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The development of functional therapies for corneal repair and regeneration is a pressing issue. Corneal stroma provides the principal functions of the cornea. However, because of the highly organized nature of the stromal matrix, the attempts to reproduce corneal stroma might follow a scar model. Here, we have developed a protocol for the efficient generation of a cell-laden and orthogonal-multilayer tissue-engineered (TE) corneal stroma, which is induced by the mechanical effects of compressed collagen (CC) or stretched compressed collagen (SCC). Within SCC, with applied compression and force extension, collagen microfibres and corneal stromal cells (CSCs) are arranged orderly, while collagen fibres and CSCs in CC are randomly arranged. Dehydrated SCC has higher tensile strength than dehydrated CC. Hydrated SCC has similar transparency with hydrated native corneal stroma. Compared with those cultured on tissue culture plates (TCP), down-regulation of the genes and proteins of cytoskeleton, activation, proliferation, collagen and TRPV4 , up-regulation of proteoglycans, gap junction proteins and TRPA1 are in CSCs of CC and SCC. Moreover, SCC and CC grafts displayed biocompatibility and integration with host corneal tissue after rabbit intra-corneal stromal transplantation by wk 6 under slit lamp microscopy, in vivo confocal microscopy and histological examination. The SCC model facilitates the construction of physiological feature TE corneal stroma, which serves as a foundation for physiological TE construction of other tissues. Statement of Significance The development of functional therapies for corneal repair and regeneration is a pressing issue. Corneal stroma provides the principal functions of the cornea. Here, we have developed a protocol for the efficient generation of a cell-laden and orthogonal-multilayer tissue-engineered (TE) corneal stroma, which is induced by the mechanical effects of compressed collagen (CC) or stretched compressed collagen (SCC). These models facilitate the construction of physiological feature TE corneal stroma, which serves as a foundation for physiological TE construction of other tissues and helps to reverse fibrosis pathologies in general. [ABSTRACT FROM AUTHOR]

Improving water-saving irrigation technology and water use efficiency are often regarded as effective ways to control the amount of agricultural water consumption, but the rebound effect may offset this effort in practice. Based on the sample of 30 provinces in China from 2000 to 2017, this paper applies the meta frontier data envelopment analysis method to measure agricultural water efficiency, and then estimates the rebound rate of agricultural water resource applying difference-generalized method of moments and elasticity analysis formula. Further, the difference-in-difference model is used to test the effectiveness of China's water rights reform on China's agricultural water rebound rate in recent years. The results show that: (1) Within the survey period, the average agricultural water rebound rate of China in short-term and long-term were 0.49 and 0.66 respectively, and the water rebound rate in all provinces were positive, indicating that water rebound effect was widespread in China's agricultural water market; (2) Agricultural water rebound rates were significantly different among regions, which was higher in western region while were comparatively smaller in the eastern and central regions; (3) The water rights pilot project failed to restrain the rebound of agricultural water use, but promoted it, which may be resulted from the market frictions of water trade. According to the results, recommendations are put forward for the governments to reinforce management of water, improve water rights system and reduce trade costs, in order to reduce the friction of agricultural water market and the effective use of water resource. • We used meta frontier DEA to measure agricultural water efficiency. • We estimated agricultural water rebound rates in the short and long run. • The effectiveness of China's water rights reform is tested. [ABSTRACT FROM AUTHOR]