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  1. Abstract

    Massive historical newspaper collections contain rich information about the historical development of social issues and constitute a unique resource for studying the social construction of issues such as juvenile delinquency. However, manual analysis of millions of pages of newspaper articles is infeasible. In this paper, we propose a suite of computational methods, including cross-context lexical analysis, dynamic semantic analysis, and valence analysis, to facilitate the study of historical social construction. We apply these methods to ProQuest Historical Newspapers$$^{\textrm{TM}}$$TMcollection in the period of 1790–2006 to study the social construction of juvenile delinquency over this period. Our results show that the proposed methods are effective in revealing insights regarding the social construction of juvenile delinquency, leading to a better understanding of this complex issue and specific hypotheses for further study. Overall, our study shows the great promise of leveraging natural language processing techniques for analyzing historical news data to study social construction of societal issues.

     
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  2. Free, publicly-accessible full text available May 29, 2025
  3. Free, publicly-accessible full text available May 1, 2025
  4. Abstract

    Chiral orbital currents (COC) underpin a novel colossal magnetoresistance in ferrimagnetic Mn3Si2Te6. Here we report the Hall effect in the COC state which exhibits the following unprecedented features: (1) A sharp, current-sensitive peak in the magnetic field dependence of the Hall resistivity, and (2) A current-sensitive scaling relation between the Hall conductivityσxyand the longitudinal conductivityσxx, namely,σxyσxxαwith α reaching up to 5, which is exceptionally large compared toα ≤ 2 typical of all solids. The novel Hall responses along with a current-sensitive carrier density and a large Hall angle of 15% point to a giant, current-sensitive Hall effect that is unique to the COC state. Here, we show that a magnetic field induced by the fully developed COC combines with the applied magnetic field to exert the greatly enhanced transverse force on charge carriers, which dictates the COC Hall responses.

     
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  5. Free, publicly-accessible full text available January 1, 2025
  6. Free, publicly-accessible full text available December 14, 2024
  7. In this paper, we introduce Max Markov Chain (MMC), a novel model for sequential data with sparse correlations among the state variables.It may also be viewed as a special class of approximate models for High-order Markov Chains (HMCs).MMC is desirable for domains where the sparse correlations are long-term and vary in their temporal stretches.Although generally intractable, parameter optimization for MMC can be solved analytically.However, based on this result,we derive an approximate solution that is highly efficient empirically.When compared with HMC and approximate HMC models, MMCcombines better sample efficiency, model parsimony, and an outstanding computational advantage.Such a quality allows MMC to scale to large domainswhere the competing models would struggle to perform.We compare MMC with several baselines with synthetic and real-world datasets to demonstrate MMC as a valuable alternative for stochastic modeling.

     
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  8. Free, publicly-accessible full text available December 1, 2024
  9. Volumetric printing, an emerging additive manufacturing technique, builds objects with enhanced printing speed and surface quality by forgoing the stepwise ink-renewal step. Existing volumetric printing techniques almost exclusively rely on light energy to trigger photopolymerization in transparent inks, limiting material choices and build sizes. We report a self-enhancing sonicated ink (or sono-ink) design and corresponding focused-ultrasound writing technique for deep-penetration acoustic volumetric printing (DAVP). We used experiments and acoustic modeling to study the frequency and scanning rate–dependent acoustic printing behaviors. DAVP achieves the key features of low acoustic streaming, rapid sonothermal polymerization, and large printing depth, enabling the printing of volumetric hydrogels and nanocomposites with various shapes regardless of their optical properties. DAVP also allows printing at centimeter depths through biological tissues, paving the way toward minimally invasive medicine.

     
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    Free, publicly-accessible full text available December 8, 2024