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npj Computational Materials 2022年第1期8卷 2419-2433页

作者： Joydeep Munshi Alexander Rakowski Benjamin H.Savitzky steven e.zeltmann Jim Ciston Matthew Henderson Shreyas Cholia Andrew M.Minor Maria K.Y.Chan Colin Ophus Center for Nanoscale Materials Argonne National LaboratoryArgonne DrWoodridge60517ILUSA National Center for electron Microscopy Molecular FoundryLawrence Berkeley National Laboratory1 Cyclotron RoadBerkeley94720CAUSA Department of Materials Science and engineering University of California BerkeleyBerkeley94720CAUSA Scientific Data Division Lawrence Berkeley National Laboratory1 Cyclotron RoadBerkeley94720CAUSA

A fast,robust pipeline for strain mapping of crystalline materials is important for many technological *** electron nanodiffraction allows us to calculate strain maps with high accuracy and spatial resolutions,but this technique is limited when the electron beam undergoes multiple ***-learning methods have the potential to invert these complex signals,but require a large number of training *** implement a Fourier space,complex-valued deep-neural network,FCU-Net,to invert highly nonlinear electron diffraction patterns into the corresponding quantitative structure factor ***-Net was trained using over 200,000 unique simulated dynamical diffraction patterns from different combinations of crystal structures,orientations,thicknesses,and microscope parameters,which are augmented with experimental *** evaluated FCU-Net against simulated and experimental datasets,where it substantially outperforms conventional analysis *** code,models,and training library are open-source and may be adapted to different diffraction measurement problems.

关键词： valued adapted crystalline

Oligodendroglial heterogeneity in health,disease,and recovery:deeper insights into myelin dynamics

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Neural Regeneration Research 2025年第11期20卷 3179-3192页

作者： Pieter-Jan Serneels Julie D.De Schutter Lies De Groef Lieve Moons steven Bergmans KU Leuven Leuven Brain InstituteDepartment of BiologyAnimal Physiology and Neurobiology DivisionNeural Circuit Development&Regeneration Research GroupLeuvenBelgium KU Leuven Leuven Brain InstituteDepartment of BiologyAnimal Physiology and Neurobiology DivisionCellular Communication&Neurodegeneration Research GroupLeuvenBelgium

Decades of research asserted that the oligodendroglial lineage comprises two cell types:oligodendrocyte precursor cells and ***,recent studies employing single-cell RNA sequencing techniques have uncovered novel cell states,prompting a revision of the existing *** forward,the oligodendroglial lineage should be delineated into five distinct cell states:oligodendrocyte precursor cells,committed oligodendrocyte precursor cells,newly formed oligodendrocytes,myelin-forming oligodendrocytes,and mature *** new classification system enables a deeper understanding of the oligodendroglia in both physiological and pathological *** this uniform terminology will facilitate comparison and integration of data across ***,including the consolidation of findings from various demyelinating models,is essential to better understand the pathogenesis of demyelinating ***,comparing injury models across species with varying regenerative capacities can provide insights that may lead to new therapeutic strategies to overcome remyelination ***,by standardizing terminology and synthesizing data from diverse studies across different animal models,we can enhance our understanding of myelin pathology in central nervous system disorders such as multiple sclerosis,Alzheimer's disease,and amyotrophic lateral sclerosis,all of which involve oligodendroglial and myelin dysfunction.

关键词： animal models demyelination fish mammals multiple sclerosis myelin neurodegeneration oligodendrocytes oligodendroglial lineage remyelination

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Seven possible states of geospatial data with respect to map projection and definition: a novel pedagogical device for GIS education

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Geo-Spatial Information Science 2018年第4期21卷 288-293页

作者： steven e.Greco Department of Human ecology University of CaliforniaDavisCAUSA

Conceptually,the theory and implementation of“map projection”in geographic information system(GIS)technology is difficult to comprehend for most introductory students and novice *** this difficulty is the concept of a“map projection file”that defines map projection parameters of geo-spatial *** problem of the“missing projection file”appears ubiquitous for all users,especially in practice where data is widely *** common problem is inadvertent misapplication of the“Define Projection”tool that can result in a GIS dataset with an incorrectly defined map projection *** education should provide more guidance in differentiating the concepts of map projection versus projection files by increasing understanding and minimizing common errors.A novel pedagogical device is introduced in this paper:the seven possible states of GIS data with respect to map projection and *** seven possible states are:(1)a projected coordinate system(PCS)that is correctly defined,(2)a PCS that is incorrectly defined,(3)a PCS that is undefined,(4)a geographic coordinate system(GCS)that is correctly defined,(5)a GCS that is incorrectly defined,(6)a GCS that is undefined,and(7)a *** created automated troubleshooting tools to determine a missing map projection file are discussed.

关键词： GIS education map projection error map projection file define projection

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亚洲高山流域千年尺度地表剥蚀的制约因素

中国科学:地球科学 2025年第1期 75-94页

作者：杨业 steven A.BINNIe 徐胜刘丛强 Tibor J.DUNAI 天津大学地球系统科学学院表层地球系统科学研究院 Institute of Geology and Mineralogy University of Cologne

本研究利用前人1233个亚洲高山流域沉积物宇宙成因核素10Be数据统一计算了地表剥蚀速率,以约束构造、气候和地形如何影响和控制地表剥蚀过程.基于高程数据逐个像元的核素产率,使用蒙特卡洛模拟方法重新计算了10Be流域剥蚀速率.剥蚀速率... 详细信息

本研究利用前人1233个亚洲高山流域沉积物宇宙成因核素10Be数据统一计算了地表剥蚀速率,以约束构造、气候和地形如何影响和控制地表剥蚀过程.基于高程数据逐个像元的核素产率,使用蒙特卡洛模拟方法重新计算了10Be流域剥蚀速率.剥蚀速率变化范围从（7.4±0.7）mm ka-1（1σ;青藏高原内部）到（9,646744+777）mm ka-1（1σ;青藏高原南部）跨四个数量级,中位数为186mm ka-1.逐个像元计算的核素产率与传统模型使用质心坐标和平均高程计算的核素产率相比,后者96.6%核素产率被低估,其中高程差越大越被低估.两种方法计算的产率偏差可达40%,究其原因可能是流域高程分布不均和核素产率随海拔和纬度呈非线性变化.通过量化地表剥蚀速率与构造、气候、地形和岩性之间的相关性将有助于推演未知流域的剥蚀速率.从局部小尺度分析,亚热带台湾岛地区剥蚀速率可能主要受降水和新构造驱动的山体滑坡影响,而降水变化范围较窄的青藏高原东部的剥蚀速率主要受控于地形;冰川覆盖的高原地区剥蚀速率受冰川作用影响,如帕米尔、青藏高原内部和南部地区;青藏高原内部剥蚀速率较低是因为较低的降水和较高的侵蚀基准面,从而限制了河流的下切和地表起伏度演化.与局部小尺度强调单一主控因素不同,本研究对亚洲高山流域宏观大尺度进行量化分析发现:（1）地形指标（包括坡度、地形起伏度和河道陡峭指数）与剥蚀速率在千年尺度呈现一致的幂函数关系,而非简单线性;（2）剥蚀速率与气候（包括与海拔相关的降水、温度和植被覆盖度）和新构造活动（地震核密度分布）呈近似幂函数关系,为次要控制因素;（3）岩性与剥蚀速率没有明显的相关性,可能受限于流域复杂的岩性混合和低分辨率的可侵蚀指数数据.

关键词： 10Be剥蚀速率气候变化构造抬升地形梯度亚洲高山流域

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DNA alkylation promoted by an electron-rich quinone methide intermediate

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Frontiers of Chemical Science and engineering 2016年第2期10卷 213-221页

作者： Chengyun Huang steven e. Rokita Department of Chemistry and Biochemistry University of Maryland College Park MD 20742 USA Sichuan Institute of Geological engineering Investigation Chengdu 610072 China Department of Chemistry Johns Hopkins University Baltimore MD 21218 USA

Biological application of conjugates derived from oligonucleotides and quinone methides have pre- viously been limited by the slow exchange of their covalent self-adducts and subsequent alkylation of target nucleic acids. To enhance the rates of these processes, a new quinone methide precursor with an electron donating substituent has been prepared. Additionally, this substi- tuent has been placed para to the nascent exo-methylene group of the quinone methide for maximum effect. A conjugate made from this precursor and a 5＇-aminohex- yloligonucleotide accelerates formation of its reversible self-adduct and alkylation of its complementary DNA as predicted from prior model studies.

关键词： quione methide DNA alkylation reversible covalent reaction bioconjugation target-directed modification of nucleic acids

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Asian Journal of Andrology 2012年第1期14卷 136-137页

作者： Andrea A Chan steven e Canfield Run Wang Division of Urology University of Texas Medical School at Houston Houston TX 77030 USA Department of Urology University of Texas MD Anderson Cancer Center Houston TX 77030 USA

The Scandinavian Prostate Cancer Group- 4 recently reported the long-term survival benefit in men who were randomized to radical prostatectomy versus men watchful waiting for localized prostate cancer.1 The authors have now presented the companion article that updates the long-term quality of life evaluation in these men.2 Given the excellent prognosis of patients with early stage prostate cancer, the impact of therapy on patient＇s quality of life is a significant factor in the optimal management of this disease.

关键词： Health-related quality of life Scandinavian patients radical prostatectomy watchful waiting

A cross-analysis framework formulti-source volunteered, crowdsourced, and authoritative geographic information: The case study of volunteered personal traces analysis against transport network data

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Geo-Spatial Information Science 2018年第3期21卷 257-271页

作者： Gloria Bordogna steven Capelli Daniele e.Ciriello Giuseppe Psaila CNR IReA MilanoItaly DISCo Universitádegli studi di Milano BicoccaSesto San GiovanniItaly DIGIP University of BergamoDalmineItaly

The paper discusses the need of a high-level query language to allow analysts,geographers and,in general,non-programmers to easily cross-analyze multi-source VGI created by means of apps,crowd-sourced data from social networks and authoritative geo-referenced data,usually represented as JSON data sets(nowadays,the de facto standard for data exported by social networks).Since an easy to use high-level language for querying and manipulating collections of possibly geo-tagged JSON objects is still unavailable,we propose a truly declarative language,named J-CO-QL,that is based on a well-defined execution model.A plug-in for a GIS permits to visualize geo-tagged data sets stored in a NoSQL database such as MongoDB;furthermore,the same plug-in can be used to write and execute J-CO-QL queries on those *** paper introduces the language by exemplifying its operators within a real study case,the aim of which is to understand the mobility of people in the neighborhood of Bergamo ***-analysis of data about transportation networks and VGI from travelers is performed,by means of J-CO-QL language,capable to manipulate and transform,combine and join possibly geo-tagged JSON objects,in order to produce new possibly geo-tagged JSON objects satisfying users’needs.

关键词： Cross-analysis framework comparing VGI crowd-sourced and authoritative geographical data JSON data-sets declarative query language heterogeneous data-sets

Metalorganic chemical vapor deposition of InN quantum dots and nanostructures

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Light(Science & Applications) 2021年第8期10卷 1409-1420页

作者： Caroline e.Reilly Stacia Keller Shuji Nakamura steven P.DenBaars Materials University of CaliforniaSanta BarbaraCA 93106USA electrical and Computer engineering University of CaliforniaSanta BarbaraCA 93106USA

Using one material system from the near infrared into the ultraviolet is an attractive goal,and may be achieved with(ln,AI,Ga)***Ⅲ-N material system,famous for enabling blue and white solid-state lighting,has been pushing towards longer wavelengths in more recent *** a bandgap of about 0.7 eV,InN can emit light in the near infrared,potentially overlapping with the part of the electromagnetic spectrum currently dominated byⅢ-As andⅢ-P *** has been the case in these otherⅢ-V material systems,nanostructures such as quantum dots and quantum dashes provide additional benefits towards optoelectronic *** the case of InN,these nanostructures have been in the development stage for some time,with more recent developments allowing for InN quantum dots and dashes to be incorporated into larger device *** review will detail the current state of metalorganic chemical vapor deposition of InN nanostructures,focusing on how precursor choices,crystallographic orientation,and other growth parameters affect the *** optical properties of InN nanostructures will also be assessed,with an eye towards the fabrication of optoelectronic devices such as light-emitting diodes,laser diodes,and photodetectors.

关键词： optoelectronic quantum chemical

Targeting duplex DNA with the reversible reactivity of quinone methides

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Signal Transduction and Targeted Therapy 2016年第1期1卷 101-105页

作者： Chengyun Huang Yang Liu steven e Rokita Department of Chemistry and Biochemistry University of MarylandCollege ParkMDUSA Chengdu Integrated Testing Center of Rocks and Ores ChengduSichuanChina National Institutes for Food and Drug Control BeijingChina Department of Chemistry Johns Hopkins UniversityBaltimoreMDUSA.

DNA alkylation and crosslinking remains a common and effective strategy for anticancer chemotherapy despite its infamous lack of *** a reactive group to a sequence-directing component has the potential to enhance target selectivity but may suffer from premature degradation or the need for an external signal for ***,quinone methide conjugates may be employed if they form covalent but reversible adducts with their sequence directing *** resulting self-adducts transfer their quinone methide to a chosen target without an external signal and avoid off-target reactions by alternative intramolecular *** transfer is shown to depend on the nature of the quinone methide and the sequencedirecting ligand in applications involving alkylation of duplex DNA through a triplex recognition *** required an electron-rich derivative that enhanced the stability of the transient quinone methide intermediate and a polypyrimidine strand of DNA to associate with its cognate polypurine/polypyrimidine *** quinone methide conjugates with peptide nucleic acids were capable of quinone methide transfer from their initial precursor but not from their corresponding *** active peptide nucleic acid derivatives were highly selective for their complementary target.

关键词： reversible alkylation reactivity

Design of a water curtain to reduce accumulations of float coal dust in longwall returns

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International Journal of Mining Science and Technology 2020年第4期30卷 443-447页

作者： Clara e.Seaman Michael R.Shahan Timothy W.Beck steven e.Mischler National Institute for Occupational Safety and Health Pittsburgh Mining Research DivisionPittsburghPA 15236USA

Accumulation of float coal dust(FCD)in underground mines is an explosion hazard that affects all underground coal mine *** this hazard is addressed by the application of rock dust,inadequate rock dusting practices can leave miners exposed to an explosion *** at the National Institute for Occupational Safety and Health(NIOSH)have focused on developing a water curtain that removes FCD from the airstream,thereby reducing the buildup of FCD in mine *** this study,the number and spacing of the active sprays in the water curtain were varied to determine the optimal configuration to obtain peak knockdown efficiency(Ke)while minimizing water consumption.

关键词： Float coal dust Longwall Water spray Knockdown efficiency explosion prevention Dust control

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