4,552 publications from this institution
A significant inhibition of the growth of adenocarcinoma 755 tumors in BDF1 mice was effected by oral tegafur (FT) in combination with oral (E)-5-(2-bromovinyl)-2'-deoxyuridine (BVdUrd), at doses at which neither drug used alone had antitumor activity. The maximum inhibition of tumor growth (97%) was achieved by using a combination of 50 mg FT/kg with 10 mg BVdUrd/kg but, even at a dose as low as 1 mg BVdUrd/kg, the antitumor potency of FT was enhanced. The effect which BVdUrd has on the antitumor potency of FT is apparently due to inhibitory action by bromovinyluracil, the phosphorolytic product of BVdUrd, on the degradation of 5-fluorouracil, the oxidative product of FT, by dihydrothymine dehydrogenase.
We report a high-performance pulsed coherent population trapping (CPT) Cs cell atomic clock using the implementation of a symmetric auto-balanced Ramsey (SABR) interrogation sequence. The latter method is found to reduce the light-power induced frequency shift by an order of magnitude compared to a previous experiment using a simple auto-balanced Ramsey interrogation. The contribution of this shift to the clock frequency stability is now rejected in the 10−16 range at 104 s averaging time. Additional tricks, including a compensation method to reduce the laser amplitude noise contribution and the generation of novel error signals for local oscillator frequency and phase correction, have been implemented using a FPGA-based digital electronics board in order to improve the clock short-term stability by a of factor 2. The Allan deviation of the SABR-CPT clock, extracted from a selected 3 × 104 s-long dataset, is 2 × 10−13 τ−1∕2 and averages down to the level of 2.5 × 10−15 at 104 s. These results are encouraging to stimulate the development of hot cell CPT-based clocks for industrial, scientific, and instrumentation applications.
