The discovery of norepinephrine dates back to the late 1940s when the Swedish scientist, Ulf Svante von Euler first demonstrated that neurons of the sympathetic nervous system use norepinephrine, rather than epinephrine, as a neurotransmitter. Shortly thereafter in 1947, Peter Wilhelm Joseph Holtz demonstrated that norepinephrine occurred in the brain. Today, we know it is one of three major cate-cholamine (dopamine, norepinephrine, epinephrine) neurotransmitters found in the central nervous system (CNS). Over 50 years of subsequent research has led to an enormous accumulation of information regarding norepinephrine and its role in physiological and behavioral processes. In addition, drugs that directly manipulate brain norepinephrine have been used therapeutically for over 50 years, and even today, drugs are being developed that target noradrenergic neurons to deliver therapeutic effects. In fact, new disease indications continue to be identified for existing and newer noradrenergic drugs. Given the revered tenure of this relatively old neurotransmitter and the recent advances and subsequent theories about its contribution to health and disease in the CNS, the authors of this book decided the time was right to bring together historical and recent information about norepinephrine in one book. The intention of this volume is to provide the reader with a thorough understanding of the anatomy, physiology, molecular biology, pharmacology, and therapeutics of norepinephrine in the CNS, including an extensive review of the role of norepinephrine in diseases of the CNS.

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The objective of the proposed research is to extend the battery life in cellular handsets by improving the transmitter efficiency. Bandwidth efficient modulation formats, such as W-CDMA, encode much of the information in amplitude modulation. Therefore, linear transmitters must be used so as not to increase transmission errors, and cause interference in adjacent bands. Various engineering trade-offs were examined to find a suitable transmitter architecture for W-CDMA. Dynamic biasing of the transmitter power amplifier (PA) provides a simple way to improve efficiency for applications that require highly linear amplification. The envelope elimination and restoration (EER) PA or EER-based polar-modulated PA is an attractive solution since it has potential to achieve very high efficiency with high linearity. However, the major impediment to EER implementation has been the lack of power-efficient dynamic power supply circuits that can operate with sufficient modulation bandwidth, and simultaneously achieve the required modulation linearity. This work proposes several solutions to this problem. First, a dynamic supply circuit using delta modulation was designed and implemented. An open-loop EER PA with 48% peak efficiency was constructed and tested with a cellular band IS-95 CDMA signal with a bandwidth of 1.25 MHz. The low switching loss by using a delta modulator made the implementation of a wideband dynamic biasing circuit possible. Second, a dynamic supply circuit using dual-phase PWM was designed and implemented to achieve wider bandwidth, lower noise, and higher efficiency. An open-loop EER PA was implemented with the dynamic supply IC. A digital gain compensation scheme was developed to further increase bandwidth and linearity. This enables a dynamic supply circuit with lower switching frequency to have larger usable bandwidth with little increased power consumption. A cellular band W-CDMA voice signal was used to evaluate the performance of the overall PA. The PA achieved 50% efficiency while passing all required spectral specifications of W-CDMA standard. To increase the inherent low dynamic range of an EER PA, a dual-mode power amplifier combining an EER PA and power-level tracking PA was proposed. This work will contribute to the development of high efficiency, small-sized multi-mode linear PAs for battery-operated wireless handheld devices.

There are several advantages for optical communication in free space such as simplification,convenience, high bit rate,and sasy design,Free-space optical communication is an alternative for short distance communication. In this work, we desighn and fabricate the optical transmitter and receiver for delivery of audio signal in free-space communication. In circuit design section, audio signals proceed to analog to digital conversion (A/D)and then encode the data. The procedures of encoding block include parallel-series conversion, data cell process adding starter and stop bit, thereby modulate the laser by PCM format in free space. Data cell at receiver terminal will be decoded exactly and synchronized with transmitter terminal for data transmission. After digital to analog conversion, parallel-series data will decode to audio signals. We have accomplished the circuit design of optical transmitter and receiver for transmission of audio signals. Transmission bit rate, optical output power, and transmission distance at transmitter terminal are 200kbit/s,15mW,and >50m, respectively.

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International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California / Presentation for ITC 98 of Alcatel Espace last studies and developments regarding TTC Products This document lays on 3 parts: · a technical point of view · a technology/design description · a synthesis showing main performance and results

International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / An S-band telemetry transmitter has been developed for Expendable Launch Vehicles (ELV's) that can downlink data through NASA's Tracking and Data Relay Satellite System (TDRSS). The transmitter operates in the 2200 to 2300 MHz range and provides a number of unique features to achieve optimum performance in the launch vehicle environment: · Commandable QPSK or BPSK modulation format. · Data rates up to 10 Mbps. · Commandable concatenated coding provides superior link performance. · Premodulation filtering produces excellent spectral containment characteristics. · Phase noise of less than 3 degrees rms is maintained through launch and ascent vibration profiles. · A 30 watt nominal RF output power provides a robust RF link. · Two RF antenna output ports with commandable selection of all power out to either port or power split evenly between ports. · Operating modes and conditions of the unit can be monitored through a number of bilevel and analog outputs. · A ruggedized mechanical design provides a reliable communications link for launch vehicle environments.

ITC/USA 2009 Conference Proceedings / The Forty-Fifth Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2009 / Riviera Hotel & Convention Center, Las Vegas, Nevada / During the program researching on airborne telemetering transmitter of a certain remote telemetry system, small size and a variety of voltage on board are design difficulties. Due to the above important factors, the performance of power supply makes a big affect to the parameters of BPSK modulated signal, especially the EVM (Error Vector Magnitude). The author analyzes the cause of power supply noise and puts forward some suggestions to damp the noise. With these methods, the EVM of modulated signal is improved. Finally, we can conclude the related principles about the suppression of power supply noise.

ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / With recent developments in telemetry transmitter technologies, significantly greater DC to RF power efficiencies can be achieved. These new high efficiency transmitter designs may impact overall system design trade-offs by reducing the system size and weight requirements for batteries, heat sinks, and cabling. Furthermore, these fully DC isolated, next generation ARTM Tier 0, I and II enabled devices offer unique options to the platform designer in EMI/EMC control and system design. Advanced manufacturing techniques coupled with adaptive microprocessor control promises enhanced functionality, improved performance and reduced unit costs. The paper presents the performance of a new, high efficiency, telemetry transmitter topology and the possible system benefits involved with the application of this advanced transmitter technology within modern and legacy telemetry platforms. Specific sub-assembly circuit design techniques will be discussed and compared with prior design approaches.