Search Results (593)

Background/Objectives: Stroke often results in lasting upper limb deficits. Mirror visual feedback (MVF) supports motor recovery, and electromyography-triggered electrical stimulation (ES) could enhance engagement. However, the effects in healthy older adults, age-matched to typical patient cohorts, remain insufficiently understood. We tested MVF and MVF + ES using functional near-infrared spectroscopy. Methods: Seventeen right-handed older adults performed left-wrist flexion under three visual conditions: circle fixation, viewing the right hand at rest, and mirror viewing, with/without electrical stimulation to the right-wrist flexors time-locked to left-forearm electromyography. Oxygenated hemoglobin (oxy-Hb) was recorded over the bilateral inferior frontal gyrus (IFG), precentral gyrus (PrG), postcentral gyrus (PoG), supramarginal gyrus (SMG), superior parietal lobule (SPL), and supplementary motor area. Effects were assessed with linear mixed-effects models (stimulation × visual condition); pairwise comparisons of estimated marginal means used Fisher’s least significant difference. Left-forearm electromyography verified comparable effort across conditions. Results: Linear mixed-effects models revealed left-lateralized increases in oxy-Hb, most prominently under mirror viewing with stimulation. Post hoc tests showed high oxy-Hb in the left IFG, PrG, PoG, SMG, and SMA. The left EMG did not differ. Conclusions: In healthy older adults, MVF paired with EMG-triggered ES enhances frontoparietal–motor engagement beyond MVF alone, with recruitment shaped by visuo–proprioceptive congruence. These findings support mechanistic plausibility and motivate dose–response optimization and patient-focused trials testing behavioral transfer in stroke. Full article

Background: Hearing and cognition decline with age. Hearing is now considered an independent risk factor for later cognitive impairment. Computerized cognitive auditory training is being discussed as a possible adjunctive therapy approach. Objectives: The aim of this exploratory study is to investigate how the success of a computer-based cognitive auditory training (CCAT) can be measured. For this purpose, the influence of a CCAT on different dimensions of hearing and cognition was determined. Materials and Methods: 23 subjects between 52 and 77 years old were recruited with normacusis to moderate hearing loss. They underwent 40 digital training lessons at home. Before, during, and after completion, concentration ability with the d2-R, memory (VLMT), subjective hearing impairment (HHI), hearing quality (SSQ12), listening effort in noise (ACALES), and speech understanding in noise (GÖSA) were measured. Results and Discussion: In this uncontrolled, non-randomized study, one of the main findings was that cognitive dimensions, namely processing speed, improved by 12.11 ± 16.40 points (p = 0.006), and concentration performance improved by 12.56 ± 13.50 points (p = 0.001), which were not directly trained in CCAT. Learning performance also improved slightly by 4.00 ± 7.00 (p = 0.019). Subjective hearing handicap significantly reduced by 10.70 ± 12.38 (p = 0.001). There were no significant changes in the SSQ-12 (p = 0.979). Hearing effort improved by 1.79 ± 2.13 dB SPL (p = 0.001), 1.75 ± 2.09 (p = 0.001), and 3.32 ± 3.27 dB (p < 0.001), respectively. Speech understanding in noise did not improve significantly. CCAT is likely to improve several dimensions of hearing and cognition. Controlled future studies are needed to investigate its efficacy. Full article

Background: The microphone & receiver-in-ear (M&RIE) integrates two traditional hearing aid microphones, while an additional in-ear microphone helps preserve natural sound perception. However, the impact of this third microphone on hearing aid amplification remains unclear in patients with moderate hearing loss. Methods: In this prospective crossover study, thirty-nine participants with moderate hearing loss and no prior hearing-aid use were randomly assigned to be sequentially fitted with both traditional and M&RIE receivers. The abbreviated profile of hearing aid benefit (APHAB) and word recognition score (WRS) were assessed. Audiological amplification was evaluated using real-ear measurements to determine whether a third in-ear microphone limits real-ear gain. Results: WRSs and APHAB scores showed no significant differences between the standard and M&RIE receivers. In addition, real-ear measurements across all frequencies and earplug types revealed no significant differences in real-ear insertion gain between the two receivers at a conversational level (65 dB SPL). Conclusions: The M&RIE provides amplification comparable to that of the standard receiver while preserving natural sound cues without significant audiological disadvantages. Full article

Background: Bacterial resistance to antibiotics continues to rise globally, posing a significant public health challenge and incurring substantial social and economic burdens. In response, the World Health Organization (WHO) has published a list of priority pathogens for which effective treatment options are critically limited. Several antibiotics are categorized as Gram-positive-only (GPO) agents due to their lack of activity against Gram-negative species. Although these compounds often target conserved bacterial processes, their limited spectrum is largely attributed to poor penetration of the Gram-negative outer membrane (OM). Results: In this study, we designed and synthesized a series of adarotene-derived compounds to evaluate the impact of introducing positively charged groups on their interaction with the Gram-negative OM. One of the newly synthesized derivatives, SPL 207, displayed minimum inhibitory concentration (MIC) values ranging from 8 to 64 µM against a panel of Gram-positive and Gram-negative bacteria. The ability of SPL207 to disrupt outer and inner membrane permeability was evaluated using fluorescence assays and confocal microscopy, revealing that the compound compromises membrane integrity across all tested Gram-negative bacteria. Strong synergistic activity was observed in combination with colistin against three P. aeruginosa colistin-resistant strains. Atomistic details of membrane interference were elucidated by molecular dynamics (MD) simulations, with SPL207 clearly acting as a membrane destabilizer by enhancing Ca²⁺ ions diffusion and lipids destabilization. Conclusions: Although the observed MIC values remain above clinically acceptable thresholds, these findings provide a promising proof of concept. The further structural optimization of adarotene derivatives may yield novel broad-spectrum agents with improved antimicrobial potency against MDR pathogens. Full article

A disc-shaped double-layer shell structure reinforced by stiffeners is introduced for underwater gliders. Based on the finite element method integrated with automatic matching layer (FEM/AML) technology and the direct boundary element method (DBEM), the acoustic response of a disc-shaped double-layer shell with six longitudinal ribs within the frequency range of 10–500 Hz is obtained. The resonant frequencies of the sound pressure level (SPL) correlate with the structural–acoustic modes. At resonance frequencies, the acoustic directivity and spatial sound pressure distribution of the double-layer shell exhibit symmetry relative to the mid-cross-section. The influence of longitudinal rib counts on vibro-acoustic behavior is investigated. The analysis results of frequency–spatial spectrum for radiated sound pressure reveal that the resonant frequencies migrate to the mid-high frequency with increases in the longitudinal rib quantity. Full article

Methane emissions (CH₄-em) from dairy cows are a major environmental concern, contributing to greenhouse gases and energy loss in dairy cows. This study implemented advanced data analysis techniques to understand how different diet ingredients and production traits in dairy production systems can affect methane emissions. We analyzed a comprehensive meta dataset compiled from 225 peer-reviewed studies including 303 observations across multiple traits, using Bayesian networks and various machine learning models to explore the relationships between MEs, diet chemical ingredients, and production traits in dairy cattle. Eight models were applied, including linear models (OLS, LASSO, ridge, elastic net) and non-linear models (PLSR, spline regression, support vector machine, Gaussian process), to assess predictive performance. CH₄-em showed correlations ranged from −0.43 (with diet starch; STR) to 0.50 (with neutral detergent fiber; NDF) for diet-related factors, and 0.18 (with body weight; BW) to 0.29 (with milk yield; MY) for production traits. Also, Bayesian network analysis indicated that CH₄-em was a downstream variable for diet-related factors and an upstream variable for production traits. Additionally, the likelihood ratio test identified NDF as significant variable among the diet-related factors, while MY and milk fat (FAT) were crucial for production traits. non-linear models, particularly spline regression (SPL) and Gaussian process (GP), outperformed linear models in predicting CH₄-em. For production traits, support vector machine (SVM) and GP models showed superior predictive capabilities. Model performance was evaluated using R² and mean squared error (MSE) metrics. We found that while larger cows emitted more methane overall, they were generally more efficient, as methane intensity decreased with increasing MY regardless of body size. These findings offer valuable insights for developing sustainable methane mitigation strategies in dairy cattle production. Full article

Continuous authentication allows devices to keep checking that the active user is still the rightful owner instead of relying on a single login. However, current methods can be tricked by forging faces, revealing personal data, or draining the battery. Additionally, the environment where the user plays a vital role in determining the user’s online security. Thanks to several security attacks, such as impersonation and replay, the user or the device can easily be compromised. We present a lightweight system that pairs face recognition with complex environmental sensing, i.e., the phone validates the user when the surrounding light or noise changes. A convolutional network turns each captured face into a 128-bit code, which is combined with a random “nonce” and protected by hashing. A camera–microphone module monitors light and sound to decide when to sample again, reducing unnecessary checks. We verified the protocol with formal security tools (Scyther v1.1.3.) and confirmed resistance to replay, interception, deepfake, and impersonation attacks. Across 2700 authentication cycles on a Snapdragon 778G testbed, the median decision time decreased from 61.2 ± 3.4 ms to 42.3 ± 2.1 ms (p < 0.01, paired t-test). Data usage per authentication cycle fell by an average of 24.7% ± 1.8%, and mean energy consumption per cycle decreased from 21.3 mJ to 19.8 mJ (∆ = 6.6 mJ, 95% CI: 5.9–7.2). These differences were consistent across varying lighting (≤50, 50–300, >300 lux) and noise conditions (30–55 dB SPL). These results show that smart-sensor-triggered face recognition can offer secure and energy-efficient continuous verification, supporting smart imaging and deep-learning-based face recognition. Full article

The warmer air resulting from climate change reduces the lift force on a departing aircraft, potentially reducing its climb angle and causing more engine noise near the airport. Here, we study this phenomenon at a selection of 30 European airports in northern hemisphere summer (June–July–August). We first formulate and verify a low-complexity model of noise propagation around airports, although we emphasise that our high-level results do not explicitly depend on this agreement. The model includes anisotropic noise propagation, atmospheric absorption, and the ability to model the noise emissions from multiple engines. We study the Airbus A320, but the method could be straightforwardly generalised to other aircraft. We refer to the model as an emulator since (using Latin hypercube parameter sampling) it mimics a more comprehensive model against which it is verified. The model is used to calculate the area enclosed by the 50 dB SPL (sound pressure level) contour, $A_{50}$, which agrees well with a similar metric (using the day–evening–night sound level, $L_{\mathrm{den}}$) from the verification target, $\mathcal{A}$. Using temperature and pressure data from IPCC simulations of future climate, and using a straightforward relation between climb angle and air density, we assess how climate change could affect climb angles by mid-century (2035–2064). The value of $A_{50}$ is obtained by efficiently covarying (1) the engine noise at 10 m from the engines and (2) the climb angle under ‘historical’ conditions (1985–2014). The median values (across 10 climate models) of climb angle reduction in the future warmer climate are around 1–3% (depending on the airport and climate model used), but individual days can show values as high as 7.5% for the most extreme warming scenarios. By considering the variation in the absorption coefficient of the air with frequency, we find that the number of people affected by noise pollution could increase by up to 4%—as much as 2500 people for the most highly populated areas—by mid-century and that these changes are maximised for the most damaging and psychologically ‘annoying’ (low) frequencies. Full article

Background: Action video games—particularly first-person-shooter (FPS), real-time-strategy (RTS), multiplayer-online-battle-arena (MOBA), and battle-royale (BR) titles—have been linked to enhanced visuospatial skills, yet their impact on brain structure remains unclear. Purpose: To examine, using a cross-sectional design, whether long-term exposure to high-speed genres is associated with variations in cortical thickness and white matter microstructure. Methods: Structural and diffusion MRI were acquired from 27 video-game players (VGPs) and 19 non-video-game players (NVGPs). FreeSurfer-derived cortical thickness and DSI-Studio quantitative anisotropy (QA) were compared between groups, co-varying for intracranial volume. All p-values were Holm–Bonferroni- and FDR-corrected; bootstrap 95% CIs are reported. Results: VGPs showed greater cortical thickness in right inferior and superior parietal, supramarginal, and precuneus cortices (η_p² = 0.12–0.21) and higher QA along right SOG–SPL and left SOG–IPL tracts. Conclusions: Frequent action gaming is associated with greater cortical thickness in the dorsal stream and enhanced occipito-parietal connectivity. However, causal inference is precluded; longitudinal work is warranted. Full article

The miR156 family, crucial for phase transition and stress responses in plants, remains functionally uncharacterized in the ecologically and commercially important gymnosperm Larix kaempferi. This study systematically investigated L. kaempferi miR156 through phylogenetic analysis, structural prediction, expression profiling during somatic embryogenesis, and heterologous functional validation in Arabidopsis. Four MIR156 family members (LkMIR156s) were identified in Larix kaempferi, each with a characteristic stem-loop structure and highly conserved mature sequences. Computational predictions indicated that these LkMIR156s target four LkSPL family genes (LkSPL1, LkSPL2, LkSPL3, and LkSPL9). qRT-PCR analysis showed that mature LkmiR156s expression remained relatively low during early embryonic development but was significantly upregulated at the cotyledonary stage (21–42 days). Precursor transcript levels peaked earlier (around 28 days) than those of the mature LkmiR156, which remained highly expressed throughout cotyledonary embryo development. This sustained high expression coincided with cotyledon morphogenesis and embryonic dormancy. Functional validation via heterologous overexpression of LkMIR156b1 in Arabidopsis resulted in increased rosette leaf numbers (42.86% ± 6.19%) and individual leaf area (54.90% ± 6.86%), phenotypically consistent with the established role of miR156 in growth regulation. This study reveals the temporal expression dynamics of LkmiR156s during L. kaempferi somatic embryogenesis and its coordinated expression patterns with cotyledon development and embryonic dormancy. The functional conservation of the miR156-SPL module was confirmed in a model plant, providing key molecular insights into the developmental regulatory network of conifers. These findings offer potential strategies for optimizing somatic embryogenesis techniques in conifer species. Full article

People’s perceptions of architectural spaces are shaped by multiple senses, including vision and hearing. While vision has received extensive attention, hearing is often overlooked in architectural design, with a primary focus on sound insulation and noise reduction rather than on using acoustics to enhance spatial experience. Therefore, this study aims to investigate the impact of acoustic environments on two key spatial perceptions: Spaciousness and transparency. Two laboratory experiments were conducted with 60 participants. Thirty subjects evaluated 96 audiovisual stimuli for perceived spaciousness, and another 30 subjects assessed 128 audiovisual stimuli for perceived transparency. The results indicate that sound type significantly affects perceived spaciousness, while sound type and sound pressure level (SPL) significantly influence perceived transparency. Reverberation time (RT, T60) had no effect on either spatial perception. Interaction analysis further revealed that sound type affects transparency across different space sizes and window proportions, while SPL only influences small spaces and standard window proportions, with transparency decreasing as SPL increases. Mediation analysis showed that the effects of sound type on both spaciousness and transparency are partially mediated by subjective spatial perceptions, such as building environment preference and alignment with the outdoor environment. These findings emphasize the importance of integrating acoustic considerations into architectural design, which can enhance spatial experiences and provide valuable insights for future design practices. Full article

This study presents a semi-empirical approach to generalizing the acoustic radiation generated by serrated airfoil configurations, based on small-scale aerodynamic/acoustic experiments and functional regression techniques. In the context of passive noise reduction strategies, such as leading-edge and trailing-edge serrations, acoustic measurements are performed in a controlled subsonic wind tunnel environment. Sound pressure level (SPL) spectra and acoustic power metrics are acquired for various geometric configurations and flow conditions. These spectral data are then analyzed using regression-based modeling techniques—linear, quadratic, logarithmic, and exponential forms—to capture the dependence of acoustic emission on key geometric and flow-related variables (e.g., serration amplitude, wavelength, angle of attack), without relying explicitly on predefined nondimensional numbers. The resulting predictive models aim to describe SPL behavior across relevant frequency bands (e.g., broadband or 1/3 octave) and to extrapolate acoustic trends for configurations beyond those tested. The proposed methodology allows for the identification of compact functional relationships between configuration parameters and acoustic output, offering a practical tool for the preliminary design and optimization of low-noise serrated profiles. The findings are intended to support both physical understanding and engineering application, bridging experimental data and parametric acoustic modeling in aerodynamic noise control. Full article

N, as plants’ most essential nutrient, profoundly shapes root system architecture (RSA), with LRs being preferentially regulated. This review synthesizes the intricate molecular mechanisms underpinning N sensing, signaling, and its integration into developmental pathways governing LR initiation, primordium formation, emergence, and elongation. We delve deeply into the roles of specific transporters (NRT1.1, nitrate transporter 2.1 (NRT2.1)), transcription factors (Arabidopsis nitrate regulated 1 (ANR1), NLP7, TGACG motif-binding factor (TGA), squamosa promoter-binding protein-like 9 (SPL9)) and intricate hormone signaling networks (auxin, abscisic acid, cytokinins, ethylene) modulated by varying N availability (deficiency, sufficiency, excess) and chemical forms (NO₃⁻, NH₄⁺, organic N). Emphasis is placed on the systemic signaling pathways, including peptide-mediated long-distance communication (CEP—C-terminally encoded peptide receptor 1 (CEPR1)) and the critical role of the shoot in modulating root responses. Furthermore, we explore the emerging significance of carbon–nitrogen (C/N) balance, post-translational modifications (ubiquitination, phosphorylation), epigenetic regulation, and the complex interplay with other nutrients (phosphorus (P), sulfur (S)) and environmental factors in shaping N-dependent LR plasticity. Recent advances utilizing single-cell transcriptomics and advanced imaging reveal unprecedented cellular heterogeneity in LR responses to N. Understanding this sophisticated regulatory network is paramount for developing strategies to enhance nitrogen use efficiency (NUE) in crops. This synthesis underscores how N acts as a master regulator, dynamically rewiring developmental programs through molecular hubs that synchronize nutrient sensing with root morphogenesis—a key adaptive strategy for resource acquisition in heterogeneous soils. Full article

To investigate the effects of clearance variations induced by back wear ring wear on internal flow and noise within centrifugal pumps at the design flow rate (Q_o = 25 m³/h), a combined Computational Fluid Dynamics (CFD) and Acoustic Finite Element Method (FEM) approach was employed. The SST-SAS turbulence model and Lighthill’s acoustic analogy, were applied to simulate the internal flow and acoustic fields, respectively, across four different clearance values. The impact laws of various back wear-ring clearances on flow-induced noise were analyzed. The results indicate that the head and efficiency of the centrifugal pump gradually decrease with the increase in the back wear-ring clearance. When the clearance reaches 1.05 mm, the head drops by 4.35% and the efficiency decreases by 14.86%. The radial force on the impeller decreases, while the axial force increases and its direction reverses by 180 degrees. The acoustic source strength at the rotor–stator interface, near the volute tongue, and at the outlet of the back wear ring increases with larger clearance; furthermore, high-sound-source regions expand around the balance holes and near the impeller suction side. The dominant SPL frequency for all clearance cases was the blade passing frequency (BPF). As clearance increases, the overall SPL curve shifts upwards; however, the variation gradient decreases noticeably when the clearance exceeds 0.75 mm. The overall internal SPL increases, with the total SPL under 1.05 mm being 1.8% higher than that under 0.15 mm. In total, the optimal back ring clearance is 0.45 mm, which achieves a 38% noise reduction while maintaining a 97.9% head capacity. Full article

This study explores the aeroacoustic influence of leading-edge serrations applied to stator blades subjected to turbulent inflow, which is representative of rotor–stator interaction in turbomachinery. A set of serrated geometries—75 mm span, with up to 9 teeth corresponding to 10% chord amplitude—was fabricated via 3D printing and tested experimentally in a dedicated aeroacoustic facility at COMOTI. The turbulent inflow was generated using a passive grid, and far-field acoustic data were acquired using a semicircular microphone array placed in multiple inclined planes covering 15°–90° elevation and 0–180° azimuthal angles. The analysis combined power spectral density and autocorrelation techniques to extract turbulence-related quantities, such as integral length scale and velocity fluctuations. Beamforming methods were applied to reconstruct spatial distributions of sound pressure level (SPL), complemented by polar directivity curves to assess angular effects. Compared to the reference case, configurations with serrations demonstrated broadband noise reductions between 2 and 6 dB in the mid- and high-frequency range (1–4 kHz), with spatial consistency observed across measurement planes. The results extend the existing literature by linking turbulence properties to spatially resolved acoustic maps, offering new insights into the directional effects of serrated stator blades. Full article