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Lead‐free organic–inorganic metal halide perovskites have attracted wide attention owing to their outstanding photophysical properties. Herein, a new type of antimony‐doped 0D tin(IV)‐based organic–inorganic metal halide hybrid (C10H16N2)SnCl6:Sb with highly efficient luminescence and remarkable stability is reported. Upon photoexcitation, the prepared samples exhibit an ultrabroadband emission ranging from 400 to 900 nm with two centers at 500 and 660 nm, which originate from free excitons and self‐trapped excitons, respectively. Such 0D metal halide hybrids with ultrabroadband emission covering the entire visible spectrum are rare. Especially, the photoluminescence quantum yield (PLQY) of red emission is as high as 77% upon 345 nm ultraviolet excitation. More importantly, (C10H16N2)SnCl6:Sb exhibits relatively good stability. It can still maintain 90% photoluminescence intensity after one week of 365 nm ultraviolet irradiation. Simultaneously, its PL intensity still retains 61% of room temperature emission intensity at 400 K. This work provides a new direction for the development of 0D organic–inorganic metal halide hybrids with excellent performance. [ABSTRACT FROM AUTHOR]

Oral ingestion of curcumin is claimed to be effective against several diseases, including inflammation and cancer. However, its utilization in food, supplement, and pharmaceutical products is often challenging due to its poor water solubility, high chemical instability, and limited oral bioavailability. Emulsion-based delivery systems can be designed to overcome these challenges, but their composition and structure must be optimized to ensure they function appropriately. This study examined the impact of emulsifier type on the formation and stability of curcumin-loaded oil-in-water emulsions: sodium caseinate; Tween 80; quillaja saponin; gum arabic. The effectiveness of these food-grade emulsifiers at forming emulsions by microfluidization was characterized in terms of their surface load, i.e., the mass of emulsifier per unit surface area. The surface loads decreased in the following order: gum arabic (55.3 mg/m 2 ) > > saponins (2.0 mg/m 2 ) > Tween 80 (1.6 mg/m 2 ) > caseinate (1.5 mg/m 2 ), which indicated that much more gum arabic was required to form emulsions than the other emulsifiers. Curcumin-loaded emulsions were then prepared under conditions where there was just enough emulsifier to cover the droplet surfaces (“critical”), and under conditions where there was an excess of emulsifier in the aqueous phase (“excess”). Initially, both critical and excess emulsions were physically stable and had similar appearances. In all emulsions, curcumin degradation during storage occurred more rapidly at pH 7 than at pH 3, and was faster at 55 °C than at 37 °C. The physical and chemical stability of the curcumin-loaded emulsions also depended on emulsifier type. After storage at 55 °C for 15 days, the extent of curcumin degradation decreased in the following order: saponins > > gum arabic ≈ casinate ≈ Tween 80. Moreover, droplet creaming was observed in the critical Tween 80 and saponin emulsions, but not in the other emulsions. These results suggest that saponin accelerated curcumin degradation, possibly due to its ability to promote peroxidation reactions. Emulsifier concentration did not significantly affect curcumin degradation. These results suggest that the physical and chemical stability of curcumin-loaded emulsions is influenced by emulsifier type and level. This information may be useful for formulating emulsion-based delivery systems for curcumin with improved physicochemical and functional properties. [ABSTRACT FROM AUTHOR]

This paper is concerned with the synchronization problem for a class of switched neural networks (SNNs) with time-varying delays. First, a new crucial lemma which includes and extends the classical exponential stability theorem is constructed. Then by using the lemma, new algebraic criteria of $\psi $ -type synchronization (synchronization with general decay rate) for SNNs are established via the designed nonlinear feedback control. The $\psi $ -type synchronization which is in a general framework is obtained by introducing a $\psi $ -type function. It contains exponential synchronization, polynomial synchronization, and other synchronization as its special cases. The results of this paper are general, and they also complement and extend some previous results. Finally, numerical simulations are carried out to demonstrate the effectiveness of the obtained results. [ABSTRACT FROM PUBLISHER]

Abstract: In this paper, we consider a differential–algebraic biological economic system with time delay and harvesting where the dynamics is logistic with the carrying capacity proportional to prey population. By considering the time delay as bifurcation parameter, we analyze the stability and the Hopf bifurcation of the differential–algebraic biological economic system based on the normal form approach and the center manifold theory. At last, numerical simulations are performed to illustrate the analytical results. [Copyright &y& Elsevier]

Abstract: In this paper, we consider a differential–algebraic biological economic system with time delay where the model with Holling type II functional response incorporates a constant prey refuge and prey harvesting. By considering time delay as bifurcation parameter, we analyze the stability and the Hopf bifurcation of the differential–algebraic biological economic system based on the new normal form approach of the differential–algebraic system and the normal form approach and the center manifold theory. Finally, numerical simulations illustrate the effectiveness of our results. [Copyright &y& Elsevier]

Abstract: To improve the stability of potassium ferrate(VI) (K2FeO4) cathode and its properties of charge transfer in alkaline battery system, K2FeO4 cathodes are coated by yttria (Y2O3) doped zirconia (ZrO2) composites, denoted as Y2O3–ZrO2 composite coatings. These composite coatings are derived from the conversion of yttrium nitrate (Y(NO3)3·6H2O) and Zirconium oxychloride (ZrOCl2·6H2O) in ether medium. Examinations by scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FT-IR) show that K2FeO4 cathodes are coated by Y2O3–ZrO2 overlayer. Alternatively, results of discharge properties and electrochemical impedance spectroscopes (EIS) indicate that when the molar ratio between Y2O3 and ZrO2 is 0.09, denoted as Y2O3 (9mol%)–ZrO2, the stability and charge transfer of Y2O3 (9mol%)–ZrO2 coated K2FeO4 cathodes are improved greatly compared to that of uncoated or ZrO2 coated K2FeO4 cathodes. Therefore, Y2O3–ZrO2 composite coatings are a potential choice to improve the stability and charge transfer of K2FeO4 cathodes in alkaline electrolyte. [Copyright &y& Elsevier]

Abstract: In this paper, we analyze the stability and Hopf bifurcation of the biological economic system based on the new normal form and the Hopf bifurcation theorem. The basic model we consider is owed to a ratio-dependent predator–prey system with harvesting, compared with other researches on dynamics of predator–prey population, this system is described by differential-algebraic equations due to economic factor. Here μ as bifurcation parameter, it is found that periodic solutions arise from stable stationary states when the parameter μ increases close to a certain limit. Finally, numerical simulations illustrate the effectiveness of our results. [ABSTRACT FROM AUTHOR]

In this paper, a genetic regulatory network with two time delays is considered. Firstly, the stabilities with one delay and two delays are investigated. It is shown that the stability switches for time delays, and Hopf bifurcation may occur within certain range of the model parameters. Then, combining the normal form method and the center manifold theorem, we derive the explicit formulas which determine the direction of the bifurcation and the stability of the bifurcated periodic solutions. Finally, some numerical examples are exploited to support our results. [ABSTRACT FROM AUTHOR]

This study aimed to determine the capacity of 7,7′-bromo-curcumin (CUR-Br), a curcumin analogue with higher chemical stability than curcumin (CUR), in the suppression of mouse ear edema. Male CD-1 mice were topically pre-treated with either CUR or CUR-Br for 30 min prior to an application of 12- O -tetradecanoylphorbol-13-acetate. After 6 h, mice were killed, and ear punches were measured for their weight and thickness as a marker of edema and inflammation. CUR-Br demonstrated a higher anti-inflammatory efficacy compared to CUR. CUR and CUR-Br at 1.0 μmol suppressed the TPA-induced increase in the ear weight by 26.0% and 57.2%, and decreased TPA-induced increase in the ear thickness by 22.2% and 84.7%, respectively. The inhibitory effects of Cur-Br were associated with decreased levels of inflammatory cytokines (IL-1β, IL-2, IL-6, KC/GRO, IL-10, IL-17, and IL-23). In addition, CUR-Br significantly downregulated expression of pro-inflammatory signaling proteins such as p-STAT3, STAT3, PI3K, AKT, p-p65, and COX-2. Overall, our results demonstrated that the curcumin analogue, CUR-Br, showed stronger anti-inflammatory properties than CUR in inhibiting TPA-induced inflammatory response in mouse skin. [ABSTRACT FROM AUTHOR]