Search Results (1,245)

Cordierite-based ceramics (Mg₂Al₄Si₅O₁₈) were successfully synthesized and comprehensively characterized to evaluate their structural and dielectric behavior for high-temperature electronic applications. Morphological, microstructural and vibrational analyses confirm the high phase purity and structural integrity of the synthesized material. Dielectric measurements reveal high real permittivity (ε′) values at low frequencies and elevated temperatures, mainly attributed to interfacial polarization arising from Schottky-type barriers at grain–grain and surface–volume interfaces, underscoring the crucial influence of heterogeneous interfaces on the dielectric response. The electrical conductivity follows a thermally activated hopping mechanism involving both intra-grain and grain-boundary charge transport. Analysis of the electric modulus formalism provides further insight into relaxation dynamics: the real (M′) and imaginary (M″) components highlight pronounced space-charge effects, with M″ exhibiting a distinct relaxation peak (M″) associated with grain contributions. The systematic shift of this peak toward higher frequencies with increasing temperature indicates enhanced charge-carrier mobility and a strongly thermally activated relaxation process. The frequency-dependent conductivity displays two regimes: a low-frequency plateau corresponding to dc conductivity and a high-frequency dispersive region following a power-law behavior characteristic of hopping conduction, with power-law exponents (α₁ and α₂) markedly lower than unity, confirming the non-Debye character of the relaxation processes. The hopping frequency (ω) increases with temperature, further supporting the thermally activated nature of charge transport. Activation energies extracted from Arrhenius plots of dc conductivity are 0.88 eV for grain boundaries and 0.83 eV for grains, demonstrating that both microstructural regions significantly contribute to the overall conduction process. Full article

The practical application of inorganic ferroelectric fillers in flexible piezoelectric composites is critically constrained by low polarization efficiency and severe interfacial incompatibility with polymer matrices. Herein, we report a multi-level in situ surface modification strategy that simultaneously addresses both limitations. High-purity one-dimensional tetragonal barium titanate nanofibers (BTO NFs) are first synthesized via sol–gel electrospinning combined with a two-step gradient annealing process, which precisely controls phase evolution and preserves structural continuity. To overcome the detrimental acid-induced degradation of BTO NFs during functionalization, a polydopamine (PDA) buffer layer is first conformally coated, followed by the liquid-phase deposition of a conductive polypyrrole (PPy) shell, forming a robust core–shell PPy@PBT NFs architecture. Incorporating only 4 wt% of these multifunctional fillers into a poly(vinylidene fluoride) (PVDF) matrix yields a dramatic enhancement in electromechanical performance. The resulting flexible piezoelectric energy harvesters achieve a piezoelectric coefficient (d₃₃) of 28.7 pC/N, an output voltage of 13 V, and an output current of 0.7 μA, representing substantial improvements over unmodified filler systems. This synergistic enhancement originates from the PDA-mediated interfacial stress transfer and the PPy-induced Maxwell–Wagner polarization intensification, establishing a robust and generalizable paradigm for high-performance flexible piezoelectric composites in self-powered wearable electronics. Full article

Temporomandibular disorders (TMDs) are multifactorial conditions traditionally attributed to excessive mechanical loading on the temporomandibular joint, leading to clinical manifestations ranging from joint sounds to structural deformation. Contributing factors include trauma, occlusal abnormalities, psychological stress, and bruxism. However, immune and molecular alterations associated with early disease activity are not systematically integrated into structure-centered TMD frameworks. Emerging evidence indicates that temporomandibular joint osteoarthritis (TMJOA) involves activation of innate immunity caused by damage-associated molecular patterns (DAMPs) generated through mechanical loading, together with non-antigen-specific adaptive immune responses, including macrophage polarization and T helper 17 (Th17) and regulatory T (Treg) cell imbalance. Inflammatory and mechanical inputs converge through shared signaling modules and mechanoresponsive transcriptional programs, promoting extracellular matrix degradation, fibrotic remodeling, and subchondral bone remodeling. This review synthesizes the current immunopathological and mechanobiological evidence and introduces temporomandibular immunologic disease (TMID) as a mechanism-oriented framework, characterized by a reinforcing cycle between mechanically induced tissue damage and immune activation within the temporomandibular joint (TMJ) microenvironment. TMID complements TMJOA and Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) structural diagnostic categories while excluding antigen-specific autoimmune arthritides such as rheumatoid arthritis, thus functioning as a mechanistic overlay framework for the integration of immuno-mechanical signaling networks in immune-active, mechanically driven TMJ pathology. Full article

Cancer remains a leading cause of morbidity and mortality globally, with current therapies often limited by toxicity, drug resistance, and reduced efficacy in advanced stages. Medicinal plants represent important sources of bioactive compounds (BACs) with anticancer and chemopreventive potential; however, their successful application is strongly influenced by extraction strategies that determine phytochemical recovery and downstream biological activity. This review evaluates solvent-based extraction techniques used to extract BACs from medicinal plants with reported anticancer properties, synthesizing peer-reviewed articles from PubMed and Google Scholar published between 2020 and 2025. Solvent-based methods, including Soxhlet and maceration, were most widely applied due to their operational simplicity and the preservation of structurally diverse metabolites while percolation, decoction, infusion, and hydro-distillation were sparsely utilized. Extraction strategy and solvent polarity emerged as primary factors shaping phytochemical profiles, with phenolics, flavonoids, alkaloids, and terpenoids identified as dominant classes. Reported half maximal inhibitory concentration (IC₅₀) ranged from highly potent (0.12 µg/mL) to weak (30,000 µg/mL), reflecting variability driven by extraction parameters and plant matrix complexity. Anticancer mechanisms commonly involved apoptosis induction, cell-cycle arrest, reactive oxygen species-mediated cytotoxicity, and inhibition of proliferative signaling pathways across breast, cervical, colon, lung, liver, and prostate cancer models. Although solvent-based extraction approaches remain widely used, their context-dependent nature and lack of standardization limit reproducibility. Overall, anticancer and chemotherapeutic efficacy is primarily governed by BAC composition, while extraction methods act as upstream modulators. Future progress requires phytochemical-informed, standardized workflows supported by hybrid extraction systems, AI-assisted optimization, and advanced bioavailability and delivery systems to enable reproducible and clinically relevant translation of plant-derived chemotherapeutics. Full article

The objective of this study was to design and evaluate π-extended 1,8-naphthalimide derivatives as photoinduced electron transfer (PET) optical sensors for protons and metal cations, with emphasis on the role of heterocyclic annulation and receptor–chromophore electronic matching. Benzofuran- and benzodioxin-annulated naphthalimides bearing either a dimethylaminoethyl receptor or a non-donating alkyl substituent at the imide nitrogen were synthesized using tailored synthetic strategies. Their photophysical properties were investigated by absorption and fluorescence spectroscopy, while sensing performance was evaluated by fluorescence titrations. Quantum chemistry calculations were employed to rationalize experimental observations. Benzofuran-annulated derivatives exhibit structured π–π* absorption bands and strong fluorescence, whereas introduction of the receptor induces efficient fluorescence quenching via reductive PET. Protonation or metal ion coordination suppresses PET and leads to pronounced fluorescence enhancement, particularly in the presence of Cu(II) and Sn(II). In contrast, benzodioxin-annulated derivatives display intramolecular charge-transfer absorption bands, large Stokes shifts, and low fluorescence quantum yields in polar media, resulting in a negligible sensing response. Computational results attribute this behavior to an unfavorable energy arrangement of the donor–acceptor orbitals. Overall, the study demonstrates that heterocyclic annulation critically governs the electronic structure and sensing performance of naphthalimide fluorophores, providing guidelines for the rational design of PET-based optical sensors. Full article

The immune system is a pivotal regulator of reproductive physiology, maintaining tissue homeostasis essential for successful pregnancy while contributing to infertility and reproductive disorders when dysregulated. Natural products represent a valuable source of novel immunomodulatory agents. Icariin (ICA), a prenylated flavonoid glycoside isolated from Epimedium species (Horny Goat Weed), has a long-standing traditional use for “invigorating yang,” which modern research attributes to its reproductive function-enhancing properties. This review synthesizes emerging evidence that the beneficial effects of ICA on female and male reproductive health are primarily mediated through its sophisticated immunomodulatory actions on the reproductive–immune axis. We systematically dissect the molecular mechanisms by which ICA reprograms the reproductive immune microenvironment, focusing on its regulation of macrophage polarization, T-helper cell (Th1/Th2/Th17) and regulatory T-cell (Treg) balance, and suppression of key pro-inflammatory signaling pathways (NF-κB, NLRP3 inflammasome, JAK-STAT) in ovarian, uterine, and testicular tissues. This review provides a detailed account of how ICA modulates reproductive disorders via regulating immune responses, with the aim of offering innovative strategies for the design of novel immunomodulatory therapies targeting reproductive diseases. Full article

Amphiphilic cationic lipids based on the 1,4-dihydropyridine (1,4-DHP) scaffold represent a versatile platform for the development of self-assembling delivery systems. In this work, a series of ten new amphiphilic 1,4-DHP derivatives bearing branched ester substituents at the 3,5-positions and quaternized cationic groups at the 2,6-positions were designed and synthesized. The effect of branched ester chain length and branching on nanoparticle formation was investigated. The self-assembling properties of the synthesized amphiphiles were evaluated by dynamic light scattering using an ethanol injection method. All compounds formed positively charged nanoparticles with hydrodynamic diameters ranging from 52 to 439 nm and polydispersity index from 0.194 to 0.452. Amphiphiles 14b–17b with 2-hexyldecyl substituents formed smaller particles, with an average diameter below 100 nm. Several derivatives exhibited good stability over a 14-day storage period at room temperature. To clarify structure–property relationships, lipophilicity (AlogP), polar surface area (PSA), and pK_a values were calculated using Schrödinger computational tools. The compounds displayed high lipophilicity AlogP 8.98–19.32, while PSA values remained within a narrow range. The calculated pK_a values ranged from 7.20 to 10.99. The results demonstrate that both the length and architecture of branched ester chains significantly influence nanoparticle size, homogeneity, and stability, highlighting branched-chain 1,4-DHP amphiphiles as promising synthetic lipid candidates for further development of delivery systems after evaluation of biological properties. Full article

Atherosclerosis is a chronic inflammatory and metabolic disease driven by endothelial dysfunction, immune activation, vascular smooth muscle cell remodeling and aging-associated mitochondrial decline. Although lipid lowering remains the cornerstone of therapy, substantial residual inflammatory risk persists, highlighting the need for integrative regulatory targets. Sirtuin 1 (SIRT1), a NAD⁺-dependent deacetylase, has emerged as a central metabolic sensor linking energy availability to transcriptional control of inflammation, oxidative stress, mitochondrial biogenesis and cellular senescence. Experimental studies across endothelial cells, macrophages and vascular smooth muscle cells consistently demonstrate that SIRT1 activation preserves nitric oxide bioavailability, suppresses ROS-dependent inflammasome signaling, modulates macrophage polarization, inhibits ferroptosis and maintains mitochondrial integrity. These cell-type-specific effects converge to reduce plaque progression and enhance fibrous cap stability in preclinical models. However, SIRT1 activity is hierarchically regulated by AMPK signaling and NAD⁺ availability and is influenced by aging, metabolic dysfunction and environmental stressors, underscoring its context-dependent function. Despite promising mechanistic data, clinical translation remains limited, suggesting that precision modulation strategies may be required. This review synthesizes current evidence and proposes that SIRT1 functions as a metabolic–inflammatory integrator within the atherosclerotic arterial wall, representing a potential but context-sensitive target for future cardiovascular therapies. Full article

Plant-based biomaterials are increasingly recognized as bio-instructive platforms capable of actively modulating immune responses rather than functioning solely as passive structural supports. In this context, the term plant-based refers to photosynthetic biomass-derived platforms, including both terrestrial plants and marine macroalgae, reflecting their shared richness in polysaccharides and secondary metabolites relevant to immune engineering and regenerative medicine. This review critically synthesizes current evidence on plant-derived polysaccharides and phytochemicals, including algal sulfated polysaccharides (fucoidan, alginate, carrageenan, and ulvan), terrestrial plant polysaccharides (e.g., Lycium barbarum and Aloe vera derivatives), polyphenols, and other secondary metabolites such as terpenoids and alkaloids, highlighting their roles as immunomodulators in biomedical contexts. Key mechanisms include macrophage polarization along an M1–M2 continuum, pattern recognition receptor engagement, redox and metabolic regulation, and crosstalk between innate and adaptive immunity, with emphasis on context-dependent signaling and structural heterogeneity. Material design parameters, including molecular weight and chemical functionalization, are critical determinants of immune responses. Advanced delivery systems, such as hydrogels, nanocomposites, phytosomes, and plant-derived extracellular vesicles (EVs), enable improved stability and spatiotemporal control. Applications in wound and musculoskeletal regeneration are discussed alongside translational challenges, including variability, reproducibility, regulatory issues, and the need for standardized characterization and immune validation. Full article

Water vapor sorption in porous activated carbons (PACs) is governed by a complex interplay of pore architecture and surface functionality and often exhibits pronounced adsorption–desorption hysteresis. In this work, chestnut-shell-derived carbons were synthesized via a two-step thermal route—pyrolysis at 550 °C for 120 min followed by KOH activation at either 600 °C or 800 °C for 240 min—and evaluated using a dynamic vapor sorption analyzer to quantify water uptake, hysteresis, and temperature-dependent energetics. Both materials exhibit sigmoidal Type V isotherms, characteristic of cooperative water clustering on hydrophobic carbon surfaces with localized polar sites. At 25 °C, The PAC sample prepared at 800 °C shows a sharper uptake transition and higher total capacity (~0.45 g/g at 90% RH), compared to the broader, more gradual isotherm of the 600 °C sample (~0.17 g/g). Temperature-dependent isotherms collected between 25 °C and 45 °C were fit using the Dubinin–Serpinsky (DS-4) model, yielding good agreement (R² ≈ 0.997) and enabling mechanistic interpretation of primary site adsorption and cooperative cluster growth. Clausius–Clapeyron analysis of ln P versus 1/T at fixed loadings yielded isosteric heats of adsorption (ΔH) decreasing from approximately 45.4 kJ mol⁻¹ at low uptake (0.02 g g⁻¹) to ~43.8 kJ mol⁻¹ at intermediate loading, followed by a slight increase to ~44.2 kJ mol⁻¹ at higher coverage (0.35 g g⁻¹). This trend reflects the transition from strong adsorption at high-energy surface sites to cooperative water clustering and confinement effects within the pore network. These findings highlight the role of activation temperature in modulating sorption mechanisms and energetics, offering practical guidance for tuning biomass-derived carbons for atmospheric water harvesting applications. Full article

Magnetoelectric (ME) materials that exhibit simultaneous coupling between electric polarization and magnetization have attracted significant attention due to their potential technological applications in the emerging generation of multifunctional devices. In this research, Ba_0.85Ca_0.15Ti_0.92Zr_0.08O₃-CoFe₂O₄:x (x = 0.1, 0.2, 0.3% mol) composites were synthesized using solid-state and sol–gel combustion chemical methods to elucidate their ME coupling at ultra-low concentrations of the magnetic phase. Rietveld refinement and Raman spectroscopy results confirm a shift in the morphotropic phase boundary (MPB), evidenced by an increase in the tetragonal phase relative to the orthorhombic structure. High stability of the P4mm and Amm2 symmetries is reached at 1300 °C without diffusion of Fe and Co into the octahedral site. At this temperature, the CoFe₂O₄ spinel structure remains stable without secondary phases. The orthorhombic phase fraction decreases from 55% to 37% as the magnetic phase fraction increases, driven by stress and constraint rather than ionic interactions alone. The Curie temperature decreases from 99 to 90 °C, attributed to the grain-size reduction effect rather than structural disorder. The dielectric permittivity (ε_r) reaches an absolute value of 5070 and progressively decreases with increasing magnetic saturation. An increase in compressive residual stress is observed, which ensures the mechanical stability of the electroceramics. Magnetoelectric (ME) coupling, evaluated through measurements of electric polarization as a function of the magnetic field, shows an increase from 3.8 to 4.9 μC/cm² under a magnetic field of 50 Oe. The composites with x = 0.2 and 0.3 mol% exhibit potential for applications in fast-switching magnetoelectric devices and magnetic field sensors. Full article

Mechanochromism is a phenomenon in which mechanical stimuli change the optical properties of a material, such as its color and emission properties. Various materials exhibiting this behavior have been intensively studied. Mechanochromic materials that exploit liquid crystals have been previously reported. Using liquid crystals, properties different from those of conventional materials, such as anisotropic response and multicolored luminescence due to intermediate aggregation phase stabilization, can be expected. Recently, we reported the preparation and evaluation of the optical properties of liquid-crystalline mechanochromic dyes with cholesterol terminals. The dyes formed gels in some solvents, changed their emission color, and exhibited a friable response without reaching a crystalline state. In addition, film-forming properties, processability, and responsiveness were improved in thin films mixed with polymers. However, the mechanical and thermal stabilities of the gels were low. In this study, a compound similar to the polymerizable unit was synthesized to produce tougher gels. In addition, triblock polymers with a mechanoresponsive dye in the hard segment were synthesized. The xerogel film prepared from the monomer showed an irreversible blue shift in photoluminescent color by mechanical grinding and also exhibited linearly polarized photoluminescence by uniaxial grinding due to force-induced alignment. On the other hand, the xerogel film prepared from the triblock copolymer showed a blue shift in photoluminescent color that can approximately revert to the initial state by thermal annealing, though it showed no anisotropy by uniaxial grinding, indicating that polymerization partially preserves mechanical responsiveness. Full article

Human organoids and organ-on-chip/microphysiological systems (OoC/MPS) are increasingly used as new-approach methodologies for biotoxin assessment. They retain human-relevant tissue organization and enable interpretable analysis of exposure geometry, barrier transport, perfusion, and (when needed) multi-organ coupling. In this review, we synthesize primary evidence across major toxin classes, including bacterial enterotoxins (e.g., cholera toxin, heat-stable enterotoxins, Shiga toxins), mycotoxins (e.g., aflatoxin B1, ochratoxin A, deoxynivalenol), and algal/cyanobacterial toxins (e.g., saxitoxin, domoic acid, microcystins, biliatresone). We emphasize studies that clearly define toxin identity and exposure context and that demonstrate mechanism-critical model competencies under assay conditions. We highlight decision-informative functional endpoints that align with the dominant pathophysiology. These include cystic fibrosis transmembrane conductance regulator (CFTR)-dependent secretion in human enteroids/colonoids, transporter-linked proximal tubular injury in kidney MPS, gut–kidney axis injury from Shiga toxin-producing E. coli in microfluidic systems, and multi-electrode array (MEA) network readouts in human 3D neural tissues. We then summarize best practices that improve cross-study comparability. These include reporting delivered versus nominal exposure, assessing recovery/mass balance and device/material interactions, applying proportional biological qualification (polarity, transporter/enzymatic competence, functional stability), defining a minimal comparable endpoint core, and preserving QIVIVE readiness in reporting. Finally, we outline near-term priorities for the field, including chronic low-dose and mixture designs, harmonized reference panels and acceptance criteria, and fit-for-purpose escalation to coupled OoC/MPS only when perfusion or organ–organ coupling is expected to change the interpretation. Full article

Reactive oxygen species (ROS) and reactive nitrogen species (RNS) are central regulators of monocyte and macrophage biology, shaping their survival, differentiation, migration, and effector functions. In monocytes and macrophages, ROS and RNS arise from endogenous sources, such as mitochondria, NADPH oxidases, and myeloperoxidase, and from exogenous stimuli including pathogens, damaged tissues, and environmental oxidants. These reactive intermediates converge on redox-sensitive pathways such as NF-κB, Nrf2/HO-1, mitochondrial ROS signalling, and the NLRP3 inflammasome, thereby integrating metabolic stress with inflammatory activation. Redox balance is a key determinant of macrophage polarization: heightened ROS and RNS production drives pro-inflammatory M1 programs, whereas tightly regulated oxidative signalling supports M2 phenotypes associated with tissue repair and resolution. In chronic inflammatory disorders, notably atherosclerosis, oxidative stress amplifies monocyte recruitment, foam-cell formation, plaque instability, and maladaptive immunometabolic responses. The aim of this review is to recapitulate the major sources and functions of ROS and RNS in monocytes and macrophages and to synthesize current evidence on how these pathways collectively maintain or disrupt immune homeostasis. We further highlight emerging therapeutic strategies, such as NOX inhibitors, mitochondrial-targeted antioxidants, and Nrf2 activators, that seek to restore redox balance and offer promising avenues for the treatment of cardiovascular and immune-mediated diseases. Full article

The chlorophyll molecule is considered a low-cost material, easy to synthesize, and easily extracted from plant leaves. It exhibits high chemical stability, structural flexibility, and high absorbance ability at the visible range of electromagnetic radiation. In this work, the geometrical, electronic, and optical properties of pure, dissolved, and doped chlorophyll (C1) natural organic dye were computed by density functional theory (DFT) and time-dependent density functional theory (TD-DFT). The solvents considered include water (H₂O), acetone (C₂H₆O), dichloromethane (CH₂Cl₂), chloroform (CH₃Cl), and dimethyl-sulfoxide (DMSO) (C₂H₆OS). The solar photovoltaic parameters, such as light-harvesting efficiency (LHE), oscillation strength (f), free energy of electron injection (${\Delta \mathrm{G}}_{\mathrm{I}\mathrm{n}\mathrm{j}.}$) and regeneration (${\Delta \mathrm{G}}_{\mathrm{R}\mathrm{e}\mathrm{g}.}$), open-circuit voltaic (V_OC), and efficiency ($\eta$), were also investigated. The evaluated energy gap slightly shifted from 1.920 eV to 1.980 eV based on the solvent polarity, while the UV-Visible absorption spectrum red-shifted from 422.3 nm to 439.8 nm, improving the overall efficiency up to 21.5% in DMSO solvent. The (LHE) and (${\Delta \mathrm{G}}_{\mathrm{I}\mathrm{n}\mathrm{j}.}$) properties regarding Cl molecules improved up to 69.1% and −1.384 eV when dissolved in chloroform and DMSO solvents, respectively. Doping C1 molecule via metal transition atoms such as zinc (Zn), nickel (Ni) and copper (Cu) further modified the optical and photovoltaic performance. Doped C1 molecule via Cu atom shows the best photonic results, including the highest open-circuit voltage (V_oc) and conversion efficiency ($\mathrm{Ƞ}$), while the Ni-doped C1 dye displays the longest lifetime, 1.699 µs, and the highest electronic coupling constant, 1.975 eV; thus, it has the superior photovoltaic performance. These results demonstrate that both solvents and transition metal atom modification significantly improve C1 performance, making metal-doped C1 a promising low-cost and eco-friendly sensitizer for dye-sensitized solar cells (DSSCs). Full article