Electron beam irradiation for structuring of molecular assemblies

Nontraditional applications of electron beam irradiation for patterning of molecular assemblies are considered. The electron beam can have the following effects on molecular layers: destruction of molecular structure under e-beam irradiation with a successive formation of new molecular system when the irradiation is stopped; variation of the properties of the layer after e-beam irradiation; crosslinking of molecules in the layer under irradiation; modification of the templates for the successive film growth, providing different growing conditions in irradiated and nonirradiated areas; and activation of the solid support surface and molecular systems in the film resulting in the increased adhesion of the layer to the substrate in irradiated areas. All these effects were used for patterning of thin layers of different compounds. Five classes of molecular systems were considered, namely, films of simple surfactant molecules, layers of charge-transfer complexes, films of conducting polymers, aggregated nanoparticulate layers and films of nanoengineered polymeric capsules. Characteristic features of patterning processes in each particular case are discussed.     

Oriented purple membrane multilayers of halobacteria fabricated by langmuir–blodgett and electrophoretic sedimentation techniques

Organised films containing oriented patches of purple membranes and consisting of 15–75 layers and approximately 1000 layers were fabricated by the Langmuir–Blodgett and electrophoretic sedimentation techniques respectively. ‘Surface pressure vs. molecular area’ isotherms for monolayers of purple membranes suspended in hexane and deposited on the air/water interface were studied. Circular dichroism and absorption spectroscopy were used to investigate the effect of an organic solvent on the chromophore binding site in the purple membranes. Kinetic methods based on flash excitation were employed to determine the influence of the film deposition conditions on the photoelectric response of bacteriorhodopsin and on the M₄₁₂ intermediate relaxation. Structural characteristics for multilayers prepared from water and hexane purple membrane suspensions were determined by low-angle X-ray scattering. The influence of the layer deposition conditions on the electrical, physical and photoelectrical properties of ordered structures containing bacteriorhodopsin is discussed.     

The pathoanatomical,diagnosis of progressive forms of pulmonary tuberculosis in relation to the new clinical classification

This communication is a letter of information that gives for postmortem diagnosis a brief account of tuberculous inflammation and major types of pulmonary tuberculosis during their progression to death and an approximate outline of pathoanatomical diagnosis. Terminal tuberculosis is shown to be now complicated by miliary and caseous pneumonias. Caseous pneumonia may appear as an independent nosological entity and as a complication of acute progression, more frequently, of fibrocavernous tuberculosis. Caseous pneumonia as a tuberculosis type is an irreversible process that calls for emergency surgical treatment. It has been found that there are primarily impairments in lung connective tissue function, acute mesenchymopathy with high blood barrier permeability in caseous pneumonia. Terminal bronchiolar lesion is a later stage in the pathogenesis of caseous pneumonia.