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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

An inductively powered multichannel wireless implantable neural recording system (WINeR)

Lee, Seung Bae 21 September 2015 (has links)
A multi-channel wireless implantable neural recording (WINeR) system for electrophysiology and behavioral neuroscience research applications was proposed. The system is composed of two units: a system-on-a-chip (SoC) transmitter (Tx) unit and a receiver (Rx) unit. In the Tx unit, the outputs are combined with marker signals and modulated into pulse widths after the neural signals are amplified and filtered by an array of low-noise amplifiers (LNA). The next step involves time-division multiplexing (TDM) of pulse-width modulation (PWM) signals. The TDM-PWM signal drives RF transmitter block and is transmitted by an antenna. To satisfy the needs of neuroscientists during animal experiments, the proposed WINeR system provides long-term recording with inductive powering and stimulus-artifact rejection for closed-loop operations, which requires simultaneous stimulation and recording. The Rx is another critical unit for wireless-link communication. To increase the area of wireless coverage, multiple antennas are used for the Rx. In addition, the automatic frequency-tracking method is used to track free-running Tx frequencies, and a smart time-to-digital conversion method is used to reduce noise and interference. A high-throughput computer interface and software are also developed to continuously receive and store neural data. The WINeR system is a potential tool for neuroscientists due to several advantages, such as a reliable wireless link with large coverage and no blind spots, low power consumption, an unlimited power source, and a stimulation function.
2

Photovoltaic (PV) and fully-integrated implantable CMOS ICs

Ayazianmavi, Sahar 12 July 2012 (has links)
Today, there is an ever-growing demand for compact, and energy autonomous, implantable biomedical sensors. These devices, which continuously collect in vivo physiological data, are imperative in the next generation patient monitoring systems. One of the fundamental challenges in their implementation, besides the obvious size constraints and the tissue-to-electronics biocompatibility impediments, is the efficient means to wirelessly deliver power to them. This work addresses this challenge by demonstrating an energy-autonomous and fully-integrated implantable sensor chip which takes advantage of the existing on-chip photodiodes of a standard CMOS process as photovoltaic (PV) energy-harvesting cells. This 2.5 mm × 2.5 mm chip is capable of harvesting [mu]W’s of power from the ambient light passing through the tissue and performing real-time sensing. This system is also MRI compatible as it includes no magnetic material and requires no RF coil or antennae. In this dissertation, the optical properties of tissue and the capabilities of the CMOS integrated PV cells are studied first. Next, the implementation of an implantable sensor using such PV devices is discussed. The sensor characterizing and the in vitro measurement results using this system, demonstrate the feasibility of monolithically integrated CMOS PV-driven implantable sensors. In addition, they offer an alternative method to create low-cost and mass-deployable energy autonomous ICs in biomedical applications and beyond. / text
3

STT Event Stream Feature to Assist Software Testing of Impantable Devices in St. Jude Medical

Park, Yong J 01 March 2009 (has links) (PDF)
During development and testing of the pacemaker and defibrillator device functionality, engineers in the cardiac rhythm management industry use a patient simulator to ensure device functionality properly before device is tested with an animal or a human. The patient simulator is also used in the formal device product testing. In St. Jude Medical, a patient simulator called Simulation Test Tool (STT) has been developed and used by engineers in the company. While the Heart Simulator (HS) feature based on physiological heart model in the STT has been served as a main cardiac rhythm simulation feature, there has been an increasing need of a new feature in the STT for engineers to create heart rhythm scenarios more easily and effectively. This thesis covers the design and implementation of the new STT feature, called Event Stream, which allows users to create heart rhythm scenarios using simple text string based syntax for testing device functionality.
4

Metronomic photodynamic therapy using an implantable LED device and orally administered 5-aminolevulinic acid / 留置型LEDデバイスと経口5-アミノレブリン酸を用いたメトロノミック光線力学療法

Kirino, Izumi 24 July 2023 (has links)
京都大学 / 新制・論文博士 / 博士(医学) / 乙第13565号 / 論医博第2292号 / 新制||医||1068(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 小林, 恭, 教授 小濱, 和貴, 教授 上杉, 志成 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM
5

Design of a Closed Loop System for Glaucoma Treatment including Measurement of Intraocular Pressure and Therapeutic Stimulation of the Eye

Rachael Swenson (6615704) 11 June 2019 (has links)
<p>Glaucoma is the leading cause of irreversible blindness worldwide effecting more than 2.7 million people in the U.S alone. Treatments exist in the form of both pharmaceutical and surgical options, but often do not provide the desired efficacy. For example, the failure rate of a trabeculectomy procedure is 39% within 5 years. Additionally, none of the current glaucoma treatments allow for closed loop monitoring of pressure, therefore requiring more frequent doctor visits. Glaucoma management can be improved through the use of a closed loop application of electroceutical treatment. The goal is to develop an implantable device that will be inserted into the eye to monitor intraocular pressure (IOP) and provide responsive therapeutic stimulation to the eye. I designed a discrete pressure monitoring system that interacts with a bare die piezoresistive pressure sensor. The system is based on a Wheatstone bridge design which translates the input resistances of the pressure sensor into a voltage output. This system has an average accuracy of 0.53 mmHg and draws 295 µW of power. I then combined this pressure system with data processing code and Howland current pump stimulation circuitry. This simulation system can output up to 1.05 mA of current for electroceutical intraocular stimulation to lower IOP. Future work will involve miniaturizing the circuitries in the form of an ASIC and packaging the entire system into an ocular implant. This implant can wirelessly monitor IOP and provide therapeutic stimulation to lower IOP. A reliable, closed loop method of lowering IOP would greatly benefit the ever-growing population affected by glaucoma.</p>
6

RF Energy Harvesting for Implantable ICs with On-chip Antenna

Liu, Yu-Chun 01 January 2014 (has links)
Nowadays, as aging population increasing yearly, the health care technologies for elder people who commonly have high blood pressure or Glaucoma issues have attracted much attention. In order to care of those people, implantable integrated circuits (ICs) in human body are the direct solution to have 24/7 days monitoring with real-time data for diagnosis by patients themselves or doctors. However, due to the small size requirement for the implanted ICs located in human organs, it's quite challenging to integrate with transmitting and receiving antenna in a single chip, especially operating in 5.8-GHz ISM band. This research proposes a new idea to solve the issue of integrating an on-chip antenna with implanted ICs. By adding an additional dielectric substrate upon the layer of silicon oxide in CMOS technology, utilizing the metal-6, it can form an extremely compact 3D-structure on-chip antenna which is able to be placed in human eye, heart or even in a few mm-diameter vessels. The proposed 3D on-chip antenna is only 1x1x2.8 mm3 with -10 dB gain and 10% efficiency, which has capability to communicate at least within 5 cm distance. The entire implanted battery-less wireless system has also been developed in this research. A designed 30% efficiency Native NMOS rectifier could generate 1 V and 1 mA to supply the designed low power transmitter including voltage-controlled oscillator (VCO) and power amplifier (PA). The entire system performance is well evaluated by link budget analysis and the simulation result demonstrates the possibility and feasibility of future on-demand easy-to-design implantable SoC.
7

A Miniature Wireless Neural Recording and Stimulating System for Chronic Implantation in Freely Moving Animals

Kanchwala, Mustafa Ashiq Hussain January 2018 (has links)
No description available.
8

WIRELESS BATTERYLESS IN VIVO BLOOD PRESSURE SENSING MICROSYSTEM FOR SMALL LABORATORY ANIMAL REAL-TIME MONITORING

Cong, Peng 04 December 2008 (has links)
No description available.
9

Přístroje EMD a jejich ovlivnění / EMD instruments and electromagnetic mmunity

Mikula, Dalibor January 2009 (has links)
The work deals with implantable devices and possibilities of interference of elektromagnetic field. At first, the electromagnetic compatibility is discussed. Basic terms are explained, followed by insisting on resources of possible distrurbing of implantable devices and standards dealing with this issue. Furthermore, short chapter about devices affecting function of implantable devices is introduced. It means devices which patients with implantable devices may meet in common life, as well as devices used in common life, also devices used jn medical environment. In the next part, measuring process of electromamagnetic effect in working compartment of FN Brno magnetotheraphy and elektrotheraphy is devised. There is a concept of measuring card thanks to which impulses of implantable devices are measured. Finally, a description of measuring on implantable devices in FN Brno. MIKULA, D. EMD instruments and electromagnetic immunity. Brno, 2009. 74 s. Master’s thesis in Brno University of technology on faculty of elektrical engeenerig and communication. Supervisor Ing. Marie Havlíková , Ph.D.

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