3,003 research outputs found
Bayesian credible interval construction for Poisson statistics
The construction of the Bayesian credible (confidence) interval for a Poisson
observable including both the signal and background with and without systematic
uncertainties is presented. Introducing the conditional probability satisfying
the requirement of the background not larger than the observed events to
construct the Bayesian credible interval is also discussed. A Fortran routine,
BPOCI, has been developed to implement the calculation.Comment: 7 pages, 1 figur
Nonlocal Gate Of Quantum Network Via Cavity Quantum Electrodynamics
We propose an experimentally feasible scheme to realize the nonlocal gate
between two different quantum network nodes. With an entanglement-qubit (ebit)
acts as a quantum channel, our scheme is resistive to actual environment noise
and can get high fidelity in current cavity quantum electrodynamics (C-QED)
system.Comment: 5 pages, 3 figures, 1 tabl
Comment on "Quantum key distribution without alternative measurements"
In a recent paper [A. Cabello, Phys. Rev. A 61, 052312 (2000)], a quantum key
distribution protocol based on entanglement swapping was proposed. However, in
this comment, it is shown that this protocol is insecure if Eve use a special
strategy to attack.Comment: 2 Pages, 1 Figur
Recording sympathetic nerve activity from the skin
Sympathetic tone is important in cardiac arrhythmogenesis; however, methods to estimate sympathetic tone are either invasive or require proper sinus node function that may be abnormal in disease states. Because of the direct and extensive connections among various nerve structures, it is possible for the sympathetic nerves in the various structures to activate simultaneously. Therefore, we hypothesized that nerve activity can be recorded from the skin and it can be used to estimate the cardiac sympathetic tone. Preclinical studies in canines demonstrated that nerve activity is detectable using conventional ECG electrodes and can be used to estimate cardiac sympathetic tone. Subsequent clinical studies further supported this concept. In addition to studying the autonomic mechanisms of cardiac arrhythmia, these new methods may have broad application in studying both cardiac and non-cardiac diseases
Experimental realization of large-alphabet quantum key distribution protocol using orbital angular momentum entanglement
We experimentally demonstrate a quantum key distribution (QKD) protocol using
photon pairs entangled in orbit angular momentum (OAM). In our protocol, Alice
and Bob modulate their OAM states on each entangled pair with spatial light
modulators (SLMs), respectively. Alice uses a fixed phase hologram in her SLM,
while Bob designs different suitable phase holograms and uses them to
represent his -based information in his SLM. With coincidences, Alice can
fully retrieve the key stream sent by Bob without information reconciliation or
privacy amplification. We report the experiment results with N=3 and the sector
states with OAM eigenmodes l=1 and l=-1. Our experiment shows that the
coincidence rates are in relatively distinct value regions for the three
different key elements. Alice could recover fully Bob's keys by the protocol.
Finally, we discuss the security of the protocol both form the light way and
against the general attacks
Analysis of genetic diversity and construction of core collection of local mulberry varieties from Shanxi Province based on ISSR marker
Genetic diversity of 73 local mulberry varieties from Shanxi Province were screened using ISSR markers, with l5 primers combinations selected for their reproducibility and polymorphism. 129 bands were amplified, of which 115 bands showed polymorphism and the ratio of polymorphism bands was 89.15%. Nei’s genetic similarity coefficients ranged from 0.5891 to 0.9457 with an average of 0.7674. The observed number of alleles of each loci, effective number of alleles of each loci, Nei’s gene diversity, Shannon’s information index were 1.8915, 1.4771, 0.2780 and 0.4197, respectively. Clustering results showed that the 73 varieties could be divided into three different groups and nine subgroups. By using stepwise clustering and random methods and the modified heuristic algorithm, 21 core collections were constructed and the ratio of core collection was 28.77%. The result of t-test to the parameters (the number effective of alleles, Nei's genetic diversity index and Shannon's information index) showed that there was not significant difference between the core collection and initial sample with the exception of the number of observed alleles, that is, the core collection could well represent the initial sample.Key words: Mulberry, germplasm resource, genetic diversity, ISSR, cluster analysis, core collection
Physical accessible transformations on a finite number of quantum states
We consider to treat the usual probabilistic cloning, state separation,
unambiguous state discrimination, \emph{etc} in a uniform framework. All these
transformations can be regarded as special examples of generalized completely
positive trace non-increasing maps on a finite number of input states. From the
system-ancilla model we construct the corresponding unitary implementation of
pure pure, pure mixed, mixed pure, and mixed mixed
states transformations in the whole system and obtain the necessary and
sufficient conditions on the existence of the desired maps. We expect our work
will be helpful to explore what we can do on a finite set of input states.Comment: 7 page
Limitations of practical multi-photon decoherence-free states
It is shown in this paper that decoherence-free subspace (DFS) of practical
multi-photon polarization can not avoid the exponential decoherence even in the
same extra-environment if the photons are frequency-anticorrelated. The reason
lies in that the condition of collective decoherence is not satisfied in this
case. As an example, the evolution of biphoton's decoherence-free state is
given. Possible solution for feasible multi-photon's DFS state is also given.Comment: 6 pages, no figur
Scheme for demonstrating Bell theorem in tripartite entanglement between atomic ensembles
We propose an experimentally feasible scheme to demonstrate quantum
nonlocality, using Greenberger-Horne-Zeilinger (GHZ) and entanglement
between atomic ensembles generated by a new developed method based on laser
manipulation and{} single-photon detection.Comment: 10 pages, 4 figure
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