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Historical growth of concept networks in Wikipedia

Collective Intelligence 2022年第2期1卷 26339137221109839页

作者： Harang Ju Dale Zhou Ann S Blevins David M Lydon-Staley Judith Kaplan Julio R Tuma Dani S Bassett Neuroscience Graduate Group University of Pennsylvania Philadelphia PA USA Department of Bioengineering School of Engineering & Applied Science University of Pennsylvania Philadelphia PA USA Annenberg School for Communication University of Pennsylvania Philadelphia PA USA Department of History and Sociology of Science College of Arts and Sciences University of Pennsylvania Philadelphia PA USA Integrated Studies Program College of Arts and Sciences University of Pennsylvania Philadelphia PA USA Integrated Studies Program College of Arts and Sciences University of Pennsylvania Philadelphia PA USA Department of Philosophy College of Arts and Sciences University of Pennsylvania Philadelphia PA USA Department of Electrical & Systems Engineering School of Engineering & Applied Science University of Pennsylvania Philadelphia PA USA Department of Physics & Astronomy College of Arts & Sciences University of Pennsylvania Philadelphia PA USA Department of Neurology Perelman School of Medicine University of Pennsylvania Philadelphia PA USA Department of Psychiatry Perelman School of Medicine University of Pennsylvania Philadelphia PA USA Santa Fe Institute Santa Fe NM USA

Philosophers of science have long questioned how collective scientific knowledge grows. Although disparate answers have been posited, empirical validation has been challenging due to limitations in collecting and systematizing large historical records. Here, we introduce new methods to analyze scientific knowledge formulated as a growing network of articles on Wikipedia and their hyperlinks. We demonstrate that in Wikipedia, concept networks in subdisciplines of science do not grow by expanding from their central core to reach an ancillary periphery. Instead, science concept networks in Wikipedia grow by creating and filling knowledge gaps. Notably, the process of gap formation and closure may be valued by the scientific community, as evidenced by the fact that it produces discoveries that are more frequently awarded Nobel prizes than other processes. To determine whether and how the gap process is interrupted by paradigm shifts, we operationalize a paradigm as a particular subdivision of scientific concepts into network modules. Hence, paradigm shifts are reconfigurations of those modules. The approach allows us to identify a temporal signature in structural stability across scientific subjects in Wikipedia. In a network formulation of scientific discovery, our findings suggest that data-driven conditions underlying scientific breakthroughs depend as much on exploring uncharted gaps as on exploiting existing disciplines and support policies that encourage new interdisciplinary research.

关键词： science of science networks philosophy of science Wikipedia cavity

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SI-spreading-based network embedding in static and temporal networks

arXiv

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arXiv 2020年

作者： Zhan, Xiu-Xiu Li, Ziyu Masuda, Naoki Holme, Petter Wang, Huijuan Faculty of Electrical Engineering Mathematics and Computer Science Delft University of Technology Mekelweg 4 Delft2628 CD Netherlands Department of Mathematics University at Buffalo State University of New York Buffalo New YorkNY14260-2900 United States Computational and Data-Enabled Science and Engineering Program University at Buffalo State University of New York Buffalo New YorkNY14260-2900 United States Institute of Innovative Research Tokyo Institute of Technology Yokohama226-8503 Japan

Link prediction can be used to extract missing information, identify spurious interactions as well as forecast network evolution. Network embedding is a methodology to assign coordinates to nodes in a low-dimensional vector space. By embedding nodes into vectors, the link prediction problem can be converted into a similarity comparison task. Nodes with similar embedding vectors are more likely to be connected. Classic network embedding algorithms are random-walk-based. They sample trajectory paths via random walks and generate node pairs from the trajectory paths. The node pair set is further used as the input for a Skip-Gram model, a representative language model that embeds nodes (which are regarded as words) into vectors. In the present study, we propose to replace random walk processes by a spreading process, namely the susceptible-infected (SI) model, to sample paths. Specifically, we propose two SI-spreading-based algorithms, SINE and TSINE, to embed static and temporal networks, respectively. The performance of our algorithms is evaluated by the missing link prediction task in comparison with state-of-the-art static and temporal network embedding algorithms. Results show that SINE and TSINE outperform the baselines across all six empirical datasets. We further find that the performance of SINE is mostly better than TSINE, suggesting that temporal information does not necessarily improve the embedding for missing link prediction. Moreover, we study the effect of the sampling size, quantified as the total length of the trajectory paths, on the performance of the embedding algorithms. The better performance of SINE and TSINE requires a smaller sampling size in comparison with the baseline algorithms. Hence, SI-spreading-based embedding tends to be more applicable to large-scale networks. Copyright © 2020, The Authors. All rights reserved.

关键词： Network embeddings

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Multiband EEG signatures decoded using machine learning for predicting rTMS treatment response in MDD

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Journal of Affective Disorders 2025年 388卷 119483页

作者： Arteaga, Alexander Tong, Xiaoyu Zhao, Kanhao Carlisle, Nancy B. Oathes, Desmond J. Fonzo, Gregory A. Keller, Corey J. Zhang, Yu Department of Bioengineering Lehigh University Bethlehem PA United States Department of Psychology Lehigh University Bethlehem PA United States Center for Brain Imaging and Stimulation Department of Psychiatry University of Pennsylvania Perelman School of Medicine Philadelphia PA United States Center for Neuromodulation in Depression and Stress Department of Psychiatry University of Pennsylvania Perelman School of Medicine Philadelphia PA United States Penn Brain Science Translation Innovation and Modulation Center University of Pennsylvania Perelman School of Medicine Philadelphia PA United States Departments of Neurology Neurosurgery Bioengineering and Neuroscience University of Pennsylvania Perelman School of Medicine Philadelphia PA United States Center for Psychedelic Research and Therapy Department of Psychiatry and Behavioral Sciences Dell Medical School The University of Texas at Austin Austin TX United States Department of Psychiatry and Behavioral Sciences Stanford University School of Medicine Stanford CA United States Wu Tsai Neurosciences Institute Stanford University Stanford CA United States Veterans Affairs Palo Alto Healthcare System and the Sierra Pacific Mental Illness Research Education and Clinical Center (MIRECC) Palo Alto CA United States Department of Electrical and Computer Engineering Lehigh University Bethlehem PA United States

Background: Repetitive transcranial magnetic stimulation (rTMS) is a promising treatment for major depression disorder (MDD), particularly for treatment-resistant cases. However, identifying translatable biomarkers predictive of treatment outcomes remains underexplored. Methods: Participants with treatment resistant depression from the TDBRAIN dataset underwent either high frequency rTMS (10 Hz) at the left dorsolateral prefrontal cortex (DLPFC) (Protocol 1, n = 44) or low frequency rTMS (1 Hz) at the right DLPFC (Protocol 2, n = 73). Pre-treatment electroencephalograms (EEG) was collected, and changes in Beck Depression Inventory were measured post-treatment. EEG oscillations were decomposed into multiband intrinsic mode functions (IMF) and integrated under a latent space predictive modeling framework to identify signatures for predicting treatment outcomes. Results: Multiband signatures significantly predicted rTMS outcomes (Protocol 1: r = 0.40, p < 0.01;Protocol 2: r = 0.26, p < 0.05). Key spatial patterns linked to treatment outcomes were identified, revealing three main oscillations: IMF-Alpha, IMF-Beta, and the residual signal. In Protocol 1, critical regions included the left frontal and parietal regions for IMF-Alpha, left frontal-central and right parietal regions for IMF-Beta, and bi-hemispheric central and left parietal-occipital regions for residual signals. In Protocol 2, critical regions involved the left frontal and parietal regions for IMF-Alpha, left frontal-central region IMF-Beta, and right frontal, left frontal-central, midline central, and left parietal-occipital regions for residual signals. These oscillatory features also showed correlations with specific personality measures, suggesting their potential clinical relevance. Conclusion: Our findings demonstrate the promise of machine learning-driven multiband EEG signatures for personalized MDD treatment prediction, offering a translatable pathway for improved patient outcomes. © 2025 Elsevier

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Three-dimensional bioprinting of gelatin methacryloyl (GelMA)

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Bio-Design and Manufacturing 2018年第4期1卷 215-224页

作者： Guoliang Ying Nan Jiang Cunjiang Yu Yu Shrike Zhang Division of Engineering in Medicine Department of MedicineBrigham and Women's HospitalHarvard Medical SchoolCambridgeMA 02139USA School of Materials Science and Engineering Wuhan Institute of TechnologyWuhan 430205People's Republic of China School of Engineering and Applied Sciences Harvard UniversityCambridgeMA 02139USA Departments of Mechanical Engineering Electrical and Computer EngineeringBiomedical EngineeringMaterials Science and Engineering ProgramThe Texas Center for SuperconductivityUniversity of HoustonHoustonTX 77204USA

The three-dimensional (3D)bioprinting technology has progressed tremendously over the past *** controlling the size, shape,and architecture of the bioprinted constructs,3D bioprinting allows for the fabrication of tissue/organ-like constructs with strong structural-functional similarity with their in vivo counterparts at high *** bioink,a blend of biomaterials and living cells possessing both high biocompatibility and printability,is a critical component of *** particular, gelatin methacryloyl (GelMA)has shown its potential as a viable bioink material due to its suitable biocompatibility and readily tunable physicochemical *** GelMA-based bioinks and relevant bioprinting strategies for GelMA bioprinting are briefly reviewed.

关键词： Bioprinting Bioink Gelatin methacryloyl (GelMA) Biofabrication -Tissue engineering Tissue model

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Discovery of ionic impact ionization (I3) in perovskites triggered by a single photon

arXiv

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arXiv 2019年

作者： Xu, Zihan Yu, Yugang Niaz, Iftikhar Ahmad Chen, Yimu Arya, Shaurya Lei, Yusheng Miah, Mohammad Abu Raihan Zhou, Jiayun Zhang, Alex Ce Yan, Lujiang Xu, Sheng Nomura, Kenji Lo, Yu-Hwa Department of NanoEngineering University of California San DiegoCA United States Material Science and Engineering Program University of California San DiegoCA United States Department of Electrical and Computer Engineering University of California San DiegoCA United States

Organic-inorganic metal halide perovskite devices have generated significant interest for LED, photodetector, and solar cell applications due to their attractive optoelectronic properties and substrate-choice flexibility1-4. These devices exhibit slow time-scale response, which have been explained by point defect migration5-6. In this work, we report the discovery of a room temperature intrinsic amplification process in methylammonium lead iodide perovskite (MAPbI3) that can be triggered by few photons, down to a single photon. The electrical properties of the material, by way of photoresponse, are modified by an input energy as small as 0.19 attojoules, the energy of a single photon. These observations cannot be explained by photo-excited electronic band-to-band transitions or prevailing model of photoexcited point defect migration since none of the above can explain the observed macroscopic property change by absorption of single or few photons. The results suggest the existence of an avalanche-like collective motion of iodides and their accumulation near the anode, which we will call "ionic impact ionization" (I3 mechanism). The proposed I3 process is the ionic analog of the electronic impact ionization, and has been considered impossible before because conventionally it takes far more energy to move ions out of their equilibrium position than electrons. We have performed first principle calculations to show that in MAPbI3 the activation energy for the I3 mechanism is appreciably lower than the literature value of the activation energy for the electronic impact ionization. The discovery of I3 process in perovskite material opens up possibilities for new classes of devices for photonic and electronic applications. Copyright © 2019, The Authors. All rights reserved.

关键词： Iodine compounds

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Iterative Motion Compensation reconstruction ultra-short TE(iMoCo UTE) for high resolution free breathing pulmonary MRI

arXiv

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arXiv 2020年

作者： Zhu, Xucheng Chan, Marilynn Lustig, Michael Johnson, Kevin Larson, Peder E.Z. UCSF/UC Berkeley Graduate Program in Bioengineering University of California San Francisco San FranciscoCA United States Department of Radiology and Biomedical Imaging University of California San Francisco San FranciscoCA United States Department of Pediatrics Division of Pediatric Pulmonology University of California San Francisco San FranciscoCA United States Department of Electrical Engineering and Computer Sciences University of California Berkeley BerkeleyCA United States Department of Medical Physics University of Wisconsin Madison MadisonWI United States Department of Radiology University of Wisconsin Madison MadisonWI United States

Purpose: To develop a high scanning efficiency, motion corrected imaging strategy for free-breathing pulmonary MRI by combining a motion compensation reconstruction with a UTE acquisition, called iMoCo UTE. Methods: An optimized golden angle ordering radial UTE sequence was used to continuously acquire data for 5 minutes. All readouts were grouped to different respiratory motion states based on self-navigator signals, then motion resolved data was reconstructed by XD Golden-angle RAdial Sparse Parallel reconstruction (XD-GRASP). One state from the motion resolved images was selected as a reference, and motion fields from the other states to the reference were derived via non-rigid registration. Finally, all motion resolved data and motion fields were reconstructed by using an iterative motion compensation reconstruction with a total generalized variation sparse constraint. Results: The iMoCo UTE strategy was evaluated in volunteers and non-sedated pediatric patient(4-6 y/o) studies. Images reconstructed with iMoCo UTE provided sharper anatomical lung structures, and higher apparent SNR and CNR, compared to using other motion correction strategies, such as soft-gating, motion resolved reconstruction, and non-rigid motion compensation(MoCo). iMoCo UTE also showed promising results in an infant study. Conclusions: The proposed iMoCo UTE combines self-navigation, motion modeling, and a compressed sensing reconstruction to increase scan efficiency, SNR, and reduce respiratory motion in lung MRI. This proposed strategy shows improvements in free breathing lung MRI scans, especially in very challenging application situations, such as pediatric MRI studies. Copyright © 2020, The Authors. All rights reserved.

关键词： Magnetic resonance imaging

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Boosting the Performance of MOEA/D-DRA with a Multi-Objective Hyper-Heuristic Based on Irace and UCB Method for Heuristic Selection

Boosting the Performance of MOEA/D-DRA with a Multi-Objectiv...

引用

Congress on Evolutionary Computation

作者： Lucas Prestes Myriam R. Delgado Ricardo Lüders Richard Gonçalves Carolina P. Almeida Graduate Program in Electrical and Computer Engineering UTFPR Computer Science Department UNICENTRO

Multi-Objective Evolutionary Algorithm based on Decomposition with Dynamical Resource Allocation (MOEA/D-DRA) is one of the most successful decomposition based multiobjective algorithm. Its main feature is a mechanism to allocate different computational effort proportional to the difficult of each subproblem. Despite its success, MOEA/D-DRA has a large set of parameters and operators, whose selection could be a difficult task. This paper aims at improving the performance of MOEA/D-DRA by means of a hyper-heuristic using two parameter/operator selection phases: one off-line strongly based on Iterated Race Automatic Algorithm Configuration (Irace) and another one (online) based on the Upper Confidence Bound (UCB) technique. The proposed approach is compared with the original MOEA/D-DRA, NSGAII and IBEA over 51 instances of 7 well known benchmarks (CEC 2009, GLT, LZ09, MOP, DTLZ, ZDT and WFG). Results show that Irace and UCB are interesting methods to support the hyper-heuristic functioning when selecting parameters/operators of MOEA/D-DRA in the addressed problems.

关键词： Optimization Evolutionary computation Resource management Sociology Statistics Tuning Task analysis

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THz generation by exchange-coupled spintronic emitters

npj Spintronics

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npj Spintronics 2024年第1期2卷 1-8页

作者： Roman Adam Derang Cao Daniel E. Bürgler Sarah Heidtfeld Fangzhou Wang Christian Greb Markus Büscher Claus M. Schneider Jing Cheng Debamitra Chakraborty Ivan Komissarov Roman Sobolewski Martin Mikulics Hilde Hardtdegen Peter Grünberg Institute Research Centre Jülich Jülich Germany College of Physics Qingdao University Qingdao China Faculty of Physics University Duisburg-Essen Duisburg Germany Institut für Laser- und Plasmaphysik Heinrich-Heine Universität Düsseldorf Düsseldorf Germany Materials Science Graduate Program University of Rochester Rochester NY USA Laboratory for Laser Energetics University of Rochester Rochester NY USA Department of Electrical and Computer Engineering University of Rochester Rochester NY USA Ernst Ruska Centre Research Centre Jülich Jülich Germany

The mechanism of THz generation in ferromagnet/metal (F/M) bilayers has been typically ascribed to the inverse spin Hall effect (ISHE). Here, we fabricated Pt/Fe/Cr/Fe/Pt multilayers containing two back-to-back spintronic THz emitters separated by a thin (tCr≤ 3nm) wedge-shaped Cr spacer. In such an arrangement, magnetization alignment of the two Fe films can be controlled by the interplay between Cr-mediated interlayer exchange coupling (IEC) and an external magnetic field. This in turn results in a strong variation of the THz amplitudeA, withA↑↓reaching up to 14 timesA↑↑(arrows indicate the relative alignment of the magnetization of the two magnetic layers). This observed functionality is ascribed to the interference of THz transients generated by two closely spaced THz emitters. Moreover, the magnetic field dependenceA(H) shows a strong asymmetry that points to an additional performance modulation of the THz emitter via IEC and multilayer design.

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Magnetless Circulators with Harmonic Rejection Based on N-Way Cyclic-Symmetric Time-Varying Networks

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Physical Review Applied 2019年第2期12卷 024046-024046页

作者： Ahmed Kord Harish Krishnaswamy Andrea Alù Department of Electrical and Computer Engineering The University of Texas at Austin Austin Texas 78712 USA Department of Electrical Engineering Columbia University New York New York 10027 USA Photonics Initiative Advanced Science Research Center City University of New York New York New York 10031 USA Physics Program Graduate Center City University of New York New York New York 10026 USA Department of Electrical Engineering City College of New York New York New York 10031 USA

Magnetfree circulators are crucial devices to enable full-duplex communications with the goal of enhancing the spectral efficiency of wireless radios compared to currently deployed half-duplex systems. Nevertheless, implementations proposed to date at radio- and millimeter-wave frequencies have been based on spatiotemporally modulating a discrete number of nonlinear elements, such as varactors or switched capacitors, which, despite achieving strong nonreciprocity, suffer from spurious emission in adjacent channels and limited power handling. These problems jeopardize the practical use of these components in many applications, including wireless communications and quantum computing, and make them less attractive compared to harmonicfree magnetic devices. We address these problems by introducing N-way circulators, which consist of N spatiotemporally modulated angular-momentum (STM AM) biased units connected either in series or in parallel and modulated through a rotating phase pattern. We show that these circuits, for a sufficiently large N, effectively impart an overall linear and continuous angular-momentum bias, which significantly reduces spurious emission and increases the overall power handling. This, in turn, strengthens the argument of magnetless circulators compared to their magnetic counterparts, and opens exciting venues to address the realistic needs of practical systems.

关键词： Electromagnetism Metamaterials Photonics Quantum information with hybrid systems Devices T-symmetry

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High-resolution label-free imaging of tissue morphology with confocal phase microscopy

arXiv

引用

arXiv 2020年

作者： Schnell, Martin Gupta, Shravan Wrobel, Tomasz P. Drage, Michael G. Bhargava, Rohit Carney, P. Scott Beckman Institute for Advanced Science and Technology University of Illinois at Urbana-Champaign UrbanaIL61801 United States Institute of Optics University of Rochester 480 Intercampus Drive RochesterNY14620 United States Solaris National Synchrotron Radiation Centre Jagiellonian University Czerwone Maki 98 Krakow30-392 Poland Department of Pathology and Laboratory Medicine University of Rochester Medical Center RochesterNY14642 United States Department of Bioengineering Department of Chemical and Biomolecular Engineering Cancer Center at Illinois Department of Electrical and Computer Engineering Department of Chemistry University of Illinois at Urbana-Champaign UrbanaIL61801 United States

Label-free imaging approaches seek to simplify and augment histopathologic assessment by replacing the current practice of staining by dyes to visualize tissue morphology with quantitative optical measurements. Quantitative phase imaging (QPI) operates with visible/UV light and thus provides a resolution matched to current practice. Here we introduce and demonstrate confocal QPI for label-free imaging of tissue sections and assess its utility for manual histopathologic inspection. Imaging cancerous and normal adjacent human breast and prostate, we show that tissue structural organization can be resolved with high spatial detail comparable to conventional H&E stains. Our confocal QPI images are found to be free of halo, solving this common problem in QPI. We further describe and apply a virtual imaging system based on Finite-Difference Time-Domain (FDTD) calculations to quantitatively compare confocal with wide-field QPI methods and explore performance limits using numerical tissue phantoms. Copyright © 2020, The Authors. All rights reserved.

关键词： Optical data processing

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