Search Results (10,310)

Grammatophyllum speciosum Blume is an endangered wild orchid with medicinal properties. In this research, we propagated G. speciosum from vegetative organs grown under aseptic conditions. Subsequently, salinity stress was applied at the plantlet stage to investigate its effect on the accumulation of bioactive compounds. Half-strength Murashige and Skoog (½ MS) medium supplemented with a combination of 1 mg of L⁻¹ 1-naphthaleneacetic acid (NAA) and 0.5 mg of L⁻¹ 6-benzylaminopurine (BAP) proved to be a more suitable medium for shoot formation (32.33 ± 2.52 shoots per explant). The protocorm-like bodies, derived from embryogenic callus, were transferred into a temporary immersion bioreactor (TIB) system; 10-min of immersion every 3 h enhanced the maximum number of shoots, shoot height, and the fresh growth index (127.00 ± 2.16, 5.00 ± 0.51 cm and 4.26 ± 0.52, respectively). The proliferated plantlets from the TIB system successfully rooted in Vacin and Went medium. Furthermore, the plantlets were maintained in ½ MS medium supplemented with sodium chloride (NaCl) (0, 50, 100 or 200 µM) under a white light-emitting diode for 72 h to determine the total phenolic content (TPC) in the in vitro cultures. The TPC was highest in the medium with 100 µM of NaCl (111.06 ± 2.24 mg gallic acid equivalent g⁻¹ dry weight), the diphenyl picrylhydrazyl antioxidant activity was 24.50 ± 0.76% and ferric-reducing antioxidant power values were in the range 2441.79 ± 1.21 to 2491.96 ± 3.23 µM ascorbic acid equivalent g⁻¹ dry weight. The G. speciosum extracts showed antibacterial activity against acne pathogens, with minimum inhibitory concentration and minimum bactericidal concentration values in the ranges 6.4–12.8 mg mL⁻¹ and 12.8–25.6 mg mL⁻¹, respectively. Full article

This work examines the effect of gadolinium (Gd) promotion on nickel-based SBA-16 catalysts for the dry reforming of methane (DRM), with the goal of improving syngas production by optimizing catalyst composition and operating conditions. Catalysts with varying Gd loadings (0.5–3 wt.%) were synthesised using co-impregnation. XRD, N₂ physisorption, FTIR, XPS, and H₂-TPR–CO₂-TPD–H₂-TPR were used to examine the structural features, textural properties, surface composition, and redox behaviour of the catalysts. XPS indicated formation of enhanced metal–support interactions, while initial and post-treatment H₂–TPR analyses showed that moderate Gd loadings (1–2 wt.%) maintained a balanced distribution of reducible Ni species. The catalysts were tested for DRM performance at 800 °C and a gas hourly space velocity (GHSV) of 42,000 mL g⁻¹ h⁻¹. 1–2 wt.% Gd-promoted catalysts achieved the highest H₂ (~67%) and CO yield (~76%). Response surface methodology (RSM) was used to identify optimal reaction conditions for maximum H₂ yield. RSM predicted 848.9 °C temperature, 31,283 mL g⁻¹ h⁻¹ GHSV, and a CH₄/CO₂ ratio of 0.61 as optimal, predicting a H₂ yield of 96.64%, which closely matched the experimental value of H₂ yield (96.66%). The 5Ni–2Gd/SBA-16 catalyst exhibited minimal coke deposition, primarily of a graphitic character, as evidenced by TGA–DSC and Raman analyses. These results demonstrate the synergy between catalyst design and process optimization in maximizing DRM efficiency. Full article

Dry reforming of methane and ethanol is a promising catalytic process for the conversion of carbon dioxide and hydrocarbon feedstocks into synthesis gas (H₂/CO), which serves as a key platform for the production of fuels and chemicals. Over the past decade, substantial progress has been achieved in the design of catalysts with enhanced activity and stability under the demanding conditions of these strongly endothermic reactions. This review summarizes the latest developments in catalyst systems for DRM and EDR, including Ni-based catalysts, perovskite-type oxides, MOF-derived materials, and high-entropy alloys. Particular attention is given to strategies for suppressing carbon deposition and preventing metal sintering, such as oxygen vacancy engineering in oxide supports, rare earth and transition metal doping, strong metal–support interactions, and morphological control via core–shell and mesoporous architectures. These approaches have been shown to improve coke resistance, maintain metal dispersion, and extend catalyst lifetimes. The review also highlights emerging concepts such as multifunctional hybrid systems and innovative synthesis methods. By consolidating recent findings, this work provides a comprehensive overview of current progress and future perspectives in catalyst development for DRM and EDR, offering valuable guidelines for the rational design of advanced catalytic materials. Full article

With the development of technology, many fields have put forward higher requirements for the thermal conductivity of materials in high-temperature environments, for instance, in fields such as heat dissipation of electronic devices, high-temperature sensors, and thermal management. As a potential high-performance thermal management material, studying the thermal conductivity of graphene at high temperatures is of great significance for expanding its application range. In this study, high-quality suspended graphene was prepared through PDMS dry transfer, which can effectively avoid the binding and influence of the substrate. Based on the calculation model of the thermal conductivity of suspended graphene, the model was modified accordingly by measuring the attenuation coefficient of laser power. Combined with the temperature variation coefficient of suspended graphene measured experimentally and the influence of laser power on the Raman characteristic peak positions of graphene, the thermal conductance of suspended graphene with different layers under high-temperature conditions was calculated. It is conducive to a further in-depth understanding of the phonon scattering mechanism and heat conduction process of graphene at high temperatures. Full article

Polyploidization is a rapid breeding strategy for producing new varieties with superior agronomic traits. Kenaf (Hibiscus cannabinus L.), an important fiber crop, exhibits high adaptability to diverse stress conditions. However, comprehensive studies on polyploid induction, screening, and genetic identification in kenaf remain unreported. This study first established an optimal tetraploid induction system for diploid kenaf seeds using colchicine. The results showed that a 4-h treatment with 0.3% colchicine yielded the highest tetraploid induction rate of 37.59%. Compared with diploids, tetraploid plants displayed distinct phenotypic and physiological characteristics: dwarfism with shortened internodal distance, increased stem thickness, larger and thicker leaves with deeper green color and serration, as well as enlarged flowers, capsules, and seeds. Physiologically, tetraploid leaves featured increased chloroplast numbers in guard cells, reduced stomatal density, and larger pollen grains, elevated chlorophyll content. Further analyses revealed that tetraploid kenaf had elevated contents of various trace elements, enhanced photosynthetic efficiency, prolonged growth duration, and superior agronomic traits with higher biomass (54.54% higher fresh weight, 79.17% higher dry weight). These findings confirm the effectiveness of colchicine-induced polyploidization in kenaf, and the obtained tetraploid germplasm provides valuable resources for accelerating the breeding of elite kenaf varieties with improved yield and quality. Full article

Background/Objectives: Lifitegrast is a recent therapeutic agent provoking scientific and regulatory interest due to its outstanding safety profile and high efficacy in the treatment of dry eye disease. Methods: Herein we employ NMR spectroscopy and mass spectrometry to investigate the weak spots of lifitegrast under standard to extreme stress conditions, resulting in the characterization of three known and nine new degradation products (of which DP7 presented the greatest structural challenge, but was eventually determined as C10 hydroxy derivative, warranting a revision of its previously suggested structure). Results: The first weak spot is identified as a N1–C40 amide bond, and its high susceptibility to hydrolysis is explained through computational DFT analysis. The second and third weak spots are elucidated through bond dissociation energy (BDE) calculations which highlighted the oxidative vulnerabilities of both the piperidine and benzofuran ring. Conclusions: Additionally, two degradation products, observed in initial, extended, and targeted oxidative forced degradation studies, were selected for in silico toxicity assessment and were predicted to have toxicity profiles comparable to or lower than lifitegrast. Full article

Outdoor thermal comfort in tropical cities is increasingly threatened by rapid urbanization, high humidity, and insufficient climate-sensitive planning. Despite numerous studies on urban heat mitigation, there is a lack of empirical and numerical research that evaluates the synergistic application of bioclimatic strategies under humid tropical conditions. This paper addresses this gap by analyzing the combined effect of arborization, dry mist systems, water bodies, and sprinklers on outdoor thermal comfort at the Víctor Levi Sasso Campus of the Technological University of Panama. We hypothesized that synergistic application of these strategies provides greater thermal comfort improvements than isolated interventions. The central research question guiding this study was: To what extent can combined bioclimatic strategies enhance outdoor thermal comfort compared to individual strategies in humid tropical environments? To answer this, a hybrid methodology was employed, integrating ENVI-met dynamic simulations with in situ measurements and thermal comfort surveys based on the physiological equivalent temperature (PET) index and subjective comfort scales. The results demonstrate that combined strategies achieve superior reductions in mean radiant and surface temperatures while improving subjective comfort perceptions, highlighting their potential for context-sensitive urban design in tropical regions. Full article

Seawater intrusion into coastal river systems poses increasing challenges for freshwater availability and estuarine ecosystem integrity, especially under evolving climatic and anthropogenic pressures. This study presents a multidisciplinary investigation of marine intrusion dynamics within the Magra River estuary (Northwest Italy), integrating field monitoring, isotopic tracing (δ¹⁸O; δD), and multivariate statistical modeling. Over an 18-month period, 11 fixed stations were monitored across six seasonal campaigns, yielding a comprehensive dataset of water electrical conductivity (EC) and stable isotope measurements from fresh water to salty water. EC and oxygen isotopic ratios displayed strong spatial and temporal coherence (R² = 0.99), confirming their combined effectiveness in identifying intrusion patterns. The mass-balance model based on δ¹⁸O revealed that marine water fractions exceeded 50% in the lower estuary for up to eight months annually, reaching as far as 8.5 km inland during dry periods. Complementary δD measurements provided additional insight into water origin and fractionation processes, revealing a slight excess relative to the local meteoric water line (LMWL), indicative of evaporative enrichment during anomalously warm periods. Multivariate regression models (PLS, Ridge, LASSO, and Elastic Net) identified river discharge as the primary limiting factor of intrusion, while wind intensity emerged as a key promoting variable, particularly when aligned with the valley axis. Tidal effects were marginal under standard conditions, except during anomalous events such as tidal surges. The results demonstrate that marine intrusion is governed by complex and interacting environmental drivers. Combined isotopic and machine learning approaches can offer high-resolution insights for environmental monitoring, early-warning systems, and adaptive resource management under climate-change scenarios. Full article

To address the challenge of long-term stiffness retention of subgrades in humid–hot climates, this study evaluates expansive soil stabilized with construction and demolition waste (CDW), focusing on the resilient modulus (M_r) under coupled stress states and wetting–drying histories. Basic physical and swelling tests identified an optimal CDW incorporation of about 40%, which was then used to prepare specimens subjected to controlled. Wetting–drying cycles (0, 1, 3, 6, 10) and multistage cyclic triaxial loading across confining and deviatoric stress combinations. M_r increased monotonically with both stresses, with stronger confinement hardening at higher deviatoric levels; with cycling, M_r exhibited a rapid then gradual degradation, and for most stress combinations, the ten-cycle loss was 20%–30%, slightly mitigated by higher confinement. Grey relational analysis ranked influence as follows: the number of wetting–drying cycles > deviatoric stress > confining pressure. A Lytton model, based on a modified prediction method, accurately predicted M_r across conditions (R² ≈ 0.95–0.98). These results integrate stress dependence with environmental degradation, offering guidance on material selection (approximately 40% incorporation), construction (adequate compaction), and maintenance (priority control of early moisture fluctuations), and provide theoretical support for durable expansive soil subgrades in humid–hot regions. Full article

In the Mediterranean basin, olive cultivation occupies the largest share of agricultural land, due to the region’s favorable soil and climatic conditions. However, the intensification of farming systems has had negative environmental impacts, for which diversified approaches such as agroforestry offer a potential solution. The objective of the present study was to determine the growth of barley, triticale, and pea as cover crops, as well as the respective intercrops in olive orchards and their productivity. The results showed that the intercropping of pea with barley and triticale had the highest yields in dry biomass compared to the other treatments, while barley monoculture recorded the highest yield in terms of grain. The findings demonstrated that intercropping enhances resource-use efficiency, particularly in terms of land productivity, Radiation-Use Efficiency, and Water-Use Efficiency. However, competitive dynamics varied significantly between species and across years, with pea often exhibiting dominance in biomass production, while cereals showed trade-offs in seed yield components due to shading and interspecific competition. These findings can be used for sustainable intensification strategies, ensuring higher productivity while minimizing external inputs in climate-vulnerable regions. Full article

This article presents studies of surface layers produced by electro-spark deposition (ESD) on cast iron using a W-Ni-Co sintered electrode. To minimize the number of required experiments, a two-factor, five-level Hartley experimental design was chosen. The assessment involved observing the effect of voltage and capacitor capacity during the ESD process (on layer thickness and wear of the sample and counter-sample under technically dry friction conditions). Microscopic and tomographic observations were performed to analyze the thickness and structure of the layers. Image analysis methods were employed to examine the cross-section of the layers. ESD diffusion analyses were performed on the produced layer. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) were performed to characterize the microstructure and composition of the coating. In addition, in order to evaluate the performance properties of tungsten coatings, the tribological tests were also conducted on a TRB³ Ball-on-Disc testing device. Hardness tests confirm an increase in the hardness of cast iron with a tungsten layer by over 400 µHV. The tests showed that higher voltages during the ESD process result in thicker layers and reduced wear of the sample with a tungsten layer at the expense of increased wear of the counter-sample (ball). Full article

Apple pomace, a by-product of juice production, is a rich source of dietary fiber and bioactive compounds, making it a promising functional ingredient for bakery applications. This study evaluated the physicochemical and sensory properties of shortbread cookies enriched with apple pomace dried under different conditions, while also analyzing the drying process, focusing on drying kinetics and powder characteristics. Pomace dried by either contact drying or freeze-drying was ground and used to replace 20% of wheat flour in the cookie formulation. Drying kinetics were best described by the modified Page model, and freeze-dried pomace showed higher grindability than contact-dried samples. Cookies enriched with pomace exhibited similar overall composition, with differences mainly observed in fiber content (9.82–11.75%). Those containing freeze-dried pomace were lighter, with reduced red and increased yellow tones, and were firmer, requiring approximately 30% higher cutting force. Despite differences in physical properties, enriched cookies were consistently rated higher in overall acceptability than the controls. The results indicate that the drying method and temperature influence the physicochemical properties of apple by-product and the resulting cookies, while having mainly minor effects on sensory acceptance, confirming the potential of apple pomace as a functional ingredient in bakery products. Full article

Background: Passive brain–computer interface (pBCI) systems use a combination of electroencephalography (EEG) and machine learning (ML) to evaluate a user’s cognitive and physiological state, with increasing applications in both clinical and non-clinical scenarios. pBCI systems have been limited by their traditional reliance on sensor technologies that cannot easily be integrated into non-laboratory settings where pBCIs are most needed. Advances in textile-electrode-based EEG show promise in overcoming the operational limitations; however, no study has demonstrated their use in pBCIs. This study presents the first application of fully textile-based EEG for pBCIs in differentiating cognitive states. Methods: Cognitive state comparisons between eyes-open (EO) and eyes-closed (EC) conditions were conducted using publicly available data for both novel textile and traditional dry-electrode EEG. EO vs. EC differences across both EEG sensor technologies were assessed in delta, theta, alpha, and beta EEG power bands, followed by the application of a Support Vector Machine (SVM) classifier. The SVM was applied to each EEG system separately and in a combined setting, where the classifier was trained on dry EEG data and tested on textile EEG data. Results: The textile EEG system accurately captured the characteristic increase in alpha power from EO to EC (p < 0.01), but power values were lower than those of dry EEG across all frequency bands. Classification accuracies for the standalone dry and textile systems were 96% and 92%, respectively. The cross-sensor generalizability assessment resulted in a 91% classification accuracy. Conclusions: This study presents the first use of textile-based EEG for pBCI applications. Our results indicate that textile-based EEG can reliably capture changes in EEG power bands between EO and EC, and that a pBCI system utilizing non-traditional textile electrodes is both accurate and generalizable. Full article

Pile-anchor foundations, serving as one of the anchoring solutions to ensure the safety and stability of floating offshore wind turbines, are primarily subjected to inclined loading induced by anchor chain forces, resulting in significantly different bearing behavior compared to conventional vertically loaded pile foundations. However, experimental research on the inclined pullout performance of anchor piles remains insufficient. To address this gap, this study employs a self-developed servo-controlled loading system to investigate the pullout bearing characteristics of anchor piles in dry and saturated sand, considering factors such as pullout angle and loading point depth. The research results show that from the load–displacement curve of the model pile, it can be found that with the increase in displacement, the load it bears first gradually increases to the peak, then decreases, and then gradually stabilizes. The loading angle has a significant impact on the bearing performance of pile-anchor foundations. As the loading angle increases, the failure mode shows pullout failure. When the loading angle increases from 30° to 60°, the bearing performance of the pile foundation decreases by approximately 63%. When the depth of the loading point increases from 0.22 times the pile length to 0.78 times the pile length, the diagonal anchor tensile bearing capacity of the model pile increases by approximately 45%. When the depth of the loading point is the same, the distribution patterns of bending moment and shear force are basically similar. However, the smaller the loading angle, the larger the value. This is because the horizontal load component plays a dominant role. The compression of the piles above and below the loading point, as well as the bending moment, shear force and axial force under saturated sand conditions, are similar to those in dry sand, but their values are reduced by about 50%. It can be seen that the soil conditions have an influence on the bearing characteristics of pile foundations. Full article

This study focuses on Greece, providing a comprehensive climatological analysis of drought conditions from 1960 to 2022. The Standardized Precipitation Index (SPI) and the Standardized Precipitation Evapotranspiration Index (SPEI) were employed on a 1-month timescale to assess meteorological drying conditions over the study period. The Drought Occurrence Probability (DOP), Total Drought Duration (TDD) and drought severity were analyzed spatially, while temporal trends were examined using rolling time windows and the Mann–Kendall test. The findings reveal regional differences in drought characteristics and indicate more intense drought conditions under the SPEI compared to the SPI, underscoring the increasing role of temperature in drought intensification. Full article