Existence of positive solutions of mixed fractional integral boundary value problem with p(t)-Laplacian operator

Ricerche di Matematica - In this paper, we investigate a mixed fractional integral boundary value problem with p(t)-Laplacian operator. Firstly, we derive the Green function through the direct...     

Development and validation of LC–MS/MS method for amlexanox in rat plasma and its application in preclinical pharmacokinetics

Amlexanox, an anti-inflammatory and anti-allergic agent, has been widely used clinically for the treatment of canker sores, asthma, and allergic rhinitis. Recently, amlexanox has received considerable attention in curing nonalcoholic fatty liver diseases and hepatitis virus infection. Herein, we first established a sensitive high-performance liquid chromatography-tandem mass spectrum (LC–MS/MS) method for the determination of amlexanox in rat plasma. Propranolol was used as the internal standard (IS). Using a simple protein precipitation method, the amlexanox and IS were separated with Capcell Pak C18 column (2.0 × 50 mm, 5 μm) and eluted with water and acetonitrile each containing 0.1% formic acid using gradient elution condition at a flow rate of 0.4 mL·min⁻¹. Amlexanox and IS were detected by a triple quadrupole mass in multiple reactive monitoring (MRM) under the transitions of m/z 299.2 → 281.2 and m/z 259.9 → 116.1 with positive electrospray ionization, respectively. The calibration curves of amlexanox were established with the range of 50 to 2000 ng·mL⁻¹ (r² > 0.99). The validation method consisted of selectivity, accuracy, precision, carryover effect, matrix effect, recovery, dilution effect, and stability. The fully validated method was successfully applied to the pharmacokinetic study of amlexanox in Wistar rats.     

Modified Burgers-Reimschuessel model for moisture-sensitive polymers

Viscoelastic properties of moisture-sensitive polymers can be significantly affected by moisture in the ambient environment, resulting in drastic changes in the properties as the absorbed moisture content increases. In this article, a simple yet important modification to the Reimschuessel model is introduced by considering both plasticization and anti-plasticization induced by water molecules. The proposed model is validated against the results of four different polymers obtained by Onogi et al., which demonstrates its capability of describing the available data. This model can be used to estimate the performance and service life of products produced using moisture-sensitive polymers. It also reveals that small amounts of diffused moisture might have a stiffening effect on the mechanical properties of hydrophilic polymers.     

Dipolar Glass Polymers for Capacitive Energy Storage at Room Temperatures and Elevated Temperatures

Chinese Journal of Polymer Science - Dielectric polymers are the materials of choice for high energy density film capacitors. The increasing demand for advanced electrical systems requires...     

新型多孔材料用作色谱手性固定相

手性固定相是色谱法分离分析手性化合物的关键。近年来,随着材料科学的迅速发展,越来越多的新型手性材料被作为色谱固定相用于手性分离分析。本文综述了近5年来液相色谱、气相色谱和毛细管电色谱领域的新型手性固定相的研究进展,重点总结了基于手性多孔材料的新型手性固定相研究,最后对手性固定相的研究进行了总结与展望。     

Molecular Engineering of Chalcogen-Embedded Anthanthrenes via peri-Selective C−H Activation: Fine-Tuning of Crystal Packing for Organic Field-Effect Transistors

Disclosed herein is a RhCl₃-catalyzed peri-selective C−H/C−H oxidative homo-coupling of 1-substituted naphthalenes, which provides a highly efficient and streamlined approach to chalcogen-embedded anthanthrenes from readily available starting materials. Introducing O, S, and Se into the anthanthrene skeleton leads to gradually increased π–π stacking distances but significantly enhanced π–π overlaps with the growth of the hetero-atom radius. Moderate π–π distance, overlap area, and intermolecular S−S interactions endow S-embedded anthanthrene ( PTT ) with excellent 2D charge-transport properties. Moreover, the transformation of p-type to n-type S-embedded anthanthrenes is realized for the first time via the S-atom oxidation from PTT to PTT-O4 . In organic field-effect transistor devices, PTT derivatives exhibit hole transport with mobilities up to 1.1 cm² V⁻¹ s⁻¹, while PTT-O4 shows electron transport with a mobility of 0.022 cm² V⁻¹ s⁻¹.     

IL-2-loaded Polypeptide Nanoparticles for Enhanced Anti-cancer Immunotherapy

Interleukin 2(IL-2) is widely used as an active immunotherapeutic agent in clinical metastatic cancers. However, its therapeutic concentrations do not last long due to its short half-life. Thus, only a transient proliferation of the anti-cancer CD8⁺ T cells can be achieved,resulting in poor efficacy. Therefore, the aim of this work was to create a system that promotes CD8⁺ T cell proliferation at the tumor site using IL-2 persistently present and activates an anti-cancer im...     

C−N Coupling through Hydroaminoalkylation on a Single-Atom Rh Heterogeneous Catalyst

C−N coupling is significant for the synthesis of fine chemicals toward various applications. Hydroaminoalkylation of olefins is a tandem reaction of C−N coupling involving first the formation of an aldehyde through hydroformylation of an olefin and then the production of amine through reductive amination of the aldehyde. Here we report a stable, supported catalyst of singly dispersed Rh₁ atoms anchored on TiO₂ (P25) nanoparticles designated as Rh₁/P25. Its high activity for C−N coupling was demonstrated by six hydroaminoalkylations of olefins and amines with selectivity of higher than 90% for producing tertiary amines. The singly dispersed Rh₁O₄ on P25 exhibit activity and selectivity for hydroaminoalkylation comparable or even higher than some reported molecular catalysts. In contrast to molecular catalysts, the Rh-based single-atom Rh heterogeneous catalysis (Rh₁/P25) can be readily separated from reactants and products, reused for multiple runs of hydroaminoalkylation, and recycled with a low cost.