"temperament" among races. In 1910, the Journal published an article by Ulysses G. Weatherly (1865–1940) that called for white supremacy and segregation of the races to protect racial purity. W. E. B. Du Bois (1868–1963), one of the first African-American sociologists, was the first sociologist to use sociological concepts and empirical research methods to analyze race as a social construct instead of a biological reality. Beginning in 1899 with his book The Philadelphia Negro, Du Bois studied and wrote about race and racism throughout his career. In his work, he contended that social class, colonialism, and capitalism shaped ideas about race and racial categories. Social scientists largely abandoned scientific racism and biological reasons for racial categorization schemes by the 1930s. Other early sociologists, especially those associated with the Chicago School, joined Du Bois in theorizing race as a socially constructed fact. By 1978, William Julius Wilson argued that race and racial classification systems were declining in significance, and that instead, social class more accurately described what sociologists had earlier understood as race. By 1986, sociologists Michael Omi and Howard Winant successfully introduced the concept of racial formation to describe the process by which racial categories are created. Omi and Winant assert that "there is no biological basis for distinguishing among human groups along the lines of race." Eduardo Bonilla-Silva, Sociology professor at Duke University, remarks, "I contend that racism is, more than anything else, a matter of group power; it is about a dominant racial group (whites) striving to maintain its systemic advantages and minorities fighting to subvert the racial status quo." The types of practices that take place under this new color-blind racism is subtle, institutionalized, and supposedly not racial. Color-blind racism thrives on the idea that race is no longer an issue in the United States. There are contradictions between the alleged color-blindness of most whites and the persistence of a color-coded system of inequality. Today, sociologists generally understand race and racial categories as socially constructed, and reject racial categorization schemes that depend on biological differences. Political and practical uses Biomedicine In the United States, federal government policy promotes the use of racially categorized data to identify and address health disparities between racial or ethnic groups. In clinical settings, race has sometimes been considered in the diagnosis and treatment of medical conditions. Doctors have noted that some medical conditions are more prevalent in certain racial or ethnic groups