Access to Health

Access to health is an often-overlooked aspect of the right to health. Without practical access, the right to health becomes an empty promise. International human rights conventions and declarations do not directly mention access to health, but the above comment on the International Covenant on Economic, Social, and Cultural Rights does address the issue

Tuning Exchange Bias in Core/Shell FeO/Fe₃O₄ Nanoparticles

Monodisperse 35 nm FeO nanoparticles (NPs) were synthesized and oxidized in a dry air atmosphere into core/shell FeO/Fe₃O₄ NPs with both FeO core and Fe₃O₄ shell dimensions controlled by reaction temperature and time. Temperature-dependent magnetic properties were studied on FeO/Fe₃O₄ NPs obtained from the FeO NPs oxidized at 60 and 100 °C for 30 min. A large exchange bias (shift in the hysteresis loop) was observed in these core/shell NPs. The relative dimensions of the core and shell determine not only the coercivity and exchange field but also the dominant reversal mechanism of the ferrimagnetic Fe₃O₄ component. This is the first time demonstration of tuning exchange bias and of controlling asymmetric magnetization reversal in FeO/Fe₃O₄ NPs with antiferromagnetic core and ferrimagnetic shell