This week in Minneapolis, 3,000 public-health experts will attend the biennial National Conference on Tobacco or Health. Since the release of the landmark 1964 Surgeon General's report, considerable progress has been made in reducing the prevalence of smoking among adults -- from more than 40 percent to 21 percent (20 percent in Minnesota) -- through educational campaigns in the mass media and through the passage of clean-indoor-air laws (the first of which was authored by Minnesota state Rep. Phyllis Kahn in 1975). Yet nearly 50 million Americans still smoke, and cigarettes remain the leading preventable cause of lung cancer, heart disease and emphysema. Most worrisome is that the decline in smoking among high-school students has leveled off at 22 percent. One wrenching controversy that attendees at this week's conference will debate is whether the tobacco industry is indeed on the wane or is still up to its old tricks. Dr. Alan Blum, director of the University of Alabama Center for the Study of Tobacco and Society, teamed up with cartoonist Matt Bors to create this view of one company's attempt to soften its image.