Chemistry and Materials Science

Abstract: Cortisol, as a crucial biomarker reflecting psychological stress and physiological status, requires rapid and sensitive detection for health assessment and disease diagnosis. Conventional methods are time-consuming, operationally complex, and costly, limiting their use for point-of-care testing. This study reports a flexible, aptamer-based capacitive biosensor that exploits alternating current electrokinetics for ultrafast detection of cortisol in small-volume samples. Aptamers are immobilized via Au-S self-assembly on gold interdigitated electrodes on a PET substrate, and ACEK-induced fluid motion and dielectrophoresis rapidly enrich cortisol at the electrode interface, producing measurable interfacial capacitance changes ΔC/C₀. Experimental results demonstrate detection limits of 0.412 ng/mL in PBS and 0.337 ng/mL in artificial sweat, with response times within 1 minute and excellent linear response across 1-1000 ng/mL concentrations. Requiring only 10 μL of sample, the sensor exhibits good repeatability, specificity, and interference resistance, making it suitable for rapid cortisol level detection. To enhance detection stability, this study designed and integrated a microfluidic chip, enabling efficient sample delivery and stable detection. The system demonstrates strong interference resistance, revealing potential applications in health management and disease monitoring.

Abstract: The irreversible cyclic strain/stress in battery electrodes during ion intercalation/deintercalation drives mechanical energy dissipation, accelerating cycle life degradation. However, the lack of quantitative methods to assess stress and mechanical energy dissipation hinders a mechanistic understanding of mechanical behavior in electrochemical systems. This work aims to develop a theoretical framework to quantify stress and strain energy evolution in practical heterogeneous composite electrodes. Under assumptions of plane stress and elastic deformation, the average stress/strain energy per cycle can be derived for battery electrode during dynamic ion insertion/extraction. By considering a concentration-dependent modulus, the present framework allows for the simultaneous determination of both the bilayer stress, the apparent and local modulus of the electrode through measurements of its curvature and intrinsic chemical strain.

Abstract: [¹¹C]Choline ([¹¹C]CHO) has reemerged as a radiopharmaceutical tracer for positron emission tomography (PET) diagnostics and optimized synthesis setups are thus needed to meet the increased demand, often on existing production lines. Originally, [¹¹C]CHO has experienced a decline in use for PET diagnostics, particularly in prostate cancer imaging due to radiopharmaceuticals with higher target specificity. However, recent studies have demonstrated superior sensitivity and diagnostic accuracy of [¹¹C]CHO for localizing autonomous adenomas in primary hyperparathyroidism (PHPT) compared to conventional ⁹⁹ᵐTc-sestamibi scintigraphy. The PET-scan is used prior to surgery, but not for the diagnosis of PHPT. The patient compliance is high due to the relatively short time in the scanner. With this renewed clinical relevance, optimization of [¹¹C]CHO synthesis is warranted, as standard production protocols typically yield only 2.5–3.0 GBq. In this study, three critical steps in the synthesis process on a TracerMaker module were systematically evaluated and optimized. (1) Extending the irradiation time from 25 to 42 minutes produced no significant increase in radiochemical yield (RCY). (2) Increasing the precursor, dimethylaminoethanol (DMAE) loading volume to 150 µL divided across two serially connected Sep-Pak Accell CM Plus Light cartridges resulted in a twofold RCY increase but also elevated residual DMAE levels in the final product. (3) Increasing washing volumes of ethanol and water did not improve purification efficiency; however, replacing the two stacked cartridges (2 × 130 mg) with a single cartridge containing a higher sorbent mass (360 mg) achieved effective DMAE removal while maintaining high RCY. These findings demonstrate a practical route for optimizing [¹¹C]CHO synthesis to meet the growing clinical demand of [¹¹C]CHO for imaging of PHPT.

Abstract: Increasingly stringent fire safety, environmental, and occupational health regulations have accelerated the development of sustainable fire-resistant materials. WEICs have gained attention as multifunctional passive fire protection systems due to their strong substrate adhesion, low volatile organic compound emissions, and environmentally compatible formulations. This review highlights recent advances in epoxy-based intumescent composite coatings, focusing on how formulation design and microstructural characteristics influence fire-protective performance. Key flame-retardant mechanisms, including thermal degradation, chemical transformation, and char expansion behaviour, are discussed within heterogeneous composite systems. Emphasis is placed on the synergistic interactions among acid sources, carbon-forming agents, and blowing agents, as well as on incorporating fillers and reinforcing phases to enhance thermal insulation and expansion stability. Emerging strategies involving nanostructured reinforcements, bio-based additives, and hybrid composites are also evaluated for their potential to enhance char strength, mechanical durability, and heat resistance. Despite notable progress, challenges remain in long-term durability, interfacial compatibility, economic feasibility, and large-scale implementation, highlighting the need for halogen-free, low-toxicity intumescent coating technologies.

Abstract: This review intends to provide an insight into the wide range of possibilities for vegetable oils to be used as solvents to extract natural ingredients for various applications with special emphasis on antioxidants. The potential of using oils as food-grade solvents for extraction of carotenoids, crocins, curcuminoids, cannabinoids, capsaicinoids, different volatile organic compounds and other lipid-soluble phytochemicals from plant sources and by-products is summarized. Most studies focus on optimizing extraction parameters and evaluating the physical and chemical characteristics of the obtained oily plant extract. On the one hand, these infused or enriched oils can be considered as plant extracts, but, on the other hand, one should not ignore the fact that lipid oxidation is a problem that needs to be addressed. The characterization and analysis of the obtained oily extracts is closely related to their specific application in the food or cosmetic industry. Despite all the advantages, disadvantages related to the stability of the fortified oils are discussed as well.

Abstract: This study looked at the distribution of major and minor volatile components in distillates created by combining two plum types, Stanley and Požegača. Two methods of blending were used: (i) during fermentation and (ii) by macerating fresh Požegača in raw Stanley distillate and then redistilling the mixture. Plums were combined in three different ratios: 90:10, 70:30, and 50:50. The blending was done to enhance the plum aroma of the drinks. Major volatile components were measured by GCxFID analysis, while minor components were measured using GCxGCxMS. All produced distillates had the usual values of the main volatile components. Compared to the blending procedure, the distribution of minor volatile components in the samples varied more according to the plum variety and its ratio in the blend. Nevertheless, samples made by fermentation mixing had higher concentrations of α-terpineol, heptanal, benzaldehyde, and γ-dodecalactone. Fresh plum maceration yielded significantly higher concentrations of benzyl alcohol, 2-phenylethanol, octanoic acid, and (E)-β-damascenone. The sensory perception of spirits is significantly influenced by terpenes. Stanley spirits are distinguished for myrcene, which gives them a pleasing mouthfeel. Geraniol α-terpeneol and γ-dodecalactone, which are more typical for Požegača spirit, have a positive impact on the plum like odour of spirits. Isopentyl acetate, ethyl octanoate, 2-phenylethyl acetate, ethyl dodecanoate, heptanol, and octanoic acid were other positive aromatic compounds. Blending different plum varieties is a successful way to improve the flavour profile of spirits.

Abstract: The continuous emergence of SARS-CoV-2 variants necessitates the identification of effective multi-target antiviral agents with enhanced stability and binding efficiency. This study employed an integrated computational approach, including molecular docking, molecular dynamics (MD) simulations, free energy landscape (FEL) analysis, and Molecular Mechanics Poisson-Boltzmann Surface Area (MM-PBSA) calculations, to evaluate the inhibitory potential of twenty natural compounds against SARS-CoV-2 proteins 7XJW, 8DRW, and 9PFH. Molecular docking identified Amentoflavone as the most promising candidate, exhibiting strong binding affinities toward all targets through favorable hydrogen-bond and hydrophobic interactions within the active sites. Interaction analysis revealed that its biflavonoid scaffold promoted extensive ligand–protein complementarity through hydroxyl and aromatic functional groups. MD simulations demonstrated stable protein-ligand complexes, characterized by low fluctuations in RMSD, RMSF, SASA, and radius of gyration values throughout the 100 ns trajectories. Persistent hydrogen-bond interactions further supported complex stability. FEL analysis revealed compact low-energy conformational basins, indicating thermodynamically favorable binding states. MM-PBSA calculations confirmed favorable binding free energies primarily driven by van der Waals and electrostatic contributions, with the 7XJW-Amentoflavone complex exhibiting the most favorable energetic profile. Overall, these findings highlight Amentoflavone as a promising multi-target inhibitor and potential lead compound for future antiviral drug development and experimental validation against SARS-CoV-2.

Abstract: Industrial synthetic dyes represent a major source of water pollution because current treatment methods fail to remove them efficiently prior to discharge. Consequently, developing cost-effective and highly efficient technologies for wastewater systems is essential. Adsorption satisfies these demands and easily couples with other industrial effluent treatments. This study focuses on nanoporous anodic aluminum oxide (AAO), an outstanding adsorbent known for its versatility, high specific surface area, significant porosity, and thermal stability. Although the adsorption capacity of this nanoadsorbent has been recently studied, this work specifically evaluates the performance of AAO modified through different thermal and chemical treatments for the removal of Eriochrome Black T from aqueous solutions. Within a 1-h process, the applied treatments significantly enhanced AAO adsorption performance: standalone calcination and chemical etching led to a 10% increase in dye removal efficiency, while combining calcination with alkaline etching resulted in a 38% improvement. Furthermore, the combined treatment was demonstrated to enhance the adsorption process at alkaline pH levels (up to pH 10), and the modified AAO could be reused up to four times while maintaining a significantly high removal efficiency. Finally, this study provides key insights into the underlying phenomena governing the adsorption of anionic dyes onto AAO nanostructures.

Abstract: The transition toward a sustainable hydrogen economy demands cost-effective, durable, and highly active catalysts that span the entire H2 value chain from green production through storage and transport to end-use conversion. Carbon-based catalytic materials have emerged as a uniquely versatile platform, offering tunable electronic structure, abundant defect- and edge-derived active sites, hierarchical porosity, chemical robustness, and compatibility with both metal-free and single-atom architectures. This review provides a comprehensive overview of advanced carbon-based catalysts designed for the hydrogen economy. We begin with the fundamentals of heteroatom doping, defect and curvature engineering, and M–N4/M–N3 coordination environments that govern binding of hydrogen-relevant intermediates (ΔG_H*, ΔG_OH*, ΔG_O*). Three application pillars are then systematically examined: (i) hydrogen production through HER and OER across PEMWE, AEMWE, AWE, and SOEC platforms, including emerging seawater and biomass-/waste-coupled electrolysis; (ii) hydrogen storage and chemical carriers, encompassing physisorption on porous carbons and catalytic (de)hydrogenation of liquid organic hydrogen carriers, ammonia, and formic acid; and (iii) hydrogen utilization in PEMFCs, AEMFCs, direct liquid fuel cells, and hydrogen-coupled CO₂ and N₂ reduction. Particular emphasis is placed on structure–activity descriptors, operando mechanistic probes, device-level benchmarking from rotating-disk electrodes to membrane-electrode assemblies, and techno-economic considerations including the levelized cost of hydrogen. We conclude by highlighting critical challenges — carbon corrosion, PGM-free durability, and scalable synthesis — and outline future directions that integrate AI-accelerated discovery, atomic-precision synthesis, and biomass-derived circular-economy carbons for next-generation hydrogen technologies.

Abstract: Octopus maya is a fast-growing species from the Yucatán Peninsula with high economic relevance, accounting for a major share of regional fishery production. However, a sig-nificant fraction of the organism, rich in type I collagen, is discarded as by-products, representing a promising and underutilized source for sustainable biomaterials. This study evaluated, through a 3² factorial design, the effect of two factors: (1) the type of food-grade polysaccharide, chitosan (Ch), hydroxypropyl methylcellulose (H), or starch (S), and (2) its proportion in blendings with Octopus maya insoluble collagen (CIPM), obtained by ultrasound-assisted extraction, using polysaccharide:collagen ratios of 30:70, 50:50, and 70:30 (w/w), and using rheological and dynamic mechanical properties of film-forming solutions (FFS) as response variables. This approach aims to valorize oc-topus by-products through the recovery and functional utilization of collagen. Rheo-logical properties were determined by rotational and oscillatory rheometry at 25 °C, with flow curves fitted to the Carreau-Yasuda model. All formulations exhibited pseu-doplastic behavior (n < 1), with viscosity decreasing as shear rate increased. Pure CIPM showed high viscosity (190.36 Pa·s at 1 s⁻¹), which decreased (0.3-10.44 Pa·s) in HPMC and chitosan systems, favoring applications requiring fluidity, such as spray coatings or film-forming solutions. In contrast, starch-based systems exhibited higher viscosities (33.54-197.53 Pa·s) and a more structured viscoelastic profile (G′ > G″), forming networks suitable for thick coatings or gels requiring structural stability. These results demonstrate that CIPM-polysaccharide systems enable tunable rheological properties, supporting the use of Octopus maya collagen as a sustainable functional material for advanced food and biomaterial design.

Abstract: Research on the effect of ammonium chloride (NH₄Cl) electrolyte on graphene nanosheet (GNS) electrodes derived from candlenut shells (Aleurites moluccana (L.) Willd) as primary battery cathodes has been conducted. GNS was synthesized via pyrolysis and modified with NH₄Cl to produce G–N 0.5 M, G–N 1.0 M, G–N 2.0 M, and G–N 3.0 M samples. The materials were characterized using XRD, SEM-EDX, and electrical measurements at 0.5–1.5 V. XRD results show peaks at 2θ ≈ 25° and 44.27° corresponding to C(002) and C(100) planes, while G–N samples exhibit new diffraction peaks at (111), (200), (220), (311), (222), and (400), indicating NH₄Cl incorporation. SEM analysis reveals a transition from layered GNS morphology to more wrinkled and agglomerated structures with increasing NH₄Cl concentration, supported by EDX showing decreasing carbon content and the presence of chlorine (up to ~5.9%). Electrical conductivity increases significantly from commercial battery to GNS and further to G–N samples, reaching ~1.30 S·cm⁻¹ for G–N 2.0 M, along with energy density (~605 Wh·kg⁻¹) and power density (~605 W·kg⁻¹). These results indicate that NH₄Cl modification enhances electrochemical performance and highlights the importance of electrolyte variation in optimizing GNS-based electrodes for primary battery applications.

Abstract: Long-term clinical translation of left ventricular assist devices (LVADs) is severely hampered by thromboembolism and device-related infection, both originating from inadequate biocompatibility of the device-blood interface. Current titanium surface modifications fail to simultaneously deliver durable antithrombotic and antibacterial performance, while conventional polydopamine-copper (PDA-Cu) coatings suffer from inherent limitations. Herein, we report a one-step rapid co-polymerization strategy based on mussel-inspired polyphenol chemistry to fabricate a copper-integrated polydopamine/tannic acid nanocoating on titanium (Ti/PDT(Cu)). By incorporating tannic acid rich in catechol/pyrogallol moieties, we achieve synergistic acceleration of dopamine oxidative polymerization with copper ions, dramatically shortening the fabrication time to 8 h (vs. >24 h for traditional PDA coatings). This process simultaneously constructs a robust dual-crosslinked network through covalent/hydrogen bonds and metal-phenolic coordination, exhibiting a uniform nanoscale-roughened structure. Comprehensive physicochemical characterizations confirm homogeneous coating deposition, excellent hydrophilicity, uniform Cu distribution, and superior long-term structural stability (95.68% thickness retention after 7 days of physiological immersion). The optimized coating displays broad-spectrum and durable antibacterial activity, with 92.79% and 89.73% reduction of E. coli and S. aureus at 24 h, respectively, and retains >89% antibacterial efficacy after 7 days of continuous elution. Moreover, the coating enables stable and sustained catalytic nitric oxide generation (43.85 ± 2.36 μM cumulative release over 14 days) that mimics endothelial function, resulting in 69.4% inhibition of platelet adhesion and an ultralow hemolysis ratio of 0.97%. Critically, it maintains excellent cytocompatibility with L929 fibroblasts (>90% cell viability after 72 h co-culture). This work overcomes the key bottlenecks of conventional PDA-based functional coatings, realizes synergistic antithrombotic and antibacterial dual functions tailored for LVAD implantation, and provides a facile and robust surface engineering platform for long-term implantable cardiovascular devices.

Abstract: 6061 aluminum alloy is lightweight and has good thermal conductivity, while 304 stainless steel possesses excellent mechanical properties and corrosion resistance; both have broad application prospects in cooling circuits. Propylene glycol coolant shows great potential in liquid cooling systems due to its low toxicity and good antifreeze properties. However, during operation, galvanic corrosion may occur when the two metals come into direct contact within the coolant, thereby threatening system safety and service life. This study focuses on 6061 aluminum alloy, 304 stainless steel, and their galvanic couples. Using electrochemical testing, SEM, 3D confocal microscopy, and XPS to systematically investigate their self-corrosion and galvanic corrosion behavior in propylene glycol coolant at pH values of 4.8, 6.8, and 8.8. The results indicate that 6061 aluminum alloy is more sensitive to pH changes; its corrosion resistance first increases and then decreases as pH rises, with the least corrosion occurring at pH = 6.8 and the most severe at pH = 4.8. 304 stainless steel exhibited lower corrosion rates at pH 6.8 and 8.8, but corrosion significantly worsened at pH 4.8. For the 6061 aluminum alloy/304 stainless steel couple, the galvanic current first decreased and then increased with rising pH, while the galvanic potential first increased and then decreased. The 6061 aluminum alloy consistently acted as the anode, and the 304 stainless steel consistently acted as the cathode, with the highest sensitivity to galvanic corrosion observed at pH 4.8. XPS analysis shows that under different pH conditions, the corrosion products of 6061 aluminum alloy are Al(OH)3 and Al2O3, while the main components of the passivation film on 304 stainless steel remain unchanged.

Abstract: This study investigated subcritical water extraction (SWE) as an alternative to hydroalcoholic extraction for the production of Echinacea purpurea root extracts standardized to hydroxycinnamic acids (cichoric and caftaric acids). Extractions were performed at 100°C, 125°C, 150°C, and 170°C for 10 min–30 min. The recovery of hydroxycinnamic acids was strongly influenced by extraction temperature, with the highest values obtained within the range of 100°C–125°C. Further optimization identified 110°C for 10min as the optimal condition, yielding the highest cumulative recovery of hydroxycinnamic acids (1.87±0.10% of dry material). In the resulting dry extracts, SWE at 100°C–125°C produced hydroxycinnamic acid contents of 5.5%–7.1%, whereas the total dry extract yield increased from 24%–28% at 100°C to 40%–41% at 150°C–170°C. Higher temperatures, however, reduced hydroxycinnamic acid content to 0.6%–1.7%, indicating degradation of the target compounds. In contrast, total polyphenol recovery increased continuously with temperature, reaching 4.86% at 170°C for 30 min. This was accompanied by marked increases in free caffeic acid and gallic acid, reaching 458.5 mg/100g DW and 945.7 mg/100g DW, respectively, suggesting the release of bound phenolics following partial disruption of plant cell wall structures. SWE also enhanced the extraction of carbohydrates, uronic acids, fructans, proteins and organic acids, demonstrating extensive temperature-dependent modification of the root matrix. 5-HMF was not detected in extracts obtained below 125°C, but increased progressively at higher temperatures, reaching 200 mg/100 g at 170°C. Biological evaluation in HT29 cells showed favorable cytocompatibility of SWE extracts, confirmed by cell viability, morphological assessment and low DNA damage in the Comet assay. Overall, SWE enables the production of hydroxycinnamic acid-standardized E. purpurea extracts without organic solvents, supporting its application in pharmaceutical, nutraceutical, food and cosmeceutical products.

Abstract:

Background/Objectives: Alzheimer’s disease (AD) is a neurodegenerative disorder with a complex pathomechanism. Acetylcholinesterase (AChE) and monoamine oxidase-B (MAO-B) are key targets regulating neurotransmitter levels, and dual inhibitors (compounds 1–46) were designed as experimental candidates for AD therapy. Methods: Drug-likeness parameters were estimated using pkCSM, SwissADME web tools, and MoloVol software (v1.2.0). SwissADME predicted gastrointestinal absorption and blood–brain barrier penetration, whereas pkCSM evaluated P-glycoprotein recognition and CYP450 inhibition. Toxicological profiles of compounds (1–46) were assessed with DataWarrior software (v06.05.04), which classified them as mutagenic, carcinogenic, reproductive, or irritant. Results: Most compounds complied with Lipinski’s rule (excluding 12 and 35) indicating favorable absorption and permeability. All compounds showed TPSA < 140 Å2, indicating good intestinal absorption, while compounds 1, 3–6, 8, 11-16, 18, 19, 27, 30, 31, 34, 36-38, and 44–46 displayed TPSA < 60 Å2, suggesting blood–brain barrier penetration. The majority of compounds were predicted P-glycoprotein substrates, potentially limiting oral absorption and blood-brain barrier penetration. Metabolic profiling revealed inhibition of CYP1A2, 2C19, 2C9, 2D6, and 3A4, highlighting drug–drug interaction risks. Toxicological analysis identified mutagenicity (compounds 4, 5, 19, 20 and 27), carcinogenicity (compounds 4, 5, 8, 18 and 19), reproductive toxicity (compounds 15, 16 and 19–23), and irritant effects (compounds 7, 11, 17 and 20). Conclusions: Computational findings support further in vitro and in vivo evaluation of compounds 1, 3, 6, 13, 14, 30, 31, 34, 36–38, and 44–46 as dual AChE/MAO-B inhibitors and potentially new drugs for AD treatment.

Abstract: Anthracycline agents, principally doxorubicin and daunorubicin, are widely used in oncology yet carry a narrow therapeutic index and pronounced interindividual pharmacokinetic variability that exposes patients simultaneously to the risk of subtherapeutic dosing and cumulative cardiotoxicity. Conventional therapeutic drug monitoring (TDM) based on periodic venous sampling and offline high-performance liquid chromatography cannot resolve the sub-minute concentration dynamics that determine organ-specific drug exposure. Electrochemical aptamer-based (EAB) sensors couple nucleic-acid aptamers, self-assembled monolayers, and methylene blue redox reporters on gold microelectrodes to convert binding-induced conformational changes into real-time, reagent-free electrochemical signals. Recent advances in this field fall into five areas: signal interrogation strategies, from kinetic differential measurement to calibration-free Fourier-transform impedance spectroscopy (FFT-EIS); interface engineering including nanostructured electrodes and AI-guided aptamer design; in vivo multi-compartment pharmacokinetic monitoring and closed-loop feedback drug delivery; the mechanisms of in vivo signal drift alongside antifouling countermeasures spanning hydrogel barriers, zwitterionic brushes, and xenonucleic acid backbone substitution; and FDA premarket pathways and clinical translation, including Premarket Approval requirements and the emerging Real-Time Clinical Trial (RTCT) framework. In live rodents, dual-compartment monitoring has resolved a reproducible 30–60 minutes plasma-to-ISF lag for doxorubicin at 12-second temporal resolution; calibration-free FFT-EIS interrogation achieves inter-animal coefficients of variation below 12% without individual pre-calibration; and xenonucleic acid backbone substitution has extended continuous in vivo operation to seven consecutive days. Three gaps still separate rodent proof-of-concept work from chemotherapy patients: clinical-context validation, tumor microenvironment calibration, and anthracycline-specific XNA aptamer design.

Abstract: Micro-nonuniformity, as a fundamental natural property, is widespread across a range of microscopic aggregate systems, such as polymer systems, biomacromolecular systems, and nanosystems. However, the construction of micro-nonuniform molecular systems has not yet been realized at the level of organic molecules with well-defined structural compositions. Inspired by the “chemical space” concept, I recently reported a study of the single-molecule mixture state; in this paper, I provide a detailed discussion of micro-nonuniformity and the hypothesis of a “single-molecule mixture state”, and propose a possible experimental approach for testing it.

Abstract: Water exhibits anomalous thermodynamic and structural behavior as it approaches and crosses below its melting point. Modelling this behaviour computationally remains challenging: as temperature decreases, nuclear quantum effects (NQE) become increasingly significant, sampling efficiency deteriorates dramatically, and the choice of computational method critically impacts the accuracy of predicted structural and dynamical properties. This review provides a comprehensive assessment of molecular dynamics methodologies for simulating water at low temperatures, with particular emphasis on the supercooled regime (200--273 K). We examine commonly used methods in ab initio molecular dynamics (AIMD) approaches, and critically evaluate strategies for incorporating nuclear quantum effects through path-integral molecular dynamics (PIMD), ring-polymer MD (RPMD), and centroid MD (CMD); below approximately 250 K the magnitude of nuclear quantum effects, and the sensitivity of structural and dynamical properties to them, grows to the point where classical treatment of the nuclei is no longer adequate. The known limitations of density functional approximations for water structure are assessed in the context of their interplay with NQE treatment, rather than in isolation. Practical considerations, including sampling efficiency and the temperature scaling of path-integral bead counts, are discussed alongside the methods.

Abstract: In an environment where the sensitivity of information classification is handled, the defined classification of documents is essential for the strategic protection of assets and their operational integrity. Critical information systems supporting naval, maritime and defence organizations depend on the correct classification of sensitive information to ensure operational continuity, information security and organizational resilience. This study examines the risks associated with the misclassification of critical documents. The real historical case that occurred between 1971 and 1976, published in 1979, deals with the declassification of several sensitive documents that were exposed to civilians who had no authorization or need to know about such information. These incidents demonstrate that classification or declassification failures were the result of weak procedures, technical limitations, and/or human error. A hypothetical case will be conducted in contrast to the real case to identify the key vulnerabilities in classification processes and the associated risk assessment. Finally, corrective measures and proposals will be made, including control procedures and improvements regarding reviews of important issues. These measures aim to reduce classification or declassification errors and strengthen the overall governance of specific information management.

Abstract: The development of 3D printing high impact denture bases is challenging, as materials exhibiting both high flexural strength/modulus and fracture toughness are required. Nowadays, most of the commercially available 3D printing denture bases contain signifi-cant amounts of crosslinking monomers and therefore behave as brittle materials. In this contribution, urethane dimethacrylate DMA1/(octahydro-4,7-methano-1H-indenyl)methyl acrylate (OMIMA) 1/1 (wt/wt) formulations containing a poly(ɛ-caprolactone)-polydimethylsiloxane-poly(ɛ-caprolactone) (PCL-PDMS-PCL) triblock copolymer (BCP1) and fumed silica SiO₂-NPs were evaluated for DLP 3D printing of frac-ture tough denture bases. The post-curing step was performed at various temperatures (RT, 60°C, 80°C, 100°C and 120°C). This parameter was shown to strongly influence the Tg and mechanical properties of 3D printed materials. A post-curing temperature of 100°C was found to be ideal. Under these conditions, 3D printed materials exhibiting excellent mechanical properties were successfully obtained. Furthermore, the amounts of BCP1 and SiO₂-NPs were varied. The formulation containing 8.0 wt% of BCP1 and 10.0 wt% of SiO₂-NPs was able to fulfill the ISO 20795-1:2013 requirements in terms of flexural strength/modulus and fracture toughness for denture bases with improved impact re-sistance. This material showed better performance than the commercially available for-mulations Printodent® GR-14.2 denture HI and Lucitone Digital PrintTM 3D denture base.