Florida National University is a private for-profit university in Hialeah, Florida. It was established in 1988. The student body is diverse, though primarily Hispanic. It is accredited by the Southern Association of Colleges and Schools (SACS).
Surface fronts are common features across the world's oceans, particularly in estuarine and coastal regions where the merging of freshwater and saltwater creates strong density gradients. It has long been documented that fronts in these regions can trap and concentrate various properties such as floating debris, nutrients, larvae, and other buoyant materials. The prediction of such fronts has important implications for environmental protection, search and rescue operations, and scientific research. However, the realistic simulation of such features remains a challenge. In this study, we apply a high‐resolution, numerical circulation model of Tampa Bay and the adjacent West Florida Shelf to predict surface fronts by computing surface convergence. The accuracy of the simulation is evaluated using drone and satellite imagery. The simulated convergence fields are then analyzed by a Self‐Organizing Map, an unsupervised machine learning method. Our findings show that convergence patterns vary with tidal phases (ebb and flood) as well as the spring–neap tidal cycle. This study provides a new framework for improving monitoring strategies and reducing observational bias. Although every estuary is unique, the physical mechanisms of frontogenesis are universal. Therefore, the method we propose can be applied to other estuarine systems and serve as a valuable tool for interdisciplinary research in estuarine and coastal environments.
Piezoresistive pressure sensors enable non-invasive pulse waveform monitoring by directly measuring arterial pressure, offering crucial insights for cuffless blood pressure monitoring systems. Unlike photoplethysmography (PPG), which estimates blood volume changes through light reflection and is prone to artifacts such as motion and ambient light interference, piezoresistive sensors offer direct mechanical detection, resulting in improved accuracy and reliability under dynamic conditions. This review explores the biomechanics of arterial pulse pressure, current methodologies for pulse waveform detection, and recent innovations in piezoresistive sensor materials and designs, including micropatterned and porous structures. Piezoresistive sensors excel in wearable applications due to their straightforward signal acquisition, lower susceptibility to noise, and high sensitivity across relevant pressure ranges. Additionally, the integration of artificial intelligence (AI), predominantly applied to PPG and electrocardiogram (ECG) data, is examined for its potential to enhance the analysis of mechanical pulse waveforms, enabling more robust anomaly detection and cardiovascular disease (CVD) prediction. By combining advances in sensor technology with AI-driven signal interpretation, piezoresistive sensors are poised to play a transformative role in developing continuous, non-invasive health monitoring systems. Future directions include addressing fabrication challenges, optimizing sensor design for motion artifact resistance, and expanding AI applications to leverage the unique benefits of piezoresistive technology.
High-temperature decomposition of pyridine, C5H5N, occurs during waste incineration, pyrolysis of biomass and coal. In the present work, the rate constants of H atom abstraction from C5H5N by H, CH3, CN, C2H3, CHCHCN and nC4H3 radicals have been calculated at the DLPNO-CCSD(T)-F12/cc-pVDZ-F12//M06-2X/def2-TZVP level of theory from 300 to 2000 K. The new rate constants obtained in the present work, in most cases are notably different from the expressions suggested in the earlier studies on pyridine pyrolysis or derived in theoretical calculations. Only for reactions of H atom abstraction by H, a reasonable agreement was found. It was revealed that the formation of ortho-, meta-, and para-pyridyls could be of equal importance and, therefore, all pyridyl isomers should be considered in detailed kinetic mechanisms for pyridine.
Reactions of the primary pyridine radicals, ortho-, meta-, and para-pyridyls with oxygen control the overall rate of pyridine oxidation. In the present work, the potential energy surfaces of o-, m-, and p-pyridyls + O2 previously developed by the authors have been employed for a systematic theoretical kinetic study of the rate constants of these reactions. The geometries of reactants, products, intermediates, and transition states of the reactions of pyridyl radicals with O2 were optimized at the level of density functional theory using the omega B97XD functional with the 6-311G** basis set. The temperature-and pressure-dependent rate constants of 31 reactions were evaluated within the framework of the Rice-Ramsperger-Kassel-Marcus (RRKM) theory combined with the Master Equation approach (RRKM-ME) in the temperature range from 300 to 3000 K, covering pressures from 0.01 to 100 atm. For several reactions previously investigated in the literature, good agreement was demonstrated, indicating consistency and correctness of the present theoretical calculations. Moreover, thermodynamic data for all important reactants, products, and intermediates have been revisited and calculated at the G4 theoretical level. The calculated rate constants and thermodynamic data provide a backbone for the development of detailed kinetic models for pyridine combustion.
Metal halides are an important class of optoelectronic materials combining exceptional optical and electronic properties. An inherent advantage of metal halides is their solution synthesis and processability, which render them as low-cost and environmentally friendly materials for a range of applications from photovoltaics and photodetection to solid-state lighting (SSL). In this study, we synthesized three previously unreported lead-free organic-inorganic hybrid copper halides: (OA)4CuX5 (X = Br, I; OA* = C8H17NH3* , n-octylammonium cation) and (HA)2CuI3 (HA* = C6H13NH3* , n-hexylammonium cation), all of which exhibit broadband emissions arising from self-trapped excitons (STEs). Among these compounds, (OA)4CuI5 demonstrates tunable dual-band white-light emission with a high color rendering index value of 91 at room temperature. Temperature-dependent photoluminescence measurements and first-principles calculations reveal distinct behaviors between the two emission states in (OA)4CuI5. These findings highlight the potential of copper halide compounds for optoelectronic applications, particularly in the development of environmentally friendly solid-state lighting technologies. (c) 2025 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights are reserved, including those for text and data mining, AI training, and similar technologies.
