Columbia University

Other

Harvard College

Ozgur Sahin

Xi Chen

Davis W Goodnight

Onur Cakmak

Duckhoe Kim

Aspects provide fluid responsive actuators and methods of using fluid responsive actuators capable of generating a power-to-volume ratio sufficient to inject a drug from a syringe within an injection period from about 1 to about 60 seconds after exposure of the fluid responsive elements to a fluid. The fluid responsive actuators can be used to inject viscous drugs to a patient.

Fluid responsive devices and methods

Water-responsive actuators and methods for creating water responsive actuators are disclosed. In some embodiments, the disclosed subject matter includes a first layer, for example a plastic tape, and a second layer, for example bacterial spores and cured adhesive. The second layer can be created in a pattern. The pattern can include joints, which can contract when exposed to dry air and can thereby bend the actuator, and can expand when exposed to humid air and thereby return the actuator its original position.

Systems and methods for fabricating water-responsive actuators

An AFM that suppress parasitic deflection signals is described. In particular, the AFM may use a cantilever with a probe tip that is offset along a lateral direction from a longitudinal axis of torsion of the cantilever. During AFM measurements, an actuator may vary a distance between the sample and the probe tip along a direction approximately perpendicular to a plane of the sample stage in an intermittent contact mode. Then, a measurement circuit may measure a lateral signal associated with a torsional mode of the cantilever during the AFM measurements. This lateral signal may correspond to a force between the sample and the probe tip. Moreover, a feedback circuit may maintain, relative to a threshold value: the force between the sample and the probe tip; and/or a deflection of the cantilever corresponding to the force. Next, the AFM may determine information about the sample based on the lateral signal.

AFM with suppressed parasitic signals

Evaporation-driven engines are disclosed herein. An example engine can include a water source having a high humidity zone proximate the surface of the water source, a supporting structure, and a hygroscopic material disposed on the supporting structure and configured to generate mechanical force in response to a changing relative humidity. The hygroscopic material can be repeatedly exposed to the high humidity zone and removed from the high humidity zone thereby causing the hygroscopic material to generate mechanical force.

Evaporation-driven engines

A method of determining the structure of a molecule can include labeling a first location on the molecule with a first DNA strand, and measuring a force-time waveform using the twisting of a T-shaped atomic force microscope cantilever scanning across the molecule. The cantilever can include a DNA probe having a first region that is complimentary to the first DNA strand.

Devices and methods for determining molecular structure

A method and system for providing an engine for producing mechanical energy through the absorption and evaporation of moisture uses a hygroscopic material in one or more configurations to do mechanical work. The hygroscopic material can include microbial spores, plant cells and cell materials, silk and hydrogel materials that absorb moisture and expand or swell when exposed to high relative humidity environments and shrink or return to nearly their original size or shape when exposed to low relative humidity environments wherein the moisture evaporates and is released. By exposing the hygroscopic material to a cycle of high relative humidity environments and low relative humidity environments, useful work can be done. One or more transmission elements can be used to couple the hygroscopic material to a generator that converts the mechanical energy to, for example, electrical energy. The hygroscopic material can be applied to flexible sheet materials that flex as the hygroscopic material absorbs or evaporates moisture. The hygroscopic material can also be applied to elastic conductive materials, such that the plates of a capacitor mechanically change the capacitance of the device.

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New York, NY, United States of America

Ozgur Sahin