New Approach to Calculating the Double Coaxial Resonator with a Shortening Capacitance

Russian Physics Journal - The double coaxial resonator with a shortening capacitance is calculated by the partial volume method. The double resonator is represented by two single coaxial resonators...     

Regularized Divergences Between Covariance Operators and Gaussian Measures on Hilbert Spaces

Journal of Theoretical Probability - This work presents an infinite-dimensional generalization of the correspondence between the Kullback–Leibler and Rényi divergences between Gaussian...     

Infinite-dimensional Log-Determinant divergences between positive definite Hilbert–Schmidt operators

Positivity - The current work generalizes the author’s previous work on the infinite-dimensional Alpha Log-Determinant (Log-Det) divergences and Alpha-Beta Log-Det divergences, defined on the...     

pH-temperature Responsive Hydrogel-Mediated Delivery of Exendin-4 Encapsulated Chitosan Nanospheres for Sustained Therapeutic Efficacy in Type 2 Diabetes Mellitus

Type 2 Diabetes Mellitus (T2D) is a chronic, obesity-related, and inflammatory disorder characterize by insulin resistance, inadequate insulin secretion, hyperglycemia, and excessive glucagon secretion. Exendin-4 (EX), a clinically established antidiabetic medication that acts as a glucagon-like peptide-1 receptor agonist, is effective in lowering glucose levels and stimulating insulin secretion while significantly reducing hunger. However, the requirement for multiple daily injections due to EX's short half-life is a significant limitation in its clinical application, leading to high treatment costs and patient inconvenience. To address this issue, an injectable hydrogel system is developed that can provide sustained EX release at the injection site, reducing the need for daily injections. In this study, the electrospray technique is examine to form EX@CS nanospheres by electrostatic interaction between cationic chitosan (CS) and negatively charged EX. These nanospheres are uniformly dispersed in a pH-temperature responsive pentablock copolymer, which forms micelles and undergoes sol-to-gel transition at physiological conditions. Following injection, the hydrogel gradually degraded, exhibiting excellent biocompatibility. The EX@CS nanospheres are subsequently released, maintaining therapeutic levels for over 72 h compared to free EX solution. The findings demonstrate that the pH-temperature responsive hydrogel system containing EX@CS nanospheres can be a promising platform for the treatment of T2D.     

Real-time tracking of hydrogen peroxide secreted by live cells using MnO2 nanoparticles intercalated layered doubled hydroxide nanohybrids

We report a facile and green method for the fabrication of new type of electrocatalysts based on MnO₂ nanoparticles incorporated on MgAl LDH P-type semiconductive channel and explore its practical applications as high-performance electrode materials for electrochemical biosensor. A series of MgAl layered doubled hydroxide (LDH) nanohybrids with fixed Mg/Al (M²⁺/M³⁺ atomic ratio of 3) and varied amount of MnCl₂.4H₂O are fabricated by a facile co-precipitation method. This approach demonstrates the combination of distinct properties including excellent intercalation features of LDH for entrapping nanoparticles and high loading of MnO₂ nanoparticles in the host layers of LDH. Among all samples, Mn5–MgAl with 0.04% loaded manganese has a good crystalline morphology. A well-dispersed MnO₂ nanoparticles encapsulated into the host matrix of hydrotalcite exhibit enhanced electrocatalytic activity towards the reduction of H₂O₂ as well as excellent stability, selectivity and reproducibility due to synergistic effect of good catalytic ability of MnO₂ and conductive MgAl LDH. Glass carbon electrode (GCE) modified with Mn5–MgAl possesses a wide linear range of 0.05–78 mM, lowest detection limit 5 μM (S/N = 3) and detection sensitivity of 0.9352 μAmM⁻¹. This outstanding performance enables it to be used for real-time tracking of H₂O₂ secreted by live HeLa cells. This work may provide new insight in clinical diagnosis, on-site environmental analysis and point of care testing devices.     

Synthesis of Arylated Benzofurans by Regioselective Suzuki–Miyaura Cross‐Coupling Reactions of 2,3‐Dibromobenzofurans‐ and 2,3,5‐Tribromobenzofurans

Arylated benzofurans were prepared by regioselective Suzuki–Miyaura cross‐coupling reactions of 2,3‐dibromobenzofuran. The reactions proceeded with very good site‐selectivity in favor of the more electron deficient position 2. The Suzuki–Miyaura reactions of 2,3,5‐tribromobenzofuran also proceeded in favor of position 2.     

Hydrogen Peroxide Detection Using Prussian Blue-modified 3D Pyrolytic Carbon Microelectrodes

A highly sensitive amperometric Prussian blue-based hydrogen peroxide sensor was developed using 3D pyrolytic carbon microelectrodes. A 3D printed multielectrode electrochemical cell enabled simultaneous highly reproducible Prussian blue modification on multiple carbon electrodes. The effect of oxygen plasma pre-treatment and deposition time on Prussian blue electrodeposition was studied. The amperometric response of 2D and 3D sensors to the addition of hydrogen peroxide in μM and sub-μM concentrations in phosphate buffer was investigated. A high sensitivity comparable to flow injection systems and a detection limit of 0.16 μM was demonstrated with 3D pyrolytic carbon microelectrodes at stirred batch condition     

On the No-Gap Second-Order Optimality Conditions for a Discrete Optimal Control Problem with Mixed Constraints

Motivated by our recent works on optimality conditions in discrete optimal control problems under a nonconvex cost function, in this paper, we study second-order necessary and sufficient optimality conditions for a discrete optimal control problem with a nonconvex cost function and state-control constraints. By establishing an abstract result on second-order optimality conditions for a mathematical programming problem, we derive second-order necessary and sufficient optimality conditions for a discrete optimal control problem. Using a common critical cone for both the second-order necessary and sufficient optimality conditions, we obtain “no-gap” between second-order optimality conditions.     

Secondary Metabolites from the Fruiting Bodies of Coriolopsis aspera in Vietnam and their Bioactivities

Chemistry of Natural Compounds -