Search Results (75)

Increasingly popular, recreational diving is a physical activity that takes place under extreme environmental conditions, which include hyperoxia, hyperbaria and exposure to cold water. The effects of these factors on the human body induce increased levels of reactive oxygen and nitrogen species in divers’ bodies, which may modulate damage-associated molecular pattern (DAMPs), their receptors and the antioxidant response. This study involved 21 divers who descended to a depth of 40 metres. Determinations of selected intracellular DAMPs (high-mobility group box protein 1,HMGB1, S100 calcium-binding proteins A9 and A8, S100A8 and S100A9, heat shock protein family A member 1A, HSPA1A (Hsp70), heat shock protein family B, (small) member 1, HSPB1(Hsp27), thioredoxin, TXN), their receptors (Toll-like receptor 4, TLR4 and receptors for advanced glycation end products, RAGE), nuclear factor-κB (NF-κB) and antioxidant defence markers were performed before, after and 1 h after the dive. A significant transient reduction in HMGB1 expression was observed immediately after the dive at both the mRNA and protein levels. We noted an increase in S100A9 expression, which occurred 1 h post-dive compared to the post-dive time point, and a post-dive decrease in TLR4 expression only at the mRNA level. Diving also influenced the expression of genes encoding key enzymes associated with glutathione synthesis, (glutamate-cysteine ligase, catalytic subunit, GCLC and glutathione synthetase, GSS), and reduced plasma glutathione levels. However, no significant changes were observed in the expression of NF-κB, nitric oxide synthase 2 (NOS2) or circulating DAMP receptors (TLR4 and RAGE). The findings suggest an adaptive response to diving-induced oxidative stress, which appears to be a protective mechanism against an excessive inflammatory response. To our knowledge, this is the first study to analyse the role of intracellular DAMPs in recreational divers. Full article

The location of faults in distribution networks represents a crucial line of defence, ensuring the safe and reliable operation of these networks. This paper puts forth a methodology for the location of short-circuit faults between phases within the context of a distribution network information physics system. Firstly, a distribution network topology identification model is constructed, and a switching function based on the characteristics of an interphase short-circuit fault current is constructed to form a physical layer interphase short-circuit preconceived fault set. Subsequently, methodologies for processing information perturbations, including distortion, delay, and failure, are proposed. Fault current information is then extracted to form an information layer fault current array. Ultimately, a similarity function is constructed to correlate the fault characteristics of the physical and information layers. This is achieved through the utilization of the variational bee colony algorithm, which is employed to address the aforementioned issue. The efficacy and suitability of the proposed methodology are assessed in the context of single-point and multi-point faults, dynamic topology alterations, and information perturbations in distribution networks. To this end, a real-world project in Hebei and the IEEE system are employed as illustrative examples. The methodology proposed in this paper can facilitate the rapid and precise location of phase-to-phase short-circuits in physical information systems of distribution networks, thereby enhancing the reliability of power supply in new intelligent distribution networks. Full article

Coastal zones, at the interface between land and sea, face increasing challenges from erosion, sea-level rise, and anthropogenic interventions, necessitating innovative tools for effective management and protection. This study introduces COAST-PRO_SIM, a novel numerical model specifically designed to predict shoreline evolution and assess the impacts of coastal defence structures on coastal morphology. Unlike existing models that often face a trade-off between computational efficiency and physical accuracy, COAST-PRO_SIM balances these demands by integrating two-dimensional wave propagation routines with advanced shoreline evolution equations. The model evaluates the effects of interventions such as breakwaters and groynes, enabling simulations of shoreline dynamics with reduced computational effort. By using high-resolution input data, COAST-PRO_SIM captures the interplay between hydrodynamics, sediment transport, and structural impacts. Tested on real-world case studies along the coasts of San Leone, Porto Empedocle, and Villafranca Tirrena, the model demonstrates its adaptability to diverse coastal environments. The results highlight its potential as a reliable tool for sustainable coastal management, allowing stakeholders to anticipate long-term changes in coastal morphology and design targeted mitigation strategies. Full article

Background/Objectives: To date, the health effects of karate have not been identified. Therefore, the aim of this article is to learn more about the health effects of karate training based on a review of current research. Methods: The Scopus database was searched from 2000 onwards for available articles related only to karate. The following intermediate phrases were not included: combat sport, fighting art, hand-to-hand combat, martial art, and self-defence system. The filter used was desk review analysis. Only 14 scientific articles (research papers and review papers) strictly on karate were found. The method of source material analysis and critical analysis of the source text was then used. Results: It was shown that kumite appears to require significantly more metabolic power than kata. Furthermore, the greater skill of karatekas is associated with their greater physical fitness, and long-term karate training attenuates the decline in dynamic visual acuity (DVA). The role of modified and individualised forms of karate training is also highlighted as important for the health of practitioners. Furthermore, long-term karate practice is associated with extensive modulation of immunological parameters. Karate training can also significantly improve motor skills. It can also play an important role in the development of willpower and personality traits that contribute to the well-being of its practitioners. Furthermore, nutritional and psychological interventions combined with karate training may improve cardiometabolic parameters, oxidative stress and inflammation. Karate training may also contribute to the prevention of osteoporosis and strengthen the left ventricular myocardium. Conclusions: It was found that there is a paucity of contemporary research on the health effects of karate training. In addition, they are limited to the individuals studied, so that generalisations about these effects in the general population of karate practitioners cannot be made. Full article

Background/Objectives: Salivary immunoglobulin A (IgA) is a mediator of local immunity and host defence. Altered IgA levels may predispose to bacterial invasion of the mucosa in the gastrointestinal tract, including the oral cavity. Our study aimed to present the diagnostic trends related to salivary IgA in health and disease based on a bibliometric analysis of published papers between 2009 and 2024. Methods: By 14 September 2024, 1247 English original articles were found in the database Web of Science. We selected 838 records considering the diagnostic usefulness of IgA in human subjects. Based on bibliographic data, we created citation and keyword co-occurrence maps using VOSviewer 1.6.20. Results: Most articles belonged to the “Sport Sciences” category (n = 169), followed by the “Immunology” category (n = 93). The Brazilian researcher Alexandre Moreira from the University of Sao Paulo had the most published and most frequently cited papers. Most of the included articles came from the USA (n = 158), England (n = 105), Brazil (n = 95), and Japan (n = 95). The most cited article described research on IgA in response to SARS-CoV-2 infection (n = 690), but the subsequent two papers considered the role of salivary IgA in the dysbiosis of the intestinal microbiota in inflammatory bowel diseases (n = 272) and the formation of systemic immune responses from the gastrointestinal tract (n = 245). Conclusions: Salivary IgA is a widely evaluated diagnostic marker in both patients and healthy individuals. Numerous reports have identified its changes as a result of physical exertion in various groups of athletes, during infections (including SARS-CoV-2) and in the course of local diseases (e.g., periodontal disease) or systemic diseases (e.g., inflammatory bowel disease). Full article

This review explores the dual role of skeletal muscle as both a mechanical and endocrine organ, highlighting its contributions to overall health and its adaptability to various inputs such as nutrition, hormones, exercise, and injuries. In addition to its role in metabolism and energy conversion, skeletal muscle secretes signalling molecules called myokines (at rest) and exerkines (during/after physical exercise), which communicate with other organs like the brain, the cardiovascular system, and the immune system. Key molecules such as interleukins, irisin, and myostatin are discussed for their roles in mediating muscle health and inter-organ communication. This work also focuses on the muscle–gut axis, emphasising the bidirectional interaction between skeletal muscle and the gut microbiota, a complex ecosystem influencing immune defence, digestion, and metabolism. Muscle activity, particularly exercise, alters the gut microbial composition, promoting beneficial species, while gut-derived metabolites like short-chain fatty acids (SCFAs) impact muscle metabolism, mitochondrial function, and insulin sensitivity. Dysbiosis, or an imbalanced microbiota, can lead to muscle atrophy, inflammation, and metabolic dysfunction. This evidence highlights emerging research into myokines and exerkines as potential therapeutic targets for managing conditions like muscle decline, ageing, and metabolic diseases through muscle–gut interactions. Full article

This paper presents an advanced framework for securing 6G communication by integrating deep learning and physical layer security (PLS). The proposed model incorporates multi-stage detection mechanisms to enhance security against various attacks on the 6G air interface. Deep neural networks and a hybrid model are employed for sequential learning to improve classification accuracy and handle complex data patterns. Additionally, spoofing, jamming, and eavesdropping attacks are simulated to refine detection mechanisms. An anomaly detection system is developed to identify unusual signal patterns indicating potential attacks. The results demonstrate that machine learning (ML) and hybrid models outperform conventional approaches, showing improvements of up to 85% in bit error rate (BER) and 24% in accuracy, especially under attack conditions. This research contributes to the advancement of secure 6G communication systems, offering details on effective defence mechanisms against physical layer attacks. Full article

Background and Objectives: Atherosclerosis, driven by dyslipidaemia and oxidative stress, is a leading cause of cardiovascular morbidity and mortality. This study evaluates the effects of vigorous-intensity bodybuilding exercise (VIBBE) on atherosclerosis biomarkers—including paraoxonase-1 (PON1) and arylesterase (ARE) activities—and lipid profiles in male bodybuilders who do not use anabolic-androgenic steroids. Comparisons were made with individuals engaged in moderate-intensity aerobic exercise (MIAE), as well as overweight/obese sedentary (OOS) and normal-weight sedentary (NWS) individuals. Materials and Methods: A cross-sectional study was conducted involving 122 healthy male participants aged 18–45 years, divided into four groups: VIBBE (n = 31), OOS (n = 30), MIAE (n = 32), and NWS (n = 29). Anthropometric assessments were performed, and fasting blood samples were collected for biochemical analyses, including lipid profiles and PON1 and ARE activities. Statistical analyses compared the groups and evaluated correlations between adiposity measures and atherosclerosis biomarkers. Results: The VIBBE group exhibited significantly lower levels of low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), and logarithm of the TG to high-density lipoprotein cholesterol (HDL-C) ratio [log(TG/HDL-C)] compared to the OOS group (p < 0.05 for all), indicating improved lipid profiles. However, these improvements were not significant when compared to the NWS group (p > 0.05), suggesting that VIBBE may not provide additional lipid profile benefits beyond those associated with normal weight status. PON1 and ARE activities were significantly lower in the VIBBE group compared to the MIAE group (p < 0.05 for both), suggesting that VIBBE may not effectively enhance antioxidant defences. Correlation analyses revealed significant inverse relationships between PON1 and ARE activities and adiposity measures, including body mass index (BMI), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), body fat percentage (BFP), fat mass index (FMI), and obesity degree (OD) (p < 0.05 for all). Positive correlations were observed between oxLDL and log(TG/HDL-C) and adiposity measures (p < 0.05 for all). Conclusions: Vigorous-intensity bodybuilding exercise improves certain lipid parameters compared to sedentary obese individuals but does not significantly enhance antioxidant enzyme activities or further improve lipid profiles beyond those observed in normal-weight sedentary men. Conversely, moderate-intensity aerobic exercise significantly enhances PON1 and ARE activities and improves lipid profiles, offering superior cardiovascular benefits. These findings underscore the importance of incorporating moderate-intensity aerobic exercise into physical activity guidelines to optimize cardiovascular health by balancing improvements in lipid metabolism with enhanced antioxidant defences. Full article

The bird cherry-oat aphid, Rhopalosiphum padi (L.), is an economically significant pest of pasture grasses, the latter being capable of hosting several fungal endophyte–perennial ryegrass symbiota rich in alkaloids and toxic to vertebrates and invertebrates. Measuring aphid feeding behaviour can provide insights into the effectiveness and mode of action of different fungal endophytes. This study investigated the effects of different Epichloë–perennial ryegrass symbiota on the feeding behaviour of R. padi using the electrical penetration graph technique while also assessing the aphid life history. In most cases, endophytes had significant feeding deterrence and paired fecundity and mortality effects. But, in some instances, endophytes with the highest aphid mortality did not significantly deter feeding, suggesting a more complicated scenario of interactions between the relative concentration of metabolites, e.g., host plant defence response metabolites and alkaloids, and/or physical changes to leaf morphology. Overall, this study sheds light on the mode of action of Epichloë endophytes against aphids and highlights the importance of Epichloë–perennial ryegrass symbiota in the management of insect pests such as aphids in pasture-based grazing systems. Full article

Plant defence mechanisms, including physical barriers like toughened bark and chemical defences like allelochemicals, are essential for protecting them against pests. Trees allocate non-structural carbohydrates (NSCs) to produce secondary metabolites like monoterpenes, which increase during biotic stress to fend off pests like the Eurasian spruce bark beetle, ESBB (Ips typographus). Despite these defences, the ESBB infests Norway spruce, causing significant ecological damage by exploiting weakened trees and using pheromones for aggregation. However, the mechanism of sensing and resistance towards host allelochemicals in ESBB is poorly understood. We hypothesised that the exposure of ESBB to spruce allelochemicals, especially monoterpenes, leads to an upsurge in the important detoxification genes like P450s, GSTs, UGTs, and transporters, and at the same time, genes responsible for development must be compromised. The current study demonstrates that exposure to monoterpenes like R-limonene and sabiene effectively elevated detoxification enzyme activities. The differential gene expression (DGE) analysis revealed 294 differentially expressed (DE) detoxification genes in response to R-limonene and 426 DE detoxification genes in response to sabiene treatments, with 209 common genes between the treatments. Amongst these, genes from the cytochrome P450 family 4 and 6 genes (CP4 and CP6), esterases, glutathione S-transferases family 1 (GSTT1), UDP-glucuronosyltransferase 2B genes (UDB), and glucose synthesis-related dehydrogenases were highly upregulated. We further validated 19 genes using RT-qPCR. Additionally, we observed similar high expression levels of detoxification genes across different monoterpene treatments, including myrcene and α-pinene, suggesting a conserved detoxification mechanism in ESBB, which demands further investigation. These findings highlight the potential for molecular target-based beetle management strategies targeting these key detoxification genes. Full article

The Cyber Evaluation and Management Toolkit (CEMT) is an open-source university research-based plugin for commercial digital model-based systems engineering tools that streamlines conducting cybersecurity risk evaluations for complex cyber-physical systems. The authors developed this research tool to assist the Australian Defence Force (ADF) with the cybersecurity evaluation of complicated systems operating in an increasingly contested and complex cyber environment. This paper briefly outlines the functionality of the CEMT including the inputs, methodology, and outputs required to apply the toolkit using a sample model of the process applied to a generic insider threat attack. A face validity trial was conducted on the CEMT, surveying subject-matter experts in the field of complex cybersecurity analysis and risk assessment to present the generic case study and gather data on the expected benefits of a real-world implementation of the process. The results of the face validity broadly supports the effectiveness and usability of the CEMT, providing justification for industry research trials of the CEMT. Full article

Due to their physical and mechanical properties, niobium products are used in the nuclear power industry, chemical industry, electronics, medicine and in the defence industry. Traditional manufacturing technology for these products is characterized by long production cycles and significant material losses during their surface machining. This paper presents the results of a study on the fabrication of niobium products by Spark Plasma Sintering (SPS). Structural and mechanical tests were conducted on the products obtained, as well as a comparative analysis with the properties of products obtained using traditional technology. Based on the analysis of the test results obtained, recommendations were made for the sintering of Nb powders. It was found that the optimum temperature for sintering the powder is 2000 °C as the density of the material obtained is close to the theoretical density. The microstructure obtained is comparable to samples obtained by the traditional method after recrystallization annealing. Samples obtained according to the new technology are characterized by higher mechanical properties R_p0.2 and R_m and the highest hardness. Full article

Doctoral education has been shaped by a continuous interaction between the research community and representatives of the governmental authorities. In Sweden, doctorates were organised into structured educational programmes in 1969. In this study, the development of doctoral education in Medical Radiation Physics at Lund University, Sweden, was analysed over approximately 50 years, in terms of quantitative parameters related to throughput rate and scientific production making up the doctoral theses. Theses from two time periods (1970 to 1999 versus 2001 to 2023) were compared in terms of the total number of full papers (either accepted or in manuscript form), number of accepted full papers and number of accepted full papers as first author. For all three categories of included papers, median values were not significantly different between the two time periods while the variances were significantly smaller for the period 2001 to 2023 (level of significance 0.05). The time between admission and thesis defence decreased with time, according to linear correlation analysis, while the number of supervisors increased. Doctoral theses showed a significantly more uniform composition after a major political reform in 1998. Hence, doctoral education can be described as becoming more efficient and predictable. It is suggested that the primary causes include the introduction of individual study plans and secured personal financial support. The increased efficiency can also be problematised regarding, for example, insufficient independence and limited freedom of research. Full article

This article delves into the intricacies of human defences in various domains, including the biological and psychological responses to protect oneself, and the abstract concept of sacrificing one’s life to uphold ethical, moral, religious, and spiritual values. While physical, psychological, and moral values have been attended to in counselling, regard for the religious and spiritual aspects is still developing. As the author writes from a Christian perspective, Christian faith and values are considered. It is posited that a study of human nature, as presented in the Christian Bible, can facilitate a profound comprehension of human defences. The paper scrutinizes the correlation between “human defences” and “Christian spirituality” through a Christian lens on human nature. Furthermore, it introduces the idea of “spiritual defence” and how it is related to a spiritual awakening. Full article

Despite substantial research examining caterpillar–plant interactions, changes in the feeding behaviour of lepidopteran larvae as they develop are poorly understood. In this study, we investigated ontogenetic changes in the behaviour of Helicoverpa armigera larvae feeding on reproductive structures of pigeonpea (Cajanus cajan). Specifically, we examined the preference for and avoidance of pigeonpea flowers and pods of first, second, third, and fourth instar H. armigera larvae. We also conducted a no-choice assay to compare the ability of third and fourth instar larvae to penetrate pigeonpea pod walls, which act as a physical defence against herbivory. When presented with a choice between pigeonpea pods and flowers, different instars behaved differently. First and second instar larvae largely avoided pigeonpea pods, instead feeding on flowers; third instar larvae initially avoided pods, but by 24 h, did not strongly discriminate between the structures; and fourth instars demonstrated a preference for pods. When initially placed on pods, first instars were slower than other instars to leave these structures, despite pods being suboptimal feeding sites for small caterpillars. We identified a clear instar-specific ability to penetrate through the pod wall to reach the seeds. Most third instar larvae were unable to penetrate the pod wall, whereas most fourth instars succeeded. Third instars suffered a physiological cost (measured by relative growth rate) when boring through the pod wall, which was not observed in fourth instars. Our study further illuminates the insect–plant interactions of the H. armigera–pigeonpea system and provides evidence for the significant changes in feeding behaviour that may occur during lepidopteran larval development. Full article