WASHINGTON — Nearly all of the Obama administration’s science staff has departed the White House since January, and the Trump administration has moved slowly to replace them. In the meantime, however, an unofficial shadow office, stocked with Obama loyalists, is quietly at work. The network, described to STAT by officials from the previous administration who are involved, is informal yet organized, allowing for a far-reaching if largely inconspicuous effort to continue advocating for the Obama science agenda. Participants have provided counsel to Democratic lawmakers and their staffs on Capitol Hill, and they have held group-wide strategy sessions much in the...