Many researchers investigate the biogeochemical cycles of chemical elements such as carbon, oxygen, nitrogen, phosphorus and sulfur, as well as their stable isotopes.

Researchers investigated how emotions such as happiness, pain, stress, sadness and fatigue varied during travel and by travel methods.

Instead of looking at the organisational context, some researchers investigate the intra-firm aspects at personal level of organisational knowledge networks, where knowledge management processes start and end.

Word recognition would be no doubt the most essential process of bilingual lexical access in language comprehension, in which researchers investigate the selective or non-selective recognition of isolated words.

Researchers investigating the impact of humor must also control for various other issues.