The Science of Nature最新文献

Due to the growing environmental and health concerns with chemical plant stimulants, there is a growing need to find alternative sources of plant stimulants that could help the seeds germinate and sustain their growth in the global climate change scenario. The article compares various seed stimulants such as chemical compounds (benzothiadiazole, salicylic acid, glycine betaine), alcoholic extracts from commercial plant products (English oak bark, ginger spices, turmeric spices, caraway fruits) and from wild plant leaves (Japanese pagoda tree, Himalayan balsam, stinging nettle and Bohemian knotweed) and their effects on wheat seed germination and seedling characteristics. It was found that BTH had significantly lower effect on seedling characteristics such as SG3 (%), SG5 (%), R/S III, SVI I (mm) and SVI III (mg) followed by ZO on SG3 (%), SG5 (%) and GI (unit). Significantly highest R/S III was found in SJ treatment, while SVI I (mm) and SVI III (mg) characteristics were significantly enhanced by treatment with CC and RB. It seems that such plant materials could be useful in alternative agriculture for different purposes.

Fire is a key natural disturbance influencing physical, chemical, and biological processes in the Cerrado. Ash, a fire byproduct, may significantly influence soil macrofauna through its chemical properties. Dung beetles (Scarabaeinae), critical components of Cerrado soil macrofauna, provide key ecological functions and services. Here, we investigate whether ash deposition from burned Cerrado grassland vegetation alters odour-guided foraging in Dichotomius bos, a native dung beetle species, by modifying the composition of volatile organic compounds (VOCs) in faecal resources. We hypothesised that ash would reduce VOC emissions from faeces, thereby decreasing their attractiveness to D. bos. Volatiles from swine faeces, with and without ash, were collected via solid-phase microextraction (SPME) and analysed using gas chromatography-mass spectrometry (GC–MS). Eight VOCs were selected based on their relative abundance and identification: dimethyl trisulfide (DMTS), p-cresol, 3-ethylphenol, 2-undecanone, 2-methylindole, skatole, (Z)-6-pentadecen-1-ol, and heptadecan-1-ol. The relative abundance of all target compounds was reduced in ash-exposed faeces. In four-choice olfactometer trials, D. bos exhibited a strong attraction to swine faecal odours. However, despite reduced VOC relative abundance in ash-treated faeces, beetles showed equivalent attraction to odours from faeces with and without ash. These results suggest D. bos is resilient to post-fire chemical changes in resource odours, likely reflecting adaptations to fire-prone Cerrado ecosystems. Investigating dung beetle responses to fire-derived alterations in resource chemistry may inform management strategies to conserve Cerrado biodiversity under fire regimes.

Wounds with extensive tissue damage are highly susceptible for microbial infections delaying the process of wound healing. Currently, biomaterials with therapeutic molecules emerged as key players in wound repairing. This work developed a novel collagen-based hydrogel loaded with allicin and silver nanoparticles. The allicin is extracted from Allium sativum. The hydrogel demonstrated wound healing efficacy by achieving full closure within 72 h in an in vitro scratch wound assay on Vero cells. The antimicrobial activity of the hydrogel was confirmed against Gram-positive bacteria with zone of inhibition values of 14 mm for Staphylococcus aureus at a concentration of 1000 μg/ml. Cytotoxicity studies on Vero cells, reported significantly low cytotoxicity with 98.11% at a concentration of 7.8 μg/ml indicating its biocompatibility. Zeta potential measurement revealed good stability of the silver nanoparticles with a value of − 27.8 mV. The swelling degree of the hydrogel reached up to 6.11 indicating its capacity to maintain moisture while wound repairing. Altogether, these findings suggests that this biomaterial may represent a promising replacement to wound repairing treatments. Future research focusing in vivo studies could lay a pathway for clinical applications in regenerative medicine.

Insect silk is a naturally occurring protein that forms semicrystalline threads when exposed to air. The Asian weaver ant, Oecophylla smaragdina (Formicidae: Hymenoptera), frequently uses silks for leaf weaving in nest construction to maintain its integrity and durability. The silk imparts resilience and durability to the nests, preventing fracturing or breaking during many natural disasters, particularly heavy rainfall and strong winds. Therefore, understanding the strength and stability of these silk threads necessitates an examination of their structural components and physicochemical properties. Silk samples aged 30 days, 180 days, and 365 days are analysed to assess the temporal differences in silk durability and hardness. According to infrared Fourier transform studies, the silk mostly consists of alkanes, alkenes, amides, and alcohols, while energy-dispersive X-ray analysis identifies carbon, nitrogen, and oxygen as the principal elements, with minor quantities of magnesium, aluminium, silicon, and potassium. As per X-ray powder diffraction, the silk exhibits a crystalline sheet structure. Its mass, thickness, density, and tensile strength increase as the silk becomes older. The ‘contact angle’ of the silk also increases with age, indicating its hydrophobic nature. The thermogravimetric curve shows the fibre’s long-term endurance and thermal stability. The physicochemical properties of Oecophylla silk highlight its unique strength and endurance, explaining why they utilise its advantages to protect their nests from severe environmental conditions.

Amphibians, as a group greatly disturbed by human activities, are at increased risk of extinction. Rana dybowskii is an anuran species with both ecological and economic significance. Due to environmental changes and human overexploitation, it has been classified as Near-Threatened. This study integrates morphological and molecular immunological approaches to identify R. dybowskii populations with greater survival and disease resistance, based on 32 morphological traits and MHC class I and II polymorphism. Morphological results showed that compared with other populations, Yichun (YC) population had the highest fatness, the lowest IOD/HW, and the largest HW/SVL, HL/SVL, HW/HL, SL/TL. It indicates that YC population shows larger body size, wider vision and stronger jumping ability. The polymorphism of MHC I gene was the highest in Shangzhi (SZ) population, and the polymorphism of MHC II gene was the highest in YC population. Moreover, duplication, selection, and recombination occurred during evolution of MHC class I and II genes. Since both SZ and YC populations scored higher in this category (the variant sites, nucleotide polymorphism, amino-acid divergence/nucleotide divergence, dN/dS, Tajima’ D, etc.), they were more resistant to disease. All in all, these results indicated that YC population of the Lesser Khingan Mountains had good morphology and immune results, and R. dybowskii in the Lesser Khingan Mountains might be more suitable to be the original population of artificial breeding, which provided a theoretical basis for the realization of artificial breeding in the next step.

Acute respiratory distress syndrome (ARDS) is a life-threatening complication of COVID-19, often resulting in respiratory failure and high mortality. Identifying effective molecular biomarkers is crucial for understanding its pathogenesis and improving diagnosis and treatment strategies. We analyzed transcriptomic and single-cell RNA-seq data from public datasets (GSE172114, GSE149878, and GSE213313). Differentially expressed genes (DEGs) were identified using the limma package and weighted gene co-expression network analysis (WGCNA). Single-cell analysis was used to define cell-type–specific expression. Three machine learning algorithms—LASSO, SVM-RFE, and Random Forest—were applied to identify robust hub genes. External dataset GSE213313 was used for validation. CIBERSORT was applied to estimate immune cell infiltration in ARDS tissues. We identified 915 DEGs between COVID-19-induced ARDS and controls, mainly enriched in immune receptor activity and cytokine signaling. Through integrative machine learning and validation, SERPINB1 and CPEB4 were identified as key genes, with strong diagnostic performance (AUCs: 0.940 and 0.948, respectively). Immune infiltration analysis revealed that both genes were highly correlated with neutrophils, and also associated with B memory cells, T cells, NK cells, monocytes, and mast cells. GSEA showed these genes were involved in immune and inflammatory pathways, indicating functional relevance in ARDS. SERPINB1 and CPEB4 were identified as novel immune-related biomarkers for COVID-19-induced ARDS. Their strong association with neutrophil infiltration suggests that they may play critical roles in disease progression. These findings provide new insights into immune mechanisms and offer promising targets for early diagnosis and therapeutic intervention in ARDS.

Desertification poses a major ecological threat, demanding insights into plant adaptive strategies for survival in arid landscapes. Tribulus species, i.e., T. longipetalus, T. terrestris, and T. pentandrus, are drought-tolerant herbs commonly distributed across arid and semi-arid regions. Samples from natural populations were collected from diverse ecological zones of the Cholistan Desert exhibiting varying levels of drought intensity and resource availability. In the present study, structural and functional modifications in three Tribulus species under desert stress conditions were evaluated. It was hypothesized that each species would exhibit species-specific morphological, physiological, and anatomical adjustments to optimize survival under desert stress. All three species responded distinctly under different environmental conditions. The most notable feature in T. longipetalus under drier habitats was enhanced accumulation of total soluble proteins, sugars, amino acids, and thicker dermal and vascular tissues supporting stress endurance. T. terrestris exhibited better performance in highly stressful zones, showing increased shoot biomass, soluble osmolytes, and maximum chlorophyll content. T. pentandrus showed vigorous growth in less stressful habitats with highest pigment content and shoot biomass, whereas populations from dry sites displayed increased metaxylem and vascular bundle size. Structural and functional traits such as well-developed vascular bundles, Kranz-type leaf anatomy with thickened mesophyll and bundle sheath cells, and increased epidermal and sclerenchymatous tissues contributed to water retention, transport efficiency, and mechanical support. Significant variability in stomatal traits among species reflected adaptive strategies for gas exchange and water conservation. It was concluded that Tribulus species developed specific anatomical and physiological strategies crucial for ecological fitness, resource use efficiency, and survival under desert stress conditions. These adaptive features enhance their potential for desert reclamation and ecological restoration.

Graphical Abstract

The hylid tribe Sphaenorhynchini includes 15 small, greenish treefrog species within the genera Sphaenorhynchus and Gabohyla. Sphaenorhynchus is divided into three species groups: S. lacteus, S. planicola, and S. platycephalus, with S. carneus and S. prasinus remaining unassigned to any group; Gabohyla is monotypic. Larvae of most species have been described, except for S. botocudo, S. cammaeus, and S. mirim. Although larval morphology holds phylogenetic and diagnostic importance in Sphaenorhynchini, internal morphology remains largely unknown, with only the presence of a lingual papilla noted in S. dorisae and S. lacteus. To fill this gap, we describe the buccopharyngeal cavity of G. pauloalvini, S. prasinus, S. dorisae, S. lacteus, S. canga, and S. palustris. We provide a detailed description of this system for the tribe and discuss putative new larval synapomorphies. Tadpoles of Sphaenorhynchini show similarities in buccopharyngeal cavity morphology but vary in features such as prenarial arena shape, lateral ridge papillae, median ridge, and postnarial crest development. Gabohyla pauloalvini shows reduced lateral ridge papillae, which is an autapomorphy. Lateral roof papillae and a second pair of lateral ridge papillae are putative synapomorphies of the S. platycephalus group or one of its internal clades. The postnarial crest, present in all species, may be a synapomorphy of Sphaenorhynchini. These results enhance understanding of larval morphology and its systematic relevance within the tribe.

Plant galls are newly formed structures that develop due to the influence of gall-inducing organisms, providing them with shelter, protection, and nourishment. The most commonly studied galls are caused by insects. Plant-parasitic nematodes (PPNs) induce gall formation in various parts of plants, primarily targeting the roots. Reports on their effects on aerial parts, especially flowers, are rare. In this study, floral galls induced by Ditylenchus sp. (Anguinidae) in Bongardia chrysogonum (L.) Spach (Berberidaceae) were introduced for first time. The structural traits of galls were analyzed using microscopic studies. The levels of total phenolic compounds and anthocyanins were measured by spectrophotometric methods. Intact flowers had thin sepals and petals with 3–5 cell layers, tetrasporangiate anthers, and a thin pleated gynoecium, while the galled floral parts lacked morphological and anatomical similarity to the intact organs. These galling organisms triggered the regeneration and reorganization of floral parts, leading to abnormal and swollen growths. The number of modified floral whorls in produced gall ranged from 1 to 3, indicating that nematode infection affected some or all floral organs. Microscopic sections of all galls showed homogeneous parenchyma with large intercellular spaces, lacking a gall chamber, and containing numerous nematodes within the tissue. Galled flowers showed red–purple coloration and higher phenolic compound concentrations than normal flowers, as revealed by cytochemical and biochemical analyses. The reorganization of floral parts and the large intercellular spaces can be used for nematode survival and dispersal. High levels of phenolic compounds suggested host plant defense against the nematode.

Soil warming increases carbon emissions by enhancing soil microbial activity. However, only few soil warming experiments have been conducted in the Asian monsoon region (warmer temperate regions with very high precipitation) compared with those conducted in Europe and North America. Hence, in this study, we conducted a soil warming experiment using electric heating cables and solar-powered energy systems in a natural forest in central Japan (Asian monsoon region) to determine the effects of moderate soil warming (1.2 °C increase) on soil properties and microbial decomposition capacity. EcoPlate analysis was used to assess the multifunctionality (MF) of soil microbial decomposition capacity across 31 carbon substrates. MF was significantly higher in the warming plots than in the control plots. When each carbon substrate group was evaluated separately, the MF of labile substrates, such as carboxylic acids, carbohydrates, and amino acids, were significantly higher in the warming plots than in the control plots. Thus, the ordination plot, which was created by performing db-RDA (Distance-based redundancy analysis, constrained ordination of the principal coordinate analysis (PCoA)) with Bray–Curtis dissimilarity, showed differences in the microbial functional composition between the warming and control plots. Moderate soil warming did not cause soil drying; however, it significantly increased soil moisture. Our experimental results demonstrated that moderate soil warming enhanced carbon substrate decomposition by microorganisms and increased soil moisture during the initial decomposition stage in the Asian monsoon region.