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Uptake of cytotoxic drugs by typical tumor cells is limited by the dense dendritic network of oligosaccharide mucin chains that forms a mechanical barrier. Atomic force microscopy is used to directly measure the force needed to pierce the mucin layer to reach the cell surface. Measurements are analyzed by de Gennes’ steric reptation theory. Multidrug resistant ovarian tumor cells shows significantly larger penetration load compared to the wide type. A pool of pancreatic, lung, colorectal, and breast cells are also characterized. The chemotherapeutic agent, benzyl-α-GalNac, for inhibiting glycosylation is shown to be effective in reducing the mechanical barrier.

Achieving a high degree of radiation symmetry is a critical feature of target designs for indirect-drive inertial confinement fusion. Typically, the radiation flux incident on the capsule is required to be uniform to 1% or better. It is generally possible to design a hohlraum that provides low values of higher-order asymmetry (Legendre mode P10 and above) due to geometric averaging effects. Because low-order intrinsic asymmetry (e.g., Legendre modes P2 and P4) are less strongly reduced by geometric averaging alone, the development of innovative control techniques has been an active area of research in the inertial fusion community over the years. Shields placed inside the hohlraum are one example of a technique that has often been proposed and incorporated into hohlraum target designs. Simple mathematical considerations are presented indicating that radiation shields may be designed to specifically tune lower-order modes (e.g., P4) without deleterious effects on the higher order modes. Two-dimensional vie...

The metastable, ferromagnetic, tetragonal phase in the Mn-Al system has been obtained by isothermal transformation of a high-temperature phase. Transmission electron micrographs of specimens of this phase so obtained (bulk iHc = 1130 oe) show striations of light (transmitting) and dark (non-transmitting) material. The striations are presumed to arise from stresses induced by the transformation and/or cooling. Transmission electron diffractograms contain individual patterns both with and without superlattice reflections. Respective patterns reveal axial ratios of 0.90 and 0.94, and are correlated with the dark and light areas of the micrographs. From diffraction data it is concluded that the trace of the boundary between the light and dark regions coincides with a projection of the c axis. The possibility of coherency as a mechanism for the high coercive force, analogous to CoPt, is discussed. The type of cooperative atomic interaction as related to the shift in the axial ratio is also discussed.