Solar proton events (SPEs) are known to have caused changes in constituents in the Earth's polar neutral middle atmosphere.
We hypothesized that the implementation of resident duty hour limitations have caused changes in otolaryngology training programs in the United States.
Patterns of cropland and the driving factors that have caused changes in those patterns differ substantially among regions.
The extra ultraviolet light is believed to have caused changes to plankton, but the sparse wildlife in Antarctica, such as penguins, have not been severely affected by the ozone hole.
Rapid urban growth and urbanization in recent decades have caused changes in the structure of human habitations such as social and economic changes that would further clarify the importance of sustainable development and urban sustainability.
Population pressure and the ensuing expansion of agriculture to more marginal land, intensification of the homegarden system, together with climate changes affecting the water supplies, have caused changes in farmers' livelihoods.
The changes in land tenure have caused changes in land-use practice in Amboseli ecosystem (Okello 2012) reducing the vast grazing land.
These levels of CO2 and other greenhouse gases (GHGs) have caused changes in climate that in turn have had widespread impacts on human and natural systems [2].
Specifically, the nation's post-9/11 racial environment may not have caused changes in racial identity selection of Arab and Islamic Americans; rather, it may have caused changes in the type of immigrants coming to America - within ancestral groups, encouraging relatively more immigrants who are likely to select a non-white racial identity.
The changes in the stored biosolids might have caused changes in nutrient availability, which in turn caused microbial populations to differ from year to year, ultimately affecting nematode populations.
