3,369 research outputs found
Phase-Resolved Timing Analysis of GRS 1915+105 in Its {\rho} State
We made a phase-resolved timing analysis of GRS 1915+105 in its {\rho} state
and obtained detailed {\rho} cycle evolutions of the frequency, the amplitude
and the coherence of low-frequency quasi-periodic oscillation (LFQPO). We
combined our timing results with the spectral study by Neilsen et al. to
perform an elaborate comparison analysis. Our analyses show that the LFQPO
frequency does not scale with the inner disk radius, but it is related to the
spectral index, indicating a possible correlation between the LFQPOs and the
corona. The LFQPO amplitude spectrum and other results are naturally explained
by tying the LFQPO to the corona. The similarities of the spectra of
variability parameters between the LFQPO from {\rho} state and those from more
steady states indicate that the LFQPOs of GRS 1915+105 in very different states
seem to share the same origin.Comment: 21 pages, 4 figures, accepted for publication in Ap
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A Network Stability Monitoring Mechanism of Cluster-Oriented Wireless Sensor Network
In wireless sensor network (WSN), every sensor node could active dynamically. Therefore, those sensor nodes will affect the stability of network topology because of clustering and de-clustering, and continuously make reconfiguration for the clusters of wireless sensor network, all that will influence the overall function of network. It is an important issue that how to elect a cluster manager (CM) to keep the stability of network topology. In addition, large amount of events maybe flood suddenly in a local area. Such the case might raise the overload of CM, even lead CM to fail or crash and the WSN topology maybe self-organized. However, a mechanism needs to be considered that allows coping with the additional loads and can balance the workload of CM. In this study, a preventable and supportable monitor mechanism to avoid CM overload cause network unstable and to reduce load imbalance problem is proposed. Hence, it can prolong lifetime of network and raise performance of network efficiently
Large-deviation analysis for counting statistics in mesoscopic transports
We present an efficient approach, based on a number-conditioned master
equation, for large-deviation analysis in mesoscopic transports. Beyond the
conventional full-counting-statistics study, the large-deviation approach
encodes complete information of both the typical trajectories and the rare
ones, in terms of revealing a continuous change of the dynamical phase in
trajectory space. The approach is illustrated with two examples: (i) transport
through a single quantum dot, where we reveal the inhomogeneous distribution of
trajectories in general case and find a particular scale invariance point in
trajectory statistics; and (ii) transport through a double dots, where we find
a dynamical phase transition between two distinct phases induced by the Coulomb
correlation and quantum interference.Comment: 8 pages, 3 figure
Insights into the Ecological Roles and Evolution of Methyl-Coenzyme M Reductase-Containing Hot Spring Archaea
Several recent studies have shown the presence of genes for the key enzyme associated with archaeal methane/alkane metabolism, methyl-coenzyme M reductase (Mcr), in metagenome-assembled genomes (MAGs) divergent to existing archaeal lineages. Here, we study the mcr-containing archaeal MAGs from several hot springs, which reveal further expansion in the diversity of archaeal organisms performing methane/alkane metabolism. Significantly, an MAG basal to organisms from the phylum Thaumarchaeota that contains mcr genes, but not those for ammonia oxidation or aerobic metabolism, is identified. Together, our phylogenetic analyses and ancestral state reconstructions suggest a mostly vertical evolution of mcrABG genes among methanogens and methanotrophs, along with frequent horizontal gene transfer of mcr genes between alkanotrophs. Analysis of all mcr-containing archaeal MAGs/genomes suggests a hydrothermal origin for these microorganisms based on optimal growth temperature predictions. These results also suggest methane/alkane oxidation or methanogenesis at high temperature likely existed in a common archaeal ancestor
Phase I Trial of Escalating-dose Cisplatin with 5-fluorouracil and Concurrent Radiotherapy in Chinese Patients with Esophageal Cancer
We defined the maximum-tolerated dose (MTD) of chemoradiotherapy (cisplatin (CDDP) with 5-fluorouracil
(5-FU) and concurrent chemoradiotherapy) for Chinese patients with esophageal cancer. Twenty-one previously untreated patients with primary esophageal cancer were entered into this study. Escalating doses of CDDP with 5-FU were administered in a modified Fibonacci sequence, with
concurrent conventional fractionation radiotherapy (CFR) of 60 Gy or 50 Gy. The starting doses were CDDP 37.5 mg/m2 on day 1, and 5-FU 500 mg/m2 on days 1-5, respectively. The regimen was repeated 4 times every 28 days. If no dose-limiting toxicity (DLT) was observed, the next dose level
was applied. The procedures were repeated until DLT appeared. The MTD was declared to be 1 dose level below the level at which DLT appeared. DLT was grade 3 radiation-induced esophagitis at a dose level of CDDP 60 mg/m2 with 5-FU 700 mg/m2 and concurrent 60 Gy CFR. MTD was defined as CDDP 52.5 mg/m2 with 5-FU 700 mg/m2 and concurrent 50 Gy CFR. The MTD of CDDP with 5-FU and in concurrent chemoradiotherapy for Chinese patients with esophageal cancer is CDDP 52.5 mg/m2 on day 1 and 5FU 700 mg/m2 on days 1-5, repeated 4 times every 28 days, and concurrent 50 Gy CFR. Further evaluation of this regimen in a prospective phase II trial is ongoing.</p
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