Science: After a year and a half of negotiating and a 29-hour bargaining session that ended early Saturday, the union representing the more than 5000 University of California postdocs reached a tentative agreement on its groundbreaking first contract. Among the decisions were the adoption of the pay scale used for postdocs funded by the National Institutes of Health, wage increases, and layoff protections. If approved, the contract will bring “definite economic improvements and important gains in rights, protections, and working conditions,” according to union spokesman Matthew O’Connor.