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journal of Computational Mathematics 2024年第2期42卷 570-596页

作者： Shi Chen Zhiyan Ding Qin Li stephen j.Wright Mathematics Department University of Wisconsin-MadisonMadisonWI 53706USA Department of Mathematics University of California-BerkeleyBerkeley CA 94720USA Mathematics Department and Discovery Institute University of Wisconsin-Madison MadisonWI 53706USA Computer Sciences Department University of WisconsinMadisonWI 53706USA

Neural networks are powerful tools for approximating high dimensional data that have been used in many contexts,including solution of partial differential equations(PDEs).We describe a solver for multiscale fully nonlinear elliptic equations that makes use of domain decomposition,an accelerated Schwarz framework,and two-layer neural networks to approximate the boundary-to-boundarymap for the subdomains,which is the key step in the Schwarz ***,the boundary-to-boundary map requires solution of boundary-value elliptic problems on each *** leveraging the compressibility of multiscale problems,our approach trains the neural network offline to serve as a surrogate for the usual implementation of the boundary-to-boundary *** method is applied to a multiscale semilinear elliptic equation and a multiscale p-Laplace *** both cases we demonstrate significant improvement in efficiency as well as good accuracy and generalization performance.

关键词： Nonlinear homogenization Multiscale elliptic problem Neural networks Do-main decomposition

DEM investigation of strength and critical state behaviours of granular materials under true triaxial loadings

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Particuology 2024年第2期85卷 198-212页

作者： Minyi Zhu Guobin Gong jun Xia stephen Wilkinson Department of Civil Engineering Xi'an Jiaotong-Liverpool UniversityChina Department of Civil Engineering and Industrial Design University of LiverpoolLiverpoolUK Faculty of Engineering and Information Sciences University of Wollongong in DubaiUnited Arab Emirates

This paper investigates the strength and critical state(CS)behaviours of granular materials via DEM simulations of true triaxial drained tests under three different loading modes including constant b(in-termediate stress ratio)tests with constantσ'1(major principal stress),constant p(mean pressure)and constantσ'3(minor principal stress)*** this end,a series of samples are generated with the same particle size distribution,and with the confining stresses ranging from 100 kPa to 900 *** CS is achieved for all *** the macroscopic behaviours and the microscopic behaviours are examined and compared considering different loading modes,confining stresses and intermediate stress ratios(b).The critical state lines(CSLs)are found to be unique and independent of the loading modes,but dependent on the b *** CSLs with b=0 and b=1 form the two boundaries of CSLs respectively beyond which CSLs under all other b tests cannot go *** different strength criteria are examined and compared in terms of both peak and CS *** Mohr-Coulomb strength criterion is found to be only suitable for axisymmetric loading *** Lade-Duncan criterion is only suitable for describing peak strengths,which is dependent on the loading modes and confining *** Satake criterion and Matsuoka-Nakai criterion are the more appropriate strength criteria for describing CS failures,indicating that the CS values of both the Satake parameter and the Matsuoka-Nakai parameter describe an inherent property that characterizes the CS failure for a given type of *** CS mechanical coordination number is fitted by a curved line for a given b value,which is unique regardless of the loading *** peak and CS values of both major and minor principal fabric tensors decrease with increasing b values,while they increase with increasing b values for the intermediate principal fabric tensor.

关键词： Discrete element method Intermediate stress ratio Dilation Critical state Failure criterion

The replication crisis and its relevance to Earth Science studies:Case studies and recommendations

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Geoscience Frontiers 2024年第4期15卷 304-314页

作者： stephen j.Puetz Kent C.Condie Kurt Sundell Nick M.W.Roberts Christopher j.Spencer Slah Boulila Qiuming Cheng 475 Atkinson Dr Suite 704HonoluluHI 96814USA New Mexico Institute of Mining and Technology SocorroNM 87801USA Idaho State University PocatelloID 83209USA Geochronology and Tracers Facility British Geological SurveyKeyworthNottingham NG125GGUK Queen’s University Department of Geological Sciences and Geological EngineeringKingstonOntario K7L 3N6Canada Sorbonne Université CNRSInstitut des Sciences de la Terre ParisParisFrance State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China

Numerous scientific fields are facing a replication crisis,where the results of a study often cannot be replicated when a new study uses independent *** issue has been particularly emphasized in psychology,health,and medicine,as incorrect results in these fields could have serious consequences,where lives might be at *** other fields have also highlighted significant replication problems,the Earth Sciences seem to be an *** paucity of Earth Science research aimed at understanding the replication crisis prompted this ***,this work aims to fill that gap by seeking to replicate geological results involving various types of *** identify and discuss 11 key variables for replicating U-Pb age distributions:independent data,global sampling,proxy data,data quality,disproportionate non-random sampling,stratigraphic bias,potential filtering bias,accuracy and precision,correlating time-series segments,testing assumptions and divergent analytical methods,and analytical *** while this work primarily focuses on U-Pb age distributions,most of these factors(or variations of them)also apply to other geoscience ***,some of the discussions involve time-series consisting ofεHf,δ18O-zircon,14C,10Be,marineδ13C,and marineδ*** then provide specific recommendations for minimizing adverse effects related to these factors,and in the process enhancing prospects for replicating geological results.

关键词： Replication crisis Replicability Independent data Global time-series Globality index Filtered data

Regional trends and petrologic factors inhibit global interpretations of zircon trace element compositions

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Geoscience Frontiers 2024年第5期15卷 300-307页

作者： Nick M.W.Roberts Christopher j.Spencer stephen Puetz C.Brenhin Keller Simon Tapster Geochronology and Tracers Facility British Geological SurveyNottingham NG125GGUK Department of Geological Sciences and Geological Engineering Queen’s UniversityKingstonOntarioCanada Atkinson Dr Suite 704HonoluluHI 96814USA Department of Earth Sciences Dartmouth CollegeHanoverNew HamphireUSA

The trace element composition of zircon reveals information about the melt that they are derived from,as such,detrital zircon trace element compositions can be used to interrogate melt compositions,and thus the evolution of the continental crust in time and ***,we present a global database of detrital zircon compositions and use it to test whether average global trends for five common petrogenetic proxies truly represent secular changes in continental *** demonstrate that the secular trend is broadly comparable across continental regions for Ti-in-zircon temperatures,but for other trace element ratios interrogated,secular trends are highly variable between continental *** trace element ratios result from multiple petrologic variables,we argue that these petrogenetic proxies can be overinterpreted if projected to global geologic *** particular,we caution against the interpretation of crustal thickness from trace elements in zircon,and we argue that our results negate current hypotheses concerning secular changes in crustal thickness.

关键词： Detrital zircon Trace elements Secular change Eu anomaly Crustal thickness

Non-canonical BRAF variants and rearrangements in hairy cell leukemia

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Oncology Research 2024年第9期32卷 1423-1427页

作者： stephen E.LANGABEER Cancer Molecular Diagnostics St.James’s HospitalDublinD08 W9RTIreland

Hairy cell leukemia(HCL)is an uncommon mature B-cell malignancy characterized by a typical morphology,immunophenotype,and clinical *** vast majority of HCL patients harbor the canonical BRAF V600E mutation which has become a rationalized target of the subsequently deregulated RAS-RAF-MEK-MAPK signaling pathway in HCL patients who have relapsed or who are refractory to front-line ***,several HCL patients with a classical phenotype display non-canonical BRAF mutations or *** include sequence variants within alternative exons and an oncogenic fusion with the IGH *** must be taken in the molecular diagnostic work-up of patients with typical HCL but without the BRAF V600E to include investigation of these uncommon ***,functional characterization,and reporting of further such patients is likely to provide insights into the pathogenesis of HCL and enable rational selection of targeted inhibitors in such patients if required.

关键词： Hairy cell leukemia BRAF Molecular diagnostics Targeted therapy

DCFNet:Discriminant Correlation Filters Network for Visual Tracking

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journal of Computer Science & Technology 2024年第3期39卷 691-714页

作者：胡卫明王强高晋李兵 stephen Maybank State Key Laboratory of Multimodal Artificial Intelligence Systems Institute of AutomationChinese Academy of Sciences Beijing 100190China Department of Computer Science and Information Systems Birkbeck CollegeLondon WC1E 7HXU.K.

CNN(convolutional neural network)based real time trackers usually do not carry out online network update in order to maintain rapid tracking *** inevitably influences the adaptability to changes in object *** filter based trackers can update the model parameters online in real *** this paper,we present an end-to-end lightweight network architecture,namely Discriminant Correlation Filter Network(DCFNet).A differentiable DCF(discriminant correlation filter)layer is incorporated into a Siamese network architecture in order to learn the convolutional features and the correlation filter *** correlation filter can be efficiently updated *** previous work,we introduced a joint scale-position space to the DCFNet,forming a scale DCFNet which carries out the predictions of object scale and position *** combine the scale DCFNet with the convolutional-deconvolutional network,learning both the high-level embedding space representations and the low-level fine-grained representations for *** adaptability of the fine-grained correlation analysis and the generalization capability of the semantic embedding are complementary for visual *** back-propagation is derived in the Fourier frequency domain throughout the entire work,preserving the efficiency of the *** evaluations on the OTB(Object Tracking Benchmark)and VOT(Visual Object Tracking Challenge)datasets demonstrate that the proposed trackers have fast speeds,while maintaining tracking accuracy.

关键词： correlation filter convolutional neural network(CNN) visual tracking

Role of intravascular ultrasound and optical coherence tomography in intracoronary imaging for coronary artery disease:a systematic review

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journal of Geriatric Cardiology 2024年第1期21卷 104-129页

作者： Maruf Sarwar stephen Adedokun Mahesh Anantha Narayanan Department of Cardiovascular Sciences White River HealthBatesvilleARUSA Division of Cardiology University of Tennessee at MemphisTNUSA University of Arkansas Medical Sciences Little RockARUSA

Coronary angiography has long been the standard for coronary imaging,but it has limitations in assessing vessel wall anatomy and guiding percutaneous coronary intervention(PCI).Intracoronary imaging techniques like intravascular ultrasound(IVUS)and optical coherence tomography(OCT)can overcome these *** uses ultrasound and OCT uses near-infrared light to visualize coronary pathology in unique ways due to differences in temporal and spatial *** techniques have evolved to offer clinical utility in plaque characterization and vessel assessment during ***-analyses and adjusted observational studies suggest that both IVUS and OCT-guided PCI correlate with reduced cardiovascular risks compared to angiographic guidance *** IVUS demonstrates consistent clinical outcome benefits,OCT evidence is less *** has progressed from early motion detection to high-resolution systems,with smaller compatible *** utilizes near infrared light to achieve unparalleled resolutions,but requires temporary blood clearance for optimal *** visualization and guidance make IVUS and OCT well-suited for higher risk PCI in patients with diabetes and chronic kidney disease by allowing detailed visualization of complex lesions and ensuring optimal stent deployment and positioning in PCI for patients with type 2 diabetes and chronic kidney disease,improving *** and recent advancements in zero-and low-contrast OCT techniques can reduce nephrotoxic contrast exposure,thus helping to minimize PCI complications in these high-risk patient *** and OCT provide valuable insights into coronary pathophysiology and guide interventions precisely compared to angiography *** have comparable clinical outcomes,emphasizing the need for tailored imaging choices based on clinical *** refinement and integration of intravascular imaging will likely play a pivotal role in optimizing coronary interventions and outcomes.

关键词： coronary anatomy limitations

The effects of local variations in conditions on carbon storage and release in the continental mantle

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National Science Review 2024年第6期11卷 22-36页

作者： stephen F.Foley Chunfei Chen Dorrit E.jacob School of Natural Sciences Macquarie University Research School of Earth Sciences Australian National University State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences China University of Geosciences

Recent advances indicate that the amount of carbon released by gradual degassing from the mantle needs to be revised upwards, whereas the carbon supplied by plumes may have been overestimated in the *** in rock types and oxidation state may be very local and exert strong influences on carbon storage and release mechanisms. Deep subduction may be prevented by diapirism in thick sedimentary packages,whereas carbonates in thinner sequences may be subducted. Carbonates stored in the mantle transition zone will melt when they heat up, recognized by coupled stable isotope systems(e.g. Mg, Zn, Ca). There is no single ‘mantle oxygen fugacity’, particularly in the thermal boundary layer(TBL) and lowermost lithosphere, where very local mixtures of rock types coexist. Carbonate-rich melts from either subduction or melting of the uppermost asthenosphere trap carbon by redox freezing or as carbonate-rich dykes in this zone. Deeply derived, reduced melts may form further diamond reservoirs, recognized as polycrystalline diamonds associated with websteritic silicate minerals. Carbon is released by either edge-driven convection,which tears sections of the TBL and lower lithosphere down so that they melt by a mixture of heating and oxidation, or by lateral advection of solids beneath rifts. Both mechanisms operate at steps in lithosphere thickness and result in carbonate-rich melts, explaining the spatial association of craton edges and carbonate-rich magmatism. High-pressure experiments on individual rock types, and increasingly on reactions between rocks and melts, are fine-tuning our understanding of processes and turning up unexpected results that are not seen in studies of single rocks. Future research should concentrate on elucidating local variations and integrating these with the interpretation of geophysical signals. Global concepts such as average sediment compositions and a uniform mantle oxidation state are not appropriate for small-scale processes; an increa

关键词： lithospheric mantle carbonate melts deep carbon cycle craton destruction continental rifts

Rapid growth in a large Cambrian apex predator

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National Science Review 2024年第3期11卷 128-136页

作者：吴雨 stephen Pates Daniel Pauly 张兴亮傅东静 State Key Laboratory of Continental Dynamics and Shaanxi Key Laboratory of Early Life and Environment Department of Geology Northwest University Department of Zoology University of Cambridge Institute for the Oceans and Fisheries University of British Columbia Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences

Despite the importance of ontogenetic data on early diverging euarthropods to our understanding of the ecology and evolution of past life, the data are distinctly lacking, as reconstructing life histories of fossil animals is often challenging. Here we report the growth trajectory of frontal appendages of the apex predator Amplectobelua symbrachiata, one of the most common radiodont arthropods from the early Cambrian Chengjiang biota(c. 520 Ma) of China. Analysis of 432 specimens(9.1–137.1 mm length; 1.3–25.6 mm height) reveals that appendages grew isometrically, with an estimated maximum size of the whole animal of c. 90 cm. Individuals grew rapidly compared to extant arthropods, as assessed using the electronic length-frequency analysis(ELEFAN) approach. Therefore, we show that the Cambrian apex predator A. symbrachiata was an extremely fast-growing arthropod, with an unusual life history strategy that formed as part of the escalatory ‘arms race’ that shaped the Cambrian explosion over 500 Ma.

关键词： stem-group Euarthropoda Radiodonta post-embryonic development growth dynamics Cambrian Explosion