Simultaneous waveform and bit-error-rate measurements of 66 GBd PDM-16-QAM signals

We demonstrate waveform analysis and BER measurements of a PDM-NRZ-16-QAM signal at a record base symbol rate using asynchronous optical under-sampling. A BER below the FEC limit was achieved at 528 Gbit/s

Time-resolved error vector magnitude for transmitter mask testing in coherent optical transmission systems

We propose a novel transition-sensitive measurement approach for coherent optical systems. The time-resolved error vector magnitude (EVM), combined with mask testing, is a powerful tool for pass/fail testing of transmitters in coherent systems

Optical phase-sensitive sampling for high fidelity capture of advanced, high baud-rate optical waveforms and signals

We discuss all-optical sampling techniques to capture optical waveforms with both high fidelity and time resolution. Different approaches are possible, each with associated performance - complexity trade-offs. We cover not only sampling of intensity waveforms but also complex modulation formats such as QPSK and 16-QAM and also discuss the distinctions between real time sampling and equivalent-time sampling

Optical phase-sensitive sampling for high fidelity capture of advanced, high baud-rate optical waveforms and signals

We discuss all-optical sampling techniques to capture optical waveforms with both high fidelity and time resolution. Different approaches are possible, each with associated performance - complexity trade-offs. We cover not only sampling of intensity waveforms but also complex modulation formats such as QPSK and 16-QAM and also discuss the distinctions between real time sampling and equivalent-time sampling

Differential gene expression changes for complement C1q and C3 after injuries to dorsal and ventral nerve roots

C1q is an initiating protein in the classical complement cascade and is a key element in the inflammatory response to injuries in the nervous system. Interestingly, it has been shown to be expressed by immature neurons and is localized to synapses. Mice that are deficient to C1q or the downstream complement factor C3 show severe defects in elimination of synapses during development (Stevens et al., 2007). This can lead to nonappropriate connections, increased excitatory connectivity and epileptiform activity. Recent in vitro studies indicate that C1q can directly promote neuronal survival (Benoit and Tenner, 2011). In this study we have examined expression changes after injuries to dorsal and ventral roots in 18 adult rats using Affymetrix Rat Gene ST 1.0 arrays.The data suggest that the cute response in genes for complement factors C1q and C3 is different after different nerve root lesions. The ventral root replantation and nerve injuries are followed by a regenerative response while dorsal root transection and ventral root avulsion are examples of non-regenerative conditions