Search Results (1,682)

NiTi alloy has been widely used due to its excellent shape memory effect, superelasticity, and high damping performance. These excellent properties are mainly derived from its unique phase structure. In order to further explore the effect of different phase ratios on the performance of NiTi alloy, this study successfully prepared NiTi alloys with different atomic ratios by controlling the wire feeding speed to control the atomic ratio in the alloy. The results of TEM showed that the alloy with a lower Ni atomic ratio is enriched with Ti element, while the alloy with a higher Ni atomic ratio has a coexistence of NiTi phase and NiTi₂ phase. At the same time, the compression performance showed that the increase in Ni atomic ratio can improve the compression performance of the alloy. In addition, by constructing a molecular dynamics model of NiTi alloys with different phase ratios, the unloading recovery behavior and phase transformation characteristics of the alloy under external force were analyzed. The results showed that with the increase of the NiTi₂ phase ratio in the alloy, the irrecoverable strain also increases, exceeding the elastic strain limit of the NiTi₂ phase, resulting in the generation of disordered structure and plastic deformation in the late deformation stage. In addition, with the increase of the NiTi₂ phase ratio, the energy dissipation area of the hysteresis curve increases, reflecting a greater energy loss. Full article

The Askisi-Spelling Deficits (SD) neuropsychological web-based screener was developed to assess cognitive and spelling abilities in children, with an emphasis on the early detection of spelling disorders. This tool incorporates six tasks that evaluate cognitive domains, such as visual and auditory working memory, response inhibition, and spelling processing, providing a comprehensive framework for assessment. A study conducted with 264 Greek children, including 132 children with spelling deficits and 132 typically developing controls, aimed to implement this screening tool. Results indicated that the screener was effective, as children with spelling deficits showed significantly lower performance and longer response times across all tasks. The tool’s internal consistency was supported by split-half correlations (r = 0.64) and Spearman–Brown coefficients (r = 0.78). Nonetheless, certain limitations were identified, including the absence of latency data for specific tasks (Go/No-Go and working memory), as well as the screener’s cultural specificity, which might limit its applicability to other linguistic and orthographic systems. Future iterations should prioritize the inclusion of timing mechanisms for more detailed assessments and consider adaptations for use in languages with varying orthographic complexities. Expanding the demographic reach and conducting longitudinal validation studies would further improve its utility and generalizability. The web-based nature of the screener enables scalable and standardized administration, making it a practical and efficient tool for the early identification of spelling difficulties in children. Full article

Introduction: Pediatric cancer survivors are at high risk for visual–motor and cognitive deficits that persist throughout life. These domains are related to academic performance. The current study examined (i) whether both visuomotor and cognitive functions and (ii) whether visuomotor functions alone mediate the relationship between age and cognitive functions. Methods: In total, there were 210 participants (7–17 years): 70 posterior fossa tumors (M_age = 12.1  ±  3.2 years, 44% female) and 70 acute lymphoblastic leukemia (M_age = 12.3  ±  3.4 years, 45% female) survivors and 70 (M_age = 12.2 ± 3.3 years, 41% female) healthy controls. Visual motor integration, motor coordination and visual perception were assessed using the Beery VMI test. Working memory, attention and planning were assessed using CANTAB. Results: Impaired motor function is significantly more pronounced than cognitive impairment in both groups of cancer survivors (effect size from 25 to 30% for visual–motor and from 5 to 7% for cognitive functions). A multiple regression model revealed that age and visual motor functions are significant predictors of attention (in the ALL group β = −0.490, t = −4.88, p = 0.000) and working memory (in the PFT group β = 0.264, t = 2.72, p = 0.008; in the ALL group β = 0.215, t = 2.24, p = 0.028). Conclusions: In children who have experienced acute lymphoblastic leukemia and tumors of the posterior cranial fossa, visual–motor dysfunction is more pronounced than cognitive impairment. In addition, there is an association between visual–motor function disorders and working memory. These findings can be used to develop more specific rehabilitation protocols. Full article

Alzheimer’s disease, an irreversible neurodegenerative disorder, manifests through the progressive deterioration of memory and cognitive functions. While magnetic resonance imaging has become an indispensable neuroimaging modality for Alzheimer’s disease diagnosis and monitoring, current diagnostic paradigms predominantly rely on single-time-point data analysis, neglecting the inherent longitudinal nature of neuroimaging applications. Therefore, in this paper, we propose a multi-task feature selection algorithm for Alzheimer’s disease classification based on longitudinal imaging and hypergraphs (THM2TFS). Our methodology establishes a multi-task learning framework where feature selection at each temporal interval is treated as an individual task within each imaging modality. To address temporal dependencies, we implement group sparse regularization with two critical components: (1) a hypergraph-induced regularization term that captures high-order structural relationships among subjects through hypergraph Laplacian modeling, and (2) a fused sparse Laplacian regularization term that encodes progressive pathological changes in brain regions across time points. The selected features are subsequently integrated via multi-kernel support vector machines for final classification. We used functional magnetic resonance imaging and structural functional magnetic resonance imaging data from Alzheimer’s Disease Neuroimaging Initiative at four different time points (baseline (T1), 6th month (T2), 12th month (T3), and 24th month (T4)) to evaluate our method. The experimental results show that the accuracy rates of 96.75%, 93.45, and 83.78 for the three groups of classification tasks (AD vs. NC, MCI vs. NC and AD vs. MCI) are obtained, respectively, which indicates that the proposed method can not only capture the relevant information between longitudinal image data well, but also the classification accuracy of Alzheimer’s disease is improved, and it helps to identify the biomarkers associated with Alzheimer’s disease. Full article

Alzheimer’s disease (AD) and frontotemporal dementia (FTD) are the most common forms of dementia globally. AD is characterized by the accumulation of amyloid-β (Aβ) plaques and hyperphosphorylated tau in the brain, leading to progressive memory loss and cognitive decline, significantly impairing daily life. In contrast, FTD is marked by selective degeneration of the frontal and/or temporal lobes, typically resulting in profound changes in personality and social behavior, speech disorders, and psychiatric symptoms. Numerous studies have found microRNAs (miRNAs)—small, non-coding RNA molecules that regulate gene expression post-transcriptionally—to be dysregulated in AD and FTD. As a result, miRNAs have emerged as promising novel biomarkers for these diseases. This review examines the current understanding of miRNAs in AD and FTD, emphasizing their potential as accessible, noninvasive biomarkers for diagnosing these prevalent neurodegenerative disorders. Full article

Metabolically unhealthy obesity (MUO) is associated with increased inflammation and a higher risk of metabolic disorders compared to metabolically healthy obesity (MHO). T cell dysregulation in blood and adipose tissue may contribute to obesity-induced metabolic dysfunction, yet the characteristics of T cell subset profiles and T-cell receptor (TCR) repertoires in MHO and MUO remain unclear. We analyzed T cell subsets and TCR repertoires in peripheral blood and omental adipose tissue (oAT) from age- and BMI-matched MHO and MUO individuals using flow cytometry and high-throughput TCR sequencing. MUO individuals exhibited a higher proportion of memory CD4⁺ T cells in both compartments, with an increased frequency of central memory T cells. Circulating CD8⁺ T cells were increased in MUO, whereas CD8⁺ T cell subset composition remained unchanged in both blood and oAT. The TCR repertoire in oAT was significantly more restricted than in blood and showed greater skewing in MUO, with selective amplification of specific TRB V genes (TRBV12-4, TRBV18, TRBV7-9) and altered CDR3 length distributions. These findings suggest that distinct CD4⁺ T cell populations and specific TCR signatures may serve as potential biomarkers for metabolic dysfunction in obesity, providing insights into immune mechanisms underlying the transition from MHO to MUO. Full article

Intrinsic connectivity of the fusiform face area (FFA) was assessed using resting-state functional magnetic resonance imaging (fMRI) to compare adults with autism spectrum disorder (ASD; n = 17) and age-, sex-, and IQ-matched typically developing controls (TD; n = 22). The FFA seed region was delineated in each participant using a functional localizer task. Whole brain analyses of FFA connectivity revealed increased connectivity between the right FFA and the vermis, sensorimotor cortex, and extended face-processing network in individuals with ASD compared to TD participants; the TD group did not demonstrate increased functional connectivity. No group differences were observed from the left FFA. The relationship between FFA connectivity and the ability to remember faces significantly differed between the groups. Better face memory performance was positively correlated with increased connectivity within general visual processing areas in the ASD participants; whereas for the TD group, better face memory performance was associated with increased connectivity with brain regions related to face encoding, recognition, and retrieval. FFA overconnectivity with face, emotion, and memory processing areas, along with atypical relationships between FFA–occipito-temporal connections and face memory performance highlights a possible mechanism underlying social dysfunction in individuals with ASD. Full article

Introduction: Achieving long-term impacts from cognitive remediation (CR) interventions is a key goal in rehabilitative care. Integrating virtual reality (VR) with psychoeducational approaches within CR programs has shown promise in enhancing user engagement and addressing the complex needs of individuals with bipolar disorder (BD). A previous randomized controlled crossover feasibility trial demonstrated the viability of a fully immersive VR-CR intervention for BD, reporting low dropout rates, high acceptability, and significant cognitive improvements. This secondary analysis aimed to evaluate the stability of these outcomes over time. Methods: This paper presents a 6- to 12-month follow-up of the initial trial. Secondary cognitive outcomes were assessed, including visuospatial abilities, memory, attention, verbal fluency, and executive function, using validated assessment tools. Statistical analyses were conducted using Friedman’s test. Results: A total of 36 participants completed the 6- to 12-month follow-up. Overall, cognitive functions showed a trend toward stability or improvement over time, except for visuospatial and executive functions, which demonstrated inconsistent trajectories. Significant improvements were observed in language (p = 0.02). Conclusion: This study highlights the overall stability of cognitive functions 12 months after a fully immersive VR-CR program for individuals with BD. To sustain long-term clinical benefits, an integrated approach, such as incorporating psychoeducational strategies within cognitive remediation interventions, may be essential. Further follow-up studies with control groups and larger sample sizes are needed to validate these findings. Full article

Background/Objectives: The purpose of this research was to investigate the effects of bisphenol A (BPA) exposure on neurobehavioral testing in young Wistar rats and to evaluate the therapeutic potential of Thymus ciliatus (TEO) essential oil to attenuate the damage induced by this chemical toxin. Methods: The essential oil was extracted by hydro-distillation (yield of 2.26%), and the characterization by GC-MS indicates that the major components of Thymus ciliatus oil are thymol (63.33%), p-cymene (13.4%), and σ-terpinene (6.69%). Acute BPA intoxication was induced with a dose of 50 mg/kg orally for 60 days. The neurobehavioral evaluation, performed using a comprehensive set of tests including the forced swim test, dark/light box, Morris water maze, open field test, and sucrose preference test, clearly demonstrated that bisphenol A (BPA) exposure induced significant neurobehavioral impairments. Results: These impairments included reduced exploratory behavior indicative of heightened stress, anxiety, and depressive-like states, as well as deficits in memory and learning. Furthermore, BPA intoxication was associated with metabolic disturbances such as hyperglycemia along with histopathological evidence of brain tissue damage. However, TEO treatment attenuated these adverse effects by restoring neurobehavioral function. Molecular docking analysis revealed an affinity between the major essential oils identified in T. ciliatus, BPA, and the 5HT2C receptor and the MAO, AChE, and BChE enzymes, suggesting a potential mechanism underlying BPA’s effects on behavior and memory. In addition, TEO also showed an interaction with these molecules, suggesting a therapeutic potential against BPA. These findings underscore the promising role of TEO in mitigating the poisonous effects of BPA and pave the way for additional research into the molecular mechanisms and therapeutic uses of natural bioactive compounds for the prevention and treatment of toxic diseases. Thymol, the major compound in TEO, exhibited activity related to the dopamine and serotonin pathways, so it could have potential antidepressant properties. Conclusions: Thymol might be a promising candidate for the treatment of neurodegenerative and neurological disorders such as depression, Parkinson’s disease, and Alzheimer’s disease while also preventing histological damage in the brain. Full article

Episodic memory training plays a crucial role in cognitive enhancement, particularly in addressing age-related memory decline and cognitive disorders. Accurately assessing the effectiveness of such training requires reliable methods to capture changes in memory function. Electroencephalography (EEG) offers an objective way of evaluating neural activity before and after training. However, EEG classification in episodic memory assessment remains challenging due to the variability in brain responses, individual differences, and the complex temporal–spatial dynamics of neural signals. Traditional EEG classification methods, such as Support Vector Machines (SVMs) and Convolutional Neural Networks (CNNs), face limitations when applied to episodic memory training assessment, struggling to extract meaningful features and handle the inherent uncertainty in EEG signals. To address these issues, this paper introduces DU-former, which improves feature extraction and enhances the model’s robustness against noise. Specifically, data uncertainty (DU) explicitly handles data uncertainty by modeling input features as Gaussian distributions within the reparameterization module. One branch predicts the mean through convolution and normalization, while the other estimates the variance via average pooling and normalization. These values are then used for Gaussian reparameterization, enabling the model to learn more robust feature representations. This approach allows the model to remain stable when dealing with complex or noisy data. To validate the method, an episodic memory training experiment was designed with 17 participants who underwent 28 days of training. Behavioral data showed a significant reduction in task completion time. Object recognition accuracy also improved, as indicated by the higher proportion of correctly identified target items in the episodic memory testing game. Furthermore, EEG data collected before and after the training were used to evaluate the DU-former’s performance, demonstrating significant improvements in classification accuracy. This paper contributes by introducing uncertainty learning and proposing a more efficient and robust method for EEG signal classification, demonstrating superior performance in episodic memory assessment. Full article

Alzheimer’s disease (AD) is a complex neurodegenerative disorder characterized by progressive cognitive decline, memory loss, and behavioral changes. It poses a significant global health challenge. AD is associated with the accumulation of amyloid-β (Aβ) plaques and neurofibrillary tangles (NFTs) in the brain, along with chronic inflammation, dysfunctional neurons, and synapse loss. While the prevalence of AD continues to rise, the current FDA-approved drugs offer only limited effectiveness. Emerging evidence suggests that obesity, insulin resistance (IR), and type 2 diabetes mellitus (T2DM) are also implicated in AD pathogenesis, with epidemiological studies and animal models confirming the impact of IR on Aβ accumulation, and high-fat diets also exacerbating Aβ accumulation. Since neuroinflammation activated by Aβ involves the nuclear factor kappa-light-chain-enhancer of the activated B cell (NF-κB) pathway, the inhibition of NF-κB and NLRP3 inflammasome activation are potential therapeutic strategies in AD. Bioactive compounds, including polyphenols (resveratrol, epigallocatechin-3-gallate, curcumin, and quercetin), and omega-3 polyunsaturated fatty acids, show promising results in animal studies and clinical trials for reducing Aβ levels, improving cognition and modulating the signaling pathways implicated in AD. This review explores the interplay between obesity, IR, inflammation, and AD pathology, emphasizing the potential of dietary compounds and their role in reducing inflammation, oxidative stress, and cognitive decline, as viable strategies for AD prevention and treatment. By integrating epidemiological findings, observational studies, and clinical trials, this review aims to provide a comprehensive understating of how metabolic dysfunctions and bioactive compounds influence AD progression. Full article

Hydrogen sulfide (H₂S) has emerged as a pivotal gaseous transmitter in the central nervous system, influencing synaptic plasticity, learning, and memory by modulating various molecular pathways. This review examines recent evidence regarding how H₂S regulates NMDA receptor function and neurotransmitter release in neuronal circuits. By synthesizing findings from animal and cellular models, we investigate the impacts of enzymatic H₂S production and exogenous H₂S on excitatory synaptic currents, long-term potentiation, and intracellular calcium signaling. Data suggest that H₂S interacts directly with NMDA receptor subunits, altering receptor function and modulating neuronal excitability. Simultaneously, H₂S promotes the release of neurotransmitters such as glutamate and GABA, shaping synaptic dynamics and plasticity. Furthermore, reports indicate that disruptions in H₂S metabolism contribute to cognitive impairments and neurodegenerative disorders, underscoring the potential therapeutic value of targeting H₂S-mediated pathways. Although the precise mechanisms of H₂S-induced changes in synaptic strength remain elusive, a growing body of evidence positions H₂S as a significant regulator of memory formation processes. This review calls for more rigorous exploration into the molecular underpinnings of H₂S in synaptic plasticity, paving the way for novel pharmacological interventions in cognitive dysfunction. Full article

Background and purpose: This study aimed to investigate risk factors, prodromal signs, and non-motor symptoms (NMSs) across various motor subtypes of Parkinson’s disease (PD) and to interpret the findings within the context of existing hypotheses on PD subtypes. Methods: A search of the database yielded 300 individuals who satisfied the study’s inclusion and exclusion criteria. Among them, 168 patients diagnosed with idiopathic PD underwent a comprehensive evaluation of both motor and non-motor symptoms. The classification of motor subtypes was conducted according to the methodology proposed by Stebbins. Results: The study population consisted of 59.9% males, with an average age of disease onset at 65.45 years. Among them, 87 (51.8%) were classified as having the tremor-dominant (TD) subtype, 61 (36.3%) had the postural instability and gait disorder (PIGD) subtype, and 20 (11.9%) fell into the intermediate (I) subtype. Significant differences between motor subtypes were observed in age at assessment (p = 0.03), age at onset (p = 0.02), education level (p = 0.015), handedness (p = 0.013), proportion of non-smokers (p = 0.021), cognitive impairment (p = 0.003), and apathy (p = 0.003). Additionally, statistically significant variations were found across different rating scales and questionnaires, including MoCA (p = 0.009), HAM-A (p = 0.008), HAM-D (p = 0.007), H&Y (p = 0.004), SAS (p = 0.004), NMSS Domain 3 (mood/apathy) (p = 0.003), and NMSS Domain 5 (attention/memory) (p = 0.003). Conclusions: The study revealed substantial differences between motor subtypes, underscoring the complexity of PD. These findings highlight the importance of comprehensive evaluations of both MS and NMSs to optimize patient care, improve quality of life, and fit well within the framework of the existing hypotheses of PD subtypes. Full article

As a common neurodegenerative disorder, Alzheimer’s disease (AD) manifests as progressive memory loss, cognitive deficits, and dementia in older adults. As the basis of the traditional Chinese medicinal herb Goji berries, Lycium barbarum polysaccharide (LBP) has been proven to exhibit multiple pharmacological activities, including antioxidant, neuroprotective, and anti-inflammatory effects. Evidence supports that LBP can enhance cognitive function and holds promise in counteracting AD. In order to determine the neuroprotective effects of LBP, this study was conducted on an AD rat model induced by intracerebroventricular injection of Aβ_1–42 peptides. From 24 h after induction until the end of the behavioral experiment, rats were orally administered LBP (150 and 300 mg/kg) once a day. Neurobehavioral parameters were evaluated starting 1 week after administration. After behavioral tests, rats were euthanized, and the whole brain and cortex were isolated to detect the variations in histopathology and biochemical parameters. LBP significantly reversed cognitive impairments, assessed through the Y-maze, Passive Avoidance Test (PAT), and Morris water maze (MWM) test, respectively. Furthermore, LBP not only attenuated NFκB, TNF-α, IL-1β, IL-6, AChE, and oxidative/nitrosative stress levels but also increased IL-4, IL-10, and ACh levels and ChAT activity in the cortex. HE staining also exhibited the neuroprotection of LBP. Our study findings imply that LBP may improve cognitive function through multiple mechanisms and is a potential anti-AD compound. Full article

Objective: We aimed to compare executive functions (EF), anxiety, social participation, and quality of life (QoL) between children with migraine and healthy controls during the COVID-19 pandemic, and to examine these parameters in children in each group who did vs. did not contract COVID-19. Materials and Methods: A prospective cohort study was carried out. The patient group comprised children seen in our pediatric neurology clinic for migraine, and the control group was composed of aged-matched healthy children with no neurological findings or developmental disorders. The participants’ parents completed a health and demographic questionnaire, the BRIEF (child/adolescent version), the PedsQL, the State–Trait Anxiety Inventory for Children (STAIC), and the CASP. The participants or their parents furnished information on whether the participant had contracted COVID-19. Results: A total of 84 children and adolescents aged 6–17.5 (mean of 12.8) participated in the study, including 33 with migraine (17 boys, 16 girls) and 51 healthy controls (28 boys, 23 girls). The children with migraine showed significantly lower EF due to reduced behavioral regulation, higher trait anxiety, and lower physical, emotional, and school-related QoL. Reduced EF correlated with the intensity of migraine attacks, higher anxiety, reduced social participation, and reduced QoL. Lower social participation correlated with reduced QoL and predicted emotional and social QoL. The BRIEF metacognition scale predicted school-related QoL. Healthy children who contracted COVID-19 showed significantly lower EF than children with migraine in the inhibition (56.66 ± 10.56 vs. 45.71 ± 7.12, p = 0.013) and initiation (60.01 ± 11.89 vs. 46.01 ± 6.54, p = 0.005) BRIEF scales, and in the general metacognition index (65.83 ± 14.48 vs. 46.75 ± 9.19, p = 0.003). Healthy children who contracted COVID-19 had significantly worse initiation and working memory compared to those who did not contract COVID-19 (initiation: 60.01 ± 11.89 vs. 46.81 ± 8.89, p = 0.007), working memory: 61.16 ± 15.48 vs. 47.21 ± 11.06, p = 0.021). Conclusion: Migraine has a significant negative impact on executive functions in children and adolescents, greater than contracting COVID-19. Executive dysfunction influences patients’ emotional state, participation in social activities, and quality of life. The COVID-19 pandemic had a less deleterious effect on migraine patients compared to the healthy control group. Further research on pediatric migraine is warranted. Full article