242 research outputs found
Period doubling eigenstates in a fiber laser mode-locked by nonlinear polarization rotation
Due to the weak birefringence of single mode fibers, solitons generated in
fiber lasers are indeed vector pulses and exhibit periodic parameter change
including polarization evolution even when there is a polarizer inside the
cavity. Period doubling eigenstates of solitons generated in a fiber laser
mode-locked by the nonlinear polarization rotation, i.e., period doubling of
polarization components of the soliton, are numerically explored in detail. We
found that, apart from the synchronous evolution between the two polarization
components, there exists asynchronous development depending on the detailed
operation conditions. In addition, period doubling of one polarization
component together with period-one of another polarization component can be
achieved. When the period tripling window is obtained, much complexed dynamics
on the two polarization components could be observed.Comment: 6 page
IL-6 production in ovarian carcinoma is associated with histiotype and biological characteristics of the tumour and influences local immunity
The presence of interleukin (IL)-6 in peritoneal carcinomatous fluid (PCF) and its effect on immune cells composition in PCF in patients with advanced ovarian carcinoma was studied. In 21 out of 30 ovarian carcinoma patients, PCF IL-6 levels were found to exceed those seen in PCFs of patients with gastrointestinal cancer. IL-6 activity was higher in serous/mucinous than in endometrioid and undifferentiated ovarian carcinoma PCF (P = 0.05). Ovarian carcinoma PCF IL-6 activities were correlated with serum C-reactive protein levels (r = 0.65, P = 0.0000, n = 25). Ovarian carcinoma PCF leucocyte profile differed from that in blood with respect to: (i) lower percentage of NK and CD8+and (ii) higher percentage of B and CD45RO+, CD14+and HLA-DR+cells. The proportions of CD45RO+in blood were correlated with IL-6 levels in PCF. Corresponding to PCF ovarian carcinoma tumours were stained for the presence of Ki-67 antigen and p53. The highest proportions of Ki-67+cells and cells showing accumulation of p53 were seen in undifferentiated tumours. A low grade of p53 staining was seen in tumours associated with high IL-6 levels in PCF. It was evident that IL-6 production (i) depended on the histiotype of the tumour, (ii) influenced the local immune system in favour of accumulation of B, and T memory cells, and (iii) was higher in patients lacking p53 accumulation. © 2000 CancerResearch Campaig
Period doubling of multiple dissipative-soliton-resonance pulses in a fibre laser
We report on the experimental observation of the period doubling of multiple dissipative-soliton-resonance (DSR) pulses in an all-normal-dispersion fibre laser, based on a nonlinear amplifying loop mirror. By increasing the pump power, the transition from a single DSR pulse to multiple DSR pulses was observed, in addition to the typical linear pulse broadening, under a fixed pulse peak power. During this process, period doubling appeared because the DSR pulses can exhibit the characteristics of period doubling in a multi-pulse state. The typical DSR performance of a linear pulse duration change, versus the variation of pump power, can be maintained when the period doubling of multiple DSR pulses appears
Breach and recurrence of dissipative soliton resonance during period-doubling evolution in a fiber laser
We report on the experimental observation of period-doubling bifurcation of
dissipative-soliton-resonance (DSR) pulses in a fiber laser passively
mode-locked by using the nonlinear optical loop mirror. Increasing the pump
power of the fiber laser, we show that temporally a stable, uniform DSR pulse
train could be transformed into a period-doubling state, exhibiting two sets of
pulse parameters between the adjacent cavity roundtrip. It is found that DSR
pulses in the period-doubling state could maintain the typical feature of DSR
pulse: fixed pulse peak power and linear variation in pulse width with respect
to the pump power change. The mechanism for achieving period-doubling of DSR
pulses is discussed.Comment: 9 page
A conserved phosphorylation site regulates the transcriptional function of ETHYLENE-INSENSITIVE3-like1 in tomato
ETHYLENE-INSENSITIVE3/ETHYLENE-INSENSITIVE3-like (EIN3/EIL) transcription factors are important downstream components of the ethylene transduction pathway known to regulate the transcription of early ethylene-responsive genes in plants. Previous studies have shown that phosphorylation can repress their transcriptional activity by promoting protein degradation. The present study identifies a new phosphorylation region named EPR1 (EIN3/EIL phosphorylation region 1) in tomato EIL1 proteins. The functional significance of EPR1 was tested by introducing mutations in this region of the Sl-EIL1 gene and by expressing these mutated versions in transgenic tomato plants. Transient expression data and phenotypic analysis of the transgenic lines indicated that EPR1 is essential for the transcriptional activity of Sl-EIL1. Moreover, mutation in the EPR1 site that prevents phosphorylation abolishes ethylene constitutive responses normally displayed by the Sl-EIL1-overexpressing lines. Bimolecular fluorescence complementation (BiFC) studies showed that the presence of a functional phosphorylation site within EPR1 is instrumental in the dimerization of Sl-EIL1 proteins. The results illuminate a new molecular mechanism for the control of EIN3/EIL activity and propose a model where phosphorylation within the EPR1 promotes the dimerization process allowing the initiation of EIL-mediated transcription of early ethylene-regulated genes
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Insights into the subsurface structure of the Caloris basin, Mercury, from assessments of mechanical layering and changes in long-wavelength topography
The volcanic plains that fill the Caloris basin, the largest recognized impact basin on Mercury, are deformed by many graben and wrinkle ridges, among which the multitude of radial graben of Pantheon Fossae allow us to resolve variations in the depth extent of associated faulting. Displacement profiles and displacement-to-length scaling both indicate that faults near the basin center are confined to a ~ 4-km-thick mechanical layer, whereas faults far from the center penetrate more deeply. The fault scaling also indicates that the graben formed in mechanically strong material, which we identify with dry basalt-like plains. These plains were also affected by changes in long-wavelength topography, including undulations with wavelengths of up to 1300 km and amplitudes of 2.5 to 3 km. Geographic correlation of the depth extent of faulting with topographic variations allows a first-order interpretation of the subsurface structure and mechanical stratigraphy in the basin. Further, crosscutting and superposition relationships among plains, faults, craters, and topography indicate that development of long-wavelength topographic variations followed plains emplacement, faulting, and much of the cratering within the Caloris basin. As several examples of these topographic undulations are also found outside the basin, our results on the scale, structural style, and relative timing of the topographic changes have regional applicability and may be the surface expression of global-scale interior processes on Mercury
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Insights into the subsurface structure of the Caloris basin, Mercury, from assessments of mechanical layering and changes in long-wavelength topography
The volcanic plains that fill the Caloris basin, the largest recognized impact basin on Mercury, are deformed by many graben and wrinkle ridges, among which the multitude of radial graben of Pantheon Fossae allow us to resolve variations in the depth extent of associated faulting. Displacement profiles and displacement-to-length scaling both indicate that faults near the basin center are confined to a ~ 4-km-thick mechanical layer, whereas faults far from the center penetrate more deeply. The fault scaling also indicates that the graben formed in mechanically strong material, which we identify with dry basalt-like plains. These plains were also affected by changes in long-wavelength topography, including undulations with wavelengths of up to 1300 km and amplitudes of 2.5 to 3 km. Geographic correlation of the depth extent of faulting with topographic variations allows a first-order interpretation of the subsurface structure and mechanical stratigraphy in the basin. Further, crosscutting and superposition relationships among plains, faults, craters, and topography indicate that development of long-wavelength topographic variations followed plains emplacement, faulting, and much of the cratering within the Caloris basin. As several examples of these topographic undulations are also found outside the basin, our results on the scale, structural style, and relative timing of the topographic changes have regional applicability and may be the surface expression of global-scale interior processes on Mercury
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