Search Results (362)

Background: Lower phylogenetic species are known to rebuild cut-off caudal parts with regeneration of the central nervous system (CNS). In contrast, CNS regeneration in higher vertebrates is often attributed to immaturity, although this has never been conclusively demonstrated. The emergence of stem cells and their effective medical applications has intensified research into spinal cord regeneration. However, despite these advances, the impact of clinical trials involving spinal cord-injured (SCI) patients remains disappointingly low. Long-distance regeneration has yet to be proven. Methods: Our study involved a microsurgical dorsal myelotomy in fetal rats. The development of pioneering long primary afferent axons during early gestation was examined long after birth. Results: A single cut triggered the intrinsic ability of the dorsal root ganglion (DRG) neurons to reprogram. Susceptibility to hypoxia caused the axons to stop developing. However, the residual axonal outgrowth sheds light on the intriguing temporal and spatial events that reveal long-distance CNS regeneration. The altered phenotypes displayed axons of varying lengths and different features, which remained visible throughout life. The previously designed developmental blueprint was crucial for interpreting these enigmatic features. Conclusions: This research into immaturity enabled the exploration of the previously impenetrable domain of early life and the identification of a potential missing link in CNS regeneration research. Central axon regeneration appeared to occur much faster than is generally believed. The paradigm provides a challenging approach for exhaustive intrauterine reprogramming. When the results demonstrate pre-clinical effectiveness in CNS regeneration research, the transformational impact may ultimately lead to improved outcomes for patients with spinal cord injuries. Full article

In the modern era, the use of blockchain technology has been growing rapidly, where Ethereum smart contracts play an important role in securing decentralized application systems. However, these smart contracts are also susceptible to a large number of vulnerabilities, which pose significant threats to intelligent systems and IoT applications, leading to data breaches and financial losses. Traditional detection techniques, such as manual analysis and static automated tools, suffer from high false positives and undetected security vulnerabilities. To address these problems, this paper proposes an Artificial Intelligence (AI)-based security framework that integrates Generative Adversarial Network (GAN)-based feature selection and deep learning techniques to classify and detect malware attacks on smart contract execution in the blockchain decentralized network. After an exhaustive pre-processing phase yielding a dataset of 40,000 malware and benign samples, the proposed model is evaluated and compared with related studies on the basis of a number of performance metrics including training accuracy, training loss, and classification metrics (accuracy, precision, recall, and F1-score). Our combined approach achieved a remarkable accuracy of 97.6%, demonstrating its effectiveness in detecting malware and protecting blockchain systems. Full article

Evaporative cooling (EC) offers an energy-efficient alternative to direct expansion (DX) cooling but suffers from high water consumption. This limitation can be mitigated by pre-cooling incoming fresh air using cooler exhaust air via energy recovery. This study presents and optimizes a solar-driven EC system integrated with underfloor air distribution (UFAD) to enhance thermal comfort and minimize water use in a temporary office in Riyadh’s arid climate. A 3D CFD model was developed and validated against published data to simulate indoor airflow, providing data for thermal comfort evaluation using the predicted mean vote model in cases with and without energy recovery. A year-round hourly energy analysis revealed that the solar-driven EC-UFAD system reduces grid power consumption by 93.5% compared to DX-based UFAD under identical conditions. Energy recovery further cuts annual EC water usage by up to 31.3%. Operational costs decreased by 84% without recovery and 87% with recovery versus DX-UFAD. Full article

The gut microbiota and its interaction with the nervous system through the gut–brain axis (MGB) have been the subject of growing interest in biomedical research. It has been proposed that modulation of microbiota using probiotics could offer a promising therapeutic alternative for mood regulation and the treatment of anxiety and depression disorders. The findings indicate that several probiotic strains, such as Lactobacillus and Bifidobacterium, have demonstrated anxiolytic and antidepressant effects in pre and clinical studies. These effects seem to be mediated by the regulation of the hypothalamic–pituitary–adrenal axis (HPA), the synthesis of neurotransmitters such as serotonin (5-HT) and Gamma-amino-butyric acid (GABA), as well as the modulation of systemic inflammation. However, the lack of standardization in dosing and strain selection, in addition to the scarcity of large-scale clinical studies, limit the applicability of these findings in clinical therapy. Additional research is required to establish standardized therapeutic protocols and better understand the role of probiotics in mental health. The aim of this narrative review is to discuss the relationship between the gut microbiota and the MGB axis in the context of anxiety and depression disorders, the underlying neurobiological mechanisms, as well as the preclinical evidence for the effect of probiotics in modulating these disorders. In this way, an exhaustive search was carried out in scientific databases including PubMed, ScienceDirect, Scopus, and Web of Science. Preclinical research evaluating the effects of different probiotic strains in animal models during chronic treatment was selected, excluding those studies that did not provide access to the full text. Full article

According to the World Health Organization (WHO), a healthy lifestyle is defined as a way of living that lowers the risk of becoming seriously ill or dying prematurely. Physical activity, as a well-known contributor to overall health, plays a vital role in supporting such a lifestyle. Exercise induces complex molecular responses that mediate both acute metabolic stress and long-term physiological adaptations. FGF21 (fibroblast growth factor 21) and GDF15 (growth differentiation factor 15) are recognized as metabolic stress markers, while their receptors play critical roles in cellular signaling. However, the differential gene expression patterns of these molecules in trained and untrained individuals following exhaustive exercise remain poorly understood. This study aimed to examine the transcriptional and protein-level responses in trained and untrained individuals performed a treadmill maximal exercise test to voluntary exhaustion. Blood samples were collected at six time points (pre-exercise, immediately post-exercise, and 0.5 h, 6 h, 24 h, and 48 h post-exercise). Gene expression of FGF21, GDF15, FGFR1 (fibroblast growth factor receptors), FGFR3, FGFR4, KLB (β-klotho), and GFRAL (glial cell line-derived neurotrophic factor receptor alpha-like) was analyzed using RT-qPCR, while plasma protein levels of FGF21 and GDF15 were quantified via ELISA. The results obtained were statistically analyzed by using Shapiro–Wilk, Mann–Whitney U, and Wilcoxon tests in Statistica 13 software. Untrained individuals demonstrated significant post-exercise upregulation of FGFR3, FGFR4, KLB, and GFRAL. FGF21 and GDF15 protein levels were consistently lower in trained individuals (p < 0.01), with no significant correlations between gene and protein expression. Trained individuals showed more stable expression of genes, while untrained individuals exhibited transient upregulation of genes after exercise. Full article

In recent decades, environmental requirements for reducing the toxic components emitted from vehicle exhausts have decreased drastically. Technologies for after-treatment of diesel vehicle emissions are being improved continuously in order to meet increasingly stringent regulations. Passenger cars are a significant source of air pollution, especially in urban areas. The EU has decided to phase out internal combustion engines. Stricter Real Driving Emissions (RDE) testing procedures have also been introduced, aiming to assess the emissions of nitrogen oxides (NO_x) and particle number (PN). The present work investigates the interaction between performance and smoke emissions of a diesel vehicle on a pre-established route in an urban environment with an everyday (normal) driving style. The results showed that when the vehicle is technically sound and meets its technical specifications, smoke emissions are within normal limits. Full article

Background: Systemic inflammatory markers have emerged as accessible and reproducible tools for oncologic risk stratification, yet their prognostic value in rectal cancer remains incompletely defined, particularly in acute surgical settings. This study aimed to assess six inflammation-based indices—NLR, PLR, MLR, SII, SIRI, and AISI—in relation to tumor stage, recurrence, and outcomes among patients undergoing emergency versus elective resection for rectal cancer. Methods: We retrospectively evaluated 174 patients treated between 2018 and 2024. Pre-treatment blood counts were used to calculate inflammatory indices. Clinical and pathological parameters were correlated with biomarker levels using univariate and multivariate analyses. Results: Pre-treatment inflammation markers were significantly elevated in patients requiring emergency surgery (e.g., NLR: 3.34 vs. 2.4, p = 0.001; PLR: 204.1 vs. 137.8, p < 0.001; SII: 1008 vs. 693, p = 0.007), reflecting advanced tumor biology and immune activation. Notably, these patients also had higher rates of stage IV disease (p = 0.029) and permanent stoma (p = 0.002). Post-treatment, recurrence was paradoxically associated with significantly lower levels of SII (p = 0.021), AISI (p = 0.036), and PLR (p = 0.003), suggesting a potential role for immune exhaustion rather than hyperinflammation in early relapse. Conclusions: Inflammatory indices provide valuable insights into both tumor local invasion and host immune status in rectal cancer. Their integration into perioperative assessment could improve prognostication, particularly in emergency presentations. Post-treatment suppression of these markers may identify patients at high risk for recurrence despite initial curative intent. Full article

The investigation of the neuromuscular components of fatigue in team sports, especially in developmental ages, is limited. This study aimed to examine the neuromuscular fatigue and recovery patterns in prepubertal and adult female handball players, focusing on the soleus (SOL) and tibialis anterior (TA) muscles. Fifteen prepubertal (11.1 ± 0.9 years) and fourteen adult (22.0 ± 3.4 years) females performed a sustained isometric plantar flexion at 25% of maximal voluntary contraction (MVC) until exhaustion. The electromyographic (EMG) activity of the SOL and TA, torque, and central activation ratio (CAR) were recorded throughout the experiment. Endurance time was similar between groups (girls: 104 ± 93.5 s; women: 94.4 ± 30.2 s, p > 0.05), and both demonstrated progressive increases in muscle activation, without significant group differences for SOL and TA EMG (p > 0.05). Following fatigue, the torque and soleus (SOL) EMG activity decreased significantly compared to the pre-fatigue values in both groups (p < 0.001) and recovered (p > 0.05) in prepubertal and adult females within the first 3 and 6 min, respectively. The CAR remained unchanged over time, without significant differences observed between age groups (p > 0.05). These findings suggest that neuromuscular responses to fatigue are comparable between prepubertal and adult females, but recovery is significantly faster in prepubertal girls. Consequently, these findings underscore the need for age-specific recovery strategies in training programs, with tailored exercise-to-rest ratios to enhance performance and reduce fatigue during handball-specific activities. Full article

Background: This study aimed to investigate the acute changes in muscle and tendon viscoelastic properties in response to a progressive treadmill VO₂max test among professional male soccer players. Methods: Bilateral assessments at five sites—the Achilles tendon (AT), biceps femoris, semitendinosus, rectus femoris (RF), and sternocleidomastoid (SCM)—measured tone (oscillation frequency), dynamic stiffness, logarithmic decrement (elasticity), stress relaxation time, and creep. Each site was probed five times and values averaged. Repeated-measures ANOVA (Time × Side) with Bonferroni correction tested pre- to post-exercise changes; Pearson’s r examined associations with VO₂max. Results: Significant Time effects (all p < 0.05) were observed for RF frequency (η_p² = 0.226), RF creep (η_p² = 0.144), AT stiffness (η_p² ≈ 0.035), AT frequency (η_p² = 0.035), and SCM frequency (η_p² = 0.037). Post-exercise, right AT stiffness fell by 65 ± 14 N/m (p = 0.015), while left AT stiffness rose by 22 ± 9 N/m (p = 0.015). RF stiffness decreased by 28 ± 6 N/m (p < 0.001) and tone by 1.2 ± 0.3 Hz (p < 0.001), with creep (+0.08 ± 0.02; p < 0.001) and relaxation time (+1.5 ± 0.7 ms; p < 0.001) increasing. SCM tone declined by 0.8 ± 0.4 Hz (p = 0.010). Baseline RF properties—frequency (r = −0.597), stiffness (r = −0.59), relaxation time (r = 0.53), and creep (r = 0.48)—correlated moderately with VO₂max (all p < 0.05). Conclusions: These findings suggest that viscoelastic adaptations to exhaustive aerobic exercise are tissue- and side-specific, and that rectus femoris viscoelastic properties may serve as potential indicators of endurance readiness. Full article

This work presents an exhaustive parametric study of the multi-scale residual stress analysis on arbitrary substrate geometry based on a one-way-coupled thermo-mechanical model in an Atmospheric Plasma Spray process. It was carried out by modifying key process parameters, such as substrate surface geometry, substrate pre-heating temperature, and coating thickness, in an Al₂O₃ coating process on an aluminium substrate. The relationship of these parameters to the generation of quenching stress, thermal stress and residual stress was analysed at three different sub-modelling scales, from the macroscopic dimension of the substrate to the microscopic dimension of the splats. The thermo-mechanical phenomena occurring during the deposition process at the microscopic level were discussed in the proposed cases. Understanding these phenomena helps to optimise the parameters of the coating process by identifying the underlying mechanisms responsible for the generation of residual stresses. The simulated residual stresses of the 200 μm Al₂O₃ outer coated aluminium cylinder were experimental validated using the incremental high-speed micro-hole drilling and milling method. Full article

Solid oxide fuel cell (SOFC) systems often employ metallic cathode air pre-heaters (CAPHs), frequently made from alloys with high chromium (Cr) content, to recover thermal energy from exhaust gases and pre-heat incoming air and fuel. Cr evaporation from metallic CAPHs can poison SOFC cathodes, reducing their durability. To mitigate this, we investigated controlled pre-oxidation of a FeCrAl alloy (alloy 318) to form a protective alumina scale by self-growing, assessing its impact on and oxidation resistance and Cr retention capability for CAPH applications. The effects of pre-oxidation were investigated across a temperature range of 800 to 1100 °C and dwelling times of 0.5 to 4 h. The formed oxide scales were characterised using gravimetry in combination with advanced analytic techniques, such as SEM/EDX, STEM/EDX, TEM, and XRD. Subsequently, the pre-oxidised FeCrAl alloys were characterised with respect to the oxidation rate and Cr₂O₃ evaporation in a tubular furnace at 850 °C, with 6.0 L/min air flow and 3 vol% H₂O to simulate the SOFC cathode environment. TEM analysis confirmed that the FeCrAl alloys formed alumina scales with 10 nm and 34 nm thickness after 1 h of pre-oxidation at 900 and 1100 °C, respectively. The corrosion and Cr₂O₃ evaporation rates of the FeCrAl alloy at 850 °C in humidified air were shown to be dramatically decreased by pre-oxidation. It was found that the mechanisms of oxidation and Cr₂O₃ evaporation were found to be controlled by the formation of different alumina phases during the pre-oxidation. Measurements of Cr₂O₃ evaporation and weight gain revealed that the alloy 318 pre-treated at 1100 °C for 1 h will form an α-Al₂O₃ scale, leading to a 98% reduction of the oxidation rate and 90% reduction of Cr₂O₃ evaporation compared to the non-oxidised alloy 318 under simulated SOFC cathode conditions. Full article

Background: Hypothermia at admission and in the following days is a major risk factor for neonatal mortality in both high- and low-resource settings. Implementing hypothermia prevention procedures is not an easy goal to achieve, and the few studies currently available in low-income countries focus mainly on temperature at admission. Deviation from normothermia does not exhaust its effects upon admission, with a demonstrated negative impact of hypothermia also during the first days of life. Objective: The aim of this study was to evaluate the effectiveness of bundled interventions in preventing neonatal hypothermia at admission and during hospitalization in a low-resource setting. Methods: This was a retrospective, observational, before–after study comparing a pre- (December 2023–February 2024) and a post-quality improvement intervention period (April–June 2024). The outcome measures included admission temperature, average temperature during hospitalization, number of hypothermia episodes, temperature checks per day during hospitalization, and mortality. Results: From the pre- to the post-intervention period, the median admission temperature increased from 35.6 °C to 36.0 °C (p = 0.004). Median temperature during hospitalization increased from 36.3 °C to 36.7 °C (p < 0.0001). Mild and moderate hypothermia episodes decreased from 1.0 to 0.5 and from 0.7 to 0.2 episodes per day (p < 0.0001). Conclusions: In a Sub-Saharan referral hospital, the implementation of bundled interventions to maintain the warm chain improved neonatal temperature at admission and during hospitalization, and reduced hypothermia episodes during hospitalization. Full article

The COVID-19 pandemic, caused by SARS-CoV-2, has had a profound impact on global health, with nearly 800 million cases reported in the Americas alone. The clinical presentation of the disease is highly variable, with approximately half of all patients experiencing severe symptoms. This variability confounds the complex interplay between immune responses and disease severity. Severe cases are often characterized by elevated levels of inflammatory cytokines. Over 88% of COVID-19 patients have multiple comorbidities; factors such as age and pre-existing conditions further modulate immune responses and contribute to the severity of the disease. While some studies have reported differences in cytokine profiles between severity groups, larger, well-designed cohorts are needed to clarify these relationships. Natural Killer cells, which are critical for the innate immune response against SARS-CoV-2, are often impaired and contribute to immune exhaustion. In addition, SARS-CoV-2 evades innate immune defenses through accessory proteins that inhibit interferon signaling and exacerbate cytokine storms and inflammation. This integrative review aims to synthesize findings from 2020 onward and provide insights into the innate immune responses induced by SARS-CoV-2 and their contributions to disease pathogenesis. Understanding cytokine dynamics, NK cell behaviors, and viral immune evasion strategies is critical for advancing therapeutic approaches. Full article

To modernize electrical power systems on isolated islands, countries around the world have increased their interest in combining green energy with conventional power plants. Wind energy (WE) is the most adopted renewable energy source due to its technical readiness, competitive cost, and environmentally friendly characteristics. Despite this, a high penetration of WE in conventional power systems could affect their stability. Moreover, these isolated island power systems face frequency deviation issues when operating in hybrid generation mode. Generally, under contingency or transient conditions for hybrid isolated wind–diesel power systems (WDPSs), it is only the diesel generator that provides inertial support in frequency regulation (FR) because wind turbines are unable to provide inertia themselves. Frequency deviations can exceed the pre-defined grid code limits during severe windy conditions because the diesel generator’s inertial support is not always sufficient. To overcome this issue, we propose a control strategy named emulation inertial and proportional (EI&P) control for Variable-Speed Wind Turbines (VSWTs). VSWTs can also contribute to FR by releasing synthetic inertia during uncertainties. In addition, to enhance the effectiveness and smoothness of the blade pitch angle control of WTs, a pitch compensation (PC) control loop is proposed in this paper. The aim of this study was to provide optimal primary frequency regulations to hybrid wind–diesel power systems (WDPSs). Therefore, the hybrid WDPS on San Cristobal Island was considered in this study. To achieve such goals, we used the above-mentioned proposed controls (EI&P and PC) and optimally tuned them using the Student-Psychology-Based Algorithm (SPBA). The effectiveness of this algorithm is in its ability to provide the best optimum controller gain combinations of the proposed control loops. As a result, the FD in the WDPS on San Cristobal Island was reduced by 1.05 Hz, and other quality indices, such as the integral absolute error (IAE), integral square error (ISE), and controller quality index (Z), were improved by 159.65, 16.75, and 83.80%, respectively. Moreover, the proposed PC control, which was further simplified using exhaustive searches, resulted in a reduction in blade pitch angle control complexity. To validate the results, the proposed approach was tested under different sets of perturbations (sudden loss of wind generator and gradual increase in wind speed and their random behavior). Furthermore, hybrid systems were tested simultaneously under different real-world scenarios, like various sets of load or power imbalances, wind variations, and their combinations. The Simulink results showed a significant improvement in FR support by minimizing frequency deviations during transients. Full article

Over the past several decades, viral vector-based vaccines have emerged as some of the most versatile and potent platforms in modern vaccinology. Their capacity to deliver genetic material encoding target antigens directly into host cells enables strong cellular and humoral immune responses, often superior to what traditional inactivated or subunit vaccines can achieve. This has accelerated their application to a wide array of pathogens and disease targets, from well-established threats like HIV and malaria to emerging infections such as Ebola, Zika, and SARS-CoV-2. The COVID-19 pandemic further highlighted the agility of viral vector platforms, with several adenovirus-based vaccines quickly authorized and deployed on a global scale. Despite these advances, significant challenges remain. One major hurdle is pre-existing immunity against commonly used vector backbones, which can blunt vaccine immunogenicity. Rare but serious adverse events, including vector-associated inflammatory responses and conditions like vaccine-induced immune thrombotic thrombocytopenia (VITT), have raised important safety considerations. Additionally, scaling up manufacturing, ensuring consistency in large-scale production, meeting rigorous regulatory standards, and maintaining equitable global access to these vaccines present profound logistical and ethical dilemmas. In response to these challenges, the field is evolving rapidly. Sophisticated engineering strategies, such as integrase-defective lentiviral vectors, insect-specific flaviviruses, chimeric capsids to evade neutralizing antibodies, and plug-and-play self-amplifying RNA approaches, seek to bolster safety, enhance immunogenicity, circumvent pre-existing immunity, and streamline production. Lessons learned from the COVID-19 pandemic and prior outbreaks are guiding the development of platform-based approaches designed for rapid deployment during future public health emergencies. This review provides an exhaustive, in-depth examination of the historical evolution, immunobiological principles, current platforms, manufacturing complexities, regulatory frameworks, known safety issues, and future directions for viral vector-based vaccines. Full article