,cathodic ECL generation by these QDs requires the injection of electron and hole from solid electrode and electrogenerated radicals(for example SO_(4)•^(−)),which is inevitably influenced by not only the inorganic structure of QDs but also the organic ligands on the *** this work we aimed at studying the impact of surface organic ligands on ECL performance of CdSe/CdS/ZnS *** changing the surface ligand from oleate to acetate,we phenomenologically observed the positive shift of ECL onset potential by ca.200 mV and the increase of ECL intensity by~1.0 times,suggesting that a short ligand is more favorable for ECL *** further comprehend the ligand effect,we measured the charge injection kinetics using potential-modulated,time-resolved photoluminescence,and thinlayer spectroelectrochemistry *** electron and hole injection into QDs were found to be accelerated by 2–20 times if shortening the ligand from oleate to acetate,confirming the significant impact of surface ligands on ECL performance of *** study is expected to provide guidance on how to design surface functionalized QDs for specific applications such as ECL immunodiagnosis,photocatalysis,and photovoltaics.

关键词： electrochemiluminescence quantum dots spectroelectrochemistry surface ligands charge injection charge transfer

Resolution Enhancement of SOHO/MDI Magnetograms

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Research in Astronomy and Astrophysics 2024年第6期24卷 358-367页

作者： Ying qin Kai-Fan Ji {1. Liu Xiao-Guang Yu Yunnan Observatories Chinese Academy of SciencesKunming 650011China University of Chinese Academy of Sciences Beijing 100049China Yunnan Key Laboratory of Solar Physics and Space Science Kunming 650216China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China

Research on the solar magnetic field and its effects on solar dynamo mechanisms and space weather events has benefited from the continual improvements in instrument resolution and measurement *** augmentation and assimilation of historical observational data timelines also play a significant role in understanding the patterns of solar magnetic field *** the realm of astronomical data processing,super-resolution(SR)reconstruction refers to the process of using a substantial corpus of training data to learn the nonlinear mapping between low-resolution(LR)and high-resolution(HR)images,thereby achieving higherresolution astronomical *** paper is an application study in high-dimensional nonlinear *** learning models were employed to perform SR modeling on SOHO/MDI magnetograms and SDO/HMI magnetograms,thus reliably achieving resolution enhancement of full-disk SOHO/MDI magnetograms and enhancing the image resolution to obtain more detailed *** this study,a data set comprising 971.pairs of data from 201. April to 201. February was used as the training set,1.32 pairs from 201. March were used as the validation set and 1.34 pairs from 201. April were used as the test *** data preprocessing,we randomly cropped 1.8×1.8 sub-images as the LR cases from the full-disk MDI magnetograms,and the corresponding 51.×51. sub-images as HR ones from the HMI full-disk magnetograms for model *** tests conducted have shown that the study successfully produced reliable 4×SR reconstruction of full-disk MDI *** MESR model's results(0.91.)were highly correlated with the target HMI magnetographs as indicated by the correlation coefficient ***,the method achieved the best PSNR,SSIM,MAE and RMSE values,indicating that the MESR model can effectively reconstruct magnetograms.

关键词： magnetic fields techniques:image processing virtual observatory tools Sun:magnetic fields

Effect of the vortical structures on the hydrodynamic performance of a pitching hydrofoil

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Journal of Hydrodynamics 2024年第2期36卷 406-420页

作者： Rui Yuan hui-yun Hao {1. Wu Yun-{1.g Liu Biao Huang School of Mechanical Engineering Beijing Institute of TechnologyBeijing100081China

The objective is to study the vortical structural behaviors of a transient pitching hydrofoil and their effects on the hydrodynamic performance. The pitching motion of the hydrofoil is set to pitch up with an almost constant rate from 5° to 1.° and then back to 5°, with the Reynolds number 4.4×1.^(5) and the frequency 2 Hz. The results show that the main coherent structures around the pitching hydrofoil include small-scale laminar separation bubble (LSB), large-scale second vortex (SV) and trailing edge vortex (TEV) which are all vortical. The relationship between the vortical structure and the lift is investigated with the finite-domain impulse theory. It indicates that the major part of the lift is contributed by the LSB, whereas the shedding and the formation of the SV and TEV cause the fluctuation of the lift. The proper orthogonal decomposition (POD) method is applied to capture the most energetic modes, revealing that the LSB mode occupies a large amount of energy in the flow field. The dynamic mode decomposition (DMD) method accurately extracts the dominant frequency and modal characteristics, with the first mode corresponding to the mean flow, the second mode corresponding to the LSB structure and the third and fourth modes corresponding to the vortex shedding.

关键词： Hydrodynamics vortical structures finite-domain impulse theory proper orthogonal decomposition(POD) dynamic mode decomposition(DMD) Pitching hydrofoil

Cancer organoids:A platform in basic and translational research

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Genes & Diseases 2024年第2期11卷 614-632页

作者： Xin Ma qin Wang Guozheng Li {1. Li Shouping Xu Da Pang Department of Breast Surgery Harbin Medical University Cancer HospitalHarbinHeilongjiang 150081China Sino-Russian Medical Research Center Harbin Medical University Cancer HospitalHarbinHeilongjiang 150081China Heilongjiang Academy of Medical Sciences HarbinHeilongjiang 150086China Department of Pharmacology (The State-Province Key Laboratories of Biomedicine-Pharmaceutics of China) College of Pharmacy of Harbin Medical UniversityHarbinHeilongjiang 150086China

An accumulation of previous work has established organoids as good preclinical models of human tumors,facilitating translation from basic research to clinical *** are changing the paradigm of preclinical cancer research because they can recapitulate the heterogeneity and pathophysiology of human cancers and more closely approximate the complex tissue environment and structure found in clinical tumors than in vitro cell lines and animal ***,the potential applications of cancer organoids remain to be comprehensively *** the review,we firstly describe what is currently known about cancer organoid culture and then discuss in depth the basic mechanisms,including tumorigenesis and tumor metastasis,and describe recent advances in patient-derived tumor organoids(PDOs)for drug screening and immunological ***,the present challenges faced by organoid technology in clinical practice and its prospects are *** review highlights that organoids may offer a novel therapeutic strategy for cancer research.

关键词： Drug assays Immunotherapy Mechanism research Organoids Precision medicine

Insight into vertical piezoelectric characteristics regulated thermal transport in van der Waals two-dimensional materials

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Rare Metals 2024年第2期43卷 770-779页

作者： Dong-Hai Wei E Zhou Jin-Yuan Xu hui-Min Wang Chen Shen Hong-Bin Zhang Zhen-Zhen {1. Guang-Zhao {1. State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan UniversityChangsha410082China Hunan Key Laboratory for Micro-Nano Energy Materials and Device and School of Physics and Optoelectronics Xiangtan UniversityXiangtan411105China Institute of Materials Science Technical University of DarmstadtAlarich-Weiss-Str.264287DarmstadtGermany School of Physics and Microelectronics Zhengzhou UniversityZhengzhou450001China

The urgent demand of extreme(ultra-high/low)thermal conductivity materials is triggered by the high-power device,where exploring the theories and mechanisms of regulating thermal transport properties plays a key ***,we elaborately investigate the effect of vertical(out-of-plane)piezoelectric characteristics on thermal transport,which is historically *** different stacking-order(AA and AB)bilayer boron nitride(Bi-BN)in two-dimensional(2D)materials are selected as study *** performing state-of-the-art first-principles calculations,it is found that the polarization charge along the out-of-plane orientation ascends significantly with the increasing piezoelectric response in AB stacked Bi-BN(Bi-BN-AB)followed by the enhanced interlayer B–N atomic ***,the amplitude of phonon anharmonicity in Bi-BN-AB increases larger than that in the AA stacked Bi-BN(Bi-BN-AA),resulting in the dramatic weakening of the thermal conductivity by 20.34%under 1.%*** research reveals the significant role of the vertical(out-of-plane)piezoelectric characteristic in regulating thermal transport and provides new insight into accurately exploring the thermal transport performance of 2D van der Waals materials.

关键词： Thermal conductivity Piezoelectric effect 2D materials Bilayer BN Strain engineering

Sparse antenna array design methodologies:A review

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Journal of Electronic Science and Technology 2024年第3期22卷 1-15页

作者： Pan Wu Yan-hui Liu Zhi-{1. Zhao {1.g-Huo Liu School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China Eastern Institute of Technology Ningbo315200China

Designing a sparse array with reduced transmit/receive modules(TRMs)is vital for some applications where the antenna system’s size,weight,allowed operating space,and cost are *** arrays exhibit distinct architectures,roughly classified into three categories:Thinned arrays,nonuniformly spaced arrays,and clustered *** numerous advanced synthesis methods have been presented for the three types of sparse arrays in recent years,a comprehensive review of the latest development in sparse array synthesis is *** work aims to fill this gap by thoroughly summarizing these *** study includes synthesis examples to facilitate a comparative analysis of different techniques in terms of both accuracy and ***,this review is intended to assist researchers and engineers in related fields,offering a clear understanding of the development and distinctions among sparse array synthesis techniques.

关键词： Clustered array Nonuniformly spaced array Sparse antenna array Synthesis method Thinned array

Eco-friendly polysaccharide coatings for antifouling and dragreduction and potential application for marine devices

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Friction 2024年第4期12卷 726-744页

作者： Hao YANG Liguo qin Wen{1. ZHAO Fagla Jules MAWIGNON {1. GUO Yongkang WU Yali ZHANG Guangneng DONG Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System Institute of Design Science and Basic ComponentsSchool of Mechanical EngineeringXi’an Jiaotong UniversityXi’an 710049China Key Laboratory of Biomedical Information of Ministry of Education School of Life Science and TechnologyXi’an Jiaotong UniversityXi’an 710049China Department of Endocrinology First Affiliated Hospital of Medical CollegeXi'an Jiaotong UniversityXi’an 710061China

Traditional antifouling agents usually have a certain toxic effect on marine environments and non-target *** this study,Dictyophora indusiata polysaccharide(DIP)was applied as a natural antifouling surface modifier to prepare the surface coating for marine *** DIP coatings were prepared:*** spore polysaccharide(DISP),*** volva polysaccharide(DIVP),and *** embryonic body polysaccharide(DIEP).The antifouling,tribological,and anticorrosion behavior of the coatings were *** revealed that the three kinds of DIP coatings had excellent antifouling properties,which could effectively prevent the adhesion of Chlorella and the attachment of water-based and oily stains on the ***,the coatings showed great mechanical stability and could maintain an extremely low coefficient of friction(COF<0.05)after continuous *** drag reduction rate of the coated surfaces reached 5%,showing a powerful lubrication ***,the DIP coatings presented an outstanding corrosion resistance,where the equivalent circuit impedances were 4-9 orders of magnitude higher than the control *** research showed a promising prospect of surface coating fabrication with DIP for marine devices to achieve the purpose of antifouling and drag reduction.

关键词： Dictyophora indusiata polysaccharide(DIP)coating antifouling anticorrosion lubrication and drag reduction