For Once

Once and only once.

V enous thrombosis is a fairly common disorder that manifests mainly as deep vein thrombosis of the leg or pulmonary embolism. It affects 1 in 1000 individuals annually and has a substantial mortality rate. 1 Its causes are both genetic (prothrombotic abnormalities sometimes referred to as a group as thrombophilia) and acquired. 2 Among the latter are cancer, female hormone use, and all forms o...

For once then, something...

My third year of medical school, and I have finally begun my training. I am slowly learning to be a surgeon. I will open you up and search through the detritus of sickness, extirpate what is necessary, and leave in my wake a health of my own creation. There is power in that; a power that I have already glimpsed. Reaching out and calmly saying, "knife." Deliberately moving the scalpel across the...

Once and For All

It has long been known that past-time operators add no expressive power to linear temporal logics. In this paper, we consider the extension of branching temporal logics with past-time operators. Two possible views regarding the nature of past in a branching-time model induce two different such extensions. In the first view, past is branching and each moment in time may have several possible fut...

once daily combination regimen for hiv infection

DNA Replication: Once, and only once

The preparation for DNA replication initiation is tightly linked to cell-cycle progression, ensuring that replication occurs only once per cycle. The time is ripe for a molecular dissection of the links between the two processes.