A PHOTOELECTRIC DENSITOMETER FOR USE WITH SUSPENSIONS

A Photoelectric Densitometer for Use with Suspensions

A device for quickly and accurately measuring the population density of a suspension of microorganisms, permitting the preparation of yeast suspensions of known density to within 1 per cent error, was constructed with two Visitron photoelectric cells, a single light of high intensity and a good Wheatstone bridge for balancing the currents from the two photoelectric cells. A large Pyrex milk cul...

A photoelectric ear densitometer for continuously recording the arterial concentration of T-1824 in the dye-dilution method.

To eliminate the collection of serial samples of arterial blood an instrument has been developed which records dye-dilution curves by measuring changes in optical density of a segment of a heatflushed ear. Comparison with curves from arterial samples shows close similarity in the shape of the curves, and good agreement between the cardiac outputs calculated from them. Other advantages of the te...

A densitometer for quantitative autoradiography.

A low cost spot densitometer system is described. This system is useful for quantitative autoradiography of local cerebral glucose utilization, blood flow, receptor binding and other applications requiring densitometry on films. The densitometer can be used alone or interfaced to a microcomputer. The densitometer consists of a photographic enlarger, a digital multimeter, and the densitometer el...

Use and application of the cuvette densitometer as an oximeter.

A simple method for screening photoelectric dyes towards their use for retinal prostheses.

Photoelectric dyes absorb light and convert photon energy to electric potentials. To test whether these dyes could be used for retinal prostheses, a simple in vitro screening system was developed. Retinal neurons were cultured from the eyes of chick embryos at the 10-day embryonic stage, at which time no retinal photoreceptor cells have yet developed. Intracellular calcium elevation was observe...