MOLECULAR PHYLOGENETIC ANALYSIS OF MONASCUS FUNGI BASED ON INTERNAL TRANSCRIBED SPACER REGION

A molecular analysis of internal transcribed spacer region has been carried out to reveal the relationship among 16 strains of Monascus spp. A primer set comprised primer ITS1 and ITS4 was used to amplify this region in which they were cloned and scqucnccd. We also compared the sequence result with M. purpureus AF458473, M.ruber AF458470, M. kaoliang AF451859, M. araneous AF458471 and M. pilosus AF451856 and one outgroup species Thermoascus crustaceus U18353. The result showed that 16 Monascus spp. were divided into two large clades while M. ruber AF458470 was basically separated from all those Monascus. One of the two large clades included the seven M. purpureus strains, M. purpureus AF458473, M. araneosus AF458471 and M. kaoliang AF451859. Another large cladc included the six Monascus sp. strains which typically have whitish colonies, the three M. ruber strains and M.pilosus AF451856. However, even outstanding morphological differences possessed by several white Monascus  and one whitish M. purpureus  strain, all Monascus  strains were suggested to be very closely related with similarity >99% almost 100%. Although this ITS analysis could not discriminate cultural and morphological differentiation of Monascus strains studied, yet there is still little genetic variation within these strains. Key words : Molecular genetics/Monascus spp./fung

Molecular Phylogenetic Analysis of Monascus Fungi Based on Internal Transcribed Spacer Region

A molecular analysis of internal transcribed spacer region has been carried out to reveal the relationship among 16 strains of Monascus spp. A primer set comprised primer ITS1 and ITS4 was used to amplify this region in which they were cloned and scqucnccd. We also compared the sequence result with M. purpureus AF458473, M.ruber AF458470, M. kaoliang AF451859, M. araneous AF458471 and M. pilosus AF451856 and one outgroup species Thermoascus crustaceus U18353. The result showed that 16 Monascus spp. were divided into two large clades while M. ruber AF458470 was basically separated from all those Monascus. One of the two large clades included the seven M. purpureus strains, M. purpureus AF458473, M. araneosus AF458471 and M. kaoliang AF451859. Another large cladc included the six Monascus sp. strains which typically have whitish colonies, the three M. ruber strains and M.pilosus AF451856. However, even outstanding morphological differences possessed by several white Monascus and one whitish M. purpureus strain, all Monascus strains were suggested to be very closely related with similarity >99% almost 100%. Although this ITS analysis could not discriminate cultural and morphological differentiation of Monascus strains studied, yet there is still little genetic variation within these strains

A PET Study of Memory for Future Plan

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An addressable quantum dot qubit with fault-tolerant control fidelity

Exciting progress towards spin-based quantum computing has recently been made with qubits realized using nitrogen-vacancy (N-V) centers in diamond and phosphorus atoms in silicon, including the demonstration of long coherence times made possible by the presence of spin-free isotopes of carbon and silicon. However, despite promising single-atom nanotechnologies, there remain substantial challenges in coupling such qubits and addressing them individually. Conversely, lithographically defined quantum dots have an exchange coupling that can be precisely engineered, but strong coupling to noise has severely limited their dephasing times and control fidelities. Here we combine the best aspects of both spin qubit schemes and demonstrate a gate-addressable quantum dot qubit in isotopically engineered silicon with a control fidelity of 99.6%, obtained via Clifford based randomized benchmarking and consistent with that required for fault-tolerant quantum computing. This qubit has orders of magnitude improved coherence times compared with other quantum dot qubits, with T_2* = 120 mus and T_2 = 28 ms. By gate-voltage tuning of the electron g*-factor, we can Stark shift the electron spin resonance (ESR) frequency by more than 3000 times the 2.4 kHz ESR linewidth, providing a direct path to large-scale arrays of addressable high-fidelity qubits that are compatible with existing manufacturing technologies

Effects of low-temperature capping on the optical properties of GaAs/AlGaAs quantum wells

We study the effects of low-temperature capping (200-450°C) on the optical properties of GaAs/AlGaAs quantum wells. Photoluminescence measurements clearly show the formation of abundant nonradiative recombination centers in an AlGaAs capping layer grown at 200°C, while there is a slight degradation of the optical quality in AlGaAs capping layers grown at temperatures above 350°C compared to that of a high-temperature capping layer. In addition, the optical quality can be restored by post-growth annealing without any structural change, except for the 200°C-capped sample