DIMER at 50:

Oxygen concentrators performance with nitrous oxide at 50:50 volume.

BACKGROUND AND OBJECTIVES Few investigations have addressed the safety of oxygen from concentrators for use in anesthesia in association with nitrous oxide. This study evaluated the percent of oxygen from a concentrator in association with nitrous oxide in a semi-closed rebreathing circuit. METHODS Adult patients undergoing low risk surgery were randomly allocated into two groups, receiving a...

Celebrating the ACIP at 50.

In this issue, Walton, Orenstein, and Pickering provide a useul summary of the 50-year history of the Advisory Committee n Immunization Practices (ACIP). When the ACIP was formed in 964, immunization recommendations for children were primarily eveloped by the American Academy of Pediatrics (AAP), with the merican Public Health Association and other professional organiations also providing recom...

Hematopoietic-cell transplantation at 50.

Medicare at 50--moving forward.

Synopsis The Medicare program must contend with serious challenges as it enters its 50th anniversary year, including rising expenditures, a fragmented, confusing benefit structure, and inadequate financial protections for some low-income beneficiaries and high users of services. In part 2 of their report, David Blumenthal, M.D., Karen Davis, and Stuart Guterman examine these challenges and disc...

Tverberg ’ s Theorem at 50 :

We describe how a powerful new “constraint method” yields many different extensions of the topological version of Tverberg’s 1966 Theorem in the prime power case— and how the same method also was instrumental in the recent spectacular construction of counterexamples for the general