149 research outputs found
Identification, sequence analysis, and phylogeny of the immediate early gene 1 of the trichoplusia ni single nucleocapsid polyhedrosis virus
Substantial research has been conducted on the immediate early 1 (ie-1) genes from the prototype baculovirus
Autographa californica multicapsid nuclear polyhedrosis virus (AcMNPV) and the Orgyia pseudotsugata
multicapsid nuclear polyhedrosis virus (OpMNPV). In both cases ie-1 gene products have been implicated in transcriptional
activation and repression. In this study an ie-1 homolog was identified from Trichoplusia ni single
nucleocapsid polyhedrosis virus (TniSNPV). Nucleotide sequence analysis indicated that the TniSNPV ie-1 gene
consists of a 2217 nucleotide open reading frame (ORF), encoding a protein with a molecular mass of 84.464 kDa.
This represents the largest baculovirus ie-1 gene characterised to date. Of the seven ie-1 homologs identified to date,
the TniSNPV ie-1 shared most sequence similarity with the ie-1 gene of Spodoptera exigua MNPV (SeMNPV)
(41%). At the nucleotide level, expected TATA and CAGT motifs were found to precede each ie-1 ORF. At the
protein level, it was confirmed that the N-termini are poorly conserved, but share the characteristic of having a
high proportion of acidic amino acids. In addition it was found that N-terminal regions significantly matched the
SET domain in the Swiss-Prot prosite database. The C-terminal regions of the deduced IE-1 sequences were found
to be substantially more conserved than the N-termini. Several conserved motifs were identified in the C-terminal
sequences. A phylogenetic tree of nine baculovirus IE-1 proteins was constructed using maximum parsimony analysis.
The phylogenetic estimation of the ie-1 genes shows that TniSNPV is a member of the previously described
lepidopteran NPV group II and it is most closely related to SeMNPV.Web of Scienc
Comparison of beam theories for characterisation of a NREL wind turbine blade flap-wise vibration
Offshore wind turbine blades significantly differ from their onshore counterparts. With the increasing sizes, the hostile weather operational conditions, and the need to protect them against damage and breakdown, structural dynamics analysis is an essential and popular approach. An accurate and computationally simple model is desirable in the application of online structural health monitoring. For example using a digital twin of such structure. Free vibration investigation is a fundamental step for the analysis of structural dynamics. When a rotating blade deflects either in the plane of rotation or perpendicular to it, the centrifugal force on each blade exerts inertia force along the blade span, which has the effect of stiffening the blade and, as a result increasing the natural frequencies compared with the stationary ones. However, the influence of different blade parameters on the flap-wise vibrations is not very well understood. In this paper, the blade of horizontal axis wind turbines (HAWT) is modelled using different beam theories to pursue the effect of adding the different parameters on the dynamic modal characteristics. The examined models have been used to determine the natural frequencies and mode shapes of the National Renewable Energy Laboratory (NREL) 5-MW wind turbine. Results demonstrate that increasing angular velocity has a significant impact on the natural frequencies and mode shapes. The rotary inertia is found to impact the free vibration responses of the studied blades. Moreover, increasing hub radius, pre-cone and pitch angles are found to have less influence on the natural frequencies. Compared to the other investigated methods, Bernoulli’s based algorithms are found to produce less accurate results
The genetic organisation of a 2,966 basepair DNA fragment of a Single Capsid Nucleopolyhedrovirus isolated from Trichoplusia ni
In order to investiagte the genomic organization of the Trichoplusia ni Single Capsid Nucleoplyhedrovirus (TnSNPV) , a 2,966 base pairs (bp) genomic fragment was sequenced. The fragment was found to contain five open reading frames (ORF's) homologous to baculovirus genes, including p26, fibrillin (p10), AcMNPV ORF-29, late expression facor 6 (lef 6) and the C-terminal portion of p74, on either stand of DNA. Predicted amini acid sequences for the ORFs were compared and identity values of between 12% and 54% were observed. Clustering and arrangement of the TnSNPV genes were similar to the clustering reported for SeMNPV, confirming TnSNPV was a Group II NPV.IS
Joint Generator-Ranker Learning for Natural Language Generation
Generate-then-rank is a widely used mechanism for text generation, where a
generator produces multiple text candidates and a ranker chooses the best one
among the text candidates. However, existing methods usually train the
generator and the ranker individually, neglecting the mutual feedback that
could further enhance the generation quality. To tackle this limitation, we
propose JGR, a novel joint training algorithm that integrates the generator and
the ranker in a single framework. JGR optimizes the generator with a hybrid
objective that combines data likelihood and ranker reward, and trains the
ranker with a contrastive loss that compares the generator outputs. By
iteratively updating the generator and the ranker, JGR can effectively
harmonize their learning and enhance their quality jointly. We evaluate JGR on
various text generation tasks and demonstrate that it surpasses existing
methods on four public datasets across three common generation scenarios. Our
code and models are publicly available at
https://github.com/microsoft/ProphetNet/tree/master/JGR
- …