6,431 research outputs found
transitions in the light cone sum rules with the chiral current
semi-leptonic decays to the light scalar meson, , are investigated in the QCD
light-cone sum rules (LCSR) with chiral current correlator. Having little
knowledge of ingredients of the scalar mesons, we confine ourself to the two
quark picture for them and work with the two possible Scenarios. The resulting
sum rules for the form factors receive no contributions from the twist-3
distribution amplitudes (DA's), in comparison with the calculation of the
conventional LCSR approach where the twist-3 parts play usually an important
role. We specify the range of the squared momentum transfer , in which the
operator product expansion (OPE) for the correlators remains valid
approximately. It is found that the form factors satisfy a relation consistent
with the prediction of soft collinear effective theory (SCET). In the effective
range we investigate behaviors of the form factors and differential decay
widthes and compare our calculations with the observations from other
approaches. The present findings can be beneficial to experimentally identify
physical properties of the scalar mesons.Comment: 22 pages,16 figure
The role of F1 ATP synthase beta subunit in WSSV infection in the shrimp, Litopenaeus vannamei
<p>Abstract</p> <p>Background</p> <p>Knowledge of the virus-host cell interaction could inform us of the molecular pathways exploited by the virus. Studies on viral attachment proteins (VAPs) and candidate receptor proteins involved in WSSV infection, allow a better understanding of how these proteins interact in the viral life cycle. In this study, our aim was to find some host cellular membrane proteins that could bind with white spot syndrome virus (WSSV).</p> <p>Results</p> <p>Two proteins were evident by using a virus overlay protein binding assay (VOPBA) with WSSV. A protein with molecular weight 53 kDa, named BP53, was analyzed in this study, which was homologous with the F<sub>1</sub>-ATP synthase beta subunit by mass spectrometry analysis. Rapid amplification of cDNA ends (RACE) PCR was performed to identify the full-length cDNA of the <it>bp53 </it>gene. The resulting full-length gene consisted of 1836 bp, encoding 525 amino acids with a calculated molecular mass of 55.98 kDa. The deduced amino acid sequence contained three conserved domains of the F<sub>1</sub>-ATP synthase beta subunit. BP53 was therefore designated the F<sub>1</sub>-ATP synthase beta subunit of <it>L. vannamei</it>. The binding of WSSV to BP53 were also confirmed by competitive ELISA binding assay and co-immunoprecipitation on magnetic beads. To investigate the function of BP53 in WSSV infection, it was mixed with WSSV before the mixture was injected intramuscularly into shrimp. The resulting mortality curves showed that recombinant (r) BP53 could attenuate WSSV infection.</p> <p>Conclusions</p> <p>The results revealed that BP53 is involved in WSSV infection. Here is the first time showed the role of shrimp F<sub>1</sub>-ATP synthase beta subunit in WSSV infection.</p
Single and Two-Phase Heat Transfer Enhancement Using Longitudinal Vortex Generator in Narrow Rectangular Channel
Plant Age Effect on Mechanical Properties of Moso Bamboo (Phyllostachys Heterocycla Var. Pubescens) Single Fibers
Bamboo fiber has greater mechanical strength than certain other natural fibers and could therefore be a candidate for production of fiber-reinforced composites. Single fibers were isolated from Moso bamboo samples taken from plants between 0.5 and 8.5 yr old. Mechanical properties of single fibers (tensile strength, modulus of elasticity (MOE), and other mechanical related properties such as the microfibril angle and fiber cross-sectional area) were studied. There was no significant variation with age in average MOE and fracture strain of the bamboo fibers. Results indicate that the thickening growth of cell walls in bamboo fibers near the outer surface of bamboo is almost complete by 0.5 yr. Therefore, fibers from 0.5 to 8.5 yr old plants may be used for making fiber-reinforced composites
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