Pfefferland. Geschichten aus der Welt der Gewürze

Gewürze sind faszinierend: Sie haben Geschmack, Duft, Heilkraft und kosmetische Wirkung. Doch damit nicht genug. Gewürze sind Symbole für historische, kulturelle und soziale Klassifizierungen. Dieses Buch trägt allen Dimensionen Rechnung: Es nähert sich den Gewürzen zugleich sinnlich und wissenschaftlich. Die Autoren und Autorinnen, alle Ethnologen, folgen darum in ihren Essays vergnügt und augenzwinkernd einem ganz persönlichen Zugang zu Absinth und Rosmarin, Oregano, Gelbwurz und Petersilie. Immer aber vermitteln die Autoren auch Wissenswertes über die Herkunft, die Eigenschaften und die kulturelle Bedeutung der Gewürze. Der guten Küche verpflichtet, endet jeder Beitrag mit einem oder mehreren Rezepten, in denen das vorgestellten Gewürz eine besondere Rolle spielt.

Potassium and the excitability properties of normal human motor axons in vivo.

Hyperkalemia is an important cause of membrane depolarization in renal failure. A recent theoretical model of axonal excitability explains the effects of potassium on threshold electrotonus, but predicts changes in superexcitability in the opposite direction to those observed. To resolve this contradiction we assessed the relationship between serum potassium and motor axon excitability properties in 38 volunteers with normal potassium levels. Most threshold electrotonus measures were strongly correlated with potassium, and superexcitability decreased at higher potassium levels (P = 0.016), contrary to the existing model. Improved modelling of potassium effects was achieved by making the potassium currents obey the constant-field theory, and by making the potassium permeabilities proportional to external potassium, as has been observed in vitro. This new model also accounted well for the changes in superexcitability and other excitability measures previously reported in renal failure. These results demonstrate the importance of taking potassium levels into account when assessing axonal membrane dysfunction by excitability testing, and provide evidence that potassium currents are activated by external potassium in vivo.

Algebra of Classical Theoretical Term Reductions in the Sciences

An elementary algebra identifies conceptual and corresponding applicational limitations in John Kemeny and Paul Oppenheim’s (K-O) 1956 model of theoretical reduction in the sciences. The K-O model was once widely accepted, at least in spirit, but seems afterward to have been discredited, or in any event superceeded. Today, the K-O reduction model is seldom mentioned, except to clarify when a reduction in the Kemeny-Oppenheim sense is not intended. The present essay takes a fresh look at the basic mathematics of K-O comparative vocabulary theoretical term reductions, from historical and philosophical standpoints, as a contribution to the history of the philosophy of science. The K-O theoretical reduction model qualifies a theory replacement as a successful reduction when preconditions of explanatory adequacy and comparable systematicization are met, and there occur fewer numbers of theoretical terms identified as replicable syntax types in the most economical statement of a theory’s putative propositional truths, as compared with the theoretical term count for the theory it replaces. The challenge to the historical model developed here, to help explain its scope and limitations, involves the potential for equivocal theoretical meanings of multiple theoretical term tokens of the same syntactical type.