Search Results (21,856)

This study addresses specific gaps in current research on user-experience interface design for news and information apps targeted at elderly users, particularly in the context of human factors and ergonomics. To investigate how interface design features of mobile news clients affect the cognitive load of elderly users, an in-depth analysis was conducted using a combination of objective eye movement tests and subjective evaluation scales. Mobile news client interfaces with systematically varied visual complexity were designed by orthogonally manipulating three core elements identified from top-ranked Chinese news apps and prior literature, and within-subject repeated experiments were performed to collect subjective cognitive load data, objective eye movement data, and behavioral data, validating the proposed hypothesis model. The results indicate that the visual complexity of mobile news client interfaces significantly impacts the cognitive load of elderly users, with keyword color substantially modulating this effect. These findings contribute to the knowledge base on mobile news client interface design for elderly users and provide practical recommendations for designers to create more equitable interfaces, enhancing usability for this demographic. Full article

The visibility of vertical road signs is a crucial factor for driving safety, especially in low-light conditions. The retroreflectivity of signs is imperative to ensure that drivers are able to perceive the information in a timely manner. However, the effectiveness of signs can be compromised by factors such as material degradation, wear and tear, and dirt on the surface. The objective of this study is to analyze how different surface conditions and different levels of retroreflectivity of vertical signs affect users’ perception and driving behavior in a real controlled environment. A total of twenty-five volunteers undertook the same road test twice. During the initial trial, the subjects encountered signs with a Class II retro-reflective film (EN 12899-1:2007), and during the second trial, they encountered the same signs in the same positions as the first trial but with varied characteristics and additional factors such as dirt, water, and degradation. Through a Mobile Eye Tracker and a Racelogic Video Vbox, it was possible to investigate the alterations in the visual and kinematic behavior of participants across the two tests. The statistical analysis was conducted using the Wilcoxon test, Spearman’s correlation and regression analysis. The analysis revealed that the signal with a dirty surface had the most significant impact on participants’ perception, showing a substantial reduction in the distance of the first fixation (−15%), a decrease in the number of fixations (−37%), and an increase in the time required for it to be perceived (+40%). This study demonstrates that the maintenance of road sign surfaces is a critical factor in their effectiveness and is as influential as the level of retroreflectivity of the material. Full article

Background/Objectives: The pharyngeal microbiota plays a critical role in respiratory health by supporting immune modulation, colonization resistance, and metabolic functions. Disruptions in this microbial ecosystem are associated with respiratory diseases; however, standard diagnostics often target individual pathogens, overlooking overall microbial dynamics. This study investigates the composition and diversity of the pharyngeal microbiota in three populations: individuals with pre-COPD (with and without concurrent acute respiratory infection [ARI]) and those with stable COPD. Methods: Pharyngeal swabs were analyzed using 16S rDNA sequencing on the Illumina MiSeq platform. Taxonomic and functional profiles were generated with MicrobAT^®, while microbial diversity was evaluated using the Shannon index and PERMANOVA. Group differences in microbiota composition were assessed via Kruskal–Wallis tests and robust PCA. The sample size was estimated at 8 subjects per group to detect significant differences (α = 0.05, 80% power, SD ≈ 20). Results: Twenty-nine swabs were collected: 11 from pre-COPD subjects (PC), 9 from ARI patients receiving antibiotics, and 9 from individuals with stable severe COPD. Microbial diversity was preserved in the PC group (100%) but markedly reduced in ARI (25%) and COPD (15%). Microbiota composition differed significantly across groups (R² = 0.371, p = 0.001), particularly at the phylum level. Functional analysis revealed minimal deficits in PC (<10%) but major impairments in ARI (81%) and COPD (56%), indicating reduced microbial functional capacity. Conclusions: Broad-spectrum microbial analysis highlights the importance of assessing pharyngeal microbiota beyond traditional pathogen detection, offering potential for innovative diagnostic and therapeutic approaches. Full article

The utilization of tuned mass dampers (TMDs) is subject to numerous restrictions. In general, the control performance of a TMD is limited by the ratio of the mass block to the effective mass of the main structure (mass ratio). These dampers also require precise tuning to the required target frequency to absorb the host structure’s vibrational energy. Due to their unique geometric gradient forms, acoustic black hole (ABH) structures can slow the propagation speed of bending waves and concentrate them at the apex, thereby significantly enhancing the suppression of broadband vibration. In this paper, we combine the above two methods to form a single novel device named ABH-TMD. Firstly, a mechanical model of the proposed device is established. The bending-wave control equation is derived, followed by a numerical analysis and experimental tests for further verification. Secondly, a series of numerical simulations are conducted. The response of the controlled beam is determined based on time histories and the frequency domain. Lastly, parameter analysis is carried out to investigate the control’s effectiveness. Based on the numerical and experimental results, we conclude that the proposed ABH-TMD can successfully concentrate elastic waves, thereby surpassing the traditional TMD under broadband frequency conditions. Full article

Subjective assessments of air pollution annoyance reveal that individuals’ focus on specific risks is influenced by their attachment to place, beliefs, values, and behavior rather than the composition or toxic effects of air pollutants. Additionally, the social context plays a role in shaping how communities react to and perceive air pollution impacts. This study examines residents’ environmental perceptions regarding the effects of settleable particles before and after the interruption of a large industrial source in the southern region of Espírito Santo, Brazil (South America). A second objective was to model the relationship between air pollution annoyance and other perceived variables under both scenarios. Data were collected through surveys conducted before and after the interruption of the industrial plant. The Pearson chi-square test and ordinal logistic regression model analyzed the data. Results indicate a shift in residents’ concerns with a focus on social and well-being issues. We also found a small number of items relating to dust annoyance and home ownership that can be used to predict the air pollution impact for individual community members. The findings show that settleable particles are directly perceived by exposed populations and significantly affect community health and quality of life. Full article

Background/Objectives: Facial nerve injury from conditions such as Bell’s palsy, trauma, surgery, and infection leads to facial asymmetry and motor deficits. Axotomy models reproduce peripheral nerve disruption and consequent motor impairment. To compare the effects of forward versus reverse autologous nerve suturing on neural regeneration and motor recovery within the facial nucleus after axotomy. Methods: In rats subjected to facial nerve axotomy, motor recovery was assessed at 8 weeks using whisker movement and blink reflex tests. Immunohistochemistry quantified choline acetyltransferase (ChAT), sirtuin 1 (SIRT1), and Iba-1 as indices of cholinergic function, cellular stress/inflammation modulation, and microglial activation in the facial nucleus. Results: Axotomy significantly reduced whisker and blink scores compared with sham. Both forward and reverse suturing significantly improved these behavioral outcomes versus axotomy. Within the facial nucleus, axotomy decreased ChAT- and SIRT1-positive cells and increased Iba-1 expression, while both suturing techniques increased ChAT and SIRT1 and reduced Iba-1. These changes suggest enhanced cholinergic function, mitigation of stress/inflammatory responses, and attenuation of microglial activation following repair. Conclusions: Forward and reverse suturing were each associated with improved motor function and favorable molecular and cellular changes in the facial nucleus after facial nerve axotomy. These findings support the utility of surgical repair irrespective of graft orientation and highlight involvement of key pathways—cholinergic signaling, SIRT1-related regulation, and microglial activity—in nerve restoration. This work extends our previous study, which focused on peripheral nerve regeneration after forward and reverse suturing, by elucidating how graft orientation affects central facial nucleus responses. By integrating behavioral outcomes with ChAT, Iba-1, and SIRT1 expression, the present study provides novel insight into the central mechanisms underlying motor recovery after facial nerve repair and helps explain why comparable functional outcomes are achieved regardless of graft polarity. Full article

The complexity of the loading mode and action mechanism is demonstrated in the portal frame anti-uplift structure. The stress evolution process of the portal frame structure during the excavation of the upper foundation pit is revealed through in situ structural stress tests and numerical modeling analysis reflecting the small strain characteristics of stratum. The stress distribution of uplift piles and anti-floating plates is analyzed, with the axial force of piles and the development law of bending moment in plates being specifically examined. It is emphasized that the load of the uplift pile is generated by friction between the pile and soil caused by stratum floating, which is predominantly produced during the excavation of the upper block and the unloading of the surcharge. The pile 11# is observed to be under tension in the middle and compressed at both ends, with the extreme value of tensile stress of these 24 piles being located at 0.15 times the pile length below the top of the middle pile. The main loads of the anti-floating plate are identified as backfilling, foundation buoyancy, and lateral soil pressure. The lower part of the two pile spans is subjected to tension, while the upper part is under compression, with the bending moment extremes being located on the side where the frame is first formed. A significant increase in stiffness is exhibited by the frame structure after its formation, and the influence from the excavation of other blocks is markedly reduced. The most adverse condition is determined to occur during the integral removal of the upper surcharge. The reference value of these research results is confirmed for clarifying the stress mechanism of anti-uplift portal frame structures and optimizing key technical parameters in structural design and construction. Full article

The durability of concrete in immersed tunnels is critically influenced by the coupled effects of stress, seepage, and chemical erosion, particularly in inland water environments. However, the spatio-temporal evolution of mechanical property degradation under such multi-field coupling remains insufficiently quantified. Unlike previous studies focused on “load-ion” or “hydraulic pressure-ion” dual coupling, this work introduces a complete stress–seepage–chemical tri-coupling that incorporates the critical seepage effect, representing a fundamental expansion of the experimental scope to better simulate real-world conditions. This study investigates the degradation mechanisms of concrete in the Shunde Lungui Road inland immersed tunnel subjected to such coupled erosion. A novel aspect of our approach is the application of the micro-indentation technique to quantitatively characterize the spatio-temporal evolution of the local elastic modulus at an unprecedented spatial resolution (0.5 mm intervals), a dimension of analysis not achievable by conventional macro-scale testing. Key findings reveal that the mechanical properties of concrete exhibit an initial enhancement followed by deterioration. This behavior is attributed to the filling of pores by reaction products (gypsum, ettringite, and Friedel’s salt) in the short term, which subsequently induces microcracking as the volume of products exceeds the pore capacity. Furthermore, increasing hydro-mechanical loading significantly accelerates the erosion process. When the load increases from 1.596 kN to 3.718 kN, the influence range of elastic modulus variation expands by 9.2% (from 5.186 mm to 5.661 mm). To quantitatively describe this acceleration effect, a novel load-acceleration erosion coefficient is proposed. The erosion rate increases from 0.0688 mm/d to 0.0778 mm/d, yielding acceleration coefficients between 1.100 and 1.165, quantifying a 10–16.5% acceleration effect beyond what is typically captured in dual-coupling models. These quantitative results provide critical parameters for employing laboratory accelerated tests to evaluate the ionic erosion durability of concrete structures under various loading conditions, thereby contributing to more accurate service life predictions for engineering structures. Full article

Background/Objectives: Situations previously paired with drug use can become conditioned stimuli (i.e., physical stress or psychosocial stress) that elicit intense craving and relapse, even after prolonged abstinence. Previous studies have shown that pharmacological disruption of reconsolidation after memory reactivation could be promising for reducing pathological fear and stress-related responses. For this reason, the aim of this research was to examine the role of β-AR in the retrieval of aversive memories through the potential of β-AR antagonism to mitigate the effects of exposure to stressful stimuli. Methods: This question was addressed using a model to assess the re-emergence of an aversive contextual memory induced by both physical stressors (restraint and tail-pinch) and psychosocial stress (social defeat) in morphine- or saline-treated mice previously subjected to a conditioned place aversion (CPA) paradigm, in which naloxone was administered to precipitate opioid withdrawal. To assess the effects of propranolol on aversive memories related to opioid addiction, the number of chamber crossings and the time spent in the naloxone-paired compartment were measured. Results: Our results showed that morphine-treated mice spent significantly less time in the naloxone-paired chamber than saline mice during the post-test and after exposure to stressful stimuli, than during the pre-test, showing an effect for aversive memories in addiction. In contrast, when propranolol was administered intraperitoneally 30 min before the exposure to both social and physical stress, the time spent enhanced significantly (p < 0.01), supporting a role for propranolol in addiction-related memories. Conclusions: These results suggest that propranolol could attenuate the aversive memories that may contribute to relapse to opioid addiction. Full article

Speech is one of the earliest-affected modalities in Parkinson’s disease (PD). For more reliable PD evaluation, speech-based telediagnosis studies often use multiple samples from the same subject to capture variability in speech recordings. However, many existing studies split samples—rather than subjects—between training and testing, creating a biased experimental setup that allows data (samples) from the same subject to appear in both sets. This raises concerns for reliable PD evaluation due to data leakage, which results in over-optimistic performance (often close to 100%). In addition, detecting subtle vocal impairments from speech recordings using multiple feature extraction techniques often increases data dimensionality, although only some features are discriminative while others are redundant or non-informative. To address this and build a reliable speech-based PD telediagnosis system, the key contributions of this work are two-fold: (1) a uniform (fair) experimental setup employing subject-wise symmetric (stratified) splitting in 5-fold cross-validation to ensure better generalization in PD prediction, and (2) a novel hybrid data complexity-aware (HDC) feature selection method that improves class separability. This work further contributes to the research community by releasing a publicly accessible five-fold benchmark version of the Parkinson’s speech dataset for consistent and reproducible evaluation. The proposed HDC method analyzes multiple aspects of class separability to select discriminative features, resulting in reduced data complexity in the feature space. In particular, it uses data complexity measures (F4, F1, F3) to assess minimal feature overlap and ReliefF to evaluate the separation of borderline points. Experimental results show that the top-50 discriminative features selected by the proposed HDC outperform existing feature selection algorithms on five out of six classifiers, achieving the highest performance with 0.86 accuracy, 0.70 G-mean, 0.91 F1-score, and 0.58 MCC using an SVM (RBF) classifier. Full article

Rigid pavements in marine airports are subjected to severe surface degradation due to the combined effects of salt erosion and repeated aircraft impact loading, which significantly reduces service life and operational safety. This study investigates the degradation behavior and underlying mechanisms governing the surface wear resistance of C40 concrete under simulated marine environmental and mechanical conditions. Specimens were first subjected to repeated drop-weight impact loading, after which abrasion tests were performed to quantify surface wear resistance. Microstructural evolution and corrosion products were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses. The results show that repeated impact loading significantly accelerates surface deterioration: after 60 abrasion cycles, cumulative mass loss increased by up to 23.6 g for specimens subjected to 80 impacts, while long-term water absorption rose by up to 7.52% due to impact-induced microcracking. In contrast, moderate salt-fog exposure initially enhanced wear resistance, as cumulative mass loss decreased from 18.1 g (unexposed) to 9.4 g after 30 cycles, attributable to pore filling by CaCO₃ and Friedel’s salt. However, prolonged exposure (40 cycles) reversed this trend, leading to strength loss. Under combined impact of salt-fog conditions, the wear resistance deteriorated more rapidly, and the transition from strengthening to weakening occurred earlier than under salt exposure alone, indicating a coupled degradation effect. These findings clarify the coupled chemical–mechanical deterioration mechanism of marine airport pavements and provide a scientific basis for durability design and maintenance optimization. Full article

Anterior cruciate ligament (ACL) rupture causes joint instability and increases the risk of osteoarthritis due to the ligament’s limited healing capacity. Silk, particularly from Bombyx mori, combines high cytocompatibility with robust biomechanical properties. Its main components are fibroin and sericin, with the latter usually being removed to reduce immunogenicity and improve biocompatibility. Silk threads were processed either as raw silk (designated as “untreated”) or subjected to a patented degumming procedure (DE102021118652A1) to obtain purified silk. Both variants were used alone or in combination with poly(L-lactic acid-co-caprolactone) (P(LA-CL)) fibers, yielding four scaffold groups: untreated silk, purified silk, untreated silk/P(LA-CL), and purified silk/P(LA-CL). Three-layer scaffolds were fabricated using a zigzag embroidery pattern. Structural analysis revealed scaffold porosity of ≈38% for silk, ≈46% for purified silk, and up to ≈70% for scaffolds containing P(LA-CL). Uniaxial tensile testing showed that purified silk scaffolds achieved the highest maximum force at break (≈684 N), whereas elongation at maximum force was limited in the hybrid scaffolds—silk/P(LA-CL) ≈28% and p-silk/P(LA-CL) ≈32%—despite the high intrinsic extensibility of P(LA-CL). All scaffolds supported cell adhesion and showed no cytotoxicity. P-silk and p-silk/P(LA-CL) scaffolds exhibited the highest fibroblast adherence and pronounced paxillin expression, indicating strong cell–material interactions. Gene expression of ligament-related ECM components and connexin 43 was maintained across all groups. These results demonstrate that embroidered silk fibroin scaffolds provide a reproducible architecture with tunable porosity and mechanical properties, supporting fibroblast colonization and ligament-specific ECM expression. Such scaffolds represent promising candidates for ACL tissue engineering and future graft development. Full article

Test anxiety is considered to affect individuals’ cognitive control and task performance, particularly in error monitoring. While previous research has explored the relationship between anxiety and cognitive performance, this study aims to investigate the impact of test anxiety and cognitive stress on error processing, focusing on changes in error-related negativity (ERN). Participants were divided into high test anxiety (HTA) and low test anxiety (LTA) groups based on their scores on the Test Anxiety Scale (TAS). Cognitive stress was induced by administering the Raven’s Standard Progressive Matrices test, accompanied by instructions that emphasized score comparison with others. Participants completed the Subjective Test Anxiety Scale (STAS), the Short State Anxiety Inventory (SSAI), and a Flanker task before and after the stress manipulation. The effectiveness of the stress manipulation was confirmed by significant increases in STAS and SSAI scores and changes in behavioral performance. EEG data were recorded to analyze ERN, correct-response negativity (CRN), and ΔERN (ERN minus the CRN) amplitudes. HTA individuals exhibited a trend toward larger ERN amplitudes than LTA counterparts, indicating heightened sensitivity to errors. However, no significant changes in ERN amplitudes were observed between pre- and post-stress conditions. CRN and ΔERN amplitudes also showed no significant differences across anxiety groups or stress conditions. ERN changes appear to be more closely related to trait test anxiety than to transient stress. Full article

Impressed current cathodic protection (ICCP) systems can experience acidification, which deteriorates the interface between the anode and the anode backfill mortar. This deterioration may necessitate premature intervention to remove and reinstate the backfill and, in some cases, replace the anode. If left unaddressed, acidification ultimately leads to debonding between the anode and the backfill mortar, resulting in the failure of the ICCP system. This paper presents the development of a specialised acid-resistant hybrid mortar designed for ICCP systems used to protect reinforced concrete bridges in marine environments. It also investigates the effects of acidification on the physical and mechanical properties of the proposed anode backfill mortars. Additionally, the study characterises acidification products from both field-extracted ICCP systems and laboratory-based accelerated testing, providing deeper insights into the acidification mechanisms. Novel mortar samples were subjected to varying concentrations of hydrochloric acid (HCl) under accelerated testing conditions. The incorporation of supplementary cementitious materials (SCMs), calcium sulfoaluminate (CSA) cement and zeolite significantly enhanced the strength and durability of the backfill mortars in acidic environments, while maintaining compliance with the electrical resistivity requirements (20–100 kΩ·cm) for ICCP systems. The lowest compressive strength loss observed in the developed hybrid mortar was 54% after 28 days of immersion in 5% HCl and 83% in 15% HCl. Microstructural analyses revealed that gypsum formation and chloride–sulphate competitive binding interactions are key mechanisms contributing to the improved acid resistance, particularly in CSA cement-containing formulations. Full article

Complexities are involved in testing an aircraft structure, including its size, which is essential for determining cost and feasibility. This paper focuses on the novelty of investigating the use of a scaled-down version of a full-scale aircraft wing and a test rig to predict the test rig’s structural response to the wing’s loading condition, thereby improving design and modelling techniques for the test rig. This paper also presents a methodology for sizing the test rig and the aircraft wing to perform structural tests on the wing. Numerical and experimental models subjected to various load cases are compared. This study begins by justifying the use of finite element analysis (FEA) for relevant parts of the test rig. A detailed explanation of the sizing method and its overall effect on the test rig is also provided. The results indicate a substantial similarity between the numerical and experimental models with respect to the stresses and deformation of the test specimen. Full article