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Recent Progress in High-speed and High Spectral Efficiency Optical Transmission Technology

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China Communications 2010年第3期7卷 24-34页

作者： zhou Xiang yu Jianjun AT＆T Labs-Research Middletown NJ 07748 USA ZTE USA Inc.NJ USA ZTE Inc. Shenzhen 518057 Guangdong Province P. R. China

Increasing the spectral efficiency and per channel data rate have historically been shown to be the most cost-effective method to meet the need of ever growing capacity demand in the core network. In this paper we review recent progress in high-speed and high-spectral-efficient optical transmission technology. We discuss spectrally efficient modulation and detection technologies that have been experimentally explored for future 100-Gb/s and above optical transmission system. Emerging methods aiming at extending system reach for noise and nonlinearity-stressed high spectral efficiency optical transmission systems have also been reviewed. We show that spectrallyefficient multilevel coding coupled with polarization multiplexing and digital coherent detection has the potential to enable 400Gb/s per channel WDM system operating with existing 50GHzspaced WDM infrastructure at a spectral efficiency of 8b/s/Hz.

关键词： optical modulation format coherent detection fiber and DSP

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不同居群蒙古扁桃的遗传多样性SRAP分析

分子植物育种 2024年第8期22卷 2583-2589页

作者：丁海麦白羽周红兵石松利内蒙古科技大学包头医学院包头014040

本研究选取5个具有代表性野生蒙古扁桃种群为研究对象,以同科近属蒙古柄扁桃种群为对照,采用SRAP分子标记方法,对珍稀濒危药用植物蒙古扁桃遗传多样性进行研究,为蒙古扁桃资源的合理保护和可持续利用提供科学的依据。用筛选出的12对SRA... 详细信息

本研究选取5个具有代表性野生蒙古扁桃种群为研究对象,以同科近属蒙古柄扁桃种群为对照,采用SRAP分子标记方法,对珍稀濒危药用植物蒙古扁桃遗传多样性进行研究,为蒙古扁桃资源的合理保护和可持续利用提供科学的依据。用筛选出的12对SRAP引物,通过优化的反应体系对60个样品进行扩增,共扩增出171个清晰可重复的条带,其中多态性条带有166条,占97.08%。在物种水平上,Nei’s基因多样度(h)0.371 1、Shannon信息指数(I)为0.546 8;种群间遗传分化系数(Gst)为0.596 4。结果显示蒙古扁桃居群的遗传变异主要存在于居群间,居群间的遗传分化程度大于居群内的,综合评价贺兰山的蒙古扁桃遗传多样性较高,应当优先保护。

关键词：蒙古扁桃柄扁桃 SRAP 遗传多样性

Fermi-level-tuned MOF-derived N-ZnO@NC for photocatalysis:A key role of pyridine-N-Zn bond

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Journal of Materials Science & Technology 2022年第17期112卷 68-76页

作者： Zheao Huang Qiancheng zhou Jieming Wang Ying yu Institute of Nanoscience and Nanotechnology College of Physical Science and TechnologyCentral China Normal UniversityWuhan 430079China

For photocatalytic materials,the composites formed by metal oxides and heteroatom-doped carbon have outstanding *** them,metal-organic framework(MOF)derived composites,usually composed of metal oxide and nitrogen-doped carbon,is not only simple to prepare,but also have far-exceeding catalytic performance than homogenous ***,the relationship between the structure and performance in the photocatalytic system is still not ***,we explored the tunable nitrogen configurations in sample N-ZnO@NC by controlling the thermal conversion of ***,through exsitu and in-situ XPS characterization,it is found that the ZnO and nitrogen-doped carbon in N-ZnO@NC are connected by C-N-Zn bond,which enhances charge separation efficiency and becomes the origin of superior photocatalytic *** calculations further reveal the influence of different Zn-bonding nitrogen configurations on the adjusting of Fermi level and electron *** study exhibits that the pyridine-N configuration in MOF-derived material is the main contributor for the improved performance and tunes Fermi level more appropriately than the pyrrolic-N,which can hold the key for future design of next-generation photocatalysts.

关键词： MOF-derived material Fermi level Pyridine-N-Zn DFT calculations Photocatalysis

Facile synthesis of gradient copolymers enabled by droplet-flow photo-controlled reversible deactivation radical polymerization

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Science China Chemistry 2021年第5期64卷 844-851页

作者： Yang zhou Shantao Han yu Gu Mao Chen State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200438China

Monomer sequence influences the properties and applications of ***,massive efforts have been made to implement sequence control of *** this work,we developed a computer-aided droplet-flow polymerization based on photo-controlled reversible-deactivation radical polymerization(photo-RDRP),enabling synthesis of gradient copolymers of tunable sequential arrangements,low dispersity and good structural fidelity from various monomers without following their intrinsic reactivities,which is a key limitation in sequence *** obtained gradient copolymers exhibit unique thermal properties and stimulus responsiveness comparing with the random and block counterparts,and their glass transition behaviour could be regulated by the gradient *** believe that the unprecedented gradient photo-RDRP based on flow synthesis opens a robust and versatile avenue to streamline the synthesis of well-defined gradient polymers,and is compatible with other polymerization mechanisms.

关键词： controlled radical polymerization photopolymerization gradient copolymer flow chemistry sequence control

k-Submodular Maximization with a Knapsack Constraint and p Matroid Constraints

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Tsinghua Science and Technology 2023年第5期28卷 896-905页

作者： Qian Liu Kemin yu Min Li Yang zhou School of Mathematics and Statistics Shandong Normal UniversityJinan 250014China

A k-submodular function is a generalization of a submodular function,its definition domain is extended from the collection of single subsets to the collection of k disjoint *** k-submodular maximization problem has a wide range of *** this paper,we propose a nested greedy and local search algorithm for the problem of maximizing a monotone k-submodular function subject to a knapsack constraint and p matroid constraints.

关键词： k-submodularity knapsack constraint matroid constraint approximation algorithm

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基于分形图案的透孔织物的设计和开发

毛纺科技 2024年第4期52卷 8-10页

作者：孙丹周蕙于颖李广莹张明月齐齐哈尔大学轻工与纺织学院黑龙江齐齐哈尔161006 齐齐哈尔大学寒区麻及制品教育部工程研究中心黑龙江齐齐哈尔161006

为了丰富花式透孔织物的花纹种类,利用平纹和透孔组织的特点,采用分形图案设计,将平纹和简单透孔组织结合,形成有规律的花式透孔组织图案,以谢尔宾斯基地毯图案作为花式透孔组织的分形图案纹样,进行花式透孔织物的组织设计、上机设计及... 详细信息

为了丰富花式透孔织物的花纹种类,利用平纹和透孔组织的特点,采用分形图案设计,将平纹和简单透孔组织结合,形成有规律的花式透孔组织图案,以谢尔宾斯基地毯图案作为花式透孔组织的分形图案纹样,进行花式透孔织物的组织设计、上机设计及工艺参数设计等,并进行试织。结果得出:采用谢尔宾斯基地毯图案作为分形图案进行纹样设计,使平纹和透孔组织形成的花式透孔组织图案更有规律性,同时纹样新颖,具有装饰性,分形图案的使用也为多组织组合形成多种类的透孔花纹图案提供了新思路。

关键词：分形图案平纹组织透孔组织组织设计谢尔宾斯基地毯图案

Bioactive materials from berberine-treated human bone marrow mesenchymal stem cells promote alveolar bone regeneration by regulating macrophage polarization

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Science China(Life Sciences) 2024年第5期67卷 1010-1026页

作者： Ziyue Qin Yanxing Han Yifei Du Yixuan Zhang Yifeng Bian Ruyu Wang Haoran Wang Fanyi Guo Hua yuan Yongchu Pan Jianliang Jin Qigang zhou yuli Wang Feng Han Yan Xu Jiandong Jiang Department of Oral and Maxillofacial Surgery The Affiliated Stomatological Hospital of Nanjing Medical UniversityNanjing 210029China Jiangsu Province Key Laboratory of Oral Diseases Nanjing Medical UniversityNanjing 210029China Jiangsu Province Engineering Research Center of Stomatological Translational Medicine Nanjing 210029China State Key Laboratoryof BioactiveSubstances andFunction of Natural Medicine Instituteof Materia MedicaChinese Academyof MedicalSciencesandPeking Union MedicalCollegeBeijing100050China Gusu school Nanjing medical universitySuzhou 215002China Key Laboratory of Cardiovascular&Cerebrovascular Medicine Drug Target and Drug Discovery CenterSchool of PharmacyNanjing Medical UniversityNanjing 211166 China Department of Orthodontics The Affiliated Stomatological Hospital of Nanjing Medical UniversityNanjing 210029China Department of Human Anatomy Research Centre for Bone and Stem CellsKey Laboratory for Aging&DiseaseThe State Key Laboratory of Reproductive MedicineNanjing Medical UniversityNanjing 211166China Department of Clinical Pharmacology School of PharmacyNanjing Medical UniversityNanjing Jiangsu211166China Department of Periodontology The Affiliated Stomatological Hospital of Nanjing Medical UniversityNanjing 210029China Department of Virology Institute of Medicinal BiotechnologyChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China

Alveolar bone regeneration has been strongly linked to macrophage polarization.M1 macrophages aggravate alveolar bone loss,whereas M2 macrophages reverse this ***(BBR),a natural alkaloid isolated and refined from Chinese medicinal plants,has shown therapeutic effects in treating metabolic *** this study,we first discovered that culture supernatant(CS)collected from BBR-treated human bone marrow mesenchymal stem cells(HBMSCs)ameliorated periodontal alveolar bone *** from the BBR-treated HBMSCs contained bioactive materials that suppressed the M1 polarization and induced the M2 polarization of macrophages in vivo and in *** clarify the underlying mechanism,the bioactive materials were applied to different animal *** discovered macrophage colony-stimulating factor(M-CSF),which regulates macrophage polarization and promotes bone formation,a key macromolecule in the *** of pure M-CSF attenuated experimental periodontal alveolar bone loss in ***-stimulating factor 1 receptor(CSF1R)inhibitor or anti-human M-CSF(M-CSF neutralizing antibody,Nab)abolished the therapeutic effects of the CS of BBR-treated ***,AKT phosphorylation in macrophages was activated by the CS,and the AKT activator reversed the negative effect of the CSF1R inhibitor or *** results suggest that the CS of BBR-treated HBMSCs modulates macrophage polarization via the M-CSF/AKT *** studies also showed that CS of BBR-treated HBMSCs accelerated bone formation and M2 polarization in rat teeth extraction ***,our findings established an essential role of BBR-treated HBMSCs CS and this might be the first report to show that the products of BBR-treated HBMSCs have active effects on alveolar bone regeneration.

关键词： berberine human bone marrow mesenchymal stem cells alveolar bone regeneration macrophage colony-stimulating factor AKT phosphorylation

A newly bio-inspired path planning algorithm for autonomous obstacle avoidance of UAV

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Chinese Journal of Aeronautics 2021年第9期34卷 199-209页

作者： Yaoming zhou yu SU Anhuan XIE Lingyu KONG School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Intelligent Robot Research Center ZHEJIANG LABZhejiang 311121China

In this paper,a bio-inspired path planning algorithm in 3 D space is *** algorithm imitates the basic mechanisms of plant growth,including phototropism,negative geotropism and *** algorithm proposed in this paper solves the dynamic obstacle avoidance path planning problem of Unmanned Aerial Vehicle(UAV)in the case of unknown environment *** with other path planning algorithms,the algorithm has the advantages of fast path planning speed and fewer route points,and can achieve the effect of low delay real-time path *** feasibility of the algorithm is verified in the Gazebo simulator based on the Robot Operating System(ROS)***,an actual UAV autonomous obstacle avoidance path planning experimental platform is built,and a UAV obstacle avoidance path planning flight test is carried out based on this actual environment.

关键词： Obstacle avoidance Path planning Plant growth ROS UAV

The role of corneal endothelium in macular corneal dystrophy development and recurrence

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Science China(Life Sciences) 2024年第2期67卷 332-344页

作者： Bi-Ning Zhang Benxiang Qi Chunxiao Dong Bin Zhang Jun Cheng Xin Wang Suxia Li Xiaoyun Zhuang Shijiu Chen Haoyun Duan Dewei Li Sujie Zhu Guoyun Li Yihai Cao Qingjun zhou Lixin Xie Eye Institute of Shandong First Medical University Qingdao Eye Hospital of Shandong First Medical UniversityQingdao 266071China State Key Laboratory Cultivation Base Shandong Provincial Key Laboratory of OphthalmologyQingdao 266071China School of Ophthalmology Shandong First Medical UniversityQingdao 250021China Department of Medicine Qingdao UniversityQingdao 266071China Eye Institute of Shandong First Medical University Eye Hospital of Shandong First Medical University(Shandong Eye Hospital)Jinan 250021China Department of Ophthalmology School of Clinical MedicineWeifang Medical UniversityWeifang 261072China Institute of Translational Medicine College of MedicineQingdao UniversityQingdao 266071China Key Laboratory of Marine Drugs of Ministry of Education Shandong Provincial Key Laboratory of Glycoscience and GlycotechnologySchool of Medicine and PharmacyOcean University of ChinaQingdao 266071China Laboratory for Marine Drugs and Bioproducts Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266071China Department of Microbiology Tumor and Cell BiologyBiomedicumKarolinska InstitutetStockholm 17177Sweden

Macular corneal dystrophy(MCD)is a progressive,bilateral stromal dystrophic disease that arises from mutations in carbohydrate sulfotransferase 6(CHST6).Corneal transplantation is the ultimate therapeutic solution for MCD ***,postoperative recurrence remains a significant *** conducted a retrospective review of a clinical cohort comprising 102 MCD patients with 124 eyes that underwent either penetrating keratoplasty(PKP)or deep anterior lamellar keratoplasty(DALK).Our results revealed that the recurrence rate was nearly three times higher in the DALK group(39.13%,9/23 eyes)compared with the PKP group(10.89%,11/101 eyes),suggesting that surgical replacement of the corneal endothelium for treating MCD is advisable to prevent postoperative *** experimental data confirmed the robust m RNA and protein expression of CHST6 in human corneal endothelium and the rodent homolog CHST5 in mouse *** knockdown of wild-type Chst5 in mouse corneal endothelium(AC^(siChst5)),but not in the corneal stroma,induced experimental MCD with similar extracellular matrix synthesis impairments and corneal thinning as observed in MCD *** carrying Chst5 point mutation also recapitulated clinical phenotypes of MCD,along with corneal endothelial *** injection of wild-type Chst5 rescued the corneal impairments in AC^(siChst5)mice and retarded the disease progression in Chst5 mutant ***,our study provides new mechanistic insights and therapeutic approaches for MCD treatment by highlighting the role of corneal endothelium in MCD development.

关键词： macular corneal dystrophy recurrence corneal endothelium keratan sulfate penetrating keratoplasty