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Currently, uncontrolled bleeding remains a serious problem in emergency, surgical and battlefield environments. Despite the specific properties of available hemostatic agents, sealants, and adhesives, effective hemostasis under wet and dynamic conditions remains a challenge. In recent years, polymeric hydrogels with excellent hemostatic properties have received much attention because of their adjustable mechanical properties, high porosity, and biocompatibility. In this review, to investigate the role of hydrogels in hemostasis, the mechanisms of hydrogel hemostasis and adhesion are firstly elucidated, the adhesion design strategies of hemostatic hydrogels in wet environments are briefly introduced, and then, based on a comprehensive literature review, the studies and in vivo applications of wet-adhesive hemostatic hydrogels in different environments are summarized, and the improvement directions of such hydrogels in future studies are proposed. [ABSTRACT FROM AUTHOR]

Exogenous antioxidant materials mimicking endogenous antioxidant systems are commonly used for the treatment of oxidative stress-induced injuries. Thus, artificial enzymes have emerged as promising candidates for balancing and treating the dysregulation of redox homeostasis in vivo. Herein, a one-pot hydrothermal strategy for the facile preparation of MoSe2-polyvinylpyrrolidone (PVP) nanoparticles (NPs) is reported. The synthesized NPs were biodegradable due to their exposure to oxygen and exhibited high stability. Moreover, they effectively mimicked various naturally occurring enzymes (including catalase, superoxide dismutase, peroxidase, and glutathione peroxidase) and scavenged free radicals, such as 3-ethylbenzothiazoline-6-sulfonic acid, ·OH, ·O2−, and 1,1-diphenyl-2-picrylhydrazyl radical. Further apoptosis detection studies revealed that MoSe2-PVP NPs significantly increased the cell survival probability in H2O2 in a concentration-dependent manner. The cytoprotective effect of MoSe2-PVP NPs was explored for an animal model of acute pancreatitis, which confirmed its remarkable therapeutic efficacy. Owing to the biodegradable and biocompatible nature of MoSe2-PVP NPs, the findings of this work can stimulate the development of other artificial nanoenzymes for antioxidant therapies. [ABSTRACT FROM AUTHOR]

Reconfigurable software is highly desired for automated machine tool control systems for low-cost products and short time to market. In this paper, we propose a software architecture based on a combination of object-oriented models and executable formal specifications. In this architecture, the machine control software is viewed as an integration of a set of reusable software components, each modeled with a set of event-based external interfaces for functional definitions, a control logic driver for execution of behavioral specifications, and a set of service protocols for platform adaptation. The behaviors of the entire software can be viewed as an integration of behaviors of components and their integration, and can be specified in a Control Plan specification language, which is based on Nested Finite State Machines, independently of the component implementations. Separation of structural specification from behavioral specification enables the controller software structure to be reconfigured independently of application, and software behavior to be reconfigured independently of controller software structure. When the system needs reconfiguration due to changes in either application requirements or the execution platform, the software with our architecture can then be reconfigured by changing reusable components and their interactions in structure for functional capability, and by changing the Control Plan program for behavior. Both types of reconfiguration can be done at the executable code level after the software is implemented. The proposed architecture also supports reconfigurability to facilitate heterogeneous implementations and vendor-neutral products. Our evaluation based on current software construction practices for both laboratory machine tools and an industry machining system has shown that the goals of higher reconfigurability and lower development and maintenance costs are achieved with the control software constructed using the proposed architecture. Index Terms--Controller architecture, machine control systems, reconfigurable software, software models.

Hierarchical nanosheet-based MoS2–NiS nanotubes coated with N-doped carbon (MNS-HNT@NC) composites were fabricated using a template-assisted hydrothermal and post-sulfidation strategy. The composite, with a tube-like structure, is mainly constructed by ultrathin MoS2–NiS nanosheets. Such hierarchical nanosheet-based nanotubes possess high surface-to-volume ratios, which can release mechanical stress during Na ion insertion/extraction and shorten the pathways for Na ion/electron transport. Furthermore, the internal void space in the nanotube can effectively accommodate the large volume change of the electrode, thereby alleviating structural collapse of the electrode. On the other hand, abundant lattice defects and the internal electric field induced by the heterostructure of MoS2 and NiS boost the Na ion intercalation kinetics. In addition, the MoS2 and NiS nanocrystals uniformly dispersed in the composite can act as mutual spacers, thereby avoiding aggregation during cycling. The MNS-HNT further coated with N-doped carbon can reduce contact resistance and restrict the large volume change, preventing electrode pulverization. Benefiting from these advantages and using an ether-based electrolyte, MNS-HNT@NC, as anode for SIBs, delivers a considerable specific capacity (707 mA h g−1 at 0.1 A g−1), high initial coulombic efficiency of 94%, stable long-term cycling stability (391 mA h g−1 maintained after 700 cycles at 2 A g−1) and superior rate performance (342 mA h g−1 at 10 A g−1). [ABSTRACT FROM AUTHOR]

Developing economical, efficient and stable bifunctional catalysts for hydrogen production from seawater is of great significance for hydrogen utilization. Herein, sulfur doped iron oxide nanosheet arrays supported on nickel foam (FeOx–Ni3S2@NF) are prepared by a one-pot solvothermal reaction. Owing to the high intrinsic activity of FeOx–Ni3S2, the large catalytic specific surface area of nanosheet arrays and the fast charge transportation capability achieved by the self-supporting configuration, the FeOx–Ni3S2@NF electrode delivers excellent catalytic performance in alkaline simulated seawater (1 M KOH + 0.5 M NaCl). Impressively, a low overpotential of 120 mV at 50 mA cm−2 with a Tafel slope of 57 mV dec−1 for the hydrogen evolution reaction and an overpotential of 470 mV at 200 mA cm−2 with a Tafel slope of 62 mV dec−1 for the oxygen evolution reaction are achieved. More importantly, the voltage is only 1.5 V at 50 mA cm−2 for continuous overall water splitting for 100 h at 200 mA cm−2 with negligible decay in alkaline simulated seawater with almost 100% Faraday efficiency. This work provides a simple and universal strategy to prepare highly efficient bifunctional catalytic materials, promoting the development of Earth-abundant materials to catalyse seawater splitting to produce high-purity hydrogen. [ABSTRACT FROM AUTHOR]