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Liquid-phase plasma is widely used in industry, so it is important to study its characteristics. In this paper, an experimental system utilizing a cylindrical pressure tank with adjustable hydrostatic pressure for studying liquid-phase pulsed discharge plasma is designed, and the components and experimental principles of the system are introduced in detail. Based on this experimental system, the influence of hydrostatic pressure on the characteristics of liquid-phase plasma was investigated under varying voltage levels and electrode spacings. The results demonstrate that the experimental system can effectively generate and observe liquid-phase plasma. As hydrostatic pressure increases, the pre-breakdown delay at 15 kV and a 2 mm electrode gap increases from 25.6 μs at 0.1 MPa to 447.2μs at 0.5 MPa, while the duration of the main discharge stage decreases from 224.4 to 210.4μs. At 13 kV with a 2 mm electrode gap, the emission spectrum intensity and the electron density of the discharge plasma decrease with increasing hydrostatic pressure. The electron temperature in the plasma channel ranges from 11,000 K to 16,500 K. In addition, the discharge process phenomena were analyzed using typical high-speed camera images, highlighting the characteristics of the discharge plasma at each stage. Finally, the shortcomings and improvement of the experimental system are analyzed. [ABSTRACT FROM AUTHOR]

Streamer discharge is a very complex multi-scale and multi-physics coupling process, and there is no accurate model that can describe its development. In this paper, a two-dimensional axisymmetric fluid model is established in COMSOL to simulate and study the effects of the applied voltage amplitude, the discharge gap distance, the rising edge of pulse voltage, and hydrostatic pressure on the development of the positive streamer discharge at a needle-plate electrode in water under a nanosecond pulse voltage. The results show that increasing the voltage amplitude, decreasing the pulse rise time, and narrowing the discharge gap all increase the electric field strength of the streamer, thereby affecting the electron density of the plasma channel, among which changing the discharge gap has the greatest effect on the electron density. And under the gap of 3 mm, the peak electron density can reach 3.76 × 1023 m−3; if the discharge gap is narrowed to 1 mm, the peak electron density is reduced to 1.20 × 1023 m−3. In addition, hydrostatic pressure and water molecule spacing are closely linked. Increasing the hydrostatic pressure decreases the electric field strength and the peak electron density in the plasma channel, and its effect on the peak electron density saturates with increasing hydrostatic pressure. [ABSTRACT FROM AUTHOR]

Copy number variation (CNV) is an important member of genetic structural variation that exists widely in animal genomes and is between 50 bp and several Mb in length and widely used in research's of animal genetics and breeding. ZNF679 is an important transcription factor, which has been found association with diseases in the human genome many times. This gene has also been found to be associated with cattle growth traits in previous re-sequencing studies. We tested the CNVs of the ZNF679 gene in 809 individuals from 7 Chinese cattle breeds and tested the association between the CNVs and growth traits in 552 individuals from 5 breeds. The results demonstrated the correlation the correlation between the CNVs of the ZNF679 gene and some Chinese cattle (QC cattle and XN cattle) growth traits. To sum up, this study indicated that ZNF679-CNVs can be used as a candidate gene for molecular genetic marker-assisted selection breeding for cattle growth traits to contribute to the development of genetic improvement of Chinese cattle. [ABSTRACT FROM AUTHOR]

Recently, Coiled-coil serine-rich protein 1 (CCSER1) gene is reported to be related to economic traits in livestock, and become a hotspot. In our study, we detected CCSER1 gene CNV in 693 goats from six breeds (GZB, GZW, AN, BH, HG, TH) by quantitative real-time PCR (qPCR) and the association analysis between the types of CNV and growth traits. Then, CCSER1 gene expression pattern was discovered in seven tissues from NB goats. Our results showed that the CCSER1 gene copy numbers were distributed differently in the aforementioned six breeds. The type of CCSER1 gene CNV was significantly associated with body weight and heart girth traits in GZW goat, in which individuals with deletion type were dominant in body weight trait (P < 0.05), while the normal type individuals were more advantageous in heart girth trait (P < 0.01); and there was a significant association with heart girth in TH goat (P < 0.05), which normal type was the dominant one. The expression profile revealed that CCSER1 gene has the highest level in the lung, followed by the small intestine and heart. In conclusion, our result is dedicated to an in-depth study of the novel CCSER1 gene CNV site and to provide essential information for Chinese goats molecular selective breeding in the future. [ABSTRACT FROM AUTHOR]

Copy number variant (CNV), a common genetic polymorphism, is closely related to the phenotypic variation traits of organisms. Vesicle-associated membrane protein 7 gene (VAMP7) codes a protein, which is a member of the SNARE proteins family and plays an important role in the process of intracellular vesicle transport. In this study, a total of four cattle breeds (Yunling cattle, Xianan cattle, Pinan cattle, Jiaxian red cattle) were used to investigate the copy numbers, and we found an association relationship between CNV of VAMP7 gene and growth traits of cattle by SPSS 20.0 software. The results showed that the CNV type of VAMP7 gene in four cattle breeds had the same distribution, Duplication type occupies a dominant position among the four varieties. In Yunling cattle, the Duplication type of VAMP7 is significantly related to the height at the hip cross (p < 0.05), Individuals with Duplication type commonly have less performance on growth and development, which indicates that the Duplication type of the VAMP7 gene may have a negative effect on cattle growth. Individuals with the other two CNV types may become the breeding direction of the VAMP7 gene. This study provided a new perspective and basic material for the molecular genetics of the CNV of the VAMP7 gene, and also promoted the breeding progress of Chinese local cattle. [ABSTRACT FROM AUTHOR]

The aim of this study was to detect the novel copy number variation (CNV) locus of NCAM2 gene in Chinese Holstein, and to analyze the effect of the novel CNV locus in NCAM2 gene on milk composition traits. The novel CNV locus of NCAM2 gene in 310 Chinese Holstein was detected by real-time quantitative fluorescent PCR (qPCR) and association analysis was performed between the novel CNV locus in NCAM2 gene and milk composition traits in Chinese Holstein. There are three CNV types of NCAM2 gene in Chinese Holstein: gain (increased copy number), median (normal copy number) and loss (deleted copy number). Statistical analysis revealed that there was a significant association between CNV types and milk fat rate (p < 0.05). Moreover, we also discovered that the milk production and milk protein rate of gain type is higher than that of loss type, but that of mediate type is lower than that of loss type. However, in terms of somatic cell score, loss type is higher than that of gain type, but that of mediate type is lower than that of gain type. These observations suggested that gain type can be used as a candidate molecular genetic marker of milk fat rate. The CNVs of the NCAM2 gene were detected and validated in Chinese Holstein. The type of CNV was successfully implemented using qPCR. The statistical analysis indicated that the CNV of the NCAM2 gene are significantly associated with milk fat rate. [ABSTRACT FROM AUTHOR]

Copy number variations (CNVs) were similar to single nucleotide polymorphisms (SNPs) and insertion-deletion (InDel), regarded as genetic variations in many species. CNV is defined as the variable change of DNA segment length compared with the reference genome, including gains or losses from 50 bp to several mega bases. The functions of USP16 gene are diverse, such as regulating the cell cycle, DNA damage, histone H2A deubiquitination or mitotic nuclear division. To analyze the relationship between CNV of USP16 gene and milk traits in Chinese Holstein, we used qPCR to detect the individuals of Chinese Holstein (n = 180). The results showed that the effect of USP16 gene CNV on daily milk yield and fat percentage had significant difference (p < 0.05). The gain was the advantage type in daily milk yield and the loss was the advantage type in fat percentage. Therefore, CNV of USP16 gene is an important factor of milk traits in Chinese Holstein. Meanwhile, it may be used as a molecular marker for assisted selection of milk traits in Chinese Holstein, which provides a theoretical basis for the genetic improvement of cow breeds in China. [ABSTRACT FROM AUTHOR]