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Copy number variation (CNV) serves as a crucial source of genomic variation and significantly aids in the mining of genomic information in cattle. This study aims to analyze re–sequencing data from Chinese Hainan yellow cattle, to uncover breed CNV information, and to elucidate the resources of population genetic variation. We conducted whole–genome sequencing on 30 Chinese Hainan yellow cattle, thus generating 814.50 Gb of raw data. CNVs were called using CNVnator software, and subsequent filtering with Plink and HandyCNV yielded 197,434 high–quality CNVs and 5852 CNV regions (CNVRs). Notably, the proportion of deleted sequences (81.98%) exceeded that of duplicated sequences (18.02%), with the lengths of CNVs predominantly ranging between 20 and 500 Kb This distribution demonstrated a decrease in CNVR count with increasing fragment length. Furthermore, an analysis of the population genetic structure using CNVR databases from Chinese, Indian, and European commercial cattle breeds revealed differences between Chinese Bos indicus and Indian Bos indicus. Significant differences were also observed between Hainan yellow cattle and European commercial breeds. We conducted gene annotation for both Hainan yellow cattle and European commercial cattle, as well as for Chinese Bos indicus and Indian Bos indicus, identifying 206 genes that are expressed in both Chinese and Indian Bos indicus. These findings may provide valuable references for future research on Bos indicus. Additionally, selection signatures analysis based on Hainan yellow cattle and three European commercial cattle breeds identified putative pathways related to heat tolerance, disease resistance, fat metabolism, environmental adaptation, candidate genes associated with reproduction and the development of sperm and oocytes (CABS1, DLD, FSHR, HSD17B2, KDM2A), environmental adaptation (CNGB3, FAM161A, DIAPH3, EYA4, AAK1, ERBB4, ERC2), oxidative stress anti–inflammatory response (COMMD1, OXR1), disease resistance (CNTN5, HRH4, NAALADL2), and meat quality (EHHADH, RHOD, GFPT1, SULT1B1). This study provides a comprehensive exploration of CNVs at the molecular level in Chinese Hainan yellow cattle, offering theoretical support for future breeding and selection programs aimed at enhancing qualities of this breed. [ABSTRACT FROM AUTHOR]

ABSTRACT Heat- and salt-resistant amphiprotic polyacrylamide microsphere (APMS) was synthesized using inverse microemulsion polymerization method. The microstructure, swellability, filtration, and core flooding performances were tested and characterized. FT-IR spectroscopy indicates that APMS was successfully prepared. Morphological analysis reveals that it is relatively uniform and spherical with an average diameter about 50 nm. Its average diameter increases up to 634 nm after aging at 90°C for 7 days in synthetic brine. After aging for 30 days, the particle size is decreased to 482 nm. But the swelling magnification is still 9.6 times its initial diameter. Compared with the traditional microspheres, APMS exhibits excellent thermal stability, salt resistance, and swelling properties. In addition, the plugging factor is in the range of 0.236 to 0.317, and the number of particles for bridge-plugging is slightly increased from 2 to 4 over aging time. Moreover, the plugging parameters show that APMS can favorably enter and effectively plug the artificial cores with permeability of 0.19 to 0.50 µm2 by deformation, breakthrough and migration, bridging and plugging mechanisms. Furthermore, APMS also shows well its resistance to water flushing and good plugging strength in continuous injection experiment. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43366. [ABSTRACT FROM AUTHOR]

Using artificial cores, six different partially crosslinked polyacrylamide (PCPAM) suspensions were used for sandpacked core flow experiments; the results indicated that the migration of the PCPAM particles through porous media was a process of plugging and flooding at the same time. A theoretical model was proposed and the sensitive parameter, G′, was determined by rheological oscillation measurements with a 200 μm plate gap. In addition, the validity of the proposed theoretical model was verified by the results of the core flow experiments and a fitting equation of ΔP1 with G′ was obtained which can be used for quantifying the steady-state pressure of PCPAM suspensions flowing through porous media in the core flow experiments. [ABSTRACT FROM AUTHOR]

Homopolymerized and copolymerized partly crosslinked polyacrylamide (PCPAM) with N,N dimethylacrylamide (DMAM) were synthesized by free-radical polymerization, and we comparatively studied the changes of apparent viscosity, hydrolysis degree and rheological properties of the partially hydrolyzed polyacrylamide (HPAM), homopolymerized PCPAM (homo-PCPAM) and copolymerized PCPAM (co-PCPAM) after ageing tests in saline solution, with a mineralization of 30,000 mg/L, at 85°C for 3 months. The results showed that, compared with the poor performance of HPAM, the degradation failure rate of homo-PCPAM obviously slowed down, with an apparent viscosity 0.576 Pas, viscosity retention of 57%, hydrolysis degree increasing by an additional 34.4% after aging for 3 months; However, co-PCPAM exhibited better antiaging stability with an apparent viscosity of 1.83 Pas, viscosity retention of 303%, and hydrolysis degree increasing by an additional 29.4% after the ageing test. On this basis, an antiaging mechanism for PCPAM was proposed. [ABSTRACT FROM AUTHOR]

A new type of partially crosslinked polyacrylamide (PCPAM) which displays promising application in enhanced oil recovery (EOR) has been synthesized via aqueous solution polymerization under adiabatic conditions. Based on methods of real-time infrared monitoring, two-dimensional infrared correlation spectroscopy, and dynamic rheology measurement, an unusual complex formation mechanism of the PCPAM with the multifunctional initiator system is clearly disclosed. A process forming branched structures from three functional dimethylaminoethyl methacrylate (DMAEMA) was exhibited, which was supported by high-resolution Fourier transform infrared (FTIR) information. Furthermore, an interesting reaction process, dominated by reaction dynamics, is proposed. By viscosity matching, a great number of coupling terminations will be generated from the branched end chains which will result in the formation of partially crosslinked structures, whereas lots of branched structures were retained under quick gelling conditions. Consequently, the relative number of branched and crosslinked structures in PCPAM was not only mainly determined by the viscosity of the system but also by the content of DMAEMA. [ABSTRACT FROM AUTHOR]