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Molecular dynamics simulations have been carried out to investigate the fluid wetting and flow in nanochannels whose surfaces are structured by an array of nanoscale triangular modules. We find that the surface nanostructures have a dual effect on the boundary slip and friction of the liquid nanoflow. On the one hand, the nanostructures can enhance the surface hydrophilicity for a hydrophilic liquid-solid interaction, and can increase the hydrophobicity for a hydrophobic interaction due to a nanoscale lotus effect. In particular, the nanostructured surface may show superhydrophobicity and lead to the large velocity slip of the liquid flow. On the other hand, simultaneously, the nanostructures distort the nanoscale streamlines of the liquid flow near the channel surfaces and block the nanoflow directly, which decreases the apparent slip length equivalently. The dual effect of the nanostructures on the surface wettability and the hydrodynamic disturbance results in a nonmonotonic dependence of the slip length on the nanostructure size. The simulations imply that the surface nanostructures can be applied to control the friction of liquid micro-and nanoflows.

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This paper reports a versatile method to fabricate robust carbon/metal hybrids with ultrasmall particle and highly developed porous structure through a scalable and facile way. Alginate is used as the precursor for it could perform cross-linking reaction with different polyvalent metal ions to form gels. After simple freeze-drying and carbonization of the alginate-derived gels, we obtained the carbon/metal hybrids with fine nanostructure. Eleven kinds of metal ions were introduced to form gels and five kinds of the gels were carbonized to produce the carbon/metal hybrids. By adjusting the reaction condition, we could tune the size of the nanoparticles in the obtained hybrids. The obtained SnO2/C hybrid shows outstanding specific capacity, rate performance, and long cycle life when it is used as the anode materials of lithium ion batteries. The ultrasmall active nanoparticles were uniformly dispersed within an interconnected pore framework. It ensured a short diffusion and transportation distance of electrolyte ions to the surfaces of active nanoparticles. In addition, the robust carbon framework comprises of quasigraphitic carbon layers. It contributed to the high rate performance by providing excellent conductive pathways for electrons within the electrodes. This work provides a general method for fabrication of carbon/metal (oxide) hybrids with fine nanostructure for application in energy storage.

Background: Sepsis-associated liver injury (SALI) is a risk factor of poor outcome in patients with sepsis. The early warning biomarkers for identifying SALI remain poorly defined. Aims: To identify the potential predictors of occurrence of SALI in pediatric patients with sepsis. Methods: We retrospectively analyzed the sepsis database based on the medical records of patients admitted to the pediatric intensive care unit (PICU) in Shanghai Children's Hospital from July 2014 to June 2018. Patients' demographics, co-morbidities and laboratory variables were collected. Univariate and multivariate logistic analysis were used to explore risk factors of SALI, and receiver operating characteristic (ROC) curve analysis was used to evaluate their predictive significances for SALI occurrence. Results: Of 1,645 eligible patients, 1,147 patients were included, and 105 cases had SALI. The indexes including AST-to-platelet ratio index (APRI), γ-GT and lactate dehydrogenase (LDH) were independent risk factors for SALI. Moreover, APRI was powerful to predict SALI in children (AUC: 0.889, 95% CI : 0.851–0.927) with a sensitivity of 84.6 % and a specificity of 84.3 % at the cutoff point of 0.340. APRI was superior to LDH and not inferior to γ-GT for predicting SALI. Conclusion: APRI is an independent risk factor of SALI occurrence, and elevated APRI within 24 h after PICU admission (>0.340) is a potential predictor for SALI in children.

Controllable layer‐structured 3D photonic crystals (PCs) are prepared using the combination of the Langmuir–Blodgett (LB) technique and layer‐by‐layer stacking method. They are used for research into the influence of the number of the layers on the enhancement of the efficiency of light emission from light‐emitting diodes (LEDs) and quantum dots (QDs). The luminescence properties of blue, green, and white LEDs are improved dramatically while applying such controllable layer‐structured 3D PCs as reflectors and the enhancement efficiencies are shown to increase with PC thickness. In addition, the fluorescence intensity increases 7.8‐fold and 5.4‐fold for red and green QDs, respectively, and the fluorescence intensity can be accurately controlled by using PCs with different layers. In addition, PC beads with yellow and red photonic bandgaps are used to improve the luminescence of a white LED with angle‐independent enhancement. These beads are simply doped into the phosphor without any other treatment. Interestingly, the light intensity of the PC bead based LED is remarkably enhanced. These quantized enhanced effect of light intensity on the thickness of PC layers, along with new generation of PC bead based LED, might offer a strategy for designing high brightness LEDs with energy‐saving performance.