Search Results (11,665)

It is difficult to effectively evaluate the technology used to test fatigue in face gears due to their complexity, the lack of experimental data, and weak life evaluation methods. In this paper, we study fatigue experiment technology and carry out a life evaluation for hot rolling straight face gears. A hot rolling forming test was completed by analyzing and simulating the rolling formation of face gears, and the bending stress and fatigue life of face gears was simulated. We designed an experimental scheme and test bench for testing fatigue in straight face gears; this is the first bending fatigue life experiment carried out on hot rolling straight face gears in China. The BP neural network–Bootstrap sample expansion method and GM(1,1) model were carried out to evaluate the fatigue life of hot rolling straight face gears under information-poor conditions. A comparative analysis was carried out with skiving-formed straight face gears, which verifies the feasibility and superiority of hot rolling forming for straight face gears. This study provides a theoretical basis and technological support for the study of fatigue resistance in face gears, and applications for machine installations are provided. Full article

Fungi of the Phallales order are globally distributed and are important in forest ecosystems, and many species have medicinal and edible value. However, despite the rich diversity, the information on this order is limited, and its taxonomic classification remains contentious. In this study, the mitogenomes of five species from the Phallales order were sequenced, assembled, annotated, and compared. All five assembled mitogenomes were circular, ranging in size from 41,465 bp to 99,150 bp. Introns and intergenic regions were the key factors for mitogenome size variation in the Phallales order. The arrangement of 15 protein-coding genes, 2 rRNA genes, and 24 tRNA genes was highly conserved among the Phallales species. The only variation observed was the presence of an additional copy of trnI, trnT, trnD, and trnF in some mitogenomes. Specifically, the mitogenomes of P. rugulosus, P. hadriani, P. rigidiindusiatus, and P. dongsun had an additional copy of trnI, trnT, trnD, and trnF, respectively. A phylogenetic analysis produced well-supported phylogenetic tree, indicating that the mitogenome was an effective molecular marker for inferring evolutionary relationships. The phylogenetic analysis showed that the Phallales and Gomphales species share a closer evolutionary relationship. Our results contribute to a better understanding of the evolutionary dynamics, genetic constitution, and systematic classification of this important fungal community. Full article

Establishment of sister chromatid cohesion N-acetyltransferase 2 (ESCO2) is an acetyltransferase involved in sister chromatid cohesion. Here we demonstrated that ESCO2 has a new role in telomere maintenance through its binding with telomeric repeat-binding factor TRF1 and TRF2. Loss of ESCO2 induces aberrant DNA damage at telomeres and leads to dramatic telomere shortening. ESCO2 associates with several proteins involved in DNA replication and repair, including BLM, WRN, TopBP1, BRIP1, BRCA1, and MUS81. Moreover, we show that ESCO2 acts in epistasis with BLM in promoting telomere stability. Taken together, our data suggest that ESCO2 is required for the maintenance of telomere stability, presumably by coordinating multiple replication and repair factors to facilitate telomere replication and protection. Full article

Screening superior hosts is critical for artificial cultivation of Cistanche deserticola Y.C.Ma. However, intraspecific trait variation and host suitability of its emerging host Atriplex canescens (Pursh) Nutt remain unsystematically evaluated. In this study, 31 A. canescens individuals with diverse morphotypes and parasitic statuses were selected from over 300 seedlings. After post-transplant assessment, 17 representative A. canescens genotypes were selected and cutting-propagated. Their genetic, phenotypic and photosynthetic traits were systematically analyzed by multiple approaches, with a multi-indicator evaluation system built by correlation analysis and entropy-weighted Technique for Order Preference by Similarity to Ideal Solution)(TOPSIS). The results showed that the Internal Transcribed Spacer(ITS) sequences of the selected genotypes had an approximate length of 644 bp, exhibiting an average GC contents of 58.35%. A total of 22 haplotypes were detected, indicating high genetic diversity. In this study, superior host genotypes were defined as those with relatively excellent growth potential and stable, efficient photosynthetic performance. NP3.13, P3.1 and NP2.23 were recognized as promising candidate host genotypes with potential for C. deserticola cultivation, and their host suitability was indirectly inferred from their relatively superior growth and photosynthetic traits. This study not only provides valuable candidate germplasm resources and a scientific basis for optimizing the cultivation of C. deserticola, but also furnishes methodological support for elite genotypes screening in other plant species by the established evaluation framework. Full article

Traditional methods for geostressfield inversion face issues such as weak physical interpretability and insufficient generalization ability. This study pioneers the application of Physics-Informed Neural Network (PINN) to this problem, developing a data- and physics-driven inversion algorithm. The framework incorporates a constitutive-equation-based regularized loss function as a hard constraint during training to ensure physical consistency. To address boundary load uncertainty, two quantification approaches—Bayesian linear regression and surrogate model optimization—are proposed to establish 95% confidence intervals for boundary coefficients. Verification based on simple three-dimensional models and actual geological models of mines shows that PINN inversion achieves a mean absolute relative error as low as 0.0772%, with an error of 15.67% under sparse sampling conditions—significantly lower than the 31.07% error of the traditional Back propagation neural network. This demonstrates excellent robustness and data efficiency. In the practical engineering application of complex geological bodies, the average error of principal stress inversion is 9.35% with a minimum error of 0.137%. All inversion results fall within the permissible accuracy range of engineering, and the stress distribution conforms to basic laws, with an average error of 0.453 in the constitutive relation. Compared with BP neural network and multiple linear regression methods, it shows obvious accuracy advantages. This method provides a new solution for intelligent ground stress prediction with high accuracy, high efficiency, and strong physical interpretability, and also lays the foundation for early identification of geological disasters. Full article

Leptobotia rotundilobus is a newly described species in the subfamily Leptobotinae (Teleostei: Cypriniformes), which is endemic to China. Research on this recently discovered species is preliminary, characterized by limited baseline data and the absence of a fully sequenced mitochondrial genome. To elucidate the structural features of the mitochondrial genome of L. rotundilobus, we performed whole-genome sequencing using next-generation sequencing technology and analyzed its genomic composition, gene content, and structural variation through genome assembly and bioinformatics. The complete circular sequence, spanning 16,593 bp, comprises 13 protein-coding genes (PCGs), two ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes, and a typical control region (D-loop), all arranged in the canonical order. The overall base composition of the genome was determined to be 30.8% adenine (A), 24.4% thymine (T), 28.6% cytosine (C), and 16.2% guanine (G). This A+T bias (55.2%) is consistent with the mitochondrial genomes of other Leptobotia, which may affect secondary structure. The ratio of non-synonymous (Ka) to synonymous substitutions (Ks) of 13 PCGs of 16 Leptobotinae species is far less than 1 (0.012–0.063), indicating strong negative or purifying selection on the mitogenome in these species. Moreover, to investigate the phylogenetic relationships within the subfamily Leptobotinae, particularly within the genus Leptobotia, we constructed multiple phylogenetic trees of the mitogenome and concatenated 13 PCGs of 39 sequences with Sinibotia superciliaris as an outgroup. The phylogentic trees using the maximum likelihood (ML) and Bayesian inference (BI) methods consistently indicate that: (1) after correcting the species identification error, L. rotundilobus is closely related to L. micra; and (2) the species of Leptobotia and Parabotia each form a monophyletic group. This study provides new insights into the taxonomy and phylogenetic relationships of Leptobotinae, with a particular focus on the genus Leptobotia, thereby contributing to the clarification of the systematics, origin, and evolution of Botiidae. Full article

Tributyrin (TB), as a novel feed additive, holds broad market prospects and is crucial for promoting fish growth and maintaining intestinal health. We first identified the fatty acid metabolism-related gene cpt1b in the intestines of mandarin fish (Siniperca chuatsi) from the TB-supplemented group. A total of 600 mandarin fish (200.0 ± 5.0 g) were evenly allocated into three groups. The control group (C) received only the standard extruded feed, while the experimental groups were supplemented with tributyrin (TB) at concentrations of 500 mg/kg (T1 group) and 1000 mg/kg (T2 group), respectively. Cloning yielded a 2364 bp open reading frame (ORF) encoding 787 amino acids, with the gene possessing two conserved transmembrane domains. Phylogenetic analysis further indicated a close phylogenetic relationship between largemouth blackbass (Micropterus salmoides) and mandarin fish. Tissue distribution and intestinal enzyme activity analyses revealed that supplementation with varying concentrations of TB upregulates cpt1b gene expression in different tissues, while modulating intestinal digestive enzyme and antioxidant enzyme activities. Our findings suggest a potential mechanism involving enhanced intestinal enzyme activity, reduced fat accumulation, increased expression of lipid oxidation-related genes, and accelerated TB degradation in the intestine. Full article

Data on cardiac and hemodynamic parameters associated with preeclampsia (PE), particularly changes occurring in the immediate perioperative period, remain scarce. These changes are clinically important for the management of patients with severe PE or underlying cardiac dysfunction. Maternal hemodynamics undergo substantial alterations during cesarean section (CS) as a result of sympathetic blockade induced by spinal anesthesia, the vasodilatory effects of general anesthetics, and changes in blood flow related to aortocaval compression in the supine position and during delivery. Massive hemorrhage represents an additional factor contributing to these alterations. In routine clinical practice, maternal heart rate (HR) and blood pressure (BP) are monitored to assess circulatory status. However, a more precise evaluation can be achieved by measuring stroke volume (SV), cardiac output (CO), and systemic vascular resistance (SVR). These parameters are particularly relevant in cases of severe hemorrhage or hypertension, as they may facilitate targeted hemodynamic management. Overall, hemodynamic responses to cesarean delivery under spinal anesthesia appear to differ between normotensive and hypertensive pregnancies. Normotensive parturients seem to be more susceptible to pronounced hypotension following sympathetic blockade, whereas hypertensive disorders of pregnancy are associated with altered vascular reactivity and modified intraoperative hemodynamic responses. Nevertheless, interpretation of these findings remains limited by the heterogeneity of the available studies and the lack of quantitative evidence synthesis. Full article

Fat deposition plays a crucial role in regulating the production performance and meat quality of broilers. Although the heterogeneity of mammalian adipocytes has been extensively studied, research on the molecular mechanisms underlying differences in lipid droplet accumulation in avian adipocytes remains limited. This study confirmed a significant positive correlation (R² > 0.81, p < 0.001) between the SSC signal and lipid droplet content via fluorescence staining of lipid droplets, Oil Red O staining, and triglyceride (TG) quantification. Based on this, a label-free sorting strategy using SSC signals was established to sort differentiated chicken preadipocytes, obtaining high lipid droplet (H) and low lipid droplet (L) subpopulations, which were subsequently subjected to transcriptome sequencing and differential gene expression (DEG) analysis, followed by GO and KEGG enrichment analysis. The results indicated no significant differences in the expression of adipogenesis marker genes (PPARG, LPL, CD36, PLIN1, PLIN2) between the high lipid droplet (H) and low lipid droplet (L) groups, suggesting that both groups are at similar stages of differentiation. KEGG analysis revealed that both the H vs. NC and L vs. NC comparisons were enriched in common pathways, including the PPAR signaling pathway, ECM–receptor interaction, focal adhesion, cytokine–receptor interaction, and calcium–Apelin signaling pathway, suggesting that both groups of cells had activated the adipogenesis program. GO analysis showed that, in both H vs. NC and L vs. NC comparisons, differentially expressed genes (DEGs) were enriched in biological processes (BPs) related to cell adhesion, nucleosome assembly, chromatin remodeling, and receptor activity, as well as cellular components (CCs) such as the extracellular matrix, cytoskeleton, and nucleosome organization, indicating extensive gene reprogramming and activation of signaling transduction during differentiation. In the H vs. L comparison, enriched pathways included ABC transporters, ECM–receptor interaction, focal adhesion, gap junctions, microtubule-related processes, and neuroactive ligand–receptor interactions, involving lipid transmembrane transport, cytoskeleton stabilization, and signal transduction regulation, suggesting that high lipid droplet cells are more mature in lipid droplet transport, storage, and homeostasis maintenance. GO enrichment results further supported this conclusion, as H vs. L specifically enriched processes related to microtubule-related processes, cell cycle, and redox reactions (BPs), as well as chromosome organization, cytoskeleton, and motor activity (CC/MF), indicating that high lipid droplet cells maintain lipid droplet fusion and metabolic homeostasis via enhanced microtubule transport and antioxidant regulation. Differential gene analysis revealed that the L group upregulated genes associated with fatty acid synthesis and elongation (ACACA, FASN, SCD, FADS2, ELOVL1), cholesterol and isoprenoid biosynthesis (HMGCR, SQLE, MSMO1, DHCR7, DHCR24, FDPS, LSS), and fatty acid oxidation (PPARA, PPARD, ACAD11, SIRT5), reflecting a metabolic characteristic of concurrent lipid synthesis and mobilization; the H group, conversely, upregulated genes associated with lipid droplet formation and storage (G0S2, MOGAT1, GPAT4, PLIN4, AUP1), lipid transport (ABCA1, ABCA2, ABCG1, OSBPL3, VLDLR), and antioxidant defense (GPX3, GPX4, HMOX1), exhibiting a storage and homeostasis-oriented metabolic state. In the NC, L, and H groups, the expression of five genes—GEM, SPP1, ABCA1, PDLIM3, and ITGA8—showed a gradual increase, suggesting that these genes were associated with preadipocyte differentiation and lipid droplet deposition. In summary, although the high and low lipid droplet subpopulations of chicken preadipocytes exhibit similar differentiation states, they form distinct metabolic orientations. The L group is characterized by active lipid synthesis, fatty acid oxidation, and membrane lipid remodeling, while the H group predominantly features lipid droplet storage, lipid transport, and antioxidant homeostasis. This study highlights the molecular mechanisms underlying the metabolic heterogeneity of avian adipocytes and provides a theoretical basis for poultry fat deposition regulation and genetic improvement. Full article

Background: Autophagy is a conserved intracellular degradation pathway essential for maintaining cellular homeostasis by recycling damaged organelles and proteins. Dysregulation of autophagy has been implicated in pregnancy-related complications such as preeclampsia and fetal growth restriction, underscoring its importance in maternal and fetal health. However, the autophagy status in the placental tissue of COVID-19-infected pregnant women remains unknown. Objective: To investigate autophagy activity in term placentas from pregnant women infected with COVID-19 compared to those from uninfected control pregnant women. Methods: In this prospective cross-sectional single-center study, 15 COVID-19-positive and 15 COVID-19-negative term pregnant women who delivered at Sultan Qaboos University Hospital between January 2020 and December 2022 were included. Immediately after delivery, the placental tissue samples were collected and assessed for autophagy activity using immunohistochemistry for LC3B and p62 markers, histopathological examination, and transmission electron microscopy. The proportion and intensity of LC3B and p62 staining were quantified. Statistical analysis was performed using the Mann–Whitney U test. Results: There was a significant reduction in p62 and LC3B expression in both the proportion and intensity in COVID-19 placentas compared to the control group. The proportion of p62 (p = 0.001) and LC3B (U = 46.000, p = 0.003) was significantly reduced in infected placentas. Similarly, intensity levels of both markers showed significant differences (p < 0.05), supporting the evidence of reduced LC3B/p62, suggesting autophagy modulation in COVID-19 patients’ placentas. Additionally, abnormal ultrastructural changes were observed in COVID-19–positive placentas, including mitochondrial injury, endoplasmic reticulum stress, microvillus loss, and basement membrane thickening. Conclusion: The study results from a limited sample size demonstrate a significantly altered autophagy flux in the placental tissues of term pregnant women with COVID-19 infection. These findings highlight the potential impact of COVID-19 infection on placental function and fetal development and underscore the need for further investigation into autophagy-modulating strategies to improve maternal–fetal health. Full article

With the rapid and exponential expansion of the lithium-ion battery (LIB) market, a new regulatory framework has been introduced, centered on the implementation of a Battery Passport (BP) to enhance transparency, traceability, and sustainability across the battery value chain. This review aims to provide the context in which the BP is being implemented by discussing the reliance of LIBs on critical raw materials (CRMs), as well as the related economic and regulatory aspects of the BP system. Furthermore, it examines ongoing BP initiatives and pilot projects and discusses the challenges and opportunities associated with this tool, highlighting its central role in enabling a circular LIB economy in Europe. A critical analysis from a research-oriented perspective is also provided. Full article

Continuous blood pressure (BP) monitoring is essential for the prevention and management of cardiovascular diseases. Traditional cuff-based methods cause discomfort during repeated measurements, and wearable sensors require direct skin contact, limiting their applicability. Radar-based contactless BP measurement has emerged as a promising alternative. However, radar pulse wave (RPW) signals are susceptible to motion artifacts, respiratory interference, and environmental clutter, posing persistent challenges to estimation accuracy and robustness. In this paper, we propose MARU-MTL, a Mamba-enhanced multi-task learning framework for continuous BP estimation using a single millimeter-wave radar sensor. To address signal quality degradation, a Variational Autoencoder-based Signal Quality Index (VAE-SQI) mechanism is proposed to automatically screen RPW segments without manual annotation. To capture long-range temporal dependencies across cardiac cycles, we integrate a Bidirectional Mamba module into the bottleneck of a U-Net backbone, enabling linear-time sequence modeling with respect to the segment length. We also introduce a multi-task learning strategy that couples BP regression with arterial blood pressure waveform reconstruction to strengthen physiological consistency. Extensive experiments on two datasets comprising 55 subjects demonstrate that MARU-MTL achieves mean absolute errors of 3.87 mmHg and 2.93 mmHg for systolic and diastolic BP, respectively, meeting commonly used AAMI error thresholds and achieving metrics comparable to BHS Grade A. Full article

Intraspecific variation in mitogenomes has provided the resolution to distinguish between morphologically indistinguishable species and highlight cryptic speciation. This level of variation is underexplored in introduced marine algae. This study evaluated the mitogenomic variability of Gracilaria vermiculophylla, one of the most invasive red algae in the Northern Hemisphere. Nine mitogenomes, comprising seven newly generated complete mitogenomes from Korea, Japan, and Morocco, plus two publicly available mitogenomes, were included in our analysis. The mitogenomes were highly conserved, ranged from 26,064 to 26,178 bp in length, and contained 52 genes comprising 25 protein-coding genes, three rRNAs, and 24 tRNAs. Nucleotide composition showed a strong AT bias (71.6%), with AT skew and GC skew values of 0.050 and 0.014–0.021, respectively. Pairwise divergences of cox2, rnl and rns rRNA were remarkably low, in a range of 0–0.06%, suggesting alternate markers for determining recent introductions. The phylogenetic relationship based on protein-coding genes revealed three shallow groups in G. vermiculophylla, which were correlated with distribution: two C groups from warm temperate sites and one T group from cold temperate sites. This result highlights mitogenomics as a new tool for the deeper understanding of phylogeography and invasion genetics of marine red algae. Full article

Research on centennial-scale precipitation variability within the Australian summer monsoon (AUSM) remains limited, particularly regarding its driving mechanisms and the sustainability-relevant implications for long-term water security and climate adaptation. Here, we use the TraCE-21ka transient simulation, which credibly reproduces the centennial periodicities documented in Holocene proxy records, to attribute the physical drivers of AUSM centennial variability. Attribution is conducted by contrasting the all-forcing (AF) simulation with four single-forcing experiments that isolate the effects of orbital parameters, ice sheets, meltwater flux, and greenhouse gases. Among these experiments, the meltwater-forcing run best reproduces the centennial periodicities found in the AF simulation, indicating that meltwater input is the leading contributor to Holocene AUSM centennial variability. We further identify a dynamical pathway in which Atlantic Meridional Overturning Circulation (AMOC) variability acts as the key mediator linking meltwater perturbations to Australian hydroclimate. The enhanced AMOC amplitude during the meltwater interval (0.14 at 9–8 ka BP), compared with much weaker fluctuations during the non-meltwater interval (0.01 at 4–3 ka BP), is accompanied by a ~200-year periodicity in AUSM precipitation. This periodicity arises through an interhemispheric teleconnection: a strengthened AMOC cools Southern Hemisphere sea surface temperatures, reduces moisture availability for northern Australia, and promotes large-scale subsidence that suppresses monsoon rainfall. By contrast, during 4–3 ka BP, when meltwater forcing was negligible, weaker AMOC variability coincides with warmer Southern Hemisphere sea surface temperature (SST), favoring cyclonic circulation over northwestern Australia, enhanced moisture convergence, and stronger ascent, ultimately intensifying AUSM precipitation. Beyond advancing process understanding, these results provide a sustainability-oriented framework for interpreting low-frequency hydroclimate variability relevant to Australia’s water resources and climate adaptation. Specifically, the identified meltwater–AMOC–SST–AUSM pathway offers a physical basis for developing and evaluating long-horizon indicators of monsoon-driven rainfall variability, informing monitoring strategies and scenario planning for drought–flood risk management, water allocation, and climate-resilient infrastructure. By linking centennial-scale monsoon variability to an identifiable remote driver, this study contributes to quantifying and contextualizing natural hydroclimate variability that can confound near-term trends, thereby supporting more robust sustainability assessments, adaptation policy design, and integrated water-resource management under ongoing climate change. Full article

Bioactive peptides (BPs) and probiotics have attracted increasing attention in food and nutrition research for their roles in microbial metabolism and functional food development, with lactic acid bacteria (LAB) representing widely used probiotic microorganisms possessing well-characterized metabolic and peptide transport systems within the gut microbiota. This review summarizes current knowledge on food-derived BPs and their interactions with probiotic LAB, with a particular focus on peptide transport and utilization mechanisms, including oligopeptide permease (Opp) and di-/tripeptide permease (Dpp) systems. Sources and production methods of BPs are reviewed, along with experimental evidence describing peptide-supported microbial growth and metabolic responses. Relevant analytical approaches used for peptide characterization and functional assessment are also discussed. Most available evidence derives from controlled in vitro studies and primarily reflects microbial physiological responses rather than direct host-level effects. This review provides a mechanistic perspective on peptide–probiotic interactions in LAB and outlines research directions related to nitrogen utilization and microbial functional performance. Full article