Search Results (815)

Agrobacterium tumefaciens, a destructive pathogen causing crown gall disease, results in substantial agricultural losses. Traditional chemical and existing biocontrol methods are limited by environmental pollution, pesticide resistance, and low efficacy, while bacteriophages emerge as a promising alternative due to their high host specificity, environmental compatibility, and low resistance risk. In this study, we isolated and characterized a lytic phage (PAT-A) targeting A. tumefaciens, evaluating its biological traits, genomic features, and biocontrol potential. The host strain A. tumefaciens CL-1 was isolated from cherry crown gall tissue and identified by 16S rDNA sequencing. Phage PAT-A was recovered from orchard soil via the double-layer agar method, showing a tadpole-shaped morphology (60 nm head diameter, 30 nm tail length) under transmission electron microscopy (TEM). Nucleic acid analysis confirmed a double-stranded DNA genome, susceptible to DNase I but resistant to RNase A and Mung Bean Nuclease. PAT-A exhibited an optimal MOI of 0.01, tolerated wide pH and temperature ranges, but was sensitive to UV (titer declined after 15 min of irradiation) and chloroform (8% survival at a 5% concentration). Whole-genome sequencing revealed a 44,828 bp genome with a compact structure, and phylogenetic/collinearity analyses placed it in the Atuphduvirus genus (Autographiviridae). Biocontrol experiments on tobacco plants demonstrated that PAT-A significantly reduced crown gall incidence. Specifically, simultaneous inoculation of PAT-A and A. tumefaciens CL-1 resulted in the lowest tumor incidence (12.0%), while pre-inoculation of PAT-A 2 days before pathogen exposure achieved an incidence rate of 33.3%. In conclusion, PAT-A is a novel strictly lytic phage with favorable biological properties and potent biocontrol efficacy against A. tumefaciens, enriching phage resources for crown gall management and supporting phage-based agricultural biocontrol strategies. Full article

Subsurface deposition determines whether soils, aquifers, or ocean sediment represent a sink or temporary reservoir for microplastics. Deposition is generally studied by applying the Smoluchowski–Levich equation to determine a particle’s sticking efficiency, which relates the number of particles filtered by sediment to the probability of attachment occurring from an interaction between particles and sediment. Sticking efficiency is typically measured using column experiments or estimated from theory using the Interaction Force Boundary Layer (IFBL) model. However, there is generally a large discrepancy (orders of magnitude) between the values predicted from IFBL theory and the experimental column measurements. One way to bridge this gap is to directly measure a microparticle’s interaction forces using Atomic Force Microscopy (AFM). Herein, an AFM method is presented to measure sticking efficiency for a model polystyrene microparticle (2 μm) on a model geomaterial surface (glass or quartz) in environmentally relevant, synthetic freshwaters of varying ionic strength (de-ionized water, soft water, hard water). These data, collected over nanometer length scales, are compared to sticking efficiencies determined through traditional approaches. Force measurement results show that AFM can detect extremely low sticking efficiencies, surpassing the sensitivity of column studies. These data also demonstrate that the 75th to 95th percentile, rather than the mean or median force values, provides a better approximation to values measured in model column experiments or field settings. This variability of the methods provides insight into the fundamental mechanics of microplastic deposition and suggests AFM is isolating the physicochemical interactions, while column experiments also include physical interactions like straining. Advantages of AFM over traditional column/field experiments include high throughput, small volumes, and speed of data collection. For example, at a ramp rate of 1 Hz, 60 sticking efficiency measurements could be made in only a minute. Compared to column or field experiments, the AFM requires much less liquid (μL volume) making it effortless to examine the impact of solution chemistry (temperature, pH, ionic strength, valency of dissolved ions, presence of organics, etc.). Potential limitations of this AFM approach are presented alongside possible solutions (e.g., baseline correction, numerical integration). If these challenges are successfully addressed, then AFM would provide a completely new approach to help elucidate which subsurface minerals represent a sink or temporary storage site for microparticles on their journey from terrestrial to oceanic environments. Full article

Chicken respiratory diseases represent multifactorial conditions resulting from viral, bacterial, mycoplasmal pathogens, and environmental factors, causing significant economic losses within the poultry industry. A specific respiratory disease characterized by breathing difficulties and bronchial occlusion due to caseous exudates is termed chicken bronchial obstruction. However, the absence of rapid, precise, and highly sensitive diagnostic methods for differentiation of primary respiratory disease pathogens or opportunistic pathogens, including avian influenza virus (AIV), infectious bronchitis virus (IBV), Pseudomonas aeruginosa (P. aeruginosa), and Escherichia coli (E. coli), constitutes a substantial challenge. This study developed a quadruplex droplet digital polymerase chain reaction (ddPCR) method that targeted the HA gene of H9 subtype AIV, the M gene of IBV, the Pal gene of P. aeruginosa, and the UidA gene of E. coli. Following the optimization of annealing temperature, sensitivity, and repeatability, the minimum detectable concentrations were determined as 3.02 copies/μL for the HA gene of H9 subtype AIV, 3.08 copies/μL for the M gene of IBV, 3.19 copies/μL for the Pal gene of P. aeruginosa, 3.39 copies/μL for the UidA gene of E. coli. No cross-reactivity was observed with Newcastle disease virus (NDV), H5 subtype AIV, H7 subtype AIV, fowl adenovirus serotype 4 (FAdV-4), infectious laryngotracheitis virus (ILTV), Avibacterium paragallinarum, Streptococcus, Salmonella, Pasteurella multocida, and Staphylococcus aureus. The method demonstrated excellent repeatability, with a coefficient of variation (CV) below 9%. The 185 clinical samples collected in Hebei Province China are tested by both quadruplex ddPCR and quadruplex qPCR method and the results compared. The sensitivity of the quadruplex ddPCR method (57.30%; 106/185) slightly exceeded that of the quadruplex qPCR method (49.73%; 92/185). Pathogens or opportunistic pathogens positive rates obtained via the quadruplex ddPCR were 40.00% for H9 subtype AIV, 33.51% for IBV, 24.32% for P. aeruginosa, and 27.57% for E. coli. In comparison, the positive rates of H9 subtypes AIV, IBV, P. aeruginosa, and E. coli from the quadruplex qPCR were 36.22%, 30.81%, 21.62%, and 24.32%, respectively. The coincidence rates between the two methods were 96.22% for H9 AIV, 97.30% for IBV, 97.30% for P. aeruginosa, and 96.76% for E. coli. These results demonstrated that the quadruplex ddPCR method represented a highly sensitive, specific, and rapid technique for identifying H9 subtype AIV, IBV, P. aeruginosa, and E. coli. Full article

Examining the long-term spatiotemporal distribution of grassland types and their transitions is crucial for better understanding regional and global changes. Most research in this field has examined the spatial distribution, temporal dynamics of grasslands, and their causes as a unified entity. This study predicted the distribution of nine major grassland types in Xinjiang under three climate change scenarios from 2041 to 2100 based on 1980s grassland maps, field data in 2023, and 28 factors. The total area of the nine grassland types showed a decreasing trend from 2041 to 2100. The lowland meadow (LM), temperate meadow steppe (TMS), temperate steppe desert (TSD), temperate desert steppe (TDS), and mountain meadow (MM) expanded, while significant declines occurred in alpine meadow (AM), alpine steppe (AS), temperate desert (TD), and temperate steppe (TS). Among cumulative contribution rate of the 28 factors examined in this study, NDVI, vegetation type, slope, elevation, soil_symbol, soil_ph, Bio1, Bio5, Bio8, Bio9, Bio10, Bio12, Bio13, Bio15, and Bio18 played important roles in most grassland types. LM, TD, and AS grassland were found to be more sensitive to E (environment), while AM, TDS, and TSD were more influenced by T (temperature). The distributions of MM and TMS are significantly influenced by the combined effects of all three categories of factors. For TS, the impacts of both temperature and environmental factors are substantial. These findings provided a robust foundation for conservation planning and the sustainable management of grassland ecosystems in temperate and alpine regions. Full article

Pseudomonas extremorientalis PEY1, isolated from the intestinal contents of marine fish, was evaluated for the production and properties of antibacterial proteins active against Edwardsiella tarda, a major pathogen in aquaculture. Antibacterial production was maximized in a minimal medium supplemented with 1% yeast extract and 1% galactose under stationary cultivation at 25 °C and pH 7.0. Growth and bioactivity assays were conducted under varying carbon and nitrogen sources, temperatures, and pH levels. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis revealed a distinct ~37 kDa protein band corresponding to antibacterial activity, exhibiting an inhibition zone of 2.4 ± 0.1 cm against E. tarda. The activity was completely abolished by papain digestion but remained detectable after exposure to 55 °C and pH 8, indicating that the active compound is a moderately heat-stable, proteinaceous antibacterial molecule. LC–MS/MS analysis identified the protein as a putative disulfide reductase with ~40% sequence coverage. The antibacterial factor exhibited strong physicochemical stability, retaining activity in the presence of surfactants and metal ions. Collectively, these findings demonstrate that P. extremorientalis PEY1 produces a thermostable, papain-sensitive antibacterial protein with selective activity against E. tarda, highlighting its potential as a promising natural biocontrol or postbiotic candidate for sustainable aquaculture. Full article

In the bioprocessing industry, real-time monitoring of bioreactors is essential to ensuring product quality and process efficiency. Conventional monitoring methods can satisfy some needs but suffer from calibration drift, limited spatial coverage, and incompatibility with harsh or miniaturized environments. Optical fiber sensors, with their high sensitivity, remote monitoring capability, compact size, and multiplexing, have become a promising technology for in situ bioreactor monitoring. This review summarizes recent progress in optical fiber sensors for key bioreactor parameters, with an emphasis on pH and dissolved oxygen (DO), and briefly covers temperature and pressure monitoring. Different sensing mechanisms, materials, and fiber architectures are compared in terms of sensitivity, response time, stability, and integration strategies in laboratory and industrial-scale bioreactors. Finally, current challenges and future trends are discussed, including multi-parameter sensing, long-term reliability, and the integration of optical fiber sensors with process analytical technology and data-driven control for intelligent bioprocessing. Full article

Octachlorinated metal phthalocyanines (MPcCl₈, M = Co, Zn, VO) represent an underexplored class of functional materials with promising potential for chemiresistive sensing applications. This work is the first to determine the structure of single crystals of CoPcCl₈, revealing a triclinic (P-1) packing motif with cofacial molecular stacks and an interplanar distance of 3.381 Å. Powder XRD, vibrational spectroscopy, and elemental analysis confirm phase purity and isostructurality between CoPcCl₈ and ZnPcCl₈, while VOPcCl₈ adopts a tetragonal arrangement similar to its tetrachlorinated analogue. Thin films were fabricated via physical vapor deposition (PVD) and spin-coating (SC), with SC yielding highly crystalline films and PVD resulting in poorly crystalline or amorphous layers. Electrical measurements demonstrate that SC films exhibit n-type semiconducting behavior with conductivities 2–3 orders of magnitude higher than PVD films. Density functional theory (DFT) calculations corroborate the experimental findings, predicting band gaps of 1.19 eV (Co), 1.11 eV (Zn), and 0.78 eV (VO), with Fermi levels positioned near the conduction band, which is consistent with n-type character. Chemiresistive sensing tests reveal that SC-deposited MPcCl₈ films respond reversibly and selectively to ammonia (NH₃) and hydrogen sulfide (H₂S) at room temperature. ZnPcCl₈ shows the highest NH₃ response (45.3% to 10 ppm), while CoPcCl₈ exhibits superior sensitivity to H₂S (LOD = 0.3 ppm). These results suggest that the films of octachlorinated phthalocyanines produced by the SC method are highly sensitive materials for gas sensors designed to detect toxic and corrosive gases. Full article

In this study, nine different Propionibacterium freudenreichii strains were isolated from Kars Gravyer produced by traditional methods in Turkey and identified by sequencing the 16S–23S intergenic region using species-specific primers. The isolated strains were examined in vitro for the presence of the β-galactosidase enzyme, autoaggregation ability, sensitivity against eight selected antibiotics and survivability under harsh conditions in order to determine their potential probiotic properties. After probiotic potentials were evaluated, an experimental design was made to optimize the production of vitamin B12 in a 3 L glass bioreactor P. freudenreichii NUV774. While all strains showed similar resistance (92–98%) to gastric juice (0.3% pepsin, pH 3.0), they showed resistance to intestinal fluid (0.1% pancreatin, 0.3% bile salt, pH 8.0) between 60% and 92%. It was determined that the viability after 3 and 6 h of incubation in 0.5% and 1% bile salt differed between strains. All isolates exhibited resistance to ciprofloxacin, ampicillin, and trimethoprim–sulphamethoxazole; however, most were sensitive to ofloxacin. Overall, P. freudenreichii strains showed resistance to the gastrointestinal tract, tolerance to pH 3.0, and high tolerance to bile salts. As a result of optimization, maximum vitamin B12 production was found to be 156.8 mg/L. The optimum operating conditions were calculated as temperature = 36.9 °C, aeration = 2.430 vvm, and agitation = 159.120 rpm. Hence, P. freudenreichii, as future probiotic strain candidates, will offer an alternative source to Lactobacillus, Bifidobacterium and some Bacillus spp. In addition, this study denoted that the alteration of the production of active vitamin B12 by P. freudenreichii occurs in a strain-dependent manner. Full article

Aeschynomene indica L. has become a problematic weed in the upland direct-seeding rice fields of the lower Yangtze River region, China, leading to substantial yield reductions. A comprehensive understanding of its seed germination ecology and response to herbicides is crucial for developing effective control strategies. This study examined the effects of major environmental factors including temperature, light, pH, salt stress, osmotic potential, and burial depth on seed germination of A. indica and assessed the efficacy of 20 commonly used herbicides in rice under controlled conditions. Results revealed that germination was highly sensitive to temperature, with optimum constant and alternating temperatures of 35 °C and 40/30 °C (day/night), respectively, both achieving germination rates above 90%. The seeds were non-photoblastic, maintaining a high germination rate of 83.33% under complete darkness. Germination remained consistently high across a broad pH range from 4 to 9, with rates ranging from 83.33% to 96.67%. Salt and osmotic stresses markedly suppressed germination, with EC₅₀ values of 195.08 mmol·L⁻¹ NaCl and −0.43 MPa, respectively. Seedling emergence decreased significantly with increasing burial depth, with no emergence occurring at depths greater than 7 cm. The EC₅₀ for emergence was 4.21 cm. Among the herbicides screened, saflufenacil and mesotrione were the most effective pre-emergence treatments, with GR₅₀ values of 5.38 and 12.02 g ai ha⁻¹, respectively. Florpyrauxifen-benzyl and fluroxypyr-meptyl exhibited the highest post-emergence activity, with GR₅₀ values of 0.20 and 19.69 g ai ha⁻¹, respectively. These results underscore the high ecological adaptability of A. indica to paddy fields conditions and provide a scientific foundation for integrating chemical control with cultural practices such as deep tillage into sustainable weed management systems for paddy fields. Full article

Biocompatible stimuli-sensitive hydrogels are a versatile and promising class of materials with significant potential for various biomedical applications. These ‘’smart’’ hydrogels can dynamically respond to external environmental stimuli such as pH, temperature, enzymes, or biomolecular interactions, enabling controlled drug release, tissue regeneration, wound healing, and biosensing applications. Hydrogels derived from natural polymers, including chitosan, alginate, collagen, and hyaluronic acid, offer key advantages such as intrinsic biocompatibility, biodegradability, and the ability to mimic the extracellular matrix. Their ability to respond to environmental stimuli—including pH, temperature, redox potential, and enzymatic activity—enables control over drug release and tissue regeneration processes. This review explores the fundamental principles governing the design, properties, and mechanisms of responsiveness of natural stimuli-sensitive hydrogels. It also highlights recent advancements in their biomedical applications, discusses existing challenges, and outlines future research directions aimed at improving their functional performance and therapeutic potential for sustainable healthcare solutions. Full article

Reforestation efforts, notably the massive Grain for Green Project (GFGP), have significantly greened China’s Loess Plateau (LP) but intensified regional water limitations. This study aims to systematically characterize the spatio-temporal dynamics and the critical legacy effects of moisture stress on eWUE to evaluate ecosystem sustainability under accelerated climate change. Using 2001–2020 MODIS GPP and ET data and the comprehensive Temperature–Vegetation–Precipitation Drought Index (TVPDI), we analyzed the trends, spatial patterns, and lagged correlations on the LP. We find the LP’s mean eWUE was 1.302 g C kg⁻¹ H₂O, exhibiting a robust increasing trend of 0.001 g C kg⁻¹ H₂O a⁻¹ (p < 0.05), primarily driven by a faster increase in gross primary productivity (GPP) than evapotranspiration (ET). Spatially, areas with significant increases in eWUE concentrated in the afforested south and central LP. Concurrently, the region experienced a mild drought state (mean TVPDI: 0.557) with a concerning drying trend of 0.003 yeyr⁻¹, highlighting persistent water stress. Crucially, eWUE exhibited high and spatially divergent sensitivity to drought. A striking 69.64% of the region showed a positive correlation between eWUE and the TVPDI, suggesting that vegetation may adjust its physiological functions to adapt to drought. However, this correlation varied across vegetation types, with grasslands showing the highest positive correlation (0.415) while woody vegetation types largely showed a negative correlation. Most importantly, our analysis reveals a pronounced drought legacy effect: the correlation between eWUE and drought in the previous two years was stronger than in the current year, indicating multi-year cumulative moisture deficit rather than immediate climatic forcing (precipitation and temperature). These findings offer a critical scientific foundation for optimizing water resource management and developing resilient “right tree, right place” ecological restoration strategies on the LP, mitigating the ecological risks posed by prolonged drought legacy. Full article

High-speed running (HSR) has the greatest physiological impact on soccer players. It is closely linked to neuromuscular fatigue and muscle damage post-match, emphasizing the role that load monitoring plays in both performance and recovery. The aim of this study was to examine the relationship between match locomotor demands and the relative change in skin temperature (%ΔT) following official matches. A professional soccer team was analyzed during 14 regular-season matches. Infrared thermography (IRT) assessments were conducted before the match and up to 36 h after the match. The analyzed regions included posterior protocols of the lower limb. The kinematic variables of the match were obtained through a GPS device. Players were classified into high- and low-load groups based on the median values of HSR distance (372 m) and total distance (9675 m). Linear mixed-effects models showed that players in the high HSR group (≥372 m) demonstrated greater post-match decreases in %ΔT, particularly in the hamstring region (β = −1.79 ± 0.54 °C, 95% CI: −2.87 to −0.72, p = 0.001, R² = 0.18), with a moderate-to-large effect size (ES = 0.67). Total distance also explained temperature change in the hamstrings (β = −1.46 ± 0.73 °C, p = 0.04). These findings suggest that post-match skin temperature reduction is sensitive to high-intensity running exposure, supporting IRT as a complementary internal load monitoring tool. Full article

Bioactive compounds are widely recognized for their ability to enhance health and prevent diseases due to their various biological activities. However, these compounds are very sensitive to environmental factors, which can reduce their solubility, bioavailability, permeability, and stability, necessitating carriers to protect and ensure targeted delivery. To develop an effective delivery system, it is essential to assess the key factors that influence the release behaviour of bioactive compounds. Therefore, the primary aim of this study is to evaluate how the conditions of the release media, the attributes of hydrogels, and the characteristics of the entrapped bioactive compounds regulate the release kinetics of these compounds. Prior to create suitable carriers, it is essential to comprehend the mechanisms of digestion and absorption of these compounds. Consequently, absorption and the factors influencing stability and bioavailability of bioactives were reviewed first. The conditions of release media, especially the pH, ionic characteristics, temperature, and the nature of solvent served as a critical determinant in the release of bioactive substances by affecting the functional groups, electrostatic interactions between carrier and entrapped bioactive compound, dissociation and conformational changes in polymers. The properties of delivery systems can be controlled using polymers, crosslinkers, plasticizers, and specific environmental factors. The application of dual crosslinkers or a combination of physical and chemical crosslinkers enhanced the efficiency of the crosslinking process, subsequently improving the overall release profile of bioactive compounds from the matrices. Therefore, this review explored several options for enhancing the delivery system. Full article

Aeromonas hydrophila is a typical pathogen that causes fish diseases and can easily infect different fish species. This study investigated the antibacterial activity, physicochemical properties and antibacterial mechanism of the BLIS UI-11 produced by Lactobacillus plantarum HYH-11, isolated from traditional kimchi in Hebei, China. It was found that BLIS UI-11 showed excellent inhibitory effect on the growth of A. hydrophila, and it also had a good antibacterial effect on various pathogens such as Vagococcus fluvialis, Listeria monocytogenes, Aeromonas dhakensis, Aeromonas salmonicida, Salmonella Typhimurium, Escherichia coli and Staphylococcus aureus. By measuring growth kinetics, it was found that the maximum antibacterial activity was reached after 30 h of culture, and both the optical density value at 600 nm (OD₆₀₀₎ and pH basically entered the stable phase after 20 h. Whole-genome analysis and gene cluster prediction identified a RiPP-like biosynthetic gene cluster, which comprises genes encoding precursor peptides, modification enzymes, and transport/immunity components. The molecular weight of the antimicrobial active substance was detected by dialysis and Tricine-SDS-PAGE, and it was shown to be an ultra-small molecular substance (<1 kDa). BLIS UI-11 was sensitive to protease K, but its antibacterial activity remained stable after treatment with acidic environment (pH 3.0–6.0), high-temperature treatment (121 °C for 30 min), and ultraviolet irradiation (4 h). After the sub-live cell assay (PI/SYTO9) and scanning electron microscopy (SEM), BLIS UI-11 inhibited the growth of bacteria by destroying the cell membrane of A. hydrophila to deform, collapse, and form holes that lead to accounting leakage. The hemolysis assay indicated that BLIS UI-11 exhibited incomplete hemolysis, suggesting its safety for application. The results showed that BLIS UI-11 produced by strain HYH-11 has great potential as an antimicrobial agent against A. hydrophila infection. Full article

Real-time, in situ soil diagnostics are increasingly relevant for precision agriculture, but their efficacy under varying field and climatic conditions remains underexplored. This study assesses the 2022/23 version of the Stenon FarmLab, a multi-sensor soil analysis tool, over a 10-month period and across 1187 measurements on six fields (five cropped, one grassland) in northeast Germany. Despite the common approach of comparing a field sensor against lab results, in this paper, the FarmLab’s outputs are benchmarked using various approaches, such as time series, correlation, and geostatistical analysis, to fully evaluate the temporal and spatial stability and alignment with known soil heterogeneity. While physical soil parameters such as temperature and soil texture showed robust detection accuracy, key agronomic metrics—including mineral nitrogen (Nmin), soil organic carbon (SOC), and phosphorus—exhibited poor temporal consistency and low correlation with expected spatial patterns. Measurement errors and high sensitivity to weather conditions restrict data quality, particularly under frost and drought. Spatial clustering of more temporally stable parameters (e.g., pH, soil texture) allowed for limited zone delineation. We conclude that while the FarmLab shows partial potential for on-site soil sensing, significant limitations in nutrient measurement reliability currently prevent its use in operational precision agriculture. Enhancements in sensor calibration, environmental compensation, and software are needed for broader applicability. Full article