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A warm body emits radiation whose intensity I is dependent on the surface temperature T. For T near room temperature this radiation is mostly in the mid-IR. Radiometric measurement of I is often used for non contact thermometry. Temperature measurements in situ and in remote locations can be carried out using optical fibers, but one needs fibers that are highly transparent in the mid-IR. Our group has developed fibers made of silver halides. These are flexible, nontoxic, not hygroscopic and highly transparent in the mid IR. These fibers served for the development of a novel fiberoptic radiometer. Using this radiometer we have measured the temperatures of samples while being imaged in an MRI system. The presence of the fibers inside the MRI system did not interfere with the operation of the MRI nor did not the MRI system affect the radiometer. The temperature measurements were made with accuracy of 0.3°C, response time of 1 s and spatial resolution of 1 mm. Fiberoptic radiometers would be highly suitable for temperature measurement of human tissues, for example during surgical procedures done inside an MRI system.

As part of a project to construct virus-resistant transgenic grapevines, grapevine virus A (GVA) coat protein (CP) sequences were introduced into grapevine and the model plantNicotiana benthamiana.The engineered constructs were tested for their ability to engender resistance inN. benthamiana.A number of GVA-CP-transformedN. benthamianalines have become resistant to GVA. Preliminary biological and molecular analyses strongly suggest that in most cases the obtained resistance is RNA-mediated. Several lines of transgenic grapevine were obtained.