You are currently viewing a new version of our website. To view the old version click .

Advancing Open Science

The world's leading open access publisher. Supporting research communities and accelerating scientific discovery since 1996.

  • 6.4 billionArticle Views
  • 4.4 millionTotal Authors
  • 97%Web of Science Coverage

News & Announcements

Journals

  • Comparative Analysis of the Accuracy and Robustness of the Leap Motion Controller 2

    • Daniel Matuszczyk,
    • Mikel Jedrusiak and
    • Denis Fisseler
    • + 1 author

    Along with the ongoing success of virtual/augmented reality (VR/AR) and human–machine interaction (HMI) in the professional and consumer markets, new compatible and inexpensive hand tracking devices are required. One of the contenders in this market is the Leap Motion Controller 2 (LMC2), successor to the popular Leap Motion Controller (LMC1), which has been widely used for scientific hand-tracking applications since its introduction in 2013. To quantify ten years of advances, this study compares both controllers using quantitative tracking metrics and characterizes the interaction space above the sensor. A robot-actuated 3D-printed hand and a motion-capture system provide controlled movements and external reference data. In the central tracking volume, the LMC2 achieves improved performance, reducing palm-position error from 7.9–9.8 mm (LMC1) to 5.2–5.3 mm (LMC2) and lowering positional variability from 1.3–2.2 mm to 0.4–0.8 mm. Dynamic tests confirm stable tracking for both devices. For boundary experiments, the LMC2 maintains continuous detection at distances up to 666 mm, compared to 250–275 mm (LMC1), and detects hands entering the field of view from distances up to 646 mm. Both devices show reduced accuracy toward the edges of the tracking volume. Overall, the results provide a grounded characterization of LMC2 performance in its newly emphasized VR/AR-relevant interaction spaces, while the metrics support cross-comparison with earlier LMC1-based studies and transfer to related application scenarios.

    Sensors,

    8 December 2025

  • Monitoring landslide displacement and anti-slide pile damage is critical for assessing the stability of progressive loess landslides. To address the challenge of capturing precursor information for loess landslide instability under anti-slide pile reinforcement, this study systematically investigates the damage evolution process of slides (through their “slide-stability-reslide” cycles) and anti-slide piles under acoustic emission (AE) monitoring. Cyclic loading tests were employed to simulate the movement of progressive loess landslides. Based on the core causal logic that “slide displacement induces pile damage, damage generates AE signals, and signals invert displacement status”, a laboratory-scale physical model was designed to simultaneously monitor slide displacement, pile stress, and AE signals. The research results indicate that the dominant frequency and amplitude of AE signals are significantly correlated with slide displacement: with cyclic loading, both the dominant frequency and amplitude exhibit a “low → high → low” characteristic, corresponding to “low/medium-frequency low-amplitude”, “medium/high-frequency medium-high-amplitude” and “low-frequency medium-high-amplitude” signals in the three stages of slide deformation, respectively. The Kaiser and Felicity effects effectively monitor pile damage, and the decrease in Felicity ratio serves as a precursor for landslide early warning. Research results can provide a new methodological framework for early warning systems in pile-reinforced loess landslides.

    Sensors,

    8 December 2025

  • Rice husks, wastes from rice production, are expected to be useful as a phosphorus recovery material. While rice husks could be used for phosphorus recovery as they are, there is potential to increase their phosphorus recovery capacity by diopside conversion. This is because diopside is one of the silica-based biomaterials that has the characteristic of precipitating calcium phosphate from aqueous solutions containing phosphorus, such as body fluids. In this study, diopside was synthesized by immersing Aichi no Kaori rice husks in a Ca–Mg aqueous solution followed by calcination. The diopside content of resulting compound was 12%. Phosphorus recovery by the diopside-containing compound was confirmed. Given the diopside content in the compound, it was considered possible that components other than diopside might also be contributing to the phosphorous recovery.

    Bioengineering,

    8 December 2025

  • Coaxial closed-loop geothermal systems, increasingly recognized as scalable and low-impact geothermal solutions, remain limited by conductive heat transfer between the reservoir and wellbore. This study investigates three strategies to enhance thermal output: (i) dynamic operation scheduling, (ii) substitution of conventional fluids with Organic Rankine Cycle (ORC) working fluids, and (iii) targeted conductive enhancements near the well. Using a CMG STARS simulation framework, system performance was evaluated over 1- to 20-year horizons, introducing a characteristic thermal recovery curve as a tool for analyzing long-term behavior. Results show that extended recovery durations raise outlet temperatures but with diminishing returns, identifying approximately 80% recovery as a practical optimization point. Fluids such as n-pentane and R245fa deliver substantially greater ORC-compatible heat than water, with thermo-siphoning observed under low-flow conditions. Conductive enhancement geometries, namely ring and fishbone configurations, exhibit distinct performance profiles, with rings outperforming fishbones due to larger injected volumes and greater advantage due to reservoir reach. One-year gains range from 4.5–9.4% for rings and 0.65–1.37% for fishbones, stabilizing at 3.7–7.8% and 0.55–1.18% after 20 years. These findings provide design and operational guidance for advancing coaxial closed-loop systems in low-carbon energy deployment.

    Processes,

    8 December 2025

  • Showrooming behavior on the part of consumers undoubtedly undermines the interests of brick-and-mortar (BM) retailers and hinders the growth of the physical economy. In response to this crisis, BM retailers can employ exclusive product strategies, although the questions of which specific strategy is most beneficial and what factors influence retailers’ choices remain unanswered. Based on utility theory and optimization theory, this paper investigates two strategies: the store exclusive brand (SEB) strategy and the well-known exclusive brand (WEB) strategy. First, we identify the pricing methods for both strategies employed by BM retailers, thereby revealing that the pricing of exclusive products under the SEB strategy should be higher than the corresponding pricing under the WEB strategy, whereas the pricing of nonexclusive products should be the opposite. Moreover, service levels should remain consistent under both strategies. Second, both strategies benefit retailers primarily by increasing their market share; interestingly, this process leads to the same overall growth in market share for BM retailers. Third, our analysis reveals that exclusive strategies always yield higher profits than nonexclusive strategies do. We also address the optimal choice between the SEB strategy and the WEB strategy for BM retailers. This choice depends on the relationship between the probability that a consumer can evaluate and purchase the best-fit product correctly online and the proportion of low-type consumers. If the former probability is low while the latter proportion is high, the SEB strategy is the best strategy. Otherwise, the WEB strategy is superior. Finally, numerical examples are provided to facilitate discussion of the effects of critical parameters on the outcomes of both strategies. Overall, this study explores the application of exclusive product strategies by BM retailers seeking to mitigate the negative effects of showrooming on service-oriented products; this research also emphasizes the crucial factors involved in the process of implementing these two strategies.

    Mathematics,

    8 December 2025

  • Exploring Stability and Chaos in the Fractional-Order Arneodo System via Grünwald–Letnikov Scheme

    • Mohamed Elbadri,
    • Manahil A. M. Ashmaig and
    • Abdelgabar Adam Hassan
    • + 4 authors

    This paper investigates the dynamical properties of the fractional-order Arneodo system using a Grünwald–Letnikov-based numerical discretization. Fractional-order operators introduce memory and hereditary effects, enabling a more realistic description than classical integer-order models. The local stability of equilibrium points is examined through eigenvalue analysis of the Jacobian matrix, along with dissipativity conditions and the emergence of complex attractors. A comprehensive dynamical investigation is presented through phase portraits, time series, Lyapunov exponents, and bifurcation diagrams for varying fractional orders. Numerical findings demonstrate the emergence of new chaotic and hyperchaotic attractors. The results confirm that the fractional order strongly influences the system’s stability, sensitivity, and complexity. Our results confirm the relevance of fractional-order modeling in applications, such as secure communication, random number generation, and complex system analysis.

    Mathematics,

    8 December 2025

    • Feature Paper
    • Article
    • Open Access

    Mirror Descent and Exponentiated Gradient Algorithms Using Trace-Form Entropies

    • Andrzej Cichocki,
    • Toshihisa Tanaka and
    • Frank Nielsen
    • + 1 author

    This paper introduces a broad class of Mirror Descent (MD) and Generalized Exponentiated Gradient (GEG) algorithms derived from trace-form entropies defined via deformed logarithms. Leveraging these generalized entropies yields MD and GEG algorithms with improved convergence behavior, robustness against vanishing and exploding gradients, and inherent adaptability to non-Euclidean geometries through mirror maps. We establish deep connections between these methods and Amari’s natural gradient, revealing a unified geometric foundation for additive, multiplicative, and natural gradient updates. Focusing on the Tsallis, Kaniadakis, Sharma–Taneja–Mittal, and Kaniadakis–Lissia–Scarfone entropy families, we show that each entropy induces a distinct Riemannian metric on the parameter space, leading to GEG algorithms that preserve the natural statistical geometry. The tunable parameters of deformed logarithms enable adaptive geometric selection, providing enhanced robustness and convergence over classical Euclidean optimization. Overall, our framework unifies key first-order MD optimization methods under a single information-geometric perspective based on generalized Bregman divergences, where the choice of entropy determines the underlying metric and dual geometric structure.

    Entropy,

    8 December 2025

  • Introduction: Autoimmune encephalitis (AE) is a neurological disorder caused by immune responses targeting neuron-surface or synaptic proteins. While its immunological mechanisms have been studied, the genetic underpinnings remain unclear. This study investigates whether rare deleterious variants (RDVs) in immunological genes contribute to AE susceptibility. Method: We enrolled 36 patients with AE and 407 healthy controls without autoimmune diseases. Whole-exome sequencing was performed to identify RDVs, including start-loss, stop-gain, frameshift, splice-site variants, and deleterious missense mutations. We analyzed the distribution of RDVs in an immunological gene set and its subsets. A burden test was used to identify genes significantly associated with AE. Results: Overall, RDVs in the full immunological gene set did not differ between AE patients and controls. However, the T cell receptor signaling pathway subset showed a significantly higher RDV burden in AE patients. Within this pathway, PDK1 was significantly associated with AE. Two additional genes, CAT and MIA, also showed strong associations, although their broader gene subset, cytokines, did not display differential RDV distribution. Discussion: Our findings suggest that RDVs in specific immunological pathways, particularly the T cell receptor signaling pathway, may play a role in AE pathogenesis. The significant associations of PDK1, CAT, and MIA with AE highlight potential genetic contributors to the disease. Further functional studies are necessary to validate these associations and explore their biological relevance, potentially paving the way for improved understanding and future therapeutic targets in AE.

    Neurol. Int.,

    8 December 2025

Partnerships