One-way Quantum Key Distribution System based on Planar Lightwave Circuits

We developed a one-way quantum key distribution (QKD) system based upon a planar lightwave circuit (PLC) interferometer. This interferometer is expected to be free from the backscattering inherent in commercially available two-way QKD systems and phase drift without active compensation. A key distribution experiment with spools of standard telecom fiber showed that the bit error rate was as low as 6% for a 100-km key distribution using an attenuated laser pulse with a mean photon number of 0.1 and was determined solely by the detector noise. This clearly demonstrates the advantages of our PLC-based one-way QKD system over two-way QKD systems for long distance key distribution.Comment: 23 pages, 5 figure

BB84 Quantum Key Distribution System based on Silica-Based Planar Lightwave Circuits

We constructed an optical interferometer for a Bennett-Brassard quantum key distribution system using integrated optics based on planar lightwave circuit technology, and tested its operation and stability. Experimental results show that this interferometer is useful in implementing a practical quantum key distribution system.Comment: 11 pages, 2 figure

Single-photon interference over 150-km transmission using silica-based integrated-optic interferometers for quantum cryptography

We have demonstrated single-photon interference over 150 km using time-division interferometers for quantum cryptography, which were composed of two integrated-optic asymmetric Mach-Zehnder interferometers, and balanced gated-mode photon detectors. The observed fringe visibility was more than 80% after 150-km transmission.Comment: 10 pages, 2 figures, submitted to Electronics Letter

A Landmark Point Analysis with Cytotoxic Agents for Advanced NSCLC

IntroductionAs a result of recent publications, we hypothesized that period of 8 weeks after initiation of treatment is a useful landmark point for cytotoxic agents for advanced non-small cell lung cancer (NSCLC). To test this hypothesis, we conducted landmark analyses with clinical trials employing cytotoxic agents. Our goal was to assess the proper design of clinical trials with cytotoxic agents for NSCLC for maximizing patients’ benefit.MethodsWe conducted landmark analyses of a phase II study of pemetrexed in locally advanced or metastatic NSCLC and a phase III study of Four-Arm Cooperative Study for advanced NSCLC. A total of 806 patients who received chemotherapy (pemetrexed, cisplatin and irinotecan, paclitaxel and carboplatin, cisplatin and gemcitabine, cisplatin and vinorelbine) were included in this assessment.ResultsTumor-shrinkage rate at 8 weeks was significantly associated with longer survival in the study with pemetrexed (p = 0.043), whereas tumor-shrinkage rate at 4 weeks did not correlated with survival (p = 0.139). Similarly, using the Four-Arm Cooperative Study data, the optimal landmark point was 8 weeks (p = 0.002), not 4 weeks (p = 0.190).ConclusionThe landmark point for NSCLC was 8 weeks with all cytotoxic agents in our analysis when the therapy was given as a frontline or subsequent therapy. Our result suggests the concept of a disease-specific landmark point, which may lead to a change of phase II/III clinical study design to evaluate cytotoxic agents and clinical investigators, and their sponsors may consider an early look to assess the efficacy of cytotoxic agents for NSCLC