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Spacelike Framed Curves with lightlike Components and Singularities of Their Evolutes and Focal Surfaces in Minkowski 3-space

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Acta Mathematica Sinica,English Series 2024年第6期40卷 1521-1532页

作者： Peng cheng li Dong He pei Xin ZHAO School of Mathematics and Statistics Northeast Normal UniversityChangchun 130024P.R.China Department of Mathematics Harbin Institute of TechnologyWeihai 264209P.R.China School of Mathematics and Statistics Qingdao UniversityQingdao 266071P.R.China

In this paper,we define the evolute and focal surface of a spacelike framed curve with lightlike components in Minkowski 3-space.It is a generalization of the previous results of regular spacelike curves,since singularities are allowed in the original spacelike curves studied by spacelike framed curves with lightlike components.Meanwhile,we show a new geometric invariant to characterise singularities of the focal surface.Then,the classification theorem and recognition theorem for the singularities of the focal surface in generic are also given.

关键词： Evolutes focal surfaces spacelike framed curves singularities

Sustainable production of high-energy-density jet fuel via cycloaddition reactions

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Journal of Energy Chemistry 2024年第8期95卷 712-722页

作者： Yan-cheng Hu Yingying Zhao Ning li Jing-pei Cao School of Chemical Engineering and Technology China University of Mining and Technology School of Education Science Jiangsu Normal University CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Developing an energy supply-chain based on renewable biomass holds great potential to build a low carbon society. High-energy-density(HED) jet fuel, featuring unique fused/strained cycloalkanes, is of great significance for volume-limited military aircrafts, as their high density and combustion heat can extend flight duration and increase the payload. Therefore, the exploration of biomass-based routes towards HED fuel has drawn much attention over the past decade. Cycloaddition reaction features rapid construction of various carbocycles in an atom-and step-economical fashion. This elegant strategy has been widely applied in the manufacture of sustainable HED fuel. Here we carefully summarize the progress achieved in this fascinating area and the review is categorized by the cycloaddition patterns including [4+2], [2+2],[4+4], and [2+1] cycloadditions. Besides, the energy densities of the as-prepared biofuels and petroleumbased fuels(conventional Jet-A and advanced JP-10) are also compared. This review will provide important insights into rational design of new HED fuel with different ring-types/sizes and inspire the chemists to turn those literature studies into practical applications in military field.

关键词： Biomass-based chemicals Catalysis Cycloaddition Cycloalkanes High-energy-density fuel

One-year observation of the mixing states of oxygenated organics-containing single particles in Guangzhou,China

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Frontiers of Environmental Science & Engineering 2024年第5期18卷 155-169页

作者： liyuan Mao Suxia Yang Xiaoya cheng Sulin liu Duanying Chen Zhen Zhou Mei li chenglei pei Chunlei cheng Institute of Mass Spectrometry and Atmospheric Environment Guangdong Provincial Engineering Research Center for the On-line Source Apportionment System of Air PollutionJinan UniversityGuangzhou510632China Guangdong-Hongkong-Macao Joint Laboratory of Collaborative Innovation for Environmental Quality Guangzhou510632China Guangzhou Research Institute of Environment Protection Co. Ltd.Guangzhou510620China Guangzhou Ecological and Environmental Monitoring Center of Guangdong Province Guangzhou510030China State Key Laboratory of Marine Resource Utilization in South China Sea Hainan UniversityHaikou570228China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy SciencesXi’an710061China

Oxygenated organic molecules(OOMs)play an important role in the formation of secondary organic aerosols(SOAs),but the mixing states of OOMs are still unclear.This study investigates the mixing states of OOM-containing single particles from the measurements taken using a single particle aerosol mass spectrometer in Guangzhou,China in 2022.Generally,the particle counts of OOM particles and the mass concentration of secondary organic carbon(SOC)exhibited similar temporal trends throughout the entire year.The OOM particles were consistently enriched in secondary ions,including 16O−,26CN−,46NO2−,62NO3−,and 97HSO4−.In contrast,the number fractions and diurnal patterns of OOM particles among the total detected particles showed similar distributions in August and October;however,the SOC ratios in fine particulate matter were quite different,suggesting that there were different mixing states of single-particle oxygenated organics.In addition,further classification results indicated that the OOM particles were more aged in October than August,even though the SOC ratios were higher in August.Furthermore,the distribution of hydrocarbon fragments exhibited a notable decrease from January to October,emphasizing the more aged state of the organics in October.In addition,the sharp increase in elemental carbon(EC)-OOM particles in the afternoon in October suggests the potential role of EC in the aging process of organics.Overall,in contrast to the bulk analysis of SOC mass concentration,the mixing states of the OOM particles provide insights into the formation process of SOAs in field studies.

关键词： Oxygenated organics Single particles Mixing state Secondary formation Photochemistry

Advances in methane emissions from agricultural sources:Part I.Accounting and mitigation

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Journal of Environmental Sciences 2024年第6期140卷 279-291页

作者： Xiaokun Wu Ying Zhang Yinghui Han Yagang Zhang Yuhang Zhang Xiaodan cheng pei Zhong Xue Yuan Yuanxun Zhang Zhengqiang li State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China Hebei Key Laboratory of Physics and Energy Technology North China Electric Power UniversityBaoding 071003China College of Resources and Environment University of Chinese Academy of SciencesBeijing 101408China Interdisciplinary Mathematics Institute University of South CarolinaColumbiaSC 29208United States Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China

Methane is one of the major greenhouse gases(GHGs)and agriculture is recognized as its primary emitter.Methane accounting is a prerequisite for developing effective agriculture mitigation strategies.In this review,methane accounting methods and research status for various agricultural emission source including rice fields,animal enteric fermentation and livestock and poultry manure management were overview,and the influencing factors of each emission source were analyzed and discussed.At the same time,it analyzes the different research efforts involving agricultural methane accounting and makes recommendations based on the actual situation.Finally,mitigation strategies based on accounting results and actual situation are proposed.This review aims to provide basic data and reference for agriculture-oriented countries and regions to actively participate in climate action and carry out effective methane emission mitigation.

关键词： Methane emission Agricultural sources Accounting methodology Mitigation Emission influencing factors

Exponential Synchronization of Delayed Stochastic Complex Dynamical Networks via Hybrid Impulsive Control

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 785-787页

作者： Yao Cui pei cheng Xiaohua Ge the School of Mathematic Science Anhui UniversityHefei 230601China IEEE the School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyMelbourne VIC 3122Australia

Dear Editor,This letter addresses the synchronization problem of a class of delayed stochastic complex dynamical networks consisting of multiple drive and response nodes.The aim is to achieve mean square exponential synchronization for the drive-response nodes despite the simultaneous presence of time delays and stochastic noises in node dynamics.

关键词： dynamics stochastic letter

Spatial-Temporal Analysis of Drinking Water Type of Endemic Fluorosis—China,2009–2022

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China CDC weekly 2024年第2期6卷 25-29页

作者： lijun Zhao Zhe li Mang li Hongna Sun Wei Wei lin Gao Qiaoshi Zhao Yang liu Xiaohong Ji cheng li Jian Wang Yanhui Gao Junrui pei Center for Endemic Disease Control Chinese Center for Disease Control and PreventionHarbin Medical UniversityHarbin CityHeilongjiang ProvinceChina Key Lab of Etiology and Epidemiology Education Bureau of Heilongjiang Province(23618504)Ministry of Health of PRHarbin Medical UniversityHarbin CityHeilongjiang ProvinceChina

What is already known about this topic?Endemic fluorosis,caused by high fluoride levels in drinking water,has been a significant health issue in rural areas of China for many decades.What is added by this report?There has been a notable decline in the detection rate of dental fluorosis in children aged 8–12 years in drinking water fluorosis areas across the country from 2009 to 2022.While 14 provincial-level administrative divisions are classified as low-probability clusters,Tianjin remains classified as a high-probability cluster.What are the implications for public health practice?The current policy for preventing and controlling endemic fluorosis in China needs adjustment.Rather than focusing solely on regions with high incidence,there should be a shift towards monitoring and early warning of fluoride exposure.Additionally,local containment measures should be intensified.

关键词： intensified Spatial fluoride

Research progress of bariatric embolization for treatment of obesity

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Chinese Medical Journal 2019年第7期132卷 880-882页

作者： Bin-Yan Zhong pei-cheng li Cai-Fang Ni Department of Interventional Radiology The First Affiliated Hospital of Soochow UniversitySuzhouJiangsu 215006China

To the Editor:The prevalence of obesity,defined as body mass index(BMI)≥30 kg/m^2,is increasing worldwide and has been identified that obesity is a risk factor for several kinds of chronic diseases.[1]According to the severity of obesity,associated coexisting chronic diseases,and functional limitations,therapies for obesity include lifestyle intervention(eg,diet and exercise),pharmacotherapy,endoscopic bariatric therapies,bariatric surgery,and bariatric embolization(BAE).

关键词： bariatric embolization treatment obesity

GATA binding protein 2 mediated ankyrin repeat domain containing 26 high expression in myeloid-derived cell lines

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World Journal of Stem Cells 2024年第5期16卷 538-550页

作者： Yang-Zhou Jiang Lan-Yue Hu Mao-Shan Chen Xiao-Jie Wang cheng-Ning Tan pei-pei Xue Teng Yu Xiao-Yan He li-Xin Xiang Yan-Ni Xiao Xiao-liang li Qian Ran Zhong-Jun li li Chen Laboratory of Radiation Biology Department of Blood TransfusionLaboratory Medicine CenterThe Second Affiliated HospitalThird Military Medical UniversityChongqing 400037China Hematopoietic Acute Radiation Syndrome Medical and Pharmaceutical Basic Research Innovation Center Ministry of Education of the People’s Republic of ChinaChongqing 400037China

BACKGROUND Thrombocytopenia 2,an autosomal dominant inherited disease characterized by moderate thrombocytopenia,predisposition to myeloid malignancies and normal platelet size and function,can be caused by 5’-untranslated region(UTR)point mutations in ankyrin repeat domain containing 26(ANKRD26).Runt related transcription factor 1(RUNX1)and friend leukemia integration 1(Fli1)have been identified as negative regulators of ANKRD26.However,the positive regulators of ANKRD26 are still unknown.AIM To prove the positive regulatory effect of GATA binding protein 2(GATA2)on ANKRD26 transcription.METHODS Human induced pluripotent stem cells derived from bone marrow(hiPSC-BM)INTRODUCTION Ankyrin repeat domain containing protein 26(ANKRD26)acts as a regulator of adipogenesis and is involved in the regulation of feeding behavior[1-3].The ANKRD26 gene is located on chromosome 10 and shares regions of homology with the primate-specific gene family POTE.According to the Human Protein Atlas database,the ANKRD26 protein is localized to the Golgi apparatus and vesicles,and its expression can be detected in nearly all human tissues[4].Moreover,UniProt annotation revealed that ANKRD26 is localized in the centrosome and contains coiled-coil domains formed by spectrin helices and ankyrin repeats[5,6].The most common disease related to ANKRD26 is thrombocytopenia 2(THC2),which is a rare autosomal dominant inherited disease characterized by lifelong mild-to-moderate thrombocytopenia and mild bleeding[7-9].Caused by the variants in the 5’-untranslated region(UTR)of ANKRD26,THC2 is defined by a decrease in the number of platelets in circulating blood and results in increased bleeding and decreased clotting ability[8,10].Due to the point mutations that occur in the 5’-UTR of ANKRD26,its negative transcription factors(TFs),Runt related transcription factor 1(RUNX1)and friend leukemia integration 1(Fli1),lose their repression effect[11].The persistent expression of ANKRD26 increases the activity of the mitogen activated protein kinase and e

关键词： Ankyrin repeat domain containing 26 GATA binding protein 2 Thrombocytopenia 2 Transcriptional regulation Myeloid-derived cell lines

Recent progress in functional modification and crosslinking of bioprosthetic heart valves

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Regenerative Biomaterials 2024年第1期3卷 1-16页

作者： cheng Zheng li Yang Yunbing Wang National Engineering Research Center for Biomaterials Sichuan UniversityChengdu 610064China

Valvular heart disease(VHD),clinically manifested as stenosis and regurgitation of native heart valve,is one of the most prevalent cardiovascular diseases with high mortality.Heart valve replacement surgery has been recognized as golden standard for the treatment of VHD.Owing to the clinical application of transcatheter heart valve replacement technic and the excellent hemodynamic performance of bioprosthetic heart valves(BHVs),implantation of BHVs has been increasing over recent years and gradually became the preferred choice for the treatment of VHD.However,BHVs might fail within 10-15 years due to structural valvular degeneration(SVD),which was greatly associated with drawbacks of glutaraldehyde crosslinked BHVs,including cytotoxicity,calcification,component degradation,mechanical failure,thrombosis and immune response.To prolong the service life of BHVs,much effort has been devoted to overcoming the drawbacks of BHVs and reducing the risk of SVD.In this review,we summarized and analyzed the research and progress on:(i)modification strategies based on glutaraldehyde crosslinked BHVs and(ii)nonglutaraldehyde crosslinking strategies for BHVs.

关键词： bioprosthetic heart valves modification crosslinking anticalcification antithrombosis