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Chitin scaffold combined with autologous small nerve repairs sciatic nerve defects

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Neural Regeneration Research 2022年第5期17卷 1106-1114页

作者： Bo Wang Chang-Feng Lu Zhong-Yang Liu Shuai Han Pi Wei Dian-Ying Zhang Yu-Hui Kou Bao-Guo Jiang department of Orthopedics and Trauma Key Laboratory of Trauma and Neural Regeneration(Ministry of Education/Peking University)Peking University People’s HospitalBeijingChina department of Orthopedics Chinese PLA General HospitalBeijingChina National Clinical Research Center for Orthopedics Sports Medicine&RehabilitationBeijingChina

Although autologous nerve transplantation is the gold standard for treating peripheral nerve defects,it has many clinical *** an alternative,various tissue-engineered nerve grafts have been developed to substitute for autologous *** this study,a novel nerve graft composed of chitin scaffolds and a small autologous nerve was used to repair sciatic nerve defects in *** novel nerve graft greatly facilitated regeneration of the sciatic nerve and myelin sheath,reduced atrophy of the target muscle,and effectively restored neurological *** the epineurium of the small autogenous nerve was removed,the degree of nerve regeneration was similar to that which occurs after autogenous nerve *** findings suggest that our novel nerve graft might eventually be a new option for the construction of tissue-engineered nerve *** study was approved by the Research Ethics Committee of Peking University People's Hospital(approval No.2019 PHE27)on October 18,2019.

关键词： autologous small nerve chitin scaffold nerve defect nervous system peripheral nerve injury peripheral nerve regeneration sciatic nerve trauma

Associations between thyroid function and autoimmunity indicators and in vitro fertilization/intracytoplasmic sperm injection outcomes in euthyroid PCOS women

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中华医学杂志(英文版) 2024年第16期137卷 2024 Apr 17页

作者： Jiang Huahua Chen Lixue Huang Ning Shi Huifeng Chi Hongbin Yang Rui Long Xiaoyu Qiao Jie department of Obstetrics and Gynecology Center for Reproductive Medicine Peking University Third Hospital Beijing China National Clinical Research Center for Obstetrics and Gynecology Peking University Third Hospital Beijing China Key Laboratory of Assisted Reproduction Peking University Ministry of Education Beijing China Beijing Key Laboratory of Reproductive Endocrinology and Assisted Reproductive Technology Beijing China department of Obstetrics and Gynecology Peking University Third Hospital Beijing China National Centre for Healthcare Quality Management in Obstetrics Beijing China Beijing Advanced Innovation Center for Genomics Peking University Beijing China Peking-Tsinghua Center for Life Sciences Peking University Beijing China

The characters of dense dispersion managed soliton in optical fiber transmission systems

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Chinese Optics Letters 2003年第3期1卷 136-138页

作者：郭淑琴周国生黄肇明 department of Physics Shanxi University Taiyuan 030006 School of Communication and Information Engineering Shanghai University Shanhai 200072 department of Physics Shanxi UniversityTaiyuan 030006 School of communication and Information Engineering Shanghai UniversityShanhai 200072

The properties of ultra-short dense dispersion-managed soliton (DBMS) in optical fiber links are investigated. They show some excellent characters, such as, reducing pulse's breathing extent greatly, facing fewer mutual interactions and tolerating larger local dispersion. In general, DBMS is more stable than a conventional dispersion-managed soliton in high-capacity systems. Excessively dense dispersion compensation is more suitable for systems with weak nonlinear effect.

关键词： of on be it in The characters of dense dispersion managed soliton in optical fiber transmission systems

Manipulation of polarization conversion and multiplexing via all-silicon phase-modulated metasurfaces

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Chinese Optics Letters 2022年第4期20卷 82-86页

作者：岳震李继涛郑程龙李杰陈明阳郝璇若徐航汪奇张雅婷姚建铨 Key Laboratory of Opto-Electronics Information Technology(Tianjin University) Ministry of EducationSchool of Precision Instruments and Opto-Electronics EngineeringTianjin UniversityTianjin 300072China department of Optoelectronic Information Science and Engineering Jiangsu UniversityZhenjiang 212013China

Phase-modulated metasurfaces that can implement the independent manipulation of co-and cross-polarized output waves under circularly polarized[CP]incidence have been *** this,we introduce one particular metasurface composed of meta-atoms with a phase difference of 2π/3 to generate specific elliptically polarized waves under various polarized ***,a metasurface composed of these above meta-atoms and the meta-atoms with a phase difference of π/3 arranged in a certain rule can realize polarization conversion function between linearly polarized and CP *** designs shed new light on multifarious optical devices and may further promote the development of metasurface polarization optics.

关键词： phase-modulated metasurfaces polarization conversion multiplexing

PREPARATION OF SULPHONATE-CONTAINING POLYMER PARTICLES VIA SEMI-CONTINUOUS EMULSION COPOLYMERIZAION OF STYRENE AND SODIUM STYRENE SULPHONATE

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Chinese Journal of Polymer Science 2011年第1期29卷 111-116页

作者：阚成友 department of Chemical Engineering and Key Laboratory of Advanced Materials of Ministry of education Tsinghua University

Submicron-sized P（St-NaSS） latexes were prepared via a semi-continuous emulsion copolymerization of styrene （St） and sodium styrene sulphonate （NaSS） in the presence of anionic surfactant, in which NaSS aqueous solution and St were separately dropwise charged into the polymerization system at the same time. The hydrodynamic diameter of the latex particles was measured by dynamic light scattering （DSL） method, and the NaSS unit content of the purified copolymer by water extraction was calculated based on the elementary analysis. Results showed that the copolymerization could be performed smoothly with the monomer conversion more than 96% in the absence of crosslinker, and PNaSS homopolymer could be removed from the latex product by water extraction for 28 h. The weight loss in the water extraction tended to decrease and the NaSS unit content of the purified copolymer tended to increase with the increase of monomer feeding time, and both of them increased with the increase of NaSS/St mole ratio in the charge. The introduction of divinyl benzene （DVB） could decrease the weight loss in the water extraction and increase the NaSS unit content of the purified copolymer. When 25/75 mole ratio of NaSS/St and 11 mol% DVB of total NaSS and St were used in the recipe, and the monomer feeding time was 3 h in copolymerization, the NaSS unit content of the purified copolymer reached 7.31 mol%.

关键词： Emulsion polymerization Sulphonate-containing polymer particles Crosslinking Poly(styrene-sodium styrene sulphonate).

Effect of ultrasonic irradiation and /or halogenation on the catalytic performance of γ-Al_2O_3 for methanol dehydration to dimethyl ether

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燃料化学学报 2013年第9期41卷 1077-1084页

作者： Sameh M.K.Aboul-Fotouh Ain Shams University Faculty of EducationChemistry DepartmentRoxyCairo 11566Egypt

Dimethyl ether(DME) is amongst one of the most promising alternative,renewable and clean fuels being considered as a future energy *** this study,the comparative catalytic performance of the halogenated γ-Al 2 O 3 prepared from two halogen precursors(ammonium chloride and ammonium fluoride) is *** impact of ultrasonic irradiation was evaluated in order to optimize both the halogen precursor for the production of DME from methanol in a fixed bed *** catalysts were characterized by SEM,XRD,BET and NH *** reaction conditions where the temperature ranged from 200 to 400 ℃ with a WHSV = 15.9 h-1was found that the halogenated catalysts showed higher activity at all reaction ***,the halogenated alumina catalysts prepared under the effect of ultrasonic irradiation showed higher performance of γ-Al 2 O 3 for DME *** chlorinated γ-Al 2 O 3 catalysts showed a higher activity and selectivity for DME production than fluorinated versions.

关键词：化学原理方法化学动力学

Explanation of Unusual Photoluminescence Behavior from InAs Quantum Dots with InAlAs Capping

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Journal of Materials Science & Technology 2005年第4期21卷 559-562页

作者： Zhongyuan YU Yongqiang WEI School of Science Beijing University of Posts and Telecommunications Beijing 100876 China Key Laboratory of Optical communication and Lightwave Technologies (BUPT) Ministry of Education Beijing 100876 China Photonics Laboratory Department of Microtechnology and Nanoscience Chalmers University of Technology SE-412 96 Gǒteborg Sweden

The effect of different kinds of cap layers on optical property of InAs quantum dots （QDs） on GaAs （100） substrate was studied. Temperature dependent photoluminescence （PL） indicates that the PL integrated intensity from the ground state of InAs QDs capped with an intermediate InAIAs layer drops very little as compared to QDs capped with a thin InGaAs or GaAs cap layer from 15 K up to room temperature. PL integrated intensity ratio of the first excited to ground states for InAs QDs capped with an intermediate InAIAs layer is unexpectedly decreased with increasing temperature, which are attributed to phonon bottleneck effect. A virtual barrier is proposed to describe this physics process and shows good agreement with experimental results when fitting the curve with the value of the virtual barrier 30 meV.

关键词： Quantum dots Photoluminescence Virtual barrier

Modeling the redshift and energy distributions of fast radio bursts

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Research in Astronomy and Astrophysics 2017年第2期17卷 22-28页

作者： Xiao-Feng Cao Ming Xiao Fei Xiao department of Physics and Engineering Hubei University of Education Wuhan 430205 China

Abstract Fast radio bursts （FRBs） are one of the most mysterious astronomical phenomena nowadays. The identification of their origin requires more observations in the future and, importantly, deep un- derstandings of the existing observational data. By fitting the redshift and energy distributions of 15 Parkes FRBs, we try to derive their intrinsic energy function and the cosmic evolution of their burst rates. Specifically, while the energy function is assumed as usual to have a single-power-law form, the burst rates are considered to be proportional to the cosmic star formation rates by a redshift-dependent coefficient. Some plausible fittings are obtained, which indicate the power-law assumptions are feasible and effective. The values of the power-law indices could be used to independently constrain candidate FRB models, although parameter degeneracies still exist.

关键词： radio continuum general

Exosome-transported IncRNA H19 regulates insulin-like growth factor-1 via the H19/let-7a/insulin-like growth factor-1 receptor axis in ischemic stroke

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Neural Regeneration Research 2023年第6期18卷 1316-1320页

作者： Jue Wang Bin Cao Yan Gao Yu-Hua Chen Juan Feng department of Neurology Shengjing Hospital of China Medical UniversityShenyangLiaoning ProvinceChina department of Developmental Cell Biology Key Laboratory of Cell BiologyMinistry of Public Healthand Key Laboratory of Medical Cell BiologyMinistry of EducationChina Medical UniversityShenyangLiaoning ProvinceChina

LncRNA(long non-coding RNA) H19 is a transcript of the H19 gene that is expressed during *** previously discove red a role for circular lncRNA H19 in the onset and prognosis of cerebral ischemic *** this study,we used serum from patients with ischemic stroke,and mouse and cell culture models to elucidate the roles of plasma and neuronal exosomes in the regulatory effect of lncRNA H19 on insulin-like growth factor-1 and its mechanism in ischemic stroke,using western blotting,quantitative real-time polymerase chain reaction,and enzyme-linked immunosorbent *** exosomal IncRNA H19 was negatively associated with blood levels of insulin-like growth factor-1 in samples from patients with cerebral ischemic *** a mouse model,levels of exosomal IncRNA H19 were positively correlated with plasma and cerebral lncRNA *** a cell co-culture model,we confirmed that IncRNA H19 was transported from neuro ns to astrocytes by exosomes to induce downregulation of insulin-like growth factor-1 through the H19/let-7 a/insulin-like growth factor-1 receptor *** study provides the first evidence for the transpo rtation of IncRNA H19 by exosomes and the relationship between IncRNA H19 and insulinlike growth factor-1.

关键词： cerebral ischemia exosomes H19 insulin-like growth factor-1 insulin-like growth factor 1 receptor ischemic stroke long non-coding RNA