Scanning Magnetic Microscope Using a Gradiometric Configuration for Characterization of Rock Samples.

Scanning magnetic microscopy is a tool that has been used to map magnetic fields with good spatial resolution and field sensitivity. This technology has great advantages over other instruments; for example, its operation does not require cryogenic technology, which reduces its operational cost and complexity. Here, we presented a spatial domain technique based on an equivalent layer approach for processing the data set produced by magnetic microscopy.

Discrete cutaneous lesions in a critically ill patient treated only for AIDS and miliary tuberculosis: a case report of disseminated histoplasmosis.

Histoplasmosis is a systemic mycosis caused by the dimorphic fungus Histoplasma capsulatum, with disseminated histoplasmosis (HD) being one of its clinical forms. As a consequence of the HIV-AIDS pandemic, HD has become prevalent not only in regions that are recognized as endemic but also in areas not considered endemic, such as Europe and Asia. Its clinical manifestations are varied and mimic several infectious diseases, mainly tuberculosis.

Characterizing Complex Mineral Structures in Thin Sections of Geological Samples with a Scanning Hall Effect Microscope.

We improved a magnetic scanning microscope for measuring the magnetic properties of minerals in thin sections of geological samples at submillimeter scales. The microscope is comprised of a 200 µm diameter Hall sensor that is located at a distance of 142 µm from the sample; an electromagnet capable of applying up to 500 mT DC magnetic fields to the sample over a 40 mm diameter region; a second Hall sensor arranged in a gradiometric configuration to cancel the background signal applied by the electromagnet and reduce the overall noise in the system; a custom-designed electronics system to bias the sensors and allow adjustments to the background signal cancelation; and a scanning XY stage with micrometer resolution. Our system achieves a spatial resolution of 200 µm with a noise at 6.