A Wirelessly Controlled Shape-Memory Alloy-Based Bistable Metal Swimming Device

Shape memory Nitinol has long been used for actuation. However, utilizing Nitinol to fabricate novel devices for various applications is a challenge, but has shown incredible promise and impacts. Bistable metal strips are widely adopted for shape morphing purposes (primarily in kid’s toys, e.g., snap bracelets) due to their easy and robust transformation between two states. In this paper, we combine Nitinol shape memory alloy and bistable metal strip to fabricate a swimming actuator with both slow moving and fast snapping capability, akin to an octopus swimming slowly in water, but quickly moving upon encountering a threat. The actuator developed here can also swim in multiple directions, all controlled by a wireless module. Furthermore, we demonstrate that an on-board sensor can be incorporated for potential environmental monitoring applications. Taken together, along with the fact that the device developed here has no mechanical parts, makes this an interesting potential alternative to more expensive, and energy consuming boats.

PR38 Progress Towards Integrated Photon-Pair Sources and Their Applications (1640968-Y5)

The objective of this project was to make significant advances in quantum optical communications through the design, fabrication and demonstration of novel devices at the microchip scale. The principal goal of the device sub-project was to develop key building blocks for photonic microchips that are energy-efficient, leverages modern micro-fabrication platforms, reduces operational complexity and improve scalability with the potential for future adoption by industry. Summary of a Project Outcomes report of research funded by the U.S. National Science Foundation under Project Number 1640968 (Year 5).

Novel approaches in 3D live cell microscopy

Microscopy methods for 3D live cell imaging, including various techniques, challenges and restrictions, are described. Novel devices for application of these methods in combination with 3D printed optics are presented and discussed.

Endoscopic Submucosal Resection (ESR) - a technique using novel devices for incision and resection of neoplastic lesions

Background and study aims: Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are established techniques for the treatment of superficial gastrointestinal neoplasia. Limitations of EMR are the low en bloc resection rates for larger lesions resulting in frequent recurrences. Major disadvantages of ESD are technical difficulty and long procedure times. Here, we evaluated technical feasibility and safety of newly designed devices to perform en bloc resection of lesions sized between ca. 20-40 mm. The method will be referred to as Endoscopic Submucosal Resection (ESR). Patients and methods: This case series included 93 lesions from different localizations (11x stomach, 25x colon, 57x rectum) with a median size of 29 (10-70) mm. ESR was carried out with two novel instruments for circumferential mucosal incision and for deep submucosal resection. Results: Resection by ESR was feasible in all cases. En bloc and R0 rates were insufficient when ESR was attempted without prior circumferential mucosal incision. However, en bloc and R0 resection rates were 70% and 63%, respectively when mucosal incision was done before application of the device for submucosal resection. We observed 3 complications (2 delayed bleedings, one microperforation) but no case of emergency surgery and no 30-day mortality. Conclusions: The series demonstrates feasibility and excellent safety of ESR using two novel devices for en bloc resection of early gastrointestinal neoplasia. The technique holds the promise of relative technical ease combined with high efficacy.

A Novel and Inexpensive Technique for High-tension Tendon Clamping with Expandable Mesh Sleeving for in Vitro Foot Biomechanics Testing

In vitro biomechanical testing is common in the field of orthopedics when novel devices are investigated prior to human trials. It is typically necessary to apply loads through tendons to simulate normal activities, such as walking during a foot and ankle study. However, attachment of tendons to linear actuators has proven challenging because of the tendency of clamps to either slip off or rupture the tendon. Freeze clamping is generally accepted as the gold standard for very high load testing in excess of 3000 N, but is expensive, time-consuming, and requires significant ancillary equipment. Purely mechanical solutions such as metal jaw clamps, wire meshes, and others have been explored, but these techniques are either costly, have low load capacities, or have not proven to be reproducible. We have developed a novel tendon clamping technique that utilizes a slip-resistant polyester mesh sleeving that encases the tendon and is fixated at the bottom of the tendon/sleeve interaction with a giftbox suture. The loose end of the sleeving can then be tied in to the linear actuator or load cell apparatus using a timber hitch knot. The sleeving technique allows for loads of 2000-2500 N on the Achilles tendon, and is inexpensive, reproducible, and can be modified to apply loads to smaller tendons as well, though a length of tendon/sleeve overlap of at least 16 cm is required to reach maximum loads. This technique should assist researchers in integrating muscle forces into future biomechanical study designs.

Readout of an antiferromagnetic spintronics system by strong exchange coupling of Mn2Au and Permalloy

In antiferromagnetic spintronics, the read-out of the staggered magnetization or Néel vector is the key obstacle to harnessing the ultra-fast dynamics and stability of antiferromagnets for novel devices. Here, we demonstrate strong exchange coupling of Mn2Au, a unique metallic antiferromagnet that exhibits Néel spin-orbit torques, with thin ferromagnetic Permalloy layers. This allows us to benefit from the well-established read-out methods of ferromagnets, while the essential advantages of antiferromagnetic spintronics are only slightly diminished. We show one-to-one imprinting of the antiferromagnetic on the ferromagnetic domain pattern. Conversely, alignment of the Permalloy magnetization reorients the Mn2Au Néel vector, an effect, which can be restricted to large magnetic fields by tuning the ferromagnetic layer thickness. To understand the origin of the strong coupling, we carry out high resolution electron microscopy imaging and we find that our growth yields an interface with a well-defined morphology that leads to the strong exchange coupling.

Strain-controlled thermoelectric properties of phosphorene-carbon monosulfide hetero-bilayers

The application of strain to 2D materials allows manipulating the electronic, magnetic, and thermoelectric properties. These physical properties are sensitive to slight variations induced by tensile and compressive strain and the uniaxial strain direction. Herein, we take advantage of the reversible semiconductor-metal transition observed in certain monolayers to propose a hetero-bilayer device. We propose to pill up phosphorene (layered black phosphorus) and carbon monosulfide monolayers. In the first, such transition appears for positive strain, while the second appears for negative strain. Our first-principle calculations show that depending on the direction of the applied uniaxial strain; it is possible to achieve reversible control in the layer that behaves as an electronic conductor while the other layer remains as a thermal conductor. The described strain-controlled selectivity could be used in the design of novel devices.