[Le capitaine Charles A.] Smith commandant [le paquebot] Imperator CN [Central News Photo Service] New-York : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 58713

William Jennings Bryan CN [Central News Photo Service] New-York : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 58715

CN [Central News Photo Service] New-York, l'Imperator quittant Southampton : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 58716

Berlin, une cité de baraques [intérieur d'une maison], CN [cliché Central News photo service] USA : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 59494

Berlin, une cité de baraques, CN [cliché Central News photo service] USA : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 59495

Berlin, une cité de baraques, CN [cliché Central News photo service] USA : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 59496

Fête de Jeanne d'Arc à New-York, CN [cliché Central News photo service] USA : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 59497

Fête de Jeanne d'Arc à New-York, CN [cliché Central News photo service] USA : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 59498

Fête de Jeanne d'Arc à New York, CN [cliché Central News photo service] USA : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 59499

Photo Essay

Michael Snow's 'Photo Essay' that adorns a wall in A Block.

Photo-gravures of Niagara Falls. --

On cover: Niagara Falls.

Distribution of excitation energy in photosynthesis: a study of heat loss, photo chemical activity and fluorescence emission in intact calls of cyanobacterium.

Photosynthetic state transitions were investigated in the cyanobacterium Synechococcus sp. PCC 6301 by studying fluorescence emission, heat loss, and PS I activity in intact cells brought to state 1 and state 2. 77K fluorescence emission spectra were modelled with a sum of 6 components corresponding to PBS, PS II, and PS I emissions. The modelled data showed a large decrease in PS II fluorescence accompanied with a small increase in the PS I fluorescence upon transition to state 2 for excitation wavelengths absorbed by both PBS and ChI ll.. The fluorescence changes seen with ChI .a. excitations do not support the predictions of the mobile PBS model of state transition in PBS-containing organisms. Measurements of heat loss from intact cells in the two states were similar for both ChI it. and PBS excitations over three orders of magnitude of laser flash intensity. This suggests that the PBS does not become decoupled from PS II in state 2 as proposed by the PBS detachment model of state transition in PBS-containing organisms. PS I activity measurements done on intact cells showed no difference in the two states, in contrast with the predictions of all of the existing models of state transitions. Based on these results a model for state transition In PBScontaining organisms is proposed, with a PS II photoprotectory function.

Bell - Sloman Wedding Day Photo, 1939

This photograph was taken on the wedding day of Richard Nelson Bell and Iris Sloman in 1939. Pictured in the photograph, from left, are: Charles Bell, father of Richard Nelson Bell; Josephine Sloman, mother of Iris; Richard Nelson Bell; Iris Sloman Bell; Mary Bell, mother of Richard Nelson Bell; and Albert Sloman, father of Iris. This family photo was in the possession of Rick Bell, of St. Catharines, Ontario. The Sloman - Bell ancestry includes escaped Black slaves from the United States.