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Simple parameterizations of droplet effective radius in stratiform and convective clouds are presented for use in global climate models. Datasets from subtropical marine stratocumulus, continental and maritime convective clouds, and hill cap clouds in middle latitudes and a small amount of data from stratocumulus clouds in middle latitudes have been examined. The results suggest strongly that a simple relationship exists between droplet effective radius and liquid water content in layer clouds with the droplet effective radius proportional to the cube root of the liquid water content. The constant of proportionality is different over oceans and continents. In current global climate models liquid water content is not a predicted variable in convective clouds, and the data strongly suggest that a fixed value of droplet effective radius between 9 and 10 [[micro]meter] should be used for continental clouds more than 500m deep and 16 [[micro]meter] for maritime cumulus more than 1.5 km deep.

A new scenario for solar flare eruption in the coronal holes is analyzed by using MHD stability concepts for a spheromak configuration. The stability properties of a spheromak partially embedded into a conducting surface are studied using three dimensional MHD simulations. In agreement with the analytical theory, a large degree of line-tying stabilizes the spheromak's tilt instability, while the elongation has a destabilizing effect. High-resolution nonlinear simulations also demonstrate current sheet formation at the upper surface of the spheromak, where the tilted magnetic field of the spheromak reconnects with the background magnetic field. The calculated stability threshold and the observed magnetic reconnection support a model of coronal jet eruptions where a dome-like magnetic structure grows through flux emergence on the solar surface, tilts, reconnects, and erupts. Countering the effect from elongation, line-tying strongly stabilizes a spheromak growing from a flux-emergence process, suggesting that to accelerate the onset of eruptive coronal jets, there must be magnetic reconnection at the bottom of the spheromak to detach the structure from the solar surface. [ABSTRACT FROM AUTHOR]

Anabolic-androgenic steroids are synthetic derivatives of testosterone. They are thought to be the most commonly used performance and image-enhancing drugs (PIEDs) in Australia. However, the motivations for men's use of steroids and other PIEDs are poorly understood. Established ways of understanding these motivations highlight men's performance and/or image-related concerns, in the context of contemporary masculinities and gender norms. Researchers have paid little attention to how the social and political features of testosterone shape and transform steroid use. Instead, testosterone tends to be taken for granted as a 'messenger of sex' that acts on the body in predictable and routinised ways. This article takes a different approach. Drawing on feminist science studies and interviews conducted for an Australian research project, we investigate how the cultural and symbolic meanings assigned to testosterone shape the ontological politics of men's steroid consumption. Approaching testosterone as an emergent social and biopolitical gathering rather than as a stable sex hormone allows us to better understand how men's PIED consumption is mediated, particularly by pervasive ideas about sexual difference and the biology of gender. In concluding, we consider ways of better engaging men who consume steroids in health initiatives, in keeping with their concerns and perspectives. [ABSTRACT FROM AUTHOR]