The advent of conductive self-healing (CSH) hydrogels, a class of novel materials mimicking human skin, may change the trajectory of the industrial process because of their potential applications in soft robots, biomimetic prostheses, and health-monitoring systems. Here, the development of a mechanically and electrically self-healing hydrogel based on physically and chemically cross-linked networks is reported. The autonomous intrinsic self-healing of the hydrogel is attained through dynamic ionic interactions between carboxylic groups of poly(acrylic acid) and ferric ions. A covalent cross-linking is used to support the mechanical structure of the hydrogel. Establishing a fair balance between the chemical and physical cross-linking networks together with the conductive nanostructure of polypyrrole networks leads to a double network hydrogel with bulk conductivity, mechanical and electrical self-healing properties (100% mechanical recovery in 2 min), ultrastretchability (1500%), and pressure sensitivity. The practical potential of CSH hydrogels is further revealed by their application in human motion detection and their 3D-printing performance.

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A double network chitosan‐based hydrogel with bulk conductivity, mechanical and electrical self‐healing properties, ultra‐stretchability and pressure sensitivity in chemical and physical crosslinking networks, together with ionic conductivity and polypyrrole networks is presented in article number https://doi.org/10.1002/adma.201700533 by Gaoxing Luo, Malcolm Xing, and co‐workers. Wirelessly connected via smart phone, this stretchable 3D‐printed sensor can monitor pulse and muscle motions.

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Transboundary water treaties are evaluated and compared using Multiple Criteria Decision Analysis (MCDA) in order to identify the most desirable treaty and suggest how existing treaties can be improved. More specifically, a flexible MCDA technique, called the Elimination Method, is employed for analyzing and comparing three multilateral treaties and one bilateral transboundary treaty according to three main criteria, which focus on each treaty's capacity in dispute avoidance and resolution. The three multilateral agreements and one bilateral treaty which are studied consist of the 1998 Rhine Convention, 1995 Mekong River Basin Agreement, 1992 United Nations Economic Commission for Europe Convention, and the 1909 Boundary Waters Treaty between Canada and the United States, respectively. The analytical results reveal limitations of these international water policies with respect to conflict resolution, and provide directions for the possible improvement in cooperation over international water resources.