Sökning: "modulator"

Visar resultat 6 - 10 av 223 avhandlingar innehållade ordet modulator.

1. 6. Galanin : a modulator of serotonin neurotransmission : relevance for depression

   Författare :Haleh Razani; Karolinska Institutet; Karolinska Institutet; []
   Nyckelord :galanin; 5-HT1A receptors; 5-HT; 8-OH-DPAT; fluoxetine; robalzotan; passive avoidance; microdialysis; mRNA; KD values; Bmax values; depression;

   Sammanfattning : Galanin is widely distributed throughout the central nervous system with multiple and diverse biological roles. In the rat, galanin-like immunoreactivity is expressed in a population of5-hydroxytryptamine (5-HT, serotonin) neurons in the dorsal raphe (DR) with extensive projections to the forebrain areas e.g., hippocampus. LÄS MER

3. 7. Neuronal Networks of Movement : Slc10a4 as a Modulator & Dmrt3 as a Gait-keeper

   Författare :Martin Larhammar; Klas Kullander; Leif Andersson; Åsa Wallén-Mackenzie; Robert Fyffe; Uppsala universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Synaptic vesicle transporter; Neuromodulation; Dopamine; Central Pattern Generator; Locomotion; Gait; Horse; Mouse; Commissural Inhibitory Interneuron; Neuroscience; Neurovetenskap;

   Sammanfattning : Nerve cells are organized into complex networks that comprise the building blocks of our nervous system. Neurons communicate by transmitting messenger molecules released from synaptic vesicles. Alterations in neuronal circuitry and synaptic signaling contribute to a wide range of neurological conditions, often with consequences for movement. LÄS MER

4. 8. Linear Interpolation D/A Converter Applied to Direct Digital RF Modulators

   Författare :Zhou Yijun; Institutionen för elektro- och informationsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Elektroteknik; Electrical engineering; SOC.; quadrature modulator; interpolation; filter; DSP; CMOS; DAC;

   Sammanfattning : This thesis deals with techniques for the full integration of radio frequency (RF) transmitter with CMOS technology. The theory and implementation of high performance digital-to-analog converters (DACs) for radio frequency (RF) transmitters have been studied. A linear interpolation DAC architecture is proposed. LÄS MER

5. 9. On High-Speed Digital-to-Analog Converters and Semi-Digital FIR Filters

   Författare :Mohammad Reza Sadeghifar; J Jacob Wikner; Robert Hägglund; Linköpings universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; DAC; RFDAC; SDFIR; FIR; semi-digital FIR filter; digital-to-analog converter; D A converter; data converter; mixed-signal integrated circuits; mixer DAC; IQ modulator; transmitter;

   Sammanfattning : High-speed and high-resolution digital-to-analog converters (DACs) are vital components in all telecommunication systems. Radio-frequency digital-to-analog converter (RFDAC) provides high-speed and high-resolution conversion from digital domain to an analog signal. RFDACs can be employed in direct-conversion radio transmitter architectures. LÄS MER

7. 10. Surface-normal multiple quantum well electroabsorption modulators : for optical signal processing and asymmetric free-space communication

   Författare :Stéphane Junique; Lars Thylén; Uzi Efron; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; spatial light modulators; quantum wells; optical resonator; Fabry–Pérot cavity; electroabsorption modulator; free–space optical communication; Photonics; Fotonik;

   Sammanfattning : Electroabsorption is the physical phenomenon by which the absorption of light in a medium can be controlled by applying an electric field. The Quantum–Confined Stark Effect, which makes the absorption band–edge in quantum wells very field–dependent, together with the strong absorption peak provided by excitons, are the physical foundations for the success of electroabsorption modulators based on quantum well structures in telecommunication networks. LÄS MER