A new power-efficient, reconfigurable, 6-order continuous-time bandpass delta-sigma modulator architecture is presented. A new duty-cycle-controlled DAC halves the number of DACs in the modulator, and also enables the center frequency to be reconfigurable. A prototype 800MS/s modulator achieves 69dB SNDR with a 25MHz bandwidth at a 200MHz IF. The center frequency can be varied from 180MHz to 22...

By spectrally and temporally reshaping the gain-window of a traveling-wave semiconductor optical amplifier (TWSOA) with a backward injected multi- or single-wavelength inverse-optical-comb, we theoretically and experimentally investigate the dynamic frequency chirp of the all-optical 10GBit/s Return-to-Zero (RZ) data-stream format-converted from the TWSOA under strong cross-gain depletion schem...

We demonstrate the conversion of a nonreturn-to-zero (NRZ)-formatted electrical data stream into a wavelength-tunable return-to-zero (RZ)-formatted optical pulse code by externally seeding a synchronously sinusoidal-modulated Fabry-Perot laser diode (FPLD) with optical pseudorandom binary-sequence data at 10 Gbits/s (Gbps). The FPLD without a dc-biased current was modulated by use of a power-am...

The majority of the citriculture in Brazil is located in the state of São Paulo, with a total production area of 700,000 ha. Trees are grafted mostly on ‘Rangpur’ lime (RL; Citrus limonia Osbeck) rootstock. Despite its good horticultural performance, use of other rootstocks has increased with the search for disease-tolerant varieties to improve grove productivity and longevity. Furthermore, the...

acetone fractionated peroxidase from crude extract of brassica oleracea leaves (cabbage) was purified in three steps on chromatographic columns, using sp-sepharose, deae-sepharose and con a-sepharose. the specific activity of purified main isoenzyme (boc-pod) is 1887 u/mg protein with rz: 3.1, which is 172 times more than the rz of crude extract with 4.3% recovery. the molecular weight of boc-p...

Human tumor cell progression and metastasis are partially dependent on the ability of a tumor cell to adhere to the proteins of the extracellular matrix (ECM) and survive at the distant location. Six novel D-amino acid-containing peptides were analyzed for their ability to adhere to human prostate tumor cells, support tumor cell adhesion, and inhibit tumor cell adhesion to ECM proteins or human...

To test the hypothesis that cortical remapping supports phantom sensations, we examined referred phantom sensations and cortical activation in humans after spinal-cord injury (SCI) at the thoracic level (T3-T12). Of 12 SCI subjects, 9 reported phantom sensations, and 2 reported referred phantom sensations. In both of these subjects, referred phantom sensations were evoked by contact in referenc...

tolerance of two apple rootstocks (gami and m26) was evaluated at different concentrations of sodium chloride in vitro conditions. micro plants grown under ms medium culture were transferred to knoudson–c culture medium devoid of na and cl ions. concentrations of nacl in the knoudson-c culture medium were 0, 20, 40, 60, 80 and 100 mm/l. six weeks after culturing, data were collected. the result...

Greenhouse-grown l-year-old sweet orange trees [Citrus sinensis (L.) Osbeck cv. Valencia] on cold-hardy trifoliate orange [Poncirus trifoliata (L.) Raf.] and cold-sensitive citron (C. medica L.) rootstocks were exposed to cold-acclimation conditions and freeze-tested at -6.7C for 4 hours in a temperature-programed walk-in freezer room. Nonhardened trees generally did not survive the freeze, whe...

Return-to-Zero (RZ) and Non-Return-to-Zero (NRZ) Differential Phase Shift Keyed (DPSK) systems require cheap and optimal transmitters for widespread implementation. The authors report on a gain switched Discrete Mode (DM) laser that can be employed as a cost efficient transmitter in a 10.7 Gb/s RZ DPSK system and compare its performance to that of a gain switched Distributed Feed-Back (DFB) las...