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Generalized Rashba Coupling Approximation to a Resonant Spin Hall Effect of the Spin–Orbit Coupling System in a Magnetic Field

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Chinese Physics Letters 2021年第7期38卷 122-129页

作者： Rui Zhang Yuan-Chuan biao Wen-Long You Xiao-guang Wang Yu-Yu Zhang Zi-Xiang Hu Department of Physics Chongqing UniversityChongqing 400044China College of Science Nanjing University of Aeronautics and AstronauticsNanjing 211106China Department of Physics Zhejiang UniversityHangzhou 310027China

We introduce a generalized Rashba coupling approximation to analytically solve confined two-dimensional electron systems with both the Rashba and Dresselhaus spin–orbit couplings in an external magnetic field.A solvable Hamiltonian is obtained by performing a simple change of basis,which has the same form as that with only Rashba *** Landau state becomes a new displaced-Fock state instead of the original Harmonic oscillator Fock *** energies are consistent with the numerical ones in a wide range of coupling strength even for a strong Zeeman splitting,exhibiting the validity of the analytical *** using the eigenstates,spin polarization correctly displays a jump at the energy-level crossing point,where the corresponding spin conductance exhibits a pronounced resonant *** the component of the Dresselhaus coupling increases,the resonant point shifts to a smaller value of the magnetic *** contrast to pure Rashba couplings,we find that the Dresselhaus coupling and Zeeman splittings tend to suppress the resonant spin Hall *** method provides an easy-to-implement analytical treatment to two-dimensional electron gas systems with both types of spin–orbit couplings by applying a magnetic field.

关键词： field coupling resonant

Reduction of OsFLW7 expression enhanced leaf area and grain production in rice

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Science Bulletin 2017年第24期62卷 1631-1633页

作者： Jing Xu Li Wang Yue-xing Wang Da-li Zeng Meng-yu zhou Xue Fu Wei-jun Ye Jiang Hu Li Zhu De-yong Ren Zhen-yu Gao Guo-jun Dong Long-biao Guo guang-heng Zhang Qian Qian State Key Laboratory of Rice Biology China National Rice Research Institute Hangzhou 310006 Zhejiang China

Increasing rice production is important to ensure food security in China. Exploring yield potential and identifying genes beneficial to yield are important goals in the modern rice breeding. Generally, controlling leaf morphology, increasing photosynthesis efficiency and modulating the ＂sink-source＂ relationship can pro- mote the breeding of high-yield rice as well as other cereal crops . The morphology of the leaf includes length, width and degree of curl after its emergence from the meristem and is determined by the establishment of polariW along the adaxial-abaxial, ventral-dorsal and medial-lateral axes and regulated at genetic, hormonal and environmental levels . Rice leaf morphology varies widely among rice subspecies and cultivars. Quantitative trait loci （QTLs） affecting leaf shape commonly have pleiotropic effects on rice yield , which are more useful than mutant genes for studying the molecular mechanism of leaf shape regulation and their application to rice breeding.

关键词： Reduction OsFLW7 expression enhanced leaf area grain production in rice

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安顺地区结核分枝杆菌基因分型及耐药性分析

贵州医科大学学报 2024年第6期49卷 852-858,872页

作者：刘洪飞徐彬佟玉峰孙广李小多张彪蒋红梅贵州医科大学医学检验学院贵州贵阳550000 安顺市人民医院医学检验科贵州安顺561000 安顺市人民医院呼吸内科贵州安顺561000

目的研究贵州省安顺地区结核分枝杆菌(MTB)主要基因分型及耐药性。方法采用RD105基因缺失法和双重PCR法对安顺地区152株MTB临床分离株进行基因分型、药物敏感试验分析耐药性,采用基因测序技术对北京型MTB利福平耐药基因RNA聚合酶β亚基(... 详细信息

目的研究贵州省安顺地区结核分枝杆菌(MTB)主要基因分型及耐药性。方法采用RD105基因缺失法和双重PCR法对安顺地区152株MTB临床分离株进行基因分型、药物敏感试验分析耐药性,采用基因测序技术对北京型MTB利福平耐药基因RNA聚合酶β亚基(rpoB)进行测序。结果152株MTB中,122株(80.26%)为北京型、30株(19.74%)为非北京型;108株MTB对抗结核药物敏感,44株对16种抗结核药物耐药,总耐药率为28.95%;44株MTB耐药菌株中31例对利福平耐药,占70.45%,北京型MTB对利福平耐药率显著高于非北京型(χ^(2)=6.896,P=0.009),非利福平耐药结核菌株共13株、占耐药结核菌株的29.55%;北京型MTB利福平耐药rpoB基因测序结果表明,相关位点突变共15株,其中最显著的突变位点是rpoB450、为Ser450Leu,共7株(7/15,46.67%)。结论贵州省安顺地区MTB主要为北京型,主要对利福平耐药,耐药基因rpoB的突变位点为Ser450Leu。

关键词：结核分枝杆菌基因分型耐药性基因测序 RD105 双重PCR

Theoretical investigation into the effect of rail vibration dampers on the dynamical behaviour of a high-speed railway track

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2017年第8期18卷 631-647页

作者： Xin-biao XIAO Ya-guang LI Ting-sheng ZHONG Xiao-zhen SHENG State Key Laboratory of Traction Power Southwest Jiaotong University Chengdu 610031 China

Installation of rail vibration dampers （rail dampers for short） onto rails between sleepers is one of the measures to control rail noise generation and roughness growth. Amid the rapid expansion of high-speed and underground railway networks in China, many suppliers are actively marketing and promoting their products, often giving confusing information. In this paper, a parametric study is used to investigate the effect of rail dampers on the dynamical behavior of a Chinese high-speed railway track. The Fourier transform-based method developed for analyzing dynamics of a railway track as an infinitely long periodic structure, with or without rail dampers, is applied in the investigation. It is hoped that results in this paper can help develop the understanding of the working mechanism of rail dampers, and provide useful information for product design and application.

关键词： Rail damper Track dynamics Dispersion curves Vibration decay rate

Ursolic acid induces neural regeneration after sciatic nerve injury

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Neural Regeneration Research 2013年第27期8卷 2510-2519页

作者： biao Liu Yan Liu guang Yang Zemin Xu Jiajun Chen Department of Hand Surgery China-Japan Union Hospital of Jilin University Department of Neurology China-Japan Union Hospital of Jilin University

In this study, we aimed to explore the role of ursolic acid in the neural regeneration of the injured sciatic nerve. BALB/c mice were used to establish models of sciatic nerve injury through unilateral sciatic nerve complete transection and microscopic anastomosis at 0.5 cm below the ischial tuber-osity. The successful y generated model mice were treated with 10, 5, or 2.5 mg/kg ursolic acid via intraperitoneal injection. Enzyme-linked immunosorbent assay results showed that serum S100 protein expression level gradual y increased at 1-4 weeks after sciatic nerve injury, and significantly decreased at 8 weeks. As such, ursolic acid has the capacity to significantly increase S100 protein expression levels. Real-time quantitative PCR showed that S100 mRNA expression in the L 4-6 segments on the injury side was increased after ursolic acid treatment. In addition, the muscular mass index in the soleus muscle was also increased in mice treated with ursolic acid. Toluidine blue staining revealed that the quantity and average diameter of myelinated nerve fibers in the injured sciatic nerve were significantly increased after treatment with ursolic acid. 10 and 5 mg/kg of ursolic acid produced stronger effects than 2.5 mg/kg of ursolic acid. Our findings indicate that ursolic acid can dose-dependently increase S100 expression and promote neural regeneration in BALB/c mice fol owing sciatic nerve injury.

关键词： neural regeneration traditional Chinese medicine ursolic acid triterpenoid sciatic nerve peripheralnerve injury S100 muscular atrophy nerve myelin sheath grants-supported paper neuroregeneration

Aligned fibers enhance nerve guide conduits when bridging peripheral nerve defects focused on early repair stage

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Neural Regeneration Research 2019年第5期14卷 903-912页

作者： Qi Quan Hao-Ye Meng biao Chang guang-Bo Liu Xiao-Qing Cheng He Tang Yu Wang Jiang Peng Qing Zhao Shi-Bi Lu Department of Orthopedic Surgery Key Laboratory of Musculoskeletal Trauma & War Injuries PLA Beijing Key Lab of Regenerative Medicine in Orthopedics Chinese PLA General Hospital School of Materials Science and Engineering University of Science & Technology Beijing Department of Laser Medicine Chinese PLA General Hospital Neural Regeneration Co-innovation Center of Jiangsu Province Department of Orthopedic Surgery First Affiliated Hospital of PLA General Hospital

Nerve conduits enhance nerve regeneration in the repair of long-distance peripheral nerve defects. To help optimize the effectiveness of nerve conduits for nerve repair, we developed a multi-step electrospinning process for constructing nerve guide conduits with aligned nanofibers. The alignment of the nerve guide conduits was characterized by scanning electron microscopy and fast Fourier transform. The mechanical performance of the nerve guide conduits was assessed by testing for tensile strength and compression resistance. The biological performance of the aligned fibers was examined using Schwann cells, PC12 cells and dorsal root ganglia in vitro. Immunohistochemistry was performed for the Schwann cell marker S100 and for the neurofilament protein NF200 in PC12 cells and dorsal root ganglia. In the in vivo experiment, a 1.5-cm defect model of the right sciatic nerve in adult female Sprague-Dawley rats was produced and bridged with an aligned nerve guide conduit. Hematoxylin-eosin staining and immunohistochemistry were used to observe the expression of ATF3 and cleaved caspase-3 in the regenerating matrix. The recovery of motor function was evaluated using the static sciatic nerve index. The number of myelinated fibers, axon diameter, fiber diameter, and myelin thickness in the distal nerve were observed by electron microscopy. Gastrocnemius muscle mass ratio was also determined. The analyses revealed that aligned nanofiber nerve guide conduits have good mechanical properties and can induce Schwann cells, PC12 cells and dorsal root ganglia to aggregate along the length of the nanofibers, and promote the growth of longer axons in the latter two(neuronal) cell types. The aligned fiber nerve conduits increased the expression of ATF3 and cleaved caspase-3 at the middle of the regenerative matrix and at the distal nerve segment, improved sciatic nerve function, increased muscle mass of the gastrocnemius muscle, and enhanced recovery of distal nerve ultrastructure. Coll

关键词： nerve regeneration nerve guide conduit electrospinning peripheral nerve injury aligned fiber sciatic nerve structure mechanical function nerve scaffold nanofiber neural regeneration

Effects of the potassium application rate on lipid synthesis and eating quality of two rice cultivars

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Journal of Integrative Agriculture 2023年第7期22卷 2025-2040页

作者： CHEN guang-yi PENG Li-gong LI Cong-mei TU Yun-biao LAN Yan WU Chao-yue DUAN Qiang ZHANG Qiu-qiu YANG Hong LI Tian Crop Ecophysiology and Cultivation Key Laboratory of Sichuan Province College of AgronomySichuan Agricultural UniversityChengdu 611130P.R.China

Lipid content has an important effect on rice eating quality,but the effects of fertilizer application rate on the lipid synthesis and eating quality of rice are not well ***(K)has a strong influence on rice quality and the requirement for K fertilizer in rice is greater than for nitrogen(N)and phosphorus(P)*** investigate the effects of K fertilizer on the lipid synthesis and eating quality of rice,we used Nanjing 9108(NJ9108,japonica)and IR72(indica)rice as experimental materials and four K levels:K0(0 kg ha^(-1)),K1(90 kg ha^(-1)),K2(135 kg ha^(-1))and K3(180 kg ha^(-1)).The results showed that the lipid content,free fatty acid(FFA)content,unsaturated fatty acid(UFA)content,malonyl-CoA(MCA)content,phosphatidic acid(PA)content,lipid synthesis-related enzyme activities and eating quality first increased and then decreased with increasing K in both *** maximum values were obtained under ***,the saturated fatty acid(SFA)content showed the opposite *** significant differences were found in pyruvate(PYR)content among the K *** protein and oxaloacetic acid(OAA)contents and phosphoenolpyruvate carboxylase(PEPCase)activity of NJ9108 first decreased and then increased with increasing K,and the minimum values were obtained under K2;while IR72 showed the opposite trend and the maximum values were obtained under ***,increasing K optimized the fatty acid components and increased the lipid content and eating quality of rice by enhancing lipid synthesis-related enzyme activities and regulating substrate competition for lipid and protein *** optimal K application rate for lipid synthesis,eating quality and grain yield was 135 kg ha^(-1)for both cultivars.

关键词： rice potassium application rate lipid content lipid synthesis-related enzyme fatty acid components eating quality

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红霉素肟硅醚化绿色工艺研究

精细化工中间体 2024年第4期54卷 39-41页

作者：单继雷汤旗曹塞北金勇卢标华李广青浙江国邦药业有限公司浙江上虞312369

研究了红霉素肟硅醚化绿色合成工艺。以红霉素A肟为原料,盐酸甲醇为催化剂,进行硅醚化反应,并优化了反应条件。优化条件下,硅醚化反应收率96.4%,产品纯度94.4%。该工艺可以替代现有盐酸吡啶为催化剂的硅烷化反应,达到绿色合成、降低原... 详细信息

研究了红霉素肟硅醚化绿色合成工艺。以红霉素A肟为原料,盐酸甲醇为催化剂,进行硅醚化反应,并优化了反应条件。优化条件下,硅醚化反应收率96.4%,产品纯度94.4%。该工艺可以替代现有盐酸吡啶为催化剂的硅烷化反应,达到绿色合成、降低原辅料成本、并减少三废的目的,适合工业化生产。

关键词：红霉素A肟硅醚化反应盐酸甲醇绿色合成

Lattice Boltzmann modeling and simulation of compressible flows

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Frontiers in Biology 2012年第5期7卷 582-600页

作者： Ai-Guo Xu guang-Cai Zhang Yan-biao Gan Feng Chen Xi-Jun Yu National Key Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsP.O.Box 8009-26Beijing 100088China North China Institute of Aerospace Engineering Langfang 065000China School of Science Linyi UniversityLinyi 276005China

In this mini-review we summarize the progress of Lattice Boltzmann （LB） modeling and simulating compressible flows in our group in recent years. Main contents include （i） Single-Relaxation-Time （SRT） LB model supplemented by additional viscosity, （ii） Multiple-Relaxation-Time （MRT） LB model, and （iii） LB study on hydrodynamic instabilities. The former two belong to improvements of physical modeling and the third belongs to simulation or application. The SRT-LB model sup- plemented by additional viscosity keeps the original framework of Lattice Bhatnagar-Gross Krook （LBGK）. So, it is easier and more convenient for previous SRT-LB users. The MRT-LB is a com- pletely new framework for physical modeling. It significantly extends the range of LB applications. The cost is longer computational time. The developed SRT-LB and MRT-LB are complementary from the sides of convenience and applicability.

关键词： lattice Boltzmann modeling compressible flows shock waves hydrodynamic instability