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Record 1,  Textual support,  English

Record number: 1, Textual support number: 1 CONT

STED [stimulated emission depletion] microscopy was the first high-resolution microscopy concept applied more widely for the study of biological questions. As performed in classical confocal laser scanning microscopy, a conventional laser beam is used to stimulate the fluorescent molecules in what is a normal excited spot (of several hundred nanometers in diameter). A second toroidal (doughnut shaped) beam is used to quench the fluorophores by stimulated emission. By overlapping the two beams, fluorescence is allowed only from the center of the spot, which thus generates a much smaller exciting focal spot ... Thus, in practical terms, a smaller effective PSF [point spread function] is generated that causes less blurring and, therefore, results in higher resolution. Theoretically, the gain in resolution is not physically limited: it only depends on the power of the quenching laser beam (the higher the power, the smaller the imaging spot becomes).  1, record 1, English, - quenching%20laser%20beam

Record 1,  Textual support,  French

Record number: 1, Textual support number: 1 CONT

Microscopie de fluorescence à déplétion par émission stimulée (STED) - [On utilise] un microscope de fluorescence à balayage où on superpose au faisceau d’excitation classiquement présent, un faisceau de déplétion mis en forme de doughnut afin de dépasser la limite de résolution imposée par la diffraction. Cette limite est dépassée en utilisant l'émission stimulée pour empêcher l’émission de fluorescence dans la zone associée au doughnut. Ainsi seule la zone intérieure au doughnut peut encore émettre de la fluorescence, et la largeur de cette zone centrale est ajustée grâce à la saturation des effets de déplétion de la fluorescence.  2, record 1, French, - laser%20de%20d%C3%A9pl%C3%A9tion

Record number: 1, Textual support number: 1 OBS

Le «quenching» correspond à une relaxation non-radiative des électrons excités vers l’état fondamental. Le RET (transfert d’énergie par résonance) est une forme de «quenching».  1, record 1, French, - laser%20de%20d%C3%A9pl%C3%A9tion

Record 1,  Textual support,  Spanish