Augmented Transcutaneous Stimulation Using an Injectable Electrode: A Computational Study

Minimally invasive neuromodulation technologies seek to marry the neural selectivity of implantable devices with the low-cost and non-invasive nature of transcutaneous electrical stimulation (TES). The Injectrode® is a needle-delivered electrode that is injected onto neural structures under image guidance. Power is then transcutaneously delivered to the Injectrode using surface electrodes. The Injectrode serves as a low-impedance conduit to guide current to the deep on-target nerve, reducing activation thresholds by an order of magnitude compared to using only surface stimulation electrodes. To minimize off-target recruitment of cutaneous fibers, the energy transfer efficiency from the surface electrodes to the Injectrode must be optimized. TES energy is transferred to the Injectrode through both capacitive and resistive mechanisms. Electrostatic finite element models generally used in TES research consider only the resistive means of energy transfer by defining tissue conductivities. Here, we present an electroquasistatic model, taking into consideration both the conductivity and permittivity of tissue, to understand transcutaneous power delivery to the Injectrode. The model was validated with measurements taken from (n = 4) swine cadavers. We used the validated model to investigate system and anatomic parameters that influence the coupling efficiency of the Injectrode energy delivery system. Our work suggests the relevance of electroquasistatic models to account for capacitive charge transfer mechanisms when studying TES, particularly when high-frequency voltage components are present, such as those used for voltage-controlled pulses and sinusoidal nerve blocks.

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Augmented Transcutaneous Stimulation Using an Injectable Electrode

10.1101/2021.09.29.462482 ◽

2021 ◽

Author(s):

Nishant Verma ◽

Robert D Graham ◽

Jonah Mudge ◽

James K Trevathan ◽

Manfred Franke ◽

...

Keyword(s):

Energy Transfer ◽

Low Cost ◽

Coupling Efficiency ◽

Power Delivery ◽

Nerve Blocks ◽

Surface Electrodes ◽

Non Invasive ◽

Transcutaneous Stimulation ◽

Order Of Magnitude ◽

Neural Selectivity

AbstractMinimally invasive neuromodulation technologies seek to marry the neural selectivity of implantable devices with the low-cost and non-invasive nature of transcutaneous electrical stimulation (TES). The Injectrode® is a needle-delivered electrode that is injected onto neural structures under image guidance. Power is then transcutaneously delivered to the Injectrode using surface electrodes. The Injectrode serves as a low-impedance conduit to guide current to the deep on-target nerve, reducing activation thresholds by an order of magnitude compared to using only surface stimulation electrodes. To minimize off-target recruitment of cutaneous fibers, the energy transfer efficiency from the surface electrodes to the Injectrode must be optimized. TES energy is transferred to the Injectrode through both capacitive and resistive mechanisms. Electrostatic finite element models generally used in TES research consider only the resistive means of energy transfer by defining tissue conductivities. Here, we present an electroquasistatic model, taking into consideration both the conductivity and permittivity of tissue, to understand transcutaneous power delivery to the Injectrode. The model was validated with measurements taken from (n=4) swine cadavers. We used the validated model to investigate system and anatomic parameters that influence the coupling efficiency of the Injectrode energy delivery system. Our work suggests the relevance of electroquasistatic models to account for capacitive charge transfer mechanisms when studying TES, particularly when high-frequency voltage components are present, such as those used for voltage-controlled pulses and sinusoidal nerve blocks.

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CrossGR

Proceedings of the ACM on Interactive Mobile Wearable and Ubiquitous Technologies ◽

10.1145/3448100 ◽

2021 ◽

Vol 5 (1) ◽

pp. 1-23

Author(s):

Xinyi Li ◽

Liqiong Chang ◽

Fangfang Song ◽

Ju Wang ◽

Xiaojiang Chen ◽

...

Keyword(s):

Gesture Recognition ◽

Low Cost ◽

User Involvement ◽

Recognition System ◽

Training Data ◽

Generative Adversarial Network ◽

Adversarial Network ◽

Target User ◽

Order Of Magnitude ◽

Training Examples

This paper focuses on a fundamental question in Wi-Fi-based gesture recognition: "Can we use the knowledge learned from some users to perform gesture recognition for others?". This problem is also known as cross-target recognition. It arises in many practical deployments of Wi-Fi-based gesture recognition where it is prohibitively expensive to collect training data from every single user. We present CrossGR, a low-cost cross-target gesture recognition system. As a departure from existing approaches, CrossGR does not require prior knowledge (such as who is currently performing a gesture) of the target user. Instead, CrossGR employs a deep neural network to extract user-agnostic but gesture-related Wi-Fi signal characteristics to perform gesture recognition. To provide sufficient training data to build an effective deep learning model, CrossGR employs a generative adversarial network to automatically generate many synthetic training data from a small set of real-world examples collected from a small number of users. Such a strategy allows CrossGR to minimize the user involvement and the associated cost in collecting training examples for building an accurate gesture recognition system. We evaluate CrossGR by applying it to perform gesture recognition across 10 users and 15 gestures. Experimental results show that CrossGR achieves an accuracy of over 82.6% (up to 99.75%). We demonstrate that CrossGR delivers comparable recognition accuracy, but uses an order of magnitude less training samples collected from the end-users when compared to state-of-the-art recognition systems.

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Investigation of serial coherent laser beam combination based on Brillouin amplification

Laser and Particle Beams ◽

10.1017/s0263034607070127 ◽

2007 ◽

Vol 25 (1) ◽

pp. 79-83 ◽

Cited By ~ 22

Author(s):

SHUANGYI WANG ◽

ZHIWEI LÜ ◽

DIANYANG LIN ◽

LEI DING ◽

DONGBIN JIANG

Keyword(s):

Laser Beam ◽

High Power ◽

Simple Structure ◽

Low Cost ◽

Coupling Efficiency ◽

Laser Beams ◽

Beam Combination ◽

Multiple Beams ◽

Combination Scheme ◽

Stokes Beam

Based on transferring energy from multiple pump beams into one Stokes beam using Brillouin amplification, a serial coherent laser beam combination scheme is presented, which has many advantages, such as, simple structure, low cost, ease of adjustment, higher load capability, scalable easily, etc. Furthermore, it has been demonstrated that the combination of several beams using this method is theoretically possible. But in practice, the amplification of high power Stokes beam is a key problem to solve. In this paper, the amplification of Stokes beam whose power is higher than the pump beam is first studied and proved experimentally. Coupling the two laser beams by this method is proved experimentally, and the coupling efficiency reaches more than 80%. Then the feasibility of multiple beams combination based on Brillouin amplification is analyzed and tested theoretically.

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Comparison of electrohysterogram signal measured by surface electrodes with different designs: A computational study with dipole band and abdomen models

Scientific Reports ◽

10.1038/s41598-017-17109-3 ◽

2017 ◽

Vol 7 (1) ◽

Cited By ~ 1

Author(s):

Pei Gao ◽

Dongmei Hao ◽

Yang An ◽

Ying Wang ◽

Qian Qiu ◽

...

Keyword(s):

Computational Study ◽

Surface Electrodes ◽

Dipole Band

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Automated text messaging follow-up for patients who receive peripheral nerve blocks

Regional Anesthesia and Pain Medicine ◽

10.1136/rapm-2021-102472 ◽

2021 ◽

pp. rapm-2021-102472

Author(s):

Daniel Gessner ◽

Oluwatobi O Hunter ◽

Alex Kou ◽

Edward R Mariano

Keyword(s):

Regional Anesthesia ◽

Nerve Block ◽

Text Messaging ◽

Low Cost ◽

Automated System ◽

Phone Call ◽

Nerve Blocks ◽

Patient Response ◽

Patient Reported

BackgroundRoutine follow-up of patients who receive a nerve block for ambulatory surgery typically consists of a phone call from a regional anesthesia clinician. This process can be burdensome for both patients and clinicians but is necessary to assess the efficacy and complication rate of nerve blocks.MethodsWe present our experience developing an automated system for completing follow-up via short message service text messaging and our preliminary results using it at three clinical sites. The system is built on REDCap, a secure online research data capture platform developed by Vanderbilt University and currently available worldwide.ResultsOur automated system queried patients who received a variety of nerve block techniques, assessed patient-reported nerve block duration, and surveyed patients for potential complications. Patient response rate to text messaging averaged 91% (higher than our rates of daily phone contact reported previously) for patients aged 18 to 90 years.ConclusionsGiven the wide availability of REDCap, we believe this automated text messaging system can be implemented in a variety of health systems at low cost with minimal technical expertise and will improve both the consistency of patient follow-up and the service efficiency of regional anesthesia practices.

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231 A Low-Cost, Reusable Model for Teaching Paraspinous Cervical Nerve Blocks to Residents

Annals of Emergency Medicine ◽

10.1016/j.annemergmed.2018.08.236 ◽

2018 ◽

Vol 72 (4) ◽

pp. S91-S92

Author(s):

E.A. Nguyen ◽

D. Fujihara ◽

R. DeNolf ◽

M. Johnson ◽

V. Totten ◽

...

Keyword(s):

Low Cost ◽

Cervical Nerve ◽

Nerve Blocks

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Silicon Photonic Micro-Transceivers for Beyond 5G Environments

Applied Sciences ◽

10.3390/app112210955 ◽

2021 ◽

Vol 11 (22) ◽

pp. 10955

Author(s):

Kazuhiko Kurata ◽

Luca Giorgi ◽

Fabio Cavaliere ◽

Liam O’Faolain ◽

Sebastian A. Schulz ◽

...

Keyword(s):

Quantum Dot ◽

High Temperatures ◽

Low Cost ◽

Laser System ◽

Data Rate ◽

Ambient Temperatures ◽

Quantum Dot Laser ◽

Silicon Photonic ◽

Order Of Magnitude ◽

And Performance

Here, we report on the design and performance of a silicon photonic micro-transceiver required to operate in 5G and 6G environments at high ambient temperatures above 105 °C. The four-channel “IOCore” micro-transceiver incorporates a 1310 nm quantum dot laser system and operates at a data rate of 25 Gbps and higher. The 5 × 5 mm micro-transceiver chip benefits from a multimode coupling interface for low-cost assembly and robust connectivity at high temperatures as well as an optical redundancy scheme, which increases reliability by over an order of magnitude.

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Über die Abhängigkeit der relativen biologischen Wirksamkeit hochenergetischer Bremsstrahlen von der durchstrahlten Materieschicht / Dependence of the Relative Biological Efficiency of High Energy Bremssstrahlen on the Depth in a Phantom

Zeitschrift für Naturforschung B ◽

10.1515/znb-1969-1227 ◽

1969 ◽

Vol 24 (12) ◽

pp. 1633-1640 ◽

Cited By ~ 1

Author(s):

F. Stähler ◽

F. Zywietz ◽

W. Ewert ◽

H. A. Künkel

Keyword(s):

Energy Transfer ◽

Vicia Faba ◽

Linear Energy Transfer ◽

Experimental Error ◽

Nuclear Reactions ◽

High Energy ◽

Biological Efficiency ◽

Heavy Particles ◽

Order Of Magnitude

The Relative Biological Efficiency (RBE) of 6-GeV-bremsstrahlung on 3-days-old seedlings of Vicia faba was investigated with the Deutsches ElektronenSynchrotron. Dosimetry was carried out by means of the butanol-sensitized FeII/FeIII-reaction. In a Lucite-phantom we observed an increase of the RBE from 0,65 at the surface to values of about 2 at a depth of 40 cm. As changes of that order of magnitude are doubtless beyond the limits of the maximum experimental error we suppose that production of heavy particles by nuclear reactions such as (γ, n) or (γ, p) in deeper layers of matter might cause an increase of the linear energy transfer of the beam.

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