Yes, by reducing other budget items, as long as you do not change the total granted to the R&D project or institution.
Regarding the costs involved, the funding institutions are obliged to pay for the beneficiaries’ contributions corresponding to the 1st scale of earnings mentioned in Article 36 of Decree-Law 40/89, of February 1st; if beneficiaries wish to be covered by a higher scale, they are responsible for paying the difference. The costs regarding the personal accident insurance depend on the contract the institution awarding the grant concludes with the insurance company.