Search Results (108)

Background/Objectives: The bidirectional selection of the Roman low- (RLA) and Roman high-avoidance (RHA) rat strains for extremely slow vs. very rapid acquisition of the two-way (shuttle-box) avoidance response has generated two divergent phenotypic profiles: RHA rats exhibit a behavioural pattern and gene expression profile in the frontal cortex and hippocampus (HPC) that are relevant to social and attentional/cognitive schizophrenia-linked symptoms; on the other hand, RLA rats display phenotypic traits linked to increased anxiety and sensitivity to stress-induced depression-like behaviours. The present studies aimed to evaluate the enduring and potentially positive effects of neonatal handling-stimulation (NH) on the traits differentiating these two strains of rats. Methods: We evaluated the effects of NH on anxious behaviour, prepulse inhibition of startle (PPI), spatial working memory, and hormone responses to stress in adult rats of both strains. Furthermore, given the proposed involvement of neuronal/synaptic plasticity and neurotrophic factors in the development of anxiety, stress, depression, and schizophrenia-related symptoms, using Western blot (WB) we assessed the effects of NH on the content of brain-derived neurotrophic factor (BDNF), its trkB receptor and Polysialilated-Neural Cell Adhesion Molecule (PSA-NCAM), in the prefrontal cortex (PFC), anterior cingulate cortex (ACg), ventral (vHPC), and dorsal (dHPC) hippocampus of adult rats from both strains. Results: NH increased novelty-induced exploration and reduced anxiety, particularly in RLA rats, attenuated the stress-induced increment in corticosterone and prolactin plasma levels, and improved PPI and spatial working memory in RHA rats. These effects correlated to long-lasting increases of BDNF and PSA-NCAM content in PFC, ACg, and vHPC. Conclusions: Collectively, these findings show enduring and distinct NH effects on neuroendocrine and behavioural and cognitive processes in both rat strains, which may be linked to neuroplastic and synaptic changes in the frontal cortex and/or hippocampus. Full article

Redox regulation is crucial for the cardiac action potential, coordinating the sodium-driven depolarization, calcium-mediated plateau formation, and potassium-dependent repolarization processes required for proper heart function. Under physiological conditions, low-level reactive oxygen species (ROS), generated by mitochondria and membrane oxidases, adjust ion channel function and support excitation–contraction coupling. However, when ROS accumulate, they modify a variety of important channel proteins in cardiomyocytes, which commonly results in reducing potassium currents, enhancing sodium and calcium influx, and enhancing intracellular calcium release. These redox-driven alterations disrupt the cardiac rhythm, promote after-depolarizations, impair contractile force, and accelerate the development of heart diseases. Experimental models demonstrate that oxidizing agents reduce repolarizing currents, whereas reducing systems restore normal channel activity. Similarly, oxidative modifications of calcium-handling proteins amplify sarcoplasmic reticulum release and diastolic calcium leak. Understanding the precise redox-dependent modifications of cardiac ion channels would guide new possibilities for targeted therapies aimed at restoring electrophysiological homeostasis under oxidative stress, potentially alleviating myocardial infarction and cardiovascular dysfunction. Full article

The increasing prevalence of stress-related disorders necessitates accurate and efficient detection methods for timely intervention. This study explored the potential of heart rate variability as a biomarker for detecting mental stress using a publicly available dataset. A total of 93 heart rate variability features extracted from electrocardiogram signals were analyzed to differentiate stress from non-stress conditions. Our methodology involved data preprocessing, feature computation, and three feature selection strategies—filter-based, wrapper, and embedded—to identify the most relevant heart rate variability features. By leveraging Recursive Feature Elimination combined with Nested Leave-One-Subject-Out Cross-Validation, we achieved a peak F1 score of 0.76. The results demonstrate that two heart rate variability features—the median absolute deviation of the RR intervals (the time elapsed between consecutive R-waves on an electrocardiogram), which is normalized by the median, and the normalized low frequency power—consistently distinguished the stress states across multiple classifiers. To assess the robustness and generalizability of our best-performing model, we evaluated it on a completely unseen dataset, which resulted in an average F1 score of 0.63. These findings emphasize the value of targeted feature selection in optimizing stress detection models, particularly when handling high-dimensional datasets with potentially redundant features. This study contributes to the development of efficient stress monitoring systems, paving the way for improved mental health assessment and intervention. Full article

Face recognition systems often falter when deployed in uncontrolled settings, grappling with low light, unexpected occlusions, motion blur, and the degradation of sensor signals. Most contemporary algorithms chase raw accuracy yet overlook the pragmatic need for uncertainty estimation and multispectral reasoning rolled into a single framework. This study introduces HUE-Net—a Human-centric, Uncertainty-aware, Event-fused Network—designed specifically to thrive under severe environmental stress. HUE-Net marries the visible RGB band with near-infrared (NIR) imagery and high-temporal-event data through an early-fusion pipeline, proven more responsive than serial approaches. A custom hybrid backbone that couples convolutional networks with transformers keeps the model nimble enough for edge devices. Central to the architecture is the perturbed multi-branch variational module, which distills probabilistic identity embeddings while delivering calibrated confidence scores. Complementing this, an Adaptive Spectral Attention mechanism dynamically reweights each stream to amplify the most reliable facial features in real time. Unlike previous efforts that compartmentalize uncertainty handling, spectral blending, or computational thrift, HUE-Net unites all three in a lightweight package. Benchmarks on the IJB-C and N-SpectralFace datasets illustrate that the system not only secures state-of-the-art accuracy but also exhibits unmatched spectral robustness and reliable probability calibration. The results indicate that HUE-Net is well-positioned for forensic missions and humanitarian scenarios where trustworthy identification cannot be deferred. Full article

This study presents the design, fabrication, and experimental validation of a two-finger robotic gripper featuring a 135° V-shaped fingertip profile tailored for lightweight waste collection in laboratory-scale environmental robotics. The gripper was developed with a strong emphasis on cost-effectiveness and manufacturability, utilizing a desktop 3D printer and off-the-shelf servomotors. A four-bar linkage mechanism enables parallel jaw motion and ensures stable surface contact during grasping, achieving a maximum opening range of 71.5 mm to accommodate common cylindrical objects. To validate structural integrity, finite element analysis (FEA) was conducted under a 0.6 kg load, yielding a safety factor of 3.5 and a peak von Mises stress of 12.75 MPa—well below the material yield limit of PLA. Experimental testing demonstrated grasp success rates of up to 80 percent for typical waste items, including bottles, disposable cups, and plastic bags. While the gripper performs reliably with rigid and semi-rigid objects, further improvements are needed for handling highly deformable materials such as thin films or soft bags. The proposed design offers significant advantages in terms of rapid prototyping (a print time of approximately 10 h), modularity, and low manufacturing cost (with an estimated in-house material cost of USD 20 to 40). It provides a practical and accessible solution for small-scale robotic waste-collection tasks and serves as a foundation for future developments in affordable, application-specific grippers. Full article

The research into human–canine interactions (HCIs) has grown substantially, yet limited attention has focused on the welfare of canines involved, particularly pet dogs owned by volunteer participants. To address this gap, we conducted a secondary analysis of data from a randomized controlled trial, examining canine welfare during an acute human stress protocol. Our methodology incorporated evidence-based screening tools, environmental modifications, researchers trained in canine behavior assessments and safe interactions, and canine stress monitoring using the Fear Free™ Canine Fear, Anxiety, and Stress (FAS) Spectrum. Dogs’ stress levels showed a non-significant increase from the rest to stressor phase (0.80 to 1.00, p = 0.073) and a significant decrease during recovery (1.00 to 0.48, p < 0.001). Only two dogs (7.6%) required withdrawal due to elevated stress levels, though these levels remained within acceptable safety parameters. The peak stress remained within acceptable limits, with only 24% (6 of 25) reaching an FAS score of two during the TSST. By final recovery, 96% of dogs achieved FAS scores of zero to one (Green Zone), indicating relaxed states. Salivary collection proved challenging, highlighting limitations in low-invasive physiological measurement techniques. Based on our findings and literature review, we propose standardized guidelines for HCI research, including thorough pre-screening, environmental preparation, researcher training, stress-monitoring protocols, and informed consent procedures emphasizing withdrawal rights. These guidelines aim to establish ethical standards for this rapidly expanding field, protecting canine participant welfare while enabling valuable research to continue. Full article

Neonatal endotracheal intubation (ETI) is a complex medical procedure that demands extensive training before practicing on real patients. Clinical studies indicate that the conventional training approach, typically conducted in idealized conditions with task trainers, has a low skill transferability rate compared to performance in the dynamic environments common in intensive care units (ICUs). According to cognitive load theory, novices encounter difficulties in multitasking scenarios, exhibiting performance declines due to competition among tasks for cognitive resources; experts, having achieved automaticity, have more cognitive resources to handle additional tasks present in high-stress environments and therefore exhibit less performance degradation. Current ETI skill assessment methods do not capture these differences in expertise. To bridge this gap, we develop an innovative dual-task mixed-reality (MR) simulator to evaluate the influence of cognitive distractors on ETI and substantiate effective performance measurement metrics. Results affirm that experts demonstrate superior proficiency in handling extraneous cognitive loads compared to novices. This has important implications for understanding how to measure novice performance in ETI settings. Taken together, the dual-task ETI training simulator and the associated automated skill evaluation metric system hold promise for enhancing training in neonatal ETI practice and ultimately leading to improved patient care outcomes. Full article

Chitin is one of the most abundant biopolymers in nature and is found mainly in the exoskeletons of crustaceans and insects, in the cell walls of fungi, and in some species of mollusks. Chitosan is a derivative of chitin; it is much more accessible and has a broader range of applications, including improving the quality of materials such as films, plastics, and concrete. The rheological properties of chitin and chitosan refer to their behavior against deformation and flow and their ability to resist structural changes under mechanical stress conditions. These properties are fundamental in applications where the aim is to control the texture, viscosity, and handling of these biopolymers. Three types of methods for the extraction of chitin and chitosan can be classified: the first is the chemical method, which presents high yields but uses reagents that generate toxic residues; the second is the biological method, which takes advantage of chemical reactions of microorganisms but in some cases has low yields compared to chemical extraction; and the third is the enzymatic method, which uses reagents with a low production of toxic residues. However, low extraction yields are also reported. One of the primary sources of chitin and chitosan is the residue of shellfish and crustaceans. However, a new source of obtaining these compounds is the black soldier fly, which has the same yields of biopolymers as shellfish. In addition, this is a residue of the black soldier fly larvae culture, where protein, oil, and biofertilizers are generated by the bioconversion of organic waste. This work proposes the black soldier fly as an alternative source for extracting chitin and chitosan, using organic methodologies that do not generate toxic residues and have high yields. Including these biopolymers in concrete elaboration could have positive results in terms of flexibility, compressive strength, and workability. Full article

Innovation through applied research is a valuable component of decision-making, as it alters process parameters and conditions that can be detected by special devices at high speed. In the case of materials such as steel, the thermal field analysis while a component is being heat treated is essential for controlling the evolution of its microstructure and its state of internal stresses. The mathematical models proposed in the observation of the behavior of this material can be consolidated by being implemented in computational systems that can be validated with physical measurements and, once a low uncertainty in the state predictions is acquired, established as management tools. In this sense, the recording of thermal histories represents a fundamental methodology to achieve the objective of diagnosing the result of handling the material. In this regard, it is proposed to implement automated testing devices that implement computer systems for recording, processing, calculating, estimating and transferring data to transform production lines’ efficiency by optimizing or canceling continuity. A prototype for measuring thermal histories with a degree of reproducibility and mitigation of systematic errors is presented as a utility model for analyzing the thermal processing of steels. Full article

Hericium erinaceus, commonly known as Lion’s Mane mushroom, presents a challenge for maintaining quality and shelf-life during post-harvest storage. This study investigates the impact of different temperatures (5 °C, 13 °C, and 21 °C) during 14 days of storage, on the physicochemical, microbiological, and bioactive characteristics of H. erinaceus. Respiration was measured as an indicator of physiological aging, showing that higher temperatures increased CO₂ production as well as O₂ depletion. Physicochemical assessments, including moisture content, pH, titratable acidity, weight loss, browning index, and firmness, demonstrated that refrigeration at 5 °C best preserved the mushrooms’ quality. Storage at 5 °C effectively minimized microbial proliferation, maintaining acceptable levels until day 7 but showing increased contamination by day 14. However, higher temperatures promoted antioxidant activity and total phenolic content, likely due to moisture loss and oxidative stress. These findings highlight the critical role of low-temperature storage in preserving both the physicochemical integrity and functional bioactivity of H. erinaceus, and suggest further research into packaging solutions and preservation strategies to optimize the post-harvest handling of H. erinaceus. Full article

Honey bees are known for their wide global distribution, their ease of handling, and their economic and ecological value. However, they are often exposed to a wide variety of stress factors. Therefore, it is essential for beekeepers to maintain healthy bee colonies. In this context, a balanced diet is recommended to support the growth of strong and healthy honey bee colonies. The purpose of this review is therefore to provide an overview of the nutritional requirements of Apis mellifera and their importance for the maintenance of healthy bee colonies. An adequate diet includes the consumption of sufficient amounts of proteins, carbohydrates, lipids, amino acids, vitamins, minerals, water, and essential sterols, and a diet based on multi-floral pollen is desirable. However, when honey bee colonies are located near agroecosystems with lower resource diversity, both brood rearing and colony longevity may decrease, making them more susceptible to parasites and diseases. On the other hand, efforts have been made to improve the health of honey bee colonies with the help of nutritional supplements consisting of a variety of components. Nevertheless, studies have shown that even with these supplements, a lack of nutrients can still be an issue for honey bee colonies. Furthermore, future research should focus on identifying nutritional supplements that can better replicate natural diet diversity and assessing long-term effects on honey bee colony resilience, especially in low-flowering areas. This review discusses the interaction between nutrient requirements and the effects of supplements on colony health. Full article

The green peach aphid, Myzus persicae, is a notorious pest worldwide. We collected a field population of the pest (FZQ-F) that exhibited high resistance to neonicotinoids. Exposure to neonicotinoids can induce oxidative damage in animals; however, it remains unclear whether antioxidant enzymes contribute to the innate immune response of neonicotinoid-resistant pests against high doses of insecticides. Treatment with sublethal doses of thiacloprid (LC₁₀ and LC₂₅) for 3, 6, 12, 24, 48, and 72 h resulted in significantly increased reactive oxygen species (ROS), including H₂O₂ content, in FZQ-F adults, indicating insecticide-induced oxidative stress. Additionally, the peroxidase activity in FZQ-F adults increased after thiacloprid exposure. Using comparative genomics, we identified 31 heme peroxidases in M. persicae with a typical “2Cys” structure, and phylogenetic analyses divided them into five groups. Comparative transcriptomes revealed that MpPxd2 and MpPxd4 were significantly upregulated in thiacloprid-treated aphids. Thiacloprid exposure significantly induced MpPxd2 and MpPxd4 expression levels, consistent with high H₂O₂ content and peroxidase activity. The knockdown of MpPxd2 or MpPxd4 in FZQ-F increased their susceptibility to imidacloprid, thiacloprid, and thiamethoxam, verifying the protective role of the heme peroxidases against neonicotinoids in aphids. The knockdown of MpPxd2 or MpPxd4 also led to shorter longevity and a low fecundity of adult aphids at 31 °C compared to controls. The results show that MpPxd2 or MpPxd4 is important in how cells respond to oxidative stress and may help resistant M. persicae pests to handle neonicotinoids. Full article

This Technical Note presents the continuation of the results regarding the synthesis, and physical and rheological evaluation of geopolymers for space applications. In the first part, the ability of these geopolymers to resist cosmic radiation was evaluated. This second part of the research aims to present the synthesis of the geopolymers, their physical and rheological evaluation, and the fabrication of panels for placement in nanosatellites and deployer systems. Manufacturing the 2 mm-thick geopolymer panel proved to be quite a challenge due to the nature of geopolymers. Three geopolymer formulations MKG-01, MKG-02, and MKG-03 were synthesized with an adequate balance of fluidity and malleability required to manufacture the panels. The formulations offered an open window of approximately 8 h. The mass loss in the formulations was closely related to the solid/liquid ratio of the formulation. The MKG-01 presented lower viscosity and low shear stress for handling, indicating a more homogeneous dispersion than the more viscous samples MKG-02 and MKG-03. Full article

Background: Leopard sharks (Triakis semifasciata) are abundant, coastal, eastern Pacific, mesopredatory sharks and are frequently managed in aquariums and zoos. Medical examinations are a routine part of good husbandry practices, but the handling protocols vary greatly between facilities. In this study, we compared the physiological stress responses of T. semifasciata associated with manual restraint and sedated handling under parallel holding and handling procedures in a 10 min interval. Methods: Blood was collected and analyzed for the hematocrit (Hct), lactate, glucose, beta-hydroxybutyrate (β-HB), pH, blood gasses, 1α-hydroxycorticosterone (1α-OHB), and corticosterone (B). Results: Overall, a minimal physiological stress response was observed in both groups. However, statistically significant increases in the PCO₂, β-HB and lactate occurred, while the pH_TC, SO₂, and BE decreased over time in the manual-restraint group. In the sedated group, the B, PCO₂, and lactate increased while the pH_TC, SO₂, and base excess (BE) decreased over time. When comparing treatments, the sedated group had a higher B and PCO_{2 TC} and a lower pH_TC, BE, and SO₂ than the manual-restraint group at the second time point. Conclusions: This study indicates that manual restraint is comparable to the described sedation in T. semifasciata for minimally invasive procedures. The overall results show that this species had low physiological stress responses to both methods. Full article

Maternal separation with early weaning (MSEW) is a popular early life stress (ELS) model in rodents, which emulates childhood neglect through scheduled mother-offspring separation. Although variations of ELS models, including maternal separation and MSEW, have been published for the mouse species, the reported results are inconsistent. Corticosterone is considered the main stress hormone involved in regulating stress responses in rodents—yet generating a robust and reproducible corticosterone response in mouse models of ELS has been elusive. Considering the current lack of standardization for MSEW protocols, these inconsistent results may be attributed to variations in model methodologies. Here, we compared the effects of select early wean diet sources—which are the non-milk diets used to complete early weaning in MSEW pups—on the immediate stress phenotype of C57BL/6J mice at postnatal day 21. Non-aversive handling was an integral component of our modified MSEW model. The evaluation of body weight and serum corticosterone revealed the early wean diet to be a key variable in the resulting stress phenotype. Interestingly, select non-milk diets facilitated a stress phenotype in which low body weight was accompanied by significant corticosterone elevation. Our data indicate that dietary considerations are critical in MSEW-based studies and provide insight into improving the reproducibility of key stress-associated outcomes as a function of this widely used ELS paradigm. Full article