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In situ structures of the segmented genome and RNA polymerase complex inside a dsRNA virus.
Viruses in the Reoviridae, like the triple-shelled human rotavirus and the single-shelled insect cytoplasmic polyhedrosis virus (CPV), all package a genome of segmented double-stranded RNAs (dsRNAs) inside the viral capsid and carry out endogenous messenger RNA synthesis through a transcriptional enzyme complex (TEC). By direct electron-counting cryoelectron microscopy and asymmetric reconstruction, we have determined the organization of the dsRNA genome inside quiescent CPV (q-CPV) and the in situ atomic structures of TEC within CPV in both quiescent and transcribing (t-CPV) states. We show that the ten segmented dsRNAs in CPV are organized with ten TECs in a specific, non-symmetric manner, with each dsRNA segment attached directly to a TEC. The TEC consists of two extensively interacting subunits: an RNA-dependent RNA polymerase (RdRP) and an NTPase VP4. We find that the bracelet domain of RdRP undergoes marked conformational change when q-CPV is converted to t-CPV, leading to formation of the RNA template entry channel and access to the polymerase active site. An amino-terminal helix from each of two subunits of the capsid shell protein (CSP) interacts with VP4 and RdRP. These findings establish the link between sensing of environmental cues by the external proteins and activation of endogenous RNA transcription by the TEC inside the virus
Hydrogen at the rooftop: Compact CPV-hydrogen system to convert sunlight to hydrogen
Despite being highest potential energy source, solar intermittency and low power density make it difficult for solar energy to compete with the conventional power plants. Highly efficient concentrated photovoltaic (CPV) system provides best technology to be paired with the electrolytic hydrogen production, as a sustainable energy source with long term energy storage. However, the conventional gigantic design of CPV system limits its market and application to the open desert fields without any rooftop installation scope, unlike conventional PV. This makes CPV less popular among solar energy customers. This paper discusses the development of compact CPV-Hydrogen system for the rooftop application in the urban region. The in-house built compact CPV system works with hybrid solar tracking of 0.1° accuracy, ensured through proposed double lens collimator based solar tracking sensor. With PEM based electrolyser, the compact CPV-hydrogen system showed 28% CPV efficiency and 18% sunlight to hydrogen (STH) efficiency, for rooftop operation in tropical region of Singapore. For plant designers, the solar to hydrogen production rating of 217 kWhe/kgH2 has been presented with 15% STH daily average efficiency, recorded from the long term field operation of the syste
Estimate of CP Violation for the LBNE Project and $\delta_{CP}
Measurements of CP violation (CPV) and the basic parameter are
the goals of the LBNE Project, which is being planned. Using the expected
energy and baseline parameters for the LBNE Project, CPV and the dependence of
CPV on are estimated, to help in the planning of this project.Comment: 7 pages, 1 figur
Group-theoretic restrictions on generation of CP-violation in multi-Higgs-doublet models
It has been known since decades that imposing a symmetry group G on the
scalar sector of multi-Higgs-doublet models has consequences for CP-violation.
In all examples of two- and three-Higgs-doublet models equipped with
symmetries, one observes the following intriguing property: if G prevents
explicit CP-violation (CPV), at least in the neutral Higgs sector, then it also
prevents spontaneous CPV, and if G allows explicit CPV, then it allows for
spontaneous CPV. One is led to conjecture that this is a general phenomenon. In
this paper, we prove this conjecture for any rephasing symmetry group G and any
number of doublets.Comment: 16 page
EDMs vs. CPV in B_{s,d} mixing in two Higgs doublet models with MFV
We analyze the correlations between electric dipole moments (EDMs) of the
neutron and heavy atoms and CP violation in B_{s,d} mixing in two Higgs doublet
models respecting the Minimal Flavour Violation hypothesis, with flavour-blind
CP-violating (CPV) phases. In particular, we consider the case of flavour-blind
CPV phases from i) the Yukawa interactions and ii) the Higgs potential. We show
that in both cases the upper bounds on the above EDMs do not forbid sizable
non-standard CPV effects in B_s mixing. However, if a large CPV phase in B_s
mixing will be confirmed, this will imply EDMs very close to their present
experimental bounds, within the reach of the next generation of experiments, as
well as BR(B_{s,d}-> mu^+ mu^-) typically largely enhanced over its SM
expectation. The two flavour-blind CPV mechanisms can be distinguished through
the correlation between S_psi K_S and S_psi phi that is strikingly different if
only one of them is relevant. Which of these two CPV mechanisms dominates
depends on the precise values of S_psi phi and S_psi K_S, as well as on the CKM
phase (as determined by tree-level processes). Current data seems to show a
mild preference for a hybrid scenario where both these mechanisms are at work.Comment: 9 pages, 8 figures. V2: minor modifications, few typos corrected, few
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