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Observing the collapse of super-Bloch oscillations in strong-driving photonic temporal lattices

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Advanced Photonics 2024年第4期6卷 14-24页

作者： Xinyuan Hu Shulin Wang chengzhi Qin Chenyu Liu Lange Zhao Yinglan Li Han Ye Weiwei Liu Stefano Longhi Peixiang Lu Bing Wang Huazhong University of Science and Technology School of Physics Wuhan National Laboratory for Optoelectronics Wuhan Institute of Technology Hubei Key Laboratory of Optical Information and Pattern Recognition Politecnico di Milano Dipartimento di Fisica IFISC (UIB-CSIC) Instituto de Fisica Interdisciplinary Sistemas Complejos

Super-Bloch oscillations(SBOs) are amplified versions of direct current(dc)-driving Bloch oscillations realized under the detuned dc-and alternating current(ac)-driving electric fields. A unique feature of SBOs is the coherent oscillation inhibition via the ac-driving renormalization effect, which is dubbed as the collapse of SBOs. However, previous experimental studies on SBOs have only been limited to the weak ac-driving regime, and the collapse of SBOs has not been observed. Here, by harnessing a synthetic temporal lattice in fiber-loop systems, we push the ac-field into a strong-driving regime and observe the collapse of SBOs, which manifests as the oscillation-trajectory localization at specific ac-driving amplitudes and oscillation-direction flip by crossing collapse points. By adopting arbitrary-wave ac-driving fields, we also realize generalized SBOs with engineered collapse conditions. Finally, we exploit the oscillation-direction flip features to design tunable temporal beam routers and splitters. We initiate and demonstrate the collapse of SBOs, which may feature applications in coherent wave localization control for optical communications and signal processing.

关键词： Electric fields Optical modulators Phase modulation Bessel functions Optical coherence Polarization Pulse signals Solids Physical coherence Signal processing

Remote sensing of quality traits in cereal and arable production systems:A review

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The Crop Journal 2024年第1期12卷 45-57页

作者： Zhenhai Li chengzhi Fan Yu Zhao Xiuliang Jin Raffaele Casa Wenjiang Huang Xiaoyu Song Gerald Blasch Guijun Yang James Taylor Zhenhong Li College of Geodesy and Geomatics Shandong University of Science and TechnologyQingdao 266590ShandongChina Key Laboratory of Quantitative Remote Sensing in Ministry of Agriculture and Rural Affairs Information Technology Research CenterBeijing Academy of Agriculture and Forestry SciencesBeijing 100097China Institute of Crop Sciences Chinese Academy of Agricultural Sciences/Key Laboratory of Crop Physiology and EcologyMinistry of Agriculture and Rural AffairsBeijing 100081China DAFNE Universitàdella TusciaVia San Camillo de Lellis01100 ViterboItaly Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100094China International Maize and Wheat Improvement Center(CIMMYT) PO Box 5689Addis AbabaEthiopia ITAP Univ.MontpellierINRAEInstitut AgroMontpellier 34000France College of Geological Engineering and Geomatics Chang’an UniversityXi’an 710054ShaanxiChina

Cereal is an essential source of calories and protein for the global *** predicting cereal quality before harvest is highly desirable in order to optimise management for farmers,grading harvest and categorised storage for enterprises,future trading prices,and policy *** use of remote sensing data with extensive spatial coverage demonstrates some potential in predicting crop quality *** studies have also proposed models and methods for predicting such traits based on multiplatform remote sensing *** this paper,the key quality traits that are of interest to producers and consumers are *** literature related to grain quality prediction was analyzed in detail,and a review was conducted on remote sensing platforms,commonly used methods,potential gaps,and future trends in crop quality *** review recommends new research directions that go beyond the traditional methods and discusses grain quality retrieval and the associated challenges from the perspective of remote sensing data.

关键词： Remote sensing Quality traits Grain protein Cereal

Response Mechanisms to Flooding Stress in Mulberry Revealed by Multi-Omics Analysis

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Phyton-International Journal of Experimental Botany 2024年第2期93卷 227-245页

作者： Jingtao Hu Wenjing Chen Yanyan Duan Yingjing Ru Wenqing Cao Pingwei Xiang chengzhi Huang Li Zhang Jingsheng Chen Liping Gan College of Biology and Food Engineering Chongqing Three Gorges UniversityChongqing404100China Chongqing Three Gorges Academy of Agricultural Sciences Chongqing Three Gorges UniversityChongqing404155China

Abiotic stress,including flooding,seriously affects the normal growth and development of ***(Morus alba),a species known for its flood resistance,is cultivated worldwide for economic *** transcriptomic analysis has identified numerous differentially expressed genes(DEGs)involved in submergence tolerance in mulberry ***,a comprehensive analyses of metabolite types and changes under flooding stress in mulberry remain unreported.A non-targeted metabolomic analysis utilizing liquid chromatographytandem mass spectrometry(LC-MS/MS)was conducted to further investigate the effects of flooding stress on mulberry.A total of 1,169 metabolites were identified,with 331 differentially accumulated metabolites(DAMs)exhibiting up-regulation in response to flooding stress and 314 displaying *** enrichment analysis identified significant modifications in many metabolic pathways due to flooding stress,including amino acid biosynthesis and metabolism and flavonoid *** and DEGs are significantly enriched in the Kyoto Encyclopedia of Genes and Genomes(KEGG)pathways for amino acid,phenylpropanoid and flavonoid ***,metabolites such as methyl jasmonate,sucrose,and D-mannose 6-phosphate accumulated in mulberry leaves post-flooding ***,genes and metabolites associated with these KEGG pathways are likely to exert a significant influence on mulberry flood *** study makes a substantial contribution to the comprehension of the underlying mechanisms implicated in the adaptation of mulberry plants to submergence.

关键词： Mulberry flooding stress flavonoid biosynthesis phenylpropanoid biosynthesis

Mapk7 deletion in chondrocytes causes vertebral defects by reducing MEF2C/PTEN/AKT signaling

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Genes & Diseases 2024年第2期11卷 964-977页

作者： chengzhi Wu Hengyu Liu Dongmei Zhong Xiaoming Yang Zhiheng Liao Yuyu Chen Shun Zhang Deying Su Baolin Zhang Chuan Li Liru Tian Caixia Xu Peiqiang Su Guangdong Provincial Key Laboratory of Orthopedics and Traumatology Department of Spine SurgeryThe First Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdong 510080China Research Center for Translational Medicine The First Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdong 510080China Precision Medicine Institute The First Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdong 510080China Department of Orthopedics Renmin Hospital of Wuhan UniversityWuhanHubei 430060China Guangdong Provincial Key Laboratory of Proteomics and State Key Laboratory of Organ Failure Research School of Basic Medical SciencesSouthern Medical UniversityGuangzhouGuangdong 510515China

Mutation of the MAPK7 gene was related to human ***7 regulated the development of limb bones and skulls in ***,the role of MAPK7 in vertebral development is still *** this study,we constructed Col2a1-cre;Mapk7 f/f transgenic mouse model to delete Mapk7 in cartilage,which displayed kyphosis and ***,Mapk7 loss decreased MEF2C expression and thus activated PTEN to oppose PI3K/AKT signaling in vertebral growth plate chondrocytes,which impaired chondrocyte hypertrophy and attenuated vertebral *** vivo,systemic pharmacological activation of AKT rescued impaired chondrocyte hypertrophy and alleviated mouse vertebral defects caused by Mapk7 *** study firstly clarified the mechanism by which MAPK7 was involved in vertebral development,which might contribute to understanding the pathology of spinal deformity and provide a basis for the treatment of developmental disorders of the spine.

关键词： Chondrocyte hypertrophy Growth plate Kyphosis MAPK7 MEF2C Osteopenia PI3K/AKT PTEN

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皮肤镜辅助诊断不典型泛发性体癣一例

中国麻风皮肤病杂志 2021年第9期37卷 591-592页

作者：杨海琼董昳莅景东云吕成志大连市皮肤病医院辽宁大连116021

患者,女,24岁。面、躯干、双上肢红斑、鳞屑伴痒3个月。皮肤科查体:面部、躯干、双上肢散在分布绿豆至黄豆大红斑,上有少许白色鳞屑,部分皮损中心破损结痂。皮肤镜检查提示可能存在真菌感染,建议行真菌检查。真菌涂片镜检:菌丝阳性;真... 详细信息

患者,女,24岁。面、躯干、双上肢红斑、鳞屑伴痒3个月。皮肤科查体:面部、躯干、双上肢散在分布绿豆至黄豆大红斑,上有少许白色鳞屑,部分皮损中心破损结痂。皮肤镜检查提示可能存在真菌感染,建议行真菌检查。真菌涂片镜检:菌丝阳性;真菌培养为犬小孢子菌。诊断为体癣。经抗真菌治疗后痊愈,随访无复发。

关键词：体癣皮肤镜

多分支废弃油井层温衰减规律及注入参数对注采性能的影响

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天然气工业 2024年第2期44卷 178-187页

作者：石昌帅王成之祝效华西南石油大学机电工程学院西南石油大学地热能研究中心

利用废弃油井开发地热资源是降低地热开发成本、促进商业推广的有效措施,其中层温衰减规律对地热系统取热效果具有重要影响。为此,以废弃油井储层为研究对象,结合泰森多边形理论对储层裂缝进行了划分,建立了三维油水两相热流耦合数值模... 详细信息

利用废弃油井开发地热资源是降低地热开发成本、促进商业推广的有效措施,其中层温衰减规律对地热系统取热效果具有重要影响。为此,以废弃油井储层为研究对象,结合泰森多边形理论对储层裂缝进行了划分,建立了三维油水两相热流耦合数值模型,分析了不同储层条件与布井结构下的层温衰减规律,探究了注入参数等因素对地热注采性能的影响。研究结果表明:(1)低渗透储层抽采30年生产温度最大差值可达22.08 K,高渗透储层(1.0×10^(-13) m^(2))温度过度衰减,长年限采热效率低;(2)储层含油率与生产温度和发电功率呈正相关关系,生产30年后差值最大可达11.57 K与0.12 MW;(3)分支井沿垂直方向会形成低温波谷,层温衰减高于储层其余部分,数量增加对注采影响小;(4)注入速率与发电功率、生产温度分别呈正、负相关关系,但注入速率超过89 kg/s时不利于长年限开采。结论认为:(1)储层取热性能对初始渗透率最为敏感,注入速率与储层含油率次之,优先开发低渗透储层有利于长年限采热;(2)应利用油田地热降低稠油黏度,形成地热辅助采油模式,以实现经济效应最大化;(3)选取6支分支井与89 kg/s的注入速率可得到可观取热效果和较好的经济效益。

关键词：地热系统废弃油井泰森多边形离散裂缝网络初始含油率层温衰减取热性能多分支井

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脂联素与银屑病的研究进展

国际皮肤性病学杂志 2016年第4期42卷 222-225页

作者：鹿洪艳宋顺鹏吕成志大连市皮肤病医院银屑病专科 116021

脂肪组织不仅是一种存储过剩能量的组织，也是一个活跃的内分泌器官，可分泌多种生物活性物质，如瘦素和脂联素等，这些物质称为脂肪因子，是体内营养状态与神经内分泌-免疫系统之间相互作用的重要介质。脂肪细胞和巨噬细胞均参与释放... 详细信息

脂肪组织不仅是一种存储过剩能量的组织，也是一个活跃的内分泌器官，可分泌多种生物活性物质，如瘦素和脂联素等，这些物质称为脂肪因子，是体内营养状态与神经内分泌-免疫系统之间相互作用的重要介质。脂肪细胞和巨噬细胞均参与释放促炎症因子，如肿瘤坏死因子、白细胞介素6、白细胞介素8、单核细胞趋化蛋白1及脂肪因子（脂联素、瘦素、抵抗素等）。其中，脂联素不仅与肥胖及胰岛素抵抗有密切关系，还具有抗炎及血管保护作用。肿瘤坏死因子α和白细胞介素6等其他细胞因子可在体外抑制脂联素的产生，而脂联素可以抑制角质形成细胞和T淋巴细胞产生肿瘤坏死因子α、白细胞介素6、17、22和干扰素γ。脂联素水平与银屑病的严重程度及肿瘤坏死因子α和白细胞介素6的水平呈负相关。

关键词：银屑病脂联素受体,脂联素脂肪因子类信号传导

政策试验网络何以有效运转?——以城市生活垃圾分类政策为例

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政治学研究 2024年第3期 140-154,M0008页

作者：易承志彭洋上海交通大学国际与公共事务学院上海市200030

政策试验是理解中国创新改制与渐进发展的重要制度窗口。既有研究多局限于央地视角下政策试验的发生机制与组织模式,较少关注政策主体间的关系互动对政策结果的影响。基于政策网络理论,文章构建出“三轮六轨”制的府际网络框架,区分了... 详细信息

政策试验是理解中国创新改制与渐进发展的重要制度窗口。既有研究多局限于央地视角下政策试验的发生机制与组织模式,较少关注政策主体间的关系互动对政策结果的影响。基于政策网络理论,文章构建出“三轮六轨”制的府际网络框架,区分了中央政府、试点地区与非试点地区上位协调、示范引领与对标竞争的行动者角色,并对城市生活垃圾分类政策变迁的因果机制进行分析。研究发现,政策主体在试点的不同阶段采取差异化的行动策略来应对任务情势的变化,使得网络结构特征与政策结果相互调适。在政策试验的府际网络中,试点任务通过层层分解纵向下达给基层单位,试点地区与非试点地区以评比表彰为创新竞争的驱动力展开任务竞逐,中央则根据试验成效以强弱不同的政治势能来修正政策执行偏差。本文的边际贡献在于不仅拓展了双轨制政策试验的理论框架,丰富了网络治理视域下政府间行为互动的解释机制,也为理解中国公共政策体系的演进与发展提供了新的思路与方向。

关键词：政策试验央地互动府际网络行动者角色城市生活垃圾分类

基于卷积神经网络实现锥形束CT牙齿分割及牙位标定

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北京大学学报（医学版） 2024年第4期56卷 735-740页

作者：薄士仕高承志北京大学口腔医学院·口腔医院综合二科国家口腔医学中心国家口腔疾病临床医学研究中心口腔生物材料和数字诊疗装备国家工程研究中心北京100081 北京大学人民医院口腔科北京100044

目的:利用卷积神经网络实现基于锥形束CT(cone-beam computed tomography,CBCT)体素数据的牙齿实例分割和牙位标定。方法:本文所提出的牙齿算法包含三个不同的卷积神经网络,网络架构以Resnet为基础模块,首先对CBCT图像进行降采样,然后... 详细信息

目的:利用卷积神经网络实现基于锥形束CT(cone-beam computed tomography,CBCT)体素数据的牙齿实例分割和牙位标定。方法:本文所提出的牙齿算法包含三个不同的卷积神经网络,网络架构以Resnet为基础模块,首先对CBCT图像进行降采样,然后确定一个包含CBCT图像中所有牙齿的感兴趣区域(region of interest,ROI)。通过训练模型,ROI利用一个双分支“编码器-解码器”结构网络,预测输入数据中每个体素所对应的相关空间位置信息,进行聚类后实现牙齿的实例分割。牙位标定则通过另一个多类别分割任务设计的U-Net模型实现。随后,在原始空间分辨率下,训练了一个用于精细分割的U-Net网络,得到牙齿的高分辨率分割结果。本实验收集了59例带有简单冠修复体及种植体的CBCT数据进行人工标注作为数据库,对牙齿算法的预测结果使用实例Dice相似系数(instance Dice similarity coefficient,IDSC)用来评估牙齿分割结果,使用平均Dice相似系数(the average Dice similarity coefficient,ADSC)评估牙齿分割及牙位标定的共同结果并进行评定。结果:量化指标显示,IDSC为89.35%,ADSC为84.74%。剔除了带有修复体伪影的数据后生成了有43例样本的数据库,训练网络得到了更优良的性能,IDSC为90.34%,ADSC为87.88%。将得到的结果进行可视化分析,牙齿算法不仅可以清晰地分割出CBCT中牙齿的形态,而且可以对牙齿的分类进行准确的编号。结论:该牙齿算法不仅可以成功实现三维图像的牙齿及修复体分割,还可以准确标定所有恒牙的牙位,具有临床实用性。

关键词：卷积神经网络锥形束CT 牙齿实例分割牙位标定

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