TOKYO — Pubcaster NHK will offer news and entertainment shows on U.K.-based Internet TV service Joost, the partners announced on Wednesday.Offer will start with NHK’s world news program “Newsline” during the G8 summit in Japan. This summer NHK will also beam “imagine-nation,” a weekly magazine show focusing on Japanese pop culture. All programming will be free and available on demand. NHK plans to beef up its international programming next year to include English-language news. Joost is rapidly expanding its online offerings, which include 400 TV series and 1,200 feature and short pics.