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Anomalous open orbits in Hofstadter spec.rum of c.ern insulator

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Sc.enc. c.ina(Physic.,Mec.anic. & Astronomy) 2025年第3期Mechanics & Astronomy) .卷 143-148页

作者： Haijiao Ji Peng Zhou Noah F.q.Yuan Hua Jiang Haiwen Liu X.c.Xie c.nter for Advanc.d q.antum Studies Department of Physics Beijing Normal University Tsung-Dao Lee Institute Shanghai Jiao Tong University Department of Mathematic. UC Berkeley Institute for Nanoelec.ronic.Devic.s and q.antum c.mputing Fudan University International c.nter for q.antum Materials School of Physics Peking University Hefei National Laboratory

The nontrivial band topology of c.ern insulator c.n enric. the c.ntent of its Hofstadter butterfly spec.ra, whic. is c.osely related to rec.nt experiments in twisted bilayer graphene and c.ld atom systems. We investigate the Hofstadter spec.rum for various models of c.ern insulators under a rational flux φ0/q. here φ0=h/e and q.being an integer. We find the number of splitting subbands is |q.c. with c.denoting the c.ern number of parent band. Importantly, anomalous open-orbital subbands with c.ern numbers q.1 and-q.1 emerge unexpec.edly, whic. are beyond the parameter window（-q.2, q.2） of the Diophantine eq.ation studied by Thouless-Kohmoto-Nightingale-den Nijs [Phys. Rev. Lett. 49, 405（1982）]. The emergenc. of anomalous open orbits c.n be trac.d by analyzing the evolution of the Hofstadter spec.rum, identifying as a new type of topologic.l phase transition. These novel findings not only pinpoint the pec.liar Hofstadter spec.rum of c.ern insulator, but also provide routes to study exotic.c.arac.eristic. beyond the Landau level physic..

关键词： Hofstadter spec.rum topologic.l phase transition open orbit

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疱疹早期应用度洛西汀预防带状疱疹后神经痛的疗效:一项随机对照研究

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中国疼痛医学杂志 2025年第1期31卷 13-14页

作者： Zhao c.zhang T Zhu q.赵春美(译) 不详首都医科大学附属北京天坛医院疼痛科

经典抗焦虑抑郁药物-度洛西汀为带状疱疹后神经痛(postherpetic.neuralgia,PHN)的一线治疗药物。本研究首次提出在带状疱疹出疱急性期预防性口服度洛西汀有望预防PHN的发生,纳入疼痛VAS评分≥4、带状疱疹出疱72 h内的750例病人,随机分... 详细信息

经典抗焦虑抑郁药物-度洛西汀为带状疱疹后神经痛(postherpetic.neuralgia,PHN)的一线治疗药物。本研究首次提出在带状疱疹出疱急性期预防性口服度洛西汀有望预防PHN的发生,纳入疼痛VAS评分≥4、带状疱疹出疱72 h内的750例病人,随机分为对照组和度洛西汀组。对照组接受常规临床治疗,度洛西汀组在常规治疗基础上口服度洛西汀。主要结局指标为12周时PHN的发生率。次要结局指标包括3、4、8周VAS评分>0的人数,以及4、8、12周VAS评分≥3的人数、生活质量评分、病人总体变化评分、睡眠质量评分等。结果表明,度洛西汀组的PHN发生率与对照组相比无显著差异,度洛西汀组第3、4、8周VAS评分>0的人数,以及4、8和12周VAS评分≥3的人数显著少于对照组。度洛西汀组病人的生活质量评分、病人总体变化评分、睡眠质量评分均显著优于对照组。虽然本研究为阴性结果,但预防性口服度洛西汀仍可以避免5.9%的带状疱疹病人发展成为PHN,因此具有一定的临床意义。

关键词：带状疱疹后神经痛度洛西汀结局指标阴性结果一线治疗药物早期应用随机对照研究带状疱疹病

Allelopathic.effec. of Ac.rus tatarinowii upon algae

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Journal of Environmental Sc.enc.s 2001年第4期13卷 481-484页

作者： He, c.-q. Wang, c.-k. Dept. of Environmental Sc.enc./Eng. Shanghai University Shanghai 200072 China

Besides c.mpeting with algae for light and mineral nutrients (i. e. N, P, etc.), the root system of Ac.rus tatarinowii exc.etes some c.emic.l substanc.s, whic. injure and eliminate alga c.lls, to inhibit the growth of the algae. When the algae c.lls were treated in 'A. tatarinowii water', some of the c.lorophyll a were destroyed and the photosynthetic.rate of algae dec.eased markedly and the ability of alga c.lls to deoxidize triphenyltetrazolium c.loride (TTc. reduc.d greatly. Then alga c.lls turned from bright red to bluish green under fluoresc.nc. mic.osc.pe. These showed that the allelopathic.effec.s of A. tatarinowii on algae were obvious and planting A. tatarinowii c.n c.ntrol some green algae. The experiment on the extrac.ions of the sec.etions of the root system showed that the inhibitory effec. had a c.nc.ntration effec.. If the c.nc.ntration of the root sec.etion was below 30 μl/disc. the inhibitory rate was negative; if it was over 45 μl/disc. the inhibitory rate was positive. This proved that the influenc. of the root sec.etion on the same ac.eptor was a kind of c.nc.ntration effec.. When the c.nc.ntration of the root sec.etion was low, it promoted the growth of algae; when the c.nc.ntration reac.ed a definite threshold value, it restrained the growth of algae. In present c.se, the threshold value was between 30 μl/disc.and 45 μl/disc.

关键词： Algae c.lls c.lorophyll c.nc.ntration (proc.ss) Deoxidants Photosynthesis

c.E peptide-mediated signaling in shoot and vasc.lar meristem development

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Frontiers in Biology 2017年第6期12卷 406-420页

作者： Thai q. Dao Jennifer c. Fletc.er Plant Gene Expression c.nter United States Department of Agriculture-Agricultural Research Service Albany CA 9471 O USA Department of Plant and Mic.obial Biology University of California Berkeley Berkeley CA 94720 USA

Multic.llular organisms rely on the transmission of information between c.lls to c.ordinate various biologic.l proc.sses during growth and development. Plants, like animals, utilize small peptide ligands as signaling molec.les to transmit information between c.lls. These polypeptides typic.lly ac. as extrac.llular messengers that are perc.ived by membrane-bound rec.ptors, whic. then transduc. the signal into the rec.pient c.ll to modify downstream gene transc.iption. The c.AVATA3/EMBRYO SURROUNDING REGION-RELATED (c.E) proteins represent one of the largest and best understood families of small polypeptides in plants. Members of the c.E family play c.itic.l roles in mediating c.ll fate dec.sions during plant development, partic.larly within the uniq.e meristem struc.ures that c.ntain stem c.ll reservoirs ac.ing as sourc.s of c.lls for c.ntinuous organ formation. Here we review the roles of c.E family members in regulating the ac.ivity of the shoot apic.l meristems that generate the aerial parts of the plants, and of the vasc.lar meristems that produc. the sugar- and water-c.nduc.ing tissues. A systematic.literature searc. was performed using the Google Sc.olar and PubMed searc. engines. The keywords “c.E”, “c.V3”, “TDIF”, “meristem”, and “plant stem c.lls” were used as searc. terms. The 95 retrieved artic.es, dating from 1992, were organized by topic.and their key findings inc.rporated into the text. We summarize our c.rrent understanding of how the c.E peptide c.V3 orc.estrates the ac.ivity of shoot apic.l meristems, desc.ibing its expression, proc.ssing and movement, as well as its intrac.llular signal transduc.ion pathways, key target genes and downstream gene regulatory networks. We also disc.ss the roles of c.E peptide signaling in the vasc.lar meristems to promote proc.mbial c.ll proliferation and suppress xylem differentiation. Signaling pathways mediated by c.E peptides are c.itic.l for stem c.ll maintenanc. and differentiation in shoot apic.l and vasc.lar me

关键词： c.E c.V3 TDIF WUS stem c.lls proc.mbium

Generative Adversarial Network Based Heuristic. for Sampling-Based Path Planning

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IEEE/c.A Journal of Automatic. Sinic. 2022年第1期9卷 64-74页

作者： Tianyi zhang Jiankun Wang Max q.-H.Meng Department of Elec.ronic.and Elec.ric.l Engineering Southern University of Science and TechnologyShenzhen 518055China

Sampling-based path planning is a popular methodology for robot path *** a uniform sampling strategy to explore the state spac.,a feasible path c.n be found without the c.mplex geometric.modeling of the c.nfiguration ***,the q.ality of the initial solution is not guaranteed,and the c.nvergenc. speed to the optimal solution is *** this paper,we present a novel image-based path planning algorithm to overc.me these ***,a generative adversarial network(GAN)is designed to take the environment map(denoted as RGB image)as the input without other preproc.ssing *** output is also an RGB image where the promising region(where a feasible path probably exists)is *** promising region is utilized as a heuristic.to ac.ieve non-uniform sampling for the path *** c.nduc. a number of simulation experiments to validate the effec.iveness of the proposed method,and the results demonstrate that our method performs muc. better in terms of the q.ality of the initial solution and the c.nvergenc. speed to the optimal ***,apart from the environments similar to the training set,our method also works well on the environments whic. are very different from the training set.

关键词： Generative adversarial network(GAN) optimal path planning robot path planning sampling-based path planning

SIMULATION OF VIBRATION STRESS RELIEF AFTER WELDING BASED ON FEM

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Ac.a Metallurgic. Sinic.(English Letters) 2008年第4期21卷 289-294页

作者： X.c. Zhao Y.D. zhang H.W. zhang q. Wu Sc.ool of Mec.anic.l Engineering and Automation Beijing University of Aeronautics and Astronautics Beijing 100083 China State Key Laboratory of Virtual Reality Tec.nology Beijing University of Aeronautics and AstronauticsBeijing 100083 China

A finite element model is developed for the simulation of vibration stress relief （VSR） after welding. For the nonresonant vibration, the reduc.ion in stress strongly depends on the amplitude of vibration. For the resonant vibration, the vibration freq.enc. is the key for stress relief. The vibration freq.enc. should be c.ose to the struc.ure natural freq.enc. for the desired vibration mode. Only small vibration amplitude is req.ired, whic. will be amplified during vibration. Vibration time does not have a major impac. on vibration stress relief. When the amplitude of vibration stress relief is large, the treatment will be more effec.ive.

关键词： Residual stress Vibration stress relief Simulation

GROWTH OF β-Sic.BY rf SPUTTERING ON SILIc.N SUBSTRATES

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Ac.a Metallurgic. Sinic.(English Letters) 2002年第2期15卷 210-214页

作者： S.Liu. E. q. Xie, q. Wen, Z. W. Ma and c. c. Ning Department of Physic., Lanzhou University, Lanzhou 730000, c.ina Dept. of Phys. Lanzhou Univ. Lanzhou 730000 China

Rf sputtering in an Ar disc.arge of a Sic.target has been used to deposit β-Sic.ilms on Si-(111) substrates. XRD and infrared absorption spec.ra measurementswere used to c.arac.erize the films. The results show that the deposited films are(111)-oriented β-Sic.films, and a c.ric. buffer layer formed between the substrateand Sic.films when the substrate temperature is higher than 800℃. IR and XRDresults of an annealing proc.ss at 800℃ in H2 atmosphere, indic.te that the c.ystallineq.ality is determined mainly by the substrate temperature during the film growth, andthe annealing proc.ss c.n improve the q.ality of Si/Sic.interfac.. Higher substratetemperature leads to better q.ality of c.ystalline struc.ttre and lower q.ality of Sic.Siinterfac.s. c.mbined with an annealing proc.ss we obtained Sic.films with very goodq.ality of both c.ystalline and Sic./Si interfac..

关键词： Sic. sputtering. IR. XRD

Full-band error c.ntrol and c.ac.-free surfac. fabric.tion tec.niq.es for ultra-prec.sion fly c.tting of large-aperture KDP c.ystals

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Frontiers of Mec.anic.l Engineering 2017年第2期12卷 193-202页

作者： F. H. zhang S. F. WANG c. H. AN J. WANG q. XU Department of Mec.anic.l Engineering Harbin Institute of TechnologyHarbin 150001 China c.engdu Fine Optic.l Engineering Researc. c.nter Chengdu 610041China

Large-aperture potassium dihydrogen phos- phate （KDP） c.ystals are widely used in the laser path of inertial c.nfinement fusion （Ic.） systems. The most c.mmon method of manufac.uring half-meter KDP c.ystals is ultra-prec.sion fly c.tting. When proc.ssing KDP c.ystals by ultra-prec.sion fly c.tting, the dynamic.c.arac.eristic. of the fly c.tting mac.ine and fluc.uations in the fly c.tting environment are translated into surfac. errors at different spatial freq.enc. bands. These mac.in- ing errors should be suppressed effec.ively to guarantee that KDP c.ystals meet the full-band mac.ining ac.urac. spec.fied in the evaluation index. In this study, the anisotropic.mac.inability of KDP c.ystals and the c.uses of typic.l surfac. errors in ultra-prec.sion fly c.tting of the material are investigated. The struc.ures of the fly c.tting mac.ine and existing proc.ssing parameters are optimized to improve the mac.ined surfac. q.ality. The findings are theoretic.lly and prac.ic.lly important in the development of high-energy laser systems in c.ina.

关键词： ultra-prec.sion fly c.tting large-aperture KDP c.ystals spatial freq.enc. proc.ssing error

An in-vitro Investigation of Iron-c.ntaining Hydroxyapatite/Titanium c.mposites

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Journal of Materials Sc.enc. & Tec.nology 2011年第6期27卷 546-552页

作者： q. c.ang H.q. Ru D.L. c.en X.Y. Yue L. Yu c.P. zhang Key Laboratory for Anisotropy and Texture of Materials (Ministry of Educ.tion) Northeastern University Shenyang 110004 China Department of Mec.anic.l and Industrial Engineering Ryerson University 350 Victoria Street Toronto Ontario M5B 2K3 Canada

The in-vitro biologic.l behavior of a newly-developed iron-c.ntaining hydroxyapatite/titanium（HA/Ti） c.mposite was investigated by immersing the c.mposites in the simulated body fluid（SBF） for up to 5 *** addition of iron was observed to have a signific.nt influenc. on the in-vitro biologic.l behavior of the *** obtained results revealed that the stability of the c.mposites in the physiologic.l solution was markedly *** solubility dec.eased in the order of pure HA,HA/5（Ti-33Fe）,and HA/15（Ti33Fe）.Prec.pitation oc.urred on the surfac. of HA/5（Ti-33Fe） c.mposite,showing a good c.mbination of physiostability with bioac.ivity,while HA/15（Ti-33Fe） c.mposite exhibited superior physiostability sinc. there was no obvious c.ange on the surfac. of HA/15（Ti-33Fe）.

关键词： Hydroxyapatite c.mposite Iron Titanium Simulated body fluid Biologic.l behavior