Decrease In Stress Research Articles

An analytical model for predicting the shear fracture behavior of discontinuities with multi-scale asperities incorporating the damage element method

Asperities within discontinuities play a critical role in contributing to shear resistance. However, their influence on the shear fracture behavior of discontinuities is constrained by size effects. Revealing and predicting the fracture process of discontinuities with multi-scale asperities is crucial for guiding engineering stability assessment. In this study, PFC2D was employed to simulate the microscopic fracture process of discontinuities with multi-scale asperities under shear loading conditions. The simulation revealed that first-order asperities predominantly experience wear failure, whereas second-order asperities primarily undergo shear failure. Based on these findings, the damage evolution equation for the microscopic elements of first-order asperities was formulated using classical wear theory, while the equation for second-order asperities employed Weibull distribution statistical theory. Consequently, an analytical model was developed that considers the influence of multi-scale asperities on the shear behavior of discontinuities incorporating the damage element method. Subsequently, this analytical model was validated against experimental data and numerical results, demonstrating its capability to accurately predict the rapid stress decrease following the peak point. Finally, the sensitivity of the model parameters was discussed.

Genetics of sorghum: grain quality, molecular aspects, and drought responses.

Sorghum kernel composition is a crucial characteristic that determines its functional qualities. The total protein content of sorghum grain increases under drought stress, but starch, protein digestibility, and micronutrient contents decrease. Sorghum (Sorghum bicolor L.) is a staple source of starch, protein, and micronutrients in Ethiopia, where it is a key ingredient in local foods like injera and traditional beverages such as tela and areke. It has adapted remarkably to the diverse climatic conditions and soils of both highland and lowland regions. However, grain quality is influenced by climate change, drought stress, and genotype-environment interactions. Under drought conditions, sorghum shows reduced starch content, protein digestibility, and micronutrient levels, as well as increased kernel hardness and total protein content. The genetic and geographic diversity of sorghum makes it an adaptable crop, essential for breeding and diversity studies. Genome-wide association studies (GWAS) have emerged as essential tools for identifying candidate genes linked to key traits, thereby advancing genetic improvement initiatives, particularly for Ethiopian sorghum landraces. Advances in genotyping techniques, particularly genotyping-by-sequencing (GBS) and association mapping, have facilitated the identification of quantitative trait loci (QTL) associated with grain quality, enhancing breeding efficiency and the development of resilient, high-quality sorghum varieties. This review explored the genetic and phenotypic diversity of sorghum, focusing on grain quality traits, molecular mechanisms, and responses to drought stress.

Effect of Axial Modification on the Meshing Performance of Involute Beveloid Gear Pair

In order to enhance the load-bearing capacity of the involute beveloid gear pair, this study proposes research on improving the contact stress through axial modification. Under the condition of segmented parabolic axial modification, the mathematical equation for the tooth flank of the beveloid gear is derived. A simulation meshing model for the beveloid gear pair is constructed to investigate the effects of different amounts and lengths of axial modification on the meshing performance, changes in flank and root stress, and transmission error before and after modification. The results indicate that as the modification amount increases, the maximum equivalent stress initially decreases and then exhibits a tendency towards stability. Moreover, an increase in modification length concentrates the contact zone towards the middle of the tooth flank while expanding the range of tooth root stress distribution, and it also leads to a decrease in maximum equivalent stress. The implementation of the modification has been observed to result in a reduction in cumulative transmission error and an effective reduction in edge load on the beveloid gear pair, which has been demonstrated to enhance the bearing capacity and transmission stability extension while also impacting the dynamic meshing performance.

Correlation between process conditions and mechanical film properties in foamed multilayer blown films

In the context of packaging with films, specific mechanical properties are of paramount importance. This can be achieved through the implementation of optimized manufacturing processes and the efficient utilization of raw materials. The foam extrusion process has the potential to enhance material efficiency. The foam structure impacts the mechanical properties due to replacing force-conducting material. Blown film extrusion represents a predominant production process in the packaging field, offering the potential for cost-effective mass production. Integration of these processes gives rise to intricate behavior patterns, attributable to interactions between the conditions governing the blown film and those governing foam extrusion. This affects the density reduction and the mechanical properties of the material. This study’s objective was to identify the significant parameters affecting mechanical properties and to gain insight into the mechanisms influencing the foam blown film process. The results demonstrated that combining foam and blown film extrusion markedly reduces the resulting film density, with a potential savings of up to 40% in plastic at 7% blowing agent content. The optimal conditions to produce small-cell foam structures include high die pressure gradients, which can be achieved by lowering the blown film die head temperature or increasing the mass flow rate of the foamed middle layer. Tensile stress and Youngs modulus decrease with increasing blowing agent content, as the gas-filled cells reduce structural integrity. Thinner films often show higher tensile strength due to better molecular orientation. At the same time, the mass ratio influences the mechanical properties by changing the polymer structure and cell distribution, which optimizes or weakens the mechanical properties. The study presents significant insights into the blown film foam extrusion process and investigates the correlations between density reduction and the resulting mechanical properties.

The Correlation Between Self-Disclosure, Academic Hardiness, and Academic Stress on Vocational High School Students

Implementing an independent curriculum aims to create a flexible teaching and learning process but often creates academic pressure that impacts student academic stress. In this case, students need to recognize the conditions and situations that exist so that self-disclosure becomes an important step that needs to be owned, as well as a resilient personality that makes students able to deal with stress and accept academic situations that arise as a step of self-development. The research was conducted on 238 students of vocational high school “X” students in Surabaya using multiple linear regression analysis techniques. The results showed that self-disclosure and academic hardiness correlate with vocational students' academic stress. Students with self-disclosure can express self-information, supported by the personality of academic hardiness, which makes a person stronger, resistant, and optimistic so that academic stress decreases. The following result shows that self-disclosure negatively correlates with vocational students' academic stress. Self-disclosure with the closest person can reduce academic stress because problems and conflicts in the surrounding environment can be expressed to their friends. The third hypothesis result shows that academic hardiness has a negative correlation with the academic stress of vocational students. Students with resilient personalities can deal with stressors positively because they can identify activities around them.

Rainfall seasonality shapes belowground root trait dynamics in an Amazonian tropical rainforest: A test of the stress‐dominance hypothesis

Abstract The stress‐dominance hypothesis (SDH) predicts that trait variation at the community level increases with the availability of limiting resources, driving spatial and temporal patterns in above‐ground plant functional trait expression. Here, we test the assumption that the SDH also applies to fine roots responding to spatial and temporal fluctuations in soil resource availability. We monitored fine root mass and functional root traits associated with resource acquisition, that is specific root length (SRL), specific root tip abundance (SRTA) and branching index (BI), and traits related to stress tolerance, such as root diameter (RD) and tissue density (RTD) in a Central Amazonian tree community. To test for spatial differences in root traits, we separated the uppermost organic (O‐A horizon, 0–5 cm) and mineral soil (B horizon, 5–15 cm) layers, and for temporal fluctuations, we investigated the relationship of precipitation on community‐level root variation over a period of 27 months. In accordance with the SDH, we found that fine roots in the O‐A horizon have on average 15% higher SRL, 23% higher BI, 32% higher SRTA and 15% lower RTD than those in the B horizon. Similarly, precipitation shifted the community over time to higher mean SRL, BI and SRTA (r = 0.92, 0.84 and 0.94, p < 0.0001 respectively), although trait shifts occurred in the trimester after the rainy season onset, revealing a time‐lag between rainfall patterns and community response. We also detected a positive increase in trait range for SRL and SRTA with lagged precipitation (r = 0.90 and 0.79, p < 0.0001). On the other hand, traits related to stress showed a weaker negative relationship with instantaneous precipitation (r = −0.7 and −0.57, p = 0.046 and p = 0.1 for RD and RTD, respectively). Our results supported the SDH predictions that root systems will become more acquisitive in areas with more resources, and that the community will shift to more acquisitive but also broader trait dispersion as hydric stress decreases. We conclude that although higher resource availability may increase competition for acquisition, trait overdispersion seems to promote species coexistence. Our results highlight how dynamic root systems can be in response to environmental cues, cautioning the common practice of making conclusions about root traits adaptations to environmental gradients based on a single sampling observation. Read the free Plain Language Summary for this article on the Journal blog.

Analysis and prediction of tensile properties based on a novel wide‐angle fabric/EPDM composite under different temperatures

AbstractThis study investigated the tensile properties of the wide‐angle fabric/ethylene‐propylene‐diene monomer (EPDM) composite (WFRC) under varying temperature conditions based on the macro‐ and mesoscopic structural characterization. The wide‐angle fabric was modeled using an improved “cross‐sectional path” method that precisely represents the yarn geometry by integrating warp and weft orientations within a non‐orthogonal coordinate system derived from optical micrographs. Tensile tests conducted across a temperature range from 25 to 150°C revealed that both stress and strain decrease with increasing temperature. Numerical simulations closely aligned with the experimental data, exhibiting a maximum relative error of only 2.5% at 90°C, thereby demonstrating the robustness of the simulation models in capturing the mechanical responses of WFRC. The findings underscore the predominant role of the rubber matrix in determining the mechanical properties of WFRC, while also highlighting that the fabric maintains excellent shape conformity with the rubber. This paper presents an effective methodology for analyzing the mechanical properties of WFRC under varying temperatures, laying the groundwork for future studies on the long‐term durability and failure mechanisms of WFRC under cyclic thermal loads, and broadening its applications across various engineering domains.Highlights The improved “cross section path” method is employed for fabric modeling. Macro‐ and mesoscopic modeling of the wide‐angle fabric/EPDM composite. The superelasticity of the rubber is integrated into the VUMAT subroutine. The numerical simulations closely align with the experimental data.

A method for stress and hardness characterization based on the amplitude spectrum features of magnetic Barkhausen noise

Abstract Hardness and residual stress on the surface serve as critical evaluation indicators for the quality of components in industrial manufacturing. However, determining their values becomes a substantial challenge when both these mechanical properties are variables. This study proposes a method for decoupling stress and hardness from the time–frequency domain of magnetic Barkhausen noise (MBN), aiming to distinguish between the two variable mechanical properties. Short-time Fourier transform is employed to obtain the amplitude spectrum of MBN, and features in both time and frequency domains are extracted. The relationship between the features of MBN and mechanical properties is examined. Our findings indicate that as hardness increases, the rate of change of MBN features with stress decreases. In contrast, at higher stress levels, the rate of change of MBN features with hardness increases. However, the frequency corresponding to the maximum value of the amplitude spectrum f max remains constant despite changes in stress but exhibits an increase with increasing hardness. A model based on planar polynomial functions related to hardness and stress is developed to achieve decoupling. The method would serve as a valuable reference for the decoupling of two or more mechanical properties.

Quantitative 3-D investigation of faulting in deep mining using Mohr–Coulomb criterion and slip weakening law

Assessing the risk of fault-slip rockburst is crucial for ensuring the safety of mining operations and effectively mitigating potential disasters. In this study, we propose an integrated 3-D numerical modeling framework combining the virtual fault (VF), 3-D Mohr–Coulomb criterion model (MC), and slip weakening model (SW) to investigate the dynamics of fault failure and coseismic slip induced by mining activities near faults. Our research focuses on the fault stress ratio (k) and how it responds to variables such as fault dip angle (φ), mining distance (Dm), fault frictional parameters (μs, μd, and Dc), and panel length (Wm) within a depth-dependent stress field. Our findings demonstrate that the k serves as a critical indicator of fault reactivity, with its sensitivity to φ and Dm, significantly heightening the potential for seismic activities. We found that footwall mining, in particular, affects fault stability more than hanging wall mining, often causing greater instability. Additionally, decreases in normal stress due to mining activities are found to be crucial in triggering fault reactivation and coseismic slip. The SW model reveals that k initially decreases with increasing slip and stabilizes as slip progresses, highlighting the critical role of evolving frictional properties in fault stability. Additionally, this study confirms that mining-induced fault slips exhibit self-similar behaviors analogous to natural faulting, with a proportional relationship between slip distribution and static stress drop, validated through robust numerical analysis. This study enhances the understanding of fault mechanics in mining-induced conditions and provides a robust framework for assessing seismic risks, offering practical insights for improving safety and stability in deep mining operations.

Pathophysiology of Group 3 Pulmonary Hypertension Associated with Lung Diseases and/or Hypoxia.

Pulmonary hypertension associated with lung diseases and/or hypoxia is classified as group 3 in the clinical classification of pulmonary hypertension. The efficacy of existing selective pulmonary vasodilators for group 3 pulmonary hypertension is still unknown, and it is currently associated with a poor prognosis. The mechanisms by which pulmonary hypertension occurs include hypoxic pulmonary vasoconstriction, pulmonary vascular remodeling, a decrease in pulmonary vascular beds, endothelial dysfunction, endothelial-to-mesenchymal transition, mitochondrial dysfunction, oxidative stress, hypoxia-inducible factors (HIFs), inflammation, microRNA, and genetic predisposition. Among these, hypoxic pulmonary vasoconstriction and subsequent pulmonary vascular remodeling are characteristic factors involving the pulmonary vasculature and are the focus of this review. Several factors have been reported to mediate vascular remodeling induced by hypoxic pulmonary vasoconstriction, such as HIF-1α and mechanosensors, including TRP channels. New therapies that target novel molecules, such as mechanoreceptors, to inhibit vascular remodeling are awaited.

Seed pretreatment with cloquintocet-mexyl protects wheat seedlings from fomesafen injury by promoting photosynthesis and decreasing oxidative stress.

Fomesafen is a selective herbicide widely used to control post-emergent broad-leaf weeds in soybean and peanut fields. Because of its persistent nature in soil, it can suppress subsequent crops, including wheat. There is limited information focusing on methods of protecting wheat from fomesafen injury by soil residue. Bioassay results showed slight variations in tolerance to fomesafen among 31 wheat cultivars. Soil-applied biochar (200 g m-2) could alleviate fomesafen injury at 2 mg L-1, and partially alleviate fomesafen injury at 4 mg L-1. Seed soaking in safeners cloquintocet-mexyl and mefenpyr-diethyl was more effective in protecting seedlings from fomesafen injury at 4 mg L-1 compared with 1,8-naphthalic anhydride, fenclorim or dichlormid. Indoor tests suggested that the combined application of biochar and cloquintocet-mexyl or mefenpyr-diethyl had a synergistic alleviating effect on wheat injury caused by fomesafen, which was further confirmed in a field trial. Wheat seeds treated with cloquintocet-mexyl increased expression of the fomesafen target protoporphyrinogen IX oxidase and light-harvesting chlorophyll a/b binding protein, leading to an increase in chlorophyll content and a decrease in oxidative stress of wheat exposed to fomesafen. Cloquintocet-mexyl treatment had no influence on the expression of P450 genes, toxic transport genes, most glutathione S-transferase (GST) genes, the enzyme activity of P450 or GSTs, and the metabolism rate of fomesafen. These results suggested that cloquintocet-mexyl acted by increasing photosynthesis and decreasing oxidative stress to alleviate injury to wheat exposed to fomesafen stress, showing no influence on fomesafen metabolism in wheat. This study provided valuable information for fomesafen injury management in wheat. © 2025 Society of Chemical Industry.

UW supplementation with AP39 improves liver viability following static cold storage

Static cold storage of donor livers at 4 °C incompletely arrests metabolism, ultimately leading to decreases in ATP levels, oxidative stress, cell death, and organ failure. Hydrogen Sulfide (H2S) is an endogenously produced gas, previously demonstrated to reduce oxidative stress, reduce ATP depletion, and protect from ischemia and reperfusion injury. H2S is difficult to administer due to its rapid release curve, resulting in cellular death at high concentrations. AP39, a mitochondrially targeted, slow-release H2S donor, has been shown to reduce ischemia-reperfusion injury in hearts and kidneys. Thus, we investigated whether the addition of AP39 during 3-day static cold storage can improve liver graft viability. At the end of storage, livers underwent six hours of acellular normothermic machine perfusion, a model of transplantation. During simulated transplantation, livers stored with AP39 showed reduced resistance, reduced cellular damage (ALT and AST), and reduced apoptosis. Additionally, bile production and glucose, as well as energy charge were improved by the addition of AP39. These results indicate that AP39 supplementation improves liver viability during static cold storage.

Influence of Mindfulness Techniques on Reducing Academic Stress and Enhancing Students' Concentration in Learning

This study examines the effect of mindfulness techniques on reducing academic stress and increasing concentration in students. With increasing academic demands, many students experience stress that interferes with the learning process. Mindfulness techniques, which emphasize full awareness, have been shown to be effective in reducing anxiety and improving mental well-being. The experimental method involved two groups of students: one group implemented mindfulness techniques, while the control group received no intervention. Data were collected through questionnaires measuring levels of academic stress and concentration before and after the intervention. The results indicated that the group practicing mindfulness experienced a significant decrease in stress and an increase in concentration compared to the control group. These findings support the use of mindfulness techniques as an effective strategy to help students and recommend their integration into higher education curricula for academic well-being.

Meditation and guided imagery show reduction in chronic stress and increase in mental health-related quality of life for college students

Objective: To explore the effects of guided imagery with progressive deep muscle relaxation (PDMR) and meditation programs on chronic stress perception and health related quality of life in college students. Participants: College students were recruited from a local private university in Northeast Pennsylvania. Participants were not concurrently enrolled in another weekly meditation class. Students were randomly assigned to a meditation group (n = 16) or guided imagery with PDMR (n = 17). Method: The study design was an experimental, repeated measures design with two groups and two independent variables: the Perceived Stress Scale and Health-Related Quality of Life (SF-36v2). Results: Students in both the meditation and guided imagery groups demonstrated a decrease in chronic stress and increase in their mental-health related quality of life midway through the 8-week program and maintained throughout. Conclusion: This research lends support for weekly participation in a mind-body class as a viable method to decrease stress for college students.

An mHealth Intervention to Support Psychosocial Wellbeing of Racial and Ethnically Diverse Families in the NICU.

To assess the effectiveness of an mHealth neonatal intensive care unit (NICU) parent support smartphone application to improve psychosocial well-being, specifically reduced stress and anxiety, increased parenting competence, and improved social support among a diverse group of parents with infants born preterm in three Chicago-area NICUs. A time-lapsed, quasi-experimental design in which control participants were enrolled and then intervention participants enrolled. Data collection occurred at three timepoints: NICU admission (AD), discharge (DC), and 30 days post-discharge (DC+30). Validated outcome measures included parenting sense of competence (PSOC), stress, anxiety, and social support. Intention to treat analyses included 400 participants (156 intervention; 244 control). After covariate adjustment, a significant increase in PSOC (AD-DC, DC+30), decrease in stress (AD--DC+30), decrease in anxiety (AD-DC, DC+30), and increase in social support (AD-DC) were noted but did not differ by study arm. However, secondary analysis of parents with babies born at <32-weeks gestational age (GA) (156 participants) showed decrease in stress (AD--DC+30) that was greater in intervention vs control group (p=0.03). Among intervention participants who were Black, a significant increase in social support (AD-DC) total score (p=0.01), and two subscales of Emotional/Informational support (p=0.02) and Positive Social Interaction (p=0.02) were found. This novel mHealth intervention shows evidence of reduced stress and anxiety while increasing social support among some subsets of parents at high risk of negative psychosocial experiences in the NICU, potentially enhancing outcomes for infants born preterm by ensuring that parents are less stressed and better supported.

Synthesis of reusable cement materials through photochemical modification of marble powder for composite structures.

Sustainability and environmental protection are reshaping industries, including construction, where sustainability plays a crucial role in its influence on global resource consumption and waste management. The current study has developed a reusable cement material by photo-chemical surface modification of marble powder, achieved by reacting glycidyl methacrylate with carbonate functionality. This innovative modified marble powder boosts the reusability of construction materials, unlocking new possibilities for sustainable building practices. By transforming waste into valuable resources, we minimize raw material consumption, foster recycling, and advance circular economy principles in the construction industry. The difference in unmodified (22.9nm) and modified (23-27nm) marble powder particle sizes was used to assess the effectiveness of surface modification technique. Compared to non-reusable counterpart (20.34MPa), the reusability has come at the cost of a decrease in compression stress (11.30MPa, 10.89MPa, and 10.57MPa). Overall, photochemically modified marble powder for its reusability is a groundbreaking approach that offers substantial environmental, economical, and technical advantages, making it an appealing choice for the construction industry.

Nitinol Reactive Oxygen Assist Gas Laser Micromachining: Demystifying the Implications Imposed Upon Pseudoelasticity and the Shape Memory Effect for Nickel-Titanium Alloys

Herein, a novel investigation examines a long-pulse microsecond laser cutting process with an oxygen assist gas and the subsequent effects on martensitic phase transformations for binary nickel-titanium alloys. To establish a comprehensive comparative analysis, a reactive oxygen assist gas process, a standard inert argon assist gas process, and athermal femtosecond laser micromachining are studied in order to form a complete analytical assessment of how laser processing can inflict implications upon pseudoelasticity and shape memory. In-situ thermography reveals an approximate 1.5-times increase in thermal area for an argon assist gas when compared to oxygen. In conjunction with thermal analysis, electron backscatter diffraction and optical microscopy demonstrates 1.7 to 25 μm of epitaxial grain recrystallization associated with the elevated level of thermal propagation. Low cycle fatigue testing of pseudoelastic performance realizes a 12.7 % decrease in the achievable upper plateau stress when comparing long-pulse cutting to femtosecond cutting. Furthermore, when the laser power exceeds 30 W, the ultimate tensile strength suffers notable reductions of 25 % and 40 % for the oxygen and argon processes respectively when compared to femtosecond micromachining. Bend and free recovery testing provides insights into shape memory performance of the endothermic phase transformation from B19’ martensite to B2 austenite, revealing marginal ∼1.5 ˚C reductions in the active austenite finish (Af) temperature as laser power was increased from 10 W to 60 W. Lastly, long-pulse laser processing results in notable ∼15 ˚C shifts in the austenite start (As) temperature during the reverse martensite phase transformation from B19’→R→B2.

COMPARATIVE EXPERIMENTAL INVESTIGATION ON VISCOSITY AND STABILITY OF W/EG-BASED NON-NEWTONIAN HYBRID NANOFLUIDS

This research explores the stability and rheological characteristics of hybrid nanofluids made from water-ethylene glycol (W/EG) and incorporating nanoparticles such as SiC, Al&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt;, and multi-walled carbon nanotubes (MWCNT). The preparation involved a two-step method, and the nanoparticles were characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM). Stability assessment showed that Al&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt;-MWCNT hybrid nanofluids are optically more stable than SiC-MWCNT as W/EG-based Al&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt;-MWCNT hybrid nanofluids took longer to sediment. Al&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt;-MWCNT hybrid nanofluids exhibited superior stability in visual tests over a period of 19-21 days while SiC-MWCNT nanofluid took 12-14 days to sediment. The rheological analysis revealed that higher particle concentrations resulted in increased viscosity, with SiC-MWCNT and Al&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt;-MWCNT hybrid nanofluids showing viscosity increases of 3.56 and 3.98 times, respectively, in comparison to the base fluid. Conversely, raising the temperature from 25&amp;deg;C to 55&amp;deg;C led to a decrease in shear stress, with reductions of 72.8&amp;#37; and 64.8&amp;#37; observed for SiC-MWCNT and Al&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt;-MWCNT hybrid nanofluids, respectively. Furthermore, the viscosity versus shear rate trends indicated a pseudoplastic or shear-thinning nature for both hybrid nanofluids with particle volume fraction above or equal to 0.1&amp;#37;.

ENSURING THE WORLD-CLASS TACTICAL AND TECHNICAL CHARACTERISTICS OF COMBAT ARMORED VEHICLES BY SUBSTANTIATING THE DESIGN AND TECHNOLOGICAL SOLUTIONS FOR ELEMENTS OF LOADING MECHANISMS: BASIC APPROACHES AND MODELS

The work is aimed at ensuring high tactical and technical characteristics of domestic armored combat vehicles by increasing the contact strength of the most critical and loaded elements of the charging mechanisms. This is due to the fact that due to the conditions of combat operations in modern conditions, the load on these elements of armored combat vehicles is sharply increasing. In such conditions, traditional methods for calculating the contact strength of these elements by conditional stresses with correction factors are not applicable. Therefore, in the course of research, we improved the models of contact interaction based on the development of the theory of variational inequalities. This model includes both variable and sought-after modifications of the shape of the working surfaces of the contacting elements of armored combat vehicles and the properties of the materials of the surface layers. A search for progressive design and technological solutions for these elements has been carried out. This makes it possible to develop a new generation of charging mechanisms that allow for an increase in the caliber of weapon projectiles and the rate of fire from advanced standard weapons. Such advanced solutions make it possible to ensure the tactical and technical characteristics of domestic advanced armored combat vehicles at the world level. The regularities of the influence of the varied parameters (geometric shape and properties of surface layers) on the contact strength of the elements of the charging mechanisms of armored combat vehicles are established. In particular, a significant asymmetry of the area of contact interaction between rollers and drive sprockets was found. This effect is caused by the general deformation, first of all, of the rollers. In this case, the contact area is shifted to the periphery of the working surface. Accordingly, the modification of this working surface (the formation of a “barrel”) has a positive effect on the load capacity of the contacting elements. The levels of contact pressure and equivalent Mises stresses decrease.

Autoantibodies, Oxidative Stress, and Nutritional State in Anorexia Nervosa.

Background/Objectives: Anorexia nervosa (AN) is a complex psychiatric disorder characterized by an extreme fear of gaining weight, leading to severe calorie restriction and weight loss. Beyond its psychiatric challenges, AN has significant physical consequences affecting multiple organ systems. Recent research has increasingly focused on the interplay between autoantibodies, oxidative stress, and nutritional state in this condition. Methods: Ninety-six subjects were evaluated: forty-eight with AN and forty-eight normal-weight control subjects. The serum levels of IgG reactive to hypothalamic antigens, uric acid, and total antioxidant capacity were evaluated by laboratory assays. Results: Anti-hypothalamic autoantibodies were found in AN patients. Furthermore, increased levels of oxidative stress were reported, as measured by decreased serum uric acid and total antioxidant capacity (TAC), and they reduced with the disease duration and the restoration of body mass index (BMI). Finally, a decrease in both autoantibodies and oxidative stress was observed as patients' clinical condition improved, as measured by time since diagnosis and BMI recovery. Conclusions: The clinical improvement of AN patients seems to be associated with a decrease in the autoimmune response to hypothalamic cellular antigens and a reduction in oxidative stress. Dysregulation of the immune system and oxidative stress appear to be interconnected in various diseases, including autoimmune and psychiatric disorders. These findings, although preliminary, may offer potential avenues for the treatment of this challenging condition.