283 research outputs found
A test of "fluctuation theorem" in non-Markovian open quantum systems
We study fluctuation theorems for open quantum systems with a non-Markovian
heat bath using the approach of quantum master equations and examine the
physical quantities that appear in those fluctuation theorems. The approach of
Markovian quantum master equations to the fluctuation theorems was developed by
Esposito and Mukamel [Phys. Rev. E {\bf73}, 046129 (2006)]. We show that their
discussion can be formally generalized to the case of a non-Markovian heat bath
when the local system is linearly connected to a Gaussian heat bath with the
spectrum distribution of the Drude form. We found by numerically simulating the
spin-boson model in non-Markovian regime that the "detailed balance" condition
is well satisfied except in a strongly non-equilibrium transient situation, and
hence our generalization of the definition of the "entropy production" is
almost always legitimate. Therefore, our generalization of the fluctuation
theorem seems meaningful in wide regions.Comment: 21 pages, 5 figure
Geometrical Pumping in Quantum Transport: Quantum Master Equation Approach
For an open quantum system, we investigate the pumped current induced by a
slow modulation of control parameters on the basis of the quantum master
equation and full counting statistics. We find that the average and the
cumulant generating function of the pumped quantity are characterized by the
geometrical Berry-phase-like quantities in the parameter space, which is
associated with the generator of the master equation. From our formulation, we
can discuss the geometrical pumping under the control of the chemical
potentials and temperatures of reservoirs. We demonstrate the formulation by
spinless electrons in coupled quantum dots. We show that the geometrical
pumping is prohibited for the case of non-interacting electrons if we modulate
only temperatures and chemical potentials of reservoirs, while the geometrical
pumping occurs in the presence of an interaction between electrons
Microscopic analysis of the microscopic reversibility in quantum systems
We investigate the robustness of the microscopic reversibility in open
quantum systems which is discussed by Monnai [arXiv:1106.1982 (2011)]. We
derive an exact relation between the forward transition probability and the
reversed transition probability in the case of a general measurement basis. We
show that the microscopic reversibility acquires some corrections in general
and discuss the physical meaning of the corrections. Under certain processes,
some of the correction terms vanish and we numerically confirmed that the
remaining correction term becomes negligible; the microscopic reversibility
almost holds even when the local system cannot be regarded as macroscopic.Comment: 12 pages, 10 figure
Polarised target for Drell-Yan experiment in COMPASS at CERN, part I
In the polarised Drell-Yan experiment at the COMPASS facility in CERN pion
beam with momentum of 190 GeV/c and intensity about pions/s interacted
with transversely polarised NH target. Muon pairs produced in Drel-Yan
process were detected. The measurement was done in 2015 as the 1st ever
polarised Drell-Yan fixed target experiment. The hydrogen nuclei in the
solid-state NH were polarised by dynamic nuclear polarisation in 2.5 T
field of large-acceptance superconducting magnet. Large helium dilution
cryostat was used to cool the target down below 100 mK. Polarisation of
hydrogen nuclei reached during the data taking was about 80 %. Two oppositely
polarised target cells, each 55 cm long and 4 cm in diameter were used.
Overview of COMPASS facility and the polarised target with emphasis on the
dilution cryostat and magnet is given. Results of the polarisation measurement
in the Drell-Yan run and overviews of the target material, cell and dynamic
nuclear polarisation system are given in the part II.Comment: 4 pages, 2 figures, Proceedings of the 22nd International Spin
Symposium, Urbana-Champaign, Illinois, USA, 25-30 September 201
Formation of two-dimensional weak localization in conducting Langmuir-Blodgett films
We report the magnetotransport properties up to 7 T in the organic highly
conducting Langmuir-Blodgett(LB) films formed by a molecular association of the
electroactive donor molecule bis(ethylendioxy)tetrathiafulvalene (BEDO-TTF) and
stearic acid CH(CH)COOH. We show the logarithmic decrease of dc
conductivity and the negative transverse magnetoresistance at low temperature.
They are interpreted in the weak localization of two-dimensional (2D)
electronic system based on the homogeneous conducting layer with the molecular
size thickness of BEDO-TTF. The electronic length with phase memory is given at
the mesoscopic scale, which provides for the first time evidence of the 2D
coherent charge transport in the conducting LB films.Comment: 5 pages, 1 Table and 5 figure
Successful closure of spontaneous esophageal rupture (Boerhaave’s syndrome) by endoscopic ligation with snare loops
A Conditional Deletion of the NR1 Subunit of the NMDA Receptor in Adult Spinal Cord Dorsal Horn Reduces NMDA Currents and Injury-Induced Pain
To determine the importance of the NMDA receptor (NMDAR) in pain hypersensitivity after injury, the NMDAR1 (NR1) subunit was selectively deleted in the lumbar spinal cord of adult mice by the localized injection of an adenoassociated virus expressing Cre recombinase into floxed NR1 mice. NR1 subunit mRNA and dendritic protein are reduced by 80% in the area of the virus injection, and NMDA currents, but not AMPA currents, are reduced 86–88% in lamina II neurons. The spatial NR1 knock-out does not alter heat or cold paw-withdrawal latencies, mechanical threshold, or motor function. However, injury-induced pain produced by intraplantar formalin is reduced by 70%. Our results demonstrate conclusively that the postsynaptic NR1 receptor subunit in the lumbar dorsal horn of the spinal cord is required for central sensitization, the central facilitation of pain transmission produced by peripheral injury
One-year results of a multicenter controlled clinical trial of triamcinolone in pars plana vitrectomy
Plasma pharmacokinetics after combined therapy of gemcitabine and oral S-1 for unresectable pancreatic cancer
<p>Abstract</p> <p>Background</p> <p>The combination of gemcitabine (GEM) and S-1, an oral 5-fluorouracil (5-FU) derivative, has been shown to be a promising regimen for patients with unresectable pancreatic cancer.</p> <p>Methods</p> <p>Six patients with advanced pancreatic cancer were enrolled in this pharmacokinetics (PK) study. These patients were treated by oral administration of S-1 30 mg/m<sup>2 </sup>twice daily for 28 consecutive days, followed by a 14-day rest period and intravenous administration of GEM 800 mg/m<sup>2 </sup>on days 1, 15 and 29 of each course. The PK parameters of GEM and/or 5-FU after GEM single-administration, S-1 single-administration, and co-administration of GEM with pre-administration of S-1 at 2-h intervals were analyzed.</p> <p>Results</p> <p>The maximum concentration (Cmax), the area under the curve from the drug administration to the infinite time (AUCinf), and the elimination half-life (T1/2) of GEM were not significantly different between GEM administration with and without S-1. The Cmax, AUCinf, T1/2, and the time required to reach Cmax (Tmax) were not significantly different between S-1 administration with and without GEM.</p> <p>Conclusion</p> <p>There were no interactions between GEM and S-1 regarding plasma PK of GEM and 5-FU.</p
- …