It didn’t bring higher education to its knees. But an effort to raise awareness about the disparity in conditions for full- and part-time faculty, “National Adjunct Walkout Day,” did make its point Wednesday — more often by word of mouth than by people actually refusing to teach a class. Many colleges rely on part-time, temporary professors to lead classes. Adjuncts account for a majority of faculty members at some campuses, and the protest was an effort to call attention to a culture that leaves many academics unsure of how much they’ll earn from year to year, without benefits or with much lower pay than full-time professors.