11 research outputs found
Brain-controlled cycling system for rehabilitation following paraplegia with delay-time prediction
Objective: Robotic rehabilitation systems have been investigated to assist with motor dysfunction recovery in patients with lower-extremity paralysis caused by central nervous system lesions. These systems are intended to provide appropriate sensory feedback associated with locomotion. Appropriate feedback is thought to cause synchronous neuron firing, resulting in the recovery of function. Approach: In this study, we designed and evaluated an ergometric cycling wheelchair, with a brain-machine interface (BMI), that can force the legs to move by including normal stepping speeds and quick responses. Experiments were conducted in five healthy subjects and one patient with spinal cord injury (SCI), who experienced the complete paralysis of the lower limbs. Event-related desynchronization (ERD) in the β band (18‐28 Hz) was used to detect lower-limb motor images. Main results: An ergometer-based BMI system was able to safely and easily force patients to perform leg movements, at a rate of approximately 1.6 seconds/step (19 rpm), with an online accuracy rate of 73.1% for the SCI participant. Mean detection time from the cue to pedaling onset was 0.83±0.31 s Significance: This system can easily and safely maintain a normal walking speed during the experiment and be designed to accommodate the expected delay between the intentional onset and physical movement, to achieve rehabilitation effects for each participant. Similar BMI systems, implemented with rehabilitation systems, may be applicable to a wide range of patients
Spatiotemporal Control of Electrokinetic Transport in Nanofluidics Using an Inverted Electron-Beam Lithography System
Manipulation
techniques
of biomolecules have been proposed for biochemical analysis which
combine electrokinetic dynamics, such as electrophoresis or electroosmotic
flow, with optical manipulation to provide high throughput and high
spatial degrees of freedom. However, there are still challenging problems
in nanoscale manipulation due to the diffraction limit of optics.
We propose here a new manipulation technique for spatiotemporal control
of chemical transport in nanofluids using an inverted electron-beam
(EB) lithography system for liquid samples. By irradiating a 2.5 keV
EB to a liquid sample through a 100-nm-thick SiN membrane, negative
charges can be generated within the SiN membrane, and these negative
charges can induce a highly focused electric field in the liquid sample.
We showed that the EB-induced negative charges could induce fluid
flow, which was strong enough to manipulate 240 nm nanoparticles in
water, and we verified that the main dynamics of this EB-induced fluid
flow was electroosmosis caused by changing the zeta potential of the
SiN membrane surface. Moreover, we demonstrated manipulation of a
single nanoparticle and concentration patterning of nanoparticles
by scanning EB. Considering the shortness of the EB wavelength and
Debye length in buffer solutions, we expect that our manipulation
technique will be applied to nanomanipulation of biomolecules in biochemical
analysis and control
Spatiotemporal Control of Electrokinetic Transport in Nanofluidics Using an Inverted Electron-Beam Lithography System
Manipulation
techniques
of biomolecules have been proposed for biochemical analysis which
combine electrokinetic dynamics, such as electrophoresis or electroosmotic
flow, with optical manipulation to provide high throughput and high
spatial degrees of freedom. However, there are still challenging problems
in nanoscale manipulation due to the diffraction limit of optics.
We propose here a new manipulation technique for spatiotemporal control
of chemical transport in nanofluids using an inverted electron-beam
(EB) lithography system for liquid samples. By irradiating a 2.5 keV
EB to a liquid sample through a 100-nm-thick SiN membrane, negative
charges can be generated within the SiN membrane, and these negative
charges can induce a highly focused electric field in the liquid sample.
We showed that the EB-induced negative charges could induce fluid
flow, which was strong enough to manipulate 240 nm nanoparticles in
water, and we verified that the main dynamics of this EB-induced fluid
flow was electroosmosis caused by changing the zeta potential of the
SiN membrane surface. Moreover, we demonstrated manipulation of a
single nanoparticle and concentration patterning of nanoparticles
by scanning EB. Considering the shortness of the EB wavelength and
Debye length in buffer solutions, we expect that our manipulation
technique will be applied to nanomanipulation of biomolecules in biochemical
analysis and control