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High CMRR Instrumentation Amplifier (Schematic and Layout) design for biomedical applications

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Instrumentation amplifiers are intended to be used whenever acquisition of a useful signal is difficult. IA’s must have extremely high input impedances because source impedances may be high and/or unbalanced. bias and offset currents are low and relatively stable so that the source impedance need not be constant. Balanced differential inputs are provided so that the signal source may be referenced to any reasonable level independent of the IA output load reference. Common mode rejection, a measure of input balance, is very high so that noise pickup and ground drops, characteristic of remote sensor applications, are minimized.Care is taken to provide high, well characterized stability of critical parameters under varying conditions, such as changing temperatures and supply voltages. Finally, all components that are critical to the performance of the IA are internal to the device. The precision of an IA is provided at the expense of flexibility. By committing to the one specific task of
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New MRI Dye Enables Drastically Higher Resolution 3D Images of Living Brain

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In a breakthrough that can drastically increase the resolution and detail of magnetic resonance imaging, a fluorescent dye that enables high-resolution (about 1 micron) 3D images of the cerebral vascular system has been synthesized by researchers at the Laboratoire de Chimie (CNRS) in France.
In collaboration with the Institut des Neurosciences of the Université Joseph Fourier in Grenoble, France, the researchers developed the "Lem-PHEA chromophore" dye that exhibits exceptionally high fluorescence in the near-infrared region of the biological transparency window and can also pass through the skin. It features solubility in biological media, low cost, non-toxicity, and full elimination by the kidneys, suggesting that it may be suitable for in vivo imaging, the researchers say.

By injecting the dye into the blood vessels of a mouse, the scientists could reveal details of the rodent's vascular system with previously unattainable precision -- compared to current dyes (such as Rhodamine-B and cyanine derivatives), and to conventional MRI medical imaging, which is limited to resolution of a few millimeters -- increasing the resolution by a factor of 1000.