Open Questions and Concluding Remarks

In conclusion, I d like to enumerate a few questions regarding the chemical evolution of galaxies that seem to need further investigation. 

For abundance work in ionized nebulae, we need to understand better the effects of dust on the thermal and ionization balance. The calculated ionizing spectra from massive stars are still in a state of flux, as more physics and opacity are included this is an area that will continue to require attention as computing power grows. The effects of inhomogeneous structure on the observed emission-line spectrum of H II regions also needs to be addressed. 

Stellar nucleosynthesis also needs continuing attention. The biggest remaining problem in theoretical stellar evolution and nucleosynthesis continues to be the treatment of convective mixing, which affects both structure and nucleosynthesis. This is also a hydrodynamical problem requiring improved computing power, and should provide a source of entertainment (and argument) for some time. 

We are seeing great improvements in the study of abundances in nearby galaxies, particularly with the new space-based UV and IR observatories, which are greatly improving the data for elements besides oxygen. With these new data, we are in a better 

Donald R. Garnett Element Abundances In Nearby Galaxies 

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