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The current proliferation of mobile robots spans ecological monitoring, warehouse management and extreme environment exploration, to an individual consumer’s home1–4. This expanding frontier of applications requires robots to transit multiple environments, a substantial challenge that traditional robot design strategies have not effectively addressed5,6. For example, biomimetic design—copying an animal’s morphology, propulsion mechanism and gait—constitutes one approach, but it loses the benefits of engineered materials and mechanisms that can be exploited to surpass animal performance7,8. Other approaches add a unique propulsive mechanism for each environment to the same robot body, which can result in energy-inefficient designs9–11. Overall, predominant robot design strategies favour immutable structures and behaviours, resulting in systems incapable of specializing across environments12,13. Here, to achieve specialized multi-environment locomotion through terrestrial, aquatic and the in-between transition zones, we implemented ‘adaptive morphogenesis’, a design strategy in which adaptive robot morphology and behaviours are realized through unified structural and actuation systems. Taking inspiration from terrestrial and aquatic turtles, we built a robot that fuses traditional rigid components and soft materials to radically augment the shape of its limbs and shift its gaits for multi-environment locomotion. The interplay of gait, limb shape and the environmental medium revealed vital parameters that govern the robot’s cost of transport. The results attest that adaptive morphogenesis is a powerful method to enhance the efficiency of mobile robots encountering unstructured, changing environments.

Allelochemicals represent a class of natural products released by plants as root, leaf, and fruit exudates that interfere with the growth and survival of neighboring plants. Understanding how allelochemicals function to regulate plant responses may provide valuable new approaches to better control plant function. One such allelochemical, Myrigalone A (MyA) produced by Myrica gale, inhibits seed germination and seedling growth through an unknown mechanism. Here, we investigate MyA using the tractable model Dictyostelium discoideumand reveal that its activity depends on the conserved homolog of the plant ethylene synthesis protein 1-aminocyclopropane-1-carboxylic acid oxidase (ACO). Furthermore, in silicomodeling predicts the direct binding of MyA to ACO within the catalytic pocket. In D. discoideum, ablation of ACOmimics the MyA-dependent developmental delay, which is partially restored by exogenous ethylene, and MyA reduces ethylene production. In Arabidopsis thaliana, MyA treatment delays seed germination, and this effect is rescued by exogenous ethylene. It also mimics the effect of established ACO inhibitors on root and hypocotyl extension, blocks ethylene-dependent root hair production, and reduces ethylene production. Finally, in silicobinding analyses identify a range of highly potent ethylene inhibitors that block ethylene-dependent response and reduce ethylene production in Arabidopsis. Thus, we demonstrate a molecular mechanism by which the allelochemical MyA reduces ethylene biosynthesis and identify a range of ultrapotent inhibitors of ethylene-regulated responses.

Variable stiffness materials bridge the desirable qualities of soft and rigid robotic components, forming the basis of new machines that contextually adapt their structural properties. Recent developments have led to the creation of jamming materials: Collections of media that undergo pressure-dependent kinematic and frictional interactions to radically, rapidly, and reversibly change in stiffness. Among the types of jamming, laminar jamming harnesses an ensemble of sheets for stiffness changes. Most implementations of laminar jamming employ unaltered, continuous sheets, though the vast design space of mechanical anisotropy programmed via structured cuts invites a new jamming paradigm: kirigami laminar jamming. Through analytical, experimental, and numerical studies, we show how intentional topological augmentation of laminar jamming sheets through shell, void, and cut geometric primitives can elicit bespoke mechanical responses. In particular, we optimize jamming specimens to enhance the jammed to unjammed flexural stiffness ratio across a range of deflections, which unlocks new move-and-hold capabilities. We also demonstrate pressure-induced shape morphing and both sharp-edged and doubly-curved surface matching with kirigami patterns. Results hold broad significance for robotics, morphing structures, and the systematic design of variable stiffness materials.

Dual-functional electrocatalysts have recently been reported to improve the conversion and storage of energy generated from overall water splitting in alkaline electrolytes. Herein, for the first time, a shape-controlled synthesis of starfish-like Co–Ni–S nanosheets on three-dimensional (3D) hierarchically porous nickel foams (Co–Ni–S/NF) via a one-step hydrothermal method was developed. The influence of reaction time on the nanosheet structure and properties was intensively studied. After 11 h reaction, the Co–Ni–S/NF-11 sample displays the most regular structure of nanosheets and the most outstanding electrochemical properties. As to water splitting, hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) required overpotentials of 284.3 and 296 mV, respectively, to provide a current density of 100 mA cm–2. The marvelous electrochemical performance can be attributed to the conductive networks of 3D layered porous nickel skeletons that are highly interconnected, which provided a large specific area and highly active sites. To further enhance the electrochemical performances of the electrocatalyst, the influence of the doping of the P element was also studied. The results proved that the P-doped Co–Ni–S/NF maintains the starfish structure and demonstrates outstanding properties, providing a current density of 100 mA cm–2with only 187.4 and 292.2 mV overpotentials for HER and OER, respectively. It exhibited far more excellent properties than reported dual-functional electrocatalysts. Additionally, when used as an overall water-splitting catalyst, P–Co–Ni–S/NF can provide a 10 mA cm–2current density at a given cell voltage of 1.60 V in 1 M KOH, which is competitive to the best-known electrocatalysts, with high long-term stability.

High-performance active materials for energy-storage and energy-conversion applications require a novel class of electrodes: ones with a structure conducive to conductivity, large specific surface area, high porosity, and mechanical robustness. Herein, we report the design and fabrication of a new ternary hybrid aerogel. The process entails an in situ assembly of 2D WSe2nanosheets and NiFe-LDH nanosheets on a 3D N,S-codoped graphene framework, accomplished by a facile hydrothermal method and electrostatic self-assembly technology. The obtained nanocomposite architecture maximizes synergistic effects among its three 2D-layer components. To assess the performance of this hybrid material, we deployed it as an advanced electrode in overall water splitting and in a supercapacitor. Results in both scenarios attest to its excellent electrochemical properties. Specifically, serving as a catalyst in an oxygen evolution reaction, our nanocomposite requires overpotentials of 1.48 and 1.59 V to obtain current densities of 10 and 100 mA cm–2, respectively. The hybrid material also efficiently electrocatalyzes hydrogen evolution reactions in base solution, necessitating overpotentials of −50 and −237 mV for current densities of 1.0 and 100 mA cm–2, respectively. The 3D hybrid, when applied to a symmetric supercapacitor device, achieves 125.6 F g–1capacitance at 1 A g–1current density. In summary, our study elucidates a new strategy to maximize efficiency via synergetic effects that is likely applicable to other 2D materials.

Synthesis of highly efficient and robust catalysts with earth-abundant resources for overall water splitting is essential for large-scale energy conversion processes. Herein, a series of highly active and inexpensive Co–Ni–P films were fabricated by a one-step constant current density electrodeposition method. These films were demonstrated to be efficient bifunctional catalysts for both H2and O2evolution reactions (HER and OER), while deposition time was deemed to be the crucial factor governing electrochemical performance. At the optimal deposition time, the obtained Co–Ni–P-2 catalyst performed remarkably for both HER and OER in alkaline media. In particular, it requires −103 mV overpotential for HER and 340 mV for OER to achieve the current density of 10 mA cm–2, with corresponding Tafel slopes of 33 and 67 mV dec–1. Moreover, it outperforms the Pt/C//RuO2catalyst and only needs −160 mV (430 mV) overpotential for HER (OER) to achieve 200 mA cm–2current density. Co–Ni–P electrodes were also conducted for the proof-of-concept exercise, which were proved to be flexible, stable, and efficient, further opening a new avenue for rapid synthesis of efficient, flexible catalysts for renewable energy resources.

Direct liquid phase exfoliation (LPE) is generally regarded as an effective and efficient methodology for preparing single- to few-layered nanosheets on a large scale. Based on a previous finding that the polar and dispersive components of surface tension can be used as critical parameters for screening suitable solvents for LPE, in this study, we conducted in-depth research on direct LPE of two-dimensional (2D) materials by the extensive LPE of a series of 2D materials and the thorough comparison of their surfaces properties and LPE efficiencies. We rationally developed the surface tension component matching (STCM) theory, and in nature, its key point lies in the close ratio of polar to dispersive components (P/D) between the solvents and the aimed 2D materials. To this end, the surface tension components ratio is demonstrated to be an effective parameter for screening LPE solvents. In addition to the optimization of the LPE process for these 2D materials, this work has further greatly enlarged the comprehensive library for the solvent and 2D material matching pairs based on the improved STCM theory.

Herein, we describe the preparation and testing of Co-doped FeSe2hybridized with graphene (Fe1–xCoxSe2/RGO), a high-active yet stable electrocatalyst for hydrogen evolution reactions (HERs) in acidic solutions. First, we systematically analyze the composition and morphology of Fe1–xCoxSe2/RGO and attribute its excellent electrochemical performance to its unique architecturea base of highly conductive graphene with fully exposed active edges that enhances conductivity and facilitates ion/electron transfer. Our experimental measurements indicate elevated HER activity with a moderate overpotential of ∼166 mV at a hydrogen production current density of 10 mA cm–2, a small Tafel slope of ∼36 mV dec–1, and long cycling lifespan more than 20 h. The promising results, in addition to the fact that Fe1–xCoxSe2/RGO is a high-performance, precious-metal-free electrocatalyst, pave the way for exciting opportunities in renewable hydrogen production applications.

Precise control of the electronic surface states of two-dimensional (2D) materials could improve their versatility and widen their applicability in electronics and sensing. To this end, chemical surface functionalization has been used to adjust the electronic properties of 2D materials. So far, however, chemical functionalization has relied on lattice defects and physisorption methods that inevitably modify the topological characteristics of the atomic layers. Here we make use of the lone pair electrons found in most of 2D metal chalcogenides and report a functionalization method via a Lewis acid–base reaction that does not alter the host structure. Atomic layers of n-type InSe react with Ti4+to form planar p-type [Ti4+n(InSe)] coordination complexes. Using this strategy, we fabricate planar p–n junctions on 2D InSe with improved rectification and photovoltaic properties, without requiring heterostructure growth procedures or device fabrication processes. We also show that this functionalization approach works with other Lewis acids (such as B3+, Al3+and Sn4+) and can be applied to other 2D materials (for example MoS2, MoSe2). Finally, we show that it is possible to use Lewis acid–base chemistry as a bridge to connect molecules to 2D atomic layers and fabricate a proof-of-principle dye-sensitized photosensing device.

One university's failure to adhere to AAUP-recommended standards and principles offers broader lessons. This would have been a serious matter, not least because the UE faculty manual states that the university "adheres to" certain AAUP guidelines, including those set forth in the I Recommended Institutional Regulations i . Yet, while March 5 was after the end date for the faculty discussion period, faculty members considering enrolling in the voluntary separation program could not have known the date on which the university would announce its final decisions regarding program closures. Had the senior administration pushed through the proposed program closures and then terminated faculty appointments as a result of those closures, the terminations would clearly have violated AAUP standards. [Extracted from the article]

Reports on the technological advancements made in the telephone industry. Dependence of test information relay on the high capacity of optical-fiber networks; Compatibility in design of assymetric digital subscriber line (ADSL) with telephone services; Difficulty in achieving standard modulation speed.

Focuses on the economic outlook for the city of Manchester, New Hampshire. Importance of being an optimist; Evidence of progress within the city.