Search Results (349)

Background: Neuroinflammation and gut–brain axis (GBX) dysregulation are key pathological drivers of stress-related neuropsychiatric disorders. Zhi-Zi-Chi Decoction (ZZCD), a classic Traditional Chinese Medicine (TCM) formula, has been clinically used to alleviate mental disturbances via the TCM principle of “clearing heat and relieving restlessness.” Still, its modern neuroprotective mechanisms, especially its links to gut microbiota and central signaling pathways, remain incompletely elucidated. Purpose: This study aimed to systematically investigate the therapeutic effects of ZZCD on chronic restraint stress (CRS)-induced neurodysfunction in mice and clarify its mechanisms from the perspectives of TCM theory, material basis, gut microbiota–metabolite axis, and central signaling pathways. Method: CRS mice were treated with ZZCD or protocatechuic acid. Behavioral tests evaluated depression- and anxiety-like behaviors. UHPLC-Q-TOF/MS identified ZZCD’s chemical constituents; 16S rRNA sequencing and untargeted metabolomics analyzed gut microbiota and metabolite changes. Western blot, immunofluorescence, and proteomics examined neuroinflammation, microglial polarization, and signaling pathway activity (PI3K/Akt/mTOR, AMPK). Results: ZZCD reversed CRS-induced depression- and anxiety-like behaviors and suppressed neuroinflammation. Mechanistically, UHPLC-Q-TOF/MS identified 424 ZZCD constituents, with prenol lipids, organooxygen compounds, and flavonoids as the most abundant. ZZCD reversed CRS-induced imbalance in gut microbiota, reducing pro-inflammatory Prevotella and enriching beneficial Lactobacillus, and mediated the enrichment of the prebiotic metabolite PCA in colonic and serum samples, which crossed the blood–brain barrier (BBB) to exert neuroprotection. Additionally, ZZCD and PCA normalized the PI3K/Akt/mTOR pathway and activated AMPK, promoting M2 microglial polarization and restoring synaptic plasticity. Conclusions: ZZCD exerts antidepressant effects by a gut-microbiota-dependent modulation of PCA-PI3K/Akt/mTOR and AMPK dual axes that converts microglia from M1 to M2, providing ethnopharmacological evidence and a mechanistic rationale for its clinical application in major depressive disorder. Full article

Ganoderma lucidum is a medicinal fungus widely utilized in traditional medicine and functional foods. Its primary bioactive constituents are ganoderic acids (GAs), a group of triterpenoid compounds. While chemical-induced apoptosis has previously been shown to enhance GAs production, this study investigates the role of physical stress in this regulatory pathway. We demonstrate that heat-induced apoptosis significantly increases GAs production in G. lucidum. To determine whether apoptosis directly regulates this process, we overexpressed the human anti-apoptotic gene Bcl-2 in G. lucidum, confirming expression via RT-PCR and Western blot analysis. Upon heat-induced apoptosis, these Bcl-2 overexpression mutants exhibited increased mycelial cell viability, accompanied by reduced metacaspase activity and, notably, decreased GAs production. Furthermore, we identified a Type I metacaspase gene in G. lucidum, Glmca1, which contains highly conserved catalytic domains common across fungal species. Silencing of Glmca1 followed by heat-induced apoptosis led to results similar to Bcl-2 overexpression: enhanced cell viability, suppressed metacaspase activity, and a significant reduction in GAs yield. These findings provide compelling evidence that apoptosis functions as a critical regulatory mechanism for secondary metabolite production in G. lucidum. Consequently, modulating apoptotic pathways through physical induction offers a promising strategy for enhancing the production of bioactive ingredients in medicinal fungi. Full article

(1) Background: Variations in bean temperature before grinding are a little-studied factor, but they can potentially influence the characteristics of the resulting powder and the chemical and physical properties of the espresso beverage. This study investigated the effect of two heat treatments, heating and cooling, applied to coffee beans immediately before grinding. (2) Methods: The analyses focused on powder particle size distribution (laser diffraction), impact on the operation of the coffee grinder (noise and electrical absorption), chemical-physical properties of the beverage, caffeine and chlorogenic acid content (HPLC-DAD) and profile of volatile organic compounds (HS-SPME-GC-MS). (3) Results: Heating induced a decrease in the content of caffeine and chlorogenic acids and a change in the aromatic profile consistent with phenomena like accelerated aging (increase in hexanal). Cooling treatment had similar, but less pronounced, effects, although it reduced caffeine extraction and some aromatic compounds. (4) Conclusions: The study demonstrated that the temperature of the coffee beans prior to grinding is a key factor to consider in terms of the particle size distribution of the resulting coffee grounds, as well as the content of bioactive compounds and volatile organic compounds, which can significantly influence various aspects of the final espresso’s quality. Full article

This review examines sorghum digestibility from molecular structure to clinical implications, focusing on compositional factors, processing methods, and health outcomes. We evaluate how sorghum’s unique protein–starch interactions influence digestibility and explore emerging technologies that can modulate these properties for targeted nutritional benefits. Cooked sorghum generally has lower digestibility than raw sorghum and other cereals due to heat-induced protein–starch cross-linking and the formation of disulfide bonds by sorghum proteins (kafirins), which restrict enzymatic access. Enzyme inhibitors in sorghum further reduce starch hydrolysis. This reduced digestibility may negatively impact malnourished individuals and those relying on sorghum as a dietary staple. However, it can be advantageous to individuals with diabetes by lowering postprandial blood glucose levels. Sorghum consumption may also beneficially influence the gut microbiome. Certain processing methods have been shown to significantly enhance digestibility while preserving beneficial bioactive compounds. Improving digestibility through these strategies may enhance sorghum’s value for vulnerable populations while maintaining its metabolic advantages. Balancing increased nutrient bioavailability with preservation of beneficial functional properties is critical for optimizing sorghum as a health-promoting grain across diverse populations. Full article

Background/Objectives: Achillea millefolium is a well-known medicinal plant recognized in several pharmacopeias, while the Balkan endemic species Achillea clypeolata lacks a pharmacopeial monograph and remains insufficiently studied despite its traditional use. This study aimed to comparatively evaluate the phytochemical composition and biological potential of both species. Methods: Chemical composition was studied using UHPLC-MS/MS, HPLC, and FT-IR; anti-inflammatory potential was analyzed by erythrocyte membrane stabilization assay (heat- and hypotonicity-induced hemolysis); and enzyme-inhibitory activity was tested against collagenase, elastase, hyaluronidase, and tyrosinase. In addition, antioxidant activity was evaluated using DPPH, ABTS, and DCFDA assays; antimicrobial activity was determined using the broth microdilution method; and cytotoxic potential was investigated by the MTT assay. Results: The major constituents in water–ethanolic extracts were quinic acid derivatives, flavonoids, phenolic acids, and coumarins, with chlorogenic acid, 3,5-dicaffeoylquinic acid, cosmosiin, cynaroside, rutin, and hyperoside as dominant in both species. Extracts exhibited marked anti-inflammatory activity, where A. millefolium provided greater protection under heat-induced hemolysis, and both extracts showed comparable efficacy under osmotic stress. Concentration-dependent inhibition of collagenase, elastase, hyaluronidase, and tyrosinase (concentration from 62.5 to 1000 µg/mL), along with significant antioxidant activity in ABTS and DPPH assays, was observed. In MRC-5 cells, the extracts reduced AAPH-induced ROS levels up to 50 µg/mL, while higher concentrations showed diminished effects. Moderate cytotoxicity was observed, with A. clypeolata displaying stronger effects at 50–100 µg/mL. Both Achillea species exhibited broad-spectrum antimicrobial activity, with pronounced effects against Gram-positive bacteria. Conclusions: The results support the traditional use of Achillea species and highlight A. clypeolata as a promising, yet underexplored, source of bioactive compounds for dermatological and pharmaceutical applications. Full article

Aiming at the urgent heat dissipation demands of high-power, high-integration electronic devices, Cu/Al composite heat sinks combine the high thermal conductivity of copper and the lightweight advantage of aluminum, becoming a mainstream solution for advanced thermal management systems. The significant physicochemical differences between Cu and Al, however, make high-quality joining a technical bottleneck. In this study, flux-free ultrasonic brazing with a Zn-based filler metal was used to join 6061 aluminum alloy and industrial pure copper. Gradient heat treatment (55–300 °C) was subsequently applied to systematically investigate its effect on the microstructure, microhardness, and thermal properties of the joints. The results show that the as-brazed joint exhibited excellent bonding (97.3% bonding rate) and shear strength (95.24 MPa). The weld seam consisted of Zn solid solution, Cu solid solution, and Al-Cu-Zn ternary compounds. Heat treatment did not induce new phases but led to the coarsening of Zn-Al-Cu compounds and aggregation of the eutectic structure, reducing grain boundaries. Consequently, the microhardness at the weld center varied non-monotonically, and the thermal conductivity of the joint showed an overall increasing trend with rising heat treatment temperature. This enhancement is attributed to reduced phonon scattering at diminished grain boundaries. This study clarifies the heat treatment–microstructure–thermal properties relationship, providing important guidance for the thermal performance optimization of Cu/Al composite heat sinks. Full article

The effect of treatment time on arc-enhanced glow discharge plasma-assisted nitriding (AEGD-PAN) of AISI M2 high-speed steel was investigated for non-heat-treated and heat-treated substrates. Nitriding treatments were carried out at 350 °C for 1.5 and 3.5 h, producing diffusion layers with thicknesses ranging from approximately 38 to 75 µm without formation of a continuous brittle compound layer. X-ray diffraction combined with Rietveld refinement revealed the progressive formation of γ′-Fe₄N and ε-Fe₂₃N nitrides together with lattice expansion of the α-Fe matrix, indicating nitrogen supersaturation and precipitation strengthening within the diffusion zone. Heat-treated specimens exhibited higher surface hardness, reaching ~1350 HV_0.1, while non-heat-treated substrates developed pronounced hardness gradients associated with diffusion-controlled layer growth. Scratch testing showed improved resistance to contact-induced damage with increasing nitriding time, particularly for the 3.5 h treatment, where lateral cracking was significantly reduced and load-bearing capacity increased. Multi-pass scratch wear tests revealed a reduction in the Archard wear coefficient by up to four orders of magnitude compared with untreated M2 steel. These results demonstrate that AEGD-PAN at moderate temperature enables efficient diffusion layer formation and significant improvement in the tribological performance of high-alloy tool steels. Full article

Watermelon juice is a nutritious yet highly perishable beverage. Conventional thermal pasteurization ensures safety but degrades heat-sensitive nutrients, color, and flavor. Induced electric field (IEF) is an emerging technology that inactivates microorganisms while better preserving quality. However, its effects on the comprehensive quality retention of watermelon juice during storage remain underexplored. This study investigated the efficacy of IEF treatment on the microbial inactivation and quality preservation of watermelon juice during 25 days of storage at 4 °C. Freshly extracted watermelon juice was subjected to low-temperature IEF at 65 °C (IEF1) for 101 s and 60 °C (IEF2) for 88 s, with conventional pasteurization (65 °C, 30 min) as a control. The results showed that no colonies were detected in the IEF2 group throughout the 25-day storage period. Both IEF treatment and pasteurization effectively inhibited juice acidification. Soluble solids content and electrical conductivity remained stable under refrigeration, and the IEF group showed slower and more controllable acidity on day 25. Notably, the IEF1 group retained the highest lycopene content at the end of storage, while the IEF2 group maintained the highest total phenolic content (TPC). Furthermore, IEF treatment effectively mitigated color deterioration and preserved carbohydrate stability during refrigeration. Flavor analysis revealed that the taste profile of the IEF2 group at the initial storage stage closely resembled that of fresh watermelon juice. Over the 25-day period, the relative content of key volatile compounds characteristic of fresh watermelon decreased by only 3.64% in the IEF2 group. Full article

A three-dimensional steady-state thermomechanical contact formulation based on the Boundary Element Method is presented for the analysis of systems involving internal linear heat sources. The formulation consistently couples thermal conduction and thermoelastic contact effects within a boundary integral framework and is suitable for layered configurations governed by interface interactions. The approach is first validated through benchmark problems and subsequently applied to the analysis of a radiant floor system composed of a self-levelling compound and a surface floor covering supported by an elastic foundation. Linear heat sources representative of heating pipes are embedded within the compound layer, and the influence of their vertical position on the thermal and mechanical response of the system is investigated. The results show that the mean surface temperature exhibits an approximately linear dependence on the depth of the heat sources, indicating a high sensitivity of the thermal response to installation parameters. An extended scenario accounting for constrained displacements at the upper edge is also analysed in order to represent more realistic boundary conditions. Under these conditions, partial interface separation induced by thermal expansion leads to a reduction in the heat transferred towards the surface and to lower surface temperature levels. The proposed formulation provides a physically consistent and efficient framework for the analysis of thermomechanical contact problems with localized heat sources, offering an alternative tool for the investigation of layered floor systems and related engineering applications. Full article

Shot-hole disease caused by Wilsonomyces carpophilus poses a significant threat to stone fruit species, including wild apricot (Prunus armeniaca L.). This study investigated pathogenic factors (cell wall-degrading enzymes and toxins) and metabolites produced by a highly pathogenic strain (CFCC 71544) and a weakly pathogenic strain (CFCC 71543) of W. carpophilus during infection of P. armeniaca (in planta conditions). Analysis using the 3,5-dinitrosalicylic acid colorimetric method revealed that polygalacturonase (CFCC 71544: 1367.02 U/g; CFCC 71543: 1264.00 U/g) and polymethylgalacturonase (CFCC 71544: 1898.71 U·g⁻¹; CFCC 71543: 1762.21 U·g⁻¹) were the most active cell wall-degrading enzymes, with higher activities observed in the highly pathogenic strain (CFCC 71544). Crude toxins from CFCC 71543 induced leaf lesions averaging 41.91 mm² and retained activity after exposure to 121 °C and UV treatment. Non-protein fractions of the toxins caused significantly larger lesions than protein fractions (15.93 mm² vs. 5.56 mm², respectively). Building on these in planta findings, we further characterized toxin properties under controlled laboratory conditions (in vitro). Optimal toxin production conditions were identified in Richard culture medium at pH 4, under a 12 h light/dark cycle, shaken for 12 days at 25 °C. Untargeted metabolomics identified 3244 compounds and 977 differential metabolites among mycelia, crude toxins, and the residual aqueous phase after organic solvent extraction; these metabolites were predominantly amino acids and derivatives and organic acids. These findings indicate that the main pathogenic factors of W. carpophilus are highly active polygalacturonase and heat/UV-stable, water-soluble, non-protein toxins, providing a theoretical basis for shot-hole disease prevention and control. Full article

Quercus suber bark, known as cork, is an important fire-adaptive trait of this Mediterranean species. However, the increased frequency of wildfires and poor forest management practices can be significant challenges in managing the sustainable exploitation of cork oak stands. This study evaluates cork’s thermal behavior and organoleptic quality for commercial applications under three experimental fire scenarios: prescribed burn, low-intensity wildfire, and high-intensity wildfire. Bench-scale tests were conducted using a vertical mass loss calorimeter to simulate heat exposure levels, measuring temperature changes at four cork depths and quantifying heat-induced damage. Morphological traits—cork thickness, corkback thickness, and relative humidity—were recorded as predictor variables. Additionally, organoleptic and aromatic analyses were performed to assess the suitability of fire-exposed cork for wine stopper production. Results were consistent with the available literature, confirming that cork thickness significantly reduces the maximum temperature at the phellogen level. Specifically, mean cork thickness showed a significant negative effect on Tmax4 (β = −0.02, p < 0.001), indicating a consistent decrease in internal temperatures with increasing thickness across all heat flux levels. By contrast, cork consumption (mass loss) was primarily driven by heat flux intensity rather than cork structural traits. Aromatic profiling and organoleptic analysis revealed the presence of smoke-related compounds in cork samples exhibiting external carbonization. This effect was observed under higher heat flux exposure (particularly at 25 and 50 kW m⁻²), where visible charring occurred. Under these conditions, commercial quality may be partially compromised, whereas samples without external carbonization did not show comparable aromatic alteration. Further field validation is recommended. Full article

Climate change-induced abiotic stress, particularly heat and drought during olive oil accumulation, significantly threatens the productivity and oil quality of olive trees (Olea europaea L.). This study investigated the efficacy of pre-harvest elicitation using the biostimulants harpin and chitosan (both as commercially available products) under summer conditions in Greece, in commercially productive rainfed groves of cv. ‘Megaritiki’. Multivariate analysis (PCA and factor analysis) revealed that pre-harvest application of these elicitors successfully balanced the trade-off between oil yield and quality. Both harpin and chitosan maintained hydrolytic (free acidity—0.25 and 0.29 g oleic acid 100 g⁻¹, respectively, compared to 0.56 g oleic acid 100 g⁻¹ in the control) and primary oxidative markers (peroxides—4.16 and 4.16 meq O₂ kg⁻¹, respectively, compared to 5.20 meq O₂ kg⁻¹ in the control) at exceptionally low levels compared to untreated trees. The treatments induced a distinctive metabolic shift regarding volatile compounds governed by the lipoxygenase (LOX) pathway. Harpin application was strongly associated with complex floral and fruity volatile compounds (2-hexen-1-ol and trans-2-hexenal) and a high α-tocopherol concentration (38.58 mg kg⁻¹ compared to 23.12 mg kg⁻¹ in the control), suggesting an enhanced physiological response in favor of oil quality attributes. Conversely, chitosan elevated the oxidative stability of the oil by increasing total phenol concentration (by almost 97% compared to the control) and prioritizing the accumulation of the stable monounsaturated fatty acids (oleic acid—increased by 12.5% compared to the control) over polyunsaturated ones (linoleic acid), while endowing the oil with desirable “green freshness” aromas (cis-3-hexenal). These results demonstrate that elicitation with harpin and chitosan is a potent tool for sustainably enhancing extra virgin olive oil quality under rainfed conditions in Greece, steering fruit metabolism toward a premium nutraceutical and sensory profile and enhancing the functional properties of the oil (phenol content, antioxidant capacity, monounsaturated fatty acids, α-tocopherol and squalene). Full article

This study aimed to evaluate the effects of high-intensity ultrasound (40 W/5 min), applied with and without mild heating (59 °C and 23 °C), and of pasteurization (63 °C/30 min), on the physicochemical, rheological, and microbiological parameters, as well as on ascorbate oxidase activity, total carotenoid content, phenolic compound profile, and antioxidant capacity of passion fruit (Passiflora edulis Sims.) pulps. Ultrasound processing induced changes in color (L*, a*, and b*), resulting in high ∆E values. Following ultrasound treatment, an increase in apparent viscosity at 100 s⁻¹ was observed. Ultrasound also promoted partial inactivation of ascorbate oxidase and a significant reduction in mold and yeast counts. Moreover, the application of ultrasound without heating (US-20) promoted the retention of 55% of ascorbic acid after 63 days of storage. The condition with heating (US-60) led to an increase in catechin content in both bright red passion fruit pulp (173.96%) and yellow passion fruit pulp (5.89%), demonstrating a balance between the retention of bioactive compounds, microbial inactivation, and reduction in ascorbate oxidase activity. Therefore, these results highlight ultrasound as a non-thermal and sustainable technology capable of extending shelf life, maximizing the preservation of bioactive compounds, and enhancing the functional properties of fruit pulps. Full article

Enhancing convective heat transfer in solar air heaters (SAHs) without disproportionate hydraulic penalty remains critical for decentralized low-carbon heating. This study experimentally investigates a serpentine-channel SAH equipped with distributed three-dimensional vortex generators under outdoor winter conditions. The configuration combines curvature-induced secondary motion with distributed vortex generation to intensify absorber–air heat transfer. Experiments were conducted over a mass flow range of 0.012–0.061 kg s⁻¹, corresponding to a Reynolds number range of 2.1 × 10³–1.07 × 10⁴, using a smooth duct as the reference configuration. The enhanced configuration achieved peak thermal efficiencies of 81.6–85.4%, compared with 65.8–67.7% for the smooth collector, while daily averaged efficiency increased from 56–59% to 71–75%. Although pressure drop increased, thermo-hydraulic performance remained superior across the investigated Reynolds number range. Exergy efficiency was consistently higher for the enhanced system and remained within optical limit constraints. Environmental assessment based on grid emission factor displacement indicates approximately 33% greater annual CO₂ mitigation potential, corresponding to about 6.6 tonnes over a 20-year service life. The levelized cost of heating was estimated at 3.1–4.4 ₹ kWh⁻¹. These results indicate that compound curvature–vortex transport intensification can improve thermal efficiency and increase carbon mitigation potential under realistic operating conditions. Full article

Friction stir welding (FSW) is a key technology for manufacturing T-shaped thin-walled structures and avoiding fusion welding defects. However, the quantitative relationship between its process parameters and the microstructure properties of the joint remains unclear. To address this, this study established regression models via response surface methodology (RSM) relating rotational speed (w), welding speed (v), and plunge depth (h) to the mechanical properties of T-joints. The optimal process parameters (400 rpm, 60 mm/min, 0.21 mm) were determined, under which the ultimate tensile strength (UTS) and weld nugget hardness (WNH) of the joint reached 74.1% (377 MPa) and 94.4% (153 Hv) of the base materials (BM) respectively, with v showing the most significant influence on joint mechanical properties. Microstructural observations revealed that from the BM to the stirring zone (SZ), the grains underwent a continuous evolution from coarsening, partial recrystallization to complete dynamic recrystallization (DRX). In the SZ, due to severe plastic deformation and high heat input, the continuous dynamic recrystallization (CDRX) was the dominant mechanism, and the grain was significantly refined. The heat input in the thermomechanical affected zone (TMAZ) is relatively low, mainly geometric dynamic recrystallization (GDRX). DRX-driven grain refinement was the primary strengthening factor in the joint, with hardness closely related to grain size. However, thermal cycling induced softening in the heat-affected zone (HAZ) and promoted the precipitation of brittle compounds such as Al₃Mg₂ and MgZn₂, which caused crack initiation exhibiting intergranular brittle fracture. Subsequently, under stress drive, it extends to SZ, mainly characterized by ductile fracture. Full article