Standardize research study summaries

[jinlx]

Summary

• convert every Research-page theme into a concise, labeled bullet list
• use consistent categories such as research question, approach, key finding, interpretation, and contribution
• apply the same scannable treatment to ozone isopleths and aged-smoke health research
• preserve the source-to-receptor order and all related-work links

Why

The page's section order is logical, but its presentation mixed paragraphs and bullets. A consistent study-summary format makes methods, findings, and implications easier to scan and compare.

Impact

Each research theme now communicates its purpose, methods, and contribution at a glance while retaining the scientific qualifications needed for OH exposure, ozone regimes, satellite transects, and health interpretation.

Validation

• reviewed all seven study summaries for parallel structure
• checked heading and bullet formatting
• checked the diff for whitespace errors
• GitHub's Site checks workflow will perform the full Jekyll build and internal-link check