2,262 research outputs found

    Coherent population transfer between uncoupled or weakly coupled states in ladder-type superconducting qutrits

    Get PDF
    Stimulated Raman adiabatic passage offers significant advantages for coherent population transfer between uncoupled or weakly coupled states and has the potential of realizing efficient quantum gate, qubit entanglement and quantum information transfer. Here we report on the realization of the process in the superconducting Xmon and phase qutrits—two ladder-type three-level systems in which the ground state population is coherently transferred to the second excited state via the dark state subspace. We demonstrate that the population transfer efficiency is no less than 96% and 67% for the two devices, which agree well with the numerical simulation of the master equation. Population transfer via stimulated Raman adiabatic passage is significantly more robust against variations of the experimental parameters compared with that via the conventional resonant π pulse method. Our work opens up a new venue for exploring the process for quantum information processing using the superconducting artificial atoms.This work was supported by the Ministry of Science and Technology of China (Grant Nos. 2011CBA00106, 2014CB921202, and 2015CB921104) and the National Natural Science Foundation of China (Grant Nos. 91321208, 11222437, and 11161130519). S. Han acknowledges support by the US NSF (PHY-1314861)

    Real-Time Measurement of Solute Transport Within the Lacunar-Canalicular System of Mechanically Loaded Bone: Direct Evidence for Load-Induced Fluid Flow

    Get PDF
    Since proposed by Piekarski and Munro in 1977, load-induced fluid flow through the bone lacunar-canalicular system (LCS) has been accepted as critical for bone metabolism, mechanotransduction, and adaptation. However, direct unequivocal observation and quantification of load-induced fluid and solute convection through the LCS have been lacking due to technical difficulties. Using a novel experimental approach based on fluorescence recovery after photobleaching (FRAP) and synchronized mechanical loading and imaging, we successfully quantified the diffusive and convective transport of a small fluorescent tracer (sodium fluorescein, 376 Da) in the bone LCS of adult male C57BL/6J mice. We demonstrated that cyclic end-compression of the mouse tibia with a moderate loading magnitude (–3 N peak load or 400 ”ɛ surface strain at 0.5 Hz) and a 4-second rest/imaging window inserted between adjacent load cycles significantly enhanced (+31%) the transport of sodium fluorescein through the LCS compared with diffusion alone. Using an anatomically based three-compartment transport model, the peak canalicular fluid velocity in the loaded bone was predicted (60 ”m/s), and the resulting peak shear stress at the osteocyte process membrane was estimated (∌5 Pa). This study convincingly demonstrated the presence of load-induced convection in mechanically loaded bone. The combined experimental and mathematical approach presented herein represents an important advance in quantifying the microfluidic environment experienced by osteocytes in situ and provides a foundation for further studying the mechanisms by which mechanical stimulation modulates osteocytic cellular responses, which will inform basic bone biology, clinical understanding of osteoporosis and bone loss, and the rational engineering of their treatments. © 2011 American Society for Bone and Mineral Research

    Next-to-leading order QCD predictions for Z0H0+jetZ^0 H^0 + {\rm jet} production at LHC

    Full text link
    We calculate the complete next-to-leading order (NLO) QCD corrections to the Z0H0Z^0H^0 production in association with a jet at the LHC. We study the impacts of the NLO QCD radiative corrections to the integrated and differential cross sections and the dependence of the cross section on the factorization/renormalization scale. We present the transverse momentum distributions of the final Z0Z^0-, Higgs-boson and leading-jet. We find that the NLO QCD corrections significantly modify the physical observables, and obviously reduce the scale uncertainty of the LO cross section. The QCD K-factors can be 1.183 and 1.180 at the s=14TeV\sqrt{s}=14 TeV and s=7TeV\sqrt{s}=7 TeV LHC respectively, when we adopt the inclusive event selection scheme with pT,jcut=50GeVp_{T,j}^{cut}=50 GeV, mH=120GeVm_H=120 GeV and ÎŒ=ÎŒr=ÎŒf=ÎŒ0≡1/2(mZ+mH)\mu=\mu_r=\mu_f=\mu_0 \equiv 1/2(m_Z+m_H). Furthermore, we make the comparison between the two scale choices, ÎŒ=ÎŒ0\mu=\mu_0 and ÎŒ=ÎŒ1=1/2(ETZ+ETH+∑jETjet)\mu=\mu_1=1/2(E_{T}^{Z}+E_{T}^{H}+ \sum_{j}E_{T}^{jet}), and find the scale choice ÎŒ=ÎŒ1\mu=\mu_1 seems to be more appropriate than the fixed scale ÎŒ=ÎŒ0\mu=\mu_0.Comment: 18 pages, 7 figure

    Stability and reliability of anodic biofilms under different feedstock conditions: Towards microbial fuel cell sensors

    Get PDF
    © 2015 The Authors. Stability and reliability of microbial fuel cell anodic biofilms, consisting of mixed cultures, were investigated in a continuously fed system. Two groups of anodic biofilm matured with different substrates, acetate and casein for 20-25. days, reached steady states and produced 80-87. ΌW and 20-29. ΌW consistently for 3. weeks, respectively. When the substrates were swapped, the casein-enriched group showed faster response to acetate and higher power output, compared to the acetate-enriched group. Also when the substrates were switched back to their original groups, the power output of both groups returned to the previous levels more quickly than when the substrates were swapped the first time. During the substrate change, both MFC groups showed stable power output once they reached their steady states and the output of each group with different substrates was reproducible within the same group. Community level physiological profiling also revealed the possibility of manipulating anodic biofilm metabolisms through exposure to different feedstock conditions

    New Mixed-C^N Ligand Tris-cyclometalated Ir(III) Complexes for Highly-Efficient Green Organic Light-Emitting Diodes with Low Efficiency Roll-off

    Get PDF
    This article reports new tris‐cyclometalated Ir complexes containing mixed‐C^N ligands, (C^N1)2Ir(C^N2), which are a rarely explored class of Ir(III) complexes. Two new mixed 2‐phenylpyridine (ppy) / 4‐methyl‐2,5‐diphenylpyridine (mdp) complexes (ppy)2Ir(mdp) and (ppy)Ir(mdp)2 have been synthesized and their optoelectronic properties have been systematically characterized. Photoluminescence quantum yield values are 0.76‐0.85; excited state lifetimes are 0.07‐0.11 ÎŒs. Phosphorescent organic light emitting devices (PhOLEDs) based on these emissive complexes in a very simple device architecture reproducibly showed slightly higher external quantum efficiency (EQE) and power efficiency (PE) values compared with devices using the analogous conventional homoleptic Ir complexes Ir(ppy)3 and Ir(mdp)3, and the heteroleptic complexes (ppy)2Ir(acac) and (mdp)2Ir(acac). The new complexes (ppy)2Ir(mdp) 3 and (ppy)Ir(mdp)2 4 give PhOLEDs with EQEmax and PEmax values of 26.7 and 26.0% / 94.7 and 94.1 lm W−1, respectively, and very high values are retained at the practical luminances of 100 and 1000 cd m−2. The values for (ppy)2Ir(mdp) are 26.3% and 73.6 lm W−1 (at 100 cd m−2) and 24.6% and 53.5 lm W−1 (at 1000 cd m−2). These efficiencies are comparable with the highest reported values of PhOLEDs using conventional Ir(III) emitters in more complicated device structures. Mixed C^N ligand systems are, therefore, a viable strategy for developing new efficient phosphorescent emitters

    Bullae and Sweat Gland Necrosis in the Differential Diagnosis for Vibrio vulnificus Infection in an Alcoholic Patient

    Get PDF
    Bullae and sweat gland necrosis remain rare cutaneous manifestation, and these conditions can be misdiagnosed as Vibrio vulnificus infections or other soft tissue infections because of their low index of suspicion. A 46-yr-old man with a history of continued alcohol consumption presented with erythematous and hemorrhagic bullous lesions on his left arm. The patient reported that after the ingestion of clams, he slept for 12 hr in a heavily intoxicated state. Then the skin lesions started as a reddish patch that subsequently became hemorrhagic bullae. V. vulnificus infection, cellulitis, and necrotizing fasciitis were considered in initial differential diagnosis. However, on the basis of sweat gland necrosis on histopathologic examinations and negative results on bacterial cultures, we made the diagnosis of bullae and sweat gland necrosis. Therefore, bullae and sweat gland necrosis should also be considered in chronic alcoholic patients who present with bullae and a previous history of unconsciousness
    • 

    corecore