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Blood lead levels among children aged 0 to 6 years in 16 cities of China, 2004-2008

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Chinese Medical Journal 2013年第12期126卷 2291-2295页

作者： XIE Xiao-hua TAN Zang-wen jia ni FAN Zhao-yang ZHANG Shuai-ming Lu Yan-yu CHEN Li DAI Yao-hua Department of Integrated Early Childhood Development Capital Institute of Paediatrics Beijing 100020 China

Background The adverse health effects of lead for children under 6 years are well *** to assess the lead exposure among children in China are small in sample size and lack of national representative *** aim of this study therefore was to describe blood lead levels and identify risk factors for lead exposure among children aged 0 to 6 years living in 16 cities in *** We analyzed data from blood lead levels surveillance in China carried out in 16 large cities between 2004 and 2008.A stratified clustered random sampling strategy was used.A total of 69 968 children aged 0 to 6 years were *** conducted multiple Logistic regression analyses to explore risk factors to high blood lead *** The geometric mean blood lead level of the children was 4.50 μg/dl （median：4.90 μg/dl; IQR：3.20-7.00 μg/dl）.Overall prevalence of blood lead level ≥10.00 μg/dl among 0-to 6-year-old children was 7.57%.But the proportion of blood lead level ≥5.00 but 〈10.00 μg/dl was 42.12%.Blood lead levels were significantly higher in boys （4.63 μg/dl） than in girls （4.35 μg/dl）（P 〈0.0001）.The geometric mean blood lead levels and prevalence of blood lead level ≥10.00 μg/dl increased with age （P 〈0.0001 for the two trends）.After controlling for sociodemographic,dietary and behavior factors,multivariable analysis indicated that lower maternal education,male gender,younger age,often biting pencil or/and toys,walking or playing for long time on the street,not washing hands before eating are major risk factors for higher lead *** The blood lead levels among Chinese children in urban areas are lower than previous studies but close to those of developed ***,children with low lead exposure account for almost half and the sociodemographic factors （age,male sex,and low mother education level） continue to be associated with higher blood lead levels.

关键词： children lead poisoning blood lead risk factors

Grid-Connected/Islanded Switching Control Strategy for Photovoltaic Storage Hybrid Inverters Based on Modified Chimpanzee Optimization Algorithm

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Energy Engineering 2025年第1期122卷 265-284页

作者： Chao Zhou NarisuWang Fuyin ni wenchao Zhang School of Electrical and Information Engineering Jiangsu University of TechnologyChangzhou213001China jiangsu Key Laboratory of Power Transmission&Distribution Equipment Technology Jiangsu University of TechnologyChangzhou213001China

Uneven power distribution,transient voltage,and frequency deviations are observed in the photovoltaic storage hybrid inverter during the switching between grid-connected and island *** response to these issues,this paper proposes a grid-connected/island switching control strategy for photovoltaic storage hybrid inverters based on the modified chimpanzee optimization *** proposed strategy incorporates coupling compensation and power differentiation elements based on the traditional droop ***,it combines the angular frequency and voltage amplitude adjustments provided by the phase-locked loop-free pre-synchronization control *** pre-synchronization is achieved by regulating the virtual current to zero and aligning the photovoltaic storage hybrid inverter with the grid ***,two novel operators,learning and emotional behaviors are introduced to enhance the optimization precision of the chimpanzee *** operators ensure high-precision and high-reliability optimization of the droop control parameters for photovoltaic storage hybrid inverters.A Simulink model was constructed for simulation analysis,which validated the optimized control strategy’s ability to evenly distribute power under load *** strategy effectively mitigated transient voltage and current surges during mode ***,seamless and efficient switching between gridconnected and island modes was achieved for the photovoltaic storage hybrid *** enhanced energy utilization efficiency,in turn,offers robust technical support for grid stability.

关键词： Photovoltaic storage hybrid inverters modified chimpanzee optimization algorithm droop control seamless switching

Exosomes:the next-generation therapeutic platform for ischemic stroke

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Neural Regeneration Research 2025年第5期20卷 1221-1235页

作者： wenjing Yin Hongyin Ma Yang Qu jiaxin Ren Yingying Sun Zhen-ni Guo Yi Yang Stroke Center Department of NeurologyFirst Hospital of Jilin UniversityChangchunJilin ProvinceChina Neuroscience Research Center Department of NeurologyFirst Hospital of Jilin UniversityChangchunJilin ProvinceChina

Current therapeutic strategies for ischemic stroke fall short of the desired objective of neurological functional ***,there is an urgent need to develop new methods for the treatment of this *** are natural cell-derived vesicles that mediate signal transduction between cells under physiological and pathological *** have low immunogenicity,good stability,high delivery efficiency,and the ability to cross the blood–brain *** physiological properties of exosomes have the potential to lead to new breakthroughs in the treatment of ischemic *** rapid development of nanotechnology has advanced the application of engineered exosomes,which can effectively improve targeting ability,enhance therapeutic efficacy,and minimize the dosages *** in technology have also driven clinical translational research on *** this review,we describe the therapeutic effects of exosomes and their positive roles in current treatment strategies for ischemic stroke,including their antiinflammation,anti-apoptosis,autophagy-regulation,angiogenesis,neurogenesis,and glial scar formation reduction ***,it is worth noting that,despite their significant therapeutic potential,there remains a dearth of standardized characterization methods and efficient isolation techniques capable of producing highly purified *** optimization strategies should prioritize the exploration of suitable isolation techniques and the establishment of unified workflows to effectively harness exosomes for diagnostic or therapeutic applications in ischemic ***,our review aims to summarize our understanding of exosome-based treatment prospects in ischemic stroke and foster innovative ideas for the development of exosome-based therapies.

关键词： blood–brain barrier electroacupuncture engineering exercise exosomes ischemic stroke mesenchymal stem cells microglia neuroprotection stents

Based on non-targeted metabolomics for differential components screening of Rosae Chinensis Flos and Rosae Rugosae Flos and their quality evaluation

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Traditional Medicine Research 2025年第2期10卷 1-15页

作者： Xu Liang ni-Hui Zhang Zhi-Lai Zhan Guang-Lu Chang Yan Gao Xia Li wen-Yuan Gao School of Pharmaceutical Science and Technology Faculty of MedicineTianjin UniversityTianjin 300193China State Key Laboratory for Quality Ensurance and Sustainable Use of Dao-di Herbs China Academy of Chinese Medical SciencesBeijing 100700China Key Laboratory of Modern Chinese Medicine Resources Research Enterprises Tianjin 300402China

Background:Rosa chinensis *** Rosa rugosa *** not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional *** two plants have some differences in efficacy,but the flower buds are easily confused for similar *** addition,large-scale cultivation of ornamental rose flowers may lead to a decrease in the effective components of medicinal ***,it is necessary to study the chemical composition and make quality evaluation of Rosae Chinensis Flos(Yueji)and Rosae Rugosae Flos(Meigui).Methods:In this study,40 batches of samples including Meigui and Yueji from different regions in China were collected to establish high-performance liquid chromatography ***,the fingerprints data was analyzed using principal component analysis,hierarchical cluster analysis,and partial least squares discriminant analysis analysis chemometrics to obtain information on intergroup differences,and non-targeted metabolomic techniques were applied to identify and compare chemical compositions of samples which were chosen from groups with large *** compounds were screened by orthogonal partial least-squares discriminant analysis and S-plot,and finally multi-component quantification was performed to comprehensively evaluate the quality of Yueji and ***:The similarity between the fingerprints of 40 batches roses and the reference print R was 0.73 to 0.93,indicating that there were similarities and differences between the *** principal component analysis and hierarchical cluster analysis of fingerprints data,the samples from different origins and varieties were intuitively divided into four *** least-squares discriminant analysis analysis showed that Meigui and Yueji cluster into two categories and the model was reliable.A total of 89 compounds were identified by high resolution mass spectrometry,mainly were flavonoids and flavon

关键词： Rosa chinensis Jacq. Rosa rugosa Thunb. metabolomics chemometrics multiple component quantification quality evaluation

Integration of Electrical Properties and Polarization Loss Modulation on Atomic Fe–N‑RGO for Boosting Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第2期17卷 517-532页

作者： Kaili Zhang Yuefeng Yan Zhen Wang Guansheng Ma Dechang jia Xiaoxiao Huang Yu Zhou State Key Laboratory of Precision Welding&Joining of Materials and Structures Harbin Institute of TechnologyHarbin 150001People’s Republic of China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001People’s Republic of China MIIT Key Laboratory of Advanced Structural‑Functional Integration Materials&Green Manufacturing Technology Harbin Institute of TechnologyHarbin 150001People’s Republic of China

Developing effective strategies to regulate graphene’s conduction loss and polarization has become a key to expanding its application in the electromagnetic wave absorption(EMWA)*** on the unique energy band structure of graphene,regulating its bandgap and electrical properties by introducing heteroatoms is considered a feasible ***,metal-nitrogen doping reduced graphene oxide(M–N-RGO)was prepared by embedding a series of single metal atoms M–N_(4) sites(M=Mn,Fe,Co,ni,Cu,Zn,Nb,Cd,and Sn)in RGO using an N-coordination atom-assisted *** composites had adjustable conductivity and polarization to optimize dielectric loss and impedance matching for efficient EMWA *** results showed that the minimum reflection loss(RL_(min))of Fe–N-RGO reaches−74.05 dB(2.0 mm)and the maximum effective absorption bandwidth(EAB_(max))is 7.05 GHz(1.89 mm)even with a low filler loading of only 1 wt%.Combined with X-ray absorption spectra(XAFS),atomic force microscopy,and density functional theory calculation analysis,the Fe–N_(4) can be used as the polarization center to increase dipole polarization,interface polarization and defect-induced polarization due to d-p orbital hybridization and structural ***,electron migration within the Fe further leads to conduction loss,thereby synergistically promoting energy *** study demonstrates the effectiveness of metal-nitrogen doping in regulating the graphene′s dielectric properties,which provides an important basis for further investigation of the loss mechanism.

关键词： Electromagnetic wave absorption Fe-N-RGO Dipole polarization Conduction loss Impedance matching

Effect of solution cooling rate on the γ′ precipitation behaviors of a ni-base P/M superalloy

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Journal of University of Science and Technology Beijing 2008年第6期15卷 729-734页

作者： Gaofeng Tian Chengchang jia Ying wen Benfu Hu School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

The effect of cooling rate on the cooling γ′ precipitation behaviors was investigated in a ni-base powder/metallurgy （P/M） superalloy （FGH4096）. The empirical equations were established between the cooling rate and the average sizes of secondary and tertiary γ′ precipitates within grains and tertiary γ′ precipitates at grain boundaries, as well as the apparent width of grain boundaries. The results show that the average sizes of secondary or tertiary γ′ precipitates are inversely correlated with the cooling rate. The shape of secondary γ′ precipitates within grains changes from butterfly-like to spherical with the increase of cooling rate, but all the tertiaryγ′ precipitates formed are spherical in shape. It is also found that tertiary γ′ may be precipitated in the latter part of the cooling cycle only if the cooling rate is not faster than 4.3℃/s, and the apparent width of grain boundaries decreases linearly with the increase of cooling rate.

关键词： powder metallurgy ni-base superalloy precipitates cooling rate

Performance of a deep top-down zoned pit-in-pit excavation close to existing metro lines through winter

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Frontiers of Structural and Civil Engineering 2024年第11期18卷 1680-1697页

作者： wenxin CAO Pengjiao jia Pengpeng ni wen ZHAO Cheng CHENG Fei WANG School of Resources and Civil Engineering Northeastern UniversityShenyang 110819China School of Rail Transportation Soochow UniversitySuzhou 215131China School of Civil Engineering Sun Yat-sen UniversityZhuhai 519082China South China Engineering Co. Ltd.China Railway No.5 Engineering Group Co.Ltd.Dongguan 523160China

Though a comprehensive in situ measurement project,the performance of a deep pit-in-pit excavation constructed by the top-down method in seasonal frozen soil area in Shenyang was extensively *** measured excavation responses included the displacement of capping beam and retaining pile,settlement of ground surface,and deformation of metro *** on the analyses of field data,some major findings were obtained:1)the deformations of retaining structures fluctuated along with the increase of temperature,2)the deformation variation of retaining structures after the occurrence of thawing of seasonal frozen soil was greater than that in winter,although the excavation depth was smaller than before,3)the influence area of ground settlement was much smaller because of the features of seasonal frozen sandy soil,4)the displacement of metro line showed a significant spatial effect,and the tunnel lining had an obviously hogging displacement pattern,and 5)earth pressure redistribution occurred due to the combined effects of freezing-thawing of seasonal frozen soil and excavation,leading to the deformation of metro *** influence area of ground settlement was obviously smaller than that of Shanghai soft clay or other cases reported in literatures because of special geological conditions of ***,the deformation of metro lines was significantly lager after the thawing of the frozen soil,the stress in deep soil was redistributed,and the metro lines were forced to deform to meet a new state of equilibrium.

关键词： deep excavation metro line ground surface settlement deformation seasonal frozen soil

Isolation of CYP17 Ⅰ, 3β-HSD and AR Genes from Spotted Sea Bass (Lateolabrax maculatus) Testis and Their Responses to Hormones and Salinity Stimulations

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Journal of Ocean University of China 2019年第2期18卷 420-430页

作者： CHI Meili ni Meng jia Yongyi GU Zhimin wen Haishen Key Laboratory of Mariculture(Ocean University of China) Ministry of Education Agriculture Ministry Key Laboratory of Healthy Freshwater Aquaculture Key Laboratory of Freshwater Aquaculture Genetic and Breeding of Zhejiang Province Zhejiang Institute of Freshwater Fisheries

In this study, three cDNA sequences corresponding to cytochrome P450 C17(CYP17 Ⅰ), 3β-hydroxysteroid dehydrogenase(3β-HSD) and androgen receptor(AR) were isolated from spotted sea bass(Lateolabrax maculatus). The mRNA abundances of CYP17 Ⅰ and 3β-HSD increased from stage Ⅱ to stage V with a significant increase at stage Ⅴ, and the highest abundance of AR mRNA was detected at stage Ⅲ in testicular development cycle. CYP17 I, 3β-HSD and AR transcripts were obviously abundant in steroidogenesis tissues such as testis, brain, head kidney among others. Strong and positive signals were observed mainly in interstitial cell regions of L. maculatus testis as were measured with in situ hybridization method. Significant increases of CYP17 Ⅰ and3β-HSD transcripts were detected after 12-48 h hCG(human chorionic gonadotropin) and GnRHa(gonadotropin-releasing hormone analogue) treatments. However, an opposite relationship was found for AR in testis at the same time. In addition, decreasing trends of CYP17 Ⅰ and 3β-HSD mRNA were observed in testis of L. maculatus in freshwater group(FW) from day 2 to day 6, and mRNA abundance of AR increased in brackish water(BW) group from day 4 to day 8. These findings revealed that these three steroid synthesis genes are import for testicular development, hormone and salinity treatment, and provided also an insight into the mechanism of reproductive endocrine of L. maculatus.

关键词： L.maculatus hCG GnRHa salinity steroidogenic enzyme spermatogenesis

Ceramic-based meta-material absorber with high-temperature stability

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Rare Metals 2024年第9期43卷 4433-4440页

作者： Xing-Cong Chen Wei-jia Luo Run-ni Zhao Yong-Zheng wen Ji Zhou State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

With the continuous exploration of uncharted and extreme environments,enhanced temperature robustness of passive devices has become particularly *** this study,a ceramic-based meta-material absorber with exceptional temperature stability is developed using a fusion design approach that combines rare metal-based tungsten bronze structural ceramics and ***,the absorbance of the meta-material array based on Mie resonance exceeds 49.0%in both waveguides and free space,approaching the theoretical *** to impedance analysis,the absorption performance can be distinctly correlated with the dielectric loss(Q_(f)).Notably,the high-temperature robustness is verified to still be effective at 400℃.These advancements in our design allow for the use of monolithic materials in fabricating temperature-stable perfect absorbers,providing greater freedom in the dielectric performance and expanding their potential applications,including in space exploration and 5G millimeter-wave scenarios.

关键词： Temperature robustness Meta-material absorber Microwave absorption Rare metal-based ceramics Miniaturization