Search Results (1,151)

Chlorophyll content is a key determinant of photosynthetic efficiency and grain yield in rice (Oryza sativa L.), while premature chlorophyll degradation during the reproductive stage can markedly reduce crop productivity. However, the genetic basis underlying chlorophyll degradation and its environmental responsiveness remains incompletely understood. In this study, an F₂ population derived from a cross between the japonica cultivar Shennong0530-9 and the indica cultivar Habataki was used to identify quantitative trait loci (QTLs) associated with chlorophyll content at different developmental stages. A total of 22 QTLs were detected; among these, qCD2 consistently showed a major and stable effect on chlorophyll degradation after heading. Fine mapping using residual heterozygous lines delimited qCD2 to a 54.0 kb genomic interval on the short arm of chromosome 2 containing nine predicted genes. Near-isogenic lines (NIL-qCD2) carrying the qCD2 allele exhibited accelerated chlorophyll loss after heading, accompanied by disrupted chloroplast ultrastructure, reduced photosynthetic capacity, and significant decreases in grain yield and grain quality compared with the recurrent parent. Furthermore, the chlorophyll-deficient phenotype became progressively more severe under elevated temperature conditions, indicating that the phenotypic effect associated with qCD2 is temperature sensitive. Consistent with these physiological changes, the expression patterns of genes involved in chloroplast development, photosynthesis, and leaf senescence were significantly altered in NIL-qCD2. Collectively, these results identify qCD2 as a stable QTL associated with chlorophyll degradation during the reproductive stage and provide a foundation for future identification of the causal gene, providing valuable genetic resources for the molecular breeding of rice with improved photosynthetic efficiency, grain yield, and grain quality. Full article

Background: Terminal sterilization is a regulatory requirement for most medical devices. However, conventional sterilization methods can compromise temperature-sensitive and biologically reactive components. This study evaluates the sterilization efficacy and preliminary material compatibility of a novel room-temperature sterilization modality using gaseous nitric oxide (NO). Methods: NO was delivered using standardized Sterile Solution^® (Sterile State Inc., Grand Rapids, MI, USA). To characterize microbial inactivation kinetics, the decimal reduction time (D-value) of commercial biological indicators (BIs), Bacillus atrophaeus Apex^® Discs, was determined in accordance with ISO 11138. BIs were exposed to NO at ambient temperature (18.9–22.0 °C). D-values were calculated using both the survivor curve method (Holcomb–Spearman–Karber) and the fraction-negative method (Stumbo–Murphy–Cochran). Material compatibility was evaluated across four primary medical device and packaging plastics, including polyethylene (PE), poly(ethylene terephthalate) (PET), polypropylene (PP), and polyvinyl chloride (PVC)), representing 70% of the industry market share. After exposure to NO sterilization cycles, mechanical and chemical properties were characterized using tensile testing (ASTM D882-18) and Fourier-transform infrared (FTIR) spectroscopy relative to unexposed controls. Results: The calculated D-values ranged from 1.31 (78.7 min) to 1.34 h (80.4 min) across both analytical methods, corresponding to an estimated 6-Log reduction in Bacillus atrophaeus BIs in approximately 8 h. Meanwhile, plastics exposed to the NO sterilization cycle showed no significant changes in mechanical or chemical properties. Conclusions: These findings demonstrate that NO sterilization achieves semi-Log-linear inactivation of a widely accepted BI and represents a promising alternative to conventional gaseous sterilization methods such as ethylene oxide (EtO). By achieving a reliable sterility assurance level under mild ambient conditions without adversely affecting the physicochemical properties of commonly used plastic materials, NO sterilization may offer a practical solution for thermosensitive and delicate medical devices. Full article

Alveolar bone resorption after tooth extraction complicates subsequent dental implant placement. OsteoBiol^® GTO^® (Tecnoss^®, Giaveno, Italy) is an innovative pre-hydrated heterologous collagenated bone mix blended with a thermosensitive copolymer (OsteoBiol^® TSV Gel) that has demonstrated osteoconductive properties. Despite direct contact with blood vessels upon socket filling, its pro-angiogenic potential has not been directly investigated on endothelial cells. Thus, in this study, an in vitro model, consisting of the EA.hy926 endothelial cell line exposed to different OsteoBiol^® GTO^® soaking preparations [original soaking (OS), centrifuged soaking (CS), and diluted soaking (DS)] at multiple concentrations (1, 5, 10, and 20 mg/mL) was established to identify optimal experimental conditions and characterize the underlying molecular mechanisms. Cell viability and collagen release quantification led to the selection of 10 mg/mL OS as the most suitable condition. Under this condition, OsteoBiol^® GTO^® induces an early increase in Cyclooxygenase-2 (COX-2) protein expression and Prostaglandin E-2 (PGE2) secretion, followed by upregulation of Vascular Endothelial Growth Factor (VEGF) protein expression and phosphorylation of Endothelial Nitric Oxide Synthase (eNOS) at serine 1177. The tube formation assay confirmed the pro-angiogenic functional outcome. These results suggest an association between the pro-angiogenic response of endothelial cells to OsteoBiol^® GTO^® and modulation of the COX-2/PGE2/VEGF axis. This effect could be attributed to collagen accumulation in the OS, thereby representing a novel and promising pro-angiogenic mechanism with potential implications for wound healing and guided bone regeneration following tooth extraction. Full article

Potato (Solanum tuberosum L.) tuberization is a complex developmental transition in which a subterranean stolon is converted into a starch-accumulating tuber. This process is governed by long-distance systemic signals, local hormonal dynamics, and extensive metabolic reprogramming. Recent advances have extended our understanding beyond the classical photoperiodic model, revealing the importance of chromatin remodeling, mRNA N⁶-methyladenosine (m⁶A) epitranscriptomic modifications, and a developmentally regulated shift in phloem unloading pathways. Here, we synthesize these multilayered regulatory networks into an integrated framework. We also examine the thermosensitivity of the mobile tuberigen signal under climate warming, assess the genetic challenges imposed by autotetraploidy and gene dosage, and discuss recent progress in diploid hybrid breeding strategies. In addition, we highlight emerging evidence for the roles of mechanoperception and rhizosphere microbiota as previously overlooked modulators of tuberization. Finally, we outline how these fundamental insights can be translated into breeding pipelines, with a focus on genome editing of cis-regulatory elements and the design of F1 hybrid cultivars. This review provides a conceptual roadmap for engineering climate-resilient, high-yielding potato cultivars to support global food security. Full article

Ultra-supercritical (USC) steam turbines combine severe steam conditions with increasingly frequent start-up, shutdown, and load-following operations. Their main steam valves must preserve pressure boundary integrity, sealing, and rapid actuation while non-uniform heating, creep, cyclic plasticity, oxidation, wear, and contact redistribution alter component geometry. However, the relevant evidence remains fragmented across alloy development, component thermo-mechanics, valve aerodynamics, and lifetime monitoring. This short, mechanism-oriented review integrates these domains through a material structure–function framework in which deformation relative to assembly clearance governs jamming risk. It synthesizes evidence on heat-resistant body and surface materials, 9–12% Cr steel stability, weldability and repair sensitivity, and cold, warm, and hot start-up histories. It also evaluates creep–fatigue interaction, contact, flow-induced vibration, multi-physics modeling, validation, uncertainty, monitoring, and digital twins. The synthesis shows that neither peak equivalent stress nor steady-state temperature alone can establish functional reliability. Credible assessment requires temperature-dependent material data, realistic steam-side heat transfer, cyclic constitutive behavior, initial and residual clearances, manufacturing and assembly tolerances, state-dependent friction, uncertainty analysis, and corroborating plant or inspection evidence. The most consequential research needs are valve-level validation datasets, thermal contact testing, function-oriented life criteria, and uncertainty-aware digital twins that jointly inform materials, geometry, and transient operation. Full article

Accurate prediction of the temperature field around shallow-buried freezing pipes is important for the design and assessment of artificial ground freezing systems in shallow tunnel and underground structure construction. This study develops a semi-analytical series solution for the steady-state temperature field around a twin-pipe freezing unit in a semi-infinite domain under Dirichlet boundary conditions. The model assumes steady-state heat conduction in homogeneous and isotropic soil with prescribed pipe wall and ground surface temperatures; transient phase change, groundwater seepage, and thermo-hydro-mechanical coupling are not considered. Conformal mappings are used to transform the original semi-infinite and eccentric domains into bounded circular domains. The temperature field is decomposed into two subproblems by superposition, and the corresponding general solutions are expressed using Fourier series. The unknown coefficients are determined through boundary discretization and the solution of a finite linear algebraic system. The proposed method is compared with ANSYS Fluent results in the transformed domain at six selected points, yielding a pointwise NRMSE of 0.758% at a truncation order of 20. Parametric analyses further illustrate the qualitative sensitivity of the calculated temperature field to different ground surface temperatures, pipe radii, burial depths, and pipe spacings. The proposed method provides a preliminary semi-analytical framework for rapid quasi-steady temperature field estimation and qualitative parameter sensitivity analysis of shallow-buried twin-pipe artificial ground freezing systems. Full article

Caffeine is a promising active for topical pharmaceutical and cosmetic applications; however, its hydrophilic nature can limit passive transport across the stratum corneum and reduce local retention. Although nanoparticle-loaded dissolving microneedles have been explored, few systems combine a hollow porous carrier, a lipid coating, and a polysaccharide matrix within a single controlled-release platform. This study developed thermosensitive dissolving microneedles (DMNs) incorporating caffeine-loaded liposome-coated hollow mesoporous silica nanoparticles (ULp-Caf@HMSNs). Sodium alginate–κ-carrageenan matrices, with and without stearic acid modification, were evaluated for their effects on thermal behavior, mechanical strength, and caffeine release. HMSNs showed a hollow mesoporous structure and high specific surface area, while FTIR supported successful incorporation of the formulation components. Liposome coating increased particle size while maintaining nanoscale dimensions. Hot-stage microscopy showed temperature-dependent structural changes at approximately 33–35 °C, with lower apparent transition temperatures in stearic acid-containing formulations. All DMNs exhibited compression forces comparable to mechanically competent DMNs, with NaAlg–κ-car systems reaching 14.3–15.1 N per array. Free-caffeine DMNs followed non-Fickian release, whereas ULp-Caf@HMSN-containing formulations followed Higuchi diffusion-controlled release and showed slower caffeine release. Stearic acid did not consistently improve release performance. The novelty of this work lies in integrating a hollow silica reservoir, a liposomal coating, and an alginate–κ-carrageenan microneedle matrix within one platform. Overall, the system provides a basis for further evaluation in controlled topical or transdermal caffeine delivery. Full article

Photothermally induced hyperthermia with safe, localized, and effective optical power densities is critically important to patients’ comfort level and safety in cancer therapeutic applications. This research study explores cesium tungsten oxide (CsWO₃) NPs as the kernel of a drug-release nanocomposite that releases a cancer drug upon near-infrared irradiation. The nanocomposite was functionalized with thermo-sensitive hydrogels to upload Doxorubicin and Cisplatin, characterized and assessed for its therapeutic efficacies against the cancerous gastric cells and hepatocytes. The nanocomposites reached 40.5 °C in 15 min when irradiated at 500 mW/cm² and respectively yielded 37% and 41% of release rates for Doxorubicin and Cisplatin over a span of 24 h. The analysis indicates that the nanocomposites effectively reduced the survival rates of the hepatocellular carcinoma cells and the cancerous gastric cells by 24.2% and 23.9% at 400~500 mW/cm² while minimizing the damaging effects on the healthy cells by 24.3% when compared to those of pure substances. This work highlights the great potential of CsWO₃ NP for constructing drug-release platforms with minimal optical power density and safe NP concentration. Full article

The increasing demand for sustainable bitumen modifiers has stimulated interest in bio-based materials capable of improving binder performance while reducing environmental impact. This study investigates the influence of corn starch on the thermo-oxidative aging kinetics of paving-grade bitumen. Unmodified 50/70 bitumen and binders containing 4, 6 and 8 wt.% corn starch were subjected to laboratory aging at 100 °C and 140 °C for up to 120 h. The aging process was evaluated using dynamic viscosity measurements, FTIR spectroscopy and Multiple Stress Creep Recovery (MSCR) testing. The obtained results demonstrated that corn starch significantly affected both the rate and temperature dependence of aging. The effect of corn starch was strongly dependent on both the aging temperature and modifier dosage, indicating that starch does not uniformly inhibit all aging processes but rather modifies their kinetics in a process-specific manner. Increasing the aging temperature from 100 to 140 °C accelerated the viscosity growth by approximately 9–11 times, depending on the binder composition. The apparent rate constants for carbonyl formation ranged from 9 × 10⁻⁶ to 7 × 10⁻⁵ h⁻¹ for the reference binder and from 1 × 10⁻⁵ to 5 × 10⁻⁵ h⁻¹ for starch-modified binders. The calculated apparent activation energies varied between 1.31 and 67.6 kJ mol⁻¹, confirming that starch altered the temperature sensitivity of oxidation and structural transformation reactions. Among the investigated formulation (4–8 wt.% corn starch), the binder containing 4 wt.% corn starch exhibited the most favorable balance between aging resistance and production cost. Overall, the results demonstrate that corn starch modifies rather than universally inhibits bitumen degradation, with the optimum performance depending on the investigated aging parameter, modifier dosage and aging temperature, with 4 wt.% providing the most favorable overall balance between chemical aging behavior, rheological performance and production cost. Full article

Hybrid nanofluids raise the thermal output of evacuated-tube solar collectors, but the heat-transfer gain comes at the cost of friction and pumping power, so the working fluid must be chosen in line with a constrained thermo-hydraulic criterion. Its design is posed here as a constrained single-objective optimisation over the hybrid pair, base fluid, weight fraction, component share and flow rate. A variance-based screening of a 54,432-run full-factorial dataset reduces the design space from eight variables to five, justified by the invariance of the optimal hybrid pair across thirty-six operating points. Gradient-boosted surrogates for the four state and constraint responses (efficiency, pumping power, Reynolds number and outlet temperature) reproduce the simulator to held-out coefficients of determination of 0.9998–1.0000; the performance-criterion surrogate has a lower global coefficient of determination (0.46) and is assessed by top-region ranking accuracy. The reduced problem is solved with a selection hyper-heuristic over twelve operators, pairing an upper-confidence-bound selector with late-acceptance hill-climbing. Under Friedman-, Nemenyi- and Holm-corrected Wilcoxon testing, it ranks within the leading statistically indistinguishable group, but is not separable from a random-selection ablation, locating its value in robustness rather than adaptivity; furthermore, it attains the grid-reference optimum within 0.40 percent. The criterion optimum is an Al₂O₃-Cu suspension in ethylene-glycol and water at three percent loading; the constrained-efficiency optimum reaches a surrogate thermal efficiency of 0.760, cross-checked against a grid-reference value of 0.762 and a reconstructed-model value of 0.760, conditional on the supplied reduced-order model and its single-tube dataset convention. The constrained-efficiency objective is treated as the primary design objective, while the performance criterion is reported as a secondary screening index that characterises the additive rather than selecting the operating fluid. Full article

Process heating for sensitive fluids requires a sophisticated balance of efficiency and thermal control. This study assesses the efficiency of a singular active-surface flow box delivering high-precision, volumetric energy transport. Entropy generation analysis coupled with conjugate heat transfer can be effectively conducted using three-dimensional CFD to monitor the local irreversibilities stemming from direct contact with the active surface (heat transfer) and macro-steady flow structures (viscous dissipation). The entropy generation metric proposed, based on a Brinkman number, demonstrates that the global entropy generated grows less than linearly with the applied thermal power, while only a slight decrease is found with the increasing flow rate, for the two fluids examined. We conclude that integrating entropy generation analysis within a CFD framework is a robust tool for optimizing heaters for precision processing. For sensitive fluids such as liquid foods, this methodology is particularly valuable, as it directly links thermodynamic efficiency to quality retention by limiting excessive local temperatures. This research advances the development of entropy-informed thermo-fluid systems, offering a clear pathway for the design of high-performance, precision heating devices. Full article

The qualitative evolution of SARA fractions during asphalt binder aging is well established, but further validation is needed to demonstrate whether automated HPLC-SARA analysis can provide repeatable compositional indicators for systematic aging studies. In this work, the applicability of a previously optimized automated high-performance liquid chromatography (HPLC) workflow for saturate, aromatic, resin, and asphaltene (SARA) fractionation was evaluated for the monitoring of thermo-oxidative aging. Four penetration-grade asphalt binders were subjected to short-term aging and multiple long-term aging cycles, and the resulting SARA distributions were used to calculate the colloidal instability index (I_c). Fourier-transform infrared spectroscopy (FTIR) was used as an independent reference technique to evaluate carbonyl and sulfoxide oxidation indices. The automated HPLC-SARA method provided repeatable compositional indicators across all asphalt binders and aging conditions. As expected, aromatics progressively decreased whereas asphaltenes increased, while saturates showed only limited variations and resins behaved as an intermediate operational fraction. More importantly, I_c increased consistently with aging and showed a strong correlation with the FTIR carbonyl index (R² = 0.84 when all asphalt binders and aging conditions were considered), whereas the sulfoxide index showed a more asphalt binder-dependent response. These results demonstrate that automated HPLC-SARA analysis can provide aging-sensitive compositional and colloidal indicators that are chemically consistent with independent FTIR oxidation markers. The proposed workflow represents a complementary tool for asphalt binder aging research and may support future studies aimed at linking compositional evolution with rheological and durability-related properties. Full article

Objective: This study aimed to enhance wound healing by developing a delivery platform that combines camel milk-derived extracellular vesicles (CM-EVs) with a thermosensitive chitosan/Poloxamer 407 hydrogel (CM-EVs–Gel), addressing the challenges of instability, poor skin penetration, and burst release associated with EVs. Methods: CM-EVs were isolated and analyzed for size, markers, and protein content. A thermosensitive hydrogel was created and infused with CM-EVs. Its gelation, injectability, and release kinetics (using the Higuchi model) were tested. Safety was evaluated through ocular irritation and 28-day skin toxicity in rabbits. Wound healing effectiveness was tested in rats with full-thickness wounds, comparing CM-EVs–Gel, a blank hydrogel, and untreated controls. Results: CM-EVs had an average size of 108.5 nm and expressed CD63, CD81, and Alix. The hydrogel solidified at 37 °C within 10 min and followed the Higuchi model for diffusion-controlled release (R² = 0.974), releasing 81.7% of EVs over 48 h without toxicity. In rats, CM-EVs–Gel achieved 76.31% wound closure by day 6 and 94.7% by day 15, outperforming blank hydrogel (48.77% and 82.1%) and untreated controls (43.14% and 72.3%) (p < 0.01). Histology showed improved re-epithelialization, collagen deposition, and angiogenesis. Conclusions: This study shows that integrating biogenic particle engineering with optimized hydrogel systems allows for controlled release, safety, and enhanced wound healing. Despite missing free EV controls, full rheological data, and mechanistic insights, it highlights comprehensive delivery strategies from particle design to system performance, aligning with the Special Issue’s focus. Full article

The oral cavity represents one of the most demanding operating environments for biomedical coatings, subjecting materials to constant masticatory shear and tribological stress, dynamic temperature fluctuations, salivary enzymatic activity, and continuous fluid turnover that collectively challenge coating adhesion, durability, and longevity. Thermosensitive hydrogels that undergo reversible sol–gel transitions near body temperature offer a uniquely versatile platform for in situ coating formation on complex oral surfaces, enabling minimally invasive application and conformal coverage of irregular anatomical structures—from periodontal pockets and root canal systems to extraction sockets and bone defects. This review examines the application of thermo-sensitive hydrogel coatings across six major oral disease categories: periodontitis, peri-implantitis, bone defects, endodontic diseases, extraction wounds, and oral cancer. We further discuss practical hurdles facing clinical translation, noting that sterilization often degrades these materials, mechanical properties may prove inadequate under masticatory loads, and long-term biosafety data remains limited. This review critically evaluates how these smart coatings can bridge the gap between laboratory innovation and clinical application, offering insights to guide the development of next-generation precision therapies for oral diseases. Full article

Efficient heat transfer is essential for the in-situ conversion of steeply dipping oil shale reservoirs. In this study, a superheated steam-driven integrated multi-branch well system was proposed, and a coupled thermo-hydro-chemical-mass transport model considering reservoir anisotropy was established in COMSOL Multiphysics-5.6 to investigate heat transfer characteristics and evaluate the effects of key engineering parameters. The numerical model was validated through comparison with an analytical solution and previously published numerical results. The results show that superheated steam preferentially migrates through hydraulic fractures and bedding-parallel high-permeability pathways, resulting in anisotropic heat transfer. Continuous steam injection gradually forms a connected high-temperature region, and most of the reservoir exceeds 500 °C after approximately 600 days. Compared with the conventional well arrangement, the proposed well system achieves more uniform reservoir heating and enlarges the effective pyrolysis region. Parametric analysis indicates that the highest thermal performance among the investigated cases is obtained with a heating well length of 22.5 m, while increasing the inter-well angle, fracture number, and fracture width enhances heat transfer and kerogen conversion. Among the investigated cases, the configuration with three hydraulic fractures achieves the best performance, with the high-temperature region (>500 °C) exceeding 80% of the reservoir after 400 days and a cumulative hydrocarbon production of approximately 4.7 × 10⁷ mol. Sensitivity analysis further demonstrates that fracture-related parameters exert a greater influence on reservoir thermal performance than heating well length and inter-well angle. These findings provide theoretical guidance for the design and performance evaluation of integrated multi-branch well systems for the efficient in-situ conversion of steeply dipping oil shale reservoirs. Full article