Search Results (850)

Freezing and thawing cycles significantly affect the mechanical and hydraulic behavior of soils, posing detrimental challenges for infrastructures in cold climates. This study develops and validates a coupled Thermal–Hydraulic–Mechanical (THM) model using COMSOL Multiphysics (Version 6.3) to demonstrate the complexities of vapor and water flux, heat transport, frost heave, and vertical stress build-up in unsaturated soils. The analysis focuses on fine sand, sandy clay, and silty clay by examining their varying susceptibilities to frost action. Silty clay generated the highest amount of frost heave and steepest vertical stress gradients due to its high-water retention and strong capillary forces. Fine sand, on the other hand, produced a minimal amount of frost heave and a polarized vertical stress distribution. The study also revealed that vapor flux is more noticeable in freezing fine sand, while silty clay produces the greatest water flux between the frozen and unfrozen zones. The study also assesses the impact of soil properties including the saturated hydraulic conductivity, the particle thermal conductivity, and particle heat capacity on the frost-induced phenomena. Findings show that reducing the saturated hydraulic conductivity has a greater impact on mitigating frost heave than other variations in thermal properties. Silty clay is most affected by these changes, particularly near the soil surface, while fine sand shows less noticeable responses. Full article

Global climate change is causing increasing fluctuations in winter temperatures, including episodes of warm conditions above 9 °C. Such events disrupt cold acclimation in plants and can induce deacclimation, reducing frost tolerance and altering, among other things, hormonal regulation. This study investigated hormonal and molecular changes associated with cold acclimation and deacclimation in oilseed rape (Brassica napus L.) cultivars Kuga and Thure. Plants were grown under different conditions: non-acclimated (17 °C for three weeks), cold-acclimated (4 °C for three weeks), and deacclimated (16/9 °C day/night for one week). Detailed hormone analysis included auxins, gibberellins, cytokinins, stress-related hormones, and the expression of hormone-related genes (BnABF2, BnAOS, BnARF1, BnARR6, BnICS1, BnRGA, and BnWRKY57). Hormone concentrations in leaves changed dynamically in response to deacclimation with increased amounts of growth-promoting hormones and decreased amounts of stress hormones. Additionally, alterations in gene expression during deacclimation, such as in BnABF2 and BnICS1, may function as protective mechanisms to help maintain or regain frost tolerance during reacclimation when temperatures decline again after the warm period. These findings improve the understanding of hormonal and molecular responses involved in the deacclimation of oilseed rape. Full article

Prolactin is a hormone with demonstrated roles in the brain, including neurogenesis, neuroprotection, learning, stress response or memory consolidation. To determine the prolactin expression in the rat hippocampus during aging and to resolve some controversies related to the presence of prolactin in the hippocampus, the aim of this study was to analyze whether changes occur in the expression of prolactin during different stages of life. To determine this, we designed an experimental study in which we analyzed the expression and location of prolactin in the rat hippocampus, Ammon’s horn and Dentate Gyrus, during different stages of life (prepubertal, postpubertal, young adult, adult and old) and checked if there are differences related to sex. Overall, the results obtained show that prolactin is present in the rat hippocampus and that prolactin is synthesized, as deduced from the findings obtained via ELISA, immunohistochemistry, qPCR and in situ hybridization. After analyzing the correlation between serum and hippocampal prolactin levels and comparing the amounts of Prl mRNA and the hormone, the results obtained suggest that hippocampal prolactin has a dual origin: local synthesis of the hormone and its passage from the blood. On the other hand, the amounts of prolactin and its mRNA in the hippocampus vary with sex and age, suggesting the existence of age-related sexual dimorphism. The results obtained suggest that hippocampal aging is related to a decrease in the hippocampal prolactin system, which helps to better understand brain aging. Full article

Molasses, a by-product of raw sugar production, is widely used as a cost-effective carbon and nutrient source for industrial fermentations, including the production of baker’s yeast (Saccharomyces cerevisiae). Due to the cost and limited availability of molasses, efforts have been made to replace molasses with cheaper and more readily available substrates such as corn syrup. However, the quality of dry yeast drops following the replacement of molasses with corn syrup, despite the same amount of total sugar being provided. Our understanding of how molasses replacement affects yeast physiology, especially during the dehydration step, is limited. Here, we examined changes in gene expression of a strain of baker’s yeast during fermentation with increasing corn syrup to molasses ratios at the transcriptomic level. Our findings revealed that the limited availability of the key metal ions copper, iron, and zinc, as well as sulfur from corn syrup (i) reduced their intracellular storage, (ii) impaired the synthesis of unsaturated fatty acids and ergosterol, as evidenced by the decreasing proportions of these important membrane components with higher proportions of corn syrup, and (iii) inactivated oxidative stress response enzymes. Taken together, the molecular and metabolic changes observed suggest a potential reduction in nutrient reserves for fermentation and a possible compromise in cell viability during the drying process, which may ultimately impact the quality of the final dry yeast product. These findings emphasize the importance of precise nutrient supplementation when substituting molasses with cheaper substrates. Full article

Plastic pollution has recently become a serious environmental problem, since the continuous increase in plastic production and use has generated enormous amounts of plastic waste that decomposes to form micro- and nanoparticles (MPs/NPs). Recent evidence suggests that nanoplastics may be potent toxins because they are able to freely cross biological barriers, posing health risks, particularly to developing organisms. Therefore, the aim of the current study was to investigate the toxic potential of polystyrene nanoparticles (PS-NPs) on the jejunum of immature rats. Two-week-old animals were orally exposed to environmentally relevant dose of small PS-NPs (1 mg/kg b.w.; 25 nm) for 3 weeks. We detected a significant accumulation of PS-NPs in the epithelium and subepithelial layer of the intestine, which resulted in significant changes in the expression of genes related to gut barrier integrity, nutrient absorption, and endocrine function. Moreover, increased expression of proinflammatory cytokines was observed together with decreased antioxidant capacity and increased markers of oxidative damage to proteins. Additionally, in the jejunal extracts of exposed rats, we also noted changes in the metabolite profile, mainly amino acids involved in molecular pathways related to cellular energy, inflammation, the intestinal barrier, and protein synthesis, which were consistent with the observed molecular markers of inflammation and oxidative stress. Taken together, the results of the metabolomic, molecular, and biochemical analyses indicate that prolonged exposure to PS-NPs may disrupt the proper function of the intestine of developing organisms. Full article

Cardiomyocytes, similarly to cells in various tissues, are responsive to mechanical stress of all types, which is reflected in the significant alterations to their electrophysiological characteristics. This phenomenon, known as mechanoelectric feedback, is based on the work of mechanically gated channels (MGCs) and mechano-sensitive channels (MSCs). Since microgravity (MG) in space, as well as simulated microgravity (SMG), changes the morphological and physiological properties of the heart, it was assumed that this result would be associated with a change in the expression of genes encoding MGCs and MSCs, leading to a change in the synthesis of channel proteins and, ultimately, a change in channel currents during cell stretching. In isolated ventricular cardiomyocytes of rats exposed to SMG for 14 days, the amount of MGCs and MSCs gene transcripts was studied using the RNA sequencing method by normalizing the amount of “raw” reads using the Transcripts Per Kilobase Million (TPM) method. Changes in the level of channel protein, using the example of the MGCs TRPM7, were assessed by the Western blot method, and changes in membrane ion currents in the control and during cardiomyocyte stretching were assessed by the patch-clamp method in the whole-cell configuration. The data obtained demonstrate that SMG results in a multidirectional change in the expression of genes encoding various MGCs and MSCs. At the same time, a decrease in the TPM of the MGCs TRPM7 gene leads to a decrease in the amount of TRPM7 protein. The resulting redistribution in the synthesis of most channel proteins leads to a marked decrease in the sensitivity of the current through MGCs to cell stretching and, ultimately, to a change in the functioning of the heart. Full article

Rock bursts usually happen during the hours or days after tunnel excavation, even in an unsupported opening where no collapses occur. To investigate the mechanism of those delayed failures in brittle rock tunnels, this paper showcases the performed scale-model test based upon the Jinping II headrace tunnelling project. The model test was conducted in a particularly designed loading apparatus; the scale-model is composed of a similar material for the deep brittle rock. The tunnel in the scale-model is excavated by a specially made drilling tool. The failure mode of the deep circle tunnel under isotropic and anisotropic geostress were obtained; the delay failure time was recorded, and the accompanying stresses and strains changing were monitored. Under isotropic geostress the failure shape has a smooth circle boundary, failure process totally costs 56 h. While under anisotropic geostress a dog-eared breakdown was found, the failure process amounted to 72 h. The time-to-failure was evaluated by delay failure theory, and the evaluation equation was implemented into in FEM code. Numerical simulations have been performed to simulate the failure time and failure mode. The numerical results of failure time and failure mode mainly match the scale-model testing results. Full article

With the development of technology, an increasing amount of literature regarding the expression profiles and physiological functions of Prxs has been published. Despite this growing interest, there is currently no systematic review of expression profiles in different insects. Here, we performed a systematic review of the available literature on the location and expression of Prxs in different tissues, developmental stages and sexes in insects. Recent studies on the structure, expression profiles and functional characterization of Prxs provide valuable insights into the molecular mechanisms and functional pathways of this important enzyme family. In insects, Prxs are crucial for antioxidant defense, development, stress adaptation, cell apoptosis, immune response and insecticide resistance. This systematic review provides an overview of the various functions of Prxs as reported in the literature and highlights that many environmental stresses induce changes in Prxs expression levels. Furthermore, we present perspectives on future research directions regarding insect Prxs and discuss their potential applications in pest control. Full article

Background: Diabetics accumulate Advanced Glycation End products (AGEs) such as Nε-(carboxymethyl)lysine (CML) in their skin, which can provoke changes in the skin’s biomechanical properties. The same changes are also observed during aging. Collagen is one of the first targets of glycation, and this leads to the disruption of the dermis, potentially contributing to the skin complications seen in diabetes, like impaired wound healing and the formation of chronic ulcers. We therefore investigated whether it was possible to detect differences in the biomechanical properties of the reticular dermis by comparing C57/BL6 control mice, type 1 and type 2 diabetic mice, and aged mice. Methods: To investigate this, we used an Atomic Force Microscope (a type of local probe microscope used to visualize the surface topography of a sample) to measure the elastic modulus of each skin sample. The elastic modulus is a parameter that describes a tissue’s resistance to elastic deformation when stress is applied. We also determined whether diabetes is associated with the accumulation of AGEs via Western blots. Results: We found that type 2 diabetic mice and aged mice had a stiffer reticular dermis than young control mice. No differences were found in type 1 diabetic mice. The results of the Western blot did not reveal any significant differences in the CML content in different types of mice, although a non-significant increase was found in type 2 diabetic and aged mice. We show that there is a significant positive correlation between the amount of CML in a mouse and the rigidity of its reticular dermis. Conclusions/interpretation: We have demonstrated that increased glycation in mouse skin is correlated with the biomechanical properties of that skin, which explains the wound healing defects diabetic patient’s experience. AFM is therefore a powerful technique that could be used to characterize the mechanical effects of treatments aimed at reducing the level of AGEs in the skin. Full article

To investigate the interaction effects of resting times (0, 6, and 12 h) and NaHCO₃ concentrations (0, 2, 4, and 6 g/kg) on chicken myofibrillar protein (CMP), this study analyzed the changes in solubility, active sulfhydryl groups, rheological behavior, fluorescence, and gel properties of CMP solutions (60 mg/mL). The results indicated that pH significantly increased with higher NaHCO₃ concentrations and longer resting times. Consequently, solubility, active sulfhydryl groups, apparent viscosity, shear stress, G’ value at 80 °C, hardness, springiness, and cohesiveness all significantly increased, while particle size, turbidity, and whiteness significantly decreased. However, these trends were not observed in samples treated with an amount of 6 g/kg NaHCO₃ and/or a resting time of 12 h. The findings suggest that treatment with 4 g/kg NaHCO₃ and a resting time of 6 h effectively reduced protein aggregation and enhanced solubility. Conversely, excessive NaHCO₃ or prolonged resting times resulted in decreased protein solubility and deteriorated textural properties. Full article

Early detection of plant water status is crucial for efficient crop management. In this research, proximal sensing tools (i.e., hyperspectral imaging HSI and thermal IR camera) were used to monitor changes in spectral and thermal profiles of a citrus orchard in Sicily (Italy), managed under five irrigation systems. The irrigation systems differ in the amount of water distribution and allow four different strategies of deficit irrigation to be obtained. The physiological traits, stem water potential, net photosynthetic rate, stomatal conductance and the amount of leaf chlorophyll were measured over the crop’s growing season for each treatment. The proximal sensing data consisted of thermal and hyperspectral imagery acquired in June–September during the irrigation seasons 2023–2024 and 2024–2025. Significant variation in physiological traits was observed in relation to the different irrigation strategies, highlighting the highest plant water stress in July, in particular for the partial root-zone drying irrigation system. The water-use efficiency (WUE) values in subsurface drip irrigation were similar to the moderate deficit irrigation treatment and more efficient (up to 50%) as compared to control. Proximal sensing measures confirmed a different plant water status in relation to the five different irrigations strategies. Moreover, four spectral indices (Normalized Difference Vegetation Index NDVI; Water Index WI; Photochemical Reflectance Index PRI; Transformed Chlorophyll Absorption Ratio Index TCARI), calculated from HSI spectra, highlighted strong correlations with physiological traits, especially with stem water potential and the amount of leaf chlorophyll (coefficient of correlation ranged between −0.4 and −0.5). This study demonstrated the effectiveness of using proximal sensing tools in precision agriculture and ecosystem monitoring, helping to ensure optimal plant health and water use efficiency. Full article

The Tankou area is a vital production capacity replacement area in the Jianghan oilfield. The recovery of the amount of erosion in Qianjiang Formation and Jinghezhen Formation is significant for studying this area’s tectonic evolution and geothermal history. The target layer, characterised by well-developed plastic materials, intense tectonic deformation, and insufficient well data, fails to meet the applicability criteria of the conventional denudation estimation methods. This study proposes a novel approach based on the structural strain characteristics. The method estimates the stratigraphic denudation by analysing residual formation features and fault characteristics. First, a stress analysis is performed using the fault characteristics, and the change law for the thickness of the target layer is summarised based on the characteristics of the residual strata to recover the amount of erosion in the profile. Second, a grid of the stratigraphic lines in the profiles of the main line and the tie line is used to complete the recovery of the amount of erosion in the plane through interpolation, and the results of the profile recovery are corrected again. Finally, the evolution results of the geological equilibrium method and the stress–strain analysis are compared to analyse the reasonableness of their differences and verify the accuracy of the erosion recovery results. The area of erosion in each layer increases from bottom to top. The amount of denudation in each layer gradually increases from the denudation area near the southern slope to the surrounding area. It converges to 0 at the boundary of the denudation area. The maximum amount of erosion is distributed in the erosion area close to the side of the residual layer with a low dip angle. The specific denudation results are as follows: Qian1 Member + Jinghezhen Formation has a denudation area of 6.3 km² with a maximum denudation thickness of 551 m; Qian2 Member has a denudation area of 2.6 km² with a maximum denudation thickness of 164 m; Qian3 Member has a denudation area of 2.3 km² with a maximum denudation thickness of 215 m; Upper Qian4 Submember has a denudation area of 1.54 km² with a maximum denudation thickness of 191 m; and Lower Qian4 Submember has a denudation area of 1.2 km² with a maximum denudation thickness of 286 m. This method overcomes the conventional denudation restoration approaches’ reliance on well logging and geochemical parameters. Using only seismic interpretation results, it achieves relatively accurate denudation restoration in the study area, thereby providing reliable data for timely analyses of the tectonic evolution, sedimentary facies, and hydrocarbon distribution patterns. In particular, the fault displacement characteristics can be employed to promptly examine how reasonable the results on the amount of denudation between faults are during the denudation restoration process. Full article

The extracellular matrix (ECM) provides structural support to cells, thereby forming a functional tissue. In cancer, the growth of the tumor creates internal mechanical stress, which, together with the remodeling activity of tumor cells and fibroblasts, alters the ECM structure, leading to an increased stiffness of the pathological ECM. The enhanced ECM stiffness, in turn, stimulates tumor growth and activates tumor-promoting fibroblasts and tumor cell migration, leading to metastasis and increased therapy resistance. While the relationship between matrix stiffness and migration has been studied before, their connection to internal tumor stress remains unresolved. Here we used 3D ECM-embedded spheroids and hydrogel particle stress sensors to quantify and correlate internal tumor spheroid pressure, ECM stiffness, ECM remodeling, and tumor cell migration. We note that 4T1 breast cancer spheroids and SV80 fibroblast spheroids showed increased invasion—described by area, complexity, number of branches, and branch area—in a stiffer, cross-linked ECM. On the other hand, changing ECM stiffness only minimally changed the radial alignment of fibers but highly changed the amount of fibers. For both cell types, the pressure measured in spheroids gradually decreased as the distance into the ECM increased. For 4T1 spheroids, increased ECM stiffness resulted in a further reach of mechanical stress into the ECM, which, together with the invasive phenotype, was reduced by inhibition of ROCK-mediated contractility. By contrast, such correlation between ECM stiffness and stress-reach was not observed for SV80 spheroids. Our findings connect ECM stiffness with tumor invasion, ECM remodeling, and the reach of tumor-induced mechanical stress into the ECM. Such mechanical connections between tumor and ECM are expected to drive early steps in cancer metastasis. Full article

Eggs are a great source of protein in the human diet. They are consumed in tens of millions of tons globally per year. In addition, egg proteins, which are known food allergens, are included in many food products due to their excellent techno-functional properties. Hen’s eggs are the most consumed, but other edible avian eggs are occasionally used as gourmet ingredients or delicacies. With a high presence in the food market, the risk of accidental exposure to egg allergens is high. Hen egg allergy ranks among the top three food allergens in infants and young children. The complex structure and similar physicochemical properties of egg proteins limit their separation and purification, making further research challenging. Egg composition is influenced by age, disease, medicine, and environmental stress, and the target protein is often present in negligible amounts or polymorphic forms. To investigate the immunoreactivity of proteins from eggs of different bird species, it is necessary to consistently and quantitatively extract and purify proteins while avoiding harsh conditions. The conformational shape of allergens is impacted by denaturation, which can remove or expose IgE-binding epitopes and change the allergenic potential of proteins. This review presents findings from a literature survey on the isolation and purification strategies utilized for egg allergens from culinary-relevant bird eggs. Full article

During the heat treatment of stainless steel (SS)/carbon steel (CS) bimetal composites, the carbon in the CS diffuses into the SS, and carbides precipitate on the grain boundary and in the grains, affecting the microstructure and properties of the composite steel. In order to change the precipitation and distribution of the carbides seen on hot-rolled 304/Q235 after cold drawing (HR), the microstructure and properties of composite round steel were investigated by optical microscopy, SEM/EDS, and hardness, tensile, fatigue, and electrochemical tests while changing the temperature of the full annealing and aging treatments. The results showed that dispersed chromium carbide particles precipitated at the grain boundaries, and intragranular and slip lines promoted simultaneous dispersion strengthening and fine-grain strengthening and greatly improved the hardness, yield strength, tensile strength, and fatigue strength of the composite round steel. However, the increase in chromium carbide particles leads to the formation of stress concentration points and accelerates the creation of fatigue cracks, resulting in a decrease in the fatigue strength of the steel. Simultaneously, the corrosion resistance of the composite round steel samples was reduced due to the precipitation of a large amount of chromium carbide. Full article