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Prolactin is an important endocrine activator of lactogenesis. This study investigated the function and mechanism of miR-135b in the enhancement of lactation by prolactin in goat mammary epithelial tissue. We utilized S-Poly (T) sequencing to evaluate changes in gene regulation in the goat mammary gland after incubation with 2.5 μg/ml prolactin and 2.5 μg/ml IGF-1 by examining highly expressed miRNAs during early lactation and late-lactation. The results illustrated that miR-135b is highly expressed in the goat mammary gland during early lactation and late-lactation, and also after treatment with 2.5 μg/ml prolactin and 2.5 μg/ml IGF-1. We used Q-RT PCR, Western Blot, immunofluorescence, and luciferase reporter assay analysis, and found that PRL was significantly down-regulated in response to the expression of miR-135b in a manner that was functionally related to TAG synthesis via the large tumor suppressor 2 gene (Lats2), an important regulator of adipocyte proliferation via Hippo Signaling. Furthermore, using bisulfite-sequencing PCR (BSP), Q-PCR, and Western Blot we discovered an increase in expression of DNMT I (DNA methyl transferase I) in goat mammary epithelial cells with the 2.5 μg/ml PRL incubation, which led to DNA methylation of the CpG island upstream of miR-135b and inhibited the transcription and expression of miR-135b. K E Y W O R D Sfat metabolism, LATS2, methylation, miR-135b | INTRODUCTIONMilk provides optimal nutrition for growth and development of humans. Compared with cow milk, goat milk (the milk of Capra hircus) has a higher level of unsaturated fatty acids, total fat, calcium, vitamins, carbohydrates, and proteins (Han et al., 2004;Hinrichs, 2004;Luna, Bach, Juarez, & de la Fuente, 2008;Qu, Chen, Fan, Sun, & Zeng, 2016).Prolactin (PRL) plays a key role in the process of lactation and is secreted by the hypothalamus. PRL is an important hormone for the initiation of lactation in ruminants, can stimulate mammary epithelial cell metabolism, and stimulate milk protein synthesis (Inaba et al., 2016). In non-ruminants, PRL promotes mammary development during early pregnancy by stimulation of the ovaries to produce estrogen and progesterone (Campo Verde Arbocco et al., 2016).During pregnancy, PRL concentrations in plasma are significantly elevated and it can promote the secretion of IGF 1 and enhance the activity of the PKB/AKt (protein kinase) pathway (Roman, Seres, Herichova, Zeman, & Jurcovicova, 2003; Milewicz et al., 2011;Xiong et al., 2016). In addition, PRL-PRLR complexes (PRL combined with PRLR) can enter cells and elicit physiological effects through the JAK/ STAT and PKB/AKt pathway (Akers, 2006). Numerous studies have revealed that PRL plays an indispensable role in the process of lactation. However, how PRL works at the molecular level and the related molecular mechanism remain a "black box" that requires careful research (Akers, 2006;Erb et al., 1976;Hart, Bines, Morant, & Ridley, 1978;Kazmer & Oyler, 1991 Wang et al., 2014). MiRNA regulation is precise and its expression has stri...

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A novel buckling-induced forming method is proposed to produce metal bellows. The tube billet is firstly treated by local heating and cooling, and the axial loading is applied on both ends of the tube, then the buckling occurs at the designated position and forms a convolution. In this paper, a forming apparatus is designed and developed to produce both discontinuous and continuous bellows of 304 stainless steel, and their characteristics are discussed respectively. Furthermore, the influences of process parameters and geometric parameters on the final convolution profile are deeply studied based on FEM analysis. The results suggest that the steel bellows fabricated by the presented buckling-induced forming method have a uniform shape and no obvious reduction of wall thickness. Meanwhile, the forming force required in the process is quite small.

Offshore wind energy resources far exceed those on land. However, the increase in water depth of the continental shelf in China’s sea area slows down as the distance from the shore increases. In view of the characteristics of China’s sea, how to optimize the design of mooring systems to adapt to the water depth conditions in China’s waters and to resist the harsh sea conditions is one of the major problems encountered in the development of floating wind turbines. In this paper, the 5MW-OC4 semi-submersible floating wind turbine is taken as the research object, and the frequency domain and time domain calculation of the floating wind turbine are carried out by using SESAM software under the water depth of 40 m in the Bohai Sea and by comparing the motion response and tension of the catenary and tension of the mooring floating wind turbines. The mooring system is optimized by combining the buoy and clump weight. The results show that the catenary mooring mode is more suitable for the floating wind turbine under shallow water conditions. Mooring accessories used in combination have the same effect on the overall response of the floating wind turbine as changing the same mooring parameters when used alone, but the effect of changing the mooring parameters on the performance optimization of the mooring system is more obvious when used in combination, and a reasonable combination of accessories can significantly change the overall characteristics of the floating system and affect the safety and cost of the system.