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Permeability variation in ground formation, which is caused by the changes in geometrical conditions, has attracted a significant amount of attention in various industrial applications. However, a practical and reliable method has not been proposed yet owing to the extremely complex grain shapes, micron-scale pore paths, lack of reliable testing apparatus, and methods that further complicate its practical implementation. Therefore, the pore-scale simulation (PSS) method was adopted herein to examine the permeability variation characteristics of changes in the geometrical conditions with a focus on their correlations with key geometrical variables. Two kinds of PSS series models, i.e., five simple and four complex structured porous media, were built and analyzed to investigate the permeability variation aspects according to the changes in geometrical conditions. Consequently, the fundamental relation between permeability variation and key geometrical variables, such as specific surface area, porosity, and bulk volume, were successfully presented. Particularly, the relations between the two practical permeability variations as the respective functions of either the specific surface area or porosity, coupled with changes in the bulk volume, were derived and verified by analyzing both PSS models. In conclusion, the reliability of the derived relations for various kinds of porous flow analyses accompanying geometrical changes was checked. Moreover, it was shown that the permeability variations by changes in the geometrical conditions are better correlated with specific surface area and bulk volume but are scarcely expressed as a sole function of porosity. [ABSTRACT FROM AUTHOR]

Facile homo‐coupling of terminal alkynes, which generates conjugated diynes, is an undesired pathway in the development of transition‐metal‐catalyzed oxidative C–H functionalization of (hetero)arenes with terminal alkynes. By incorporating this process into a catalytic cycle, we achieved regio‐ and stereoselective hydroarylation of nitropyrazoles with the resulting 1,3‐diynes. A simple change in the stoichiometry and oxidant allowed direct C–H alkynylation of nitropyrazoles, producing the corresponding alkynyl pyrazoles. [ABSTRACT FROM AUTHOR]

Lysophosphatidic acid (LPA) has been implicated in the pathology of human ovarian cancer. This phospholipid elicits a wide range of cancer cell responses, such as proliferation, trans-differentiation, migration, and invasion, via various G-protein-coupled LPA receptors (LPARs). Here, we explored the cellular signaling pathway via which LPA induces migration of ovarian cancer cells. LPA induced robust phosphorylation of ezrin/radixin/moesin (ERM) proteins, which are membrane-cytoskeleton linkers, in the ovarian cancer cell line OVCAR-3. Among the LPAR subtypes expressed in these cells, LPA 1 and LPA 2 , but not LPA 3 , induced phosphorylation of ERM proteins at their C-termini. This phosphorylation was dependent on the Gα 12/13 /RhoA pathway, but not on the Gα q /Ca 2+ /PKC or Gα s /adenylate cyclase/PKA pathway. The activated ERM proteins mediated cytoskeletal reorganization and formation of membrane protrusions in OVCAR-3 cells. Importantly, LPA-induced migration of OVCAR-3 cells was completely abolished not only by gene silencing of LPA 1 or LPA 2 , but also by overexpression of a dominant negative ezrin mutant (ezrin-T567A). Taken together, this study demonstrates that the LPA 1 /LPA 2 /ERM pathway mediates LPA-induced migration of ovarian cancer cells. These findings may provide a potential therapeutic target to prevent metastatic progression of ovarian cancer. [ABSTRACT FROM AUTHOR]