Search Results (171)

Kinesthetic motor imagery (KMI), the mental rehearsal of a motor task without its actual performance, constitutes one of the most common techniques used for brain–computer interface (BCI) control for movement-related tasks. The effect of neural injury on motor cortical activity during execution and imagery remains under investigation in terms of activations, processing of motor onset, and BCI control. The current work aims to conduct a post hoc investigation of the event-related potential (ERP)-based processing of KMI during BCI control of anthropomorphic robotic arms by spinal cord injury (SCI) patients and healthy control participants in a completed clinical trial. For this purpose, we analyzed 14-channel electroencephalography (EEG) data from 10 patients with cervical SCI and 8 healthy individuals, recorded through Emotiv EPOC BCI, as the participants attempted to move anthropomorphic robotic arms using KMI. EEG data were pre-processed by band-pass filtering (8–30 Hz) and independent component analysis (ICA). ERPs were calculated at the sensor space, and analysis of variance (ANOVA) was used to determine potential differences between groups. Our results showed no statistically significant differences between SCI patients and healthy control groups regarding mean amplitude and latency (p < 0.05) across the recorded channels at various time points during stimulus presentation. Notably, no significant differences were observed in ERP components, except for the P200 component at the T8 channel. These findings suggest that brain circuits associated with motor planning and sensorimotor processes are not disrupted due to anatomical damage following SCI. The temporal dynamics of motor-related areas—particularly in channels like F3, FC5, and F7—indicate that essential motor imagery (MI) circuits remain functional. Limitations include the relatively small sample size that may hamper the generalization of our findings, the sensor-space analysis that restricts anatomical specificity and neurophysiological interpretations, and the use of a low-density EEG headset, lacking coverage over key motor regions. Non-invasive EEG-based BCI systems for motor rehabilitation in SCI patients could effectively leverage intact neural circuits to promote neuroplasticity and facilitate motor recovery. Future work should include validation against larger, longitudinal, high-density, source-space EEG datasets. Full article

The covalent conjugation of pharmaceutical compounds to polymeric carriers represents an effective strategy for enhancing drug properties, including improved bioavailability, targeted delivery, and sustained release, while reducing systemic toxicity and adverse effects. By exploiting the physicochemical characteristics of biopolymers—particularly molecular charge and weight—we engineered a polymeric platform for glucocorticoid delivery with precisely controlled parameters including particle size, surface charge, targeting capability, and release kinetics. This study reports a linker-free synthesis of hyaluronic acid-dexamethasone (HA-DEX) conjugates through Steglich esterification, catalyzed by 4-dimethylaminopyridine (DMAP), which facilitates the acylation of sterically hindered alcohols. The reaction specifically couples carboxyl groups of hyaluronic acid with the C21 hydroxyl group of dexamethasone. Incorporation of hydrophobic dexamethasone moieties induced self-assembly into nanoparticles featuring a hydrophobic core and negatively charged hydrophilic shell (−20 to −25 mV ζ-potential). In vitro characterization revealed pH-dependent release profiles, with 80–90% dexamethasone liberated in mildly acidic phosphate buffer (pH 5.2) versus 50–60% in phosphate-buffered saline (pH 7.4) over 35 days, demonstrating both sustained release and inflammation-responsive behavior. The conjugates exhibited potent anti-inflammatory activity in a human tumor necrosis factor-α (TNFα)-induced inflammation model. These findings position HA-DEX conjugates as promising candidates for targeted glucocorticoid delivery to specific anatomical sites including ocular, articular, and tympanic tissues, where their combination of CD44-targeting capability, enhanced permeability and retention effects, and stimulus-responsive release can optimize therapeutic outcomes while minimizing off-target effects. Full article

Incremental capacity analysis (ICA), where incremental charge (Q) movements associated with changes in potential are tracked, and cyclic voltammetry (CV), where current response to a linear voltage sweep is recorded, are used to investigate the properties of electrochemical systems. Electrochemical impedance spectroscopy (EIS), on the other hand, is a powerful, non-destructive technique that can be used to determine small-signal AC impedance over a wide frequency range. It is frequently used to design battery equivalent-circuit models. This manuscript explores the relationships between ICA, CV and EIS and demonstrates how sweep rate in CV is related to charging (C) rate in ICA. In addition, it shows the connection between observations linked to rate of charge movement in CV and ICA and intermittent, irregular behavior seen in EIS when performed on a battery. It also explains the use of an additional DC stimulus during EIS to ensure reliability of battery impedance data and to facilitate equivalent-circuit modeling, and suggests a method for obtaining data analogous to CV from a whole battery without risking its destruction. Full article

Cartilage tissue engineering (CTE) is an advancing field focused on developing biomimetic scaffolds to overcome cartilage’s inherently limited self-repair capacity. Smart hydrogels (SHs) have gained prominence among the various scaffold materials due to their ability to modulate cellular behavior through tunable mechanical and biochemical properties. These hydrogels respond dynamically to external stimuli, offering precise control over biological processes and facilitating targeted tissue regeneration. Recent advances in fabrication technologies have enabled the design of SHs with sophisticated architecture, improved mechanical strength, and enhanced biointegration. Key features such as injectability, controlled biodegradability, and stimulus-dependent release of biomolecules make them particularly suitable for regenerative applications. The incorporation of nanoparticles further improves mechanical performance and delivery capability. In addition, shape memory and self-healing properties contribute to the scaffolds’ resilience and adaptability in dynamic physiological environments. An emerging innovation in this area is integrating artificial intelligence (AI) and omics-based approaches that enable high-resolution profiling of cellular responses to engineered hydrogels. These data-driven tools support the rational design and optimization of hydrogel systems and allow the development of more effective and personalized scaffolds. The convergence of smart hydrogel technologies with omics insights represents a transformative step in regenerative medicine and offers promising strategies for restoring cartilage function. Full article

Background/Objectives: Environmental psychology has long investigated how exposure to natural versus urban environments influences cognitive processes, particularly attention. According to Attention Restoration Theory (ART), natural scenes promote involuntary attention and facilitate recovery from mental fatigue. In this study, we used a modified Posner cueing paradigm to assess how natural and urban backgrounds affect both exogenous (involuntary) and endogenous (voluntary) attention. To capture both behavioral and neural responses, the study collected reaction times (RTs) as a measure of task performance, alongside electrophysiological data (event-related potentials, ERPs: P1, N1, P2, N2, and P3) to explore underlying attentional processes. Methods: Participants completed a visuospatial task in which visual cues anticipated the appearance of a target stimulus, while background images depicting either natural or urban environments remained visible throughout. Attention was assessed under both valid (cue correctly predicts target location) and invalid (cue misleads target location) conditions. Results: The overall findings align with the existing literature: RTs were shorter in valid trials compared to invalid ones. No main facilitation effect from natural backgrounds was observed. However, participants showed slower RTs in invalid trials with natural backgrounds, which may support ART by suggesting that attention restoration could lead to slower responses in certain attentional scenarios. Electrophysiological data reinforced these behavioral results, revealing an increased N2 amplitude in the natural background invalid condition. Conclusions: Despite some limitations, this study provides novel insights into human–nature interactions, offering a fresh perspective on the complex relationship between environment and cognition. Full article

Background/Objectives: Intracranial macroelectrode implantation is a pivotal clinical tool in the evaluation of drug-resistant epilepsy, allowing further insights into the localization of the epileptogenic zone and the delineation of eloquent cortical regions through cortical stimulation. Additionally, it provides an avenue to study brain functions by analyzing cerebral responses during neuropsychological paradigms. By combining macroelectrodes with microelectrodes, which allow recording the activity of individual neurons or smaller neural clusters, recordings could provide deeper insights into neuronal microcircuits and the brain’s transitions in epilepsy and contribute to a better understanding of neuropsychological functions. In this study, one or two hybrid macro-micro electrodes were implanted in the anterior-inferior insular region in patients with refractory epilepsy. We report our experience and share some preliminary results; we also provide some recommendations regarding the implantation procedure for hybrid electrodes in the insular cortex. Methods: Stereoelectroencephalography was performed in 13 patients, with one or two hybrid macro-microelectrodes positioned in the insular region in each patient. Research neuropsychological paradigms could not be implemented in two patients for clinical reasons. In total, 23 hybrid macro-microelectrodes with eight microcontacts each were implanted, of which 20 were recorded. Spiking activity was detected and assessed using WaveClus3. Results: No spiking neural activity was detected in the microcontacts of the first seven patients. After iterative refinement during this process, successful recordings were obtained from 13 microcontacts in the anterior-inferior insula in the last four patients (13/64, 20.3%). Hybrid electrode implantation was uneventful with no complications. Obstacles included the absence of spiking activity signals, unsuccessful microwire dispersion, and the interference of environmental electrical noise in recordings. Conclusions: Human microelectrode recording presents a complex array of challenges; however, it holds the potential to facilitate a more comprehensive understanding of individual neuronal attributes and their specific stimulus responses. Full article

In the context of the global environment, the rapid advancement of Internet technology has facilitated a transition from traditional offline to online modes for corporate social responsibility (CSR) activities, leading to the emergence of virtual CSR co-creation initiatives. A crucial challenge for enterprises engaging in such activities lies in enhancing consumer participation and retention rates. This study constructs a mediation effect model incorporating emotional factors, interaction factors, social presence, and consumer willingness to participate, grounded in the Stimulus–Organism–Response (S-O-R) model. Based on data collected from 232 consumers in China, this study reveals that identification, enthusiasm, and satisfaction exert positive influences on consumer willingness to participate. Additionally, social presence positively affects willingness to participate and acts as a mediator between community platform interaction, offline interaction, and willingness to participate. Full article

Knowledge visualization has gained significant research attention for its potential to facilitate knowledge construction through interactive graphics while minimizing cognitive load during information processing. However, limited research has examined the integration of knowledge visualization within highly interactive mixed-reality environments and its effects on user experiences and science, technology, engineering, and mathematics (STEM) sustainability. Drawing on the cognitive-affective model of immersive learning, this study investigates how learners’ user experiences, elicited by mixed-reality features and usability, influence their sustainable engagement with STEM learning through knowledge-visualization tools framed within the stimulus–organism–response model. A novel mixed-reality learning system was developed, with the user interface designed using concept maps to graphically visualize concept nodes and their interconnected relationships. A total of 136 learners from two high schools in China participated in an experiment on frictional physics using this novel system. Using structural equation modeling, the collected data were analyzed with partial least squares. The findings demonstrate that mixed-reality features of knowledge visualization (featured by 3D graphics, interface design, and operational functions), as well as usability (featured by the perceived usefulness of the concept map, perceived ease of use, and perceived usefulness of the system), have positive significant impacts on user experience (represented by satisfaction, perceived enjoyment, and attitude). Subsequently, positive user experiences have positive significant impacts on learners’ sustained intention to engage with STEM education. Further mediating analysis provides empirical evidence that positive user experiences, acting as a psychological enabler, mediate the relationship between system design and behavioral intention. The research model explains 65.2% of the variance for system usability, 53.4% for satisfaction, 51.5% for perceived enjoyment, 54.9% for attitude, and 63.2% for continuance intention. By fostering positive user experiences in STEM learning, this study offers valuable insights for educators and practitioners seeking to implement effective interactive knowledge visualizations to support sustainable STEM education and immersive learning. Full article

This study combines innovation resistance theory, the stimulus–organism–response (SOR) framework, and the job demands–resources model to facilitate an in-depth exploration of the barriers faced by healthcare professionals and the psychological responses they exhibit when adopting AI-supported healthcare technologies. We conducted a questionnaire survey and obtained 296 valid responses from healthcare professionals to examine the relationship between resistance to AI-supported healthcare technologies and AI adoption behavioral intentions. Using the SOR framework as a basis, this study validated a serial mediation model with moderating effects, demonstrating that resistance to AI-supported healthcare technologies influenced AI adoption behavioral intentions through job resource, job demand, and levels of employee engagement. Further, this study sought to validate the relationship between age-moderated job resource and job demand in employees exhibiting resistance to AI-supported healthcare technologies and their associated AI adoption behavioral intentions. The results indicated that job resources, job demands, and employee engagement serially mediated the relationship between resistance to AI-supported healthcare technologies and AI adoption behavioral intentions. Additionally, age only exhibited significant moderating effects on the relationship between job demands in resistance to AI-supported healthcare technologies and AI adoption behavioral intentions. The findings of this study can aid in promoting the adoption of AI-supported healthcare technologies by healthcare professionals, generating new insights and broadening the scope and vision of existing literature. Full article

Sustainable leisure, shared among grandparents and grandchildren, provides multiple benefits, as it enhances contexts and bonds that foster personal, familiar, social and emotional development. In addition to this, it directly contributes to the achievement of the sustainable development goals, established in Agenda 2030. The objective was to examine, from the grandparents’ perspective, and taking into account their educational level, the links that exist among co-learning processes and the practice of sustainable intergenerational leisure and its evolution throughout the pandemic era. This project sought to combine quantitative (N = 350) and qualitative (N = 18) methodologies, using an ad hoc questionnaire and a discussion group, in different moments, before and after the pandemic. The SPSS 23.0 statistical program was used for quantitative analysis and the NVivo Release 1.6 software for the qualitative study. The results show that intergenerational co-learning is a motive and a relevant stimulus that encourages both generations to share these experiences in natural spaces, which brings them together and facilitates lifelong learning. It has been proven that, before the lockdown, sustainable leisure practices showed significant differences depending on the level of education of the older generation. This had an impact on participation in activities associated with different types of leisure, with a tendency to increase the practice as the level of education rises. Nevertheless, after the pandemic, a greater reduction has been observed in the practice of shared leisure activities among those with a higher educational level. Full article

Waterlogging stress significantly impacts the growth and productivity of crops. As a traditional oil crop, sesame (Sesamum indicum L.) suffers substantial damage due to waterlogging stress. However, the mechanism underlying waterlogging stress in sesame is still unclear. In this study, we investigated the physiological indicators of two sesame genotypes under waterlogging stress. The results revealed that the activity of antioxidant enzymes in sesame was affected, with the contents of malondialdehyde (MDA) and hydrogen peroxide (H₂O₂) significantly increased. Additionally, transcriptional analysis identified a total of 15,143 differentially expressed genes (DEGs). Among them, 759 DEGs exhibited consistent differential expression across all time points, representing the core waterlogging-responsive genes. Gene Ontology (GO) enrichment analysis indicated that the DEGs were primarily associated with hypoxia, stimulus response, and oxidoreductase enzyme activities. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that these DEGs were mainly enriched in the metabolic and biosynthesis of secondary metabolites, glycolysis/gluconeogenesis, phenylpropanoid biosynthesis, MAPK signaling pathway-plant, carbon fixation by Calvin cycle, plant hormone signal transduction, and plant-pathogen interaction pathways. Furthermore, transcription factors (TFs) such as AP2/ERF, bHLH, bZIP, and WRKY may play key roles in the transcriptional changes induced by waterlogging stress. Combined with weighted gene co-expression network analysis (WGCNA) analysis and K-means clustering, a total of 5 hub genes and 56 genes were identified, including F-box protein (Sin09950 and Sin12912), bZIP (Sin04465, Sin00091), WRKY (Sin01376, Sin06113), and so on. In brief, this study explored the regulatory network involved in waterlogging stress in sesame at the transcriptome level, providing valuable insights into unraveling the molecular mechanisms of waterlogging stress and facilitating the breeding of improved waterlogging-tolerant sesame varieties. Full article

This study builds on the early brain dynamics work of Erol Başar, focusing on the human electroencephalogram (EEG) in relation to the generation of event-related potentials (ERPs) and behaviour. Scalp EEG contains not only oscillations but non-wave noise elements that may not relate to functional brain activity. These require identification and removal before the true impacts of brain oscillations can be assessed. We examined EEG/ERP/behaviour linkages in young adults during an auditory equiprobable Go/No-Go task. Forty-seven university students participated while continuous EEG was recorded. Using the PaWNextra algorithm, valid estimates of pink noise (PN) and white noise (WN) were obtained from each participant’s prestimulus EEG spectra; within-participant subtraction revealed noise-free oscillation spectra. Frequency principal component analysis (f-PCA) was used to obtain noise-free frequency oscillation components. Go and No=Go ERPs were obtained from the poststimulus EEG, and separate temporal (t)-PCAs obtained their components. Exploratory multiple regression found that alpha and beta prestimulus oscillations predicted Go N2c, P3b, and SW1 ERP components related to the imperative Go response, while PN impacted No-Go N1b and N1c, facilitating early processing and identification of the No-Go stimulus. There were no direct effects of prestimulus EEG measures on behaviour, but the EEG-affected Go N2c and P3b ERPs impacted Go performance measures. These outcomes, derived via our mix of novel methodologies, encourage further research into natural frequency components in the noise-free oscillations immediately prestimulus, and how these affect task ERP components and behaviour. Full article

Background/Objectives: Synchronized beta-band oscillations (14–30 Hz) are critical for sensorimotor processing and motor performance. Modulating beta activity either locally in targeted brain regions or globally across sensorimotor networks may enhance motor function. This study aimed to explore whether transcranial direct current stimulation (tDCS) and alternating current stimulation (tACS) could enhance sensorimotor responses by modulating beta-band synchronization. Methods: Eight participants performed a stimulus–response task requiring a quick keypress to a visual cue. Response times (RTs) and electroencephalography (EEG) data were recorded during pre-, in-, and post-stimulation sessions for five conditions: motor-anodal tDCS, visual-anodal tDCS, alpha (10 Hz) tACS, beta (20 Hz) tACS, and sham, with a one-week interval between conditions. Results: Significant RT reductions were observed only after motor-anodal tDCS. EEG analysis revealed a positive correlation between these RT reductions and increased beta-phase synchronization between visual and motor areas. In contrast, tACS conditions did not yield significant RT improvements or beta-phase synchronization changes. Conclusions: These findings indicate that motor-anodal tDCS has the potential to enhance sensorimotor performance by facilitating beta-phase synchronization across the visual-motor network. The observed effects likely extend beyond localized neuronal modulation, emphasizing the importance of network-level connectivity in sensorimotor integration. Beta-phase synchronization appears to play a critical role in integrating visual and motor information, contributing to task-related performance improvements. Further research is warranted to build upon these findings and fully elucidate the underlying mechanisms. Full article

Oxidative stress-induced photoreceptor cell death is closely associated with the etiology of age-related macular degeneration (AMD), and sodium iodate (SI) has been widely used as an oxidant stimulus in AMD models to induce retinal pigment epithelium (RPE) and photoreceptor cell death. However, the mechanism underlying SI-induced photoreceptor cell death remains controversial and unclear. In this study, we elucidate that ferroptosis is a critical form of cell death induced by SI in photoreceptor-derived 661W cells. SI disrupts system Xc⁻, leading to glutathione (GSH) depletion and triggering lipid peroxidation, thereby promoting ferroptosis in photoreceptor-derived 661W cells. Additionally, SI enhances intracellular Fe²⁺ levels, which further facilitates reactive oxygen species (ROS) accumulation, making the 661W cells more susceptible to ferroptosis. Exogenous GSH, as well as specific inhibitors of ferroptosis such as Fer-1 and antioxidants like NAC, significantly attenuate SI-induced ferroptosis in photoreceptor-derived 661W cells. These findings provide new insights into the mechanisms of ferroptosis as a key pathway in SI-induced photoreceptor-derived 661W cell death. Full article

Media psychological fatigue, a common negative behavior among employees using online office applications (apps), has a significant impact on job satisfaction and performance. This study explores the influence of online office app use on job performance, differentiating between work-related and non-work-related contexts, based on the Uses and Gratifications Theory and the Stimulus–Organism–Response Theory. Data were collected from 418 employees in 11 enterprises in mainland China through random sampling. Harman’s single-factor test was utilized to evaluate common method bias. Regression analysis, bootstrap tests, and structural equation modeling (SEM) were used to analyze variable relationships and mediating effects. The results showed that work-related online office app use did not cause psychological fatigue or satisfaction, non-work-related app use enhanced job performance by improving job satisfaction, media psychological fatigue negatively affected job satisfaction and performance, psychological fatigue partially mediated the relationship between app use and job performance, and job satisfaction was essential for alleviating work-related fatigue and facilitating non-work-related use. This research emphasizes the dual influence of online office app use on employee perceptions and performance. Enterprises should focus on work-related app functions and foster a positive social environment with entertainment elements to encourage non-work-related use, reducing psychological fatigue and enhancing job satisfaction and performance. Full article