Search Results (621)

Zinc (Zn²⁺) is a trace element essential for its catalytic, antioxidant, and immunomodulatory roles extending to synaptic signalling in the central nervous system. In this narrative review, we aim to offer the reader evidence linking perturbations of the Zn²⁺ homeostasis, including deficiency, excess, or transportation anomalies, to neuropsychiatric conditions such as Alzheimer’s disease (AD), Parkinson’s disease (PD), autism spectrum disorder (ASD), attention deficit hyperactivity disorder (ADHD), schizophrenia (SCZ), major depressive disorder (MDD), and bipolar disorder (BD). A targeted, unsystematic PubMed search followed by an extensive pearl-growing strategy was applied to further augment study selection based on the extensive expertise of study authors. Overall, most of the evidence currently available suggests a modest benefit for a Zn²⁺ supplement of around 25–30 mg/day as an augmentation to MDD treatment, with potential benefits of smaller magnitude in paediatric ADHD. Evidence for perturbations of Zn²⁺ as a biomarker of risk for these neuropsychiatric disorders remains unconvincing. The role of Zn²⁺ supplements in the treatment of the selected conditions remains largely unknown due to the lack of specific, randomised controlled trials conducted to explore their efficacy. The long-term safety, optimal doses for specific applications, and the exploration of possible biomarkers to stratify patient selection to identify the optimal candidate for Zn²⁺ supplements remain unanswered questions. Full article

As the primary discharge channel for fault currents, substation grounding grids are crucial for ensuring the safe and stable operation of power systems. Due to its non-destructive and efficient nature, the pulsed eddy current (PEC) method has become a research hotspot in grounding grid detection in recent years. However, during the detection process, the signal is severely interfered with by substation noise, seriously affecting data quality and interpretation accuracy. To address the problem of suppressing both power frequency and random noise, this paper proposes a composite denoising method that combines bipolar cancellation, minimum noise fraction (MNF), and mask-guided self-supervised denoising. First, based on the periodic characteristics of power frequency noise, a bipolar pulse excitation and differential averaging process is designed to effectively filter out power frequency interference. Subsequently, an MNF algorithm is introduced to identify and reconstruct random noise, improving signal purity. Furthermore, a mask-guided self-supervised denoising model is constructed, using a segmentation convolutional neural network to extract signal-noise masks from noisy data, achieving refined suppression of residual noise. Comparative experiments with simulation and actual substation noise data show that the proposed method outperforms existing typical noise reduction algorithms in terms of signal-to-noise ratio improvement and waveform fidelity, significantly improving the availability and interpretation reliability of pulsed eddy current data. Full article

In radio frequency (RF) systems, the mixer is a critical component for achieving frequency conversion in electromagnetic sensor backends. This paper proposes a mixer design methodology aimed at improving noise figure and conversion gain specifically for sensor signal processing applications. This design employs a process incorporating high-quality bipolar junction transistors (BJTs) and adopts a mixer-first architecture instead of a conventional low noise amplifier (LNA). By optimizing the layout and symmetry of the BJTs, the input impedance can be flexibly adjusted, thereby simplifying the receiver front-end while simultaneously improving local oscillator (LO) feedthrough. Design and simulation were completed using Advanced Design System (ADS) 2020 software. Simulation results demonstrate that the proposed mixer exhibits significant advantages in suppressing noise and interference while enhancing conversion gain, making it particularly suitable for electromagnetic sensor backend applications. Full article

The reliability and lifetime of insulated gate bipolar transistors (IGBTs) are critical to ensuring the stability and safety of power electronic systems. IGBTs are widely used in electric vehicles, renewable energy systems, and industrial automation. However, their degradation over time poses a significant risk to system performance. Therefore, this paper proposes a data-driven approach based on a Long Short-Term Memory (LSTM) network optimized by a Genetic Algorithm (GA) to predict IGBT degradation. The study examines the health monitoring of insulated gate bipolar transistors from a device physics perspective. Degradation mechanisms that alter parasitics and electro-thermal stress produce characteristic changes in the turn-off overvoltage and the on-state voltage. Using power-cycling data from packaged half-bridge modules, an LSTM-based sequence model configured by a genetic algorithm search reduces error against an identically trained baseline (RMSE = 0.0073, MAE = 0.057, MAPE = 0.726%) under the shared protocol, with the clearest advantages in the early stage of degradation. These results support predictive maintenance and health management in power-electronic systems. Full article

With the rapid advance of digital technologies, the service industry has become a key driver of sustainable economic growth and the restructuring of international trade. Drawing on value-added trade flows for five pivotal service industries—construction, air transportation, postal telecommunications, financial intermediation, and education—over 2013–2021, this study examines the spatial evolution of the global service value chain (GSVC). Using social network analysis combined with a Temporal Exponential Random Graph Model (TERGM), we assess the dynamics of the GSVC’ core–periphery structure and identify heterogeneous determinants shaping their spatial networks. The findings are as follows: (1) Exports across the five industries display an “East rising, West declining” pattern, with markedly heterogeneous magnitudes of change. (2) The construction industry is Europe-centered; air transportation exhibits a U.S.–China bipolar structure; postal telecommunications show the most pronounced “East rising, West declining” shift, forming four poles (United States, United Kingdom, Germany, China); financial intermediation contracts to a five-pole core (China, United States, United Kingdom, Switzerland, Germany); and education becomes increasingly multipolar. (3) The GSVC core–periphery system undergoes substantial reconfiguration, with some peripheral economies moving toward the core; the core expands in air transportation, while postal telecommunications exhibit strong regionalization. (4) Digital technology, foreign direct investment, and manufacturing structure promote network evolution, whereas income similarity may dampen it; the effects of economic freedom and labor-force size on spatial network restructuring differ significantly by industry. These results underscore the complex interplay of structural, institutional, and geographic drivers in reshaping GSVC networks and carry implications for fostering sustainable services trade, enhancing interregional connectivity, narrowing global development gaps, and advancing an inclusive digital transformation. Full article

Background/Objectives: Gastric cancer often presents at advanced stages with complications such as iron-deficiency anemia (IDA) due to chronic bleeding, representing a significant global health burden. Palliative management of bleeding tumors in frail patients remains challenging. This study evaluates the feasibility, safety, and efficacy of endoscopic calcium-electroporation (Ca-EP), a novel non-thermal ablation technique, for controlling bleeding in end-stage gastric cancer. Methods: Retrospective case series including consecutive patients with end-stage, bleeding gastric cancer and IDA requiring transfusions. Ca-EP was performed using the EndoVE system, which delivers bipolar electrical pulses (250 kHz) to induce reversible electroporation, enabling calcium influx and tumor cell apoptosis. Primary endpoints were clinical success (hemoglobin stabilization/reduced transfusions) and safety. Secondary endpoints included tumor regression, procedural time, and hospital stay. Results: Five patients (median age 81 years) were included. Clinical success was achieved in 80% (4/5) of patients, with reduced transfusion needs and stable hemoglobin levels. One patient required adjunctive hemostatic radiotherapy. No major or minor adverse events were reported, and all patients were discharged within 24 h. Procedural median time was 38 min (range: 22–65). Endoscopic follow-up in three patients showed mild tumor regression or stability. Three patients required repeat Ca-EP sessions due to recurrent bleeding. Conclusions: Endoscopic Ca-EP is a safe, minimally invasive palliative option for bleeding gastric cancer, offering sustained hemostasis and potential antitumor effects without systemic toxicity. Its feasibility in frail patients underscores its clinical relevance, though larger prospective studies are needed to optimize parameters and validate long-term outcomes. Full article

This study evaluated the performance of a constant-current two-compartment bipolar membrane electrodialysis (BMED) system comprising cation exchange membranes and bipolar membranes for the recovery of sodium hydroxide (NaOH) from sodium sulfate (Na₂SO₄) solution. Key operating parameters, current density, feed concentration, initial base concentration, and solution volume, were systematically varied to investigate their effects on ion transport, NaOH concentration, current efficiency, and energy consumption. At 450 A/m² with 1.30 M Na₂SO₄, 0.10 M initial NaOH, and 1.00 L solution volume, the system achieved a NaOH recovery yield of 69.21%, a final concentration of 2.13 M, a current efficiency of 36.39%, and an energy consumption of 1.82 kWh/kg Na₂SO₄ processed, corresponding to 4.72 kWh/kg NaOH produced, indicating optimal energy efficiency and process stability. To maximize concentration, the highest NaOH concentration of 2.85 M was obtained at the same current density by reducing the initial NaOH volume to 0.50 L, although this led to increased water transport and higher energy consumption (2.31 kWh/kg Na₂SO₄; 5.99 kWh/kg NaOH), compromising process efficiency. Full article

Over the past two decades, immune–inflammatory dysregulation has emerged as a central paradigm in the biology of mood disorders. Patients with major depression (MDD) and bipolar disorder (BD) frequently display low-grade systemic inflammation. Elevated C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) identify clinically relevant subgroups of patients characterized by greater severity, cognitive impairment, and poor treatment response. Changes in the gut microbiota and disruptions of the blood–brain barrier (BBB) act as important gateways through which systemic immune activity can influence the brain. At the intracellular level, pattern-recognition receptors activate convergent hubs including NF-κB, JAK/STAT, and MAPK cascades, while the NLRP3 inflammasome integrates mitochondrial dysfunction and oxidative stress with IL-1β release and pyroptosis. These pathways converge on glial dysregulation, impaired BDNF/TrkB signaling, and kynurenine pathway (KP) alterations, fostering excitotoxicity and synaptic deficits. Translational studies demonstrate that elevated CRP and IL-6 predict poor antidepressant outcomes. Anti-inflammatory agents such as infliximab and celecoxib show efficacy in specific subgroups of patients. Emerging multi-omics approaches identify immuno-metabolic biotypes, supporting the rationale for biomarker-guided stratification. These findings define an ‘inflammatory biotype’ of mood disorders and highlight the need for biomarkers and precision-based trials to guide treatment. Full article

Hybrid cascaded multi-terminal HVDC systems represent a significant advancement in HVDC transmission technology. A notable real-world implementation of this concept is the bipolar hybrid cascaded multi-terminal high voltage direct current (MTDC) project in China, which successfully transmits hydropower from Baihetan to Jiangsu. This system combines MMCs for system support with LCCs for high-power transmission, offering both flexibility and efficiency in long-distance power delivery. This research explores the characteristics of main DC fault types in such systems, classifying faults based on sections and modes while analyzing their unique outcomes depending on DC fault locations. By focusing on the DC-side terminal behavior of the MMCs and LCCs, the main response processes to asymmetrical DC faults are investigated in detail. This study offers a detailed analysis of asymmetrical DC faults in bipolar HVDC systems, proposing a new classification based on fault characteristics such as current, voltage, active power, and reactive power. A supporting theoretical analysis is also presented. It identifies specific control demands needed for effective fault mitigation. PSCAD/EMTDC simulation results demonstrate that DC faults with similar characteristics can be consistently grouped into distinct categories by this new classification method. Each category is further linked to specific control demands, providing a strong basis for developing advanced protection strategies and practical solutions that enhance the stability and reliability of hybrid cascaded HVDC systems. Full article

Soil electrical conductivity (EC) and water content are key indicators of soil health, influencing nutrient availability, salinity stress, and crop productivity. Monitoring these parameters is critical for precision agriculture. However, most existing measurement systems are costly, which restricts their use in practical field conditions. The aim of this study was to develop and validate a low-cost, portable system for simultaneous measurement of soil EC, water content, and temperature, while maintaining accuracy comparable to laboratory-grade instruments. The system was designed with four electrodes arranged in two pairs and employed an AC bipolar pulse method with a constant-current circuit, precision rectifier, and peak detector to minimize electrode polarization. Experiments were carried out in sandy loam soil at water contents of 13%, 18%, and 22% and KNO₃ concentrations of 0, 0.1, 0.2, and 0.4 M. Measurements from the developed system were benchmarked against a professional impedance analyzer (E4990A). The findings demonstrated that EC increased with both frequency and water content. At 100 Hz, the mean error compared with the analyzer was 8.95%, rising slightly to 9.98% at 10 kHz. A strong linear relationship was observed between EC and KNO₃ concentration at 100 Hz (R² = 0.9898), and for the same salt concentration (0.1 M KNO₃) at 100 Hz, EC increased from ~0.26 mS/cm at 13% water content to ~0.43 mS/cm at 22%. In conclusion, the developed system consistently achieved <10% error while maintaining a cost of ~€55, significantly lower than commercial devices. These results confirm its potential as an affordable and reliable tool for soil salinity and water content monitoring in precision agriculture. Full article

γ-aminobutyric acid (GABA), the primary inhibitory neurotransmitter in the central nervous system (CNS), regulates neuronal excitability, synaptic plasticity, and oscillatory activity essential for cognition, emotion, and behavior. Disruptions in GABAergic signaling are increasingly recognized as key contributors to a range of neurodevelopmental disorders (NDDs), including schizophrenia (SZ), autism spectrum disorder (ASD), major depressive disorder (MDD), bipolar disorder (BD), and intellectual disability (ID). In this review, we analyze the data available from the literature concerning the components of the GABA pathway. We describe the main steps of GABA metabolism, including GABA synthesis and release, GABA receptors neurotransmission, GABA reuptake and catabolism, and evaluate their involvement in the pathogenesis of neurodevelopmental disorders. We suggest the possibility of existence of so far undescribed mechanisms which maintain the concentrations of GABA at a relatively physiological level when the function of glutamic acid decarboxylases is compromised by mutations. Searching for these mechanisms could be important for better understanding neurodevelopment and could give a clue for future searches for new therapeutic approaches for treating or alleviating the symptoms of BD and SZ. We also argue that the metabolic stage of the GABA pathway has only a minor direct effect on GABA signaling and rather causes clinical effects due to accumulation of neurotoxic byproducts. Full article

Background: Suicide attempts often co-occur with bipolar disorder (BD), major depressive disorder (MDD), and schizophrenia (SCH). Although impairments of the serotonin (5-HT) system have been associated with suicide attempts, it remains unclear whether these alterations reflect suicidal behavior or are confounded by underlying psychiatric diagnosis. This study used a genotype-informed dynamic model of the 5-HT presynapse to disentangle the effects of suicide attempts and psychiatric diagnosis. Methods: We applied a personalized dynamic model of the 5-HT presynapse to 392 psychiatric patients (with BD, MDD, or SCH), categorized by suicide attempt status, and 140 unaffected individuals. The model incorporated five variants across TPH2, SLC6A4, and MAOA genes simulating individual-specific concentration changes of five 5-HT-related molecular species. Model outputs were summarized by six statistical measures (mean, median, maximum, standard deviation, skewness, and kurtosis) and compared across groups. Results: No significant differences were found across groups defined by suicide attempt status and unaffected individuals. However, diagnosis significantly influenced 5-hydroxyindoleacetic acid (5-HIAA) mean, median, maximum, and standard deviation (all p < 0.05). BD patients had lower 5-HIAA levels than SCH patients (mean: p = 0.013; median: p = 0.013; maximum: p = 0.014; standard deviation: p = 0.014). MDD patients also showed lower 5-HIAA levels than SCH patients for the same measures, with differences approaching significance. No significant difference was observed between BD and MDD patients. A diagnosis-by-suicide attempt status interaction was observed for 5-HIAA skewness (p = 0.013). Conclusions: Model-derived 5-HT profiles were shaped primarily by diagnosis, while temporal dynamics of 5-HIAA, rather than its absolute levels, was associated with suicide attempt status. Thus, personalized dynamic modeling incorporating genetic variants may aid in detecting subtle molecular signatures across diagnoses and suicidal behavior. Full article

Background/Objectives: Emerging evidence suggests a role for oral microbiota in mood disorders, particularly bipolar disorder (BD), complementing established links between gut dysbiosis and psychiatric symptoms. This study investigates the composition of oral microbial taxa and the expression of inflammation-related pri-miRNAs (146a and 155) in individuals with BD, aiming to explore their potential as biomarkers in the oral–gut–brain axis. Methods: A matched case–control design was implemented, recruiting 25 BD patients and 46 controls matched by age and sex. Salivary samples were collected, and microbial profiling was conducted via real-time qPCR targeting major bacterial phyla and genera. Pri-miRNA 146a and 155 expression was evaluated through RT-qPCR using validated primers. Statistical comparisons between groups were performed using Fisher’s exact test and non-parametric tests for continuous variables. Results: Microbial analysis revealed significant reductions (p < 0.01) in α-Proteobacteria, γ-Proteobacteria, and Actinobacteria in BD patients versus controls. A shift toward a higher Firmicutes/Bacteroidetes ratio was observed in the BD cohort, suggesting differences in the oral biotic status between the two groups. However, pri-miRNA 146a and 155 expression levels did not differ significantly between the groups and exhibited high inter-individual variability. Conclusions: The findings indicate that oral microbiota composition differs in BD patients, potentially influencing systemic homeostasis through interactions with gut microbial communities and SCFA pathways. These findings should be interpreted as preliminary and hypothesis-generating given the modest sample size. While pri-miRNAs 146a and 155 did not distinguish BD status, the observed microbial taxa alterations should be regarded as exploratory and hypothesis-generating. Larger, longitudinal studies are required to clarify their potential role in BD pathogenesis and risk assessment. Full article

Background/Objectives: Schizophrenia (SCH), bipolar disorder (BPD), and major depressive disorder (MDD) are increasingly viewed as neuroimmune disorders shaped by viral exposure and inflammation. Disorder-specific immunovirological profiles, however, remain poorly defined. Methods: In this cross-sectional study, we assessed Epstein–Barr Virus (EBV) and Herpes Simplex Virus type 1 (HSV-1) seropositivity and measured serum CRP, IL-6, and IL-1β in 708 participants: 110 with SCH, 121 with BPD, 135 with MDD, and 342 healthy controls (HC). Statistical analyses included Shapiro–Wilk tests for normality; Kruskal–Wallis with Bonferroni-adjusted Dunn post hoc comparisons; and logistic regression adjusted for age, sex, and marital status. Results: EBV seropositivity was higher in SCH (90.9%) than in HC (78.9%) (OR = 3.46, 95% CI: 1.68–7.12; p = 0.001) but not in BPD or MDD. HSV-1 seropositivity was elevated in BPD (83.5%) versus HC (67.0%) (OR = 2.29, 95% CI: 1.34–3.92; p = 0.003), with no differences in SCH or MDD. Inflammatory biomarkers were significantly increased in SCH and MDD compared to HC (p < 0.001), while BPD showed no differences. Conclusions: The findings delineate distinct immunovirological patterns across major psychiatric disorders. Schizophrenia was characterized by EBV seropositivity accompanied by systemic inflammatory activation, bipolar disorder by HSV-1 seropositivity in the absence of inflammatory changes, and major depressive disorder by inflammatory dysregulation independent of viral exposure. These disorder-specific profiles highlight heterogeneity in neuroimmune pathways and underscore the potential relevance of biomarker-based stratification for generating hypotheses regarding targeted antiviral or anti-inflammatory interventions in psychiatric populations. Full article

The recycling of spent lithium-ion batteries generates Na₂SO₄-containing wastewater, resulting in environmental problems and resource losses. This study investigates a treatment method employing bipolar membrane electrodialysis (BMED) to recover H₂SO₄ and NaOH from such wastewater. The acid and base recovery efficiencies, energy consumption, operational stability, and economic feasibility of two BMED configurations, i.e., two- and three-compartment systems, were systematically compared. The current density, initial concentrations of the feed, and initial concentrations and volumes of the acid and base were optimized under constant current conditions. The three-compartment system exhibited higher acid purity and stability, whereas the other system exhibited lower energy consumption and membrane degradation. Under optimal conditions, both systems successfully recovered H₂SO₄ and NaOH from the Na₂SO₄-containing wastewater. A techno-economic analysis based on a lab-scale process revealed that the two-compartment system exhibited cost effectiveness while the three-compartment system showed long-term operational stability. These findings suggest that BMED is a viable and effective solution for the treatment of Na₂SO₄-containing wastewater generated from battery recycling processes. Full article