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The electrospinning of poly(L-lactic acid)/poly(D-lactic acid) (PLLA/PDLA) microfiber membranes were carried out with dichloromethane (DCM), DCM/ethanol, DCM/acetone, DCM/hexane as the spinning solvent. Scanning electron microscope observation showed that the electrospun fiber obtained using DCM/ethanol (L/D-DE) mixed solvent was homogeneous without visible bead, which was better than any others. Moreover, plenty of pores could be found on the surface of the fibers obtained using the mixed solvents. The porous structure of fibers was significantly influenced by the ethanol (non-solvent) content. When the DCM/ethanol was 50:10 (v/v), the fibers were uniform and had isolated pores. XRD and DSC results indicated that the exclusive stereocomplex poly(lactide acid) (sc-PLA) crystallites without any homocrystallites poly(lactide acid) (hc-PLA) did form in all types of fibers. The crystallinity of sc-PLA in the L/D-DE fiber was higher than other samples due to the slowest evaporation rate. TGA test further indicated that the thermal stabilities of PLLA/PDLA electrospun fibers were slightly better than the PLLA. Furthermore, L/D-DE had the excellent mechanical properties and underwent the course of ductile fracture. Possible mechanisms accounting for the morphologies and tensile properties were also proposed in this study.

Background: The existence of liver cancer stem cells (LCSCs) and the occurrence of epithelial-mesenchymal transition (EMT) are generally considered to be the primary causes for migration and metastasis of Hepatocellular carcinoma (HCC). Accumulating evidences demonstrate that tRFs and tiRNAs, are an emerging category of regulatory RNA molecules derived from transfer RNA (tRNA), are dysregulated in in various human cancer types and play crucial roles. However, their impact on tumorigenesis is still in the exploratory stage, their roles and mechanisms in HCC and LCSCs are still unknown.Methods: Quantitative real-time PCR (qRT-PCR) was performed to detect the expression of glycine tRNA-derived fragments (Gly-tRF) in HCC cell lines and tumor tissues. Inhibitor and mimic were performed to weaken and enhance the function of Gly-tRF. Flow cytometry and sphere formation assay to detect the representative surface markers (CD133, CD13, EpCAM, CD44) proportion and stemness of LCSCs. Transwell assay and scratched wound assay were performed to detect HCC cells migration. Western blot was used to detect the expression of EMT-related proteins. Dual luciferase reporter assay and signaling pathway analysis were performed to explore the underlying mechanism of Gly-tRF functions.Results: Gly-tRF is highly expressed in HCC cell lines and tumor tissues, compared to L02 hepatocytes and adjacent normal tissues. Flow cytometry and sphere formation assay found that Gly-tRF mimic promotes LCSCs subpopulation proportion and LCSCs-like cells stemness. Next, functional experiments confirmed that Gly-tRF mimic promotes HCC cells migration and EMT. Consistently, Loss of Gly-tRF inhibits HCC cells migration and EMT. Mechanistically, Gly-tRF inhibits the level of NDFIP2 mRNA by binding to the NDFIP2 3′ UTR. Importantly, overexpression of NDFIP2 can weaken the effect of Gly-tRF in promoting LCSCs-like cells sphere formation and HCC cells migration, NDFIP2 is the direct target of Gly-tRF. Signaling pathway exploration found that Gly-tRF enhances the abundance of phosphorylated AKT.Conclusions: Gly-tRF promotes EMT of HCC cells and enhances LCSCs-like cells stemness via targeting NDFIP2 and activating AKT signaling pathway. The tRNA-derived fragments provide a new perspective of oncology research, and can be the direction of future oncology research.

In order to safeguard their own energy security, strengthen environmental protection and prevent climate change, many countries in the world are vigorously developing renewable energy to replace traditional fossil energy. As the largest developing country in the world, China’s energy structure and development situation are in a very serious situation, and the energy security problems are threatening the smooth implementation of the national energy strategy. Accelerating the development and utilization of renewable energy has become the best choice to solve the energy crisis in China. Wind and solar energy, as an important part of new energy, are gradually infiltrating into China’s power system. However, due to their great randomness, they are bound to bring severe challenges and a series of difficulties to the traditional power system optimal scheduling problem. China is rich in water energy resources, hydropower is the largest renewable energy that can be developed on a large scale at present, vigorously developing hydropower can significantly reduce the consumption of traditional fossil energy, and at the same time it will absorb some negative effects of new energy power generation through controllable adjustment. Therefore, it is necessary to rationally formulate the optimal dispatching strategy of multi-energy complementary power system for the development of China’s energy strategy. This paper has carried on a series of discussions and carried out the following work. (1) Comprehensively analyze the reasons for the uncertainty of new energy power generation, study the probability distribution model of prediction error, and discuss the new energy power generation scenario with the scenario analysis method. (2) The traditional combined optimal dispatching model, the combined dispatching model with new energy generation system and the multi-energy complementary power system are calculated respectively, and the optimal dispatching strategy is given through an example analysis. (3) Complex models need efficient algorithms to solve, so this paper proposes a new intelligent optimization algorithm.

Neuropilin-1 (NRP1) is a type I transmembrane glycoprotein that was originally found playing a role in neuronal axon guidance and embryonic angiogenesis. NRP1 can promote various aspects of tumorigenesis, such as angiogenesis, cell survival, migration, invasion and chemo-resistance, but little is known about the nanomechanica signature of NRP1 inregulating hepatocellular carcinoma(HCC) cells. Our study found that NRP1 was overexpressed in HCC and high expression of NRP1 was associated with poor prognosis in HCC patients.but there are no correlation between NRP1 and liver cirrhosis. In vivo and vitro experiments knockdown of NRP1 reduced proliferation and invasion of HCC. We quantified the Young's modulus, RMS residuals of HCC cell lines and normal liver cell line L02 using Atomic force microscopy (AFM). AFM data indicated that Young's modulus decreased in highly metastatic HCC cells, which is consistent with the verification results of NRP1 knockdown. Our analyses revealed that down regulation of NRP1 negatively correlated with increased Young's modulus in cells exhibiting differing degrees of invasiveness. Our molecular data showed that NRP1 activated AKT, ERK1/2, and epithelial-mesenchymal transition (EMT)-related signals in HCC cells and promoted tumor apoptosis and invasion. As an important biophysical property of cells, the membrane stiffness of HCC cells was further quantified by AFM force measurements, which indicated that these cells became much stiffer after NRP1 knockdown. These results collectively illuminated that Neuropilin-1 alterrated namomechanica signature in hepatocellular carcinoma cells and can be a potential therapeutic agent for HCC. Funding Statement: The present study was supported by the National Natural Science Fund of China (grant nos. 31570509 and 81702326), Science and Technology Major Project of Gansu province(1602FKDA001), the Talent innovation and Entrepreneurship Program of Lanzhou City (grant no. 2016-RC57) and the science and technology project of Chenguan District (2017SHFZ0014); Declaration of Interests: The authors declare no conflicts of interest. Ethics Approval Statement: The study was approved by the Zhongshan Hospital Ethics Committee and informed consent was obtained from each patient under Institutional Reviewer Board protocols. The study protocol conforms to the ethical guidelines of the 1975 Declaration of Helsinki as reflected in a prior approval by the institution's human research committee.

In recent years, with the continuous development of China's social and economic life of the people in the industry has been rapid infrastructure development. In these people's livelihood industries, the pace of development of the power industry is particularly fast. With the continuous improvement and continuous development of society and the improvement of people's living standards, electrical equipment has become an indispensable part of our lives, but what good foundation, a growing number of power system to enhance and improve our lives At the same time, there are many attendant problems, China's various regions have experienced varying degrees of power shortage problem, in order to alleviate the power shortage situation in the country and even less in some areas have taken brownouts and blackouts solutions. The relay technology has just the right solution to this thorny problem, the principle of protection technology, when the power system for some reason there is a problem, relay technology can automatically be repaired, so that the power system can stable and secure operation, which has a strong automation features. The protection of these power systems, the protection technology is a very important measure[1].