Search Results (46)

The Traveling Salesman Problem (TSP) is a fundamental challenge in combinatorial optimization, with wide-ranging applications in logistics, manufacturing, and network design. In addition to the classical formulation, recent years have witnessed the emergence of complex variants, such as the TSP with Drones (TSP-D), TSP with Time Windows, and Prize-Collecting TSP, that incorporate novel constraints reflecting real-world requirements like last-mile delivery and multimodal logistics. This review presents a comprehensive survey of metaheuristic approaches for solving both the classical TSP and its emerging extensions, with particular emphasis on metaheuristic, hybrid methods, and machine learning-enhanced strategies. Recent algorithmic developments, benchmark datasets, and evaluation metrics are investigated, and critical challenges in addressing drone coordination, synchronization, and uncertainty are identified, as well. Bibliometric analysis is further provided to map research trends and the evolution of the field. By synthesizing foundational techniques and state-of-the-art innovations, this review outlines current progress and proposes future directions for metaheuristic optimization in increasingly dynamic and heterogeneous routing scenarios. Full article

Per- and polyfluoroalkyl substances (PFAS) are synthetics prized for their chemical stability and functionality. Legacy PFAS such as perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) have been phased out due to their persistence and toxicity. This study assessed exposure to both legacy and emerging PFAS in 281 urine samples from 8-year-old children participating in the (Infancia y Medio Ambiente) INMA Asturias birth cohort (northwest Spain), a region with a strong industrial background. Dietary and household information was collected via questionnaires, and urine samples were analysed using ultra-high-performance liquid chromatography (UHPLC) coupled with high-resolution mass spectrometry (HRMS) with full-scan acquisition in independent all-ion fragmentation mode. A suspected screening approach was applied to discover previously unreported PFAS and expand the detectable chemical profile, complemented by targeted analysis of 29 compounds selected for their persistence and regulatory relevance. Among them, 17 compounds were confirmed and quantified. The combined targeted and suspect-screening approach also identified novel PFAS, including fluorotelomer carboxylic acids, demonstrating the value of LC-HRMS for detecting unregulated compounds. Emerging PFAS showed the highest detection frequencies and concentrations: trifluoroacetic acid (TFA) and hexafluoropropylene oxide dimer acid (HFPO-DA, GenX) were detected in 63% and 27% of samples, respectively, with GenX reaching 10.1 ng/mL, whereas PFOA and PFOS were detected less frequently (8.5% and 3.2%) and at concentrations below 1 ng/mL, highlighting the need for epidemiological studies to achieve comprehensive PFAS exposure assessments. Associations with dietary habit exposure estimates point to dairy, protein-rich foods, vegetables, and drinking water as the main contributors. Full article

Camellia reticulata is a valuable woody species prized for both its ornamental and oil-producing qualities. This study focused on four qualitative traits and nine quantitative traits of the fruits collected from nine wild populations and 30 cultivated varieties of C. reticulata. Multivariate statistical methods were employed to analyze the variation patterns of these fruits among populations and varieties, aiming to provide a scientific basis for the resource utilization and genetic improvement of this species. The results showed that the pericarp color clustered into two series: an orange-yellow (red) series (found in eight populations and all 30 cultivars) and a yellow-green series (unique to the Heiniu Mountain I population). The a* value was identified as the key indicator for distinguishing between these two color-series. The fruit shape was predominantly spherical, the seed shape was mostly hemispherical, and the seed coat color was primarily brown. Significant differences (p < 0.05) were observed among the nine quantitative phenotypic traits. Fruit weight exhibited the greatest variation (ranging from 28.499 g to 149.068 g), with particularly prominent differences among populations (Fengqing I was the heaviest at 149.068 g, while Yongping I was the lightest at 28.499 g). The coefficients of variation (CV) for phenotypic traits within populations ranged from 17.209% to 60.803% (mean 31.655%), and within varieties from 13.951% to 72.911% (mean 35.290%). Based on CV weights, seed weight showed the largest variation amplitude (21.342%) among populations, while seed number showed the largest variation amplitude (22.956%) among varieties. Correlation analysis revealed that all nine traits exhibited highly significant correlations across different populations and cultivars. Principal component analysis (PCA) indicated that the eigenvalues of the first two principal components were both greater than 1.00, with cumulative contribution rates reaching 73.570% for populations and 76.064% for cultivars, respectively. Cluster analysis grouped the studied materials into three clusters. The comprehensive evaluation identified the cultivar ‘Lichan’ as having the optimal performance (F = 2.410). Box plots revealed greater dispersion in seed number and pericarp thickness within wild populations, while cultivated varieties showed a wider distribution in locule number and fruit transverse diameter. Frequency distribution analysis demonstrated that all traits followed a normal distribution (R² = 0.673~0.999). Among them, fresh seed weight and fruit transverse diameter displayed obvious skewness. Furthermore, the variation in seed number was significantly higher in wild populations than in cultivars. This study reveals rich phenotypic variation in fruit traits between wild populations and cultivated groups of C. reticulata, with fruit size and seed number identified as key traits. These findings provide an important basis for the subsequent selection of hybrid parents and breeding of high-yield, high-oil varieties. Full article

The Wuding chicken, a renowned indigenous breed in Yunnan Province, is prized for its superior meat quality; however, its economic potential is limited by pronounced broodiness and suboptimal egg production. Central to alleviating these constraints is the precise regulation of ovarian granulosa cell (GC) proliferation and steroidogenic processes that dictate follicular development and laying performance. While Estrogen Receptor 2 (ESR2) is a known transcription factor implicated in follicular maturation, its spatiotemporal dynamics within the hypothalamic-pituitary-ovarian (HPO) axis and its specific regulatory mechanisms in Wuding chicken remain elusive. This study characterizes ESR2 expression across the HPO axis during the laying and broody periods and functionally validates its role in GCs. We observed that ESR2 expression was significantly higher throughout the HPO axis during the laying period compared to the broody period, with the most pronounced differential expression occurring in the ovary. Notably, subcellular localization analysis revealed that ESR2 is distributed in both the nucleus and the cytoplasm, indicating involvement in both nuclear transcriptional regulation and cytoplasmic signaling. Functional assays demonstrated that ESR2 modulates the expression of genes associated with GC proliferation, steroidogenesis, and apoptosis, involving the PI3K/AKT/mTOR signaling pathway. Our findings indicate that this process involves a synergistic interplay between genomic and potential non-genomic actions. Specifically, ESR2 overexpression upregulates the expression of key signaling components and steroidogenic genes, including CYP19A1, STAR, PTGS2, and FSHR, while its cytoplasmic localization suggests a role in non‑genomic interactions. Together, these coordinated mechanisms synergistically maintain GC functional homeostasis. Collectively, these results prove that ESR2 plays an important role in regulating GC homeostasis and follicular development through genomic and non-genomic modes of action. These findings provide a molecular basis for the role of ESR2 in avian follicular development and offer potential targets for improving the reproductive efficiency of Wuding chickens. Full article

Tetrastigma hemsleyanum Diels et Gilg (T. hemsleyanum) is a prized Chinese medicinal plant renowned for its medicinal and economic importance. In our previous study, a key auxin-related gene ThGH3.1 (encoding amide synthetase) was identified by quantitative transcriptome sequencing. To explore ThGH3.1 function in root development, we generated ThGH3.1-overexpressing and RNA interference (RNAi) transgenic hairy root lines via Agrobacterium rhizogenes (A. rhizogenes)-mediated genetic transformation. The results showed that overexpression of ThGH3.1 significantly inhibited the total length and the lateral root number of hairy roots, accompanied by significantly increased levels of methyl indole-3-acetate (MeIAA) and indole-3-acetyl-aspartate (IAA-Asp). In contrast, ThGH3.1 knockdown displayed an opposite trend. To further confirm the function of ThGH3.1, the overexpression vector was heterologously transformed into wild-type Arabidopsis. After single-copy and homozygous line screening, three overexpressing lines (named G19, G29, and G32) were obtained. The primary root length of transgenic Arabidopsis was significantly shortened, with a significant increase in indole-3-acetonitrile (IAN) levels. Further pot experiments revealed that transgenic Arabidopsis grew more slowly, had significantly smaller leaf areas, and lower plant height. The indole-3-acetic acid (IAA) treatment suggested that ThGH3.1 responded to IAA. Collectively, these findings highlight the crucial roles of ThGH3.1 in regulating root development, which will deepen our understanding of the molecular mechanisms underlying root development in T. hemsleyanum. Full article

To characterize the key odorants and elucidate the flavor profiles of compound fermented beverages after fermentation, single-compound fermented beverages (GW, AW) and a compound fermented beverage (CW) were prepared using Italian Riesling grapes and SirPrize apples as raw materials. The flavor and metabolite profiles were systematically analyzed by integrating flavoromics (comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry, GC × GC–TOF MS) and metabolomics (LC–MS/MS). The results demonstrated that CW exhibited the most favorable acid/reducing sugars (2.18), imparting a drier taste and superior stability. Compounds with relative odor activity values (rOAV) greater than 1—including 3-methyl-1-butyl acetate, ethyl hexanoate, ethyl butanoate, and ethyl octanoate—collectively contributed prominent fruity, floral, and sweet aromas to all three wine types. Ethyl decanoate provided an additional distinctive traditional fruity note specifically to AW, while 1-octen-3-ol contributed a mushroom-like aroma to both GW and CW. Moreover, 3-methylbutanal, 4-ethyl-2-methoxyphenol, and ethyl 3-methylbutanoate added additional significant aroma contributions to CW, imparting floral, clove-like, and fruity notes, respectively. Notably, ethyl hexanoate (fruity aroma) exhibited a remarkably high rOAV of 27.43 in CW, significantly surpassing its levels in the single-substrate fermentations. Lipid metabolism and the phenylpropanoid pathway were significantly activated in CW, facilitating the coordinated synthesis of esters and phenolic compounds. Sensory attribute network analysis further confirmed that CW possessed more pronounced “sweet”, “fruity”, and “floral” characteristics. Correlation analysis revealed significant relationships between volatile organic compounds (VOCs) and total soluble solids (TS), titratable acidity (TA), the TA/TS ratio, and metabolite levels, underscoring the close connections among physicochemical properties, precursor/intermediate metabolites, and flavor formation. Comprehensive analysis of non-volatile metabolites and flavor-associated VOCs revealed variety-specific characteristics and compounding effects, providing valuable insights for enhancing the quality of compound fermented beverages. Full article

Rigid polyurethane foams (RPUFs) are essential polymeric materials, prized for their low density, high mechanical strength, and superior thermal insulation, making them indispensable in construction, refrigeration, and transportation. Despite these advantages, their highly porous, carbon-rich structure renders them intrinsically flammable, promoting rapid flame spread, intense heat release, and the generation of toxic smoke. Traditional strategies to reduce flammability have primarily focused on incorporating additive or reactive flame retardants into the foam matrix, which can effectively suppress combustion but often compromise mechanical integrity, suffer from migration or compatibility issues, and involve complex synthesis routes. Despite recent progress, the long-term stability, scalability, and durability of surface flame-retardant coatings for RPUFs remain underexplored, limiting their practical application in industrial environments. Recent advances have emphasized the development of surface-engineered flame-retardant coatings, including intumescent systems, inorganic–organic hybrids, bio-inspired materials, and nanostructured composites. These coatings form protective interfaces that inhibit ignition, restrict heat and mass transfer, promote char formation, and suppress smoke without altering the intrinsic properties of RPUFs. Emerging deposition methods, such as layer-by-layer assembly, spray coating, ultraviolet (UV) curing, and brush application, enable precise control over thickness, uniformity, and adhesion, enhancing durability and multifunctionality. Integrating bio-based and hybrid approaches further offers environmentally friendly and sustainable solutions. Collectively, these developments demonstrate the potential of surface-engineered coatings to achieve high-efficiency flame retardancy while preserving thermal and mechanical performance, providing a pathway for safe, multifunctional, and industrially viable RPUFs. Full article

The Molise region in Central-Southern Italy is a major contributor to national truffle production, particularly of the highly prized Tuber magnatum Picco, accounting for approximately 40% of the country’s total output and hosting the highest density of truffle harvesters. Despite this, research on the Italian white truffle populations from this area remains limited. Therefore, the primary objective of the present study was to address this knowledge gap by characterizing four T. magnatum Picco populations collected from the municipalities of Agnone, Carovilli, Castel del Giudice, and Pietrabbondante, located in “Alto Molise”, through morphological, genetic, and microbiological investigations. The statistical analyses revealed significant differences in peridium thickness and ascocarp-associated microbiota even though pairwise comparisons did not identify statistically significant differences between specific population pairs. No significant variation was observed in ascocarp weight and maturation degree. Furthermore, the presence of a unique haplotype at the single-locus marker SCAR A21-inf was confirmed in a subset of the analyzed fruiting bodies. Collectively, these findings expand current biological knowledge of the Molise white truffle and provide a foundation for future research aimed at identifying specific provenance markers to discriminate truffle populations at both regional and local scales. Full article

Lilac (Syringa spp.) is a widely cultivated ornamental plant prized for its fragrant aroma and attractive flower colors. However, the molecular mechanisms governing its flower pigmentation remain poorly understood. In this study, we performed integrated transcriptomic and metabolomic analyses on purple (Syringa oblata) and white (Syringa oblata var. alba) lilacs at the P1 stage, the point of deepest pigmentation. Compared with W1, P1 has a total of 918 differentially expressed genes, including 614 up-regulated genes and 304 down-regulated genes. And S. oblata exhibited significant upregulation of key anthocyanin biosynthesis genes, including the rate-limiting enzyme gene ObDFR, ObF3’H and transcriptional regulators such as ObWPA, which encodes a WD40 repeat protein. This transcriptional activation was accompanied by a substantial accumulation of 27 anthocyanins, including Petunidin Chloride, Cyanidin Chloride, Delphinidin and so on, while the Petunidin-3-O-rutinoside, Petunidin-3-O-(6-O-p-coumaroyl)-glucoside and Malvidin-3-O-sambubioside-5-O-glucoside were only detected in S. oblata. Furthermore, ATAC-seq analysis revealed that, in comparison to white lilac, purple lilac exhibited 3522 and 805 genes with increased and decreased chromatin accessibility, respectively. Integrative analysis with the transcriptome identified 135 genes that were both more accessible and transcriptionally upregulated in purple lilac, including ObWPA, Ob0214386, and Ob0227194 which belong to WD40 members. Subsequent qRT-PCR validation confirmed ObWPA as the most significantly upregulated gene in purple lilac, a finding consistent with the specific chromatin accessibility detected in its promoter region. To validate its function, we knocked down ObWPA expression in purple lilac using Virus-Induced Gene Silencing (VIGS). This intervention resulted in a dramatic color shift from purple to white, concomitant with a significant decrease in key anthocyanin metabolites such as Cyanidin-3-(6-O-p-caffeoyl)-glucoside, Cyanidin Chloride, Pelargonidin, Cyanidin-3-O-rutinoside, Dihydrokaempferol, and Petunidin Chloride. Collectively, our findings demonstrate that ObWPA is an indispensable positive regulator of purple color formation in S. oblata. Full article

Antimicrobial peptides (AMPs) are crucial components of innate immunity and promising leads for new anti-infective therapies, prized for their broad-spectrum activity and membrane-disruptive mechanisms. However, traditional models of antimicrobial action and resistance often focus on single-cell responses or genetically encoded resistance, overlooking the complex collective behaviors of bacteria at the population level. A growing body of evidence indicates that bacterial communities can profoundly influence AMP efficacy through emergent, community-level resistance mechanisms. In this review, we examine how population-level dynamics and interactions enable bacteria to withstand AMPs beyond what is predicted by cell-autonomous models. We first describe the mechanisms of peptide sequestration by bacterial debris, dead cells, outer membrane vesicles, and biofilm matrix polymers, which diminish the concentration of active peptide available to kill neighboring cells. We then analyze how population-level traits—including inoculum effects, phenotypic heterogeneity, and persister subpopulations—shape survival outcomes and promote regrowth after treatment. Cooperative processes such as protease secretion further enhance communal defenses by coordinating or amplifying protective responses. Beyond cataloging these mechanisms, we highlight recent advances in microfluidic tools, single-cell imaging, and biophysical modeling that reveal the spatial and temporal dynamics of AMP action in structured populations. Collectively, these insights show how bacterial communities absorb, neutralize, or delay AMP activity without genetic resistance, with important implications for therapeutic design and the evaluation of AMP efficacy. Full article

Wireless sensor networks (WSNs) have attracted significant attention due to their widespread applications in various fields such as environmental monitoring, agriculture, intelligent transportation, and healthcare. In these networks, the power cost of a sensor node is closely related to the radius of its coverage area, following a nonlinear relationship where power increases as the coverage radius grows according to an attenuation factor. This means that increasing the coverage radius of a sensor leads to a corresponding increase in its power cost. Consequently, minimizing the total power cost of the network while all clients are served has become a crucial research topic. The power cover problem focuses on adjusting the power levels of sensors to serve all clients while minimizing the total power cost. This survey focuses on the power cover problem and its related variants in WSNs. Specifically, it introduces nonlinear integer programming formulations for the power cover problem and its related variants, all within the specified sensor setting. It also provides a comprehensive overview of the power cover problem and its variants under both specified and unspecified sensor settings, summarizes existing results and approximation algorithms, and outlines potential directions for future research. Full article

Radish (Raphanus sativus), a commonly grown root vegetable prized for its nutrition and culinary use, is particularly vulnerable to lead (Pb) stress, which mainly results in Pb accumulation in the roots. However, the molecular mechanisms underlying Pb accumulation in radish remain largely unknown. In this study, we investigated the role of BASIC PENTACYSTEINE (BPC) genes in radish’s response to Pb stress. Phylogenetic analysis revealed that radish contains 10 BPC genes, which are distinctly clustered in Cluster III. Expression analysis revealed that, except for RsBPC2, RsBPC4, and RsBPC7, the expression of most RsBPC genes was significantly altered under Pb stress. Notably, the expression of RsBPC5 gradually decreased with prolonged Pb exposure. Subcellular localization analysis confirmed that RsBPC5 is localized in the nucleus and acts as a transcriptional repressor. Functional assays demonstrated that transient overexpression of RsBPC5 enhanced the tolerance of radish plants to Pb stress via reducing Pb accumulation and activating the antioxidant defense system. Collectively, our findings suggest that RsBPC5 plays a key role in radish’s response to Pb stress, potentially improving Pb tolerance by modulating Pb uptake and strengthening antioxidant defense mechanisms. Full article

Kazakhstan’s rich biodiversity includes diverse apple populations, notably the wild apple tree (Malus sieversii) prized for traits like disease resistance and adaptability, potentially aiding breeding programs. Analyzing their microbiomes offers insights into bacterial diversity and how it influences apple tree development, making it a reliable method for understanding ecological interactions. In this research, 334 apple tree samples were collected from different mountain ranges in southeastern Kazakhstan. An analysis using nanopore-based 16S rRNA sequencing showed a distinct similarity in the microbiome compositions of samples from the Zhongar and Ile Alatau mountain ranges, with a predominance of Pseudomonadaceae, Enterobacteriaceae, and Microbacteriaceae. In contrast, samples from Ketmen ridge showed a higher prevalence of Enterobacteriaceae. Alongside the less represented Pseudomonadaceae family, in the Ketmen ridge region, bacteria of the Xanthomonadaceae, Alcaligenaceae, and Brucellaceae families were also present. Across all regions, beneficial plant-associated bacteria were identified, such as Pseudomonas veronii, Stenotrophomonas geniculata, and Kocuria rhizophila, potentially enhancing plant resilience. However, opportunistic phytopathogens were also detected, including Pseudomonas viridiflava and Serratia marcescens, particularly in the Ile Alatau region. These findings highlight the complex microbial interactions in M. sieversii, thus offering key insights into host—microbe relationships that can inform apple breeding and ecological preservation efforts. Full article

Garlic (Allium sativum L.) is the second most significant species within the Allium genus worldwide, widely used in cooking and both traditional and modern medicine due to its beneficial biological and therapeutic properties. In Italy, diverse pedo-climatic conditions and historical–cultural fragmentation have led to the development of various garlic landraces, prized for their unique organoleptic qualities and cultural importance. This study aimed to assess the intra-varietal diversity and uniqueness of two red garlic landraces from the Lazio region in central Italy, “Aglio Rosso di Castelliri” and “Aglio Rosso di Proceno”, using SSR and ISSR molecular markers, along with evaluations of bulb morphological traits, total phenolic content, and antioxidant properties. The molecular analysis included 11 accessions of “Aglio Rosso di Castelliri”, nine of “Aglio Rosso di Proceno”, and 15 control accessions, comprising eight Italian red-type garlic landraces, four Spanish red garlic commercial varieties, two white garlic accessions, and an accession of A. ampeloprasum var. holmense used as an outgroup. SSR and ISSR markers revealed moderate genetic diversity within the collection, with mean PIC values of 0.41 and 0.17, respectively. The molecular data identified four distinct genetic clusters, with the two Lazio landraces forming separate groups, indicating their genetic distinctiveness. The results from the STRUCTURE analysis support the hypothesis that these landraces may have originated from the widely cultivated “Aglio Rosso di Sulmona” or a common ancestral population once prevalent in central Italy. The study also revealed significant intra-population genetic diversity within the two garlic landraces, underscoring the need for in situ conservation and clonal selection. Phenotypic evaluations confirmed the distinctiveness of the two landraces, with “Aglio Rosso di Castelliri” characterized by smaller bulbs and cloves with higher dry matter content and distinct color profiles. Additionally, significant variation in total phenolic content and antioxidant activity was observed by analyzing 13 selected accessions from the two landraces (six from “Aglio Rosso di Proceno” and seven from “Aglio Rosso di Castelliri”) and five red garlic control accessions, with the two Lazio landraces exhibiting higher levels than the control group. This study highlights the importance of integrating molecular, phenotypic, and chemical analyses to understand garlic landrace diversity, with significant implications for their conservation and protection of local agro-food products. Full article

Saffron (Crocus sativus L.) is one of the most expensive spices in the world. Saffron, prized for its vibrant color, aroma, and taste, is essential in the food industry and traditional medicine. Its culinary uses, therapeutic benefits, and potential antioxidant, anti-inflammatory, and anticancer properties highlight its significant importance. Its genetic diversity has significant implications for cultivation and quality. In this study, genetic diversity among 76 saffron accessions, collected from 13 localities of Taliouin region of Morocco, were evaluated using sequence-related amplified polymorphism (SRAP) markers. A total of 63 polymorphic fragments were produced with an average of total number and polymorphic bands per primer were of 10.5 and 10.16, respectively. Most of the variations among the localities, revealed by the Analysis of Molecular Variance, originated from the within accessions differentiation (81%; p < 0.010). Cluster Analysis, Principal Coordinate Analysis (PCoA), and population structure confirmed the main groups and corroborated genetic homogeneity across accessions. In fact, close relationships were revealed between accessions from different locations, showing that there was no relationship between genetic divergence and geographical locality. This investigation represents a pivotal advance towards fostering sustainable development and bolstering the economic empowerment of the saffron farming communities in Morocco. Full article