Molecular Scale Theoretical Studies of Energy Deposition and Redistribution in Crystalline High Explosives to Stimulate Enhanced Detectable Signatures

Theoretical studies of molecular scale near-field electron dynamics

The Journal of Chemical Physics ◽

10.1063/1.2335841 ◽

2006 ◽

Vol 125 (7) ◽

pp. 074709 ◽

Cited By ~ 8

Author(s):

Roi Baer ◽

Daniel Neuhauser

Keyword(s):

Near Field ◽

Theoretical Studies ◽

Electron Dynamics ◽

Field Electron ◽

Molecular Scale

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Nanolesions induced by heavy ions in human tissues: Experimental and theoretical studies

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.3.64 ◽

2012 ◽

Vol 3 ◽

pp. 556-563 ◽

Cited By ~ 5

Author(s):

Marcus Bleicher ◽

Lucas Burigo ◽

Marco Durante ◽

Maren Herrlitz ◽

Michael Krämer ◽

...

Keyword(s):

Heavy Ions ◽

Energy Deposition ◽

Biological Effects ◽

Biological Molecules ◽

Nanometer Scale ◽

Theoretical Studies ◽

Chromatin Conformation ◽

Human Tissues ◽

Kinetics Of ◽

Experimental And Theoretical Studies

The biological effects of energetic heavy ions are attracting increasing interest for their applications in cancer therapy and protection against space radiation. The cascade of events leading to cell death or late effects starts from stochastic energy deposition on the nanometer scale and the corresponding lesions in biological molecules, primarily DNA. We have developed experimental techniques to visualize DNA nanolesions induced by heavy ions. Nanolesions appear in cells as “streaks” which can be visualized by using different DNA repair markers. We have studied the kinetics of repair of these “streaks” also with respect to the chromatin conformation. Initial steps in the modeling of the energy deposition patterns at the micrometer and nanometer scale were made with MCHIT and TRAX models, respectively.

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STM of freeze-fracture replicas: Problems and promises

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100146187 ◽

1993 ◽

Vol 51 ◽

pp. 68-69

Author(s):

J. T. Woodward ◽

J. A. N. Zasadzinski

Keyword(s):

Scanning Tunneling Microscope ◽

Organic Materials ◽

Freeze Fracture ◽

Atomic Resolution ◽

Scanning Tunneling ◽

Tunneling Microscope ◽

Molecular Scale ◽

Organic Surfaces ◽

Metal Layers ◽

Conductive Surfaces

The Scanning Tunneling Microscope (STM) offers exciting new ways of imaging surfaces of biological or organic materials with resolution to the sub-molecular scale. Rigid, conductive surfaces can readily be imaged with the STM with atomic resolution. Unfortunately, organic surfaces are neither sufficiently conductive or rigid enough to be examined directly with the STM. At present, nonconductive surfaces can be examined in two ways: 1) Using the AFM, which measures the deflection of a weak spring as it is dragged across the surface, or 2) coating or replicating non-conductive surfaces with metal layers so as to make them conductive, then imaging with the STM. However, we have found that the conventional freeze-fracture technique, while extremely useful for imaging bulk organic materials with STM, must be modified considerably for optimal use in the STM.

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