254 research outputs found
Correlated Errors in Quantum Error Corrections
We show that errors are not generated correlatedly provided that quantum bits
do not directly interact with (or couple to) each other. Generally, this
no-qubits-interaction condition is assumed except for the case where two-qubit
gate operation is being performed. In particular, the no-qubits-interaction
condition is satisfied in the collective decoherence models. Thus, errors are
not correlated in the collective decoherence. Consequently, we can say that
current quantum error correcting codes which correct single-qubit-errors will
work in most cases including the collective decoherence.Comment: no correction, 3 pages, RevTe
Meson Exchange Currents in (e,e'p) recoil polarization observables
A study of the effects of meson-exchange currents and isobar configurations
in reactions is presented. We use a distorted wave
impulse approximation (DWIA) model where final-state interactions are treated
through a phenomenological optical potential. The model includes relativistic
corrections in the kinematics and in the electromagnetic one- and two-body
currents. The full set of polarized response functions is analyzed, as well as
the transferred polarization asymmetry. Results are presented for proton
knock-out from closed-shell nuclei, for moderate to high momentum transfer.Comment: 44 pages, 18 figures. Added physical arguments explaining the
dominance of OB over MEC, and a summary of differences with previous MEC
calculations. To be published in PR
Channel Coupling in Reactions
The sensitivity of momentum distributions, recoil polarization observables,
and response functions for nucleon knockout by polarized electrons to channel
coupling in final-state interactions is investigated using a model in which
both the distorting and the coupling potentials are constructed by folding
density-dependent effective interactions with nuclear transition densities.
Calculations for O are presented for 200 and 433 MeV ejectile energies,
corresponding to proposed experiments at MAMI and TJNAF, and for C at 70
and 270 MeV, corresponding to experiments at NIKHEF and MIT-Bates. The relative
importance of charge exchange decreases as the ejectile energy increases, but
remains significant for 200 MeV. Both proton and neutron knockout cross
sections for large recoil momenta, MeV/c, are substantially
affected by inelastic couplings even at 433 MeV. Significant effects on the
cross section for neutron knockout are also predicted at smaller recoil
momenta, especially for low energies. Polarization transfer for proton knockout
is insensitive to channel coupling, even for fairly low ejectile energies, but
polarization transfer for neutron knockout retains nonnegligible sensitivity to
channel coupling for energies up to about 200 MeV. The present results suggest
that possible medium modifications of neutron and proton electromagnetic form
factors for can be studied using recoil
polarization with relatively little sensitivity due to final state
interactions.Comment: Substantially revised version accepted by Phys. Rev. C; shortened to
49 pages including 21 figure
IDegLira Improves Both Fasting and Postprandial Glucose Control as Demonstrated Using Continuous Glucose Monitoring and a Standardized Meal Test
Objective: IDegLira is a novel, fixed-ratio combination of the long-acting basal insulin, insulin degludec, and the long-acting glucagon-like peptide-1 analog liraglutide. We studied the effect of IDegLira versus its components on postprandial glucose (PPG) in type 2 diabetes. Methods: In this substudy, 260 (15.6%) of the original 1663 patients with inadequate glycemic control participating in a 26-week, open-label trial (DUAL I) were randomized 2:1:1 to once-daily IDegLira, insulin degludec or liraglutide. Continuous glucose monitoring (CGM) for 72 hours and a meal test were performed. Results: At week 26, IDegLira produced a significantly greater decrease from baseline in mean PPG increment (normalized iAUC0-4h) than insulin degludec (estimated treatment difference [ETD] -'12.79 mg/dl [95% CI: -'21.08; -'4.68], P =.0023) and a similar magnitude of decrease as liraglutide (ETD -'1.62 mg/dl [95% CI: -'10.09; 6.67], P =.70). CGM indicated a greater reduction in change from baseline in PPG increment (iAUC0-4h) for IDegLira versus insulin degludec over all 3 main meals (ETD -'6.13 mg/dl [95% CI: -'10.27, -'1.98], P =.0047) and similar reductions versus liraglutide (ETD -'1.80 mg/dl [95% CI: -'2.52, 5.95], P =.4122). Insulin secretion ratio and static index were greater for IDegLira versus insulin degludec (P =.048 and P =.006, respectively) and similar to liraglutide (P =.45 and P =.895, respectively). Conclusions: Once-daily IDegLira provides significantly better PPG control following a mixed meal test than insulin degludec. The improvement is at least partially explained by higher endogenous insulin secretion and improved beta cell function with IDegLira. The benefits of liraglutide on PPG control are maintained across all main meals in the combination
Polarization transfer in the HeH reaction
Polarization transfer in the 4He(e,e'p)3H reaction at a Q^2 of 0.4 (GeV/c)^2
was measured at the Mainz Microtron MAMI. The ratio of the transverse to the
longitudinal polarization components of the ejected protons was compared with
the same ratio for elastic ep scattering. The results are consistent with a
recent fully relativistic calculation which includes a predicted medium
modification of the proton form factor based on a quark-meson coupling model.Comment: 5 pages, Latex, 2 postscript figures, submitted to Physics Letters
Experimental investigation of the detection mechanism in WSi nanowire superconducting single photon detectors
Quantum Matter and Optic
Microwave assisted synthesis of novel bis-flavone dimers as new anticancer agents
In this study we describe a microwave based click chemistry method used to prepare a family of novel bis-flavone dimers. The substituted 7-hydroxy and 4’-hydroxy flavonoids were linked through a triazole ring. The compounds were easily synthesized and purified in high yields. The bis-flavonoids were tested on different cell lines including HCT116, HepG2, MCF7 and MOLT-4. Several analogues showed to have anticancer activity with IC50 values in the range of 20-60 µM. Flavonoids are known for their anticancer properties and this method provides the basis for new medicinal structures
Interannual active layer variability at the Limnopolar Lake CALM site on Byers Peninsula, Livingston Island, Antarctica
Regional cerebral blood flow alterations in obstructive sleep apnea
Obstructive sleep apnea (OSA) is a condition characterized by upper airway muscle atonia with continued diaphragmatic efforts, resulting in repeated airway obstructions, periods of intermittent hypoxia, large thoracic pressure changes, and substantial shifts in arterial pressure with breathing cessation and resumption. The hypoxic exposure and hemodynamic changes likely induce the structural and functional deficits found in multiple brain areas, as shown by magnetic resonance imaging (MRI) procedures. Altered cerebral blood flow (CBF) may contribute to these localized deficits; thus, we examined regional CBF, using arterial spin labeling procedures, in 11 OSA (age, 49.1±12.2 years; 7 male) and 16 control subjects (42.3±10.2 years; 6 male) with a 3.0-Tesla MRI scanner. CBF maps were calculated, normalized to a common space, and regional CBF values across the brain quantified. Lowered CBF values emerged near multiple bilateral brain sites in OSA, including the corticospinal tracts, superior cerebellar peduncles, and pontocerebellar fibers. Lateralized, decreased CBF appeared near the left inferior cerebellar peduncles, left tapetum, left dorsal fornix/stria terminalis, right medial lemniscus, right red nucleus, right midbrain, and midline pons. Regional CBF values in OSA are significantly reduced in major sensory and motor fiber systems and motor regulatory sites, especially in structures mediating motor coordination; those reductions are often lateralized. The asymmetric CBF declines in motor regulatory areas may contribute to loss of coordination between upper airway and diaphragmatic musculature, and lead to further damage in the syndrome
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