In this issue we welcome a new Problems Editor, David Angell.
Detection of the arrival of important proteins at the cell surface is a problem of intense biological interest. Here we create an ideal model of the arrival of proteins at the cell membrane, as seen by a total internal reflection fluorescence microscope.
I'm no math genius. Mr Boxold always said math is about thinking up new ways of looking at things, even old problems. That's all I did.
Some years ago, in response to an altogether unusual number of reader requests, I wrote a column on the work of a woman usually called Ada Lovelace.
Q1341 A lazy weather forecaster predicts that future maximum temperatures will be the average of the preceding two days maximum temperatures. The forecaster starts his forec
Q1331 Given any positive integers $m$ and $n$ prove that every divisor of $mn$ can be expressed as a product of a divisor of $m$ and a divisor of $n$.