The Amistad Street Building in New Haven, Connecticut, where the body of Yale University grad student Annie Le was found Sunday, was closed again today. Officials have named scientists as "point persons" to act as liaisons between the police and researchers who need to gain access. Security is extremely tight; anyone who enters has to be escorted by a police person. A source at Yale adds that technicians are being allowed to enter for 2 hours at a time to care for research mice and maintain cell strains. Med School Dean Robert Alpern said that access to the basement, where Le was found, is particularly restrictive because it contains animal facilities. The university is keeping people informed here. University Vice President Linda Lorimer said she hoped the building would be open Wednesday.