Quantitative Detection of Superoxide Ions in Whole Blood of the American Alligator (Alligator mississippiensis)

WST-1 and nitroblue tetrazolium (NBT) were used to quantify production of superoxide ions by leukocytes of the American alligator in whole blood. Because of the difficulty of isolating healthy leukocytes in alligators, these compounds were employed in whole blood instead of leukocyte preparations commonly used in other studies. The detection of superoxide was concentration- and time-dependent and linear with serial dilutions of whole blood. WST-1 reduction was inhibited by superoxide dismutase, indicating that the reduction was due to the presence of superoxide. Light microscopy revealed that superoxide production occurred in leukocytes, with no detectable contributions from other blood components.     

Dissymetry of critical exponants in YBCO

We report on measurements of the specific heat of μg-size YBCO single crystals very close to the superconducting transition in zero field. Detailed data points are obtained down to reduced temperatures of 10^?5. Analysis of the derivative of the specific heat yields the critical exponents in an unambiguous way. α+ is positive ～0.5; α- is negative ～ ?0.3. The value of α+ is consistent with gaussian fluctuations above Tc, however the value of α- is inconsistent with either gaussian fluctuations or the 3DXY model.     

Stationary solutions of plane nonlinear optical antiwaveguides

Eigenvalues and eigenfunctions of stationary TE waves for plane symmetrical nonlinear waveguides are studied. For a negative refractive index difference between the core and cladding (antiwaveguide) regions are found where a continuum of eigenfunctions exist in certain energy intervals. Such regions are interpreted as regions of stability. There is possible concentration of optical power in the core as well as in the cladding in these regions. Boundary values of propagation constants for nonlinear waveguides and antiwaveguides are obtained.     

Grid attenuators in laser machining systems

General equations for the attenuated and focused intensity distribution of a gaussian beam at the focal region are derived for two-dimensional arbitrary shaped grid attenuators. Assuming a circular aperture grid, calculations of the intensity distribution in the focal plane and at several planes of the focal region were done. Results of calculations and relevant experiments are reported and discussed, in view of the application of these types of attenuators in laser machining systems.