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Microcatheters have enabled diverse minimally invasive endovascular operations and notable health benefits compared with open surgeries. However, with tortuous routes far from the arterial puncture site, the distal vascular regions remain challenging for safe catheter access. Therefore, we propose a wireless stent-shaped magnetic soft robot to be deployed, actively navigated, used for medical functions, and retrieved in the example M4 segment of the middle cerebral artery. We investigate shape-adaptively controlled locomotion in phantoms emulating the physiological conditions here, where the lumen diameter shrinks from 1.5 mm to 1 mm, the radius of curvature of the tortuous lumen gets as small as 3 mm, the lumen bifurcation angle goes up to 120°, and the pulsatile flow speed reaches up to 26 cm/s. The robot can also withstand the flow when the magnetic actuation is turned off. These locomotion capabilities are confirmed in porcine arteries ex vivo. Furthermore, variants of the robot could release the tissue plasminogen activator on-demand locally for thrombolysis and function as flow diverters, initiating promising therapies towards acute ischemic stroke, aneurysm, arteriovenous malformation, dural arteriovenous fistulas, and brain tumors. These functions should facilitate the robot’s usage in new distal endovascular operations., Nature Communications, 13 (1), ISSN:2041-1723

Manipulating and separating single label-free cells without biomarker conjugation have attracted significant interest in the field of single-cell research, but digital circuitry control and multiplexed individual storage of single label-free cells remain a challenge. Herein, by analogy with the electrical circuitry elements and electronical holes, we develop a pseudo-diamagnetophoresis (PsD) mattertronic approach in the presence of biocompatible ferrofluids for programmable manipulation and local storage of single PsD holes and label-free cells. The PsD holes conduct along linear negative micro-magnetic patterns. Further, eclipse diode patterns similar to the electrical diode can implement directional and selective switching of different PsD holes and label-free cells based on the diode geometry. Different eclipse heights and junction gaps influence the switching efficiency of PsD holes for mattertronic circuitry manipulation and separation. Moreover, single PsD holes are stored at each potential well as in an electrical storage capacitor, preventing multiple occupancies of PsD holes in the array of individual compartments due to magnetic Coulomb-like interaction. This approach may enable the development of large programmable arrays of label-free matters with high throughput, efficiency, and reliability as multiplex cell research platforms., Here, the authors present a pseudo-diamagnetophoresis mattertronic approach for programmable manipulation of label-free cells. Immersed in biocompatible ferrofluids, single cells are moved along linear negative micromagnetic patterns, switched at eclipse diode patterns and stored in potential wells.

Microrobots offer transformative solutions for non-invasive medical interventions due to their small size and untethered operation inside the human body. However, they must face the immune system as a natural protection mechanism against foreign threats. Here, non-immunogenic stealth zwitterionic microrobots that avoid recognition from immune cells are introduced. Fully zwitterionic photoresists are developed for two-photon polymerization 3D microprinting of hydrogel microrobots with ample functionalization: tunable mechanical properties, anti-biofouling and non-immunogenic properties, functionalization for magnetic actuation, encapsulation of biomolecules, and surface functionalization for drug delivery. Stealth microrobots avoid detection by macrophage cells of the innate immune system after exhaustive inspection (>90 hours), which has not been achieved in any microrobotic platform to date. These versatile zwitterionic materials eliminate a major roadblock in the development of biocompatible microrobots, and will serve as a toolbox of non-immunogenic materials for medical microrobot and other device technologies for bioengineering and biomedical applications., Advanced Materials, 32 (42), ISSN:0935-9648, ISSN:1521-4095

Tutoring programs that use children as tutors for other children are increasing in number and variety (Gartner, Kohler, & Riessman, 1971; Thelen, 1969). Although these programs are purported to be valuable in many ways for both tutors and tutees, the evidence supporting generalizations about tutoring has often been inconclusive. Typically, anecdotal reports rather than hard data have been gathered from tutorial programs in the schools (Bell, Garlock, & Colella, 1969; Costello & Martin, 1972; Goodman, 1971; Moskowitz, 1972; Office of Education, 1967; Swett, 1971). Some well-controlled research has been conducted, however.

Sixty-three elementary school-age children in an experimental teaching session provided either genuine or dissembled verbal praise to a student (confederate). Nonverbal behavior of the subjects was analyzed both by trained coders and by naive observers. As hypothesized, nonverbal cues disclosed when the participants were dissembling. Dissembling participants smiled less, showed less pleasant mouth expressions, paused more, and were judged to be less pleased with their students than nondissembling participants.