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Understanding the mechanism of ion rejection in the separation process remains a major hurdle in designing new membrane materials for seawater desalination. Here, we investigate the effects of water and aromatic polyamide (PA) membrane on the rejection of salt ions, such as [Fe.sup.2+], [Na.sup.+], and [Cl.sup.-], by molecular dynamic simulations. Results demonstrate that water plays a key role in salt ion rejection because salt ions preferentially interact with water molecules to form hydrates with multishell structures, which aids the rejection of various salt ions. For Fe[Cl.sub.2] aqueous solution, the innermost shell water molecules of a [Fe.sup.2+] hydrate can hardly be replaced by other substances in their molecular dynamics simulations, so ions would be highly rejected if the effective diameter of a water channel (EDC) in the membrane is smaller than that of the innermost shell of a hydrate. However, the water molecules in the second water shell can be replaced by the atoms of the membrane when the EDC is smaller than the size of the second shell (about 9 A). Besides, although the sizes of these ions approximate to those of water molecules, the rejection level of PA membrane to salt ions is higher than that to water, which is accounted for by the formation of hydrate. POLYM. ENG. SCI., 55:466-473, 2015. © 2014 Society of Plastics Engineers, INTRODUCTION Ion separation from aqueous solution has gained considerable attention in recent years due to its extensive applications in obtaining freshwater, sewage treatment, preparation of high-purity water, etc. [1-5]. Desalinations [...]

Temperature window effect has been used to extrude polyethylene blends 5000s/TR-571 and bimodal polyethylene GC100s with low extrusion temperatures and pressures. Rheological results indicate that the temperature window effect occurs during the extrusions of the GC100s and blends 5000s/TR-571. For the blends 5000s/TR-571, both the temperature window and the minimum extrusion pressure dramatically decreases with increasing content of 5000s. For bimodal polyethylene GC100s, successive self-nucleation and annealing (SSA) fractionation results suggest that the pick at high temperature on the SSA curve of the extrudates obtained inside the temperature window is remarkably lower than those of the extrudates obtained outside the temperature window. This indicates that the lamellae of the extrudates obtained in the window are thinner than those obtained outside the window, which is attributed to the fact that the well-aligned chains as the result of structure memory effect can act as nucleating agent in the crystallization process. POLYM. ENG. SCI., 54:303-309, 2014. © 2013 Society of Plastics Engineers, INTRODUCTION Effectively processing polymer with low pressure and temperature is very beneficial in reducing the degradation, decreasing the energy consumption, and improving the product quality. For polyethylene, the conventional processing [...]

Summary: Nowadays, energy development has been plagued by such problems as the difficulty of controlling energy development and ensuring the balance of supply and demand, the serious overcapacity, and the redundancy of energy resource circulation. Blockchain technology is highly compatible with such field because of its features including decentralization, openness, independence, security, anonymity, etc. The current studies on "blockchain+energy" are focused on the application and remain insufficient on the current situation of cooperation between various subjects, with most research featuring qualitative analysis. This article employs Vosviewer for bibliometric analysis and then, from both qualitative and quantitative perspectives, provides a systematic literature review in the field of "blockchain+energy" via scientific cartography. Meanwhile, this review is diversified for also analyzing ample aspects, such as policies and regulations, national cooperation, institutional cooperation, author cooperation, research hotspots, research differences, application progress, development trend, etc. Based on the research results, policy recommendations are proposed in terms of external environment and internal technology, including one that the external environment should focus on policy support and talent cultivation, and the internal technology should focus on blockchain core technology development and security control. In this way, this article aims to provide reference for the future blockchain research, application model innovation, and relevant policy makers. [ABSTRACT FROM AUTHOR]

Long noncoding RNA (lncRNA) Cancer Susceptibility 2 (CASC2) has been proved to contribute to the development of cancers. However, the mechanism behind the action of CASC2 in thyroid cancer is not quite clear. We demonstrated that CASC2 was downregulated in thyroid cancer. We noted that CASC2 overexpression restrained the growth, migration, and invasion of thyroid cancer cells, whereas CASC2 depletion caused opposite trends. Bioinformatics analysis predicted that hypoxia inducible factor 1 subunit alpha inhibitor (FIH‐1) was potentially targeted by miR‐18a‐5p, which was confirmed by luciferase reporter assay. Upregulation of FIH‐1 abrogated the promotive effect of miR‐18a‐5p on the growth and invasion of thyroid cancer cells. In addition, CASC2 serves as a competing endogenous RNA (ceRNA) and a ''sponge'' for miR‐18a‐5p, thereby regulating the expression of FIH‐1. These data elucidated the CASC2/miR‐18a‐5p ceRNA network in thyroid cancer pathogenesis. [ABSTRACT FROM AUTHOR]

Gastric cancer ranks as the fifth most common malignant tumor worldwide and the fourth leading cause of cancer-related deaths.Human epidermal growth factor receptor 2 (HER2)-positive gastric cancer is a special type of gastric adenocarcinoma,the prognosis of which can be improved by trastuzumab plus cytotoxic chemotherapy such as cisplatin and fluorouracil.Pembrolizumab on the basis of Tmabplus chemotherapy can further improve the overall response rate,which has become the first-line standardized therapy against HER2-positive gastric cancer.However,there are still some obstacles such as the innate resistance to Tmab in specific populations.The research on HER2-targeted therapy provides clues for clinical decision-making.This review documents the current neoadjuvant and adjuvant therapies against late-stage HER2-positive gastric cancer,as well as the progress in novel HER2 pathway-targeted drugs.