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Ambarzumyan's Theorem for the Dirac Operator on Equilateral Tree Graphs

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 568-576页

作者： Dong-Jie wu xin-Jian XU Chuan-Fu YANG Department of Mathematics School of Mathematics and StatisticsNanjing University of Science and TechnologyNanjing 210094China

The classical Ambarzumyan’s theorem states that if the Neumann eigenvalues of the Sturm-Liouville operator-d^(2)/dx^(2)+q with an integrable real-valued potential q on[0,π] are {n^(2):n≥0},then q=0 for almost all x∈[0,π].In this work,the classical Ambarzumyan’s theorem is extended to the Dirac operator on equilateral tree *** prove that if the spectrum of the Dirac operator on graphs coincides with the unperturbed case,then the potential is identically zero.

关键词： dirac operator quantum graph Ambarzumyan’s theorem inverse spectral problem

New food sources and production systems:a comparison of international regulations and China’s advancements in novel foods with synthetic biology

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Food Science and Human Wellness 2024年第5期13卷 2519-2542页

作者： xin Liu Di wu Yi Shao Yongning wu Key Laboratory for Deep Processing of Major Grain and Oil(The Chinese Ministry of Education) College of Food Science and EngineeringWuhan Polytechnic UniversityWuhan 430023China Institute for Global Food Security School of Biological SciencesBelfast B795DLUnited Kingdom NHC Key Laboratory of Food Safety Risk Assessment China National Center for Food Safety Risk AssessmentBeijing 100021China Department of Nutrition and Food Safety Peking Union Medical CollegeResearch Unit of Food SafetyChinese Academy of Medical SciencesBeijing 100021China

The global shift towards sustainable food systems has sparked innovations in food sources and production systems,including cell-based meat,plant-based food products,precision fermentation,and 3D food *** advancements pose regulatory challenges and opportunities,with China emerging as a critical player in adopting and regulating new food *** review explores the international landscape of new food sources and production systems(NFPS),focusing on China’s role and regulatory approaches compared to global *** this comparative analysis,we aim to contribute to the ongoing dialogue on food safety regulation,offering insights and recommendations for policymakers,industry stakeholders,and researchers engaged in the global food system’s *** comprehensive overview underscores the dynamic nature of regulatory frameworks governing NFPS,highlighting the international efforts to ensure food safety,consumer protection,and the sustainable evolution of the food industry.

关键词： New food sources Food production system Food safety International regulation Synthetic biology China

Simulation study on cuttings transport of the backreaming operation for long horizontal section wells

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Petroleum Science 2024年第2期21卷 1149-1170页

作者： Yu-Fei Chen Hui Zhang Wen-xin wu Jun Li Yong Ouyang Zong-Yu Lu De-xin Ma Yong-Chuan wu Jun-Bo Liu Ke-Rou Liu Zhuo-xin Dong China University of Petroleum(Beijing) Beijing102249China Beijing Normal University at Zhuhai Experimental and Practical Education Innovation CenterZhuhai519087GuangdongChina Oil&Gas Technology Research Institute of PetroChina Changqing Oilfield Company Xi'an710016ShaanxiChina PetroChina xinjiang Oilfield Company Karamay834002XinjiangChina China Oilfield Services Ltd. Tianjin300459China

The backreaming operation plays a significant role in safe drilling for horizontal wellbores, while it may cause severe stuck pipe accidents. To lower the risk of the stuck pipe in backreaming operations, the mechanism of cuttings transport needs to be carefully investigated. In this research, a transient cuttings transport with multiple flow patterns model is developed to predict the evolution of cuttings transported in the annulus while backreaming. The established model can provide predictions of the distribution of cuttings bed along the wellbore considering the bulldozer effect caused by large-size drilling tools(LSDTs). The sensitivity analyses of the size of LSDTs, and backreaming operating parameters are conducted in Section 4. And a new theory is proposed to explain the mechanism of cuttings transport in the backreaming operation, in which both the bit and LSDTs have the “cleaning effect” and “plugging effect”.The results demonstrate that the cuttings bed in annuli is in a state of dynamic equilibrium, but the overall trend and the distribution pattern are obvious. First, larger diameters and longer drilling tools could lead to a higher risk of the stuck pipe. Second, we find that it is not the case that the higher flow rate is always better for hole cleaning, so three flow-rate intervals are discussed separately under the given conditions. When the “dangerous flow rate”(35 L/s in Case 4),the higher the flow rate, the better the cleaning effect of cuttings beds. Third, an interval of tripping velocity called “dangerous velocity” is proposed, in which the cuttings bed accumulation near the LSDTs is more serious than

关键词： Backreaming Stuck pipe Hole cleaning Transient solid transport Multiple flow patterns

Stereoselective Self-Assembly of Chiral Metalla[2]Catenanes and Lemniscular Macrocycles

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CCS Chemistry 2024年第8期6卷 2000-2010页

作者： Shu-Jin bao Hai-Ning Zhang Guo-xin Jin Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials State Key Laboratory of Molecular Engineering of PolymersDepartment of ChemistryFudan UniversityShanghai 200433

Designing and stereoselectively constructing chiral mechanically interlocked molecules(MIMs)is a goal that many chemists are pursuing due to their potential in the development of functional molecular machines involved in catalysis,sensing,and chiroptical ***,the synthesis of enantiopure supramolecular entities with crystallographic structures remains ***,the stereoselective self-assembly of chiral metalla[2]catenanes interlocked by two D-shaped macrocycles was realized by combining long binuclear half-sandwich organometallic Cp*Rh^(III)(Cp*=η^(5)-pentamethylcyclopentadienyl)clip and ditopic monodentate ligand incorporating L-leucine *** resulting metalla[2]catenane displayed unique co-conformational mechanical helical chirality characteristics arising from the chirality transfer of the chiral ***,decreasing the length of the binuclear Cp*Rh^(III)clip and adjusting the steric hindrance of the amino-acid side chains(L-alanine and L-phenylalanine)in the ligands resulted in two lemniscular macrocycles with left-handed(M)-twisted conformational *** the best of our knowledge,the synthesized macrocycles are the first family of homochiral abnormal lemniscate-shaped organometallic macrocycles featuring figure-eight ***[2]catenanes and macrocycles with opposite chirality were also generated by employing corresponding D-amino acid ligands,as evidenced by single-crystal X-ray diffraction,nuclear magnetic resonance,mass,and circular dichroism *** present study demonstrates that homochiral MIMs can be accessed readily using amino acid–containing ligands through rational molecular design.

关键词： stereoselective synthesis chirality metallacatenanes twisted macrocycles aminoacid residues

Printed Three-dimensional Anatomic Templates for Virtual Preoperative Planning Before Reconstruction of Old Pelvic Injuries： Initial Results

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Chinese Medical Journal 2015年第4期128卷 477-482页

作者： xin-bao wu Jun-Qiang Wang Chun-Peng Zhao Xu Sun Yin Shi Zi-An Zhang Yu-Neng Li Man-Yi Wang Department of Orthopaedic Trauma Beijing Jishuitan Hospital Beijing 100035 China Laboratory of Bone Tissue Engineering Beijing Research Institute of Traumatology and Orthopaedics Beijing 100035 China

Background：Old pelvis fractures are among the most challenging fractures to treat because of their complex anatomy,difficult-to-access surgical sites,and the relatively low incidence of such *** evaluation and surgical planning are necessary to achieve the pelvic ring symmetry and stable fixation of the *** goal of this study was to assess the use of three-dimensional （3D） printing techniques for surgical management of old pelvic ***：First,16 dried human cadaveric pelvises were used to confirm the anatomical accuracy of the 3D models printed based on radiographic ***,nine clinical cases between January 2009 and April 2013 were used to evaluate the surgical reconstruction based on the 3D printed *** pelvic injuries were all type C,and the average time from injury to reconstruction was 11 weeks （range：8-17 weeks）.The workflow consisted of.：（1） Printing patient-specific bone models based on preoperative computed tomography （CT） scans,（2） virtual fracture reduction using the printed 3D anatomic template,（3） virtual fracture fixation using Kirschner wires,and （4） preoperatively measuring the osteotomy and implant position relative to landmarks using the virtually defined *** models aided communication between surgical team members during the *** technique was validated by comparing the preoperative planning to the intraoperative ***：The accuracy of the 3D printed models was within *** of a model from standard CT DICOM data took 7 hours （range：6-9 hours）.Preoperative planning using the 3D printed models was feasible in all *** correlation was found between the preoperative planning and postoperative follow-up X-ray in all nine *** patients were followed for 3-29 months （median：5 months）.The fracture healing time was 9-17 weeks （mean：l0 weeks）.No delayed incision healing,wound infection,or nonunions *** results were excellent in two cases,good in f

关键词： Old Fracture Pelvis Preoperative Planning Surgery Three-dimensional Printing

Impacts of Future Changes in Heavy Precipitation and Extreme Drought on the Economy over South China and Indochina

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Advances in Atmospheric Sciences 2024年第6期41卷 1184-1200,I0022-I0034页

作者： Bin TANG Wenting HU Anmin DUAN Yimin LIU Wen bao Yue xin Xianyi YANG State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 101408China State Key Laboratory of Marine Environmental Science College of Ocean and Earth SciencesXiamen UniversityXiamen 361005China Chinese Academy of Sciences the CAS Institutes of Science and DevelopmentBeijing 101408China School of Public Policy and Management University of Chinese Academy of SciencesBeijing 101408China

Heavy precipitation and extreme drought have caused severe economic losses over South China and Indochina(INCSC)in recent *** the areas with large gross domestic product(GDP)in the INCSC region are distributed along the coastline and greatly affected by global warming,understanding the possible economic impacts induced by future changes in the maximum consecutive 5-day precipitation(RX5day)and the maximum consecutive dry days(CDD)is critical for adaptation planning in this *** on the latest data released by phase 6 of the Coupled Model Intercomparison Project(CMIP6),future projections of precipitation extremes with bias correction and their impacts on GDP over the INCSC region under the fossil-fueled development Shared Socioeconomic Pathway(SSP5-8.5)are *** indicate that RX5day will intensify robustly throughout the INCSC region,while CDD will lengthen in most regions under global *** changes in climate consistently dominate the effect on GDP over the INCSC region,rather than the change of *** only considering the effect of climate change on GDP,the changes in precipitation extremes bring a larger impact on the economy in the future to the provinces of Hunan,Jiangxi,Fujian,Guangdong,and Hainan in South China,as well as the Malay Peninsula and southern Cambodia in ***,timely regional adaptation strategies are urgent for these ***,from the sub-regional average viewpoint,over two thirds of CMIP6 models agree that maintaining a lower global warming level will reduce the economic impacts from heavy precipitation over the INCSC region.

关键词： CMIP6 heavy precipitation extreme drought South China Indochina economic impact

Microstructure and mechanical properties of a cast TRIP-assisted multiphase stainless steel

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China Foundry 2024年第3期21卷 221-228页

作者： Meng-xin Wang Zi-xiang wu Jing-yu He Xiang Chen School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology Ministry of EducationBeijing 100084China

Stainless steels are used in a wide range of complex environments due to their excellent corrosion *** stainless steels can offer an excellent combination of strength,toughness and corrosion resistance due to the coexistence of different *** microstructure and mechanical properties of a novel cast multiphase stainless steel,composed of martensite,ferrite,and austenite,were investigated following appropriate heat treatment processes:solution treatment at 1,050℃ for 0.5 h followed by water quenching to room temperature,and aging treatment at 500℃ for 4 h followed by water quenching to room *** show reversed austenite is formed by diffusion of Ni element during aging process,and the enrichment of Ni atoms directly determines the mechanical stability of *** austenite with a lower Ni content undergoes a martensitic transformation during plastic *** tensile strength of the specimen exceeds 1,100 MPa and the elongation exceeds 24%after solid solution,and further increases to 1,247 MPa and 25%after aging *** enhancement is due to the TRIP effect of austenite and the precipitation of the nanoscale G-phase pinning dislocations in ferrite and martensite.

关键词： multiphase stainless steel mechanical properties TRIP effect reversed austenite G-phase

Effects of NLRP3 Inflammasome Mediated Pyroptosis on Cardiovascular Diseases and Intervention Mechanism of Chinese Medicine

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Chinese Journal of Integrative Medicine 2024年第5期30卷 468-479页

作者： ZHONG Yi LI xin-yue LIANG Tian-jun DING bao-zhu MA Ke-xin REN Wen-xuan LIANG Wen-jie College of Integrated Traditional Chinese and Western Medicine Hebei University of Chinese MedicineHebei Key Laboratory of Integrated Traditional Chinese and Western Medicine in Liver and Kidney DiseasesInstitute of Integrated Traditional Chinese and Western MedicineShijiazhuang 050200China Department of Cardiovascular Internal Medicine the Second Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi Province 332000China Graduate School Hebei Medical UniversityShijiazhuang 050017China Rural Physician College Hebei Medical UniversityShijazhuang 050017China Medical Department the First Hospital of Hebei Medical UniversityShijiazhuang 050030China

Activation of the NOD-like receptor protein 3(NLRP3)inflammasome signaling pathway is an important mechanism underlying myocardial pyroptosis and plays an important role in inflammatory damage to myocardial tissue in patients with cardiovascular diseases(CVDs),such as diabetic cardiomyopathy,ischemia/reperfusion injury,myocardial infarction,heart failure and *** RNAs(nc RNAs)are important regulatory *** Chinese medicine(CM)compounds,including their effective components,can regulate pyroptosis and exert myocardium-protecting *** mechanisms underlying this protection include inhibition of inflammasome protein expression,Toll-like receptor 4–NF-κB signal pathway activation,oxidative stress,endoplasmic reticulum stress(ERS),and mixed lineage kinase 3 expression and the regulation of silent information regulator *** NLRP3 protein is an important regulatory target for CVD prevention and treatment with *** the effects of the interventions mediated by CM and the related mechanisms provides new ideas and perspectives for CVD prevention and treatment.

关键词： pyroptosis cardiovascular diseases Chinese medicine NOD-like receptor protein 3 mechanisms

Oral administration of egg white ovotransferrin prevents osteoporosis in ovariectomized rats

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Food Science and Human Wellness 2024年第5期13卷 2562-2572页

作者： Nan Shang Xiaoyu bao Michael Doschak Jianping wu Department of Agricultural Food and Nutritional ScienceUniversity of AlbertaEdmonton T6G 2P5Canada College of Engineering China Agricultural UniversityBeijing 100083China Key Laboratory of Precision Nutrition and Food Quality Department of Nutrition and HealthyChina Agricultural UniversityBeijing 100193China Faculty of Pharmacy&Pharmaceutical Sciences University of AlbertaEdmonton T6G 2H5Canada

Ovotransferrin,an iron-binding glycoprotein,accounting for approximately 12%of egg white protein,is a member of transferrin fam *** previous studies showed that ovotransferrin stimulates the proliferation and differentiation of osteoblasts,while inhibits osteoclastogenesis and resorption *** work aims to study the efficacy of orally administered ovotransferrin on the prevention of osteoporosis using ovariectomized(OVX)Sprague-Dawley *** administration of ovotransferrin showed no negative effect on body weight,food intake and organ *** 12-week treatment,feeding ovotransferrin at a dose of 1%(1 g ovotransferrin/100 g diet)prevented OVX-induced bone loss and maintained relatively high bone mineral density and integrated bone *** serum concentration of biomarkers indicating bone formation was increased in ovotransferrin administration groups,while the bone resorption biomarkers were *** feeding also decreased the production of serum cytokine TNF-αand IL-6,which are two stimulators for osteoclast *** addition to its direct regulatory role on bone turnover,ovotransferrin supplementation might benefit osteoporosis prevention by inhibiting adipogenesis,and regulating immune *** results suggested the potential application of ovotransferrin as a functional food ingredient on the prevention of osteoporosis.

关键词： Ovotransferrin Ovariectomized(OVX)rats Bone mineral density Bone microarchitecture Bone resorption Inflammation