Abstract: Provided is a compound having the structure: (SIG)-(SI-MOD)m where SIG is a signaling molecule, SI is a self-immolative structure bound to SIG such that SIG has a reduced signal relative to the signal of SIG without SI, MOD is a moiety bound to SI that is subject to modification by an activator, and m is an integer from 1 to about 10. When MOD is modified by an activator, SI is destabilized and self-cleaved from SIG such that SIG generates an increased signal. Also provided are methods of determining whether a sample, such as a cell, comprises an activator, such as a nitroreducase, using the compound. Further provided are methods of determining whether a mammalian cell is hypoxic using the compound where nitroreductase is the activator. A method of detecting a microorganism that comprises a nitroreductase using the compound where nitroreductase is the activator is also provided.

Abstract: In one embodiment, an image developer includes a developer roller rotatable along a photoconductor for presenting a layer of ink to the photoconductor and a cleaner for cleaning ink from the developer roller. The cleaner includes a first cleaning roller rotatable along the developer roller for removing ink from the developer roller and a second cleaning roller rotatable against the first cleaning roller for mechanically removing ink from the first cleaning roller. In one embodiment, the second cleaning roller deforms against the first cleaning roller such that the cross-sectional length of contact between the first and second cleaning rollers is in the range of 20% to 38% of the circumference of the first cleaning roller. In one embodiment, the second cleaning roller has a density in the range of 90 kg/m3 to 150 kg/m3.

Abstract: In one embodiment, an image developer includes a developer roller rotatable along a photoconductor for presenting a layer of ink to the photoconductor and a cleaner for cleaning ink from the developer roller. The cleaner includes a first cleaning roller rotatable along the developer roller for removing ink from the developer roller and a second cleaning roller rotatable against the first cleaning roller for mechanically removing ink from the first cleaning roller. In one embodiment, the second cleaning roller deforms against the first cleaning roller such that the cross-sectional length of contact between the first and second cleaning rollers is in the range of 20% to 38% of the circumference of the first cleaning roller. In one embodiment, the second cleaning roller has a density in the range of 90 kg/m3 to 150 kg/m3.