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Deep learning tomographic reconstruction through hierarchical decomposition of domain transforms

Visual computing for Industry,Biomedicine,and Art 2022年第1期5卷 365-377页

作者： Lin Fu bruno De Man GE Research NY 12309 NiskayunaUSA

Deep learning(DL)has shown unprecedented performance for many image analysis and image enhancement ***,solving large-scale inverse problems like tomographic reconstruction remains challenging for *** problems involve non-local and space-variant integral transforms between the input and output domains,for which no efficient neural network models are readily available.A prior attempt to solve tomographic reconstruction problems with supervised learning relied on a brute-force fully connected network and only allowed reconstruction with a 128^(4)system matrix *** cannot practically scale to realistic data sizes such as 512^(4)and 512^(6)for three-dimensional *** we present a novel framework to solve such problems with DL by casting the original problem as a continuum of intermediate representations between the input and output *** original problem is broken down into a sequence of simpler transformations that can be well mapped onto an efficient hierarchical network architecture,with exponentially fewer parameters than a fully connected network would *** applied the approach to computed tomography(CT)image reconstruction for a 5124 system matrix *** work introduces a new kind of data-driven DL solver for full-size CT reconstruction without relying on the structure of direct(analytical)or iterative(numerical)inversion *** work presents a feasibility demonstration of full-scale learnt reconstruction,whereas more developments will be needed to demonstrate superiority relative to traditional reconstruction *** proposed approach is also extendable to other imaging problems such as emission and magnetic resonance *** broadly,hierarchical DL opens the door to a new class of solvers for general inverse problems,which could potentially lead to improved signal-to-noise ratio,spatial resolution and computational efficiency in various areas.

关键词： computed tomography Image reconstruction Deep learning Hierarchical

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tidal drag and westward drift of the lithosphere

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Geoscience Frontiers 2023年第6期14卷 102-116页

作者： Vincenzo Nesi Oscar bruno Davide Zaccagnino corrado Mascia carlo Doglioni Dipartimento di Matematica Guido castelnuovo Piazzale Aldo Moro5Roma 00185Italy Istituto Nazionale di Geofisica e Vulcanologia Via di Vigna Murata605Roma 00143Italy computing and Mathematical Sciences Department Caltech1200 E.California Blvd.MC 305-16Pasadena 91125CAUSA Dipartimento di Scienze della Terra Piazzale Aldo Moro5Roma 00185Italy

tidal forces are generally neglected in the discussion about the mechanisms driving plate tectonics despite a worldwide geodynamic asymmetry also observed at subduction and rift *** tidal drag could theoretically explain the westerly shift of the lithosphere relative to the underlying ***,viscosity in the asthenosphere is apparently too high to allow mechanical decoupling produced by tidal ***,we propose a model for global scale geodynamics accompanied by numerical simulations of the tidal interaction of the Earth with the Moon and the *** provide for the first time a theoretical proof that the tidal drag can produce a westerly motion of the lithosphere,also compatible with the slowing of the Earth’s rotational *** results suggest a westerly rotation of the lithosphere with a lower bound ofω≈(0.1-0.2)°/Myr in the presence of a basal effective shear viscosityη≈10^(16)Pa-s,but it may rise toω>1°/Myr with a viscosity ofη≈≤3×10^(14)Pa-s within the Low-Velocity Zone(LVZ)atop the *** faster velocity would be more compatible with the mainstream of plate motion and the global asymmetry at plate *** on these computations,we suggest that the super-adiabatic asthenosphere,being vigorously convecting,may further reduce the viscous coupling within the LVZ Therefore,the combination of solid Earth tides,ultra-low viscosity LVZ and asthenospheric polarized small-scale convection may mechanically satisfy the large-scale decoupling of the lithosphere relative to the underlying *** plate motions are explained because of lateral viscosity heterogeneities at the base of the lithosphere,which determine variable lithosphere-asthenosphere decoupling and plate interactions,hence plate tectonics.

关键词： tidal drag Plate motions Polarized plate tectonics Lithosphere-asthenosphere interaction

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m^(6)A Profile Dynamics Indicates Regulation of Oyster Development by m^(6)A-RNA Epitranscriptomes

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Genomics, Proteomics & Bioinformatics 2023年第4期21卷 742-755页

作者： Lorane Le Franc bruno Petton Pascal Favrel Guillaume Rivière Laboratoire de Biologie des Organismes et des Ecosyste`mes Aquatiques(BOREA) Muséum d’Histoire NaturelleSorbonne UniversitéUniversitéde Caen NormandieUniversitédes AntillesCNRS UMR 8067IRD14032 CaenFrance Ifremer Laboratoire des Sciences de l’Environnement MarinUMR 6539 CNRS/UBO/IRD/IfremerCentre Bretagne29280 PlouzanéFrance

The N6-methylation of RNA adenosines(N6-methyladenosine,m^(6)A)is an important regulator of gene expression with critical implications in vertebrate and insect ***,the developmental significance of epitranscriptomes in lophotrochozoan organisms remains *** methylated RNA immunoprecipitation sequencing(MeRIP-seq),we generated transcriptome-wide m^(6)A-RNA methylomes covering the entire development of the oyster from oocytes to *** RNA classes display specific m^(6)A signatures,with messenger RNAs(mRNAs)and long non-coding RNAs(lncRNAs)exhibiting distinct profiles and being highly methylated compared to transposable element(TE)*** are dynamic and correspond to the chronological steps of development(cleavage,gastrulation,organogenesis,and metamorphosis),with minimal mRNA and lncRNA methylation at the morula stage followed by a global *** m^(6)A levels are correlated with transcript levels,and shifts in methylation profiles correspond to expression *** methylated transcripts cluster according to embryo-larval stages and bear the corresponding developmental functions(cell division,signal transduction,morphogenesis,and cell differentiation).The m^(6)A level of TE transcripts is also regulated and peaks during the *** demonstrate that m^(6)A-RNA methylomes are dynamic and associated with gene expression regulation during oyster *** putative epitranscriptome implication in the cleavage,maternal-to-zygotic transition,and cell differentiation in a lophotrochozoan model brings new insights into the control and evolution of developmental processes.

关键词： RNA methylation Transcription Embryo Metamorphosis Evo-devo

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Resampling in neural networks with application to spatial analysis

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Geo-Spatial Information Science 2022年第3期25卷 413-424页

作者： bruno Póvoa Rodrigues Vinicius Francisco Rofatto Marcelo Tomio Matsuoka Talita Teles Assunção Graduate Program in Agriculture and Geospatial Information Federal University of UberlândiaMonte CarmeloBrazil Institute of Geography Federal University of UberlândiaMonte CarmeloBrazil

In developing Artificial Neural Networks(ANNs),the available dataset is split into three categories:training,validation and ***,an important problem arises:How to trust the predic-tion provided by a particular ANN?Due to the randomness related to the network itself(architecture,initialization and learning procedure),there is usually no best *** this issue,we provide a framework,which captures the randomness related to the network *** idea is to perform several training and test trials based on the Jackknife resampling *** consists of iteratively deleting a single observation each time from the sample and recomputing the ANN on the rest of the sample ***,interval prediction is available instead of point *** proposed method was applied and tested using pH,ca and P data obtained by analyzing 118 georeferenced soil *** results,based on the dataset size simulation,showed that 60%reduction in available dataset offers compatible accuracy in relation to full dataset,and therefore a higher cost of sampling in the field would not be *** re-sampling method spatially characterizes the points of greater or lesser accuracy and *** re-sampling method increased the success rate by using interval prediction instead of using the mean as the most probable *** we restrict it to the regression neural network model,the resampling method proposed can also be extended to other modern statistical tools,such as Kriging,Least Squares collocation(LSC),convolutional Neural Network(CNN),and so on.

关键词： Artificial Neural Network(ANN) data splitting resampling delete-1 Jackknife spatial analysis

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On the impact of grinding conditions in the flotation of semi-soluble salt-type mineral-containing ores driven by surface or particle geometry effects?

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International Journal of Mining Science and Technology 2023年第7期33卷 855-872页

作者： Lucas Pereira Nathalie Kupka Duong Huu Hoang bruno Michaux Sondos Saquran Doreen Ebert Martin Rudolph Helmholtz-Zentrum Dresden-Rossendorf Helmholtz Institute Freiberg for Resource TechnologyFreiberg 09599Germany Maelgwyn Mineral Services Ltd Cardiff CF244PAUnited Kingdom

Grinding and flotation processes are often studied independently, despite the well-established grinding influence on flotation performance, which affects not only particle size and thus liberation but also shape and leads to complex changes in pulp chemistry affecting the particle surface properties relevant for selective bubble attachment. Yet, no study jointly investigated these possible causes and many are limited to single mineral flotation. We relate grinding conditions to changes in pulp chemistry and particle surface properties and assess their impact on upgrading. We studied three non-sulfide ores with different feed grades and valuables: scheelite, apatite, and fluorite. These were dry-, wet-, and wet conditionedground before flotation in a laboratory mechanical cell. Results were evaluated with bulk-and particle-specific methodologies. The selectivity of the process is higher after dry grinding for the fluorite and apatite ores and irrelevant for the scheelite ore. Variations in flotation kinetics of individual particles associated to their size and shape are not sufficient to explain these results. The higher concentration of ca2+and Mg2+observed in the pulp after wet grinding, altering particle surface properties, better explains the phenomenon. Additionally, we demonstrate how particle shape impacts are system specific and related to both entrainment and true flotation.

关键词： Grinding-flotation interactions Semi-soluble salt-type minerals Geometallurgy Particle-based separation modelling Surface interactions

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Paleo-and Mesoarchean TTG-sanukitoid to high-K granite cycles in the southern São Francisco craton,SE Brazil

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Geoscience Frontiers 2022年第5期13卷 153-168页

作者： Claudio de Morisson Valeriano caio Vinicius Gabrig Turbay Henrique bruno Antonio Simonetti Monica Heilbron Samuel Moreira Bersan Rob Strachan Universidade do Estado do Rio de Janeiro Faculdade de GeologiaRua São Francisco Xavier 524/4006-BMaracanãRio de JaneiroBrazil Universidade Federal do Sul da Bahia Centro de Formação em Ciências AmbientaisPorto SeguroBahiaBrazil University of Portsmouth School of EnvironmentGeography and GeosciencesBurnaby BuildingBurnaby RoadPortsmouth PO13QLUnited Kingdom University of Notre Dame Department of Civil and Environmental Engineering and Earth Sciences46556United States

The generation of the continental crust is widely accepted to have taken place predominantly in the Archean,when TTG magmatism associated with greenstone-belt supracrustal succession development was typically followed by emplacement of high-K granites before crustal *** study focuses on the campos Gerais complex(CGC),which is an Archean granite-greenstone belt lithological association in a tectonic window located in the southwesternmost portion of the São Francisco craton(SFC).The CGC is an important segment of Paleo-to Mesoarchean continental crust to be integrated into paleogeographic reconstructions prior to the transition into the *** investigation reports field relationships,28 major and trace element compositions,U–Pb(zircon)geochronological results,and Hf and Sm–Nd isotope data for orthogneiss and amphibolite *** results indicate that the CGC records a complex Archean crustal evolution,where voluminous 2.97 Ga TTG tonalites and trondhjemites(ε_(Nd)(t)=-4.7;T_(DM)=3.24 Ga)were followed by 2.89 Ga sanukitoid tonalite production(ε_(Nd)(t)=-1.9;T_(DM)=3.02 Ga),broadly coeval with the development of the Fortaleza de Minas and Pitangui *** events are interpreted to represent the initial stage of an important subduction-accretion tectonic cycle,which ended with the emplacement of 2.82–2.81 Ga high-K leucogranites and migmatization of the TTG-sanukitoid crust,with hybrid and two-mica,peraluminous compositions(ε_(Nd)(t)=-8.0 to-8.6;T_(DM)=3.57–3.34 Ga).The presence of inherited zircons with207Pb/206Pb ages of 3.08 Ga,3.29 Ga,3.55 Ga and 3.62 Ga indicates that the Mesoarchean tectonic processes involved reworking of Meso-to Eo-archean *** TTG magmatism took place at ca.2.77 Ga represented by juvenile tonalite stocks(ε_(Nd)(t)=+1.0 to-1.5;T_(DM)=2.80–2.88 Ga)which intrude the TTG-greenstone belt *** stabilization was attained by 2.67 Ga,allowing for the emplacement of within-plate thol

关键词： Crustal evolution Sm–Nd Lu–Hf LA-ICPMS zircon U–Pb

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A perspective on potassic and ultrapotassic rocks:constraints on the Paleoproterozoic late to post-collisional event in the São Francisco paleocontinent

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Geoscience Frontiers 2022年第5期13卷 242-266页

作者： Samuel Moreira Bersan AndréDanderfer Craig Storey Henrique bruno Hugo Moreira Francisco Abreu Cristiano Lana Leonardo Gonçalves Isabela Nahas Universidade Federal de Ouro Preto Departamento de GeologiaCampus Morro do CruzeiroOuro PretoMG CEP 35400-000Brazil University of Portsmouth School of the EnvironmentGeography and GeosciencesBurnaby BuildingBurnaby RoadPortsmouth PO13QLUK Tektos Research Group UERJ-Rio de Janeiro State UniversityBrazil Sustain Geologia Belo HorizonteBrazil

The late-to post-collisional stage in orogenic systems is characterized by the coeval existence of bimodal potassic to ultrapotassic magmatic activity related to partial melting of an enriched lithospheric mantle together with crustal derived *** this paper,we present new whole rock geochemical analyses combined with zircon and titanite U–Pb and zircon Hf isotopic data from potassic to ultrapotassic rocks from six plutons that occur within the Archean Itacambira-Monte Azul block(BIMA),to discuss their petrogenesis and the tectonic implications for the São Francisco *** new U–Pb ages range from ca.2.06 Ga to 1.98 Ga and reveal long-lasting potassic magmatism within the BIMA,which is within the late-to-post-collisional stage of the São Francisco paleocontinent *** ultrapotassic rocks are compatible with a fluid-related metasomatized mantle source enriched by previous subduction events,whereas the potassic rocks are bimodal and have a transitional shoshonitic to A-type *** rocks have a hybrid nature,possible related to the mixing between the mafic potassic/ultrapotassic rocks and high temperature crustal melts of the Archean continental *** results also show an increase of within-plate signature towards the younger potassic *** participation of an important Archean crustal component in the genesis of these rocks is highlighted by the common and occasionally abundant occurrence of Archean inherited *** Hf isotopic record shows that most of the zircon inheritance has dominantly subchondriticεHf(t)values,which fits a crustal reworking derivation from a similar Eo-to Paleoarchean precursor ***,the presence of juvenile 2.36 Ga zircon inheritance in an ultrapotassic sample reveal the existence of a hidden reservoir that is somewhat similar to the described for the Mineiro Belt in southern São Francisco paleocontinent.

关键词： Late-to post-collisional Potassic-ultrapotassic rocks U–Pb dating São Francisco paleocontinent Rhyacian-Orosirian orogenic system

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Key drivers of ecosystem recovery after disturbance in a neotropical forest Long-term lessons from the Paracou experiment, French Guiana

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Forest Ecosystems 2018年第1期5卷 13-27页

作者： bruno hérault camille piponiot cirad umr ecofog (agro paristech cnrs inra université des antillesuniversité de la guyane) campus agronomique97310 kouroufrench inphb (institut national polytechnique félix houphouet boigny) yamoussoukroivorycoast université de la guyane umrecofog(agro paristech cirad cnrs inra université des antilles) campus agronomique97310 kouroufrench guianafrance

Background： Natural disturbance is a fundamental component of the functioning of tropical rainforests let to natural dynamics, with tree mortality the driving force of forest renewal. With ongoing global （i.e. land-use and climate） changes, tropical forests are currently facing deep and rapid modifications in disturbance regimes that may hamper their recovering capacity so that developing robust predictive model able to predict ecosystem resilience and recovery becomes of primary importance for decision-making：（i） Do regenerating forests recover faster than mature forests given the same level of disturbance？（ii） is the local topography an important predictor of the post-disturbance forest trajectories？（iii） Is the community functional composition, assessed with community weighted-mean functional traits, a good predictor of carbon stock recovery？（iv） How important is the climate stress （seasonal drought and/or soil water saturation） in shaping the recovery trajectory？ Methods： Paracou is a large scale forest disturbance experiment set up in 1984 with nine 6.25 ha plots spanning on a large disturbance gradient where 15 to 60% of the initial forest ecosystem biomass were removed. More than 70,000 trees belonging to ca. 700 tree species have then been censused every 2 years up today. Using this unique dataset, we aim at deciphering the endogenous （forest structure and composition） and exogenous （local environment and climate stress） drivers of ecosystem recovery in time. To do so, we disentangle carbon recovery into demographic processes （recruitment, growth, mortality fluxes） and cohorts （recruited trees, survivors）. Results： Variations in the pre-disturbance forest structure or in local environment do not shape significantly the ecosystem recovery rates. Variations in the pre-disturbance forest composition and in the post-disturbance climate significantly change the forest recovery trajectory. Pioneer-rich forests have slower recovery rates than assemblages of lat

关键词： Ecosystem modeling Tropical forests carbon fluxes Ecological resilience Climate change Amazonia

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Litter removal impacts on soil biodiversity and eucalypt plantation development in the seasonal tropics

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Journal of Forestry Research 2023年第3期34卷 735-748页

作者： Jonas Inkotte Barbara Bomfim Sarah camelo da Silva Marco bruno Xavier Valadão Márcio Gonçalves da Rosa Roberta Batista Viana Alcides Gatto Reginaldo SPereira Department of Forestry Engineering University of BrasiliaBrasíliaDistrito FederalBrazil Climate and Ecosystem Sciences Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA SESI/SENAI Social Service Industry Santa Catarina StateChapecóBrazil

The little layer of tree plantations provides primary nutrients for uptake,buff ers changes in soil moisture,and provides habitat and substrate to soil epigeic ***,this layer in eucalypt plantations is often removed to reduce fuel load during the fi re season in the Brazilian savanna(Cerrado).Therefore,it is necessary to quantify the eff ects of changes in litter dynamics on the function of these plantations,on key nutrient cycling processes and on epigeic fauna diversity and *** two adjacent stands(one juvenile and one mature),the consequences of two years of litter removal were quantifi ed as monthly litterfall,leaf and fi ne wood litter decomposition,epigeic fauna abundance and diversity,soil biogeochemical variables,and tree diameter and basal area *** litterfall rates in juvenile and mature stands did not change with litter removal over the study *** litterfall ranged from 4.1 to 4.9 Mg ha^(−1)a^(−1)in litter removal plots and from 3.9 to 4.8 Mg ha^(−1)a^(−1)in control *** wood litter decomposition was slower in litter removal plots compared to controls,while leaf decomposition rates were similar in *** years of litter removal in the juvenile stand did not aff ect topsoil biogeochemical parameters but decreased available phosphorus at 20–40 cm depth relative to *** the mature stand,total cation exchange capacity(0–20 cm)was higher in controls(6.4 cmol c dm^(−3))relative to litter removal plots(6.3 cmol c dm^(−3)),while soil moisture(0–40 cm depth)was lower in litter removal(25.45 m 3 m^(−3))compared to control plots(26 m^(3)m^(−3))in the dry season.A non-metric multidimensional scaling ordination revealed an increased homogeneity in epigeic fauna where litter was ***,decomposition,diameter increment,four soil physical parameters and fourteen chemical parameters at 0–20 and 20–40 cm depth explained the diff erences in soil epigeic fauna composition between litter removal and control p

关键词： Cerrado Nutrient cycling Soil ecology Soil epigeic fauna Plantation management

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Umbilical cord artery-derived perivascular stem cells for treatment of ovarian failure through CD146 signaling

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Signal Transduction and Targeted Therapy 2022年第8期7卷 2694-2697页

作者： Lu Xu Yanjun Yang Lingling Zhang Guijun Yan Shiyuan Li Yifan Li Yali Hu Lijun Ding bruno Péault Haixiang Sun Center for Reproductive Medicine and Obstetrics and Gynecology the Affiliated Drum Tower Hospital of Nanjing University Medical SchoolNanjing 210008China Center for Molecular Reproductive Medicine Nanjing UniversityNanjing 210093China Department of Obstetrics and Gynecology the Affiliated Drum Tower Hospital of Nanjing University Medical SchoolNanjing 210008China NHC Key Lab of Reproduction Regulation Shanghai Institute of Planned Parenthood ResearchPharmacy SchoolFudan UniversityShanghai 200032China Clinical Center for Stem Cell Research the Affiliated Drum Tower Hospital of Nanjing University Medical SchoolNanjing 210008China Orthopedic Hospital Research Center and Broad Stem Cell Center David Geffen School of MedicineUniversity of CaliforniaLos AngelesCAUSA State Key Laboratory of Pharmaceutical Biotechnology Nanjing UniversityNanjing 210008China

Dear Editor,Chemotherapy-induced ovarian failure significantly diminishes ovarian blood flow,ovarian size,and follicular *** plays a vital role in repairing ovarian damage.1 Perivascular stem cells(PSCs),known as mural cells covering the vasculature,are essential for blood vessel formation and postulated as progenitors of mesenchymal stem cells(MSCs).2,3 We previously established umbilical cord artery-derived PSCs(Uca-PSCs)and Wharton’s jelly-derived MSCs(WJ-MSCs)and UcaPSCs display optimal angiogenic capacity in vitro.4 Therefore,we explored the angiogenesis and pro-angiogenesis mechanisms of Uca-PSCs and provided them as an efficient treatment strategy for ovarian failure.

关键词： CD146 treatment artery damage

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