This paper provides an overview of the trends in high-capacity IM-DD transmission in the O-band. We also present our recent research results of 400-Gb/s/lane transmission over installed 10-km 4-core fiber, achieving a 1.6-Tb/s total capacity. (c) 2024 The Author(s)

Long-haul transmission over 3520 km in a 4.725-THz WDM configuration with 225-GHzspacing in the C-band has been successfully demonstrated with a high-symbol-rate 200-GBd polarization-division-multiplexed QPSK signal, which was generated using in-house >110-GHz analogue multiplexers and >130-GHz-bandwidth electrical amplifiers based on ultra-broadband indium phosphide technologies.

This paper presents an over-110-GHz-bandwidth 2:1 analog multiplexer (AMUX) for ultra-broadband digital-to-analog (D/A) conversion subsystems. The AMUX was designed and fabricated by using newly developed \pmb0.25-μm -emitter-width InP double heterojunction bipolar transistors (DHBTs), which have a peak \pmbfT and \pmb f max of 460 and 480 GHz, respectively. The AMUX IC consists of lumped building blocks, including data-input linear buffers, a clock-input limiting buffer, an AMUX core, and an output linear buffer. The measured 3-dB bandwidth for data and clock paths are both over 110 GHz. In addition, it measures and obtains time-domain large-signal sampling operations of up to 180 GS/s. A 224-Gb/s (112-GBaud) four-level pulse-amplitude modulation (PAM4) signal was successfully generated by using this AMUX. To the best of our knowledge, this AMUX IC has the broadest bandwidth and the fastest sampling rate compared with any other previously reported AMUXes.

We recently found that heparin-binding domain 2 (Hep 2) of fibronectin (FN) exhibits cryptic anti-adhesive activity. In order to locate the anti-adhesive site, a number of synthetic peptides which represents the primary structure of the Hep 2 domain were characterized as to their ability to decrease the adhesion of A375SM melanoma cells to FN substrate. Only one peptide (T-E-A-T-I-T-G-L-E-P-G-T-E-Y-T-I-Y-V-I-A-L, residues 1835-1855) (peptide III14-2), which is situated between the previously identified adhesive sites, FN-C/H-I and II, decreased the cell adhesion to FN. Assaying of the anti-adhesive activities of sub-peptides showed that the hydrophobic moiety of peptide III14-2 (underlined sequence) seems to be indispensable for the anti-adhesive activity. These results suggest that anti-adhesive activity is closely associated with the sequence, Y-T-I-V-I-A-L, that is usually buried within the Hep 2 domain structure because of its hydrophobic nature.