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This paper is dedicated to atomic force microscopy (AFM) as a progressive tool for imaging bacterial surfaces and probing their properties. The description of the technique is complemented by the explanation of the method's artifacts typical, in particular, for the imaging of bacterial cells. Sample preparation techniques are summarized in a separate section. Special attention is paid to the differences in imaging of gram-positive and gram-negative bacteria. Probing of mechanical properties, including elastic modulus, fragility, and adhesion of the cell walls is emphasized. The advantages of AFM in the studies of real-time cellular dynamical processes are illustrated by the experiment with the germination of spores.

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A new microscopic procedure for the visualization of structural rearrangements in amorphous polymers during their deformation to high strains is described. This approach involves the deposition of thin (several nanometers) metallic coatings onto the surface of the deformed polymer. Subsequent deformation entails the formation of a relief in the deposited coating that can be studied by direct microscopic methods. The above phenomenon of relief formation provides information concerning the deformation mechanism of the polymer support. Experimental data obtained with the use of this procedure are reported, and this evidence allows analysis of the specific features of structural rearrangements during deformation of the amorphous polymer at temperatures above and below its glass transition temperature under the conditions of plane compression and stretching, uniaxial tensile drawing and shrinkage, rolling, and environmental crazing. This direct structural approach originally justified in the works by Academician V.A. Kargin appears to be highly efficient for the study of amorphous polymer systems.

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Structural rearrangements during the temperature-induced shrinkage of amorphous polycarbonate after its tensile drawing below and above the glass transition temperature, rolling at room temperature, and solvent crazing have been studied with the use of the direct microscopic procedure. This evidence demonstrates that the character of structural rearrangements during the temperature-induced shrinkage of the oriented amorphous polymer is primarily controlled by the temperature and mode of deformation. In the case of the polymer sample stretched above the glass transition temperature, the subsequent temperature-induced shrinkage is shown to be homogeneous and proceeds via the simultaneous diffusion of polymer chains within the whole volume of the polymer sample. When polymer deformation is carried out at temperatures below the glass transition temperature, the subsequent temperature-induced shrinkage within the volume of the polymer sample is inhomogeneous and proceeds via the movement of rather large polymer blocks that are separated by the regions of inelastically deformed polymer (shear bands or crazes).