Search Results (12,359)

Background: Raspberry leaf (RL; Rubus idaeus) is a by-product of raspberry cultivation and has been proposed to be a rich source of micronutrients and potential bioactive components, including polyphenols. However, the precise chemical composition of the non-nutrient (poly)phenols in RL has not been as extensively studied. Objective: To evaluate the (poly)phenolic content of six RL samples from different geographical locations and to explore the impact of brewing duration on the levels of phenolic compounds available for absorption following consumption. Methods: A total of 52 polyphenolic constituents were investigated in the RL samples using Liquid Chromatography–Mass Spectrometry (LC-MS), and RL tea samples were analysed for ellagitannins, flavonoids, and phenolic acids. Tea samples were extracted using 80:20 (v/v) methanol/acidified water (0.1% formic acid) to maximise polyphenol recovery, with two sonication steps (30 and 25 min), followed by centrifugation, filtration, and storage at −18 °C. Extractions were performed in triplicate for comprehensive profiling. Additionally, raspberry leaf tea (2 g) was brewed in 200 mL of boiling water at various times (0.5–20 min) to simulate standard consumption practices; this was also performed in triplicate. This approach aimed to quantify polyphenols in the brew and identify optimal steeping times for maximum polyphenol release. Results: Raspberry leaf (RL) samples from six geographical sources were analysed, with 37 compounds identified in methanol and 37 in water out of the 52 targeted compounds, with only 7 compounds not detected in either methanol or water extracts. The analysis indicated that the total measured polyphenol content across the six samples from various sources ranged between 358.66 and 601.65 mg/100 g (p < 0.001). Ellagitannins were identified as the predominant polyphenolic compound in all RL samples, ranging from 155.27 to 394.22 mg/100 g. The phenolic acid and flavonoid concentrations in these samples exhibited a relatively narrow range, with the phenolic acids spanning from 38.87 to 119.03 mg/100 g and the flavonoids ranging from 125.03 to 156.73 mg/100 g. When brewing the tea, the 5 min extraction time was observed to yield the highest level of polyphenols (505.65 mg/100 g) (p< 0.001), which was significantly higher than that with shorter (409.84 mg/100g) and longer extraction times (429.28 mg/100 g). Notably, ellagic acid levels were highest at 5 min (380.29 mg/100 g), while phenolic acid peaked at 15 min (50.96 mg/100 g). The flavonoid content was shown to be highest at 4 min (82.58 mg/100 g). Conclusions: RL contains a relatively high level of polyphenols, particularly ellagic acid; thus, its consumption may contribute to the daily intake of these health-beneficial non-nutrient components. Full article

The environment presently contains greater amounts of heavy metals due to human activities, causing toxicity, mutagenicity, and carcinogenicity. This study evaluated a chitosan (CS) composite material combined with 1,3-dichlorocetone to extract heavy metals from affected waters, integrating experimental and computational analyses. The synthesis of chitosan, obtained from shrimp waste chitin, reached a yield of 85%. FTIR analysis confirmed key functional groups (NH₂ and OH), and XRD showed high crystallinity with peaks at 2θ = 8° and 20°. The physicochemical properties evaluated included a moisture content of 7.3%, ash content of 2.4%, and a deacetylation degree of 73%, consistent with commercial standards. Chitosan exhibited significant solubility in 1.5% acetic acid, moderate solubility in water, and insolubility in NaOH, demonstrating its versatility for environmental applications. In adsorption tests, heavy metal concentrations were reduced by CS derivatives, with Cr and Pb dropping to 0.03 mg/L, and Cu and Zn to less than 0.05 mg/L. CS cross-linked with 1,3-dichlorocetone proved the most efficient, outperforming other derivatives such as glutaraldehyde and epichlorohydrin. Computational analysis evaluated key molecular interactions using DFT and the B3LYP/LANLD2Z method. The band gap energies (HOMO–LUMO) decreased to 0.09753 eV for Zn and 0.01485 eV for Pb, indicating high affinity, while Cd showed lower interaction (0.11076 eV). The total dipole moment increased remarkably for Zn (14.693 Debye) and Pb (7.449 Debye), in contrast to Cd (4.515 Debye). Other descriptors, such as chemical hardness (η), reflected a higher reactivity for Zn (0.04877 eV) and Pb (0.00743 eV), which favors adsorption. The correlation between experimental and computational results validates the efficiency and selectivity of CS/1,3-dichlorocetone for removing heavy metals, especially Pb and Zn. This material stands out for its adsorbent capacity, sustainability, and economic viability, positioning it as a promising solution for wastewater remediation. Full article

Coastal erosion is a critical environmental challenge in the Upper Gulf of Thailand, driven by both natural processes and human activities. This study analyzes 35 years (1988–2023) of shoreline changes using geoinformatics, machine learning algorithms (Random Forest, Support Vector Machine, Maximum Likelihood, Minimum Distance), and the Digital Shoreline Analysis System (DSAS). The results show that the Random Forest algorithm, utilizing spectral bands and indices (NDVI, NDWI, MNDWI, SAVI), achieved the highest classification accuracy (98.17%) and a Kappa coefficient of 0.9432, enabling reliable delineation of land and water boundaries. The extracted annual shorelines were validated with high accuracy, yielding RMSE values of 13.59 m (2018) and 8.90 m (2023). The DSAS analysis identified significant spatial and temporal variations in shoreline erosion and accretion. Between 1988 and 2006, the most intense erosion occurred in regions 4 and 5, influenced by sea-level rise, strong monsoonal currents, and human activities. However, from 2006 to 2018, erosion rates declined significantly, attributed to coastal protection structures and mangrove restoration. The period 2018–2023 exhibited a combination of erosion and accretion, reflecting dynamic sediment transport processes and the impact of coastal management measures. Over time, erosion rates declined due to the implementation of protective structures (e.g., bamboo fences, rock revetments) and the natural expansion of mangrove forests. However, localized erosion remains persistent in low-lying, vulnerable areas, exacerbated by tidal forces, rising sea levels, and seasonal monsoons. Anthropogenic activities, including urban development, mangrove deforestation, and aquaculture expansion, continue to destabilize shorelines. The findings underscore the importance of sustainable coastal management strategies, such as mangrove restoration, soft engineering coastal protection, and integrated land-use planning. This study demonstrates the effectiveness of combining machine learning and geoinformatics for shoreline monitoring and provides valuable insights for coastal erosion mitigation and enhancing coastal resilience in the Upper Gulf of Thailand. Full article

Research on the multi-field coupling effects in rocks has been ongoing for several decades, encompassing studies on single physical fields as well as two-field (TH, TM, HM) and three-field (THM) couplings. However, the environmental conditions of rock masses in deep resource extraction and underground space development are highly complex. In such settings, rocks are put through thermal-hydrological-mechanical-chemical (THMC) coupling effects under peak temperatures, strong osmotic pressures, extreme stress, and chemically reactive environments. The interaction between these fields is not a simple additive process but rather a dynamic interplay where each field influences the others. This paper provides a comprehensive analysis of fragmentation evolution, deformation mechanics, mechanical constitutive models, and the construction of coupling models under multi-field interactions. Based on rock strength theory, the constitutive models for both multi-field coupling and creep behavior in rocks are developed. The research focus on multi-field coupling varies across industries, reflecting the diverse needs of sectors such as mineral resource extraction, oil and gas production, geothermal energy, water conservancy, hydropower engineering, permafrost engineering, subsurface construction, nuclear waste disposal, and deep energy storage. The coupling of intense stress, fluid flow, temperature, and chemical factors not only triggers interactions between these fields but also alters the physical and mechanical properties of the rocks themselves. Investigating the mechanical behavior of rocks under these conditions is essential for averting accidents and assuring the soundness of engineering projects. Eventually, we discuss vital challenges and future directions in multi-field coupling research, providing valuable insights for engineering applications and addressing allied issues. Full article

Automatic glacier extraction from remote sensing images is the most important approach for large scale glacier monitoring. Commonly used band calculation indices to enhance glacier information are not effective in identifying shadowed glaciers and debris-covered glaciers. In this study, we used the Kolmogorov–Smirnov test as the theoretical basis and determined the most suitable band calculation indices to distinguish different land cover classes by comparing inter-sample separability and reasonable threshold range ratios of different indices. We then constructed a glacier classification decision tree. This approach resulted in the development of a method to automatically extract glacier areas at given spatial and temporal scales. In comparison with the commonly used indices, this method demonstrates an improvement in Cohen’s kappa coefficient by more than 3.8%. Notably, the accuracy for shadowed glaciers and debris-covered glaciers, which are prone to misclassification, is substantially enhanced by 108.0% and 6.3%, respectively. By testing the method in the Qilian Mountains, the positive prediction value of glacier extraction was calculated to be 91.8%, the true positive rate was 94.0%, and Cohen’s kappa coefficient was 0.924, making it well suited for glacier extraction. This method can be used for monitoring glacier changes in global mountainous regions, and provide support for climate change research, water resource management, and disaster early warning systems. Full article

In recent years, the bioactive compounds extracted from Sanghuangporus, especially polysaccharides, phenols, and triterpenoids, have attracted great interest from people due to their extensive biological activity. Among them, polysaccharides are mainly extracted from the seed bodies, mycelium, and fermentation broth of Sanghuangyuan, exhibiting notable effects including immunomodulation, antitumor properties, and hypoglycemic effects. This article provides a comprehensive review of the extraction process, structural characteristics, and antitumor mechanism of Sanghuangyuan polysaccharides. First, the different extraction methods, such as hot water extraction, enzyme-assisted extraction, and ultrasonic-assisted extraction, are summarized. Then, the structure of the Sanghuangporus polysaccharide is studied in detail. Moreover, the antitumor mechanisms demonstrate significant inhibitory impacts on various malignant tumors, spanning gastric, hepatic, colorectal, breast, and prostate cancers. This groundbreaking revelation is of great significance for both the food and pharmaceutical sectors, presenting innovative pathways for Sanghuangyuan utilization and potentially inducing advancements in product development, treatment modalities, and therapeutic interventions. Full article

Garcinia lanceifolia Roxb. (Rupohi thekera), an underutilized minor fruit from Assam, holds significant potential as it exhibits substantial traditional medicinal properties. However, its preservation and utilization remain limited, necessitating effective processing techniques. This study aimed to compare the impact of tray drying and freeze drying on the physico-chemical, antioxidant, and functional properties of G. lanceifolia. Fresh fruits were processed using both methods, followed by detailed analyses of nutritional composition, phytochemical content, antioxidant activity, and functional properties. Freeze drying resulted in greater retention of moisture (12.42 ± 0.81%), protein (4.44 ± 0.19%), carbohydrate content (8.29 ± 0.31 g/100 g), and reducing sugar (1.95 ± 0.12%), along with prominent color quality, while no significant difference in ash content was found for either drying method employed. Phytochemical extraction using different solvents (water, n-hexane, 80% methanol, 80% ethanol, and 80% acetone) revealed that freeze-dried samples extracted with acetone had the highest total phenolic content (634.00 ± 1.73 mg GAE/100 g), while methanol extraction yielded the highest total flavonoid content (382.33 ± 1.52 mg QE/100 g). Tray drying, on the other hand, exhibited superior DPPH and FRAP when subjected to ethanol extract (80.24 ± 0.42% and 83.83 ± 0.46 mg/100 g, respectively) and metal chelation capacity (23.69 ± 2.09%). Additionally, functional properties, such as glucose adsorption capacity and α-amylase inhibition, were found to vary between drying techniques, with freeze-dried samples showing better glucose adsorption and tray-dried samples demonstrating greater α-amylase inhibition. FTIR analysis highlighted distinct structural attributes of bioactive compounds retained through both methods. The findings underscore the potential of freeze drying for nutrient preservation and tray drying for cost-effective applications, paving the way for the industrial valorization of G. lanceifolia as a functional food ingredient. Full article

Icebergs pose significant risks to shipping, offshore oil exploration, and underwater pipelines. Detecting and monitoring icebergs in the North Atlantic Ocean, where darkness and cloud cover are frequent, is particularly challenging. Synthetic aperture radar (SAR) serves as a powerful tool to overcome these difficulties. In this paper, we propose a method for automatically detecting and classifying icebergs in various sea conditions using C-band dual-polarimetric images from the RADARSAT Constellation Mission (RCM) collected throughout 2022 and 2023 across different seasons from the east coast of Canada. This method classifies SAR imagery into four distinct classes: open water (OW), which represents areas of water free of icebergs; open water with target (OWT), where icebergs are present within open water; sea ice (SI), consisting of ice-covered regions without any icebergs; and sea ice with target (SIT), where icebergs are embedded within sea ice. Our approach integrates statistical features capturing subtle patterns in RCM imagery with high-dimensional features extracted using a pre-trained Vision Transformer (ViT), further augmented by climate parameters. These features are classified using XGBoost to achieve precise differentiation between these classes. The proposed method achieves a low false positive rate of 1% for each class and a missed detection rate ranging from 0.02% for OWT to 0.04% for SI and SIT, along with an overall accuracy of 96.5% and an area under curve (AUC) value close to 1. Additionally, when the classes were merged for target detection (combining SI with OW and SIT with OWT), the model demonstrated an even higher accuracy of 98.9%. These results highlight the robustness and reliability of our method for large-scale iceberg detection along the east coast of Canada. Full article

Insect metabolites are known for their preservative potential, but the time-consuming and unsustainable extraction process compromises their transferability. This study aimed to identify user-friendly solutions based on the use of insect meals that could improve microbiological safety as well as consumer acceptability. In this regard, the antimicrobial activity of Alphitobius diaperinus and Tenebrio molitor meals against surrogate strains of Gram-positive (Listeria monocytogenes) and Gram-negative (Escherichia coli) pathogenic bacteria and mycotoxin-producing fungi (Penicillium expansum) was evaluated. Minimum inhibitory concentration values of between 3.12 mg/mL vs. Listeria innocua and 12.50 mg/mL vs. Escherichia coli were found. Based on this finding, a model food was developed also considering consumer acceptance. Statistical analysis of food preferences showed that nutritional and sustainability claims were the independent variables of greatest interest. Therefore, waste or by-products from other food chains were selected as co-ingredients for sustainability, nutritional, and sensory claims. Analysis of the chemical composition showed that the insect bar-style snack qualifies as a “high-protein” food, as protein provides more than 20% of the energy value. Based on the moisture (30%) and water activity (0.77) values, the bar could be classified as an intermediate-moisture food. The challenge test showed that the insect meal prevented the proliferation of intentionally added undesirable microorganisms. Conclusively, the findings complement the knowledge on the antimicrobial activities of insect meals, offering new possibilities for their use as natural preservative ingredients with nutritionally relevant properties. Full article

Following the successful utilization of various 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ionic liquids (ILs) as effective solvents in the extraction of ethanol, 1-propanol, and 2-propanol from water, we conducted experiments to determine the liquid–liquid equilibria data for the ternary mixture comprising water, ethanol, and 1-decyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([dmim][Tf2N]) at temperatures of 283.2 K, 303.2 K, and 323.2 K under atmospheric pressure. The thermodynamic parameters for both ternary mixtures were calculated using the non-random two-liquid (NRTL) and universal quasichemical (UNIQUAC) models, yielding favorable results across all investigated conditions (rmsd < 0.65%). Subsequently, we explored the efficiency of [dmim][Tf2N] in separating azeotropic mixtures by analyzing the distribution coefficient and selectivity (K₂ and S greater than 1 in all cases, with maximum values of 3.551 and 10.878, respectively). Comparative assessments were made against the performance of various 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ILs and alcohols. The findings underscore the promising capabilities of [dmim][Tf2N] in achieving effective separation, providing valuable insights for potential applications in liquid–liquid extraction processes. Full article

Landscape visual evaluation is a key method for assessing the value of visual landscape resources. This study aims to enhance the visual environment and sensory quality of urban landscapes by establishing standards for the visual comfort of urban natural landscapes. Using line-of-sight and multi-factor analysis algorithms, the method assesses spatial visibility and visual exposure of building clusters in the core urban areas of Harbin, identifying areas and viewpoints with high visual potential. Focusing on the viewpoints of landmark 3D models and the surrounding landscape’s visual environment, the study uses the city’s sky, greenery, and water features as key visual elements for evaluating the comfort of urban natural landscapes. By integrating GIS data, big data street-view photos, and image semantic recognition, spatial analysis algorithms extract both objective and subjective visual values at observation points, followed by mathematical modeling and quantitative analysis. The study explores the coupling relationship between objective physical visual values and subjective perceived visibility. The results show that 3D visual analysis effectively reveals the relationship between landmark buildings and surrounding landscapes, providing scientific support for urban planning and contributing to the development of a more distinctive and attractive urban space. Full article

In the present study, a whey protein-based hydrogel was developed as an alternative for the microencapsulation of Hibiscus extracts. The resulting hydrogels showed a high percentage of moisture and water activity, along with a partial degradation of anthocyanins during their production and storage. The hydrogels exhibited particle sizes between 8 and 15 μm and retained some of the characteristic color properties of extracts. The results obtained provide a novel alternative for the microencapsulation of bioactive compounds through the use of protein-based carrier systems, highlighting their potential for the development of innovative encapsulation systems. Full article

How to quickly and accurately obtain the basal crop coefficient is the key to estimating evapotranspiration in sparse vegetation. To enhance the accuracy of vineyard evapotranspiration estimation in the subhumid region of Northwest China, this study utilized the actual evapotranspiration (ET_c) measured by the Bowen ratio system as the reference standard. The reference crop evapotranspiration (ET_o) was calculated using the Penman formula, and the grape crop coefficient (K_c) was subsequently derived. The FAO-56 dual crop coefficient method was then employed to determine the soil evaporation coefficient (K_e) and the water stress coefficient (K_s), leading to the acquisition of the basal crop coefficient (K_cb). Concurrently, multispectral remote sensing images captured by unmanned aerial vehicle (UAV) were used to gather grape spectral data, from which the reflectance of multiple bands was extracted to compute four vegetation indices: the Normalized Difference Vegetation Index (NDVI), the Soil-Adjusted Vegetation Index (SAVI), the Ratio Vegetation Index (RVI), and the Difference Vegetation Index (DVI). Relationship models between the grape basal crop coefficient (K_cb) and these vegetation indices were established using univariate linear regression, polynomial regression, and multiple linear regression. These models were then used to estimate vineyard evapotranspiration and validate the accuracy of the UAV multispectral remote sensing in estimating the grape K_cb. The results indicated that: (1) The growth stage, type of vegetation index, and modeling method were three significant factors influencing the fitting accuracies of the relationship models between the grape basal crop coefficient (K_cb) and vegetation indices. These model fitting accuracies had a notable impact on the estimation accuracies of evapotranspiration. (2) The application of UAV-based multispectral remote sensing to estimate the grape basal crop coefficient in the subhumid region of Northwest China was feasible. Compared to the K_cb values recommended by the FAO-56, the K_cb values derived from the UAV data improved the estimation accuracies of evapotranspiration by more than 11% in 2021 and 13% in 2022. Full article

This study explores the chemical composition of different macrophyte species and infers their potential in extracting nutrients and some heavy metals from water as well as the use of macrophytes’ biomass as natural fertilizers. It used a dataset obtained from a previous study composed of 445 samples of chemical concentrations in the dried biomass of 16 macrophyte species collected from the Santana Reservoir in Rio de Janeiro, Brazil. Correlation tests, analysis of variance, and factor analysis of mixed data were performed to infer correspondences between the macrophyte species. The results showed that the macrophyte species can be grouped into three different clusters with significantly different profiles of chemical element concentrations (N, P, K⁺, Ca²⁺, Mg²⁺, S, B, Cu²⁺, Fe²⁺, Mn²⁺, Zn²⁺, Cr³⁺, Cd²⁺, Ni²⁺, Pb²⁺) in their biomass (factorial map from PCA). Most marginal macrophytes have a lower concentration of chemical elements (ANOVA p-value < 0.05). Submerged and floating macrophyte species presented a higher concentration of metallic and non-metallic chemical elements in their biomass (ANOVA p-value < 0.05), revealing their potential in phytoremediation and the removal of toxic compounds (such as heavy metal molecules) from water. A cluster of macrophyte species also exhibited high concentrations of macronutrients and micronutrients (ANOVA p-value < 0.05), indicating their potential for use as soil fertilizers. These results reveal that the plant’s location in the reservoir (marginal, floating, or submerged) is a relevant feature associated with macrophytes’ ability to remove chemical components from the water. The obtained results can contribute to planning the management of macrophyte species in large water reservoirs. Full article

Anthocyanins (ANTHs) are polyphenolic compounds with health promoting properties, being known for their strong antioxidant effects as well as for their antimicrobial properties, obesity and cardiovascular disease prevention, and anticarcinogenic activity. Being main dietary components, it is important to know the content of anthocyanins in various dietary sources and their stability in time. The total anthocyanin content (TAC) of various fresh fruits has been spectrophotometrically determined using the pH differential method. The results showed that in the analyzed samples, the TAC increased in the order: blackcurrants > blackberries > blueberries > raspberries > strawberries > plums. The degradation degree of anthocyanins extracted from blueberries (BBEs) in an ethanol/water solution in four experimental conditions was studied. Kinetic studies have been approached, fitting the experimental data recorded by UV–Vis spectrophotometric analysis in agreement with some kinetic models verified for the ANTH degradation reaction. Therefore, zero-order kinetics for BBE extract degradation exposed to sunlight were identified, while for the other storage conditions (shadow, dark, cold), the first-order kinetics were respected. The results indicate that the stability decreased as follows: (ANTH stability)_{sunlight test} << (ANTH stability)_{shadow test} ≈ (ANTH stability)_{dark test} < (ANTH stability)_{cold test}. A mechanism for BBE anthocyanin degradation was proposed and the impact on human health of the degradation products is discussed. Full article