A new multifunctional protein kinase, which normally exists as an inactive form in the soluble fraction in mammalian tissues, attaches to membranes to exhibit full enzymatic activity. A low concentration of Ca2+ is absolutely necessary for this activation. This process is reversible. cAMP shows no effect. The active factors in membranes are phosphatidylinositol, phosphatidylserine, phosphatidic acid, diphosphatidylglycerol, and phosphatidylethanolamine in that order. Phosphatidylcholine and sphingomyelin are far less effective. Cytoplasmic as well as other membrane fractions from various tissues are active in supporting the enzymatic activity. A possible role of this Ca2+ and phospholipid-activated protein kinase system in transmembrane control is proposed.

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Production of polypropylene (PP) nanofibers below 1 μm in average diameter is difficult with conventional melt‐spinning. A nozzle‐free melt‐type electrospinning (M‐ESP) system with a line‐like CO2 laser beam melting device were used to produce PP nanofibers. To achieve the purpose, core [poly(ethylene‐co‐vinyl alcohol) (EVOH)]–clad (PP) nanofibers (average diameter, 0.88 μm) were fabricated from PP/EVOH/PP three‐layer films using the M‐ESP. The core–clad structure was formed by a wrapping phenomenon caused by the difference in the melt flow rates (MFRs) of PP and EVOH melts. Hollow PP nanofibers were obtained from the core–clad nanofibers by extraction of EVOH. Nanofiber diameter and hollow wall thickness could be altered by changing the MFR of the PP melt. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46393.