1,602 research outputs found
Negativity volume of the generalized Wigner function in gravitating hybrid system
We evaluate the gravity-induced negativity volume of the generalized Wigner
function in a hybrid system consisting of a particle in a two-localized
superposition state and an oscillator. The generalized Wigner function can
capture the nonclassicality of the system. The increase in the negativity
volume of the generalized Wigner function can be an indicator of the
entanglement generation, which is demonstrated in the hybrid system generating
the gravity-induced entanglement in various initial states. Moreover, by
comparing the behaviors of the negativity volume with the entanglement
fidelity, we show that the nonclassical feature of entanglement is properly
identified by the criterion based on the negativity volume of the generalized
Wigner function when the oscillator is initially in a thermal state.Comment: 12 pages, 5 figure
Quantitative Analysis of DNA Degradation in the Dead Body
Postmortem degradation of DNA was quantitatively estimated. Brain, liver, kidney and muscle samples were obtained from sacrificed rats left at 20℃ or 4℃. The quantity of DNA was measured by real-time PCR using a primer set for a sequence in the Rsrc 1 gene. When the quantity of amplified DNA using 10ng Human Genomic DNA was defined as 100 RFU, the quantities in the brain, liver, kidney and skeletal muscle (each 2μg of dry weight) on the day of sacrifice were 253±11, 338±22, 556±14 and 531±12 Relative Fluorescence Units (RFU), respectively (mean±S.E., n=5). The quantity of amplified DNA decreased to below 10 RFU in 1-3 weeks in the liver, kidney and skeletal muscle at 20℃, while that in the brain was more than 10 RFU for six weeks, demonstrating the usefulness of the brain as a sample for DNA analysis of decaying corpses. It was suggested that quantifying the amplified DNA in the brain at 20℃ and in the liver at 4℃ as well as the ratio of the quantity of amplified DNA in the liver to the brain at 4℃ might be useful for diagnosing time of death. This study provides the first quantitative analysis of the postmortem progress of DNA degradation in the corpse
Generating quantum entanglement between macroscopic objects with continuous measurement and feedback control
This study is aimed at investigating the feasibility of generating quantum
entanglement between macroscopic mechanical mirrors in optomechanical systems
while under continuous measurement and feedback control. We carefully derive a
covariance matrix for mechanical mirrors in a steady state, employing the
Kalman filtering problem with an assumed dominant cavity photon dissipation,
such that the common and differential modes of the mirrors are squeezed by the
action of measuring the output light beams. We demonstrate that entanglement
between the mechanical mirrors is generated when the states of the common and
differential modes are squeezed with high purity in an asymmetric manner. Our
results also show that quantum entanglement between mg mirrors is
achievable in the short term.Comment: 20 pages, 10 figure
Reports of Studies supported by Grant-in-Aid for Research from the Graduate School of Biosphere Science, Hiroshima University
基盤研究サポート Grant-in-Aid for Fundamental Research
・流域圏スケールでの水質および水量の管理に関する国際比較研究…山本民次
・育成前期乳用牛の夏季暑熱への順応に関する研究…沖田美
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