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A MOF-based sacrificial template strategy is demonstrated to construct novel Mo-doped Co(OH) 2 hierarchical nanotubes organized by cross-linked porous nanosheets with the optimized electronic structure of more highly oxidative Co3+ species, which exhibits active and stable electrocatalytic activity for overall water splitting. • The Mo-doped Co(OH) 2 HNTs organized by cross-linked porous nanosheets are prepared. • Electronic structures with highly oxidative Co3+ species can be modified by Mo doping. • The low overpotentials of 218 mV and 125 mV for OER and HER are obtained. • Mo-Co(OH) 2 HNTs exhibit high electrocatalytic activity for overall water splitting. Designing hierarchical nanostructures of earth-abundant electrocatalysts for enhanced overall water splitting performance is of great significance. Herein, Mo-doped Co(OH) 2 hierarchical nanotubes (Mo-Co(OH) 2 HNTs) assembled by cross-linked porous nanosheets are designed and synthesized through a sacrificial template strategy. Benefiting from the hierarchical structures based on porous nanosheets with void interior as well as modified electronic structure of higher intensity of Co3+ species by Mo6+ doping, the Mo-Co(OH) 2 HNTs demonstrate superior electrocatalytic performance, achieving an current density of 10 mA cm−2 at the low overpotentials of 218 mV and 125 mV for oxygen and hydrogen evolution reactions, respectively. Furthermore, an overall water splitting cell was assembled with the Mo-Co(OH) 2 electrocatalyst as both the anode and cathode materials, which exhibits a driving voltage of as low as 1.62 V. The facile strategy presented in this work can be extended to the construction of various hollow/porous nanostructures with effective heteroatom doping to achieve low-cost, bifunctional and high-performance electrocatalysts for overall water splitting. [ABSTRACT FROM AUTHOR]

The effect of mean flow velocity on phosphorus (P) partitioning between water and sediment has received much attention in recent decades. However, the impact of turbulence on the efficiency and capability of sediment adsorbing and desorbing dissolved inorganic phosphorus (DIP) is still unclear. A series of contrasting experiments on the sediment sorption and desorption of DIP with the flow turbulence kinetic energy (TKE) ranging from 1.95 to 2.93 pa have been conducted. It was found that the adsorbed P onto unit mass of sediment increases with the increase in TKE. It is because an increase in TKE results in a rise in the effective adsorption capacity of sediment (b m) by 20–30% during the adsorption process. The b m shows the maximum rise from 0.18 to 0.25 mg/g when TKE increases from 1.95 to 2.93 pa with a fixed sediment concentration of 0.5 g/L. To account for the direct effect of TKE on P adsorption, the Langmuir model is modified by introducing a newly defined coefficient (f A − TKE). The f A − TKE shows a good linear relationship with TKE. Comparison between the modified model and the classic model shows that the amount of adsorbed P could be overestimated by over 50% if the direct effect of turbulence intensity is ignored. The experimental data show that the increase in TKE also enhances the desorption process, with the degree of P desorption (D des) increased by 44%. The relation between D des and TKE can be well represented using a logarithmic function to quantify the direct effect of turbulence intensity on desorption of P. [Display omitted] • The direct effect of turbulence on sediment adsorption and desorption of P is investigated. • The mathematic relationship between the effective adsorption capacity of sediment and TKE is established. • A new Langmuir model (TKE- SCA-Langmuir model) considering the direct effect of turbulence on P adsorption is built. • The direct effect of turbulence should be considered in numerical model to get realistic value of adsorbed P. [ABSTRACT FROM AUTHOR]

Understanding and quantifying mud suspension and sediment transport processes are of great importance for effective exploitation and sustainable management of estuarine environments. Event-based predictive models are widely used to identify the key interactions and mechanisms that govern the dynamics involved and to provide the essential parameterisation for assessing the long-term morphodynamic evolution of the estuaries. This study develops a one-dimensional-vertical (1DV) Reynolds averaged two-phase model for cohesive sediments resuspension driven by tidal flows. To capture the time-dependent flocculation process more accurately, a new drag force closure which relates empirically to settling velocity of mud flocs with suspended sediment concentration (SSC) is incorporated into the two-phase model. The model is then applied to simulate mud suspension in the Ems/Dollard estuary during two periods (June and August 1996) of tidal forcing. Numerical predictions of bed shear stresses and sediment concentrations at different elevations above the bed are compared with measured variations. The results confirm the importance of including flocculation effects in calculating the settling velocity of mud flocs and demonstrates the sensitivity of prediction with the settling velocity in terms of flocs concentration. Although the two-phase modelling approach can in principle better capture the essential interactions between fluid and sediment phases, its practical advantages over the simpler single phase approach cannot be confirmed for the data periods simulated, partly because the overall suspended sediment concentration measured is rather low and the interaction between the two phases is weak and also because the uncertainties in the relationship between the settling velocity and flocs concentration. [ABSTRACT FROM AUTHOR]

Nodal modulator 1 (NOMO1), a highly conserved transmembrane protein, has been identified as a part of a protein complex that participates in the Nodal signaling pathway, a critical determinant of heart and visceral organ formation. We previously found that the NOMO1 gene was substantially downregulated in human ventricular septal defect (VSD) myocardium and, thus, may be an important molecular pathway in human heart development. In this study, we aimed to investigate the effects of NOMO1 gene silencing by RNA interference (RNAi) during early mouse cardiac differentiation using P19 cells as a model system. Our results revealed that the differentiated P19 cell population exhibited downregulated NOMO1 levels and expressed lower levels of Nodal signaling mediators, such as Nodal, Cripto and Smad2, than the negative control. Similarly, cardiomyocyte-specific sarcomeric markers, such as cardiac troponin T, as well as expression of cardiogenesis-related transcriptional factors, such as Nkx 2.5, Gata 4 and Tbx 5 were found to be downregulated in P19 differentiated cardiomyocytes in NOMO 1-silenced cells when compared to controls. In conclusion , our results indicate that NOMO1 gene knockdown inhibits the differentiation of P19 cells into cardiomyocytes, which highlights a potential role for NOMO 1 in early cardiogenesis. [ABSTRACT FROM AUTHOR]

Flocculation is an integral part for cohesive sediment transport processes as it will further influence other processes such as settling, deposition as well as erosion processes. To understand the impacts of flocculation on entrainment process of fluid mud with different salinities, a series of entrainment and sedimentation experiments were conducted. Entrainment experiments were conducted under constant hydrodynamic conditions driven by a shear ring on the top of an annular flume. While the sedimentation experiments were conducted within cylinders with different diameters. Results show that fluid mud samples with different salinities can form different distributions of sediment concentration in the vertical direction, which will significantly influence the entrainment rate of fluid mud. Results also show that entrainment rate of fluid mud with higher salinity (E18) is smaller than that of fluid mud with lower salinity (E4) in the upper layer of fluid mud. Sedimentation tests show that the settling rate of fluid mud sample with higher salinity is enhanced and the gelling concentration is reached at a lower sediment concentration. These two mechanisms cause the different distributions of sediment concentration for fluid mud under different flocculation states. Accordingly, the mud characteristics such as density, viscosity, yield strength, buoyancy effects and eventually the entrainment rate vary with different fluid mud samples (the initial sediment concentrations are the same). An effort has also been made to predict the entrainment rate with existing equation. The good agreement between from equation and experimental results further demonstrates that the flocculation process should be considered when calculating the entrainment rate, as accurate prediction of the entrainment rate of fluid mud requires the details of sediment concentration and rheological properties of fluid mud in the vertical direction. • Entrainment and sedimentation tests were conducted in this study. • The flocculation effects will enhance the settling of fluid mud layer. • Fluid mud with higher salinity reaches gelling point at low concentration. • Flocculation effects make the sediment distributed uniformly in the mud layer. • Vertical structure has to be considered to get realistic entrainment rate. [ABSTRACT FROM AUTHOR]

[Display omitted] The commercialization of lithium–sulfur (Li–S) batteries is challenging, owing to factors like the poor conductivity of S, the 'shuttle effect', and the slow reaction kinetics. To address these challenges, MoP quantum dots were decorated on hollow carbon spheres (MoPQDs/C) in this study and used as an efficient lithium polysulfides (LiPSs) adsorbents and catalysts. In this approach polysulfides are effectively trapped through strong chemisorption and physical adsorption while simultaneously facilitating LiPSs conversion by enhancing the reaction kinetics. MXene serves as a flexible physical barrier (MoPQDs/C@MXene), further enhancing the confinement of LiPSs. Moreover, both materials are conductive, significantly facilitating electron and charge transfer. Additionally, the flexible MoPQDs/C@MXene–S electrode offers a large specific surface area for sulfur loading and withstand volume expansion during electrochemical processes. As a result, the MoPQDs/C@MXene–S electrode exhibits excellent long-term cyclability and maintains a robust specific capacity of 992 mA h g−1 even after 800cycles at a rate of 1.0C (1C = 1675 mA g−1), with a minimal capacity decay rate of 0.034 % per cycle. This work proposes an efficient strategy to fabricate highly efficient electrocatalysts for advanced Li–S batteries. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is one of the most common types of cancer worldwide, and there is currently no effective therapeutic strategy in clinical practice. Gene therapy has great potential for decreasing tumor-induced mortality but has been clinically limited because of the lack of tumor-specific targets and insufficient gene transfer. The study of targeted transport of therapeutic genes in HCC treatment seems to be very important. In this study, we evaluated a gene therapy approach targeting HCC using the herpes simplex virus thymidine kinase/ganciclovir (HSVtk/GCV) suicide gene system in HCC cell lines and in an in vivo human HCC xenograft mouse model. GP73-modified liposomes targeted gene delivery to the tumor tissue, and the survivin promoter drove HSVtk expression in the HCC cells. Our results showed that the survivin promoter was specifically activated in tumor cells and HSVtk was expressed selectively in tumor cells. Combined with GCV treatment, HSVtk expression resulted in suppression of HCC cell proliferation via enhancing apoptosis. Moreover, tail vein injection of GP73-HSVtk significantly suppressed the growth of xenograft tumors through an apoptosis-dependent pathway and extended the survival of tumor-bearing mice without damaging the mice liver functions. Taken together, this study demonstrates an effective cancer-specific gene therapy strategy using the herpes simplex virus thymidine kinase/ganciclovir (HSVtk/GCV) suicide gene system for HCC that can be further developed for future clinical trials. [ABSTRACT FROM AUTHOR]