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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
A US-India Example in Case History Use in Levee Safety — A Multi-Cultural Perception of What It Is, and How Should It Be Applied
The State of Bihar, India experienced substantial flooding in the Ganges Basin as a result of levee (embankment) non performance. As a result of the 2008 failures the Bihar Water Resources Department is examining, as a programmatic model, the US experience in establishing and conducting the United States Army Corps of Engineers (USACE) Levee Safety Program. This case model examination is intended to structure a new program for managing the Bihari embankment infrastructure. Similar to many historical flood control initiatives throughout the world, India’s embankment infrastructure shows the effects of aging and multi-purpose use of the facilities. To examine what practices that could be employed to increase the reliable performance of the embankment system; the World Bank facilitated a detailed case history examination of the USACE Levee Safety Program. The case study included a trial application of elements of the US approach to Indian Levee systems in order to stimulate discussion of what elements could be and should be incorporated into the Indian embankment management system. Elements of the levee safety program examined in this case study include the development of a comprehensive database of features and information on the embankments, a data viewer, areas of maintenance issues and corrective maintenance management activities
MiniSUPERB: Lightweight Benchmark for Self-supervised Speech Models
Self-supervised learning (SSL) is a popular research topic in speech
processing. Successful SSL speech models must generalize well. SUPERB was
proposed to evaluate the ability of SSL speech models across many speech tasks.
However, due to the diversity of tasks, the evaluation process requires huge
computational costs. We present MiniSUPERB, a lightweight benchmark that
efficiently evaluates SSL speech models with comparable results to SUPERB while
greatly reducing the computational cost. We select representative tasks and
sample datasets and extract model representation offline, achieving 0.954 and
0.982 Spearman's rank correlation with SUPERB Paper and SUPERB Challenge,
respectively. In the meanwhile, the computational cost is reduced by 97% in
regard to MACs (number of Multiply-ACcumulate operations) in the tasks we
choose. To the best of our knowledge, this is the first study to examine not
only the computational cost of a model itself but the cost of evaluating it on
a benchmark
A Study of the Water Cherenkov Calorimeter
The novel idea of water Cherenkov calorimeter made of water tanks as the next
generation neutrino detector for nu factories and nu beams is investigated. A
water tank prototype with a dimension of 1*1*13m^3 is constructed, its
performance is studied and compared with a GEANT4 based Monte Carlo simulation.
By using measured parameters of the water tank, including the light collection
efficiency, attenuation length, angular dependent response etc, a detailed
Monte Carlo simulation demonstrates that the detector performance is excellent
for identifying neutrino charged current events while rejecting neutral current
and wrong-flavor backgrounds.Comment: 19 pages, 14 figures, submitted to NI
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