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Simple Summary: Interspecies somatic cell nuclear transfer (iSCNT) is valuable for preserving endangered animals. The objective of this study was to investigate the morphokinetic parameters of fishing cat–domestic cat (iSCNT) embryos from one cell to blastocyst stages, and in particular, the cleavage patterns of the first division in iSCNT and IVF embryos, as these play a central role in euploidy. A time-lapse imaging system is potentially a powerful tool for selecting early embryos with developmental potential for transfer, and hence, for improving feline iSCNT efficiency. A time-lapse live embryo monitoring system provides a powerful approach to recording dynamic developmental events of cultured embryos in detail. By obtaining continuous short-interval images, blastocyst formation can be predicted and embryos can be selected. The objective of this study was to investigate the morphokinetic parameters of fishing cat–domestic cat interspecies somatic cell nuclear transfer (iSCNT) embryos from one-cell to blastocyst stages, and in particular, the cleavage patterns of the first division in iSCNT and IVF embryos, as these play a central role in euploidy. Domestic cat in vitro fertilization (IVF) embryos were set up as controls. The results show that morula and blastocyst development rates were significantly lower in the iSCNT embryos compared to their IVF counterparts. All earlier time points of embryonic development before the onset of blastulation in the iSCNT embryos were significantly delayed when compared with their IVF counterparts. In iSCNT, normal embryos (defined as those that developed to the blastocyst stage) took a longer time to reach the morula stage, and these morulas were more likely to undergo compaction, compared to their arrested embryo counterparts. Direct cleavage in the first division is a morphological aberration, and was seen with greater prevalence in iSCNT embryos than control IVF embryos; these aberrant embryos displayed a significantly lower blastocyst development rate than embryos that had undergone normal cleavage. In conclusion, the morphokinetic parameters of fishing cat–domestic cat iSCNT embryos at early stages could be used to predict their potential for development to the blastocyst stage. A time-lapse imaging system is potentially a powerful tool for selecting early embryos with developmental potential for transfer, and hence, for improving feline iSCNT efficiency. [ABSTRACT FROM AUTHOR]

A cubic flatness pattern expressed by Legendre orthogonal polynomial was introduced to build a new flatness pattern recognition model,in which least squares regression was used. Using the new model,flatness pattern recognitions of 2180 mm CVC ultra-wide cold rolling mill and 1550 mm UCM common wide tandem cold rolling mill were carried out. The results show that the main flatness error of the strip produced by the ultra-wide mill is "OS cubic waves" considering the cubic flatness pattern,and "quarter waves" without the cubic pattern; the main flatness error of the strip produced by the common wide mill is "central waves" whether considering the cubic flatness pattern or not,therefore the necessity of introducing cubic flatness pattern for the new recognition model is verified. Finally,potential application of the new model in the asymmetric flatness control of ultra-wide tandem cold rolling mill is discussed.

The regression method was applied to test the two groups of samples mainly composed of mineral oil and vegetable oil. The moisturizing properties of the products were verified by applying the samples for 7 days and 14 days, as well as after stopping the products for 4 days, 7 days and 14 days. It was found that the water content of the stratum corneum was significantly increased and the transepidermal water loss of the skin was significantly reduced after 7 days and 14 days. After 7 days of stopping the samples, the water content of the stratum corneum still maintained a significant increase on the basis of the end of the washout period, and it still had a moisturizing effect. After 14 days of stopping the samples, the transepidermal water loss of the skin was significantly reduced on the basis of the end of the washout period, and it still had a good effect of locking skin water. Among them, the average change rate of transepidermal water loss of vegetable oil samples was lower than that of the mineral oil group, indicating that vegetable oil can better repair skin barrier, and providing reference for the subsequent development of similar products. [ABSTRACT FROM AUTHOR]

In order to reveal the mechanical essence of the detecting principle of SI-FLAT flatness measurement systems, the mathematical model of the relationship between amplitude and residual stress was established, based on the theory of fluid-structure interaction vibration of thin plates. The terms of inertia and fluid pressure were introduced to the equilibrium equation in incompatible Föppl-von Kármán equations. The time variables were separated out from the velocity function of fluid, pressure function of fluid, deflection function of thin plates and stress potential function of thin plates with consideration of periodic aerodynamic load. Therefore, the partial differential equations aiming at steady state of SI-FLAT flatness measurement systems was obtained. Solving the equations by using the method of separation of variables, the mathematical relationship between amplitude and residual stress was established. Combined with measured residual stress, the distribution of actual amplitude of thin plates could be calculated by the Siemens'amplitude-residual stress model, which coincided with the amplitude calculated by the fluid-structure interaction vibration model. The influences of fluid velocity at air pump's inlet, detecting distance and excitation frequency on amplitude were analyzed by using the fluid-structure interaction vibration model, which provides a theoretical basis for application of SI-FLAT flatness measurement systems.

In order to master the flatness characteristics of strips with different widths for ultra-wide tandem cold rolling mills, taking the sufficient flatness detection data of 1900 mm strips from 2180 mm cold rolling mills as a research object and considering the idea of big data and the cluster analysis method of data mining, this article proposed a cluster algorithm based on density and grid, applied this cluster algorithm to the analysis of flatness detection data under several typical strip widths, and then obtained the flatness characteristics of strips with different widths. A piecewise polynomial function was introduced to describe the strip flatness characteristics, and the analysis results of polynomial coefficients for strips with different widths were gotten. The proposed cluster algorithm based on density and grid and the piecewise function analysis method can be applied to analyze plenty of flatness detection data quickly and accurately, and the flatness defect characteristics and parameterized expression can be obtained, which will be a data basis of roll contour improvement and strip flatness control strategy optimization for cold rolling mills, especially ultra-wide cold rolling mills.

In order to reveal the formation mechanism of the manifested waves of cold rolled strips,the distributed dislocation was calculated by using measured residual stress,and a distributed dislocation-residual stress model was proposed. The stress field of an elastic plane with a typically distributed dislocation in the straight boundary was analyzed using the complex variable function method of plane elasticity,and the interaction was studied between the stress fields due to several straight lines with the distributed dislocation.In combination with measured data,the actual distributed dislocation which corresponds to a small relative error of residual stress was calculated in a general way. The form of the deflection function was shown by analyzing the distributed dislocation,which coincides with the actual buckling mode.