Search Results (4,817)

Amphibious assault vehicles serve as core equipment for coastal defense and amphibious operations worldwide, with irreplaceable strategic value. Featuring outstanding comprehensive performance, modern amphibious assault vehicles can maintain stable navigation under Sea States 3–4 and adapt to complex nearshore hydrological environments, emerging as the primary platform for mechanized landing operations of the Marine Corps. Cluster navigation is an inevitable tactical form in the operational application of amphibious assault vehicles. When multiple vehicles sail in formation, the wave-making and water pressure effects induced by individual vehicles generate prominent wave interference drag within the formation, which significantly impacts the overall navigation efficiency and stability. Based on the nearshore combat background of amphibious landing, this paper investigates different formation layouts of amphibious assault vehicle clusters to determine the optimal configuration for group navigation. First, a numerical simulation and a physical experiment are combined; a certain type of amphibious assault vehicle is taken as the prototype for 3D geometric modeling via SOLIDWORKS. Then, adopting the CFD numerical simulation method, with navigation speed and optimal inter-vehicle spacing fixed, variables including formation layout and number of vehicles are controlled to simulate the flow field characteristics and total resistance of different cluster formations in calm water. Meanwhile, 3D printing technology is applied to manufacture scaled-down models for towing tank tests. The experimental results are in good agreement with numerical simulations, revealing the fundamental hydrodynamic laws of formation navigation. Under optimal inter-vehicle spacing, the longitudinal tandem formation achieves the best drag-reduction effect, while the double-column staggered formation (diamond/V formation) can effectively suppress wave interference drag and improve the overall hydrodynamic performance and tactical coordination. The research provides a solid theoretical basis and data support for optimizing formation sailing strategies, enhancing cluster navigation stability and safety, and improving maritime maneuver efficiency. It is also of universal reference value for the tactical deployment of amphibious combat equipment globally. Full article

Purple celery (Apium graveolens L.) is a high-value functional vegetable rich in anthocyanins, but achieving a balanced optimization between biomass accumulation and nutritional quality in plant factories remains challenging due to species-specific spectral trade-offs, and current research lacks integrated light recipes that simultaneously optimize photosynthetic efficiency, antioxidant defenses, and functional quality while suppressing nitrate accumulation. This study evaluated five LED treatments over 30 days: white light (CK), monochromatic red (R), and red-to-blue photon flux density ratios of 5:5, 7:3, and 8:2. Red light induced stem elongation but suppressed root development. Conversely, 8R2B delivered the best performance, significantly elevating leaf, petiole, root, and total fresh biomass and increasing total dry weight by 68.8% over CK. It also markedly enhanced chlorophyll a, b, total chlorophyll, and carotenoids, as well as improved PSII quantum yield (YII), photochemical quenching (qP), and electron transport rate (ETR), while reducing non-photochemical heat dissipation (NPQ) by 61.0%, indicating superior light-use efficiency. Furthermore, 8R2B upregulated CAT and POD activities promoted soluble sugars (up 688.4% in leaves), soluble proteins, and ascorbic acid accumulation, yet reduced leaf nitrate by 28.5%. Principal component analysis confirmed 8R2B as the most effective formulation across all growth, photochemical, defense, and quality traits. These findings provide a novel, evidence-based 8:2 red-to-blue LED light recipe for high-yield, high-quality, and commercially viable purple celery production in controlled environment agriculture. Full article

Interferons (IFNs) are a family of cytokines which serve as the first line of defense against pathogen infections while also exerting critical immunomodulatory roles. IFNs can induce hundreds of IFN-stimulated genes (ISGs) with cell-specificity, yet a high-resolution comparison of time-serial ISG induction across cell types is lacking. By using RNA sequencing, we conducted a comparative transcriptomic profiling during time-serial IFN-γ stimulation for up to 24 h in HeLa and HEK293T cells, the two most widely used immortalized human cell lines. We uncovered remarkably stronger IFN responses in HeLa cells, regarding the global transcriptomic dynamics, the number of induced ISGs, and the level of ISG expression. Both cell lines share a core set of ISGs associated with canonical JAK-STAT signaling, yet HeLa uniquely activates additional inflammatory and adaptive immunity-related pathways. Despite the much weaker IFN response in HEK293T cells, we also identified a few HEK293T-specific ISGs, including several with crucial immune-related functions. Notably, transposable elements—including many adjacent to ISGs—are also highly up-regulated in HeLa cells, implying their potential links to ISG induction. Collectively, this study provides a high-resolution temporal atlas of IFN-γ-stimulated transcriptomic dynamics in HeLa and HEK293T cells, revealing the shared core module and cell-specific patterns of their interferon responses. Full article

Heat stress is one of the most prevalent and unavoidable environmental stressors in modern aquaculture and natural fishery ecosystems. With the intensification of global warming, the frequency, intensity, and duration of extreme heat events have increased substantially, progressively reducing the thermal safety margin of fish. As ectothermic vertebrates, fish rely heavily on ambient water temperature to maintain physiological functions and metabolic homeostasis. Elevated temperatures can induce profound metabolic reprogramming, characterized by suppressed protein deposition, enhanced lipid mobilization, and altered glucose metabolism, while simultaneously causing structural damage and functional dysfunction in critical organs and tissues such as the liver, intestine, gills, and reproductive system. Heat stress also activates the stress axis and oxidative stress responses, often leading to immunosuppression and disruption of antioxidant defenses, ultimately impairing growth performance, behavior, reproduction, and survival. This review focuses on fish and summarizes the major physiological injuries, molecular regulatory pathways, and adaptive strategies associated with heat stress under global warming. Comparative evidence from crustaceans and molluscs is used only where it helps clarify shared or divergent responses among aquatic ectotherms. Full article

To address the need for effective biocontrol of poplar anthracnose caused by Colletotrichum gloeosporioides, in this study, 20 Trichoderma strains were isolated from the rhizosphere of seven tree species on Tianzhu Mountain to screen for potent growth-promoting and antifungal agents. The inhibitory effects of the strains on C. gloeosporioides (Cgl) were evaluated through mycelial growth assays, volatile organic compound tests, and fermentation filtrate analysis, while their growth-promoting capabilities and induction of systemic resistance were assessed in poplar seedlings via biomass measurement, stomatal analysis, and gene expression profiling. The results demonstrated that T. asperelloides Tas369 significantly inhibited pathogen growth and improved seedling growth, increasing stomatal density by 134% and inducing phenylalanine ammonia-lyase (PAL) and peroxidase (POD) enzyme activities. Notably, Trichoderma composite (Tcom) outperformed single-strain treatments, achieving 89.8% control efficacy, reducing the malondialdehyde content by 1.1 mmol/g, and significantly upregulating the key defense genes NPR1 (14.32-fold) and PR1-1 (219.79-fold) through increased activity of the salicylic and jasmonic acid signalling pathways. In conclusion, while Tas369 exhibits strong individual potential, the Tcom consortium provides superior biocontrol through multiple mechanistic interactions, offering an effective and sustainable approach for managing poplar anthracnose in forestry applications. Full article

Kiwifruit bacterial canker, caused by Pseudomonas syringae pv. actinidiae (Psa), severely restricts the sustainable development of the kiwifruit industry. Screening stable resistant germplasm and establishing efficient disease resistance evaluation methods are core prerequisites for breeding resistant cultivars. In this study, 86 Actinidia accessions were systematically assessed for Psa susceptibility over three consecutive years using the reported detached shoot inoculation assay. Seven representative accessions with contrasting resistance phenotypes, namely ‘Cuiyu’, ‘Chuhong’, ‘Jinmei’, ‘Hongyang’, ‘Cuixiang’, ‘Avfs08’, and ‘G3’, were selected to measure the activities of four defense-related enzymes post Psa inoculation to dissect the physiological mechanisms driving divergent Psa resistance in kiwifruit. Lesion lengths across years exhibited a significant positive correlation, demonstrating that this inoculation method delivers repeatable, genetically stable phenotypic data with limited environmental interference. Two accessions belonging to A. valvata and A. eriantha exhibited stable high resistance via synergistic biochemical defenses. By contrast, the widely grown cultivar ‘Hongyang’ was highly susceptible, while moderately resistant materials such as ‘Cuiyu’ and ‘Yannong 3’ were discovered within the inherently susceptible species A. chinensis. Highly resistant accessions rapidly induced coordinated increases in SOD and PAL activity at 24 h post inoculation to maintain ROS homeostasis and lignin biosynthesis, whereas susceptible accessions displayed chaotic, ineffective enzymatic stress responses. Temporal synergy of PAL and POD may act as the key defensive regulatory mode. This study uncovered substantial interspecific variation in Psa resistance across Actinidia germplasm, identified elite donors with stable resistance, and elucidated the physiological mechanisms of kiwifruit resistance to Psa. These findings provided a theoretical foundation and valuable germplasm for subsequent resistance gene mining and disease resistance breeding. Full article

C-type lectins (CTLs) are important pattern recognition receptors (PRRs) involved in innate immune defense in crustaceans. In this study, a novel C-type lectin, designated LvCTL, was identified and functionally characterized from Litopenaeus vannamei. Sequence analysis revealed that the open reading frame (ORF) of LvCTL is 495 bp in length and encodes a 164-amino acid polypeptide containing a typical C-type lectin-like domain but lacking the classical carbohydrate-binding motifs. Notably, two novel EPF motifs were identified in the CTLD region, suggesting a potential non-canonical ligand recognition pattern. Phylogenetic analysis revealed that LvCTL clustered with other crustacean CTLs. Tissue expression analysis revealed that LvCTL exhibited the highest transcript level in the hepatopancreas. After immune stimulation, LvCTL expression in the hepatopancreas was significantly regulated by LPS, Vibrio parahaemolyticus, Staphylococcus aureus, WSSV and Poly(I: C), indicating its involvement in antimicrobial immune responses. RNA interference assays showed that knockdown of LvCTL significantly increased the bacterial burden and reduced the survival rate of shrimp after V. parahaemolyticus infection. Furthermore, recombinant LvCTL displayed broad bacterial binding activity to Gram-negative and Gram-positive bacteria and induced calcium-dependent agglutination of V. parahaemolyticus and S. aureus. Taken together, these results demonstrate that LvCTL functions as an important immune recognition molecule and contributes to antibacterial defense against V. parahaemolyticus in L. vannamei. These findings broaden our understanding of the functional diversity of shrimp CTLs and their contributions to crustacean innate immunity. Full article

The successful use of Assisted Reproductive Technologies (ARTs) such as artificial insemination (AI) in small ruminants and other mammals depends on many factors, the most important of which is the quality of the semen used. The liquid storage and cryopreservation of spermatozoa at lower temperatures are associated with artificial insemination and rapid genetic improvement programs in the sheep production industry. Several studies have reported increased lipid peroxidation (LPO) and highly reactive oxygen species (ROS) production during liquid storage or cryopreservation of ram semen, leading to oxidative stress (OS), decreased antioxidant defense, and changes in sperm quality parameters like biokinetic and biochemical characteristics, viability, functional membrane and DNA integrity, along with mitochondrial activity. Therefore, supplementing ram semen extenders with exogenous antioxidants before preservation could mitigate this harmful effect. Various in vitro studies have reported improvements in ram sperm quality parameters like motility indexes, vitality, functional membrane/DNA integrity, antioxidant enzyme activity, total antioxidant content, mitochondrial activity, in vivo/in vitro fertility with significant decline in sperm abnormality, free radical production, LPO, ROS, apoptosis rate, and cytochrome C release from the mitochondrial matrix after the addition of various natural and synthetic antioxidant (vitamins, glutathione, taurine, pyruvate, melatonin, cysteine, selenium, zinc, plant extracts, sugars, amino acids, polyphenols) substances during preservation. Therefore, this review summarizes recent findings on oxidative stress-induced damage to sperm quality parameters in various ram breeds during chilling storage and cryopreservation. Moreover, supplementing basic semen extenders with different non-enzymatic antioxidant substances as a method to maintain sperm quality—along with their efficacy in reducing or preventing sperm damage during preservation—was discussed in detail. Full article

Spot blotch has become a major devastating disease in wheat. In the current study, Faisalabad-08 was supplemented with various levels of selenium (Se) both in vitro and in greenhouse experiments (CRD, n = 3) to counter the spot blotch pathogen. The results revealed that minimum disease incidence was assessed in the case of T₂ (50 mg L⁻¹). However, maximum plant growth attributes, including plant height (PH), plant fresh weight (PFW), plant dry weight (PDW), leaf surface area (LSA), and root length (RL), were recorded in T₅ (50 mg L⁻¹ + pathogen). Similarly, chlorophyll a, chlorophyll b, total chlorophyll, membrane stability index, carotenoid, relative water contents, proline, sugar, flavonoid, total phenolic content, SOD, POD, CAT, PPO, and PAL contents were enhanced in T₅ compared to other tested treatments. However, MDA, an oxidative damage marker, was significantly decreased with T₅. Correlation, PCA, and heatmap analysis suggested that all the attributes were significantly interrelated, except MDA, in defining the crop’s potential to sustain its growth under biotic stress. In crux, foliar Se application (50 mg L⁻¹) effectively mitigates spot blotch through enhanced antioxidant defense and physiological homeostasis. This sustainable approach offers a viable alternative to conventional fungicides for integrated wheat disease management. Full article

The Taiwan loach (Paramisgurnus dabryanus ssp. Taiwan) is a popular cultured fish in southern China due to its rich nutritional content and rapid growth. Oxidative stress and homeostatic imbalance induced by low temperature are among the key factors restricting its large-scale aquaculture. Therefore, it is of great significance to investigate the oxidative stress damage and the adaptive mechanisms employed by this species in response to low temperature. In this study, the water temperature was lowered from 24 °C to 8 °C at a rate of 2 °C/h. Afterwards, the temperature was held at 8 °C for two durations: 12 h and 48 h. Antioxidant indices indicated that the Taiwan loach suffered from oxidative stress damage at the 12 h stage, but the antioxidant enzyme defense system was not fully activated. As the cold stress extended to 48 h, the activities of total superoxide dismutase (T-SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) increased significantly (p < 0.01). Histological observations revealed that the livers exhibited cellular vacuolation, sinusoid congestion and karyolysis under cold stress. Transcriptomic data revealed that the Taiwan loach underwent adaptive alterations in response to low temperature through diverse pathways. We speculate that, at low temperature, the Taiwan loach may, on the one hand, regulate lipid metabolism to maintain cell membrane fluidity and meet energy demands, and, on the other hand, reprogram protein synthesis and processing to avert the overaccumulation of misfolded proteins. In addition, it also adopts a strategy of lysine and polyamine accumulation. This study provides a novel theoretical basis for breeding cold-tolerant varieties of Taiwan loach and optimizing overwintering aquaculture management. Full article

Populus hopeiensis is an important native poplar species in northern China, but herbivorous insect damage seriously affects its growth and ecological function. WRKY transcription factors play important roles in plant stress responses; however, the function of WRKY23 homologs in woody plant resistance to chewing herbivores remains unclear. In this study, a herbivore-responsive WRKY transcription factor gene, PhWRKY23, was identified from P. hopeiensis. PhWRKY23 expression was significantly induced by Spodoptera litura feeding, with a maximum increase of approximately 69.71-fold the control level at the highest damage level, and the encoded protein was predominantly localized in the nucleus. To investigate its function, PhWRKY23-overexpressing and RNA interference transgenic lines were generated. In the choice feeding assay, the consumed leaf area of PhWRKY23-overexpressing plants was approximately 85.5% lower than that of WT plants after 8 h. In the no-choice feeding assay, the total larval mass after 6 d was approximately 38.8% lower in larvae fed on overexpression plants and 51.0% higher in larvae fed on RNAi plants than in those fed on WT plants. Physiological analysis showed that RNAi plants accumulated significantly more MDA than WT and overexpression plants, whereas overexpression plants had higher chlorophyll a, chlorophyll b, and carotenoid contents than the other genotypes. Phytohormone analysis further showed that PhWRKY23-overexpressing plants accumulated higher levels of jasmonic acid, jasmonoyl-L-isoleucine, and salicylic acid, whereas abscisic acid showed no significant difference among genotypes. Yeast two-hybrid screening identified several candidate PhWRKY23-interacting proteins, and pairwise validation confirmed that PhWRKY23 interacted with PhDOX1 in yeast. These results indicate that PhWRKY23 positively contributes to herbivore resistance in P. hopeiensis and that this resistance phenotype is associated with changes in JA, JA-Ile, and SA accumulation and defense-related physiological traits. Full article

Vascular calcification (VC) is a major complication of chronic kidney disease (CKD) that is strongly associated with cardiovascular mortality. While indoxyl sulfate (IS), a protein-bound uremic toxin, has been implicated in the progression of VC, the underlying molecular mechanisms remain unclear. We investigated the procalcific effects of IS using a two-step nephrectomy-induced CKD mouse model and cultured vascular smooth muscle cells. In vivo, progressive renal impairment was associated with elevated circulating IS levels and enhanced VC. In vitro, IS dose- and time-dependently induced calcium deposition, increased reactive oxygen species (ROS) production, and upregulated osteogenic markers, including runt-related transcription factor 2 (RUNX2), bone morphogenetic protein 2 (BMP2), and osteocalcin (OCN), whereas N-acetyl-L-cysteine (NAC) partially attenuated IS-induced ROS accumulation and cell injury. Mechanistically, IS exposure activated extracellular signal-regulated kinase (ERK) and Wnt/β-catenin signaling while suppressing nuclear factor erythroid 2-related factor 2 (Nrf2)-related antioxidant responses, as reflected by reductions in the phosphorylated Nrf2 (pNrf2) to total Nrf2 and heme oxygenase-1 (HO-1) expression. Pharmacological inhibition of ERK and Wnt/β-catenin signaling attenuated IS-induced osteogenic responses. These findings indicate that IS promotes VC in association with increased oxidative stress, activation of ERK and Wnt/β-catenin signaling, and impaired Nrf2-related antioxidant defense. These integrated findings provide mechanistic insight into IS-associated VC and highlight oxidative stress-related signaling networks as potential therapeutic targets in CKD. Full article

Ultraviolet B (UVB) irradiation is a major environmental factor contributing to skin photoaging by inducing oxidative stress, apoptosis, inflammation, and extracellular matrix degradation in dermal fibroblasts. This study investigated the photoprotective effects of Thua Nao, a Thai fermented soybean, against UVB-induced human dermal fibroblast damage, and explores its underlying mechanisms. The dichloromethane fraction of Thua Nao (TN-DC) most effectively mitigated UVB-induced cell death. HPLC analysis identified daidzein and glycitein as the major constituent isoflavones in TN-DC that protect fibroblasts against UVB-induced cellular damage. Mechanistically, they reduced apoptosis by suppressing caspase-9/3 activation and preserving mitochondrial membrane potential. Additionally, they suppressed inflammatory mediators (IL-6, IL-8, iNOS, COX-2) and prevented collagen loss. These protective outcomes correlated with decreased intracellular reactive oxygen species and upregulated endogenous antioxidant enzymes (SOD-1, HO-1). Signaling pathway analysis revealed that TN-DC activated the pro-survival ERK1/2 and Akt pathways in UVB-exposed cells. Conversely, daidzein and glycitein selectively attenuated JNK MAPK activation, downregulating downstream pro-inflammatory cytokines and mediators. Collectively, these findings demonstrate that TN-DC protects human dermal fibroblasts against UVB-induced photoaging primarily by enhancing endogenous antioxidant defense, thereby preserving cellular homeostasis through coordinated regulation of oxidative stress-responsive signaling pathways. Full article

Lead (Pb) is a widespread environmental pollutant that induces systemic toxicity in aquatic organisms primarily through oxidative stress, hematological disruption, and immune dysfunction. This study investigated the protective effects of ellagic acid (EA) against Pb-induced toxicity in common carp (Cyprinus carpio) using a multi-biomarker approach and molecular docking. Fish were assigned to six experimental groups: control, EA-treated, Pb-I, Pb-I + EA, Pb-II, and Pb-II + EA. Fish in the Pb-I and Pb-II groups were exposed to 2.5 and 5 mg/L Pb, respectively, while EA was administered via diet at 100 mg/kg for 14 days. At the end of the exposure period, hematological indices, innate immune parameters, and oxidative stress biomarkers were assessed in blood, liver, kidney, and gill tissues. Pb exposure caused marked hematological impairment, suppressed immune responses, increased malondialdehyde levels, and disrupted antioxidant defense by reducing SOD, CAT, GSH-Px, and GSH levels while increasing GST activity. In contrast, dietary EA supplementation significantly mitigated Pb-induced alterations, improved hematological and immunological responses, reduced lipid peroxidation, restored antioxidant capacity, and normalized GST activity to control levels. Molecular docking analyses further showed that EA interacts with hemoglobin and immunoglobulin M, supporting its potential role in preserving oxygen transport and immune functions under Pb-induced stress. Overall, the findings demonstrate that Pb-induced toxicity involves coordinated disruption of redox homeostasis and immune function, whereas EA exerts a multi-target protective effect through biochemical and molecular mechanisms. This study provides mechanistic insight into chemical–biological interactions and supports the potential application of natural bioactive compounds in mitigating heavy metal-induced toxicity. Full article

Superoxide dismutase 2 (SOD2), a key mitochondrial antioxidant enzyme, is essential for maintaining cellular redox homeostasis by scavenging superoxide radicals. While viruses often induce oxidative stress, the specific role of SOD2 in antiviral defense remains unclear. Here, we report that vaccinia virus (VACV) infection triggers mitochondrial and cellular reactive oxygen species (ROS) and selectively upregulates SOD2, but not SOD1. Genetic knockout of SOD2 exacerbated mitochondrial ROS (mtROS) accumulation and significantly enhanced VACV replication and spread, resulting in larger viral plaques. Conversely, SOD2 overexpression constrained plaque formation and suppressed viral dissemination. Mechanistically, the antiviral function of SOD2 does not strictly rely on its enzymatic activity or mitochondrial targeting, as neither the deacetylation-mimicking mutant nor the mutant lacking the mitochondrial localization signal peptide appreciably impaired its antiviral potency. Furthermore, in a rabbit model, local overexpression of human SOD2 attenuated the poxvirus lesion formation. Our findings unveil an important yet easily overlooked role of SOD2 in antiviral defense and posit it as a promising candidate for the development of host-directed therapeutics against poxviruses. Full article