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Xiao Y, Tang B, Wu ZH, Ju M, Yang JN. Concentration effects on the local structures and electronic properties of Er xBaY 2-xF 8: a first-principles study. J Phys Condens Matter 2024; 36:325603. [PMID: 38701826 DOI: 10.1088/1361-648x/ad4764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Accepted: 05/03/2024] [Indexed: 05/05/2024]
Abstract
Er3+doped barium yttrium fluoride (BaY2F8) crystal has gained long-term attention due to its great potential in laser and medical device applications. However, the local structures of Er3+doped BaY2F8system (Er:BYF) remain uncertain, and the effect of doping concentration on structures and properties is unknown. Therefore, in this study, the first-principles study of the structural evolution of ErxBaY2-xF8(x= 0.125, 0.25) crystals was carried out. By means of density functional theory and particle swarm optimization algorithm, the stable structures of Er:BYF crystals with two different concentrations are shown as standard monoclinic structures withP2 symmetry for the first time. The impurity Er3+ions successfully enter the main lattice, replacing the Y3+ions, and forming a [ErF8]5-polyhedron withC2point group symmetry. By calculating the electronic properties, the band gap values of the two structures are significantly reduced compared with that of pure BaY2F8crystal. However, the conduction band does not break through the Fermi level, and the crystals still maintain the insulation characteristic. According to the calculation of the electron local density function, we conclude that Er-F and Y-F in Er:BYF are connected by ionic bonds. These results fill a theoretical gap in the study of Er:BYF crystals and provide inspiration for structural evolution and material design at different doping concentrations.
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Affiliation(s)
- Yang Xiao
- School of Sciences, Southwest Petroleum University, Chengdu 610500, People's Republic of China
| | - Bin Tang
- School of Sciences, Southwest Petroleum University, Chengdu 610500, People's Republic of China
| | - Zhen-Hai Wu
- School of Sciences, Southwest Petroleum University, Chengdu 610500, People's Republic of China
| | - Meng Ju
- School of Physical Science and Technology, Southwest University, Chongqing 400715, People's Republic of China
| | - Jin-Ni Yang
- Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, People's Republic of China
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2
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Wang S, Zhong M, Liu H, Ju M. Coexistence of topological node surface and Dirac fermions in phonon-mediated superconductor YB 2C 2. Phys Chem Chem Phys 2024; 26:1454-1461. [PMID: 38113107 DOI: 10.1039/d3cp03678b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2023]
Abstract
The interaction between nontrivial topology and superconductivity in condensed matter physics has attracted tremendous research interest as it could give rise to exotic phenomena. Herein, based on first-principles calculations, we investigate the electronic structures, mechanical properties, topological properties, dynamic stability, electron-phonon coupling (EPC), and superconducting properties of the synthesized real material YB2C2. It is a tetragonal structure with P4/mbm symmetry and exhibits excellent stability. The calculated electronic band structures reveal that a zero-dimension (0D) Dirac point and two-dimensional (2D) nodal surface coexist near the Fermi level. A spin-orbit coupling (SOC) Dirac point with the topological Fermi arc is observed on the (001) surface. These nodal surfaces are protected by a two-fold screw axis and time-reversal symmetry. Based on the Bardeen-Cooper-Schrieffer theory, the superconducting transition temperature (Tc) in the range 1.25-4.45 K with different Coulomb repulsion constant μ* for YB2C2 is estimated to be consistent with previous experimental results. In addition, the EPC is mainly from the coupling between the dx2-y2 and dz2 orbitals of the Y atom and low-energy phonon modes. The presence of superconductivity and nontrivial topological surface state in YB2C2 suggests that it may be a candidate material for topological superconductors.
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Affiliation(s)
- Siqi Wang
- School of Physical Science and Technology, Southwest University, Chongqing 400715, China.
| | - Mingmin Zhong
- School of Physical Science and Technology, Southwest University, Chongqing 400715, China.
| | - Haibo Liu
- School of Physical Science and Technology, Southwest University, Chongqing 400715, China.
| | - Meng Ju
- School of Physical Science and Technology, Southwest University, Chongqing 400715, China.
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3
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Wang P, Liu Q, Liu N, Kuang M, Yang T, Wang B, Ju M, Yuan H, Jiang X, Zhao J. Electric Field-Controlled Magneto-Optical Kerr Effect in A-Type Antiferromagnetic Fe 2CX 2 (X = F, Cl) and Its Janus Monolayer. ACS Appl Mater Interfaces 2023. [PMID: 37916432 DOI: 10.1021/acsami.3c11811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2023]
Abstract
The magneto-optical Kerr effect (MOKE) is a powerful probe of magnetism and has recently gained new attention in antiferromagnetic (AFM) materials. Through extensive first-principles calculations and group theory analysis, we have identified Fe2CX2 (X = F, Cl) and Janus Fe2CFCl monolayers as ideal A-type collinear AFM materials with high magnetic anisotropy and Néel temperatures. By applying a vertical external electrical field (Ef) of 0.2 V/Å, the MOKE is activated for Fe2CF2 and Fe2CCl2 monolayers without changing their magnetic ground state, and the maximum Kerr rotation angles are 0.13 and 0.08°, respectively. Due to the out-of-plane spontaneous polarization, the intrinsic and nonvolatile MOKE is found in the Janus Fe2CFCl monolayer and the maximal Kerr rotation angle without external electronic field is 0.25°. Moreover, the intrinsic built-in electronic field also gives origin to more robust A-type AFM ordering and reversible Kerr angle against external Ef. Our study suggests that Ef is an effective tool for controlling MOKE in two-dimensional (2D) AFM materials. This research opens the possibility of related studies and applications in AFM spintronics.
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Affiliation(s)
- Peng Wang
- Chongqing Key Laboratory of Micro & Nano Structure Optoelectronics, School of Physical Science and Technology, Southwest University, Chongqing 400715, China
| | - Qinxi Liu
- Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, (Dalian University of Technology), Ministry of Education, Dalian 116024, China
| | - Nanshu Liu
- Department of Physics and Beijing Key Laboratory of Optoelectronic Functional Materials & Micro-nano Devices, Renmin University of China, Beijing 100190, China
| | - Minquan Kuang
- Chongqing Key Laboratory of Micro & Nano Structure Optoelectronics, School of Physical Science and Technology, Southwest University, Chongqing 400715, China
| | - Tie Yang
- Chongqing Key Laboratory of Micro & Nano Structure Optoelectronics, School of Physical Science and Technology, Southwest University, Chongqing 400715, China
| | - Biao Wang
- Chongqing Key Laboratory of Micro & Nano Structure Optoelectronics, School of Physical Science and Technology, Southwest University, Chongqing 400715, China
| | - Meng Ju
- Chongqing Key Laboratory of Micro & Nano Structure Optoelectronics, School of Physical Science and Technology, Southwest University, Chongqing 400715, China
| | - Hongkuan Yuan
- Chongqing Key Laboratory of Micro & Nano Structure Optoelectronics, School of Physical Science and Technology, Southwest University, Chongqing 400715, China
| | - Xue Jiang
- Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, (Dalian University of Technology), Ministry of Education, Dalian 116024, China
| | - Jijun Zhao
- Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, (Dalian University of Technology), Ministry of Education, Dalian 116024, China
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4
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Ju M, Yuan H, Ji W, Zhao L, Xiao Y, Yeung Y. Photoluminescence and energy transfer mechanisms of Tm 3+ doped Y 2O 3 laser crystals: experimental and theoretical insights. Phys Chem Chem Phys 2023; 25:25273-25279. [PMID: 37700723 DOI: 10.1039/d3cp03692h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/14/2023]
Abstract
Rare-earth thulium (Tm3+) doped yttrium oxide (Y2O3) host single crystals are promising "eye-safe" laser materials. However, the mechanisms of photoluminescence and energy transfer in Tm3+ doped Y2O3 crystals are not yet understood at the fundamental level. Here, we synthetize a series of Y2O3:Tm3+ samples by the sol-gel method. Our experimental results show that the most intensive absorption line of the 3H6 → 1D2 transition occurs at 358 nm, and the strongest emission line of the 1D2 → 3F4 transition is located at 453 nm, which are in good agreement with the calculations of 363 nm and 458 nm, respectively. By using the CALYPSO structural search method, the ground state structure of Y2O3:Tm3+ with P2 space group symmetry is uncovered. The complete energy levels, including free-ion LS terms and crystal-field LSJ multiplet manifolds, of Y2O3:Tm3+ are obtained based on our developed WEPMD method. The present findings show that our WEPMD method can be used in experiments to elucidate the underlying mechanisms of photoluminescence and energy transfer in Tm3+ doped Y2O3 crystals, which offer insights for further understanding of other rare-earth doped laser materials.
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Affiliation(s)
- Meng Ju
- School of Physical Science and Technology, Southwest University, Chongqing 400715, China.
| | - Hongkuan Yuan
- School of Physical Science and Technology, Southwest University, Chongqing 400715, China.
| | - Wenhao Ji
- School of Physical Science and Technology, Southwest University, Chongqing 400715, China.
| | - Lei Zhao
- School of Physics and Opto-Electronic Technology, Baoji University of Arts and Science, Baoji, Shanxi 721016, China.
| | - Yang Xiao
- School of Sciences, Southwest Petroleum University, Chengdu, 610500, China
| | - Yauyuen Yeung
- Department of Science and Environmental Studies, The Education University of Hong Kong, 10 Lo Ping Road, Tai Po, NT, Hong Kong, China.
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Zhang G, Liu W, Wang L, Ju M, Tian X, Du Z, Kang Z, Zhao J. Genetic Characteristics and Linkage of Virulence Genes of the Puccinia striiformis f. sp. tritici TSA-6 Isolate to Yr5 Host Resistance. Plant Dis 2023; 107:688-700. [PMID: 35869586 DOI: 10.1094/pdis-07-22-1637-re] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
To understand the inheritance of the TSA-6 Puccinia striiformis f. sp. tritici (Pst) isolate that is virulent to Yr5 and was recently detected in China, we analyzed avirulence and virulence of 120 selfed progeny lines from Berberis shensiana. The results showed that the TSA-6 isolate is virulent against the Yr5 resistance gene, and overall progeny lines were categorized into 73 virulence phenotypes (VPs); of these, 72 VPs differed from the isolate TSA-6, and only one VP, including three progeny, was identical to the parental isolate. The analyses indicated that the TSA-6 isolate is homozygous for avirulence at the Yr10, Yr15, and Yr26 resistance loci and virulence at the YrA resistance locus. The TSA-6 isolate is heterozygous for avirulence at the Yr2, Yr3, Yr5, Yr7, and Yr8 resistance loci, which are controlled by a dominant/recessive relationship. The Yr1, Yr6, Yr9, Yr17, Yr27, Yr25, Yr28, Yr29, Yr32, YrTr1, and YrSP resistance loci are governed by two complementary dominant/recessive genes. Avirulence against heterozygous Yr4, Yr43, Yr44, Yr76, and YrExp2 resistance loci is regulated by a dominant and recessive or a dominant and suppressor gene pair. In total, 117 multilocus genotypes were detected at 24 KASP-SNP marker loci among the 120 progenies. Using these marker loci, we constructed a linkage map with a genetic distance interval spanning 624.5 cM. Quantitative trait loci corresponding to phenotypic segregation for virulence at 20 Yr resistance loci in addition to the Yr1 resistance locus were identified. These results facilitate our understanding of Pst virulence evolution and simplify breeding of wheat cultivars with effective resistance to wheat stripe rust.
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Affiliation(s)
- Gensheng Zhang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Wei Liu
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Lin Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Meng Ju
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Xiaxia Tian
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Zhimin Du
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Zhensheng Kang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Jie Zhao
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling 712100, Shaanxi, China
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Jin Y, Huang W, Zhang J, Li S, Cheng S, Sun W, Ju M, Zhang C. An unexpectedly stable Y2B5 compound with the fractional stoichiometry under ambient pressure. ARAB J CHEM 2023. [DOI: 10.1016/j.arabjc.2023.104546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
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7
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Awais M, Zhao J, Cheng X, Ghaffar Khoso A, Ju M, Ur Rehman Z, Iqbal A, Rameez Khan M, Chen W, Liu M, Ma X, Wang L, Liu W, Du Z, Sun M, Zhang G, Kang Z, Ali S. Himalayan mountains imposing a barrier on gene flow of wheat yellow rust pathogen in the bordering regions of Pakistan and China. Fungal Genet Biol 2023; 164:103753. [PMID: 36574524 DOI: 10.1016/j.fgb.2022.103753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 09/18/2022] [Accepted: 11/22/2022] [Indexed: 11/27/2022]
Abstract
The wheat yellow rust pathogen has been shown to be diverse and potentially originated in the Himalayan region. Although Himalayan populations of Pakistan, Nepal and Bhutan have been previously compared, little is known about the relative divergence and diversity in Puccinia striiformis populations in the bordering regions of Pakistan and China. To assess the relative diversity and divergence in these regions of Pakistan (Gilgit-Baltistan, Hazara and Azad Jammu Kashmir) and China (Xinjiang, Qinghai, Tibet, Sichuan, Guizhou and Yunnan), a total of 1245 samples were genotyped using 17 microsatellite SSR markers. A clear divergence was observed between the bordering regions of Pakistan and China (FST = 0.28) without any resampling of genetic groups and multilocus genotypes across two sides of the Himalayan mountains. The closest subpopulations across the two countries were Xinjiang and Gilgit-Baltistan (Nei's distance = 0.147), which were close geographically. A very high diversity and recombinant population structure was observed in both populations, though slightly higher in China (Genotypic diversity = 0.970; r¯d = 0.000) than in Pakistan (Genotypic diversity = 0.902; r¯d = 0.065). The distribution of genetic groups and resampling of MLGs revealed more gene flow across Yunnan, Guizhou and Sichuan regions in China, while between Hazara and Azad-Jammu Kashmir in Pakistan. The lack of gene flow between Pakistan and China populations is due to geographical barriers and a large patch of land without wheat. The information on the relative diversity and divergence in different geographical zones of the pathogen center of diversity and neighboring region should be considered in resistant wheat deployment while considering the invasion potential of the pathogen at regional and global contexts.
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Affiliation(s)
- Muhammad Awais
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, PR China
| | - Jie Zhao
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, PR China.
| | - Xiangrui Cheng
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, PR China
| | - Abdul Ghaffar Khoso
- College of Plant Protection, Dept. Agriculture Entomology & pest control. Northwest A&F University, Yangling, Shaanxi 712100, PR China
| | - Meng Ju
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, PR China
| | - Zia Ur Rehman
- Dept. of Agriculture, Hazara University Mansehra, Pakistan
| | - Aamir Iqbal
- Dept. of Agriculture, Hazara University Mansehra, Pakistan
| | | | - Wen Chen
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, PR China; Guizhou Academy of Agricultural Sciences, Institute of Plant Protection, Guiyang, PR China
| | - Maxinzhi Liu
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, PR China
| | - Xinyao Ma
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, PR China
| | - Lin Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, PR China
| | - Wei Liu
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, PR China
| | - Zhimin Du
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, PR China
| | - Mudi Sun
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, PR China
| | - Gensheng Zhang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, PR China
| | - Zhensheng Kang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, PR China.
| | - Sajid Ali
- Dept. of Agriculture, Hazara University Mansehra, Pakistan.
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Zhang J, Wang Y, Tang L, Duan J, Wang J, Li S, Ju M, Sun W, Jin Y, Zhang C. Exploring high pressure structural transformations, electronic properties and superconducting properties of MH2 (M = Nb, Ta). ARAB J CHEM 2022. [DOI: 10.1016/j.arabjc.2022.104347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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9
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Ju M, Liu W, Wang L, Sun M, Kang Z, Zhao J. Two Main Routes of Spore Migration Contributing to the Occurrence of Wheat Stripe Rust in the Jiangsu and Zhejiang Coastal Sporadic Epidemiological Region in 2019, Based on Phenotyping and Genotyping Analyses. Plant Dis 2022; 106:2948-2957. [PMID: 35365052 DOI: 10.1094/pdis-11-21-2581-re] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici, is a destructive disease in many countries. In China, wheat stripe rust generally occurs in northwestern and southwestern China and sporadically in the Jiangsu and Zhejiang coastal epidemiological region (JZER), where an outbreak of the disease occurred in 2019. To understand the population structure and potential inoculum sources of the pathogen in this region, 171 isolates collected from 93 wheat fields of 53 counties in 10 provinces were phenotyped with two sets of wheat differentials and genotyped with 20 pairs of single-nucleotide polymorphism primers. Phenotype tests indicated that identical races (CYR34, CYR33, Su11-139, and Su11-14-1) detected in Jiangsu and Zhejiang were shared with the oversummering regions (Gansu), overwintering regions (Hubei, Henan, and Shaanxi), and Yun-Gui epidemiological regions (Yunnan and Guizhou). In JZER, races CYR32, G22-14, and G22-68 were detected in Jiangsu, but not in Zhejiang, and Su11-208 was identified in Zhejiang, but not in Jiangsu. Genotypic analysis revealed remarkable gene flows among the Jiangsu, Yunnan, Henan, and Anhui populations, as well as those of Zhejiang, Guizhou, and Sichuan, showing that wheat stripe rust in Zhejiang and Jiangsu was from spores that migrated from different routes. Major gene flows were detected between the Jiangsu and Zhejiang populations. P. striiformis f. sp. tritici from both overwintering regions (Yunnan, Sichuan, Guizhou, Henan, Hubei, and Shaanxi) and oversummering regions (Gansu) contributed to the wheat stripe rust epidemic in the JZER region in 2019.
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Affiliation(s)
- Meng Ju
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Wei Liu
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Lin Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Mudi Sun
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Zhensheng Kang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Jie Zhao
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, China
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Hu L, Chen H, Ju M, Hou A, Xie K, Gao A. Self-Assembled Nanodot Actuator with Changeable Fluorescence by π-π Stacking Force Based on a Four-Armed Foldable Phthalocyanine Molecule and Its Supersensitive Molecular Recognition. Nano Lett 2022; 22:6383-6390. [PMID: 35866680 DOI: 10.1021/acs.nanolett.2c02244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Designing intelligent molecules and smart nanomaterials as molecular machines is becoming increasingly important in the nanoscience fields. Herein, we report a nanodot actuator with changeable fluorescence by π-π stacking force based on a four-armed foldable phthalocyanine molecule. The assembled nanodot possessed a three-dimensional molecular space structure and multiple supramolecular interactions. The arms of the nanodot could fold and open intelligently in response to environmental molecular stimuli such as natural plant mimosa, which could lead to multiple variable fluorescence emissions. The nanodot was highly sensitive to the biomolecule thyroxine at the molecular level. The accurate molecular recognition and the changeable fluorescence conversion of the nanodot were attributed to multiple supramolecular interactions, including photoinduced electron transfer (PET), intramolecular fluorescence resonance energy transfer (FRET), and π-π stacking of the nanodots, resulting in an intelligent "nanodot machine with folding arms". The self-assembled nanodot actuators with changeable fluorescence have potential applications in advanced intelligent material fields.
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Affiliation(s)
- Liu Hu
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Chemistry and Chemical Engineering, Donghua University, Shanghai 201620, P. R. China
- College of Materials and Textiles, Zhejiang Sci-Tech University, Hangzhou 310018, Zhejiang, P R China
| | - Huanghuang Chen
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Chemistry and Chemical Engineering, Donghua University, Shanghai 201620, P. R. China
- National Engineering Research Center for Dyeing and Finishing of Textiles, Donghua University, Shanghai 201620, P R China
| | - Meng Ju
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Chemistry and Chemical Engineering, Donghua University, Shanghai 201620, P. R. China
- National Engineering Research Center for Dyeing and Finishing of Textiles, Donghua University, Shanghai 201620, P R China
| | - Aiqin Hou
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Chemistry and Chemical Engineering, Donghua University, Shanghai 201620, P. R. China
- National Engineering Research Center for Dyeing and Finishing of Textiles, Donghua University, Shanghai 201620, P R China
| | - Kongliang Xie
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Chemistry and Chemical Engineering, Donghua University, Shanghai 201620, P. R. China
| | - Aiqin Gao
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Chemistry and Chemical Engineering, Donghua University, Shanghai 201620, P. R. China
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11
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Awais M, Ali S, Ju M, Liu W, Zhang G, Zhang Z, Li Z, Ma X, Wang L, Du Z, Tian X, Zeng Q, Kang Z, Zhao J. Countrywide inter-epidemic region migration pattern suggests the role of southwestern population in wheat stripe rust epidemics in China. Environ Microbiol 2022; 24:4684-4701. [PMID: 35859329 DOI: 10.1111/1462-2920.16096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Revised: 06/01/2022] [Accepted: 06/04/2022] [Indexed: 11/26/2022]
Abstract
Understanding countrywide pathogen population structure and inter-epidemic region spread is crucial for deciphering crop potential losses. Wheat stripe rust caused by Puccinia striiformis f. sp. tritici is a destructive disease that affects worldwide wheat production, widespread in China, representing largest epidemic region globally. This study aimed to understand the population structure and migration route of P. striiformis f. sp. tritici across China based on sampling from 15 provinces representing six epidemic zones, viz., over-summering, over-wintering, eastern, Yun-Gui, Xinjiang and Tibet epidemic regions. High genotypic diversity was recorded in over-summering, Tibet and over-wintering epidemic regions. Epidemic regions partly explain population subdivision with variable divergence (FST = 0.005-0.344). Xinjiang and Tibet epidemic regions were independent epidemic zones with least sharing of genotypes. Among other epidemic zones, i.e. over-summering, over-wintering, eastern and Yun-Gui epidemic zones, re-sampling MLGs, clustering-based structure, DAPC analyses, relative migration and low divergence (FST from 0.006 to 0.073) revealed frequent geneflow. Yun-Gui epidemic regions, with a potential for both over-summering and over-wintering, could play an important role in causing epidemics in main wheat-cultivating areas of China. High diversity, recombination signatures and inter-epidemic region migration patterns need to be considered in host-resistant cultivar development in China and neighbouring countries, considering risk of long-distance migration capacity of pathogen.
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Affiliation(s)
- Muhammad Awais
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, the People's Republic of China
| | - Sajid Ali
- Department of Agriculture, Hazara University Mansehra, Mansehra, Pakistan
| | - Meng Ju
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, the People's Republic of China
| | - Wei Liu
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, the People's Republic of China
| | - Gensheng Zhang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, the People's Republic of China
| | - Zedong Zhang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, the People's Republic of China
| | - Zejian Li
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, the People's Republic of China
| | - Xinyao Ma
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, the People's Republic of China
| | - Lin Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, the People's Republic of China
| | - Zhimin Du
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, the People's Republic of China
| | - Xiaxia Tian
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, the People's Republic of China
| | - Qingdong Zeng
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, the People's Republic of China
| | - Zhensheng Kang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, the People's Republic of China
| | - Jie Zhao
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, the People's Republic of China
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12
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Chang J, Wu Q, Gao CH, Huang Y, Ju M, Wang G, Yuan H, Chen H. A Hybrid Functional Study on Perovskite-Based Compounds CsPb 1-αZn αI 3-βX β (X = Cl or Br). J Phys Chem Lett 2022; 13:5900-5909. [PMID: 35729749 DOI: 10.1021/acs.jpclett.2c01239] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Inorganic perovskites have attracted a great deal of attention because of their stability. Unfortunately, a weak optical response and the toxicity of lead are hampering their development. Motivated by these facts, we focus herein on the perovskite-based doped series CsPb1-αZnαI3-βXβ (X = Cl or Br). The geometric structures and the electronic and optical properties of CsPb1-αZnαI3-βXβ (X = Cl or Br) are investigated systematically by hybrid functional theory. Analysis of the electronic properties indicates that Zn/Cl/Br mono-doping and co-doping efficiently tune bandgaps. Moreover, we find that the ability to obtain electrons for CsPb0.625Zn0.375I2Cl is superior to the abilities of the others, which implies a stronger electron transition. In addition, CsPb0.625Zn0.375I2Cl and CsPb0.625Zn0.375I2Br show stronger visible-light responses in the range of 467-780 nm. Both CsPb0.625Zn0.375I2Cl and CsPb0.625Zn0.375I2Br are hence good choices for photovoltaic applications. Furthermore, the physically accessible region is also explored herein. These findings shed new light on the design of highly efficient and low-lead perovskite-based optoelectronic materials.
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Affiliation(s)
- Junli Chang
- School of Physical Science and Technology, Chongqing Key Laboratory of Micro & Nano Structure Optoelectronics, Southwest University, Chongqing 400715, People's Republic of China
| | - Qi Wu
- School of Physical Science and Technology, Chongqing Key Laboratory of Micro & Nano Structure Optoelectronics, Southwest University, Chongqing 400715, People's Republic of China
| | - Chun-Hong Gao
- School of Physical Science and Technology, Chongqing Key Laboratory of Micro & Nano Structure Optoelectronics, Southwest University, Chongqing 400715, People's Republic of China
| | - Yuhong Huang
- School of Physical Science and Technology, Chongqing Key Laboratory of Micro & Nano Structure Optoelectronics, Southwest University, Chongqing 400715, People's Republic of China
| | - Meng Ju
- School of Physical Science and Technology, Chongqing Key Laboratory of Micro & Nano Structure Optoelectronics, Southwest University, Chongqing 400715, People's Republic of China
| | - Guangzhao Wang
- Key Laboratory of Extraordinary Bond Engineering and Advanced Materials Technology of Chongqing, School of Electronic Information Engineering, Yangtze Normal University, Chongqing 408100, People's Republic of China
| | - Hongkuan Yuan
- School of Physical Science and Technology, Chongqing Key Laboratory of Micro & Nano Structure Optoelectronics, Southwest University, Chongqing 400715, People's Republic of China
| | - Hong Chen
- School of Physical Science and Technology, Chongqing Key Laboratory of Micro & Nano Structure Optoelectronics, Southwest University, Chongqing 400715, People's Republic of China
- Key Laboratory of Luminescent and Real-Time Analytical Chemistry, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, People's Republic of China
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13
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Lee S, Ju M. The Clinical Outcomes of Marginal Donor Hearts: A Single Center Experience the ‘Margins’ Are Only in Our Mind? J Heart Lung Transplant 2022. [DOI: 10.1016/j.healun.2022.01.1664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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14
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Zhang J, Jin Y, Zhang C, Wang Y, Tang L, Li S, Ju M, Wang J, Sun W, Dou X. The crystal structures, phase stabilities, electronic structures and bonding features of iridium borides from first-principles calculations. RSC Adv 2022; 12:11722-11731. [PMID: 35432946 PMCID: PMC9008517 DOI: 10.1039/d2ra01593e] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 04/08/2022] [Indexed: 01/13/2023] Open
Abstract
We present results of an unbiased structure search for the lowest energy crystalline structures of various stoichiometric iridium borides, using first-principles calculations combined with particle swarm optimization algorithms. As a result, besides three stable phases of C2/m-Ir3B2, Fmm2-Ir4B3, and Cm-Ir4B5, three promising metastable phases, namely, P21/m-Ir2B, P21/m-IrB, and Pnma-Ir3B4, whose energies are within 20 meV per atom above the convex hull curve, are also identified at ambient pressure. The high bulk modulus of 301 GPa, highest shear modulus of 148 GPa, and smallest Poisson's ratio of 0.29 for C2/m-Ir3B2 make it a promising low compressible material. C2/m-Ir3B2 is predicted to possess the highest Vickers hardnesses, with a Vickers hardness of 13.1 GPa and 19.4 GPa based on Chen's model and Mazhnik-Oganov's model respectively, and a high fracture toughness of 5.17 MPa m0.5. The anisotropic indexes and the three-dimensional surface constructions of Young's modulus indicate that Ir–B compounds are anisotropic with the sequence of the elastic anisotropy of Ir2B > IrB > Ir4B5 > Ir3B4 > Ir4B3 > Ir3B2. Remarkably, these iridium borides are all ductile. We further find that the four Ir–B phases of P21/m-Ir2B, C2/m-Ir3B2, P21/m-IrB, and Fmm2-Ir4B3 possess dominant Ir–B covalent bonding character, while strong B–B and Ir–B covalent bonds are present in Cm-Ir4B5 and Pnma-Ir3B4, which are responsible for their excellent mechanical properties. We mainly probe into phase stabilities, structural characters, elastic anisotropy and bonding features of the iridium borides under ambient pressure.![]()
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Affiliation(s)
- Jinquan Zhang
- Department of Physics and Optoelectronic Engineering, Yangtze University, Jingzhou 434023, China
| | - Yuanyuan Jin
- Department of Physics and Optoelectronic Engineering, Yangtze University, Jingzhou 434023, China
| | - Chuanzhao Zhang
- Department of Physics and Optoelectronic Engineering, Yangtze University, Jingzhou 434023, China
| | - Yanqi Wang
- Department of Physics and Optoelectronic Engineering, Yangtze University, Jingzhou 434023, China
| | - Libiao Tang
- Department of Physics and Optoelectronic Engineering, Yangtze University, Jingzhou 434023, China
| | - Song Li
- Department of Physics and Optoelectronic Engineering, Yangtze University, Jingzhou 434023, China
| | - Meng Ju
- School of Physical Science and Technology, Southwest University, Chongqing 400715, China
| | - Jingjing Wang
- College of Computer and Information Engineering, Hubei Normal University, Huangshi 435002, China
| | - Weiguo Sun
- College of Physics and Electronic Information, Luoyang Normal University, Luoyang 471022, China
| | - Xilong Dou
- Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China
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15
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Ju M, Liang H, Zhu Y, Yeung YY, Yuan H, Zhong M, Dai W, Lu C. Insights into the Microstructures and Energy Levels of Pr 3+-Doped YAlO 3 Scintillating Crystals. Inorg Chem 2021; 60:5107-5113. [PMID: 33739095 DOI: 10.1021/acs.inorgchem.1c00021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Trivalent praseodymium (Pr3+)-doped materials have been extensively used in high-resolution laser spectroscopy, owing to their outstanding conversion efficiencies of plentiful transitions in the visible laser region. However, to clarify the microstructure and energy transfer mechanism of Pr3+-doped host crystals is a challenging topic. In this work, the stable structures of Pr3+-doped yttrium orthoaluminate (YAlO3) have been widely searched based on the CALYPSO method. A novel monoclinic structure with the Pm group symmetry is successfully identified. The Pr3+ impurity can precisely occupy the Y3+ position and get incorporated into the YAlO3 (YAP) host crystal with a Pr3+ concentration of 6.25%. The result of the electronic band structure reveals a 3.62 eV band gap, which suggests a semiconductor character of YAP:Pr. Using our developed well-established parametrization matrix diagonalization (WEPMD) method, we have systematically analyzed the energy level scheme and proposed a set of newly improved parameters. Additionally, the energy transfer mechanism of YAP:Pr is clarified by deciphering the numerical electric dipole and magnetic dipole transitions. The popular red emission at 653 nm is assigned to the transition 3P0 → 3F2, while the transition 3P0 → 3H4 with a large branching ratio is predicted to be a good laser channel. Many promising emission lines for laser actions are also obtained in the visible light region. Our results not only provide important insights into the energy transfer mechanisms of rare-earth ion-doped materials but also pave the way for the implementation of new types of laser devices.
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Affiliation(s)
- Meng Ju
- School of Physical Science and Technology, Southwest University, Chongqing 400715, China
| | - Hao Liang
- School of Science, Southwest University of Science and Technology, Mianyang 621010, China
| | - Yongsheng Zhu
- College of Physics and Electronic Engineering, Nanyang Normal University, 1638 Wolong Road, Nanyang 473061, China
| | - Yau-Yuen Yeung
- Department of Science and Environmental Studies, The Education University of Hong Kong, 10 Lo Ping Road, Tai Po, New Territories, Hong Kong, China
| | - Hongkuan Yuan
- School of Physical Science and Technology, Southwest University, Chongqing 400715, China
| | - Mingmin Zhong
- School of Physical Science and Technology, Southwest University, Chongqing 400715, China
| | - Wei Dai
- School of Physics and Mechanical & Electrical Engineering, Hubei University of Education, Wuhan 430205, China
| | - Cheng Lu
- School of Physics and Mechanical & Electrical Engineering, Hubei University of Education, Wuhan 430205, China
- School of Mathematics and Physics, China University of Geosciences (Wuhan), Wuhan 430074, China
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16
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Xiao Y, Kuang X, Yeung Y, Ju M. Unraveling the local structure and luminescence evolution in Nd 3+-doped LiYF 4: a new theoretical approach. Phys Chem Chem Phys 2020; 22:21074-21082. [PMID: 32940295 DOI: 10.1039/d0cp03748f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Neodymium ion (Nd3+)-doped yttrium lithium fluoride (LiYF4, YLF) laser crystals have shown significant prospects as excellent laser materials in many kinds of solid-state laser systems. However, the origins of the detailed information of their local structure and luminescence evolution are still poorly understood. Herein, we use an unbiased CALYPSO structure searching technique and density functional theory to study the local structure of Nd3+-doped YLF. Our results reveal a new stable phase with the P4[combining macron] (No. 81) space group for Nd3+-doped YLF, indicating that the host Y3+ ion site was naturally occupied by the Nd3+ ion impurity. On the basis of our newly developed WEPMD method, we adopt a specific type of orthogonal correlation crystal field to obtain a new set of crystal-field parameters as well as 182 complete Stark energy levels. Many absorption and emission lines for Nd3+-doped YLF are calculated and discussed based on Judd-Ofelt theory, and our results indicate that some of the observed absorption and emission lines are perfectly reproduced by our theoretical calculations. Additionally, we predict several promising transition lines in the visible and near-infrared spectral regions, including the electronic dipole emission lines 4F5/2 → 4I9/2 at 808 nm and 2H9/2 → 4I9/2 at 799 nm, as well as the magnetic dipole emission lines 4F3/2(27) → 4I11/2(6) at 1047 nm and 4F3/2(27) → 4I11/2(8) at 1052 nm. These transition channels indicate that Nd3+-doped YLF laser crystals have greatly promising laser actions for serving as a solid-state laser material.
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Affiliation(s)
- Yang Xiao
- Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China.
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17
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Ju M, Wang J, Huang J, Zhang C, Jin Y, Sun W, Li S, Chen Y. The Microstructure and Electronic Properties of Yttrium Oxide Doped With Cerium: A Theoretical Insight. Front Chem 2020; 8:338. [PMID: 32411670 PMCID: PMC7198891 DOI: 10.3389/fchem.2020.00338] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Accepted: 04/01/2020] [Indexed: 11/13/2022] Open
Abstract
Trivalent Cerium (Ce3+) doped Yttrium Oxide (Y2O3) host crystal has drawn considerable interest due to its popular optical 5d-4f transition. The outstanding optical properties of Y2O3:Ce system have been demonstrated by previous studies but the microstructures still remain unclear. The lacks of Y2O3:Ce microstructures could constitute a problem to further exploit its potential applications. In this sense, we have comprehensively investigated the structural evolutions of Y2O3:Ce crystals based on the CALYPSO structure search method in conjunction with density functional theory calculations. Our result uncovers a new rhombohedral phase of Y2O3:Ce with R-3 group symmetry. In the host crystal, the Y3+ ion at central site can be naturally replaced by the doped Ce3+, resulting in a perfect cage-like configuration. We find an interesting phase transition that the crystallographic symmetry of Y2O3 changes from cubic to rhombohedral when the impurity Ce3+ is doped into the host crystal. With the nominal concentration of Ce3+ at 3.125%, many metastable structures are also identified due to the different occupying points in the host crystal. The X-ray diffraction patterns of Y2O3:Ce are simulated and the theoretical result is comparable to experimental data, thus demonstrating the validity of the lowest energy structure. The result of phonon dispersions shows that the ground state structure is dynamically stable. The analysis of electronic properties indicate that the Y2O3:Ce possesses a band gap of 4.20 eV which suggests that the incorporation of impurity Ce3+ ion into Y2O3 host crystal leads to an insulator to semiconductor transition. Meanwhile, the strong covalent bonds of O atoms in the crystal, which may greatly contribute to the stability of ground state structure, are evidenced by electron localization function. These obtained results elucidate the structural and bonding characters of Y2O3:Ce and could also provide useful insights for understanding the experimental phenomena.
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Affiliation(s)
- Meng Ju
- School of Physical Science and Technology, Southwest University, Chongqing, China.,College of Computer and Information Engineering, Hubei Normal University, Huangshi, China
| | - Jingjing Wang
- College of Computer and Information Engineering, Hubei Normal University, Huangshi, China
| | - Jing Huang
- School of Physical Science and Technology, Southwest University, Chongqing, China
| | - Chuanzhao Zhang
- Department of Physics and Optoelectronic Engineering, Yangtze University, Jingzhou, China
| | - Yuanyuan Jin
- Department of Physics and Optoelectronic Engineering, Yangtze University, Jingzhou, China
| | - Weiguo Sun
- Centre for Science at Extreme Conditions and School of Physics and Astronomy, Scottish Universities Physics Alliance (SUPA), University of Edinburgh, Edinburgh, United Kingdom
| | - Shichang Li
- School of Science, Chongqing University of Posts and Telecommunications, Chongqing, China
| | - Yunhong Chen
- College of Computer and Information Engineering, Hubei Normal University, Huangshi, China
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18
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Lee S, Ju M, Kim J. Back Flow Arteriovenous Shunt Test for Weaning of Venoarterial Extracorporeal Membrane Oxygenator. J Heart Lung Transplant 2020. [DOI: 10.1016/j.healun.2020.01.954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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19
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Ju M, Pan L, Zhang C, Jin Y, Zhong M, Li S, Li S, Yang T, Wang X. The geometrical structure and electronic properties of trivalent Ho 3+ doped Y 2O 3 crystals: a first-principles study. RSC Adv 2020; 10:28674-28679. [PMID: 35520077 PMCID: PMC9055865 DOI: 10.1039/d0ra05188h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 07/29/2020] [Indexed: 11/21/2022] Open
Abstract
Trivalent rare-earth holmium ion (Ho3+) doped yttrium oxide (Y2O3) has attracted great research interest owing to its unique optoelectronic properties and excellent performances in many new-type laser devices. But the crystal structures of the Ho3+-doped Y2O3 system (Y2O3 : Ho) are still unclear. Here, we have carried out a first-principle study on the structural evolution of the trivalent Ho3+ doped Y2O3 by using the CALYPSO structure search method. The results indicate that the lowest-energy structure of Ho3+-doped Y2O3 possesses a standardized monoclinic P2 phase. It is found that the doped Ho3+ ion are likely to occupy the sites of Y3+ in the host crystal lattice, forming the [HoO6]9− local structure with C2 site symmetry. Electronic structure calculations reveal that the band gap value of Ho3+-doped Y2O3 is approximately 4.27 eV, suggesting the insulating character of Y2O3 : Ho system. These findings could provide fundamental insights to understand the atomic interactions in crystals as well as the information of electronic properties for other rare-earth-doped materials. Our study successfully identified the ground-state structure of Ho3+-doped Y2O3 crystal for the first time.![]()
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Affiliation(s)
- Meng Ju
- School of Physical Science and Technology
- Southwest University
- Chongqing 400715
- China
- Department of Physics and Optoelectronic Engineering
| | - Lu Pan
- School of Physical Science and Technology
- Southwest University
- Chongqing 400715
- China
| | - Chuanzhao Zhang
- Department of Physics and Optoelectronic Engineering
- Yangtze University
- Jingzhou 434023
- China
| | - Yuanyuan Jin
- Department of Physics and Optoelectronic Engineering
- Yangtze University
- Jingzhou 434023
- China
| | - Mingmin Zhong
- School of Physical Science and Technology
- Southwest University
- Chongqing 400715
- China
| | - Song Li
- Department of Physics and Optoelectronic Engineering
- Yangtze University
- Jingzhou 434023
- China
| | - Shichang Li
- School of Science
- Chongqing University of Posts and Telecommunications
- Chongqing 400065
- China
| | - Tie Yang
- School of Physical Science and Technology
- Southwest University
- Chongqing 400715
- China
| | - Xiaotian Wang
- School of Physical Science and Technology
- Southwest University
- Chongqing 400715
- China
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20
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Xiao Y, Kuang X, Yeung Y, Ju M. Investigation of the Structure and Luminescence Mechanism of Tm3+-Doped LiYF4: New Theoretical Perspectives. Inorg Chem 2019; 59:1211-1217. [DOI: 10.1021/acs.inorgchem.9b02935] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yang Xiao
- Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China
| | - Xiaoyu Kuang
- Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China
| | - Yauyuen Yeung
- Department of Science and Environmental Studies, The Education University of Hong Kong, 10 Lo Ping Road, Tai Po, New Territories, Hong Kong, China
| | - Meng Ju
- School of Physical Science and Technology, Southwest University, Chongqing 400715, China
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21
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Ju M, Xiao Y, Zhong M, Sun W, Xia X, Yeung YY, Lu C. New Theoretical Insights into the Crystal-Field Splitting and Transition Mechanism for Nd 3+-Doped Y 3Al 5O 12. ACS Appl Mater Interfaces 2019; 11:10745-10750. [PMID: 30789696 DOI: 10.1021/acsami.9b00973] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
There has been considerable research interest paid to rare-earth transition-metal-doped Y3Al5O12, which has great potential for application as a laser crystal of new-type laser devices because of its unique optoelectronic and photophysical properties. Here, we present new research conducted on the structural evolution and crystal-field characteristics of a rare-earth Nd-doped Y3Al5O12 laser crystal by using the CALYPSO structure search method and our newly developed WEPMD method. A novel cage-like structure with a Nd3+ concentration of 4.16% is uncovered, which belongs to the standardized C222 space group. Our results indicate that the impurity Nd3+ ions are likely to substitute the Y3+ at the central site of the host Y3Al5O12 crystal lattice. The laser emission 4F3/2 → 4I11/2 occurring at 1077 nm is in accord with that of the experimental data. By introducing the proper correlation crystal field, three transitions, 4G5/2 → 4I9/2, 4F7/2 → 4I9/2, and 4S3/2 → 4I9/2, are predicted to be good candidates for laser action. These findings can provide powerful guidelines for further experiments of rare-earth-metal-doped laser crystals.
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Affiliation(s)
- Meng Ju
- School of Physical Science and Technology , Southwest University , Chongqing 400715 , China
| | - Yang Xiao
- Department of Physics , Nanyang Normal University , Nanyang 473061 , China
- Institute of Atomic and Molecular Physics , Sichuan University , Chengdu 610065 , China
| | - MingMin Zhong
- School of Physical Science and Technology , Southwest University , Chongqing 400715 , China
| | - Weiguo Sun
- Institute of Atomic and Molecular Physics , Sichuan University , Chengdu 610065 , China
| | - Xinxin Xia
- Institute of Atomic and Molecular Physics , Sichuan University , Chengdu 610065 , China
| | - Yau-Yuen Yeung
- Department of Science and Environmental Studies , The Education University of Hong Kong , Tai Po, New Territories, Hong Kong , China
| | - Cheng Lu
- Department of Physics , Nanyang Normal University , Nanyang 473061 , China
- School of Science , Northwestern Polytechnic University , Xi'an 710072 , China
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22
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Marar M, Gabriel P, Hwang W, Owen D, Ju M, Simone C, Christodouleas J, Vapiwala N, Berman A. Acute Hospital Encounters in Cancer Patients Treated with Definitive Radiation Therapy. Int J Radiat Oncol Biol Phys 2018. [DOI: 10.1016/j.ijrobp.2018.07.1226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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23
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Abstract
Thulium-doped yttrium aluminum garnet (Tm:YAG) is an important solid-state laser crystal. The energy-level splitting within it is still an unresolved problem. Here, we perform a theoretical study on the microstructure of Tm3+-doped YAG using the CALYPSO structure search method in conjunction with first-principles calculations. The calculated results show that the 4.16% doping concentration of Tm3+ impurity causes an obvious structural distortion of YAG crystal, forming an orthorhombic phase in C222 symmetry. On the basis of our developed WEPMD method, we obtain a new and complete set of free-ion and crystal field parameters by a good fit (with proper irreducible representations) to 69 observed energy levels and determine the exact energy-level splitting of Tm3+ in YAG. The calculated Stark levels and electric dipole transitions are in excellent agreement with the measured data and similar theoretical calculations. Some promising emission lines between 3F3, 3F2, 1D2, and 1I6 states are presented. These findings offer fundamental insights and practical tools for further exploration of the structural and electronic properties of other transition-metal-doped YAG crystal.
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Affiliation(s)
- Meng Ju
- School of Physical Science and Technology , Southwest University , Chongqing 400715 , China
| | - MingMin Zhong
- School of Physical Science and Technology , Southwest University , Chongqing 400715 , China
| | - Cheng Lu
- Department of Physics , Nanyang Normal University , Nanyang 473061 , China.,Department of Physics and High Pressure Science and Engineering Center , University of Nevada , Las Vegas , Nevada 89154 , United States
| | - Yau-Yuen Yeung
- Department of Science and Environmental Studies , The Education University of Hong Kong , Tai Po, NT , Hong Kong , China
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24
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Tu G, He H, Yin K, Ju M, Zheng Y, Zhu D, Luo Z. High-flow Nasal Cannula Versus Noninvasive Ventilation for Treatment of Acute Hypoxemic Respiratory Failure in Renal Transplant Recipients. Transplant Proc 2017; 49:1325-1330. [PMID: 28736002 DOI: 10.1016/j.transproceed.2017.03.088] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2016] [Revised: 02/23/2017] [Accepted: 03/15/2017] [Indexed: 02/07/2023]
Abstract
OBJECTIVE This study aimed to evaluate the outcomes of high-flow nasal cannula (HFNC) oxygen therapy compared with noninvasive ventilation (NIV) for the treatment of acute hypoxemic respiratory failure in renal transplant recipients. METHODS Data were retrospectively collected from a tertiary intensive care unit (ICU) from July 1, 2011, to September 31, 2015. All renal recipients who had acute respiratory failure at that period of time were classified into the HFNC or NIV group depending on the initial form of respiratory support. RESULTS A total of 38 patients were enrolled in this study. Twenty patients received HFNC and the other 18 received NIV as the initial respiratory support. The ICU mortality in the HFNC group was 5% (1 patient), compared with 22.2% (4 patients) in the NIV group (P = .083). The median length of the ICU stay was 12 days in the HFNC group, compared with 14 days in the NIV group (P = .297). The number of ventilator-free days at day 28 was significantly higher in the HFNC group than in the NIV group (26 ± 3 vs 21 ± 3; P < .001). The incidences of both pneumothorax (0% vs 22.2%; P = .042) and skin breakdown (0% vs 22.2%; P = .042) were significantly lower in the HFNC group. CONCLUSIONS In renal transplant recipients with acute hypoxemic respiratory failure secondary to severe pneumonia, HFNC achieved outcomes similar to NIV. In addition, HFNC was associated with an increased number of ventilator-free days at day 28 and fewer complications.
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Affiliation(s)
- G Tu
- Department of Critical Care Medicine, Zhongshan Hospital, Fudan University, Shanghai, People's Republic of China
| | - H He
- Department of Critical Care Medicine, Zhongshan Hospital, Fudan University, Shanghai, People's Republic of China
| | - K Yin
- Department of Cardiac Surgery, Zhongshan Hospital, Fudan University, Shanghai, People's Republic of China
| | - M Ju
- Department of Critical Care Medicine, Zhongshan Hospital, Fudan University, Shanghai, People's Republic of China
| | - Y Zheng
- Department of Critical Care Medicine, Zhongshan Hospital, Fudan University, Shanghai, People's Republic of China
| | - D Zhu
- Department of Critical Care Medicine, Zhongshan Hospital, Fudan University, Shanghai, People's Republic of China.
| | - Z Luo
- Department of Critical Care Medicine, Zhongshan Hospital, Fudan University, Shanghai, People's Republic of China
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Ju M, Lu C, Yeung Y, Kuang X, Wang J, Zhu Y. Structural Evolutions and Crystal Field Characterizations of Tm-Doped YAlO 3: New Theoretical Insights. ACS Appl Mater Interfaces 2016; 8:30422-30429. [PMID: 27734663 DOI: 10.1021/acsami.6b09079] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The recent renaissance of the use of rare-earth-doped yttrium orthoaluminate as an ideal laser material has generated significant interest; however, the unique structural features underlying many of its outstanding optical properties still require elucidation. To solve this intriguing problem, we performed a systematic first-principles study; the results of the study reveal a new stable phase for Tm3+-doped YAlO3 (YAP), of monoclinic Pm symmetry, with an 80-atom per unit cell. An unbiased CALYPSO structure search indicates that the Tm3+ impurity ion tends to substitute the position of Y3+ in the YAP crystal lattice. Electronic band structure calculations reveal that the insulated behaviors of YAP are significantly eliminated after doping the impure Tm3+ ions, as evidenced by the minor energy gap of about 0.4 eV, which is close to the band gap energy of a 2 μm emitter source. On the basis of our developed crystal-field theory method, the 4f12 electronic structures and energies of Tm3+ ions in the YAP crystal are calculated. The theoretical results indicate that the electric-dipole-induced transition 3H4 → 3H5 is mainly responsible for producing the light wave at approximately 2.3 μm. The present results provide an essential understanding of the rare-earth-ion-doped lasing materials and serve as a practical tool for further exploration of such materials.
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Affiliation(s)
- Meng Ju
- Institute of Atomic and Molecular Physics, Sichuan University , Chengdu 610065, China
- Department of Physics, Nanyang Normal University , Nanyang 473061, China
| | - Cheng Lu
- Department of Physics, Nanyang Normal University , Nanyang 473061, China
| | - Yauyuen Yeung
- Department of Science and Environmental Studies, The Education University of Hong Kong , 10 Lo Ping Road, Tai Po, NT, Hong Kong, China
| | - Xiaoyu Kuang
- Institute of Atomic and Molecular Physics, Sichuan University , Chengdu 610065, China
| | - Jingjing Wang
- Institute of Atomic and Molecular Physics, Sichuan University , Chengdu 610065, China
| | - Yongsheng Zhu
- Department of Physics, Nanyang Normal University , Nanyang 473061, China
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Li CG, Sun HJ, Ren BZ, Tang YN, Ju M. Systematic theoretical investigation of structure and electronic properties of pure copper and lithium doped copper clusters. Mol Phys 2016. [DOI: 10.1080/00268976.2016.1143125] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Cheng-Gang Li
- School of Chemical Engineering and Energy, Zhengzhou University, Zhengzhou, China
- School of Physics and Electronic Engineering, Quantum Materials Research Center, Zhengzhou Normal University, Zhengzhou, China
| | - Hai-Jie Sun
- Department of Chemistry, Institute of Environmental and Catalytic Engineering, Zhengzhou Normal University, Zhengzhou, China
| | - Bao-Zeng Ren
- School of Chemical Engineering and Energy, Zhengzhou University, Zhengzhou, China
| | - Ya-Nan Tang
- School of Physics and Electronic Engineering, Quantum Materials Research Center, Zhengzhou Normal University, Zhengzhou, China
| | - Meng Ju
- Institute of Atomic and Molecular Physics, Sichuan University, Chengdu, China
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Xing X, Hermann A, Kuang X, Ju M, Lu C, Jin Y, Xia X, Maroulis G. Insights into the geometries, electronic and magnetic properties of neutral and charged palladium clusters. Sci Rep 2016; 6:19656. [PMID: 26794267 PMCID: PMC4726383 DOI: 10.1038/srep19656] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Accepted: 12/16/2015] [Indexed: 12/26/2022] Open
Abstract
We performed an unbiased structure search for low-lying energetic minima of neutral and charged palladium PdnQ (n = 2–20, Q = 0, + 1 and –1) clusters using CALYPSO method in combination with density functional theory (DFT) calculations. The main candidates for the lowest energy neutral, cationic and anionic clusters are identified, and several new candidate structures for the cationic and anionic ground states are obtained. It is found that the ground state structures of small palladium clusters are more sensitive to the charge states. For the medium size Pdn0/+/– (n = 16–20) clusters, a fcc-like growth behavior is found. The structural transition from bilayer-like structures to cage-like structures is likely to occur at n = 14 for the neutral and cationic clusters. In contrast, for the anionic counterparts, the structural transition occurs at Pd13–. The photoelectron spectra (PES) of palladium clusters are simulated based on the time-dependent density functional theory (TD-DFT) method and compared with the experimental data. The good agreement between the experimental PES and simulated spectra provides us unequivocal structural information to fully solve the global minimum structures, allowing for new molecular insights into the chemical interactions in the Pd cages.
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Affiliation(s)
- Xiaodong Xing
- Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China.,Department of Physics, Nanyang Normal University, Nanyang 473061, China
| | - Andreas Hermann
- Centre for Science at Extreme Conditions and SUPA, School of Physics and Astronomy, The University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - Xiaoyu Kuang
- Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China
| | - Meng Ju
- Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China
| | - Cheng Lu
- Department of Physics, Nanyang Normal University, Nanyang 473061, China.,Beijing Computational Science Research Center, Beijing 100084, China
| | - Yuanyuan Jin
- Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China
| | - Xinxin Xia
- Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China
| | - George Maroulis
- Department of Chemistry, University of Patras, GR-26500 Patras, Greece
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Jin Y, Tian Y, Kuang X, Zhang C, Lu C, Wang J, Lv J, Ding L, Ju M. Ab Initio Search for Global Minimum Structures of Pure and Boron Doped Silver Clusters. J Phys Chem A 2015; 119:6738-45. [DOI: 10.1021/acs.jpca.5b03542] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yuanyuan Jin
- Institute
of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China
| | - Yonghong Tian
- Department
of Physics and Optoelectronic Engineering, Yangtze University, Jingzhou 434023, China
| | - Xiaoyu Kuang
- Institute
of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China
| | - Chuanzhao Zhang
- Institute
of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China
| | - Cheng Lu
- Department
of Physics, Nanyang Normal University, Nanyang 473061, China
| | - Jingjing Wang
- Institute
of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China
| | - Jian Lv
- Beijing Computational Science Research Center, Beijing 100084, China
| | - Liping Ding
- Institute
of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China
| | - Meng Ju
- Institute
of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China
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Jin Y, Maroulis G, Kuang X, Ding L, Lu C, Wang J, Lv J, Zhang C, Ju M. Geometries, stabilities and fragmental channels of neutral and charged sulfur clusters: SnQ(n = 3–20, Q = 0, ±1). Phys Chem Chem Phys 2015; 17:13590-7. [DOI: 10.1039/c5cp00728c] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
We have performed unbiased searches for the global minimum structures of neutral and charged sulfur clusters relying on the CALYPSO method combined with DFT geometric optimization.
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Affiliation(s)
- Yuanyuan Jin
- Institute of Atomic and Molecular Physics
- Sichuan University
- Chengdu 610065
- China
| | - George Maroulis
- Department of Chemistry
- University of Patras
- GR-26500 Patras
- Greece
| | - Xiaoyu Kuang
- Institute of Atomic and Molecular Physics
- Sichuan University
- Chengdu 610065
- China
| | - Liping Ding
- Institute of Atomic and Molecular Physics
- Sichuan University
- Chengdu 610065
- China
| | - Cheng Lu
- Department of Physics
- Nanyang Normal University
- Nanyang 473061
- China
| | - Jingjing Wang
- Institute of Atomic and Molecular Physics
- Sichuan University
- Chengdu 610065
- China
| | - Jian Lv
- State Key Laboratory of Superhard Materials
- Jilin University
- Changchun 130012
- China
- Beijing Computational Science Research Center
| | - Chuanzhao Zhang
- Institute of Atomic and Molecular Physics
- Sichuan University
- Chengdu 610065
- China
| | - Meng Ju
- Institute of Atomic and Molecular Physics
- Sichuan University
- Chengdu 610065
- China
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Wang JJ, Hermann A, Kuang XY, Jin YY, Lu C, Zhang CZ, Ju M, Si MT, Iitaka T. Exploration of stable stoichiometries, physical properties and hardness in the Rh–Si system: a first-principles study. RSC Adv 2015. [DOI: 10.1039/c5ra08476h] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Exploration of stable stoichiometries of the Rh–Si system.
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Affiliation(s)
- Jing-Jing Wang
- Institute of Atomic and Molecular Physics
- Sichuan University
- Chengdu
- China
| | - Andreas Hermann
- Centre for Science at Extreme Conditions and SUPA
- School of Physics and Astronomy
- The University of Edinburgh
- Edinburgh EH9 3JZ
- UK
| | - Xiao-Yu Kuang
- Institute of Atomic and Molecular Physics
- Sichuan University
- Chengdu
- China
| | - Yuan-Yuan Jin
- Institute of Atomic and Molecular Physics
- Sichuan University
- Chengdu
- China
| | - Cheng Lu
- Department of Physics
- Nanyang Normal University
- Nanyang
- China
| | - Chuan-Zhao Zhang
- Institute of Atomic and Molecular Physics
- Sichuan University
- Chengdu
- China
| | - Meng Ju
- Institute of Atomic and Molecular Physics
- Sichuan University
- Chengdu
- China
| | - Meng-Ting Si
- Department of Physics
- Nanyang Normal University
- Nanyang
- China
| | - Toshiaki Iitaka
- Computational Astrophysics Laboratory
- RIKEN (The Institute of Physical and Chemical Research) 2-1 Hirosawa
- Wako
- Japan
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31
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Ju M, Lv J, Kuang XY, Ding LP, Lu C, Wang JJ, Jin YY, Maroulis G. Systematic theoretical investigation of geometries, stabilities and magnetic properties of iron oxide clusters (FeO)nμ(n = 1–8, μ = 0, ±1): insights and perspectives. RSC Adv 2015. [DOI: 10.1039/c4ra12259c] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The structural and magnetic properties of neutral and charged (FeO)nμ(n= 1–8,μ= 0, ±1) clusters have been studied using an unbiased CALYPSO structure searching method.
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Affiliation(s)
- Meng Ju
- Institute of Atomic and Molecular Physics
- Sichuan University
- Chengdu 610065
- China
| | - Jian Lv
- Beijing Computational Science Research Center
- Beijing 100084
- China
- State Key Laboratory of Superhard Materials
- Jilin University
| | - Xiao-Yu Kuang
- Institute of Atomic and Molecular Physics
- Sichuan University
- Chengdu 610065
- China
| | - Li-Ping Ding
- Institute of Atomic and Molecular Physics
- Sichuan University
- Chengdu 610065
- China
| | - Cheng Lu
- Department of Physics
- Nanyang Normal University
- Nanyang 473061
- China
| | - Jing-Jing Wang
- Institute of Atomic and Molecular Physics
- Sichuan University
- Chengdu 610065
- China
| | - Yuan-Yuan Jin
- Institute of Atomic and Molecular Physics
- Sichuan University
- Chengdu 610065
- China
| | - George Maroulis
- Department of Chemistry
- University of Patras
- GR-26500 Patras
- Greece
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Ju M, Kao G, Steinmetz D, Patsch D, Alonso-Basanta M, Hahn S, Lustig R, Dorsey J. A Circulating Tumor Cell Assay for Tracking Treatment Response in Glioma. Int J Radiat Oncol Biol Phys 2014. [DOI: 10.1016/j.ijrobp.2014.05.738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Rajaram R, Ju M, Ko C, Bilimoria K, Decamp M. O-032 * PREDICTORS AND REASONS FOR READMISSION AFTER PULMONARY RESECTION. Interact Cardiovasc Thorac Surg 2014. [DOI: 10.1093/icvts/ivu167.32] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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34
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Abstract
This article reviews numerical simulations of red blood cells (RBCs) mainly using the lattice Boltzmann method (LBM), focusing on the 2-dimensional deformation and aggregation of the cells in simple shear flow. We outline the incorporation of the immersed boundary method into the LBM, in which the membrane forces are obtained from the membrane model. The RBCs are simulated as a single biconcave capsule and as a doublet of biconcave capsules. The transition from swinging to tumbling motions of the RBCs, as induced by reducing the shear rate or increasing the membrane bending stiffness, is discussed. Also discussed is the aggregation tendency of the doublet of RBCs, for which homogenous deformability maintained RBC aggregation, whereas an increased deformability difference resulted in RBC dissociation.
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Affiliation(s)
- Hong-Tong Low
- Division of Bioengineering, Department of Mechanical Engineering, National University of Singapore, Singapore 117576
| | - M Ju
- Department of Biomedical Engineering, National University of Singapore, Singapore
| | - Y Sui
- School of Engineering and Materials Science, Queen Mary University of London, London, United Kingdom
| | - T Nazir
- Department of Mechanical Engineering, National University of Singapore, Singapore
| | - B Namgung
- Department of Biomedical Engineering, National University of Singapore, Singapore
| | - Sangho Kim
- Department of Bioengineering, National University of Singapore, Singapore 117575
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Shi J, Ju M, Large WA, Albert AP. Pharmacological profile of phosphatidylinositol 3-kinases and related phosphatidylinositols mediating endothelin(A) receptor-operated native TRPC channels in rabbit coronary artery myocytes. Br J Pharmacol 2012; 166:2161-75. [PMID: 22404177 PMCID: PMC3402779 DOI: 10.1111/j.1476-5381.2012.01937.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Revised: 01/27/2012] [Accepted: 02/20/2012] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND AND PURPOSE Endothelin(A) (ET(A) ) receptor-operated canonical transient receptor potential (TRPC) channels mediate Ca²⁺ influx pathways, which are important in coronary artery function. Biochemical pathways linking ET(A) receptor stimulation to TRPC channel opening are unknown. We investigated the involvement of phosphatidylinositol 3-kinases (PI3K) in ET(A) receptor activation of native heteromeric TRPC1/C5/C6 and TRPC3/C7 channels in rabbit coronary artery vascular smooth muscle cells (VSMCs). EXPERIMENTAL APPROACH A pharmacological profile of PI3K was created by studying the effect of pan-PI3K, pan-Class I PI3K and Class I PI3K isoform-selective inhibitors on ET(A) receptor-evoked single TRPC1/C5/C6 and TRPC3/C7 channel activities in cell-attached patches from rabbit freshly isolated coronary artery VSMCs. The action of phosphatidylinositol 3-phosphate- [PI(3)P], 4-phosphate- [PI(4)P] and 5-phosphate- [PI(5)P] containing molecules involved in PI3K-mediated reactions were studied in inside-out patches. Expression of PI3K family members in coronary artery tissue lysates were analysed using quantitative PCR. KEY RESULTS ET(A) receptor-operated TRPC1/C5/C6 and TRPC3/C7 channel activities were inhibited by wortmannin. However, ZSTK474 and AS252424 reduced ET(A) receptor-evoked TRPC1/C5/C6 channel activity but potentiated TRPC3/C7 channel activity. All the PI(3)P-, PI(4)P- and PI(5)P-containing molecules tested induced TRPC1/C5/C6 channel activation, whereas only PI(3)P stimulated TRPC3/C7 channels. CONCLUSIONS AND IMPLICATIONS ET(A) receptor-operated native TRPC1/C5/C6 and TRPC3/C7 channel activities are likely to be mediated by Class I PI3Kγ and Class II/III PI3K isoforms, respectively. ET(A) receptor-evoked and constitutively active PI3Kγ-mediated pathways inhibit TRPC3/C7 channel activation. PI3K-mediated pathways are novel regulators of native TRPC channels in VSMCs, and these signalling cascades are potential pharmacological targets for coronary artery disease.
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Affiliation(s)
- J Shi
- Pharmacology & Cell Physiology, Division of Biomedical Sciences, St. George's, University of London, London, UK
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36
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Chung H, Shin J, Ju M. Increased Surfactant Protein-D In Young Infants With Bronchiolitis. J Allergy Clin Immunol 2011. [DOI: 10.1016/j.jaci.2010.12.105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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37
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Craft J, Oh J, Ju M, Bradley J, Deasy J, El Naqa I. Quantitative Mass Spectroscopy and the Identification of Alpha2macroglobulin as a Potential Biomarker for Radiation Pneumonitis. Int J Radiat Oncol Biol Phys 2010. [DOI: 10.1016/j.ijrobp.2010.07.1166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Shi J, Ju M, Saleh SN, Albert AP, Large WA. TRPC6 channels stimulated by angiotensin II are inhibited by TRPC1/C5 channel activity through a Ca2+- and PKC-dependent mechanism in native vascular myocytes. J Physiol 2010; 588:3671-82. [PMID: 20660561 DOI: 10.1113/jphysiol.2010.194621] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The present work investigated interactions between TRPC1/C5 and TRPC6 cation channel activities evoked by angiotensin II (Ang II) in native rabbit mesenteric artery vascular smooth muscle cells (VSMCs). In low intracellular Ca(2+) buffering conditions (0.1 mm BAPTA), 1 nm and 10 nm Ang II activated both 2 pS TRPC1/C5 channels and 15-45 pS TRPC6 channels in the same outside-out patches. However, increasing Ang II to 100 nm abolished TRPC6 activity but further increased TRPC1/C5 channel activity. Comparison of individual patches revealed an inverse relationship between TRPC1/C5 and TRPC6 channel activity suggesting that TRPC1/C5 inhibits TRPC6 channel activity. Inclusion of anti-TRPC1 and anti-TRPC5 antibodies, raised against intracellular epitopes, in the patch pipette solution blocked TRPC1/C5 channel currents but potentiated by about six-fold TRPC6 channel activity evoked by 1-100 nm Ang II in outside-out patches. Bath application of T1E3, an anti-TRPC1 antibody raised against an extracellular epitope, also increased Ang II-evoked TRPC6 channel activity. With high intracellular Ca(2+) buffering conditions (10 mm BAPTA), 10 nm Ang II-induced TRPC6 channel activity was increased by about five-fold compared to channel activity with low Ca(2+) buffering. In addition, increasing intracellular Ca(2+) levels ([Ca(2+)](i)) at the cytosolic surface inhibited 10 nm Ang II-evoked TRPC6 channel activity in inside-out patches. Moreover, in zero external Ca(2+) (0 [Ca(2+)](o)) 100 nm Ang II induced TRPC6 channel activity in outside-out patches. Pre-treatment with the PKC inhibitor, chelerythrine, markedly increased TRPC6 channel activity evoked by 1-100 nm Ang II and blocked the inhibitory action of [Ca(2+)](i) on TRPC6 channel activity. Co-immunoprecipitation studies shows that Ang II increased phosphorylation of TRPC6 proteins which was inhibited by chelerythrine, 0 [Ca(2+)](o) and the anti-TRPC1 antibody T1E3. These results show that TRPC6 channels evoked by Ang II are inhibited by TRPC1/C5-mediated Ca(2+) influx and stimulation of PKC, which phosphorylates TRPC6 subunits. These conclusions represent a novel interaction between two distinct vasoconstrictor-activated TRPC channels expressed in the same native VSMCs.
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Affiliation(s)
- J Shi
- Division of Basic Medical Sciences, St George's, University of London, London SW17 0RE, UK
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Chen K, Chang BZ, Ju M, Zhang XH, Gu H. Comparative study of photodynamic therapy vs. CO2laser vaporization in treatment of condylomata acuminata, a randomized clinical trial. Br J Dermatol 2007; 156:516-20. [PMID: 17300242 DOI: 10.1111/j.1365-2133.2006.07648.x] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Most conventional therapies for condylomata acuminata (CA) are traumatic and have high recurrence rates. OBJECTIVES To investigate the efficacy and safety of topical application of 5-aminolaevulinic acid (ALA) photodynamic therapy (PDT) for the treatment of CA. METHODS Sixty-five patients with CA were allocated into the treatment (ALA-PDT) group and treated with 20% ALA solution under occlusive dressing for 3 h followed by irradiation with the helium-neon laser at a dose of 100 J cm(-2) and a power of 100 mW. Another 21 CA patients were allocated into the control group and treated with the CO(2) laser. The treatment was to be repeated 1 week later if the lesion was not completely removed after the first treatment. RESULTS After one treatment, the complete removal rate was 95% in the ALA-PDT group and 100% in the control group. After two treatments with ALA-PDT, the complete removal rate in the treatment group was 100%. The recurrence rate for ALA-PDT group was 6.3% which was significantly lower than that in control group (19.1%, P < 0.05). Moreover, the proportion of patients with adverse effects in the ALA-PDT group (13.9%) was also significantly lower than that in control group (100%, P < 0.05). The side-effects in patients treated with ALA-PDT mainly included mild burning and/or stinging restricted to the illuminated area. CONCLUSIONS The present study shows that topical application of ALA-PDT is a simpler, more effective and safer therapy with a lower recurrence for treatment of CA compared with conventional CO(2) laser therapy.
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Affiliation(s)
- K Chen
- Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, China
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40
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Abstract
We report the molecular cloning from foetal brain of the human potassium channel heag2. The cDNA encodes a protein of 988 amino acids, 73% identical to heag1. Heag2 is expressed in the brain, but is also found in a range of tissues including skeletal muscle. In oocytes, the channel is a non-inactivating outward rectifier, with dependence of activation rate on holding potential. Compared with heag1, the conductance-voltage curve for heag2 was shifted to the left, the voltage sensitivity was less, activation kinetics were different, and the sensitivity to terfenadine was lower. The heag2 channel may have important physiological roles.
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Affiliation(s)
- M Ju
- School of Biomedical Sciences, University of Leeds, UK
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Hellstrom A, Perruzzi C, Ju M, Engstrom E, Hard AL, Liu JL, Albertsson-Wikland K, Carlsson B, Niklasson A, Sjodell L, LeRoith D, Senger DR, Smith LE. Low IGF-I suppresses VEGF-survival signaling in retinal endothelial cells: direct correlation with clinical retinopathy of prematurity. Proc Natl Acad Sci U S A 2001; 98:5804-8. [PMID: 11331770 PMCID: PMC33294 DOI: 10.1073/pnas.101113998] [Citation(s) in RCA: 374] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Retinopathy of prematurity is a blinding disease, initiated by lack of retinal vascular growth after premature birth. We show that lack of insulin-like growth factor I (IGF-I) in knockout mice prevents normal retinal vascular growth, despite the presence of vascular endothelial growth factor, important to vessel development. In vitro, low levels of IGF-I prevent vascular endothelial growth factor-induced activation of protein kinase B (Akt), a kinase critical for endothelial cell survival. Our results from studies in premature infants suggest that if the IGF-I level is sufficient after birth, normal vessel development occurs and retinopathy of prematurity does not develop. When IGF-I is persistently low, vessels cease to grow, maturing avascular retina becomes hypoxic and vascular endothelial growth factor accumulates in the vitreous. As IGF-I increases to a critical level, retinal neovascularization is triggered. These data indicate that serum IGF-I levels in premature infants can predict which infants will develop retinopathy of prematurity and further suggests that early restoration of IGF-I in premature infants to normal levels could prevent this disease.
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Affiliation(s)
- A Hellstrom
- Department of Clinical Neuroscience, Section of Ophthalmology, and International Pediatric Growth Research Center, The Queen Silvia Children's Hospital, 41685 Göteborg, Sweden
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Robinson GS, Ju M, Shih SC, Xu X, McMahon G, Caldwell RB, Smith LE. Nonvascular role for VEGF: VEGFR-1, 2 activity is critical for neural retinal development. FASEB J 2001; 15:1215-7. [PMID: 11344092 DOI: 10.1096/fj.00-0598fje] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- G S Robinson
- Children's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA
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Wang Y, Ju M, Wang H, Feng Y. [Study on the technological process of including volatile oil of Baizhu with beta-cyclodextrin]. Zhong Yao Cai 2000; 23:767-8. [PMID: 12575272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
The volatile oil of Baizhu was included with beta-CD. The factors affecting the formation of the inclusion compounds were researched by L9(3(4)) orthogonal test. The ratio of the oil in inclusion compounds and recovery of inclusion compounds were used as criteria in the test. The best conditions for inclusion were A2B3C1, that is, the compounds should be formed in the aqueous solution containing beta-CD and oil with a raio of 8:1, aqua destillate and beta-CD with a ratio of 4:1 for two hours.
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Affiliation(s)
- Y Wang
- Jiangsu Provincial Academy of Traditional Chinese Medicine, Nanjing 210028
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Abstract
Chiral cyclohexyl-pentyl-beta-D-maltoside (CYMAL-5) surfactant was evaluated in the enantioseparation of charged racemic species by capillary electrophoresis. CYMAL-5 is a glycosidic surfactant (GS) with a chiral maltose polar head group and a cyclohexyl-pentyl hydrophobic tail. At concentrations above its critical micellar concentration (CMC), CYMAL-5 produces neutral micelles in aqueous media. The neutral micelles migrate at the velocity of the electroosmotic flow (EOF). As expected, the CYMAL-5 system was only useful for the enantioseparation of charged chiral solutes. The enantioresolution of the CYMAL-5 can be manipulated over a wide range of electrolyte composition, e.g., pH, ionic strength and surfactant concentration. In the presence of EOF, and in all cases, there is an optimum surfactant concentration for maximum enantioresolution, which is located at low surfactant concentration for strongly hydrophobic solutes and at high surfactant concentration for relatively hydrophilic solutes. The presence of an optimum surfactant concentration for maximum enantioresolution is attributed to the EOF. At low pH values where the EOF is negligible, enantioresolution increased with increasing surfactant concentration in the useful concentration range in a way similar to chromatography.
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Affiliation(s)
- M Ju
- Department of Chemistry, Oklahoma State University, Stillwater 74078-3071, USA
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Fan YX, Ju M, Zhou JM, Tsou CL. Activation of chicken liver dihydrofolate reductase by urea and guanidine hydrochloride is accompanied by conformational change at the active site. Biochem J 1996; 315 ( Pt 1):97-102. [PMID: 8670138 PMCID: PMC1217202 DOI: 10.1042/bj3150097] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
It has been reported that the activation of dihydrofolate reductase (DHFR) from L1210 mouse leukaemia cells by KCl or thiol modifiers is accompanied by increased digestibility by proteinases [Duffy, Beckman, Peterson, Vitols and Huennekens (1987) J. Biol. Chem. 262, 7028-7033], suggesting a loosening up of the general compact structure of the enzyme. In the present study, the peptide fragments liberated from the chicken liver enzyme by digestion with trypsin in dilute solutions of urea or guanidine hydrochloride (GuHCl) have been separated by FPLC and sequenced. The sequences obtained are unique when compared with the known sequence of DHFR and thus allow the points of proteolytic cleavage identified for the urea- and GuHCl-activated enzyme to be at or near the active site. It was also indicated by the enhanced fluorescence of 2-p-toluidinylnaphthalene 6-sulfonate that conformational changes at the active site in dilute GuHCl parallel GuHCl activation. The above results indicate that the activation of DHFR in dilute denaturants is accompanied by a loosening up of its compact structure especially at or near the active site, suggesting that the flexibility at its active site is essential for the full expression of its catalytic activity.
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Affiliation(s)
- Y X Fan
- National Laboratory of Biomacromolecules, Institute of Biophysics, Academia Sinica, Beijing, China
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Abstract
The activation and inactivation of dihydrofolate reductase from chicken liver during denaturation in a wide concentration range of urea are compared with changes in intrinsic fluorescence. At 2 M urea the enzyme is activated 3.6-fold and is stable up to 12 h in the activated form. At 4 M urea, the enzyme activity increases about 5-fold initially but the activated enzyme loses activity rapidly to a level well below that of the native enzyme. The activated enzyme is stabilized in presence of either DHF or NADPH. The Kd and Km of the enzyme for the substrates at various urea concentrations were determined and compared. In the presence of 3 M urea, the values of Kd for DHF and NADPH increase 4-fold and 10-fold, respectively, whereas the corresponding Km values increase 25-fold and 3-fold. A large increase in Vmax is mainly responsible for the activation. The inactivation and unfolding in urea are both biphasic processes. For the fast phase, the rate constant of inactivation is 10-fold greater than that of unfolding in 4 M urea. The effect of (NH4)2SO4 on the activation and unfolding of the enzyme was also studied. The results suggest that the active site of the enzyme is more easily perturbed by denaturants; and the activated enzyme appears to have a more open and flexible conformation at the active site, which is favorable for the full expression of the catalytic power of the enzyme. A scheme for the sequential activation and inactivation of DHFR accompanying its unfolding by increasing concentrations of urea is proposed.
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Affiliation(s)
- Y X Fan
- National Laboratory of Biomacromolecules, Institute of Biophysics, Academia Sinica, Beijing, China
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Chen LY, Tian M, Du JS, Ju M. The changes of circular dichroism and fluorescence spectra, and the comparison with inactivation rates of angiotensin converting enzyme in guanidine solutions. Biochim Biophys Acta 1990; 1039:61-6. [PMID: 2162212 DOI: 10.1016/0167-4838(90)90226-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The circular dichroism (CD) spectrum of angiotensin converting enzyme (peptidyl-dipeptide hydrolase, EC 3.4.15.1) in the ultraviolet region was shown to have down negative peaks at 208 and 222 nm, indicating its peptide chain has an alpha-helical structure. The conformational changes of the enzyme during denaturation in guanidine solutions of increasing concentration, for 24 h at 4 degrees C, were associated with the disappearance of the two negative peaks of the CD spectra, less alpha-helical structure to various extents, a decrease in intensity of the intrinsic protein fluorescence, a red shift in the emission maximum at 340 nm and an increase in the band-width of the spectrum delta lambda. Together these findings demonstrate unfolding of the folded peptide chain of angiotensin converting enzyme and consequent exposure of its aromatic amino acid residues during denaturation. The rates of ellipticity (theta 220) changes of the enzyme during denaturation were less than those of the decrease in fluorescence intensity, demonstrating that the rate of degradation of its secondary structure was slower than that of its tertiary structure. Both the rates of inactivation and conformational change of the enzyme increased with increasing guanidine concentrations, within the range of 1.0-3.0 M. The enzyme inactivation had separate fast and slow processes. Both the rates and the extents of inactivation were much faster and larger than those of conformational changes. Compared with other enzymes, therefore, the angiotensin converting enzyme molecule appears to have a stable spatial structure, but its active site conformation is relatively unstable during denaturation.
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Affiliation(s)
- L Y Chen
- Cardiovascular Institute, Chinese Academy of Medical Sciences, Beijing
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Abstract
The expression for the total number of isomeric structures formed upon oxidation of SH groups has previously been correctly obtained for single chain proteins only. Expressions have now been obtained for molecules consisting of 2 and 4 peptide chains of the types A2 and A2B2. The latter type is particularly important as exemplified by the immunoglobulins and the insulin receptor. For the oxidation of insulin A chain with 4 SH groups, the total number of isomeric A2 structures is 59--this is different to all the values previously reported. Lack of consideration of symmetry problems probably accounts for the erroneous results obtained by earlier workers for the number of ways of randomly joining two identical chains. The total number of isomeric structures formed from the oxidation of two light and two heavy chains with 5 and 11 SH groups respectively of the human immunoglobulin GI has been found to be 4.8 X 10(16).
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Affiliation(s)
- Z X Wang
- Institute of Biophysics, Academia Sinica, Beijing, China
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