A side-by-side comparison of different capacitation media in developing mouse sperm fertilizing ability.

To acquire the ability to fertilize the egg, mammalian spermatozoa must undergo a series of changes occurring within the highly synchronized and specialized environment of the female reproductive tract, collectively known as capacitation. In an attempt to replicate this process in vitro, various culture media for mouse sperm were formulated over the past decades, sharing a similar overall composition but differing mainly in ion concentrations and metabolic substrates. The widespread use of the different media to study the mechanisms of capacitation might hinder a comprehensive understanding of this process, as the medium could become a confounding variable in the analysis.

Art, fact and artifact: reflections on the cross-talk between theory and experiment.

With the increasing sophistication of each, theory and experiment have become highly specialized endeavors conducted by separate research groups. A result has been a weakening of the coupling between them and occasional hostility. Examples are given and suggestions are offered for strengthening the traditional synergy between theory and experiment.

Emergence of Linnett's "double quartets" from a model of "Lewis dots".

Chemists routinely explicate molecular structures and chemical reactions in terms of the propensities of semiclassical valence electrons (aka "Lewis dots"). Typically, the electrons are viewed as forming spin pairs and recent efforts to translate this concise and intuitive qualitative picture into an efficient and relatable quantitative model have made good progress. But electrons are not always paired and advanced quantum calculations have shown that this is so even in small diamagnetic species such as dicarbon and benzene.