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In silico DFT, ADMET and molecular docking studies of novel coumarin-linked pyrazole and quinoline derivatives as antimicrobial and antioxidant agents
Abstract Ten novel coumarin-based hybrids comprising coumarin–pyrazole ( 7a–e ) and coumarin–quinoline ( 11a–e ) derivatives were synthesized via multistep reactions and characterized spectroscopically. Solvent optimization identified DMF: Ethanol (1:1) with H 2 SO 4 as optimal conditions, achieving 88% yield in 2–3 h. Antimicrobial evaluation against four bacterial strains ( Bacillus subtilis , Staphylococcus aureus , Escherichia coli , Acinetobacter baumannii ) and one fungal strain ( Aspergillus niger ) revealed compound 7a as the most potent (MIC: 25 μg/mL), superior to standard drugs. Antioxidant screening showed that 7a exhibited excellent activity (IC 50 : 20.23 ± 0.29 mg/mL), comparable to that of ascorbic acid. Molecular docking against three target proteins (4WMZ, 5FNR, 4LOL) demonstrated strong binding affinity, with 7b showing the highest docking score (− 9.71186 kcal/mol) against 4WMZ. Notably, compound 7b showed the highest predicted binding affinity in silico, whereas compound 7a demonstrated the superior experimental antimicrobial activity; this discrepancy underscores that docking scores offer predictive, not confirmatory, evidence of biological potency. DFT calculations (B3LYP/6–311++ G(d,p)) elucidated electronic properties, including HOMO–LUMO gap (3.8640 eV), Mulliken charge distribution, RDG, ELF, LOL, thermodynamic parameters, and global reactivity descriptors. In silico ADMET profiling revealed favorable physicochemical and drug-like properties for most derivatives; however, uniformly high predicted genotoxicity scores (> 0.99) and moderate hERG cardiotoxicity liability were identified, highlighting the need for rigorous experimental safety validation prior to further development. This integrated approach establishes coumarin–pyrazole and coumarin–quinoline hybrids as promising multifunctional therapeutic agents with antimicrobial and antioxidant potential.
Characterizing Gateway Modes for Solid–Solid Phase Transitions in Organic Crystals: The Thermosalient 4-DBpFO
Association of Chemerin, follicle stimulating hormone, lipid profiles, and cardiometabolic indices with the premature ovarian insufficiency
Food insecurity and at-home vegetable and sugar-sweetened beverage availability: TX Sprouts randomized controlled trial
Wavelength-Dependent Nitrogen Fixation and Hydrogenation to Ammonia over Lithium Hydride Catalyst
Exploring the association between physical activity and life satisfaction among college students
Evaluation of sap extraction methods for nutrient diagnostics in lettuce, cucumber, and tomato in controlled environments
Partially Reduced PtO Promoted Activation of Oxygen and Ammonia for Ambient Photocatalytic Ammoxidation
Experimental and CFD Investigation of inlet fin influence on compressor stability and performance
Abstract The operational stability and overall performance of turbocharger compressors are influenced by local as well as global instability phenomena under off-design conditions. This paper investigates the suppression of inlet recirculation and enhancement of surge operating range, using inlet fins. Both experiments and high-fidelity CFD simulations were used to assess the effect of fins on compressor performance, stability, and operating range. Experiments were conducted on a small turbocharger, while numerical simulations were performed using the RANS equations coupled with the k–ω SST turbulence model solved by ANSYS CFX. The numerical approach was validated, and a mesh independence study was conducted to evaluate discretization uncertainty at both design and off-design conditions. The results revealed that fins effectively suppressed upstream recirculation and preswirl, and promoted more uniform and directed flow into the impeller. Under stable, high-flow conditions, fins had a negligible influence on pressure ratio and efficiency. However, at low flow rates near surge, their presence significantly enhanced compressor performance. Pressure ratio increased by up to 5.4%, while the surge mass flow rate decreased by 8.4–10.4%, indicating a substantial extension of the stable operating range. Despite an efficiency penalty of up to 5% at low flow rates, the compressor performance at medium and high flow rates remains unaffected. The flow field analyses revealed that fins reduced swirl velocity, maintained higher incidence angles, and limited upstream momentum exchange, thereby stabilizing near-surge operation.
Redox Control in a Conducting MOF through Coupled Electronic–Vibronic Effects
Mitigating copper toxicity in Carthamus tinctorius L. through 6-benzylaminopurine during seed germination and vegetative growth
Nanosensor Quantifying Lysosomal Glycosidase Secretion from Single Living Cells
Expected KL risk quantifies when first-order power-law approximations are sufficient
Abstract Biochemical Systems Theory (BST) often replaces nonlinear rate laws by first-order log–Taylor power-law approximations, but deciding when this truncation is adequate remains difficult. We derive a closed-form leading-order expression for the expected conditional Kullback–Leibler (KL) risk incurred by using the first-order model instead of the local second-order log expansion. Under Gaussian log-input fluctuations with covariance $$\Sigma$$ and homoscedastic Gaussian log-output noise with variance $$s^2$$ , the risk reduces to a trace contraction of the local log-curvature Hessian H with $$\Sigma$$ . The criterion is therefore directly estimable from perturbation data or mechanistic models near an operating point. We also identify the leading correction from non-Gaussian inputs through fourth-order cumulants. Toy-model calculations and two biochemical case studies show that the criterion not only matches Monte Carlo estimates, but also identifies operating conditions and perturbation directions for which first-order BST is expected to fail.
Data Science and High-Throughput Spectroelectrochemistry-Guided Interrogation of Sulfonate Anions for OMIECs
Assessment of tribological performance and thermal stability of metakaolin-based geopolymer composites reinforced with high TiO2 concentration
Abstract This study investigates the influence of titanium dioxide (TiO 2 ) incorporation (0–50 wt.%) on the structural, thermal, and tribological properties of metakaolin-based geopolymer composites (GPCs). The bulk density of the composites increased progressively from 1.81 g/cm 3 for the control sample to 2.86 g/cm 3 at 50 wt.% TiO 2 , while apparent porosity decreased from 33.47 to 23.48%. Water absorption was correspondingly reduced from 8.43 to 5.34% after 24 h immersion, confirming the pore-filling effect of TiO 2 . XRD and FTIR analyses indicated the coexistence of amorphous aluminosilicate gel, residual quartz, and anatase reflections, with Ti–O and Ti–O–Si vibrations confirming the physical embedding of TiO 2 without disrupting the geopolymeric framework. SEM micrographs revealed that higher TiO 2 content led to a denser morphology with fewer pores, confirming densification. DSC/TGA revealed that TiO 2 addition enhanced stability and reduced low-temperature mass loss. Pin-on-disc testing showed that adding 40 wt.% TiO 2 significantly improved tribological performance, reducing the wear rate from 3.45 × 10 −5 to 1.12 × 10 −5 mm 3 /N m and the steady-state friction coefficient from 0.36 to 0.29. These results confirm the dual role of TiO 2 as a microstructural densifier and a reinforcing agent, enabling the development of geopolymer composites with enhanced durability, thermal stability, and wear resistance suitable for high-performance structural applications in extreme environments.
Frequency, clinical characteristics and cataract surgery outcomes of pseudoexfoliation syndrome in patients with senile cataracts: a review of hospital-based data
Unraveling Synergistic Dual-Element Doping Mechanisms in Solid-State Synthesis via Atomic Layer Deposition-Enabled Model Systems
Impact of ESG performance of China’s listed energy companies on their going global performance
Abstract The energy sector stands as the foremost battleground for Chinese companies seeking to expand overseas. It is worth investigating whether listed energy companies can leverage their ESG performance to forge new competitive advantages in the international market, navigate the high standards and stringent regulations of the global arena, and propel them to go global. Using panel data of 1,882 firm-year observations of Chinese A-share listed energy companies from 2013 to 2023, this study examines the association between ESG performance and internationalization performance measured by overseas revenue. Fixed-effects regression models are employed to control for unobserved heterogeneity. The main findings are as follows: (1) ESG performance is positively and significantly associated with internationalization performance ( β = 0.7816, p < 0.01), and the result remains robust across multiple robustness checks. (2) Mechanism analysis shows that ESG performance enhances internationalization outcomes by improving corporate reputation ( β = 0.5045, p < 0.01) and promoting green innovation capability ( β = 0.3740, p < 0.01). (3) Heterogeneity analysis indicates that the positive association is stronger for state-owned energy companies and companies operating in the new energy segment and in the non-Belt and Road Initiative countries. These results provide quantitative evidence that ESG practices are closely linked to international expansion outcomes in the energy sector. The policy implications are that regulators may strengthen standardized ESG disclosure and verification to reduce information asymmetry in cross-border markets. Companies can embed ESG governance into overseas compliance and green innovation strategies to enhance internationalization outcomes.