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Molecular Plant 2018年第1期11卷 31-46页

作者： William j. barnes Charles T. Anderson Department of Biology Center for Ugnocellulose Structure and Formation The Pennsylvania State University University Park PA 16802 USA

Plant cell walls contain elaborate polysaccharide networks and regulate plant growth, development, mechanics, cell-cell communication and adhesion, and defense. Despite conferring rigidity to support plant structures, the cell wall is a dynamic extracellular matrix that is modified, reorganized, and degraded to tightly control its properties during growth and development. Far from being a terminal carbon sink, many wall polymers can be degraded and recycled by plant cells, either via direct re-incorporation by trans- glycosylation or via internalization and metabolic salvage of wall-derived sugars to produce new precur- sors for wall synthesis. However, the physiological and metabolic contributions of wall recycling to plant growth and development are largely undefined. In this review, we discuss long-standing and recent evi- dence supporting the occurrence of cell-wall recycling in plants, make predictions regarding the develop- mental processes to which wall recycling might contribute, and identify outstanding questions and emerging experimental tools that might be used to address these questions and enhance our understanding of this poorly characterized aspect of wall dynamics and metabolism.

关键词： Plant cell walls wall degradation wall recycling wall biosynthesis

Time scales and length scales in magma ?ow pathways and the origin ofmagmatic Ni-Cu-PGE ore deposits

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Geoscience Frontiers 2019年第1期10卷 77-87页

作者： Stephen j.barnes jesse C.Robertson CSIRO Mineral Resources

Ore forming processes involve the redistribution of heat, mass and momentum by a wide range of processes operating at different time and length scales. The fastest process at any given length scale tends to be the dominant control. Applying this principle to the array of physical processes that operate within magma flow pathways leads to some key insights into the origins of magmatic Ni-Cu-PGE sulfide ore deposits. A high proportion of mineralised systems, including those in the super-giant Noril'sk-Talnakh camp, are formed in small conduit intrusions where assimilation of country rock has played a major role. Evidence of this process is reflected in the common association of sulfides with varitextured contaminated host rocks containing xenoliths in varying stages of assimilation. Direct incorporation of S-bearing country rock xenoliths is likely to be the dominant mechanism for generating sulfide liquids in this setting. However, the processes of melting or dissolving these xenoliths is relatively slow compared with magma flow rates and, depending on xenolith lithology and the composition of the carrier magma, slow compared with settling and accumulation rates. Chemical equilibration between sulfide droplets and silicate magma is slower still, as is the process of dissolving sulfide liquid into initially undersaturated silicate magmas. Much of the transport and deposition of sulfide in the carrier magmas may occur while sulfide is still incorporated in the xenoliths, accounting for the common association of magmatic sulfide-matrix ore breccias and contaminated "taxitic" host rocks. Effective upgrading of so-formed sulfide liquids would require repetitive recycling by processes such as reentrainment, back flow or gravity flow operating over the lifetime of the magma transport system as a whole. In contrast to mafic-hosted systems, komatiite-hosted ores only rarely show an association with externally-derived xenoliths, an observation which is partially due to the pre

关键词： Magmatic ore deposits Assimilation Intrusions Nickel Norilsk Komatiites

Rethinking Polyp Segmentation from An Out-ofdistribution Perspective

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Machine Intelligence Research 2024年第4期21卷 631-639页

作者： Ge-Peng ji jing Zhang Dylan Campbell Huan Xiong Nick barnes Australian National University Canberra 8105Australia Mohamed bin Zayed University of Artificial Intelligence Abu Dhabi 999041UAE

Unlike existing fully-supervised approaches,we rethink colorectal polyp segmentation from an out-of-distribution perspective with a simple but effective self-supervised learning *** leverage the ability of masked autoencoders-self-supervised vision transformers trained on a reconstruction task-to learn in-distribution representations,here,the distribution of healthy colon *** then perform out-of-distribution reconstruction and inference,with feature space standardisation to align the latent distribution of the diverse abnormal samples with the statistics of the healthy *** generate per-pixel anomaly scores for each image by calculating the difference between the input and reconstructed images and use this signal for out-of-distribution(i.e.,polyp)*** results on six benchmarks show that our model has excellent segmentation performance and generalises across *** code is publicly available at https://***/GewelsjI/Polyp-OOD.

关键词： Polyp segmentation anomaly segmentation out-of-distribution segmentation masked autoencoder abdomen.

Editorial for Special Issue on Multi-modal Representation Learning

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Machine Intelligence Research 2024年第4期21卷 615-616页

作者： Deng-Ping Fan Nick barnes Ming-Ming Cheng Luc Van Gool Nankai University China&ETH ZirichSwitzerland Australian National University Australia Nankai University China ETH Zirich Switzerland

The past decade has witnessed the impressive and steady development of single-modal AI technologies in several fields,thanks to the emergence of deep *** studied,however,is multi-modal AI-commonly considered the next generation of AI-which utilizes complementary context concealed in different-modality inputs to improve *** naturally learn to form a global concept from multiple modalities(i.e.,sight,hearing,touch,smell,and taste),even when some are incomplete or ***,in addition to the two popular modalities(vision and language),other types of data such as depth,infrared information,and events are also important for multi-modal learning in real-world scenes.

关键词： modal utilize incomplete

Zircon age depth-profiling sheds light on the early Caledonian evolution of the Seve Nappe Complex in west-central j?mtland

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Geoscience Frontiers 2022年第2期13卷 460-470页

作者： Katarzyna Walczak Christopher j.barnes jaroslaw Majka David G.Gee Iwona Klonowska AGH University of Science and Technology Faculty of GeologyGeophysics and Environmental Protectional.Mickiewicza 3030-059 KrakówPoland Uppsala University Department of Earth SciencesVillavagen 16752-36 UppsalaSweden

The Scandinavian Caledonides comprise nappe stacks of far-travelled allochthons that record closure of the Iapetus Ocean and subsequent continental collision of Baltica and *** Seve Nappe Complex(SNC)of the Scandinavian Caledonides includes relics of the outermost Baltoscandian passive margin that were subducted to mantle *** earliest of the deep subduction events has been dated to ca.500-480 *** of this event has been reported from the northern exposures of the *** south in the central and southern segments of the SNC,(ultra)high-pressure rocks have yielded younger ages in the range of ca.470-440 *** study provides the first record of the early Caledonian event in the southern *** evidence has been obtained by depth profiling of zircon grains that were extracted from the Tv?r?klumparna microdiamond-bearing *** zircon grains preserve eclogite facies overgrowths that crystallized at 482.6±3.8 Ma.A second,chemically-distinct zircon overgrowth records granulite facies metamorphism at 439.3±3.6 Ma,which corroborates previous geochronological evidence for granulite facies metamorphism at this *** on these results,we propose that the entire outer margin of Baltica was subducted in the late Cambrian to early Ordovician,but the record of this event may be almost entirely eradicated in the vast majority of lithologies by pervasive late Ordovician to early Silurian metamorphism.

关键词： Caledonian Orogeny Seve Nappe Complex Zircon geochronology Depth profiling HP/UHP metamorphism Double dunking

Charge qubits based on ultra-thin topological insulator films

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Frontiers of physics 2024年第3期19卷 71-81页

作者： Kexin Zhang Hugo V.Lepage Ying Dong Crispin H.W.barnes Research Center for Quantum Sensing Intelligent Perception Research InstituteZhejiang LabHangzhou 311121China Cavendish Laboratory Department of PhysicsUniversity of CambridgeCambridge CB30HEUnited Kingdom

We study how to use the surface states in a Bi2Se3 topological insulator ultra-thin film that are affected by finite size effects for the purpose of quantum *** demonstrate that:(i)surface states under the finite size effect can effectively form a two-level system where their energy levels lie in between the bulk energy gap and a logic qubit can be constructed,(ii)the qubit can be initialized and manipulated using electric pulses of simple forms,(iii)two-qubit entanglement is achieved through a√SWAP operation when the two qubits are in a parallel setup,and(iv)alternatively,a Floquet state can be exploited to construct a qubit and two Floquet qubits can be entangled through a Controlled-NOT *** Floquet qubit offers robustness to background noise since there is always an oscillating electric field applied,and the single qubit operations are controlled by amplitude modulation of the oscillating field,which is convenient experimentally.

关键词： topological insulator quantum computing nanodevices

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慢性阻塞性肺疾病的治疗前景

中华医学杂志 2006年第41期86卷 2884-2886页

作者： Peter j barnes 英国伦敦皇家学院国际心肺研究所

目前治疗慢性阻塞性肺疾病(COPD)的方法非常有限,尚无能够减缓病情发展和功能损伤的有效措施.因此,许多制药公司都纷纷致力于探索并研发新的、更有效的、能从根本上控制疾病进展的药物[1,2]。

关键词：慢性阻塞性肺疾病治疗前功能损伤病情发展制药公司疾病进展前治疗

金属元素比值在镁铁质-超镁铁质侵入岩的铂族元素矿床勘探中的应用

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地质地球化学 1991年第4期19卷 17-20页

作者： S.j.barnes 李松辽宁有色勘查大队

即使岩浆中可能含有足够在侵入体中形成矿床的铂族元素,然而由于硫化物起到了铂族元素集聚体的作用,因此岩浆在它现在的位置定位以前就不应该经历硫化物的分凝作用。先期硫化物的分凝作用将把铀族元素从岩浆中提取出来并在别的位置(可... 详细信息

即使岩浆中可能含有足够在侵入体中形成矿床的铂族元素,然而由于硫化物起到了铂族元素集聚体的作用,因此岩浆在它现在的位置定位以前就不应该经历硫化物的分凝作用。先期硫化物的分凝作用将把铀族元素从岩浆中提取出来并在别的位置(可能在深部)淀积下来。假如先期硫化物的分凝作用没有把铂族元素从岩浆中提取出来,那么它们就有可能在侵入体中早期硫化物形成的位置富集。由于铂族元素在硫化物中具有此Ni和Cu高得多的分配系数,所以硫化物的分凝作用会强烈地影响Ni和Cu与铂族元素的比值。因此,为了判断某一侵入体中是否有可能赋存有铂族元素矿床,应该对冷凝边上Ni和Cu与铂族元素的比值加以研究。如果冷凝岩中铂族元素相对于Ni和Cu而言没有被贫化,那么该侵入体中就可能赋存铂族元素矿床。为了对侵入体中富集的铂族元素进行定位,可以利用横穿地层剖面岩石的Ni和Cu与铂族元素的比值,来寻找硫化物最初达到饱和的位置。然而,由于Ni和Cu与铂族元素的比值还受橄榄石和铬铁矿结晶作用的影响而使情况变得复杂化。为了消除橄榄石和铬铁矿对铂族元素和Ni迁移的影响,有必要考虑Pd/Ir或Pd/Rh或Pd/Pt与Ni/Cu的比值关系。

关键词：铂矿床勘探金属元素比值侵入岩

An Elevated Perspective: Dyke-Related Fracture Networks Analysed with Uav Photogrammetry

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Acta Geologica Sinica(English Edition) 2016年第S1期90卷 54-55页

作者： Gregory DERING Steven MICKLETHWAITE Stephen j.barnes Marco FIORENTINI Alexander CRUDEN Eric TOHVER School of Earth Sciences ARC Centre of Excellence for Core to Crust Fluid Systems University of Western Australia Mineral Resources Flagship CSIRO School of Earth Atmosphere and Environment Monash University

An abundance of data from seismic and geodetic monitoring has provided new insight into dyke propagation and emplacement *** studies show that faulting and fracturing is part of the magma

关键词： rock An Elevated Perspective Dyke-Related Fracture Networks Analysed with Uav Photogrammetry

加拿大Quetico沉积变质带中亚固相浅色体与深熔混合岩浅色体的时间及成分的差异

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地质科技情报 1989年第3期8卷 19-25页

作者： E.W.Sawyer S.-j.barnes 王河锦

Quetico沉积变质带中的混合岩含有两类浅色体:1.顺层浅色体:它们是在变形作用与前进变质作用中产生的.与 Quetico沉积变质物相比较,这些浅色体富含sio_2、Sr和Eu,而贫Tio_2、Fe_2O_3、MgO、Cs、Rb、REE、Sc、Th、Zr及Hf.2.切层浅色体:... 详细信息

Quetico沉积变质带中的混合岩含有两类浅色体:1.顺层浅色体:它们是在变形作用与前进变质作用中产生的.与 Quetico沉积变质物相比较,这些浅色体富含sio_2、Sr和Eu,而贫Tio_2、Fe_2O_3、MgO、Cs、Rb、REE、Sc、Th、Zr及Hf.2.切层浅色体:它们形成于区域性褶皱事件之后,此时变质温度正值其峰值.与Quetico沉积变质物相比,这些浅色体富含Rb、Ba、Sr和Eu,且LREE、Th、Zr和Hf的含量变化较大.顺层浅色体是由一种称为构造分结作用的亚固相过程所形成的.这种由应力导致的块体转移过程于Quetico沉积变质物被埋藏而发生变形时就己开始,并在岩石经受应力和非均质化的过程中一直都在持续进行,亚固相浅色体的成分是与在压溶作用下经主岩活化作用而来的石英和长石相一致的.切层浅色体是在变质带的抬升过程中由Quetico沉积变质岩的部分熔融所形成的.在浅色体侵位过程中,由于结晶分馏作用而使深熔浅色体的成分有很大变化.有些深熔浅色体保存了初始熔体的成分,并具有平滑的REE型式,而具负EU异常的那些则代表分馏熔体,其它具有正EU异常的深熔浅色体则代表长石与所俘获对熔体的聚集.

关键词： Quetico 沉积变质混合岩初始熔体变质作用切层侵位变质带变形作用部分熔融