https://www.selleckchem.com/products/beta-estradiol-17-acetate.html Propane retention factors with HKUST-1-coated μGC and a state-of-the-art polar, porous-layer open-tubular (PLOT) stationary phase were approximately the same at ~7.5. However, with polar methanol, retention factors with these two stationary phases were 748 and 59, respectively, yielding methanol-to-propane selectivity factors of ~100 and ~8, respectively, a 13-fold increase in polarity with HKUST-1. These studies advance the applications of MOFs as μGC stationary phase. © The Author(s) 2020. Published by Oxford University Press. All rights reserved. For permissions, please email journals.permissions@oup.com.Hyperkalemic periodic paralysis (HyperKPP) manifests as stiffness or subclinical myotonic discharges before or during periods of episodic muscle weakness or paralysis. Ingestion of Ca2+ alleviates HyperKPP symptoms, but the mechanism is unknown because lowering extracellular [Ca2+] ([Ca2+]e) has no effect on force development in normal muscles under normal conditions. Lowering [Ca2+]e, however, is known to increase the inactivation of voltage-gated cation channels, especially when the membrane is depolarized. Two hypotheses were tested (1) lowering [Ca2+]e depresses force in normal muscles under conditions that depolarize the cell membrane; and (2) HyperKPP muscles have a greater sensitivity to low Ca2+-induced force depression because many fibers are depolarized, even at a normal [K+]e. In wild type muscles, lowering [Ca2+]e from 2.4 to 0.3 mM had little effect on tetanic force and membrane excitability at a normal K+ concentration of 4.7 mM, whereas it significantly enhanced K+-induced depression of force and membrane excitability. In HyperKPP muscles, lowering [Ca2+]e enhanced the K+-induced loss of force and membrane excitability not only at elevated [K+]e but also at 4.7 mM K+. Lowering [Ca2+]e increased the incidence of generating fast and transient contractures and gave rise to a slower in