RESUMO
We present a Green's-function/Green's-theorem integral equation approach to numerically modeling two-dimensional, s-polarized, wave propagation problems effectively for a variety of geometries. The model accurately calculates both near fields and far fields because of the minimal assumptions made on the behavior of the scattered radiation. The method was applied to modeling light emission from a near-field scanning optical microscope fiber tip. Several convergence and energy tests were used to give confidence in the results. The behavior of intensity and power near the tip was investigated. The effects of changing the dielectric constant of a sample material located below the tip were also examined.
RESUMO
Three media for human semen were tested--(1) HAMS F10 supplemented with fructose, glycine and glycerol (MHAMS), (2) another chemically defined medium, but specifically designed for human semen (HSPM) and (3) medium containing egg yolk (EYCM). Twenty ejaculates of donor quality were divided into three aliquots, each aliquot was mixed with a different medium, the solutions were vapour frozen, and stored at -196 degrees C. Motility and quality of motility were measured 0.5 h and 3 h after thawing. Average cryosurvivals 0.5 h after thawing for MHAMS, HSPM and EYCM were 44.1 (s.d. = 17.0)%, 56.0 (s.d. = 15.3)% and 66.0 (s.d. = 10.8)%, respectively; the proportions of ejaculates with cryosurvival below 50% were 11/20, 5/20 and 1/20 respectively. The results indicated that the EYCM medium had clear advantages over other cryoprotective solutions for use in a spermatozoa freezing programme.
