Engineering

  • Article
    | Open Access

    The ever-growing need for highly functional, compact, and integrated microfluidic devices often incurs lengthy and expensive manufacturing processes. Here, authors introduce a generalized 3D printing process that enables fast parallel fabrication of miniaturized, high resolution 3D components.

    • Jose L. Sanchez Noriega
    • , Nicholas A. Chartrand
    •  & Gregory P. Nordin
  • Article
    | Open Access

    Wear-resistant metals have long been a pursuit of reducing wear-related energy and material loss. Here the authors present the ‘reactive wear protection’ strategy via friction-induced in situ formation of strong and deformable oxide nanocomposites on a surface.

    • Chang Liu
    • , Zhiming Li
    •  & Dierk Raabe
  • Article
    | Open Access

    The strength in BCC high-entropy alloys is associated with the type of mobile dislocations. Here the authors demonstrate by means of an ample array of experimental techniques that edge dislocations can control the strength of BCC high-entropy alloys.

    • Chanho Lee
    • , Francesco Maresca
    •  & W. A. Curtin
  • Article
    | Open Access

    Dual-energy X-ray absorptiometry and the Fracture Risk Assessment Tool are recommended tools for osteoporotic fracture risk evaluation, but are underutilized. Here, the authors present an opportunistic tool to identify fractures, predict bone mineral density and evaluate fracture risk using plain pelvis and lumbar spine radiographs.

    • Chen-I Hsieh
    • , Kang Zheng
    •  & Chang-Fu Kuo
  • Article
    | Open Access

    The development of fast and dynamic topological photonic platforms is an ongoing challenge. Here, the authors demonstrate a reprogrammable plasmonic topological insulator in which ultrafast electric switches allow for nanosecond-level switching time between different configurations.

    • Jian Wei You
    • , Qian Ma
    •  & Tie Jun Cui
  • Article
    | Open Access

    Deep eutectic solvents (DES) are intriguing green reaction media for biomass processing, however, undesired lignin condensation is a typical drawback. Here the authors develop a tunable ternary DES system that allows for stabilization of reactive intermediates for efficient lignocellulose fractionation.

    • Yongzhuang Liu
    • , Noemi Deak
    •  & Katalin Barta
  • Article
    | Open Access

    Through development of non-fullerene acceptors, OPVs have reached efficiencies of 18%, yet the inadequate operational lifetime still poses a challenge for the commercialisation. Here, the authors investigate the origin of instability of NFA solar cells, and propose some strategies to mitigate this issue.

    • Yongxi Li
    • , Xiaheng Huang
    •  & Stephen R. Forrest
  • Article
    | Open Access

    The long-term cycling of Li-S batteries depends on the polysulfides shuttling regulation. Here, the authors present a saccharide-based binder system to control the polysulfides migration and improve the cycle life of a Li-S pouch cell.

    • Yingyi Huang
    • , Mahdokht Shaibani
    •  & Mainak Majumder
  • Article
    | Open Access

    Electron beam lithography (EBL) is renowned to provide fabrication resolution in the deep nanometer scale but their incapability of arbitrary 3D nanofabrication poses a major limitation to the technique. Here, the authors demonstrate a manufacturing technique of functional 3d nanostructures at a resolution of sub-15 nm using voltage-regulated 3d EBL.

    • Nan Qin
    • , Zhi-Gang Qian
    •  & Tiger H. Tao
  • Article
    | Open Access

    Previous approaches to derive embryoids either lack physiological morphology and signaling interactions, or are unconducive to model post-gastrulation development. Here the authors use a high-throughput approach to induce mouse embryonic stem cells into epiblast-like aggregates, which are then co-cultured with mouse trophoblast stem cell aggregates, to yield embryoids with axial morphogenesis and anterior development.

    • Mehmet U. Girgin
    • , Nicolas Broguiere
    •  & Matthias P. Lutolf
  • Article
    | Open Access

    Immune checkpoint blockade antibodies have promising clinical applications, but suffer from severe toxicities and moderate response rates. Here the authors present an electrode-embedded, implantable optical fiber device with both local delivery and tumor impedance measurement capabilities to safely elicit durable anti-tumor immunity.

    • Ai Lin Chin
    • , Shan Jiang
    •  & Rong Tong
  • Article
    | Open Access

    Protein delivery with cell-penetrating peptides suffers from ineffective endosomal escape and low tolerance in serum, thereby limiting treatment success. Here the authors present an intracellular protein delivery system and demonstrate efficient delivery in vitro and therapeutic efficacy in a liver failure model in vivo.

    • Siyuan Yu
    • , Han Yang
    •  & Ningshao Xia
  • Article
    | Open Access

    Uninterrupted monitoring of pressure and temperature at skin interfaces can help to minimize the potential for pressure injuries in hospitalized or bedridden patients. Here, the authors introduce a soft, skin-mountable sensor that can continuously provide readings via antennas mounted under bedding, and demonstrate the functionality and robustness of the devices on patients.

    • Yong Suk Oh
    • , Jae-Hwan Kim
    •  & John A. Rogers
  • Article
    | Open Access

    Direct bioprinting in vivo has the potential to enable new clinical strategies but is currently limited by printing techniques. Here, the authors report on the development of a ferromagnetic soft catheter for magnetic computer controlled minimally invasive bioprinting and demonstrate the printing potential in vivo.

    • Cheng Zhou
    • , Youzhou Yang
    •  & Jianfeng Zang
  • Article
    | Open Access

    The authors create synthetic dimensions in acoustic crystals composed of cavity arrays, strongly coupled through modulated channels. They provide evidence for 1D and 2D dynamic topological pumping, and show that the higher-order topological sound transport is robust against the geometrical imperfections.

    • Hui Chen
    • , Hongkuan Zhang
    •  & Guoliang Huang
  • Article
    | Open Access

    Dissipative self-assembly, which requires a continuous supply of fuel to maintain the assembled states far from equilibrium, is the foundation of biological systems but it remains a challenge to introduce light as fuel into artificial dissipative self-assemblies. Here, the authors report an artificial dissipative self-assembly system that is constructed from light-induced amphiphiles.

    • Xu-Man Chen
    • , Xiao-Fang Hou
    •  & Quan Li
  • Article
    | Open Access

    Though shape-changing devices are promising for future haptic displays, existing designs fail to provide smooth surfaces for the user during tactile exploration. Here, the authors utilize flexible auxetic structures to realize shape displays with smooth surfaces and different Gaussian curvatures.

    • Binghao Wang
    • , Wei Huang
    •  & Antonio Facchetti
  • Article
    | Open Access

    Current designs of thermal switches are limited by a lack of continuous tunability, low switching ratio, low speed, and not being scalable. Here the authors report a continuously tunable, wide-range, fast, and cost effective thermal switching approach that is demonstrated using compressible graphene composite foams.

    • Tingting Du
    • , Zixin Xiong
    •  & Xiulin Ruan
  • Article
    | Open Access

    Refractory high entropy alloys hold big promise for elevated-temperature applications. Here the authors investigate the influence of short-range order on the mobility of dislocations in high-entropy alloys by large-scale molecular dynamics simulation based on a machine-learning interatomic potential.

    • Sheng Yin
    • , Yunxing Zuo
    •  & Robert O. Ritchie
  • Article
    | Open Access

    Though bound states in the continuum (BICs) in acoustic systems are attractive for acoustic resonators design, acoustic BICs typically show low Q-factor. Here, the authors report a high performance open acoustic resonator that supports symmetry-protected, Friedrich-Wintgen and mirror symmetry-induced BICs.

    • Lujun Huang
    • , Yan Kei Chiang
    •  & Andrey E. Miroshnichenko
  • Article
    | Open Access

    Realizing an artificial camouflage device with a high spatial resolution by adapting to the surrounding environment in real-time is a challenging task, mainly associated with device fabrication and integration with sensor and control circuits. To overcome these limitations, the authors utilize thermochromic liquid crystal ink that reacts to the feedback control system of the vertically stacked silver nanowire heater.

    • Hyeonseok Kim
    • , Joonhwa Choi
    •  & Seung Hwan Ko
  • Article
    | Open Access

    Though shape-changing devices are promising for future haptic displays, existing designs fail to provide smooth surfaces for the user during tactile exploration. Here, the authors utilize flexible auxetic structures to realize shape displays with smooth surfaces and different Gaussian curvatures.

    • Anthony Steed
    • , Eyal Ofek
    •  & Mar Gonzalez-Franco
  • Article
    | Open Access

    Sensing mechanical signals is an important aspect for a range of applications of E-skins. Here, the authors report on the creation of deforming iontronic sensing structures which can use ionic transport through tissues to create a simple and sensitive E-skin for sensing touch, pulse and motion demonstrating application.

    • Pang Zhu
    • , Huifeng Du
    •  & Chuan Fei Guo
  • Article
    | Open Access

    Ferroelectric liquid crystals (FLCs) have faster optical response times than nematic crystals, but they are also less robust to external shock. Here the authors develop an FLC geometry that reduces the sensitivity to external disruption through self-healing, making them more stable for applications.

    • Peter J. M. Wyatt
    • , James Bailey
    •  & J. Cliff Jones
  • Article
    | Open Access

    Developing effective treatments for noncompressible hemorrhages remains a challenge. Here the authors engineer alkylated chitosan sponges with highly interconnective microchannels and demonstrate anti-infective activity, as well as higher pro-coagulant, hemostatic and wound healing capacities compared to clinically-used materials in rat and pig liver models.

    • Xinchen Du
    • , Le Wu
    •  & Meifeng Zhu
  • Article
    | Open Access

    Despite advances on fabrication of stretchable interconnects, realizing functional electronics with integrated solid-state technology (SST) remains a challenge. Here, the authors report a reversible Pol-Gel transition method for fabrication of liquid-metal based, chip-integrated, printed stretchable circuits.

    • Pedro Alhais Lopes
    • , Bruno C. Santos
    •  & Mahmoud Tavakoli
  • Article
    | Open Access

    Conventional DC-DC converters rely on switching operations and energy storing components which face both noise and scaling difficulties. Here, the authors present an alternative design for a DC-to-DC converter based on closely coupled LEDs and photovoltaic cells, which exhibits high efficiency, low noise, and miniaturizability.

    • Bo Zhao
    • , Sid Assawaworrarit
    •  & Shanhui Fan
  • Article
    | Open Access

    A semiconductor thermionic device, which utilises thermally excited electrons, is considered as an alternative in solar conversion technology, yet its working mechanism is not clear. Here, the authors reveal that whether such a device operates in the photon enhanced or purely thermionic mode, greatly depends on the material properties and device physics.

    • Ehsanur Rahman
    •  & Alireza Nojeh
  • Article
    | Open Access

    Polycrystal-inspired architected materials are found to be high strength and damage tolerant. Here, the authors conduct in-depth work to unravel the mechanism responsible for the hardening phenomenon, in particular the role of polygrain-like boundary in the post-yield shear band activities.

    • Chen Liu
    • , Jedsada Lertthanasarn
    •  & Minh-Son Pham
  • Article
    | Open Access

    Wear reduction in diamond-like carbon interacting with ZDDP-additivated oils is essential for current automotive applications. Here, the authors present an atomic-scale study revealing that this can be achieved by tailoring diamond-like carbon’s stiffness, surface nano-topography, and hydrogen content.

    • Valentin R. Salinas Ruiz
    • , Takuya Kuwahara
    •  & Maria-Isabel de Barros Bouchet
  • Article
    | Open Access

    Imaging rates in single-pixel imaging has been limited by the dependence on configurable spatial light modulators. Here, the authors use cyclic Hadamard patterns coded onto a spinning mask to demonstrate dynamic imaging with rates up to 72 frames per second and real time reconstruction capabilities.

    • Evgeny Hahamovich
    • , Sagi Monin
    •  & Amir Rosenthal
  • Article
    | Open Access

    Near-field thermophotovoltaic holds the potential for achieving high-power density and energy conversion efficiency by utilizing evanescent modes of heat transfer, yet the performance still lags behind the far-field counterpart. Here, the authors combine thermally robust planar emitter with InGaAs PV to push the limit of near-field device further.

    • Rohith Mittapally
    • , Byungjun Lee
    •  & Edgar Meyhofer
  • Article
    | Open Access

    Lead toxicity poses a big hurdle for the commercialization of perovskite optoelectronics, hence reducing the environmental impact holds the answer for its future application. To tackle this challenge, the authors utilize germanium to reduce the lead content, enabling highly luminescent eco-friendly compound for LEDs.

    • Dexin Yang
    • , Guoling Zhang
    •  & Dawei Di
  • Article
    | Open Access

    Current methods to estimate energy expenditure are either infeasible for everyday use or associated with significant errors. Here the authors present a Wearable System using inertial measurement units worn on the shank and thigh that estimates metabolic energy expenditure in real-time during common steady-state and time-varying activities.

    • Patrick Slade
    • , Mykel J. Kochenderfer
    •  & Steven H. Collins
  • Article
    | Open Access

    Recurrent spiking neural networks have garnered interest due to their energy efficiency; however, they suffer from lower accuracy compared to conventional neural networks. Here, the authors present an alternative neuron model and its efficient hardware implementation, demonstrating high classification accuracy across a range of datasets.

    • Ahmed Shaban
    • , Sai Sukruth Bezugam
    •  & Manan Suri
  • Article
    | Open Access

    Estimating velocities in gas liquid flows is of importance in many engineering applications. Hohermuth et al. show that previous bubble velocities obtained from intrusive probes have been underestimated and provide a correction scheme for more accurate velocity measurements.

    • B. Hohermuth
    • , M. Kramer
    •  & D. Valero
  • Article
    | Open Access

    Authors demonstrate Si-based MIS photoanodes using Al thin-film reactions to create localized conduction paths through the insulator and Ni electrodeposition to form metal catalyst islands. These approaches yielded low onset potential, high saturation current density, and excellent stability.

    • Soonil Lee
    • , Li Ji
    •  & Edward T. Yu
  • Article
    | Open Access

    The current biorefineries yield lignin with inadequate fractionation for bioconversion, yet substantial changes of these biorefinery designs could jeopardize carbohydrate efficiency and increase capital costs. Here the authors resolve the dilemma by designing ‘plug-in processes of lignin’ to enable economic waste valorization.

    • Zhi-Hua Liu
    • , Naijia Hao
    •  & Joshua S. Yuan
  • Article
    | Open Access

    Irreversible electroporation (IRE), a soft-tissue ablation technique used for tumour ablation, has been suggested to promote systemic immune responses. Here the authors show that IRE, followed by anti-CTLA-4 blockade, elicits the expansion of tumor antigen-specific CD8+ T cells and is associated with tissue residency and improved anti-tumor immune response in a preclinical model of prostate cancer.

    • Brandon J. Burbach
    • , Stephen D. O’Flanagan
    •  & Yoji Shimizu
  • Article
    | Open Access

    In-silico trials rely on virtual populations and interventions simulated using patient-specific models and may offer a solution to lower costs. Here, the authors present the flow diverter performance assessment in-silico trial, which models the treatment of intracranial aneurysms with a flow-diverting stent.

    • Ali Sarrami-Foroushani
    • , Toni Lassila
    •  & Alejandro F. Frangi
  • Article
    | Open Access

    Postsurgical adhesions are a problem during routine cardiothoracic procedures. Here, the authors report on a catechol functionalised hydrogel as an anti-adhesion material with improved retention on the heart which is biocompatible and biodegradable with minimal swelling, demonstrating application in vivo.

    • Masaki Fujita
    • , Gina M. Policastro
    •  & Karen L. Christman
  • Article
    | Open Access

    Printed biosensors are important for health monitoring and research purposes. Here, the authors report on the development of a soft poroelastic silicone based sensor which can be easily printed and is resistant to mechanical strain hysteresis, allowing for more accurate electrophysiology readings and imaging.

    • Bongjoong Kim
    • , Arvin H. Soepriatna
    •  & Chi Hwan Lee