Search Results (2,748)

Three Ir(III) complexes 1–3 were synthesized using phenyl-modified 2-phenylpyridine derivatives as the cyclometalating ligands. All complexes exhibited aggregation-induced phosphorescence emission (AIPE) in CH₃CN/H₂O, which facilitated highly sensitive detection of 2,4,6-trinitrophenol (TNP). Among them, complex 3 containing a phenyl group at the para-position of the phenyl moiety in 2-phenylpyridine showed superior detection performance with the limit of detection (LOD) of 74 nM. 1–3 demonstrated excellent anti-interference and selectivity performances for the detection of TNP in different common water samples. In addition, ¹H NMR spectra, density functional theory calculations, and spectroscopic results indicate that the detection mechanism for TNP is attributed to the combined effects of photo-induced electron transfer and the inner-filter effect. Full article

Enterprise document management faces a significant challenge: traditional clustering methods focus solely on content similarity while ignoring organizational context, such as priority, workflow status, and temporal relevance. This paper introduces FLACON (Flag-Aware Context-sensitive Clustering), an information-theoretic approach that captures multi-dimensional document context through a six-dimensional flag system encompassing Type, Domain, Priority, Status, Relationship, and Temporal dimensions. FLACON formalizes document clustering as an entropy minimization problem, where the objective is to group documents with similar contextual characteristics. The approach combines a composite distance function—integrating semantic content, contextual flags, and temporal factors—with adaptive hierarchical clustering and efficient incremental updates. This design addresses key limitations of existing solutions, including context-aware systems that lack domain-specific intelligence and LLM-based methods that require prohibitive computational resources. Evaluation across nine dataset variations demonstrates notable improvements over traditional methods, including a 7.8-fold improvement in clustering quality (Silhouette Score: 0.311 vs. 0.040) and performance comparable to GPT-4 (89% of quality) while being ~7× faster (60 s vs. 420 s for 10 K documents). FLACON achieves $O\left(mlogn\right)$ complexity for incremental updates affecting $m$ documents and provides deterministic behavior, which is suitable for compliance requirements. Consistent performance across business emails, technical discussions, and financial news confirms the practical viability of this approach for large-scale enterprise document organization. Full article

Escherichia coli O157:H7 (EcO157) is a Gram-negative foodborne pathogen capable of transmitting between soil, food, and humans, posing a threat to human health. The soil pH in Jilin Province decreases gradually from west to east, exhibiting a natural pH gradient zone. Persistence of EcO157 in soils from different places was widely reported, while its survival behavior in soils over a pH gradient is yet to be investigated. In the current study, a total of 24 soil samples were collected along a natural pH gradient. Soils were classified into weak acidic soil (pH < 6.5), neutral soil (6.5 < pH < 7.5), weak basic soil (7.5 < pH < 8.5), and strong basic soil (8.5 < pH < 10). EcO157 cells were inoculated into those soils and the survival profiles were investigated. The influencing factors affecting the survival behavior of EcO157 were analyzed by multivariate statistical analysis. The results showed that the average survival time of EcO157 in weak acidic, neutral, weak basic, and strong basic soils was 61.08, 72.05, 76.85, and 18.54 days, respectively. The survival time in strong basic soils was significantly less than that in the other three soil groups. Soil physicochemical properties such as NO₃⁻-N and NH₄⁺-N were negatively linked to the survival of EcO157, while total phosphorus (TP)was positively correlated to the survival of EcO157 (p < 0.05). The microbial community α diversity index was negatively correlated with the survival of EcO157, while relative abundance of Proteobacteria and Acidobacteria was positively and negatively correlated to the survival of EcO157, respectively. Both co-occurrence network analysis and structural equation model results showed that pH was a key factor that could directly and indirectly influence the survival of EcO157 via the bacterial community. Our data coupled with the findings of other studies might be of great help in the evaluation, control, and reduction of the potential health risk associated with EcO157 in soils along a natural pH gradient. Full article

Background: Endometrioma recurrence after laparoscopic cystectomy remains a clinical challenge in the long-term management of endometriosis. The Empressin Injection Technique (EIT), which involves the use of a vasopressin analog during surgery, may reduce recurrence by improving the completeness of cyst removal. This study aimed to evaluate the impact of the EIT on recurrence rates compared to standard cystectomy without Empressin. Methods: We conducted a retrospective case–control study of 263 patients who underwent laparoscopic cystectomy for unilateral or bilateral endometriomas between 2014 and 2024 at a tertiary endometriosis referral center. The patients were divided into two groups: EIT (n = 110) and control (n = 153). In the EIT group, 10 mL of diluted Empressin (1 mL in 100 mL NaCl 0.9%) was injected at the cyst capsule–ovarian cortex interface prior to stripping. Demographic and clinical variables were analyzed using descriptive statistics (chi-square test and the Mann–Whitney t-test) and logistic regression to identify factors associated with recurrence between the two groups. Results: No significant differences were found between the groups regarding age, BMI, #ENZIAN O score, or r-ASRM stage. No intraoperative or postoperative complications were reported. Recurrence was significantly lower in the EIT group (5.5%) compared to the control group (19.6%) (p = 0.001; OR 0.2, 95% CI: 0.08–0.55). Hormonal therapy was administered postoperatively in 69.1% of EIT patients and 62.5% of controls. Pregnancy rates were comparable between the groups. Repeat surgery for recurrence was required only in the control group (4.2%, p = 0.004). Conclusions: Use of Empressin during laparoscopic cystectomy significantly reduces endometrioma recurrence without adverse effects, particularly when combined with postoperative hormonal therapy. Full article

Background/Objectives: Pharmaceutical cocrystallization offers a promising strategy to enhance drug properties while preserving molecular integrity. Ezetimibe, a BCS Class II hypolipidemic agent, faces therapeutic limitations due to poor aqueous solubility. This study aimed to systematically evaluate cocrystallization of ezetimibe with organic acid (benzoic, tartaric, or succinic acid) at varying stoichiometric ratios (1:0.5–1:2) to optimize physicochemical properties and oral bioavailability. Methods: Cocrystals were prepared via solvent evaporation (SEV) and solvent/anti-solvent (SAS) methods. Structural characterization included Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and powder/single-crystal X-ray diffraction (PXRD/SCXRD). Physicochemical performance was assessed through saturation solubility, in vitro dissolution, and in vivo pharmacokinetics in male Sprague Dawley rats (n = 4/group). Results: Benzoic acid cocrystals (1:2 ratio, SEV) showed O−H⋯N hydrogen bonding (FTIR band shifts: 2928 → 3264 cm⁻¹) and novel crystalline phases (12.4°, 16.7°, and 24.9°). SCXRD confirmed monoclinic P2₁/n symmetry (a = 5.42 Å, b = 5.05 Å) for benzoic acid cocrystals. Ezetimibe/benzoic acid cocrystals (1:2) achieved 64-fold solubility enhancement and 2× faster dissolution vs. pure ezetimibe. Pharmacokinetics revealed 3× higher Cmax (18.38 ng/mL) and 4× greater AUC (40.36 h·ng/mL) for optimized cocrystals. Tartaric and succinic acid cocrystals showed moderate improvements, with melting points intermediate between parent compounds. Conclusions: Both stoichiometry and preparation method strongly determined cocrystal performance. Benzoic acid at a 1:2 ratio via SEV demonstrated superior solubility, dissolution, and bioavailability, addressing ezetimibe’s formulation challenges. These findings underscore the potential of rational cocrystal design to overcome solubility barriers in oral dosage development, particularly for hydrophobic therapeutics. Full article

Schwertmannite (Fe₈O₈(OH)_8−2x(SO₄)_x), an iron oxyhydroxysulfate mineral prevalent in acidic mining environments, demonstrates exceptional heavy metal adsorption capacity owing to its high surface area and abundant functional groups. This study developed a novel one-step synthesis method that simultaneously generates schwertmannite and removes Pb²⁺ from aqueous solutions, contrasting with conventional two-step approaches. Systematic investigation of operational parameters revealed that Pb²⁺ removal efficiency exceeded 98% across concentrations of 0~300 mg·L⁻¹, with optimal performance at n_Sch:n_Pb ratios ≥ 2, pH 3.0~6.0, and 35 °C. Characterization studies identified four primary removal mechanisms: electrostatic adsorption, ion exchange, coordination complexation, and coprecipitation. The in situ method demonstrated significant advantages in processing efficiency, removal stability, and environmental sustainability compared to traditional approaches. Full article

Background: There is inadequate evidence to support recommendations for the delayed clamping of umbilical cords in preterm neonates who are born non-vigorous. Objective: In a preterm bradycardic ovine model, our objective was to compare the effects of early cord clamping with ventilation (ECCV) and various time periods of delayed cord clamping with ventilation (DCCV) at 1 min (DCCV1), 2 min (DCCV2), 3 min (DCCV3), 4 min (DCCV4), and 5 min (DCCV5). The primary composite outcome was (i) incidence of achieving a combined heart rate (HR) ≥ 100 bpm and preductal saturation (SpO₂) ≥80% by 5 min, and (ii) time to attain this outcome. Secondary outcomes were to evaluate gas exchange/hemodynamics. Methods: 32 preterm lambs of 126–128-day gestational age were randomized to one of six groups: ECCV (n = 5), DCCV1 (n = 6), DCCV2 (n = 5), DCCV3 (n = 6), DCCV4 (n = 6), and DCCV5 (n = 4). Asphyxia was induced by umbilical cord occlusion to attain a HR ≤ 90 beats per minute (bpm). Results: All lambs in DCCV5 achieved a primary composite outcome by 5 min. The time taken to achieve the primary composite outcome in DCCV5 was significantly lower (p = 0.02). Partial pressure of arterial carbon dioxide (PaCO₂) was significantly lower (p = 0.0001) in DCCV5. Peak pulmonary blood flow (PBF) was significantly higher (p = 0.0001) in DCCV5 while peak carotid blood flow (CBF) was highest in the ECCV (p < 0.0001) compared to other groups. Conclusions: In a preterm ovine model of asphyxia, resuscitation with an intact umbilical cord for 5 min increased the incidence and reduced the time to achieve the primary composite outcome, while also improving gas exchange by enhancing pulmonary blood flow, compared to shorter durations of DCCV and ECCV. These findings suggest that DCCV for 5 min may offer physiological advantages in the resuscitation of non-vigorous preterm neonates, warranting further investigation in clinical settings. Full article

Background/Objectives: Preoxygenation with 100% oxygen is commonly used but poses risks such as hyperoxia and atelectasis. Using 80% oxygen may reduce these effects but shortens duration of apnoea without desaturation (DAWD). This study compared preoxygenation efficiency between 80% and 100% oxygen and evaluated changes in the Oxygen Reserve Index™ (ORi™). Methods: Patients undergoing elective laparoscopic cholecystectomy were randomized to preoxygenation with 80% or 100% oxygen. Adequate preoxygenation was defined as a ≤10% difference between fraction of inspired oxygen and end-tidal oxygen (EtCO₂). The primary outcome was DAWD, the interval from apnoea onset to peripheral oxygen saturation (SpO₂) of 93%. Secondary outcomes included time to adequate preoxygenation and additional warning time from ORi™ zero to SpO₂ 97%. Results: Thirty patients were randomised to 80% (n = 15) or 100% oxygen (n = 15) oxygen groups. One patient in the 100% group was excluded due to spontaneous breathing before SpO₂ 93%, leaving 29 for DAWD analysis. DAWD was 345 ± 136 s (80%) and 430 ± 163 s (100%) with a mean difference of 86 s (p = 0.135). No significant differences were observed in tie to adequate preoxygenation or additional warning time. Conclusions: Preoxygenation with 80% oxygen resulted in a numerically shorter DAWD compared with 100% oxygen, without a significant difference in ORi™. These findings may suggest the potential feasibility of using 80% oxygen for preoxygenation. However, given the limited sample size and uncertain clinical relevance, further large-scale studies are warranted to clarify the safety and clinical implications of lower oxygen concentration during anaesthesia induction. Full article

Nitroguanidine-type energetic materials have broad application prospects in the propellant field, and their derivative structures are numerous, with intricate changes in macro-level properties. However, due to the unclear inherent evolution mechanisms of these macro-level properties, the structural optimization of compounds and the iteration of application systems face difficulties. This work systematically investigates the variations in density, thermal decomposition, and sensitivity among nitroguanidine (NQ), 1-amino-2-nitroguanidine (ANQ), and 1-amino-2-nitroguanidinium nitrate (ANGN). Hirshfeld surface and bond dissociation energy analyses reveal that strengthened electrostatic and inductive interactions enhance the hydrogen bonding network in ANGN, leading to its higher density compared to NQ. In contrast, weakened electrostatic interactions in ANQ result in a less robust hydrogen bonding network and a correspondingly lower density. The sensitivity trend is consistently explained from both molecular and crystalline perspectives: an increasingly inhomogeneous electrostatic potential distribution, coupled with a higher frequency of O···O contacts, provides a coherent explanation for the experimental observations. Furthermore, the electron-withdrawing -NH₃⁺ group in ANGN weakens the N–NO₂ bond, reducing its bond dissociation energy and leading to the most intense NO₂ mass spectral signal during thermal decomposition. ANQ exhibits the opposite behavior. A linear correlation (R² = 0.92) is observed between the N–NO₂ BDE and NO₂ mass spectral intensity across NQ, ANQ, and ANGN. This study provides unique insights into the intrinsic mechanisms governing variations in the properties of nitroguanidine derivatives. Full article

Nutrient losses through leaching and low nutrient use efficiency are major challenges limiting crop productivity and causing environmental pollution. Biochar has been widely studied as a soil amendment to improve nutrient retention; however, the combined effects of pyrolysis temperature and post-production oxidation on soil nutrient dynamics and plant performance remain unclear. In this study, wheat straw and wood residue biochars were produced at two pyrolysis temperatures (350 and 450 °C) and subsequently modified by hydrogen peroxide (H₂O₂) oxidation to enhance surface functionality. A pot experiment with fava bean (Vicia faba L.) was conducted to evaluate the effects of pristine and oxidized biochars on soil chemical properties, nutrient leaching, and plant nutrient uptake. Results showed that pristine biochars increased soil pH from 6.82 (control) to 8.73–9.12 and EC from 2.15 to 3.06–4.71 dS m⁻¹, with wheat straw biochars having stronger alkalizing effects. In contrast, oxidized biochars decreased soil pH to 5.62–5.93 due to the introduction of oxygen-containing functional groups. All biochars reduced NO₃⁻-N, NH₄⁺-N, and PO₄³⁻-P leaching, with the most pronounced reductions observed in oxidized wheat straw biochar produced at 450 °C (O-BWS₄₅₀). Improved nutrient retention translated into higher plant nutrient uptake: fava bean plants grown in O-BWS₄₅₀-amended soil achieved the greatest N (6.71%) and P (3.89%) uptake, significantly higher than the control. These findings highlight the potential of oxidation-modified biochars, particularly wheat straw biochar produced at moderate pyrolysis temperature, to improve soil nutrient conservation and enhance crop nutrition simultaneously. Such modifications represent a promising approach for developing biochar-based soil amendments that promote sustainable nutrient management. Full article

The widespread use of recycled fine aggregate (RFA) is hindered by its porous and weak adhered mortar. In this study, a nano-SiO₂–sodium silicate mixed solution (NMS) was used to soak and strengthen the adhered mortar. Alkali-activated slag was adopted as the cementitious material, and the resulting treated waste liquid (RNMS) was recycled as a sodium silicate source for the alkali activator. The effects of modified RFA (MRFA) incorporation and RNMS use on the performance, economic, and environmental benefits of alkali-activated slag recycled fine aggregate mortar (AASRM) were evaluated. Compared with the control group, mortars using only MRFA showed significantly improved performance, with a 28-day compressive strength increase of 57.6% (reaching 38.3 MPa) and enhanced workability. The capillary water absorption and 90-day drying shrinkage rates decreased by 49.5% and 40.2%, respectively. Microstructural analysis revealed that NMS treatment promoted the formation of additional C-(N)-A-S-H gel, thereby densifying the surface of the RFA and strengthening the interfacial transition zone (ITZ). More importantly, using RNMS as the alkali activator source maintained the excellent performance of the AASRM mortar, with the compressive strength reaching 95.6% of that prepared with a fresh alkali activator, while effectively reducing material costs and embodied carbon. This study not only successfully applies MRFA in alkali-activated mortar systems but also provides an effective approach for the in situ recycling of treated waste liquid. Full article

The bloom of cyanobacteria has severely disrupted ecological balances, posing significant risks to human health and safety. However, there is currently a lack of environmentally friendly methods that can sustainably suppress these blooms over the long term. This study integrates untargeted metabolomics, Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) to systematically characterize the responses of Microcystis aeruginosa to nano zero-valent iron (nZVI). Exposure to nZVI reprograms lipid and amino acid metabolism, coincides with the suppression of protein biosynthesis, and perturbs central pathways—including the tricarboxylic acid (TCA) cycle, photosynthesis, and carbohydrate metabolism—leading to disruptions in energy balance and metabolic homeostasis. FTIR and SEM provide complementary evidence of membrane compromise, with attenuation of -OH, -C-H, and C=O functional group signals, abnormal cell morphology, and progressive oxidative injury culminating in cell lysis and solute leakage. Together, these results support the inhibitory effect of nZVI on M. aeruginosa and provide insights to guide metabolomics studies of M. aeruginosa using nZVI. Full article

In this work, we have synthesized a more acid-stable variant of the classic chromophore difluoro-Bodipy by substituting the difluoro ligands at boron with cyano groups. This dicyano-Bodipy variant allowed the in situ incorporation during the MOF formation under acidic conditions and was investigated for the first time as dye@MOF composites using both post-synthetic and in situ incorporation into the zirconium-based metal–organic frameworks (MOFs) UiO-66, MOF-808, DUT-67, and MIP-206. The successful incorporation of dicyano-Bodipy was confirmed by PXRD, N₂ sorption, digestion UV–Vis, and fluorescence spectroscopy. Depending on the incorporation method used, significant lower BET surface areas could be determined. The luminescence properties of the resulting dicyano-Bodipy@MOF composites from the in situ incorporation had up to almost eight-fold extended photoluminescent lifetimes of 9.0 ns, compared to the neat dye in its solid state with 1.2 ns, which suggests the formation of a solid solution in which the incorporated Bodipy is protected from external influences within a well-defined MOF pore. The quantum yield could be enhanced to as high as 77% through post-synthetic incorporation into the MOF DUT-67, compared to the neat dye in its solid state, with 9%. Full article

Post-translational modifications (PTMs) are critically important for protein structure and function, with glycosylation being one of the most common forms of PTM. The gastric pathogen Helicobacter pylori has a general glycosylation system, which performs complex glycosylation of lipopolysaccharide, flagella proteins, and outer membrane proteins (OMPs). One of the best-described OMPs of H. pylori is the blood group binding adhesin (BabA), which interacts with the Lewis histo-blood group antigen, Lewis b. The 3D structure for BabA has been determined, and the ligand specifically described. Although BabA is reported to be a glycoprotein, there are limited data examining the effects of glycosylation on the structure and function of this protein. This study examined the folding and thermostability of non-glycosylated recombinant BabA and used computational approaches to predict the effect of glycosylation on the protein, with a focus on its possible heterologous expression in mammalian cells. Three potential O-linked and three potential N-linked glycosylation sites were predicted. Furthermore, the effect of glycan shielding on the solvent-accessible surface area of BabA was examined. Molecular dynamics simulations highlighted local indicators, including root mean square fluctuation and the number of protein-glycan contacts that were affected by glycosylation. Taken together, the findings support a role of glycans in surface shielding and promoting local stabilization in specific areas of the BabA protein. This study helps to strengthen the understanding of the importance of glycosylation and the role it plays in the structure, function, and stability of H. pylori proteins. Full article

Background: Nitric oxide (NO)-related biomarkers, including asymmetric dimethylarginine (ADMA), nitric oxide (NO), and endothelial nitric oxide synthase (eNOS), may play a role in the pathophysiology and clinical progression of chronic obstructive pulmonary disease (COPD). This study aimed to investigate their diagnostic value in stable COPD and acute exacerbation. Methods: A total of 150 participants (76 females, 74 males; mean age 53.82 ± 7.06 years) were enrolled and equally distributed into control, stable COPD, and acute exacerbation groups (n = 50 each). Demographic, clinical, and laboratory parameters were compared across groups. Serum ADMA, NO, and eNOS levels were analyzed, and correlations with clinical findings were evaluated. ROC analysis was performed to determine the diagnostic performance of the biomarkers. Results: Serum ADMA levels were significantly higher in COPD patients, particularly in the acute exacerbation group (p < 0.05 for all comparisons). In contrast, NO and eNOS levels were significantly lower in COPD groups compared to controls (p < 0.05 for all comparisons). ADMA showed strong negative correlations with FEV₁, FEV₁/FVC, PaO₂, and SaO₂, whereas NO and eNOS showed positive correlations with the same parameters (all p < 0.01). For predicting acute exacerbation, an ADMA cut-off of 1.36 yielded high diagnostic accuracy (AUC = 0.983; sensitivity 86.0%; specificity 96.0%). eNOS also demonstrated predictive value (AUC = 0.823). For stable COPD, NO at a cut-off of 14.91 showed excellent diagnostic performance (AUC = 0.921). Conclusions: NO-related biomarkers, particularly ADMA and NO, may serve as reliable indicators for differentiating between stable COPD and acute exacerbation. Elevated ADMA and reduced NO and eNOS levels were closely associated with impaired lung function and oxygenation parameters. These findings suggest potential clinical utility of these biomarkers in COPD monitoring and management. Full article