456 research outputs found
Integrated photonic qubit quantum computing on a superconducting chip
We study a quantum computing system using microwave photons in transmission
line resonators on a superconducting chip as qubits. We show that all control
necessary for quantum computing can be implemented by coupling to Josephson
devices on the same chip, and take advantage of their strong inherent
nonlinearities to realize qubit interactions. We analyze the gate error rate to
demonstrate that our scheme is realistic even for Josephson devices with
limited decoherence times. A conceptually innovative solution based on existing
technologies, our scheme provides an integrated and scalable approach to the
next key milestone for photonic qubit quantum computing.Comment: 5 pages, 3 figure
Ca2+ signaling in HEK-293 and skeletal muscle cells expressing recombinant ryanodine receptors harboring malignant hyperthermia and central core disease mutations.
Malignant hyperthermia (MH) and central core disease (CCD) are caused by mutations in the RYR1 gene encoding the skeletal muscle isoform of the ryanodine receptor (RyR1), a homotetrameric Ca(2+) release channel. Rabbit RyR1 mutant cDNAs carrying mutations corresponding to those in human RyR1 that cause MH and CCD were expressed in HEK-293 cells, which do not have endogenous RyR, and in primary cultures of rat skeletal muscle, which express rat RyR1. Analysis of intracellular Ca(2+) pools was performed using aequorin probes targeted to the lumen of the endo/sarcoplasmic reticulum (ER/SR), to the mitochondrial matrix, or to the cytosol. Mutations associated with MH caused alterations in intracellular Ca(2+) homeostasis different from those associated with CCD. Measurements of luminal ER/SR Ca(2+) revealed that the mutations generated leaky channels in all cases, but the leak was particularly pronounced in CCD mutants. Cytosolic and mitochondrial Ca(2+) transients induced by caffeine stimulation were drastically augmented in the MH mutant, slightly reduced in one CCD mutant (Y523S) and completely abolished in another (I4898T). The results suggest that local Ca(2+) derangements of different degrees account for the specific cellular phenotypes of the two disorders
Identification of MicroRNAs in Two Species of Tomato, \u3ci\u3eSolanum lycopersicum\u3c/i\u3e and \u3ci\u3eSolanum habrochaites\u3c/i\u3e, by Deep Sequencing
MicroRNAs (miRNAs) are ~21 nucleotide (nt), endogenous RNAs that regulate gene expression in plants. Increasing evidence suggests that miRNAs play an important role in species-specific development in plants. However, the detailed miRNA profile divergence has not been performed among tomato species. In this study, the small RNA (sRNA) profiles of Solanum lycopersicum cultivar 9706 and Solanum habrochaites species PI 134417 were obtained by deep sequencing. Sixty-three known miRNA families were identified from these two species, of which 39 were common. Further miRNA profile comparison showed that 24 known non-conserved miRNA families were species-specific between these two tomato species. In addition, six conserved miRNA families displayed an apparent divergent expression pattern between the two tomato species. Our results suggested that species-specific, non-conserved miRNAs and divergent expression of conserved miRNAs might contribute to developmental changes and phenotypic variation between the two tomato species. Twenty new miRNAs were also identified in S. lycopersicum. This research significantly increases the number of known miRNA families in tomato and provides the first set of small RNAs in S. habrochaites. It also suggests that miRNAs have an important role in species-specific plant developmental regulation
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