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Invadopodia are dynamic actin-rich membrane protrusions that have been implicated in cancer cell invasion and metastasis. In addition, invasiveness of cancer cells is strongly correlated with invadopodia formation, which are observed during extravasation and colonization of metastatic cancer cells at secondary sites. However, quantitative understanding of the interaction of invadopodia with extracellular matrix (ECM) is lacking, and how invadopodia protrusion speed is associated with the frequency of protrusion-retraction cycles remains unknown. Here, we present a computational framework for the characterization of invadopodia protrusions which allows two way interactions between intracellular branched actin network and ECM fibers network. We have applied this approach to predicting the invasiveness of cancer cells by computationally knocking out actin-crosslinking molecules, such as α-actinin, filamin and fascin. The resulting simulations reveal distinct invadopodia dynamics with cycles of protrusion and retraction. Specifically, we found that (1) increasing accumulation of MT1-MMP at tips of invadopodia as the duration of protrusive phase is increased, and (2) the movement of nucleus toward the leading edge of the cell becomes unstable as duration of the retractile phase (or myosin turnover time) is longer than 1 min. [ABSTRACT FROM AUTHOR]

A steel slit damper has been used to enhance the seismic performance of structures with several advantages. The damper can be easily manufactured at a low cost. Furthermore, it can dissipate a significant amount of seismic energy through the stable hysteretic behavior of steel. This study presents a preliminary investigation of the development of a composite steel slit damper that can respond effectively at multiple levels of seismic loading. The performance of the prototype composite steel slit damper is investigated in both experimental and analytical ways. In the experiments, the specimen shows the stable hysteretic response with sufficient ductility, where the multi-phased response is observed in the incremental-amplitude cyclic loading case. Furthermore, a nonlinear numerical analysis that combines both kinematic hardening and isotropic hardening models can reliably describe such characteristics. [ABSTRACT FROM AUTHOR]

To accelerate the discovery of materials through computations and experiments, a well-established protocol closely bridging these methods is required. We introduce a high-throughput screening protocol for the discovery of bimetallic catalysts that replace palladium (Pd), where the similarities in the electronic density of states patterns were employed as a screening descriptor. Using first-principles calculations, we screened 4350 bimetallic alloy structures and proposed eight candidates expected to have catalytic performance comparable to that of Pd. Our experiments demonstrate that four bimetallic catalysts indeed exhibit catalytic properties comparable to those of Pd. Moreover, we discover a bimetallic (Ni-Pt) catalyst that has not yet been reported for H2O2 direct synthesis. In particular, Ni61Pt39 outperforms the prototypical Pd catalyst for the chemical reaction and exhibits a 9.5-fold enhancement in cost-normalized productivity. This protocol provides an opportunity for the catalyst discovery for the replacement or reduction in the use of the platinum-group metals. [ABSTRACT FROM AUTHOR]

A surface manipulation of metal oxide-based photoelectrodes with overlaid co-catalysts has emerged as a promising strategy for boosting photoelectrochemical (PEC) water splitting activities. We demonstrate a nature molecule-mediated novel organometallic overlayer with exposed single atoms (SAs) on the surface of nanoparticulate tungsten oxide (WO 3) photoanode with a significantly boosted solar water splitting activity and its long-term durability in aqueous electrolytes with wide pH range via a spontaneous one-pot assembly of a quercetin-nickel (QNi) complex on WO 3. The QNi complex with exposed Ni SAs modified WO 3 photoanode achieves a more that 2.7-fold enhancement on photocurrent density at 1.23 V RHE in a mild condition (pH 7) and remarkable long-term durability of over 15 h. This work provides an attractive idea for efficient water splitting by utilizing a facile spontaneous assembly of organometallic overlayer with environmentally friendly materials, which is a step towards the goal of achieving green hydrogen. [Display omitted] • Assemble a nature molecule-mediated quercetin-Ni (QNi) overlayer on WO 3. • QNi/WO 3 shows high stability for PEC water splitting in wide pH range. • The exposed Ni single atoms highly improve the surface catalytic kinetics. • This quercetin-Ni complex provides an strategy for the concept of green hydrogen. [ABSTRACT FROM AUTHOR]