205 research outputs found
Complete temporal mode characterization of non-Gaussian states by dual homodyne measurement
Optical quantum states defined in temporal modes, especially non-Gaussian
states like photon-number states, play an important role in quantum computing
schemes. In general, the temporal-mode structures of these states are
characterized by one or more complex functions called temporal-mode functions
(TMFs). Although we can calculate TMF theoretically in some cases, experimental
estimation of TMF is more advantageous to utilize the states with high purity.
In this paper, we propose a method to estimate complex TMFs. This method can be
applied not only to arbitrary single-temporal-mode non-Gaussian states but also
to two-temporal-mode states containing two photons. This method is implemented
by continuous-wave (CW) dual homodyne measurement and doesn't need prior
information of the target states nor state reconstruction procedure. We
demonstrate this method by analyzing several experimentally created
non-Gaussian states
Schr\"odinger's cat in an optical sideband
We propose a method to subtract a photon from a double sideband mode of
continuous-wave light. The central idea is to use phase modulation as a
frequency sideband beamsplitter in the heralding photon subtraction scheme,
where a small portion of the sideband mode is downconverted to the carrier
frequency to provide a trigger photon. An optical Schr\"odinger's cat state is
created by applying the propesed method to a squeezed state at 500MHz sideband,
which is generated by an optical parametric oscillator. The Wigner function of
the cat state reconstructed from a direct homodyne measurement of the 500MHz
sideband modes shows the negativity of without any
loss corrections.Comment: 11 pages, 9 figure
Quantum mode filtering of non-Gaussian states for teleportation-based quantum information processing
We propose and demonstrate an effective mode-filtering technique of
non-Gaussian states generated by photon-subtraction. More robust non-Gaussian
states have been obtained by removing noisy low frequencies from the original
mode spectrum. We show that non-Gaussian states preserve their non-classicality
after quantum teleportation to a higher degree, when they have been
mode-filtered. This is indicated by a stronger negativity of
the Wigner function at the origin, compared to for states
that have not been mode-filtered. This technique can be straightforwardly
applied to various kinds of photon-subtraction protocols, and can be a key
ingredient in a variety of applications of non-Gaussian states, especially
teleportation-based protocols towards universal quantum information processing
Measurement of intracellular pH by flow cytometry using pH sensitive fluorescence dye, and influence of hyperthermia and amiloride derivatives on the intracellular pH
エールリッヒ腹水癌細胞とそのアドリアマイシン耐性細胞において蛍光pH指示薬2'、7'-bis-(2-carboxyethyl) carboxyfluorescein] (BCECF) の蛍光量をフローサイトメトリーで測定することによって細胞内pHの検量曲線を作成することができた。このことより、これらの細胞においてBCECFの蛍光量で細胞内pHの変化を簡易に比較できることを示唆した。さらに、温熱、Na(+)/H(+) exchanger の阻害例であるアミロライド[3,5-diamino-6-chloro-N-(diaminomethylene) pyrazinecarboxamide]、およびアミロライド誘導隊MH-12-43[N-amidino-3-amino-6-chloro-5-(N-ethyliso-propylamino) pyrazinecarboxyamide] の細胞内pHへの影響をエールリッヒ腹水癌細胞で観察した。37℃では、0.5mMアミロライド、0.05mM MH-12-43により細胞内pHは減少し、42℃処理によりさらに減少した。42℃において、0.05mM MH-12-43による細胞内pHの減少は、0.5mMアミロライドによる減少より大きかった。We examined relationship between intensity of intracellular fluorescence of [2', 7'-bis-(2'-carboxyethyl) carboxyfluorescein] (BCECF) and intracellular pH in Ehrlich ascites tumor cells and their adriamycin-resistant strain, and found a good correlation between them at both strains. This suggests that changes in the intracellular pH on these strains may be obtained through measurement of intracellular fluorescence of BCECF by flow cytometry. Further, we examined influence of hyperthermia, 3, 5-diamino-6-chloro-N-(diaminomethylene)pyrazinecarboxamide (amiloride), an inhibitor of Na(+)/H(+) exchanger, and its derivative; N-amidino-3-amino-6-chloro-5-(N-ethylisopropylamino) pyrazinecarboxyamide (MH-12-43) on the intracellular pH in Ehrlich ascites tumor cells. The treatment of 0.5mM amiloride or 0.05mM MH-12-43 reduced intracellular pH at 37℃, while the more reduction was observed by the treatment at 42℃. The reduction of intracellular pH by 0.05mM MH-12-43 was more substantial than that of 0.5mM amiloride at 42℃
H-DBAS: Alternative splicing database of completely sequenced and manually annotated full-length cDNAs based on H-Invitational
The Human-transcriptome DataBase for Alternative Splicing (H-DBAS) is a specialized database of alternatively spliced human transcripts. In this database, each of the alternative splicing (AS) variants corresponds to a completely sequenced and carefully annotated human full-length cDNA, one of those collected for the H-Invitational human-transcriptome annotation meeting. H-DBAS contains 38 664 representative alternative splicing variants (RASVs) in 11 744 loci, in total. The data is retrievable by various features of AS, which were annotated according to manual annotations, such as by patterns of ASs, consequently invoked alternations in the encoded amino acids and affected protein motifs, GO terms, predicted subcellular localization signals and transmembrane domains. The database also records recently identified very complex patterns of AS, in which two distinct genes seemed to be bridged, nested or degenerated (multiple CDS): in all three cases, completely unrelated proteins are encoded by a single locus. By using AS Viewer, each AS event can be analyzed in the context of full-length cDNAs, enabling the user's empirical understanding of the relation between AS event and the consequent alternations in the encoded amino acid sequences together with various kinds of affected protein motifs. H-DBAS is accessible at
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