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Electrode erosion caused by dense plasma in constrictive discharge channel is one of the fundamentally detrimental effects existing in pulsed discharge switches. An enhanced plasma expansion in pseudospark discharge assisted by a magnetic switch (MS) is observed from ICCD images in this paper, accompanied by reduced commutation loss, and the mechanisms are revealed by experiments and simulations. The characteristics of the discharge waveforms and channel images of the pseudospark discharge with and without a series-connected MS are compared, and the influence of the number of magnetic cores is studied. As the loop current increases, the discharge channel expands radically and reaches the maximum as the current rising rate reaches the maximum. As the number of magnetic cores increases from 0 to 8, the maximum diameter of the discharge channel increases from 16 mm to about 38 mm, and the commutation loss is reduced from 30 mJ to 11 mJ. The electrode erosion rate of the case with a MS is lower than that without a MS. A particle in cell/Monte Carlo collision model coupling to nonlinear external circuit elements is established. The simulation results fit well with the experiment phenomena, including the discharge waveforms and the profiles of the discharge channel. The distribution of ions shows more diffused features than that of electrons, while the distribution of electrons is more similar to the discharge channel observed in experiments. The enhanced plasma expansion is mainly caused by the higher radial acceleration component of the charged particles during the magnetically delayed time. [ABSTRACT FROM AUTHOR]

With colorimetric characterization, digital cameras can be used as image-based tristimulus colorimeters for color communication. In order to overcome the restriction of fixed capture settings adopted in the conventional colorimetric characterization procedures, a novel method was proposed considering capture settings. The method calculating colorimetric value of the measured image contains five main steps, including conversion from RGB values to equivalent ones of training settings through factors based on imaging system model so as to build the bridge between different settings, scaling factors involved in preparation steps for transformation mapping to avoid errors resulted from nonlinearity of polynomial mapping for different ranges of illumination levels. The experiment results indicate that the prediction error of the proposed method, which was measured by CIELAB color difference formula, reaches less than 2 CIELAB units under different illumination levels and different correlated color temperatures. This prediction accuracy for different capture settings remains the same level as the conventional method for particular lighting condition. [ABSTRACT FROM AUTHOR]

Background: Bovine papilloma is a neoplastic disease caused by bovine papillomaviruses (BPVs), which were recently divided into 5 genera and at least 24 genotypes., Objectives: The complete genome sequence of BPV type 15 (BPV Aks-02), a novel putative BPV type from skin samples from infected cows in Southern Xinjiang China, was determined by collecting warty lesions, followed by DNA extraction and amplicon sequencing., Methods: DNA was analyzed initially by polymerase chain reaction (PCR) using the degenerate primers FAP59 and FAP64. The complete genome sequences of the BPV Aks-02 were amplified by PCR using the amplification primers and sequencing primers. Sequence analysis and phylogenetic analysis were performed using bio-informatic software., Results: The nucleotide sequence of the L1 open reading frame (ORF) of BPV Aks-02 was 75% identity to the L1 ORF of BPV-9 reference strain from GenBank. The complete genome consisted of 7,189 base pairs (G + C content of 42.50%) that encoded 5 early (E8, E7, E1, E2, and E4) and 2 late (L1 and L2) genes. The E7 protein contained a consensus CX₂CX 29 CX₂C zinc-binding domain and a LxCxE motif. Among the different members of this group, the percentages of the complete genome and ORFs (including 5 early and 2 late ORFs) sequence identity of BPV Aks-02 were closer to the genus Xipapillomavirus 1 of the Xipapillomavirus genus. Phylogenetic analysis and sequence similarities based on the L1 ORF of BPV Aks-02 revealed the same cluster., Conclusions: The results suggest that BPV type (BPV Aks-02) clustered with members of the Xipapillomavirus genus as BPV 15 and were closely related to Xipapillomavirus 1., Competing Interests: The authors declare no conflicts of interest., (© 2020 The Korean Society of Veterinary Science.)