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Using the closed F g → F e = F g +1 D2 line transition of Rb atoms, we report experimental and numerical evidence of influence of additional transverse magnetic field when examining electromagnetically induced absorption ͑EIA͒ in the Hanle configuration. The effect was analyzed with two directions of additional magnetic field and in the cases of excitation with linear, elliptical, and circular laser light polarization. The transverse magnetic field brings substantial differences in the resonance line shape, amplitude, and width. Our theoretical model includes Doppler broadening. Numerical solutions of our theoretical model are in good agreement with experimental results. This analysis points out the importance of the presence of stray magnetic fields when studying EIA.

Indoor radon measurements by nuclear track detectors and application of the method in secondary schools in Serbia were performed in the spring 2004. Thirty detectors (type CR-39) were distributed to high school teachers in several cities in Serbia. After three months of the detectors exposure, they were sent back to the Low- Level Laboratory, Institute of Physics, Belgrade. After exposure, the CR-39 detectors were etched in a 6N NaOH at 700C for 3 hours. The tracks were counted by the semiautomatic track-counting system. The preliminary results are presented in this paper

Patterns of electroencephalographic (EEG) and polygraphically recorded cardiovascular (CV) reactivity to the glare pressor test (GPT) were compared in 19 healthy, young male professional drivers and eight non-driver controls. After the first headlight impulse, 15 drivers showed persistent blockade of spontaneous alpha activity or complete desynchronization. This was accompanied by a significant fall in digital pulse amplitude and a significant rise in diastolic blood pressure (BP) (7.3 +/- 9.5 mmHg). Most drivers recovered baseline alpha activity and showed milder diastolic BP and digital pulse changes after the final (5th) glare impulse. However, in two drivers this last glare stimulus elicited the most pronounced changes: in one case a rapid onset of ventricular extrasystoles and in the other, maximal rise in diastolic BP, together with a persistently desynchronized EEG. No significant effects of the GPT upon central and CV indices were found in the control group. These results indicate that drivers show cardiovascular hyperreactivity to the GPT, with strong central arousal as expected during night driving when an on-coming headlight can represent impending danger and the need for accurate and timely responses to avoid a collision. Once optimal stimulus parameters for routine application are determined, the glare pressor test with EEG and polygraphic recording will offer a clinically useful, standardizable method for evaluating the connection between central mechanisms and CV reactivity in professional drivers, a cohort of patients whose occupational activity epitomizes mentally stressful work, and who are at high cardiac risk.

We describe a real-time holographic technique used to observe dental contraction due to photo-polymerization of dental filling during LED lamp illumination. An off-axis setup was used, with wet in-situ processing of the holographic plate, and consequent recording of interference fringes using CCD camera. Finite elements method was used to calculate internal stress of dental tissue, corresponding to experimentally measured deformation. A technique enables selection of preferred illumination method with reduced polymerization contraction. As a consequence, durability of dental filling might be significantly improved.