Searching for the major finding
Generally speaking, when I begin looking at a scholarly article I might read the Abstract first to get a sense of what it is about. However, depending on the writing style, this might not be as helpful as it should. For this example, I'm going to skip that step and instead scroll down to the end of the article to look at the Conclusion (p. 1769), where I can find the author's final thoughts about their research. Here, I see the following finding:
"Second, we find that counties with the worst PM2.5 air quality are characterized by a statistically significant larger percent of NHB, smaller percent of people over 64 years of age, larger percent of people in poverty, and, for daily PM2.5 only, more people per county."
Immediately, I see two unfamiliar terms: NHB and PM2.5. However, I can still understand that air quality is worse in areas where there are fewer elderly people (64+ years old) and more poor people. I don't know precisely what 'worse' means yet and there are some other details that I don't yet understand.
A quick and easy tip for finding out what NHB and PM2.5 mean is to search the beginning of the article to find where the terms are defined. With pdfs or electronic copies of articles, a quick way to do this is to hit Ctrl+f which will open a finder widget where I can type in the terms. If I search for NHB, I find that on page 1759, under the heading 2.3. Demographic Data, the term is defined as:
"non-Hispanic black (NHB)"
If I do the same for PM2.5, it is a little more tricky. The first time the word appears (on p. 1755, in the abstract) there is no indication of what it means. when I look at the second occurrence, I see:
"including particulate matter (PM10 and PM2.5)."
The next occurrence is:
"including fine particulate matter (PM2.5)."