The Corporation for Public Broadcasting, the congressionally chartered non-profit that helps keep TV and radio programming like “Sesame Street,” “Downton Abbey” and “All Things Considered” on the air, has laid off a dozen employees and is requiring week-long furloughs for senior staff,  the web site, Current.org, is reporting. The organization is also eliminating three vacant positions; all told, the downsizing cuts its workforce by 11 percent. The reductions are largely due to the sequester, according to what a spokesman told the site. Like most federal agencies, the corporation is having to absorb about a 5 percent budget cut. Between that…