55 research outputs found
Image and Coherence Transfer in the Stimulated Down-conversion Process
The intensity transverse profile of the light produced in the process of
stimulated down-conversion is derived. A quantum-mechanical treatment is used.
We show that the angular spectrum of the pump laser can be transferred to the
stimulated down-converted beam, so that images can also be transferred from the
pump to the down-converted beam. We also show that the transfer can occur from
the stimulating beam to the down-converted one. Finally, we study the process
of diffraction through an arbitrarily shaped screen. For the special case of a
double-slit, the interference pattern is explicitly obtained. The visibility
for the spontaneous emitted light is in accordance with the van Cittert -
Zernike theorem for incoherent light, while the visibility for the stimulated
emitted light is unity. The overall visibility is in accordance with previous
experimental results
Estabilidade e adaptabilidade do algodoeiro herbáceo no Cerrado do Mato Grosso e Mato Grosso do Sul
Metabolic Consequences of Expression of the Medium Chain Hydrolase Gene of the Rat in Mouse NIH 3T3 Cells
Carnitine, apelin and resveratrol regulate mitochondrial quality control (QC) related proteins and ameliorate acute kidney injury: role of hydrogen peroxide
Follicular dendritic cells in lymph nodes after x-irradiation.
Follicular dendritic cells (FDC), non lymphoid cells present in lymph follicles, are characterized by numerous cytoplasmic processes retaining antigen-antibody complexes. Their origin, nature and function are unknown. Mice inguinal lymph nodes after 4.5 or 7.5 Gy X-irradiation were depleted of lymphoid cells. Ultrastructural observations during the first few days post-irradiation show that FDC are unaltered and possess dendritic processes enveloping dense material. Furthermore, they show intense metabolic activity. A lamina densa, never observed so well-developed in other lymph node cells, was detected around the nuclear envelope. The localization of junctions between FDC was analysed. FDC preserve their typical cytoplasmic processes even if lymphoid cells are rare. The latter thus seem not to be responsible for the maintenance of FDC integrity or their development. The possible role of this for antibody production is discussed. Irradiated lymph nodes of lymphoid cells are highly convenient for studying FDC. Isolation of FDC from irradiated lymph organs would seem to be possible
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