Search Results (10,383)

Social media engagement drives both individual behavior and content dissemination, yet traditional analytics often reduce interactions to simple counts, obscuring the complex structures underlying user activity. In the highly competitive digital landscape, understanding how users interact with content is crucial for businesses aiming to optimize social media campaigns and maximize return on investment (ROI). Traditional engagement metrics, such as likes and shares, fail to capture the underlying structure and dynamics of user behavior. This study investigates the latent patterns of engagement by combining topological data analysis (TDA) with behavioral clustering across 100,000 posts on multiple platforms. Using persistent homology and k-nearest neighbour graphs, we reveal a primary bifurcation between Active (validation-focused) and Passive (consumption/propagation) users, nested four-strain substructures, and over 650 significant $H_1$ loops indicating recurring feedback cycles. Active users exhibit strong cluster cohesion and high engagement rates, while Passive users contribute broadly to content diffusion with slightly higher loop counts, highlighting distinct functional roles in social media dynamics. These findings provide a principled framework for targeting content, reinforcing feedback loops, and leveraging hub posts to amplify engagement. By linking topological structure to behavioral patterns, this work advances both the theoretical understanding of digital interaction and the practical design of more effective social media campaigns. Full article

Klebsiella pneumoniae, a member of the ESKAPEE group of priority pathogens, has become one of the most challenging bacterial pathogens in modern clinical practice, largely due to its multidrug resistance and the immune-evasive effect of its capsular polysaccharide (CPS). Phage-encoded depolymerases, which selectively degrade the capsular polysaccharide, have emerged as promising antimicrobial agents capable of restoring bacterial susceptibility to both immune clearance and phage infection. The fragment corresponding to the C-terminal region of a putative depolymerase of bacteriophage KlebP_144, namely DepKP144ΔC, was cloned, expressed in E. coli, and purified using immobilized metal affinity chromatography. DepKP144ΔC displays an enzymatic activity against capsular polysaccharides of 100% K1 capsular-type strains and 85% K2 capsular-type strains, including classical and hypervirulent isolates. It was demonstrated that this protein is capable of inhibiting K. pneumoniae biofilm formation, but it is unable to disrupt mature biofilms. In vivo experiments using a murine K. pneumoniae infection model further confirmed its therapeutic potential: treatment with DepKP144ΔC improved survival rate in mice infected with K2-type K. pneumoniae, indicating significant attenuation of bacterial virulence. Therefore, these results demonstrate the potential role of the C-terminal domain of the bacteriophage KP144 tail-fiber protein in phage entry and show that its carbohydrate-recognition motifs possess enzymatic activity against the Klebsiella capsular polysaccharides. Full article

Background: Cymbidium kanran ‘Zhushalan’ is a famous traditional Chinese orchid with high ornamental and economic value. As its market expands, there is a need to improve its key horticultural traits and stress resistance. Unfortunately, these traits are difficult to breed using traditional methods, and an optimal regeneration and genetic transformation system for C. kanran has yet to be established. Methods: This study evaluated the factors affecting Agrobacterium-mediated genetic transformation and regeneration of C. kanran ‘Zhushalan’ using rhizomes obtained from seedlings as receptor material. Results: The highest regeneration frequency was achieved after pre-cultivating the rhizomes in the dark on ½ MS medium for 10 days. The genetic transformation system was optimized as follows: Agrobacterium strain, EHA105; optimal concentration of Agrobacterium solution, OD₆₀₀ = 0.6; 100 mg·L⁻¹ acetosyringone; an infection time of no more than 40 min; and co-culturing for one to three days. Positive strains were screened using meropenem (15 mg·L⁻¹) and hygromycin (50 mg·L⁻¹) and confirmed through PCR and qRT-PCR. A transformation rate of 11.67% was achieved. Conclusions: An efficient regeneration and genetic transformation system for C. kanran ‘Zhushalan’ has been established for developing transgenic technologies. Our findings will stimulate research on functional genes and molecular breeding related to C. kanran. Full article

The field effectiveness of Trichogramma parasitoids (Hymenoptera: Trichogrammatidae) against lepidopteran pests is strongly influenced by temperature, which affects their development, survival, parasitism and reproductive performance. Understanding thermal requirements is therefore essential for optimizing mass rearing and release strategies. The present study evaluated the effects of five constant temperatures (25, 30, 33, 35, and 40 °C) on biological parameters of Trichogramma bourarachae Pintureau & Babault and two strains (S1 and S2) of T. cacoeciae Marchal reared on Ephestia kuehniella Zeller eggs. Emergence rates were higher between 25 °C and 33 °C for all tested parasitoids, decreased markedly at 35 °C for T. cacoeciae, whereas T. bourarachae emergence showed higher tolerance at 35 °C, and no emergence was recorded for all parasitoids at 40 °C. Parasitism capacity was strongly influenced by both temperature and parental thermal history. Trichogramma bourarachae exhibited its highest parasitism rate at 25 °C; however, females originating from the parental generation that developed at 30 °C maintained relatively high parasitism rates at elevated temperatures (30 to 35 °C). For T. cacoeciae S1, parental development at 30 °C enhanced offspring parasitism over a broader temperature range. Conversely, T. cacoeciae S2 achieved maximum parasitism when the parental generation developed at 25 °C, with high parasitism maintained at 25 °C, 30 °C, and 33 °C. At the species level, parasitism was highest between 25 °C and 33 °C, declined at 35 °C, and no parasitism was recorded at 40 °C due to the absence of survival. Within each species, however, strain-specific differences were observed, particularly at 35 °C, indicating variability in thermal tolerance and reproductive performance. Female longevity decreased with increasing temperature in all species and strains. However, individuals originating from parental generation that developed at 30 °C exhibited improved survival when exposed to elevated oviposition temperatures, indicating thermal acclimation. Increasing temperature induced a male-biased sex ratio in T. bourarachae, whereas T. cacoeciae maintained stable thelytokous reproduction across all treatments. These results emphasize the importance of thermal tolerance and parental thermal history for selecting suitable Trichogramma species and strains for mass rearing and field application for biological control under warming climatic conditions. Full article

Although numerous studies have focused on the potential application of heterotrophic nitrification–aerobic denitrification (HNAD) bacteria in wastewater treatment, research exploring their potential in aquaculture biofloc systems remains limited. In this study, a promising HNAD strain, identified as Stutzerimonas stutzeri MJ20, was isolated from mature biofloc. This strain efficiently utilized low-cost carbon sources (e.g., glucose) and small-molecule carbon sources (e.g., sodium acetate and sodium succinate). Under conditions with glucose as the carbon source, a carbon-to-nitrogen (C/N) ratio of 15, pH 6–9, temperature 25–35 °C, salinity 0–35‰, and shaker speed of 0–150 rpm, it achieved removal rates of 95–100% for NH₄⁺-N, NO₂⁻-N, and NO₃⁻-N at initial concentrations of 100 mg/L each. Even at higher concentrations (up to 200 mg/L NH₄⁺-N and 500 mg/L for both NO₂⁻-N and NO₃⁻-N), removal rates exceeded 99%. Under mixed nitrogen sources, strain MJ20 demonstrated efficient nitrogen removal, preferentially utilizing NH₄⁺-N, with only minimal and transient accumulation of nitrite and nitrate. Genomic analysis revealed that MJ20 carries key denitrification genes, including napA, nirS, norB and nosZ, and possesses complete pathways for nitrate reduction to nitrogen gas and ammonia assimilation, although typical autotrophic nitrification genes were not detected. Combined genomic data and autotrophic culture experiments indicated that, in addition to utilizing various organic carbon sources, the strain also exhibited certain autotrophic growth capabilities. Furthermore, MJ20 showed strong flocculation ability (flocculation rate > 96% within 16 h), sensitivity to multiple common antibiotics, and no toxicity to zebrafish, demonstrating favorable biosafety. In simulated seawater aquaculture wastewater with a C/N ratio of 5, it achieved a total nitrogen removal rate exceeding 94% within 72 h. These results indicate that strain MJ20 possesses comprehensive advantages, including efficient nitrogen removal, broad carbon source adaptability, strong environmental resilience, minimal accumulation of intermediate nitrogen products, excellent flocculation ability, and high biosafety. These traits highlight its potential for application in biofloc systems and in treating aquaculture tail water with a low C/N ratio. This study provides theoretical insights and practical guidance for screening HNAD bacteria suitable for biofloc systems. Full article

Oenococcus oeni (O. oeni) can initiate and complete the malolactic fermentation (MLF) process, which significantly improves wine quality. However, stress factors commonly encountered in wine, such as acid stress and ethanol stress, can hinder this process. Overexpression of certain key functional genes using genetic recombination technology can enhance the stress tolerance of O. oeni. In this study, the large-conductance mechanosensitive channel (mscl) gene was overexpressed in O. oeni SD-2a using genetic recombination technology. The results showed that overexpression of this gene enhanced the growth rate of O. oeni under 10% ethanol stress conditions. Physiological index measurements indicated that overexpression of this gene enhanced the control of cell membrane permeability in the recombinant strain at different time points under ethanol stress and altered cell membrane fluidity at these time points. Proteomic analysis after 12 h of treatment under 10% ethanol stress revealed that mscl overexpression significantly altered the protein expression pattern of O. oeni. The most significantly affected proteins included some cell membrane transporters (for sugars, lipids, amino acids, and nucleotides) and proteins involved in cell wall synthesis. These results suggest that mscl overexpression enhances the ethanol stress tolerance of O. oeni by altering its cell membrane properties and affecting the expression levels of proteins related to cell membrane transport and cell wall synthesis. This study provides a theoretical reference for obtaining O. oeni recombinant strains with enhanced stress tolerance through genetic recombination technology. Full article

Hydraulic fracturing of unconventional reservoirs requires accurate fracture monitoring for treatment optimization. Low-frequency distributed acoustic sensing (LF-DAS) in neighbor wells provides dense strain-rate observations, but gauge-length averaging limits spatial resolution and merges closely spaced fracture features. This study formulates gauge-length averaging as an explicit convolution operator and develops a regularized inversion method combining Tikhonov smoothing, a recursive prior, and L-curve parameter selection, supported by a semi-analytical multi-fracture forward model. On a synthetic benchmark, the method advances the effective resolution from the 10 m gauge-length scale to the 1 m sample-spacing scale, recovering fracture count in all hit-window time slices (versus 32% for raw data), achieving Pearson correlation of 0.80 versus 0.29, with peak-position error reduced by 47%. Noise-sensitivity analysis indicates a practical SNR floor near 20 dB, and Wiener-filter comparison confirms 1.5–2.7× correlation and 1.5–2.3× peak-count advantages across tested noise levels. Field application to HFTS-2 B1H stages 22 and 23 reveals previously hidden tensile features consistent with higher local fracture density. With per-stage processing in seconds and no extra sensing hardware, the method is well suited for near-real-time deployment. Full article

Sodium-ion batteries (SIBs) represent a compelling alternative to lithium-ion batteries for grid-scale energy storage, owing to the high natural abundance and low cost of sodium resources, as well as their strategic alignment with national energy security priorities. Nevertheless, the sluggish Na⁺ diffusion kinetics and limited specific capacity of anode materials continue to impede practical deployment. Herein, nitrogen-doped carbon-coated TiO₂ nanofibers (TiO₂/C-N) were rationally engineered through a facile electrospinning route integrated with synergistic defect and coating engineering. The in situ-formed N-doped carbon shell establishes a continuous, high-conductivity electron-transport network while simultaneously buffering volumetric strain during repeated (de)sodiation, thereby preserving long-term structural integrity. Electrochemical assessments demonstrate that the TiO₂/C-N electrode delivers a reversible specific capacity of 233.64 mAh g⁻¹ at 0.1 A g⁻¹ (initial Coulombic efficiency 54.13%). Quantitative kinetic analysis reveals a pronounced pseudocapacitive contribution of 41.4% at 1.2 mV s⁻¹, confirming a surface-controlled Na⁺ storage pathway that markedly enhances rate capability. Moreover, the electrode retains 245.5 mAh g⁻¹ after 150 cycles at 1 A g⁻¹, underscoring exceptional cycling stability. This work elucidates the synergistic regulation of N-doped carbon coating and pseudocapacitive kinetics in TiO₂-based anodes, offering a robust design strategy for high-rate, long-cycle-life SIB anodes. Full article

Background/Objective: Mental fatigue (MF) significantly impairs psychomotor performance in dynamic sports; however, its specific impact on closed-skill precision-demanding tasks remains underexplored. This study investigated the acute effects of experimentally induced MF exposure on psychophysiological responses, mood states, and archery shooting performance. Methods: Fifteen well-trained male compound-bow archers participated in a randomized crossover study. Participants completed an MF condition (30 min modified Stroop task) and a control condition (CON; passive viewing of a neutral documentary), separated by a 72 h washout period. Continuous heart rate (HR), archery shooting accuracy, ratings of perceived exertion (RPE), rating scale of mental effort (RSME), state anxiety (VAS-A), mood states, and exercise enjoyment scale (EES) were assessed. Results: The Stroop task successfully induced subjective MF. Consequently, shooting accuracy significantly deteriorated in the MF condition compared to that in the CON condition (p < 0.001; g = 0.731). While HR and VAS-A remained consistent across conditions, the MF condition elicited a significant increase in RPE (p = 0.007; g = 0.836) and RSME (p = 0.010; g = 0.794). Furthermore, MF significantly increased feelings of anger and fatigue while drastically reducing PACES (p < 0.001; g = 1.530). Conclusions: Acute MF significantly degrades fine motor accuracy in precision sports. The pronounced dissociation between elevated RPE and stable peripheral physiological strain suggests that performance decline is driven by top-down cognitive burden rather than physiological limitations. Therefore, systematic monitoring of cognitive load is crucial for optimizing performance in precision sports. Full article

The Low-Strain Pile Integrity Test (LSPIT), standardized in ASTM D5882, is widely used as a rapid and economical non-destructive technique for assessing pile continuity in deep foundation systems. However, interpretation of LSPIT reflectograms remains strongly dependent on expert judgment and is influenced by soil–pile interaction effects such as damping and radiation losses, which can alter waveform morphology and confound automated defect screening. This study proposes a soil-aware deep learning framework that combines image-based reflectogram features with categorical geotechnical context describing the dominant soil regime at the measurement site. Reflectogram images are processed with a pretrained ConvNeXt-Large backbone, while soil information derived from Unified Soil Classification System (USCS) logs is represented as a categorical auxiliary input and mapped to a learnable embedding. The resulting multimodal design conditions waveform interpretation based on site context rather than relying on signal morphology alone. The framework is examined on an assembled benchmark of 510 expert-labeled reflectograms (404 intact and 106 defective), including a nine-site subset of 182 field records with explicit soil annotations. On the assembled benchmark, the model yields 99.41% accuracy and a weighted F1-score of 0.9941; on the nine-site subset, the observed accuracy is 99.45% with zero missed defective cases. Balanced accuracy, specificity, missed-detection rate, false-alarm rate, and confidence intervals are additionally reported to better align the evaluation with engineering screening practice. The study also states the current limits of the evidence base, including partial soil annotation, dominant-soil simplification, restricted soil coverage, and the absence of leave-site-out and interpretability-focused validation. Overall, the results support soil-aware multimodal learning as a promising proof-of-concept direction for more context-aware automated LSPIT interpretation, while also identifying the validation steps still required for broad field deployment. Full article

Operando mechanical behavior of lithium-ion batteries under aggressive conditions remains insufficiently quantified, especially under combined high-rate and deep-discharge operation. This study investigated strain evolution in a commercial 18650 NMC lithium-ion cell using surface-mounted fiber Bragg grating sensors across 20 sequential conditions combining five discharge rates (1–4.5 C) and four cutoff voltages (2.5–1.0 V). All tests were performed on a single cell using identical 0.5 C constant-current constant-voltage charging, followed by a 2 h rest period and controlled discharge, to systematically evaluate mechanochemical evolution with increasing electrochemical severity. Maximum tensile strain during charging ranged from 45 to 59 µε and showed limited sensitivity to discharge severity. In contrast, discharge behavior exhibited clear rate- and cutoff-dependent transitions from tensile to compressive deformation; the most severe condition (4.5 C, 1.0 V cutoff) produced a peak compressive strain of about −27 µε and the most negative residual strain after relaxation. Although temperature increased monotonically with C-rate, strain evolution was nonlinear and non-monotonic, indicating that electrochemically induced stress dominated over thermal expansion alone. These findings reveal progressive amplification of irreversible deformation under severe discharge and demonstrate the value of fiber Bragg grating sensing for operando assessment of electrochemical–mechanical coupling in cylindrical lithium-ion cells. Full article

COVID-19 was a prolonged public-health shock that disrupted mobility, access to services, and household spending. Although the official U.S. poverty rate declined to 11.1%, the Supplemental Poverty Measure rose to 12.9%, suggesting that material hardship persisted unevenly across places. This study asks whether pre-existing livelihood vulnerability and local epidemic burden translated into geographically concentrated consumption losses during 2020–2022. Because sustained consumption loss can erode households’ health-related spending, tracking where spending declines concentrate helps connect local social and environmental conditions to how communities withstand a health crisis. We analyze consumer expenditure, unlike prior research relying on aggregate retail sales, to capture fine-grained economic strains as a proxy for shock-absorption capacity. A Livelihood Vulnerability Index (LVI) was calculated for each U.S. county using 16 socio-economic variables, and counties were classified as high- or low-risk. A multilevel model then examined how socio-economic and COVID-19 factors at county and census tract levels shaped consumption changes. Higher-risk communities experienced greater consumption reductions. At the census tract level, the non-White ratio, vacancy rate, built year, per capita income, education level, and housing value were significant. At the county level, COVID-19 cases and deaths, crowding, public transportation use, and vehicle availability mattered most. These findings support place-targeted strategies that combine public-health response with socio-environmental interventions to reduce disparities rooted in pre-existing vulnerability. Full article

Carbapenem-resistant Acinetobacter baumannii (CRAB) is classified as a critical priority pathogen by the World Health Organization, and new therapeutic alternatives are urgently needed. In this study, we performed genomic mining of 27,531 A. baumannii genomes and identified 5144 prophage-derived endolysin candidates. Four highly prevalent candidates (E1–E4) were recombinantly expressed and functionally evaluated against A. baumannii. Among them, E1 exhibited the strongest bactericidal activity against reference strains ATCC 19606 and CMCC 25001, with a minimum inhibitory concentration in the micromolar range. E1 effectively disrupted preformed biofilms (>60% reduction) and remained stable under a broad range of temperatures (4–60 °C), pH values (6–8), and NaCl concentrations (up to 500 mM). Structural analysis indicated that E1 adopts a canonical lysozyme-like fold with key residues for peptidoglycan binding, and its lytic activity in vitro relied on 1 mM EDTA-mediated outer membrane permeabilization. In a murine peritoneal infection model, combination therapy with E1 and meropenem (each at 1 × MIC) significantly increased the survival rate to 66.7% and reduced bacterial loads in blood and multiple organs. This study demonstrates that prophage-derived endolysin E1 acts synergistically with meropenem against A. baumannii, supporting E1 as a promising candidate for developing combination therapies against CRAB. Full article

The Zircaloy-4 alloy is a key structural material for nuclear reactor cores. However, its behavior under warm deformation conditions and during phase transformations requires in-depth investigation to improve technologies for producing ultrafine-grained (UFG) structures using severe plastic deformation methods. This work presents a comprehensive study of the rheological properties, phase stability, and microstructural evolution of the alloy in the temperature range from 20 to 950 °C at strain rates of 0.5 and 15 s⁻¹. The experimental part included plastometric testing, dilatometric analysis, and microstructural characterization. It was established that the optimal window for plastic deformation corresponds to warm deformation at 650 °C. Dilatometric analysis confirmed that heating to 650 °C ensures the preservation of a stable initial α-phase structure, since the formation of secondary phases and the α→β transformation are initiated at higher temperatures, namely 694 °C (onset) and 847 °C (completion). At 650 °C, the deformation resistance decreases by approximately 70% compared to cold processing, while the strain-rate sensitivity of the flow stress is minimized. EBSD analysis showed that deformation under these conditions leads to intensive grain fragmentation via mechanisms of dynamic recovery and the initial stages of continuous dynamic recrystallization. The decisive role of the kinetic factor was demonstrated: reducing the strain rate to 0.5 s⁻¹ promotes the formation of a finer and more homogeneous grain structure. In contrast, high strain-rate deformation (15 s⁻¹) results in coarser grains and increased non-relaxed intragranular residual stresses. The obtained results provide a physical basis for optimizing thermomechanical processing regimes and can be used to produce UFG structures in zirconium alloys without the risk of phase degradation. Full article

Accurately and promptly acquiring the load history characteristics of impact events on composite aircraft structures is crucial for identifying impact-induced damage and developing high-fidelity digital twin models. To address this need, we propose a method for reconstructing the impact load history on composite structures, leveraging Generalized Cross-Validation (GCV) and a Fiber Bragg Grating (FBG) pattern. An equivalent expansion technique based on discretized time-domain sparse strain sampling is developed to mitigate the local distortion of impact response signals, a common issue arising from the low sampling rates of quasi-distributed FBG. By incorporating Tikhonov regularization, the ill-posed nature of the impact frequency response matrix is effectively managed. Furthermore, an adaptive optimization method based on the GCV criterion is introduced to overcome the limitations of manually selecting regularization parameters and the associated constraints on noise suppression. The results show that the proposed GCV-based reconstruction method achieves an average peak relative error of 11.4% and an average root mean square error of 0.36 N for the reconstructed impact load, demonstrating that the proposed method synergistically enhances both the reconstruction of the overall impact load waveform profile and the precise characterization of transient details, even with low-rate sampling. This provides robust technical support for health monitoring and condition-based maintenance of composite structures. Full article