The current status of sensors capable of continuous measurement of analytes in biological media is reviewed. This review containing 173 references deals with devices whose use in single cells, tissue ...slices, animal models and humans has been demonstrated. In addition to sensors specific for glucose, lactate, glutamate, pyruvate, choline and acetylcholine, insights obtained from monitoring nitric oxide, Na
+, K
+, Ca
2+, and dopamine are presented. Performance criteria for sensor performance are described as is the subject of biosensor calibration. Biocompatibility issues are dealt with in some detail as is the status of continuous blood glucose monitoring in humans.
The Spitzer Extended Deep Survey (SEDS) is a very deep infrared survey within five well-known extragalactic science fields: the UKIDSS Ultra-Deep Survey, the Extended Chandra Deep Field South, ...COSMOS, the Hubble Deep Field North, and the Extended Groth Strip. SEDS covers a total area of 1.46 deg super(2) to a depth of 26 AB mag (3sigma) in both of the warm Infrared Array Camera (IRAC) bands at 3.6 and 4.5 mum. Because of its uniform depth of coverage in so many widely-separated fields, SEDS is subject to roughly 25% smaller errors due to cosmic variance than a single-field survey of the same size. SEDS was designed to detect and characterize galaxies from intermediate to high redshifts (z = 2-7) with a built-in means of assessing the impact of cosmic variance on the individual fields. Because the full SEDS depth was accumulated in at least three separate visits to each field, typically with six-month intervals between visits, SEDS also furnishes an opportunity to assess the infrared variability of faint objects. This paper describes the SEDS survey design, processing, and publicly-available data products. Deep IRAC counts for the more than 300,000 galaxies detected by SEDS are consistent with models based on known galaxy populations. Discrete IRAC sources contribute 5.6 + or - 1.0 and 4.4 + or - 0.8 nW m super(-2) sr super(-1) at 3.6 and 4.5 mum to the diffuse cosmic infrared background (CIB). IRAC sources cannot contribute more than half of the total CIB flux estimated from DIRBE data. Barring an unexpected error in the DIRBE flux estimates, half the CIB flux must therefore come from a diffuse component.