Search Results (1,187)

Preclinical imaging has recently been expanded through the use of ostrich embryos as an alternative in vivo model. In ovo experiments represent a promising substitute for conventional rodent-based animal testing. For artifact-free dynamic nuclear medicine imaging, reliable immobilization of embryos is essential. Although previous studies have demonstrated the feasibility of isoflurane anesthesia, the kinetics and uptake mechanisms of isoflurane in ostrich embryos remain insufficiently characterized. The aim of this study was to characterize gas exchange dynamics in ostrich eggs and to quantify isoflurane uptake using two complementary approaches: indirect consumption measurements in a closed system and direct quantification by serial blood sampling. Fourteen ostrich eggs, including seven fertilized and seven unfertilized specimens, were analyzed at developmental stages up to day 37 of incubation. Gas exchange was assessed in a sealed container using a clinical anesthesia gas monitoring system to measure oxygen consumption and carbon dioxide excretion. Isoflurane uptake was evaluated during exposure to concentrations of 2%, 4%, or 6%. In a separate experimental series, serial blood samples were collected during and after exposure to the same concentrations to determine systemic uptake. Fertilized embryos showed progressive increases in metabolic activity, with a maximal oxygen consumption and carbon dioxide excretion of 116 mL/h/kg and 93 mL/h/kg on day 37. Indirect measurements demonstrated isoflurane uptake rates of up to 1.1 mL/min at 6%, with proportionally lower values at 4% and 2%. Blood analyses confirmed systemic absorption, peak concentrations of 160 µg/mL, and detectable residual levels for up to 120 min after exposure. These findings refine in ovo imaging. Full article

This study investigates the interplay between Portland cement strength class (32.5, 42.5, and 52.5) and fiber/cement ratio (ranging from 1/2 to 1/5 by weight) to optimize the physical-mechanical and thermal performance of cement-bonded fiberboards. The experimental data revealed a distinct trade-off: while reducing the fiber content towards a 1/5 ratio significantly improved flexural strength and dimensional stability through matrix densification, it inevitably compromised thermal insulation. Among the binders evaluated, the 42.5 strength class emerged as the most effective option, outperforming the 32.5 class and, notably, offering a more balanced profile than the 52.5 class. The highest stiffness was recorded with the 42.5 cement at a 1/5 ratio (modulus of elasticity (MOE): 5902 ± 532 N/mm²; modulus of rupture (MOR): 12.49 ± 0.6 N/mm²), yielding performance metrics comparable to the 1/4 ratio (MOR: 12.78 N/mm²). Furthermore, this formulation demonstrated superior moisture resistance, achieving water absorption (WA) values as low as 18.9%. Thermal conductivity (TC) measurements at 20 °C confirmed that while fiber-rich mixtures (1/2 ratio) favored insulation, the 42.5 cement at a 1/4 ratio maintained a competitive conductivity value (λ = 0.1625 W/mK), lower than that of the 52.5 grade, thereby striking a critical balance between structural integrity and thermal efficiency. Statistical analyses (Two-way ANOVA, p < 0.05) corroborated the significant influence of both cement type and mix ratio. Microstructural insights from Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM) suggest that the superior performance of the 42.5 cement is associated with optimized hydration kinetics and a well-graded particle size distribution (D50 = 14.80 µm), which together facilitated effective fiber encapsulation. Full article

Inorganic lead (Pb) poses a significant public health concern due to its toxicity and widespread industrial use. Dermal contact, an under-researched pathway of Pb exposure relative to inhalation and ingestion, is typically not factored into regulatory exposure limits because of the paucity of validated studies. This study investigated the influence of sweat on the bioaccessibility of inorganic lead for dermal absorption. Dissolution testing was conducted to determine the dissolution kinetics of inorganic Pb (lead nitrate) in synthetic sweat relative to deionized water (DIW). Particle sizes of samples ranged from 0.70 µm to 118 µm. Non-linear dissolution kinetics were observed in both DIW (control) and sweat. The iPb ion concentration in DIW after 3 h (test period) accounted for 100% of the initial mass of iPb, compared to 67% of the initial mass of iPb in sweat. Higher variability was observed in sweat (SD: 1.47 to 8.2) compared to DIW (SD: 0.80 to 3.88). Precipitation was observed in sweat but not in DIW. Wilcoxon rank-sum test indicated a statistically significant difference in dissolution between sweat and deionized water (Z = −4.50, p < 0.0001). Findings suggest that sweat composition limits the extent of dissolution of soluble inorganic Pb, thereby influencing its dermal bioaccessibility. Full article

This study presents an improved methodology for assessing the environmental sensitivity of the host rock in Huashan art paintings. A hygroscopic experiment was first designed to determine the moisture diffusion coefficient of the rock mass preserving the Huashan rock paintings, as verified by hygroscopic kinetics. Additionally, variations in color difference values were simultaneously used to quantitatively evaluate moisture absorption characteristics. Subsequently, a finite element (FE) simulation was conducted to assess potential damage to the rock art system with respect to varying environmental conditions. Regarding the correlated functions with consideration of the influencing factors, the environmental sensitivity of the host rock in Huashan art paintings was clarified to illustrate the deterioration process resulting from the combined effects of temperature and humidity. It is found that the deformation gradient (F) and maximum tensile stress (σ_max) exhibit a linear relationship with ambient temperature (T_a), and an exponential relationship with heat transfer coefficient (h). The ambient humidity (H_en) and surface humidity exchange coefficient (f) primarily influence the water content of the rock mass. This insight into the host rock in Huashan art paintings provides a valuable approach to highlight the active role of environmental conditions and offers an additional methodology to understand the detachment of large superficial rock flakes and the granular disintegration of the rock. Full article

Contamination of water bodies caused by increasing human and industrial activities poses a serious threat to human health and environmental sustainability, highlighting the need for green and efficient remediation strategies. In this study, a facile hydrothermal synthesis followed by controlled calcination was developed to fabricate phase-pure α- and β-Bi₂O₃ with a unique coral-like hierarchical morphology as visible-light-active photocatalysts. Phase selectivity was achieved by tuning the calcination temperature, yielding pure β-Bi₂O₃ while preserving the hierarchical structure. Optical characterization revealed a narrower bandgap for β-Bi₂O₃ (2.24 eV) compared to α-Bi₂O₃ (2.75 eV), favoring visible-light absorption. Photocatalytic performance was evaluated using Rhodamine B as a model pollutant, where β-Bi₂O₃ achieved complete degradation within 240 min, significantly outperforming α-Bi₂O₃. The degradation followed pseudo-first-order kinetics, and the catalyst exhibited excellent robustness and reusability. To further demonstrate applicability toward persistent contaminants, Methyl Orange (MO) and the antibiotic ciprofloxacin (CIP) were employed as additional model pollutants. The coral-like β-Bi₂O₃ showed high visible-light activity toward MO, including complete removal under acidic conditions. Moreover, efficient degradation of CIP was achieved at neutral pH, with 90% removal within 150 min and complete degradation after 240 min. Overall, these results highlight coral-like β-Bi₂O₃ as an efficient standalone photocatalyst for visible-light-driven degradation of dye and pharmaceutical pollutants. Full article

Spent carbon cathode (SCC), a hazardous solid waste discharged from aluminum electrolysis, exhibits significant fluoride and cyanide leaching toxicities. Existing high-temperature disposal strategies are constrained by high investment costs for specialized equipment, low product added value, and unclear application scenarios, hindering their large-scale implementation. Consequently, substantial quantities of SCC remain underutilized, resulting in the waste of valuable carbon and fluoride components. This study focuses on the targeted conversion of valuable components in SCC through the innovative integration of simple processes, including atmospheric high-temperature roasting, deep purification, Al-based inducer addition, and pH regulation. Volatilization kinetics and solution equilibrium chemistry were used to investigate impurity removal mechanisms and to guide cryolite synthesis, respectively. The results demonstrate the successful recovery of high-purity regenerated graphite with a high carbon content, low sulfur content, and a high degree of graphitization. Simultaneously, cryolite with a high NaF/AlF₃ molecular ratio was synthesized from the roasting flue gas absorption liquor by controlling ionic composition and pH. Guided by the principles of cleaner production and resource recycling, the entire recovery process generates negligible waste gas, wastewater, or solid residue emissions. In conclusion, the proposed disposal strategy achieved the targeted conversion of SCC into high-value products while mitigating environmental pollution risks, offering both environmental and economic benefits. This innovative design provides a feasible pathway for the large-scale disposal and utilization of SCC. Full article

The primary shelf life (PSL) of fresh vegan spinach gnocchi packaged under a modified atmosphere (MAP) was investigated. Microbiological, physicochemical, and sensory properties were monitored during storage at three temperatures (4, 8, and 12 °C). The microbial load remained below the limit considered safe (3 log CFU g⁻¹) in all samples during storage at all tested temperatures. Storage time significantly increased the hardness of uncooked gnocchi (p < 0.05) and the water absorption index (p < 0.05). Moreover, at higher storage temperatures, the kinetic rate of hardness decreased in uncooked gnocchi (0.29 N day⁻¹ at 12 °C vs. 0.35 N day⁻¹ at 4 °C). Conversely, in cooked gnocchi, as the storage temperature increased, the rate of hardness acceleration increased. The sensory analysis results varied according to storage temperature, and the Overall Quality Index (OQI), combined with principal component analysis (PCA), was used to determine PSL values. The Arrhenius relationship successfully described the temperature dependence of reaction rate constants, and the calculated Q₁₀ value (3.0) confirmed hardness as the quality attribute most affected by temperature. OQI showed a strong correlation with cooked-gnocchi hardness, and a sensory cutoff of 6.5 was established and confirmed by the sensory panel. The corresponding hardness rejection value was 12.1 N. The PSL was estimated based on sensory and texture criteria, as microbial quality was not a limiting factor. Under non-isothermal cold-chain conditions, PSL was predicted using the time–temperature tolerance (TTT) approach, yielding a value of 42 ± 3 days. Full article

Oxygenic and anoxygenic photosynthesis are initiated through the absorption of light by chlorophyll and bacteriochlorophyll photosynthetic pigments, respectively, which function as light-harvesting (antenna) and redox pigments on the photosynthetic membrane that trap and convert the absorbed optical energy into chemical energy. While several studies have characterized the ultrafast spectra, kinetics, and structures of the light-harvesting and reaction center complexes that contain the photosynthetic pigments, a detailed understanding of how the ultrafast excited-state dynamics vary across different photosynthetic pigments is lacking. Such information is critical in understanding the molecular mechanisms of both artificial and natural photosynthetic systems. In this study, we conducted ultrafast time-resolved absorption spectroscopy on chlorophyll and bacteriochlorophyll photosynthetic pigments at room temperature to directly compare the spectra and kinetics of their transient, excited electronic states formed following photon absorption. The recorded ultrafast spectral and kinetic data, spanning the femtosecond to sub-microsecond timescales, show interesting similarities and differences between these two distinct types of photosynthetic pigments. These experimental results help clarify the relationship between photosynthetic pigment structure and the resultant ultrafast processes in the oxygenic and anoxygenic photosynthetic reaction mechanisms. Full article

Composite superabsorbents (C-SAPs) that combine synthetic and polysaccharide components hold great promise for sustainable agriculture. They improve water management and enable the controlled release of agrochemicals. However, increasing the polysaccharide content to enhance biodegradability often reduces water absorption capacity. In this study, we explore plasticization with succinic acid esters as a strategy to overcome this limitation. Our goal is to establish structure–property relationships between plasticizer architecture and C-SAP performance. A series of carboxymethyl cellulose-based superabsorbents was synthesized via radical copolymerization. They were then plasticized with 5 wt.% of dibutyl succinate, di-sec-butyl succinate, or di-iso-butyl succinate. The resulting materials were characterized using FTIR spectroscopy, differential scanning calorimetry, rheological tests, swelling kinetics, and phytotoxicity assays against oilseed radish and common oat. Increased plasticizer branching and molecular volume enhanced polymer network elasticity, lowered the glass transition temperature (by up to 6 °C), and increased the equilibrium swelling ratio by up to 64% compared to the unplasticized C-SAP (661 ± 17 vs. 402 ± 10 g/g). All plasticized C-SAPs retained more than 80% of their initial swelling capacity over five swelling–deswelling cycles across pH 3.0–9.2. They also showed no phytotoxicity at agriculturally relevant concentrations. These findings demonstrate that molecular engineering of plasticizer architecture enables simultaneous optimization of water absorption and environmental safety in C-SAPs for agricultural use. Full article

Cancer is increasingly recognized as a systems-level disorder characterized not only by genetic alterations but also by persistent dysregulation of stress-adaptive signaling networks integrating inflammation, metabolism, immune modulation, and cellular plasticity. Within this framework, reactive oxygen species (ROS) function as flux-dependent regulators of signaling fidelity rather than merely cytotoxic byproducts. Therapeutic strategies centered on single high-affinity targets or indiscriminate antioxidant suppression often fail to achieve durable responses in redox-heterogeneous and inflammation-driven malignancies. Multi-component herbal formulations represent chemically diverse systems capable of distributed pharmacodynamic modulation across interconnected signaling nodes and heterogeneous pharmacokinetic exposure profiles arising from multi-constituent absorption kinetics. Ojeoksan (Wu Ji San), a classical East Asian multi-herbal decoction, has accumulated experimental and clinical evidence demonstrating regulatory effects on inflammatory mediators, metabolic homeostasis, mitochondrial stress responses, and immune signaling pathways. Rather than inducing abrupt pathway inhibition, OJS appears to exert graded, parallel modulation across multiple redox-sensitive axes. Here, we reinterpret OJS within a flux-based pharmacological framework, conceptualizing it as a distributed redox-buffering architecture rather than a direct cytotoxic agent. By integrating Korean and Chinese research traditions with systems-level redox modeling and electrochemical perspectives, we propose that multi-component formulations may enhance pharmacodynamic robustness through controlled modulation of ROS amplitude and multi-node buffering while temporally distributing pharmacodynamic signals through multi-component pharmacokinetic synchronization. From a formulation science standpoint, such distributed electrochemical diversity may expand therapeutic tolerance windows and mitigate compensatory pathway escape in chronic inflammatory and therapy-resistant cancers. This perspective supports repositioning multi-herbal formulations as network-aligned pharmacological systems compatible with modern molecular pharmacology formulation-level design principles and rational combination therapy strategies. Full article

Background: Pantoprazole is a widely used proton pump inhibitor that is highly unstable under acidic conditions. This limits the performance of conventional formulations and typically requires enteric-coated dosage forms or alternative modified-release approaches. This study reports the development of polymeric matrix mini-tablets designed to protect pantoprazole during gastric exposure and to enable pH-dependent release under intestinal conditions. The formulations combine Eudragit^® S 100, a pH-dependent polymer, with HPMC, a hydrophilic matrix former that modulates drug release through hydration and swelling. Methods: Matrix mini-tablets were prepared by blending pantoprazole with selected excipients at optimised proportions and compressing the blends by direct compression using an eccentric tablet press. Powder blends and mini-tablets were characterised according to pharmacopoeial specifications. Analytical techniques—including High-Performance Liquid Chromatography (HPLC), Differential Scanning Calorimetry (DSC), Fourier-Transform Infrared Absorption Spectroscopy (FT-IR), Powder X-Ray Diffraction (PXRD), and Scanning Electron Microscopy (SEM)—were employed to evaluate drug content uniformity, thermal behaviour, and potential drug–excipient interactions. In vitro dissolution studies were performed under sequential pH conditions, and the release kinetics were analysed using mathematical models. Results: Dissolution testing identified formulations F2 and F6 as providing the most suitable gastro-resistant performance in the acidic stage, together with sustained release up to 24 h. Kinetic modelling supported formulation-dependent release mechanisms, and multivariate analysis (PCA) highlighted relationships between physico-mechanical attributes and drug-release behaviour. Conclusions: The proposed matrix system shows potential as a robust, coating-free platform for the modified delivery of acid-labile drugs using direct compression, simplifying manufacturing. These findings support the rational design of oral modified-release formulations based on polymeric matrices. Full article

Amyloidosis is characterized by the deposition of misfolded proteins as highly stable, insoluble β-sheet-rich fibrils, posing a major therapeutic challenge due to their resistance to degradation. Insulin-derived amyloidosis at subcutaneous injection sites is a clinically significant complication in patients with diabetes, leading to impaired insulin absorption, unpredictable glycemic control, substantially increased insulin dose requirements, and localized masses (amyloidomas) that may require surgical excision when symptomatic. In this study, we evaluated sodium oleate-functionalized magnetic nanoparticles (MNs) with a hydrodynamic diameter of 50 nm with a magnetite (iron oxide—Fe₃O₄) core as a targeted physical intervention to disrupt preformed insulin amyloid fibrils. The strategy exploits localized nanoscale hyperthermia generated by MNs under a high-frequency radiofrequency (RF) field (1.65 MHz). Fibril integrity and disassembly kinetics were assessed using Thioflavin T (ThT) fluorescence assays and fluorescence microscopy. RF-activated MNs induced rapid, concentration-dependent fibril disruption; notably, at 2 mg/mL MNs, near-complete disassembly was achieved within 15 min—a timeframe compatible with clinical procedures. Neither RF nor MNs alone produced significant effects, confirming a synergistic magnetothermal mechanism. These results provide a proof of concept for a minimally invasive, externally triggered approach to clear localized insulin amyloid deposits, offering promising potential as a novel therapeutic strategy for managing injection-site amyloidosis in diabetic patients, where current options remain limited and often inadequate. Full article

As a primary reaction medium, water profoundly influences the kinetics and mechanisms of chemical processes. External physical treatments, such as vibration, can alter the physicochemical properties of water, thereby modifying reaction outcomes. This study aimed to investigate the effect of vibrational iterations (I0–I7) prepared using the “crossing” technology on the kinetics of the oxidation–reduction reaction between methylene blue and ascorbic acid, a standard model for evaluating external influences. Initial characterization revealed that while pH remained stable across all samples, electrical conductivity and dissolved oxygen levels deviated significantly from the control (intact water), with oxygen concentrations measuring either higher or lower than the control. Following the dissolution of methylene blue in these iterations, absorption spectroscopy was used to monitor decolorization kinetics. Different vibrational iterations influenced distinct kinetic parameters, including the rate constant, half-reaction time, and average reaction rate. Depending on the number of processing steps used to prepare the iterations, these parameters exhibited deviations ranging from 3% to 9% compared to the control. This suggests a complex relationship between the aqueous medium’s structural–dynamic properties and the reactants’ supramolecular organization. These findings underscore the potential of vibrational iterations as a tool for modulating chemical reaction kinetics through aqueous medium engineering. Further research is needed to elucidate the underlying mechanisms and expand the applicability of this approach to other systems. Full article

To improve the impact resistance of composite materials, this study adopted the structures in the impact region of mantis shrimp appendages as a bionic prototype, designing a composite structure with a rigid outer layer and flexible sinusoidal inner layer. Meanwhile, bionic arrangement was conducted on the fibers in three directions (X-Y, X-Z, and Y-Z planes) within the flexible layer to regulate the crack propagation path during the impact process. Finite Element Method and low-velocity impact tests were carried out to verify the structural effectiveness, analyze the energy absorption mechanism, and investigate the failure modes. Relative to the basic rigid-flexible structure, the brick-and-mortar (Y-Z) and vertical-horizontal alternating fiber (X-Y) models show a 94% and 109% improvement in kinetic energy absorption efficiency, respectively. Additionally, the catastrophic damage in the impact center area caused by crack concentration is significantly reduced. This study confirms that the bionic 3D arrangement of fibers can realize interlayer connection, optimize crack distribution, and enhance energy dissipation, thereby improving the impact resistance of composite materials. Full article

Hierarchical In₂MnS₄ microflowers were synthesized via a hydrothermal approach and evaluated as multifunctional photo-/electrocatalysts for crystal violet (CV) dye degradation and methanol oxidation. The synthesis strategy produced three-dimensional flower-like architectures composed of nanoscale subunits with high crystallinity and uniform elemental distribution. Optical characterization revealed strong visible-light absorption with a bandgap of approximately 1.74 eV, indicating suitability for solar-driven photocatalysis. In₂MnS₄ microflowers achieved 96.6% degradation of CV dye within 100 min, whereas negligible activity was observed without the catalyst. Kinetic analysis followed a pseudo-first-order model with an apparent rate constant of 0.029 min⁻¹. The catalyst maintained stable performance over four consecutive cycles, confirming good recyclability. Photoelectrochemical measurements showed a stable photocurrent response and reduced charge-transfer resistance, indicating efficient separation and transport of photogenerated charge carriers. Furthermore, electrochemical measurements revealed increased anodic responses and sustained current behavior in the presence of methanol, suggesting an electrochemical response upon methanol addition. These results highlight In₂MnS₄ microflowers as promising visible-light-responsive materials for environmental remediation and energy-related catalytic applications. Full article