The genesis of lasing, as an evolution the laser hybrid eigenstates comprised electromagnetic modes and atomic polarization, is considered. It shown that start coherent generation at threshold preceded by formation a special state lasing prethreshold. This characterized enhanced coupling among excited atoms modes. leads to increase in rate stimulated emission and, ultimately, lasing. At prethre...

objectives: microleakage is the main concern in composite restorations. this study aimed to compare the microleakage of two bulk-fill and one conventional composite at two different time points. methods: class ii cavities were prepared in 60 premolar teeth and divided into six groups of 20. groups 1 and 4 were incrementally filled with grandio composite. groups 2 and 5 were filled with x-tra fi...

Abstract We extend classical ideal point estimation to allow voters have different preferences when voting in domains—for example, on agricultural policy than defense policy. Our scaling procedure results estimated points a common scale. As result, we are able directly compare member’s revealed across domains of (different sets motions) assess if, for member votes more conservatively agricultur...