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Small‐scale magnetic soft‐bodied robots based on biocompatible and biodegradable materials are essential for their potential high‐impact minimally invasive medical applications inside the human body. Therefore, a strategy for fully biodegradable untethered soft millirobots with encoded 3D magnetic anisotropy for their static or dynamic shape programming is presented. Such a robot body is comprised of a porcine extracellular matrix‐derived collagen‐based hydrogel network with embedded superparamagnetic iron oxide nanoparticles (SPIONs). 3D magnetization programming inside the hydrogel body is achieved by directionally self‐assembled SPION chains using an external permanent magnet. As a proof‐of‐concept demonstration, a hydrogel milli‐gripper that can undergo flexible and reversible shape deformations inside glycerol and biologically relevant liquid media is presented. The gripper can perform cargo grabbing, transportation by rolling, and release by controlling magnetic field inputs. These milli‐grippers can be completely degraded by the matrix metalloproteinase‐2 enzyme in physiologically relevant concentrations. Furthermore, biocompatibility tests using human umbilical cord vein endothelial cells with the degradation products of the grippers demonstrate no acute toxicity. The approach offers a facile fabrication strategy for designing biocompatible and biodegradable soft robots using nanocomposite materials with programmable 3D magnetic anisotropy toward future medical applications. [ABSTRACT FROM AUTHOR]

Biohybrid microswimmers exploit the swimming and navigation of a motile microorganism to target and deliver cargo molecules in a wide range of biomedical applications. Medical biohybrid microswimmers suffer from low manufacturing yields, which would significantly limit their potential applications. In the present study, a biohybrid design strategy is reported, where a thin and soft uniform coating layer is noncovalently assembled around a motile microorganism. Chlamydomonas reinhardtii (a single‐cell green alga) is used in the design as a biological model microorganism along with polymer–nanoparticle matrix as the synthetic component, reaching a manufacturing efficiency of ≈90%. Natural biopolymer chitosan is used as a binder to efficiently coat the cell wall of the microalgae with nanoparticles. The soft surface coating does not impair the viability and phototactic ability of the microalgae, and allows further engineering to accommodate biomedical cargo molecules. Furthermore, by conjugating the nanoparticles embedded in the thin coating with chemotherapeutic doxorubicin by a photocleavable linker, on‐demand delivery of drugs to tumor cells is reported as a proof‐of‐concept biomedical demonstration. The high‐throughput strategy can pave the way for the next‐generation generation microrobotic swarms for future medical active cargo delivery tasks. [ABSTRACT FROM AUTHOR]

News portals are a popular destination for web users. News providers are therefore interested in attaining higher visitor rates and promoting greater engagement with their content. One aspect of engagement deals with keeping users on site longer by allowing them to have enhanced click-through experiences. News portals have invested in ways to embed links within news stories but so far these links have been curated by news editors. Given the manual effort involved, the use of such links is limited to a small scale. In this article, we evaluate a system-based approach that detects newsworthy events in a news article and locates other articles related to these events. Our system does not rely on resources like Wikipedia to identify events, and it was designed to be domain independent. A rigorous evaluation, using Amazon's Mechanical Turk, was performed to assess the system-embedded links against the manually-curated ones. Our findings reveal that our system's performance is comparable with that of professional editors, and that users find the automatically generated highlights interesting and the associated articles worthy of reading. Our evaluation also provides quantitative and qualitative insights into the curation of links, from the perspective of users and professional editors. [ABSTRACT FROM AUTHOR]

A general drawback of supramolecular peptide networks is their weak mechanical properties. In order to overcome a similar challenge, mussels have adapted to a pH-dependent iron complexation strategy for adhesion and curing. This strategy also provides successful stiffening and self-healing properties. The present study is inspired by the mussel curing strategy to establish iron cross-link points in self-assembled peptide networks. The impact of peptide-iron complexation on the morphology and secondary structure of the supramolecular nanofibers is characterized by scanning electron microscopy, circular dichroism and Fourier transform infrared spectroscopy. Mechanical properties of the cross-linked network are probed by small angle oscillatory rheology and nanoindentation by atomic force microscopy. It is shown that iron complexation has no influence on self-assembly and β-sheet-driven elongation of the nanofibers. On the other hand, the organic-inorganic hybrid network of iron cross-linked nanofibers demonstrates strong mechanical properties comparable to that of covalently cross-linked network. Strikingly, iron cross-linking does not inhibit intrinsic reversibility of supramolecular peptide polymers into disassembled building blocks and the self-healing ability upon high shear load. The strategy described here could be extended to improve mechanical properties of a wide range of supramolecular polymer networks. [ABSTRACT FROM AUTHOR]

Poor retention rate, low targeting accuracy, and spontaneous transformation of stem cells present major clinical barriers to the success of therapies based on stem cell transplantation. To improve the clinical outcome, efforts should focus on the active delivery of stem cells to the target tissue site within a controlled environment, increasing survival, and fate for effective tissue regeneration. Here, a remotely steerable microrobotic cell transporter is presented with a biophysically and biochemically recapitulated stem cell niche for directing stem cells towards a pre‐destined cell lineage. The magnetically actuated double‐helical cell microtransporters of 76 µm length and 20 µm inner cavity diameter are 3D printed where biological and mechanical information regarding the stem cell niche are encoded at the single‐cell level. Cell‐loaded microtransporters are mobilized inside confined microchannels along computer‐controlled trajectories under rotating magnetic fields. The mesenchymal stem cells are shown retaining their differentiation capacities to commit to the osteogenic lineage when stimulated inside the microswimmers in vitro. Such a microrobotic approach has the potential to enable the development of active microcarriers with embedded functionalities for controlled and precisely localized therapeutic cell delivery. [ABSTRACT FROM AUTHOR]

A supramolecular hydrogel network is held intact through non‐covalent interactions among lowmolecular weight building blocks. The intermolecular interactions among the building blocks are important for stimuli‐responsive modulation and self‐healing properties. On page 2081 Aykutlu Dana, Mustafa O. Guler, and co‐workers show that a mussel‐inspired metal‐ion coordination into the supramolecular polymer network is advantageous for improving mechanical properties as well as retaining the original properties of the network. [ABSTRACT FROM AUTHOR]