内布拉斯加大学系统

Understanding balance control mechanisms is essential for designing effective assessment and rehabilitation strategies. Wobble-board tasks that introduce continuous postural instability offer a valuable method to investigate and enhance proactive and emergent balance control mechanisms. This study aimed to investigate proactive and emergent balance control strategies using a mediolaterally unstable wobble board, focusing on several spatial and temporal characteristics of balance control in healthy young adults. Twenty-nine healthy young adults performed wobble-board tasks under two conditions: with and without a concurrent cognitive load (Trail Making Task). The study examined two primary outcome measures: (i) spatial—peak excursion magnitude of the board and (ii) temporal—cycle duration of the board’s movement. The Hurst exponent was used to characterize the stochastic properties of each series. In addition, Principal Component Analysis (PCA) and Canonical Correlation Analysis (CCA) were employed to assess the relationship between wobble-board dynamics and traditional balance metrics (center-of-pressure, CoP, center-of-mass, CoM, and CoP–CoM). Temporal control, indexed by cycle duration, exhibited a Hurst exponent near H=0.48 , consistent with uncorrelated, emergent adjustments (Brownian-like), whereas spatial control, indexed by excursion magnitude, showed H=0.73 , indicating persistent, proactive regulation likely mediated by proprioceptive/reflexive feedback. These signatures were preserved under cognitive load, suggesting robust spatial control alongside load-resilient, self-organizing temporal dynamics. PCA and CCA further showed that the WB metrics capture information complementary to CoP and CoP–CoM, with high cross-set correlations underscoring their multidimensional value. Finally, cyclical WB metrics (e.g., RMS peak angular excursion, cycle frequency) demonstrated moderate-to-high test–retest reliability (ICCs =0.77–0.86 ), whereas fractal-like measures (Hurst exponents) showed lower consistency (ICCs =0.19–0.45 ), indicating greater sensitivity to trial-to-trial fluctuations. Wobble-board assessment isolates a dual-mode balance strategy in which spatial regulation is actively controlled while temporal structure self-organizes. The separation yields actionable targets for metric-guided, progressive training that emphasizes excursion control while monitoring temporal adaptability. Because these metrics complement conventional CoP/CoM measures, they offer a practical bridge from laboratory to clinic-friendly evaluation and feedback. Validation in aging and clinical cohorts and outcomes-focused longitudinal trials will determine their translational value for fall prevention and rehabilitation.

This study investigates the interplay of internal and external factors in eco-innovation by analyzing survey data from 345 firms. This research aims to examine firm performance by employing the theoretical frameworks of resource-based theory and contingency theory. It establishes a model exploring the relationship between eco-innovation capabilities, firm performance, and the moderating influence of partnerships with alliances and partnership with universities. Findings reveal positive effects of eco-innovation capabilities on firm performance. Additionally, partnership with alliances and partnership with universities both have a significant positive moderating effect on the relationship between eco-innovation capabilities and firm performance. The study offers managerial insights and policy recommendations based on empirical results, emphasizing the importance of fostering eco-innovation capabilities and strategic partnerships for enhanced firm performance.

Multifractality is a hallmark of healthy physiological dynamics, reflecting structured variability across timescales and fluctuation intensities. Yet the generative mechanisms that sustain robust multifractal scaling - particularly across both weak and strong fluctuations - remain poorly understood, limiting our ability to build physiologically plausible models. We systematically compared how additive, multiplicative, and additomultiplicative cascade processes preserve multifractal structure under controlled conditions. Crucially, we introduced the coefficient of determination profile, r(2)(q), as a diagnostic measure that reveals the stability of scaling laws across moment orders q is an element of [-10, 10], distinguishing reliable multifractality in weak (q < 0) versus strong (q > 0) fluctuations. Using synthetic time series from each cascade type across seven generational depths and five noise environments (white, fractal, defractalizing, fractalizing, and mixed), we computed multifractal spectra f(alpha) and mapped r(2)(q) to assess scaling fidelity. Heatmaps revealed that additive cascades exhibited reliable scaling only for strong fluctuations, while multiplicative cascades maintained structure only near moderate q. In stark contrast, additomultiplicative cascades sustained consistently high r(2) across the full q-range and all noise conditions, demonstrating robust, symmetric multifractal scaling. This performance proved remarkably insensitive to noise type, confirming that cascade structure - not input statistics - determines scaling reliability. Only hybrid cascades captured both the finegrained regulatory control and burst-like adaptations characteristic of physiological processes. An illustrative analysis of heart rate variability data provided preliminary evidence that such additomultiplicative structures may constitute a plausible generative mechanism for biological multifractality. Our findings establish the r(2)(q) profile as a powerful diagnostic for multifractal model evaluation and identify hybrid cascade dynamics as uniquely capable of sustaining the dual regulatory demands of precision and adaptability across fluctuation intensities.

Calcareous nannofossil biostratigraphy has been investigated for Upper Cretaceous and lowermost Paleocene deposits in the Garab section located on the northeastern limb of the Kabir Kuh Anticline, Zagros Basin (Iran). The results reveal a relatively complete record that spans the Cenomanian to Danian stages. The base of the section contains Eiffellithus turriseiffelii, implying placement in or above the UC0 Biozone, and the occurrence of Corollithion kennedyi at 68.8 m confirms placement in the Cenomanian. An unconformity is suggested by the missing UC15a-b Biozone in the upper Campanian Gurpi Formation. The Cenomanian/Turonian Boundary (CTB) and Oceanic Anoxic Event 2 (OAE2) is characterized by abundant small taxa including Biscutum constans, Discorhabdus ignotus, and Zeugrhabdotus noeliae, among which the last two taxa are indicators of surface-water fertility during OAE2. The Cretaceous/ Paleogene Boundary (KPB) is marked by an increase of abundance of calcareous nannofossils such as Braarudosphaera bigelowii and Neobiscutum spp. and a rapid increase of calcareous dinoflagellates. Our results document high nannofossil productivity during the OAE2, as observed in other Tethyan locations, and rapid turnover and proliferation of disaster taxa such as Braarudosphaera bigelowii, and Neobiscutum spp. at the KPB. These results significantly enhance our understanding of these geological events and suggest that the Garab section is a strong candidate for further study of both the Cenomanian/Turonian boundary and K/Pg boundary. (c) 2025 Elsevier Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Michael T. Turvey viewed perceptual facility with words as a nonlinear prestress of whole-body synergies, forming a multifractal tensegrity rather than a computational cognitive mechanism. This reanalysis of young adults completing an upright-postural Stroop-like conjunction search links three aspects of multifractal synergies to the cognitive processes involved in the visual word search. First, searching tightly constrained task space benefits from reducing multifractal postural variability. Visual search for incongruently colored words occurred with less multifractal nonlinearity in the postural center of pressure (CoP), particularly for targets within a narrow visual angle. Second, physical constraint or destabilization requires compensatory changes in multifractal variability elsewhere. Restraining stance led successful search to become associated with increased multifractal nonlinearity in movement fluctuations at the head and clavicle. Third, applying task constraints that narrow search in the visual field links search performance with multifractal variability higher up in the body, i.e. closer to the narrowed search. Searching for inverse-incongruent words (e.g. a red-colored "blue" instead of a blue-colored "red") benefited from the reduction of multifractal nonlinearity in clavicle rather than in CoP displacement. Multi-joint synergies of multifractal nonlinear interactions support visual-word search by responding to or imposing constraints and reorganizing in response to intentional shifts.