Breast milk fatty acid composition may be affected by the maternal diet during gestation and lactation. The influence of dietary and breast milk fatty acids on breast milk immune factors is poorly defined. We determined the fatty acid composition and immune factor concentrations of breast milk from women residing in river/lake, coastal and inland regions of China, which differ in their consumption of lean fish and oily fish. Breast milk samples were collected on days 3 -5 (colostrum), 14 and 28 post-partum (PP) and analysed for soluble CD14 (sCD14), transforming growth factor (TGF)-b1, TGF-b2, secretory IgA (sIgA) and fatty acids. The fatty acid composition of breast milk differed between the regions and with time PP. The concentrations of all four immune factors in breast milk decreased over time, with sCD14, sIgA and TGF-b1 being highest in the colostrum in the river and lake region. Breast milk DHA and arachidonic acid (AA) were positively associated, and g-linolenic acid and EPA negatively associated, with the concentrations of each of the four immune factors. In conclusion, breast milk fatty acids and immune factors differ between the regions in China characterised by different patterns of fish consumption and change during the course of lactation. A higher breast milk DHA and AA concentration is associated with higher concentrations of immune factors in breast milk, suggesting a role for these fatty acids in promoting gastrointestinal and immune maturation of the infant.

Freestanding and bendable films fabricated by two-dimensional (2D) MXene materials have demonstrated great potential as electrodes for energy storage devices owing to their paramount flexibility, structural stability, and high conductivity. Nevertheless, the unavoidable restacking of MXene sheets substantially limits their electrochemical performance. Here, a film electrode with a sandwich-like structure was fabricated by a dual-structural design through a layer-by-layer (LbL) method with alternating filtration of the Ti 3 C 2 T x /carbon nanotube (CNT) hybrid and CuS dispersion. The introduced CNTs and pseudocapacitive CuS provide abundant active sites to augment the electrode storage capacity. The enlarged interlayer spacing facilitates the transport of electrolyte ions. As a result, the optimized Ti 3 C 2 T x /CNTs/CuS-LbL-15 film electrode (1.7 mg/cm 3 ) with a thickness of 17 μm still exhibits a high gravimetric capacitance (336.7 F/g) and volumetric capacitance (572.4 F/cm 3 ) at 1 A/g in a poly(vinyl alcohol) (PVA)/H 2 SO 4 gel electrolyte, both of which are among the highest within past reports at the same thickness. Meanwhile, the sample demonstrates an impressive rate capability with 57% capacitance retention at a current density of 9 A/g, ultrastable cycling by retaining 99.6% of the initial capacity after 5000 cycles at a high rate of 5 A/g, and good flexibility under different bending states. Besides, the all-solid-state symmetric supercapacitor exhibits an energy density of 12.72 Wh/L at a power density of 340 W/L. This work provides an effective route for assembling Ti 3 C 2 T x /CNTs and CuS hybrid electrodes for high-performance energy storage devices.

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In this paper, we consider the numerical approximation for a phase field model of the coupled two-phase free flow and two-phase porous media flow. This model consists of Cahn-Hilliard-Navier-Stokes equations in the free flow region and Cahn-Hilliard-Darcy equations in the porous media region that are coupled by seven interface conditions. The coupled system is decoupled based on the interface conditions and the solution values on the interface from the previous time step. A fully discretized scheme with finite elements for the spatial discretization is developed to solve the decoupled system. In order to deal with the difficulties arising from the interface conditions, the decoupled scheme needs to be constructed appropriately for the interface terms, and a modified discrete energy is introduced with an interface component. Furthermore, the scheme is linearized and energy stable. Hence, at each time step one need only solve a linear elliptic system for each of the two decoupled equations. Stability of the model and the proposed method is rigorously proved. Numerical experiments are presented to illustrate the features of the proposed numerical method and verify the theoretical conclusions. B111However, most of the existing works on the Stokes-Darcy model are devoted to single-phase flows, and hence they cannot be used for the applications of multiphase flow. Recently, researchers [19,28,48,51,53] started to develop the models to couple the porous media flow with the two-phase free flow, for which the phase field method is adopted. In [19], Chen, Sun, and Wang utilized the Cahn-Hilliard-Navier-Stokes (CHNS) equation to govern the two-phase fluid system, and the two-phase Darcy's law for the two-phase porous medium flow. The coupling between these two equations is through the interface conditions including the generalized Navier boundary condition [80,81,82]. In [28], a modified Cahn-Hilliard equation is coupled with an unsteady Darcy-Stokes model, which uses the same equation with different coefficients for both Darcy and Stokes flows without interface transmission conditions. In [48,51,53], a Cahn-Hilliard-Stokes-Darcy (CHSD) system and a Cahn-Hilliard-Navier-Stokes-Darcy (CHNSD) system are developed for two-phase incompressible flows in the karstic geometry. It is remarkable that the CHNS equation is utilized to govern the two-phase free fluid, which is similar to [19]. However, in the porous media region, the Cahn-Hilliard-Darcy (CHD) equation is used instead of the twophase Darcy's law. Therefore, the interface conditions in [48,51,53] couple these two equations together that are different from those of [19]. Furthermore, two coupled, unconditionally stable numerical algorithms, which combine two Cahn-Hilliard equations in the Stokes and Darcy domains into one Cahn-Hilliard equation on the whole domain, are proposed and analyzed for the CHSD system in [48]. A "partially" decoupled and nonlinear scheme, which still directly solves one Cahn-Hilliard equation on the whole domain but decouples the Stokes and Darcy...

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