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On the Blaschke Isoparametric Hypersurfaces in the Unit Sphere

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Acta Mathematica Sinica,English Series 2009年第4期25卷 657-678页

作者： Xing xiao LI Feng yun zhang Department of Mathematics. He'nan Normal University Xinxiang 453007 P. R. China

Given an immersed submanifold x ： M^M → S^n in the unit sphere S^n without umbilics, a Blaschke eigenvalue of x is by definition an eigenvalue of the Blaschke tensor of x. x is called Blaschke isoparametric if its Mobius form vanishes identically and all of its Blaschke eigenvalues are constant. Then the classification of Blaschke isoparametric hypersurfaces is natural and interesting in the MSbius geometry of submanifolds. When n = 4, the corresponding classification theorem was given by the authors. In this paper, we are able to complete the corresponding classification for n = 5. In particular, we shall prove that all the Blaschke isoparametric hypersurfaces in S^5 with more than two distinct Blaschke eigenvalues are necessarily Mobius isoparametric.

关键词： Mobius form Blaschke eigenvalues Blaschke tensor Mobius metric Mobius second fundamental form

Synthesis of new 2,5-dimethyl pyrrole derivatives from acetonylacetone

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Chinese Chemical Letters 2010年第8期21卷 919-921页

作者： xiao Ming Ji Ye Lu Ming Qin Zhao xiao yun zhang yun Liu Le Liu National Tobacco Cultivation Physiology and Biochemistry Research Center/College of Tobacco Science Henan Agricultural UniversityZhengzhou 450002China

Acetonylacetone 1 was treated with thiourea,aniline,glycine and glutamic acid to give pyrrole derivatives 2,3,5,and 9 by Paal-Knorr reaction,*** 3 was successfully transformed into the related pyrrole derivative 4 by Mannich reaction. Compounds 6,7 and 8 were obtained by reacting 5 with phenethyl alcohol,phenylallylic alcohol and leaf alcohol by esterification reactions,*** structures of all new products were elucidated by IR,NMR and HRMS spectra.

关键词： Acetonylacetone Paal-Knorr reactions Mannich reactions Esterification reactions Synthesis

Acute inferior wall myocardial infarction induced by aortic dissection in a young adult with Marfan syndrome:A case report

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World Journal of Clinical Cases 2021年第4期9卷 970-975页

作者： yun-xiao zhang Hang Yang Gui-Song Wang Department of Cardiology Peking University Third HospitalNHC Key Laboratory of Cardiovascular Molecular Biology and Regulatory PeptidesBeijing 100191China Department of Cardiac Surgery Peking University Third HospitalBeijing 100191China

BACKGROUND Aortic dissection(AD)is an emergent and life-threatening disorder,and its inhospital mortality was reported to be as high as 24.4%-27.4%.AD can mimic other more common disorders,especially acute myocardial infarction(AMI),in terms of both symptoms and electrocardiogram *** for patients with AD may result in catastrophic *** awareness of AD can be helpful for early diagnosis,especially among younger *** SUMMARY We report a 28-year-old man with acute left side chest pain without cardiovascular risk *** was diagnosed with acute inferior ST-segment elevation myocardial infarction(STEMI),which,based on illness history,physical examination,and intraoperative findings,was eventually determined to be type A AD caused by Marfan *** coronary angiography revealed the anomalous origin of the right coronary artery as well as eccentric stenosis of the proximal ***,computed tomography angiography(CTA)showed intramural thrombosis of the ascending ***,the patient was transferred to the cardiovascular surgery department for a Bentall *** was discharged 13 d after the operation,and aortic CTA proved a full recovery at the 2-year *** It is essential and challenging to differentiate AD from *** A AD should be the primary consideration in younger STEMI patients without cardiovascular risk factors but with outstanding features of Marfan syndrome.

关键词： Aortic dissection Acute myocardial infarction Marfan syndrome Case report

Precision Plate Plan View Pattern Predictive Model

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Journal of Iron and Steel Research International 2011年第11期18卷 26-30页

作者： ZHAO Yang YANG Quan HE An-rui WANG xiao-chen zhang yun Engineering Research Institute University of Science and Technology Beijing Beijing 100083 China

According to the rolling features of plate mill, a 3D elastic-plastic FEM （finite element model） based on full restart method of ANSYS/LS-DYNA was established to study the inhomogeneous plastic deformation of multipass plate rolling. By analyzing the simulation results, the difference of head and tail ends predictive models was found and modified. According to the numerical simulation results of 120 different kinds of conditions, precision plate plan view pattern predictive model was established. Based on these models, the sizing MAS （mizushima automatic plan view pattern control system） method was designed and used on a 2 800 mm plate mill. Comparing the rolled plates with and without PVPP （plan view pattern predictive） model, the reduced width deviation indicates that the olate !olan view Dattern predictive model is preeise.

关键词： plate plan view pattern FEM LS-DYNA full restart

Mixture of Electromagnetically Induced Transparency and Autler–Townes Splitting in a Five-Level Atomic System

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Communications in Theoretical Physics 2017年第2期67卷 217-221页

作者： xiao-yun zhang Shan Wu Hai-Chao Li College of Physics and Electronic Science Hubei Normal University Huangshi 435002 China Institute for Interdisciplinary Research Jianghan University Wuhan 430056 China College of Science China Three Gorges University Yichang 443002 China

Discerning electromagnetically induced transparency(EIT) from Autler–Townes splitting(ATS) is a significant issue in quantum optics and has attracted wide attention in various three-level configurations. Here we present a detailed study of EIT and ATS in a five-level atomic system considered to be composed of a four-level Y-type subsystem and a three-level Λ-type subsystem. In our theoretical calculations with standard density matrix formalism and steadystate approximation, we obtain the general analytical expression of the first-order matrix element responsible for the probe-field absorption. In light of the well-known three-level EIT and ATS criteria, we numerically show an intersection of EIT with ATS for the Y-type subsystem. Furthermore, we show that an EIT dip is sandwiched between two ATS dips(i.e., multi-dip mixture of EIT and ATS) in the absorption line for the five-level system, which can be explained by the dressed-state theory and Fano interference.

关键词： electromagnetically induced transparency Autler–Townes splitting five-level atomic systems

Mechanism exploration of enhanced electrochemical performance of single-crystal versus polycrystalline LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)

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Rare Metals 2022年第11期41卷 3783-3794页

作者： Tian-Yi Zeng xiao-yun zhang Xing-Yu Qu Mei-Qing Li Pan-Pan zhang Ming-Ru Su Ai-Chun Dou Ahmad Naveed Yu Zhou yun-Jian Liu School of Material Science and Engineering Jiangsu UniversityZhenjiang212013China

Single-crystal LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)(SC-811),which offers better cycle performance compared to the polycrystalline counterpart,has received great *** report herein the synthesis of SC-811 with a grain size of 2-4μm by washing and reheating method,which compares with conventional polycrystalline LiNi_(0.8)-Co_(0.1)Mn_(0.1)O_(2)(PC-811).The discharge capacity of SC-811 reaches 152.1 mAh·g^(-1)after 100 cycles(86.7%capacity retention)at 1.0 C,which is much better than that of PC-811(130.2 mAh·g^(-1),73.8%capacity retention).By using multiscale characterization,the results unveil that SC-811 can not only improve the reversibility of the H2-H3 phase transitions,suppress the generation of micro-cracks and phase transformations,but also mitigate the undesired side reactions between electrode and ***,the Li-O bond of SC-811 is longer than that of PC-811,which is conducive to the de-intercalation of Li-ions,thereby enhancing the structural *** finding provides an impressive strategy to sustain structural stability and improve the cycling life of Ni-rich layered cathodes.

关键词： Li-ion batteries(LIBs) Cathode materials Single-crystal Capacity retention Phase transitions

Effect of iron overload on electrophysiology of slow reaction autorhythmic cells of left ventricular outflow tract in guinea pigs

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Asian Pacific Journal of Tropical Medicine 2018年第2期11卷 151-154页

作者： Ling Fan Li-Feng Chen Jing Fan Lan-Ping Zhao xiao-yun zhang Department of haematology the First Affiliated Hospital of Hebei North University Department of Physiology Basic Medical College Hebei North University Department of Obstetrics and Gynecology the Sixth Hospital of Zhangjiakou

Objective: To investigate the electrophysiology effects and mechanism of iron overload on the slow response autorhythmic cells in the left ventricular outflow tract of guinea ***: Standard microelectrode cell recording techniques were adopted to observe the electrophysiological effects of different concentrations of Fe^(2+)(100 μmol/L, 200 μmol/L) on the left ventricular outflow tract autorhythmic *** tissues were perfused with FeSO_4(200 μmol/L) combing with CaCl_2(4.2 mmol/L), Verapamil,(1 μmol/L), and nickel chloride(200μmol/L) respectively to observe the influences of these contents on electrophysiology of FeSO_4(200μmol/L) on the left ventricular outflow tract autorhythmic ***: Fe^(2+)at both 100 μmol/L and 200 μmol/L could change the electrophysiological parameters of the slow response autorhythmic cells of the left ventricular outflow tract in a concentrationdependent manner resulting into decrease in Vmax, APA and MDP, slower RPF and VDD, and prolonged APD_(50) and APD_(90)(P all <0.05).Besides, perfusion of increased Ca^(2+) concentration could partially offset the electrophysiological effects of Fe^(2+)(200 μmol/L).The L-type calcium channel(LTCC) blocker Verapamil(1 μmol/L) could block the electrophysiological effects of Fe^(2+)(200 μmol/L).But the T-type calcium channel(TTCC) blocker nickel chloride(NiCl_2, 200 μmol/L) could not block the electrophysiological effects of Fe^(2+)(200 μmol/L).Conclusions: Fe^(2+) can directly change the electrophysiological characteristics of the slow response autorhythmic cells of the left ventricular outflow tract probably through the L-type calcium channel.

关键词： Iron overload Iron poisoning Left ventricular outflow tract Slow reaction autorhythmic cell Electrophysiology

Single cell RNA sequencing reveals mesenchymal heterogeneity and critical functions of Cd271 in tooth development

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World Journal of Stem Cells 2023年第6期15卷 589-605页

作者： Yan-Yan zhang Feng Li xiao-Ke Zeng Yan-Hui Zou Bing-Bing Zhu Jia-Jia Ye yun-xiao zhang Qiu Jin Xin Nie School&Hospital of Stomatology Wenzhou Medical UniversityWenzhou 325027Zhejiang ProvinceChina

BACKGROUND Accumulating evidence suggests that the maxillary process,to which cranial crest cells migrate,is essential to tooth *** studies indicate that Cd271 plays an essential role in ***,the underlying mechanisms have yet to be *** To establish the functionally heterogeneous population in the maxillary process,elucidate the effects of Cd271 deficiency on gene expression *** p75NTR knockout(Cd271-/-)mice(from American Jackson laboratory)were used to collect the maxillofacial process tissue of p75NTR knockout mice,and the wildtype maxillofacial process of the same pregnant mouse wild was used as *** single cell suspension,the cDNA was prepared by loading the single cell suspension into the 10x Genomics Chromium system to be sequenced by NovaSeq6000 sequencing ***,the sequencing data in Fastq format were *** FastQC software is used to evaluate the quality of data and CellRanger analyzed the *** gene expression matrix is read by R software,and Seurat is used to control and standardize the data,reduce the dimension and *** search for marker genes for subgroup annotation by consulting literature and database;explore the effect of p75NTR knockout on mesenchymal stem cells(MSCs)gene expression and cell proportion by cell subgrouping,differential gene analysis,enrichment analysis and protein-protein interaction network analysis;understand the interaction between MSCs cells and the differentiation trajectory and gene change characteristics of p75NTR knockout MSCs by cell communication analysis and pseudo-time *** we verified the findings single cell sequencing in *** We identified 21 cell clusters,and we re-clustered these into three ***,we revealed the cell–cell communication networks between *** clarified that Cd271 was significantly associated with the regulation of *** This study provides comprehe

关键词： Cd271 Mesenchymal stem cells Single cell RNA sequencing Osteogenesis Mineralization Tooth development

Contrast-enhanced ultrasound:Improving the preoperative staging of hepatocellular carcinoma and guiding individual treatment

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World Journal of Gastroenterology 2014年第35期20卷 12628-12636页

作者： xiao-yun zhang Yan Luo Tian-Fu Wen Li Jiang Chuan Li xiao-Fei Zhong Jing-Yi zhang Wen-Wu Ling Lu-Nan Yan Yong Zeng Hong Wu Department of Liver Surgery and Liver Transplantation Centre West China Hospital of Sichuan University Department of Sonography West China Hospital of Sichuan University

AIM: To investigate the clinical role of contrast-enhanced ultrasound (CEUS) combined with contrast-enhanced computed tomography (CE-CT) or magnetic resonance imaging to improve the preoperative staging of hepatocellular carcinoma (HCC) and guide surgical decision-making. METHODS: Sixty-nine patients who underwent liver resection for HCC in our center were enrolled prospectively in the study. CEUS and CE-CT/MRI were performed before surgery. Intraoperative ultrasound (IOUS) was carried out after liver mobilization. Lesions depicted by each imaging modality were counted and mapped. To investigate the impact of tumor size on the study, we divided the patients into two groups, the 'Smaller group'(S-group, 5 cm in diameter). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of CE-CT/MRI, CEUS, IOUS, CEUS+CE-CT/MRI and the tumor node metastasis staging of tumors were calculated and compared. Changes in the surgical strategy as a result of CEUS and IOUS were analyzed. RESULTS: One hundred and twenty-seven nodules, comprising 94 HCCs confirmed by histopathology and 33 benign lesions confirmed by histopathology and follow-up, were identified in 69 patients. The overall diagnostic sensitivity rates of CE-CT/MRI, CEUS, IOUS and CEUS+ CE-CT/MRI were 78.7%, 89.4%, 89.4% and 89.4%, respectively. There was a significant difference between CEUS + CE-CT/MRI and CE-CT/MRI (P = 0.046). Combining CEUS with CT or MRI increased, the diagnostic specificity compared with CT/MRI, CEUS and IOUS, and this difference was statistically significant (100%, 72.7%, 97.0%, and 69.7%, P = 0.004, P = 0.002, P = 0.002, respectively). The diagnostic accuracy was significantly higher for CEUS + CT/MRI compared with CT/MRI (92.1% vs 77.2%, P = 0.001). The TNM staging of tumors based on CEUS + CE-CT/MRI approximated to the final pathological TNM staging (P = 0.977). There was a significant difference in t

关键词： Hepatocellular carcinoma Contrast-enhanced ultrasound Tumor node metastasis staging Intraoperative ultrasound Liver resection