The photosynthetic activity of marine phytoplankton from five algal classes (Phaeodactylum tricornutum, Skeletonema costatum, Thalassiosira oceanica, Thalassiosira weissflogii, Dunaliella tertiolecta, Mantoniella squamata, Emiliania huxleyi, Pavlova lutheri and Heterosigma akashiwo) was investigated under identical growth conditions to determine interspecies differences. Primary photochemistry ...

Excess irradiance can reduce the quantum yield of photosynthesis via photoprotective energy dissipation, inactivation or downregulation of PSII. We examined variation in photoprotection as part of a study of adaptive radiation in photosynthetic light responses byHawaiian lobeliads.Wemeasured themaximumefficiencyofPSII (Fv/Fm) and recoveryof Fv/Fm after high light stress in field populations of ...

The development of the photosystem II units in relation to the heterogeneity of their photochemical centers was studied in etiolated bean leaves (Phaseolus vulgaris var. red kidney) greened under continuous or intermittent light. The study was done in order to see whether grana are the loci of the units with the efficient photosystem II activity (alpha units), while the stroma thylakoids are th...

The organization and function of the photochemical apparatus of Synechococcus 6301 was investigated in cells grown under yellow and red light regimes. Broadband yellow illumination is absorbed preferentially by the phycobilisome (PBS) whereas red light is absorbed primarily by the chlorophyll (Chl) pigment beds. Since PBSs are associated exclusively with photosystem II (PSII) and most of the Ch...

Smirnovia iranica, a native valuable woody species from Fabaceae, is an adaptable plant of central sandy areas of Iran. Changes in chlorophyll fluorescence and photosynthetic pigments characteristics were analyzed in the course of phenological stages including vegetative, flowering, seed ripening, and seed falling stages, respectively (VS, FS, SRS, and SFS). The results obtained from analysis o...

With the present theoretical study of the photochemical switching of E-methylfurylfulgide we contribute an important step towards the understanding of the photochemical processes in furylfulgide-related molecules. We have carried out large-scale, full-dimensional direct semiempirical configuration-interaction surface-hopping dynamics of the photoinduced ring-closure reaction. Simulated static a...

OBJECTIVES In our investigations we have reported that photochemical reaction leading to brain ischemia can also be precipitated with visible light from a non-coherent light source. It was revealed that focal cerebral ischemia after photochemical reaction cause the alterations in the capillaries ultrastructure and perivascular spaces of the barrier-competent regions of the brain. The purpose of...

Photochemical activation of a deoxyribozyme with peroxidase activity was achieved by the synthesis and incorporation of a caged deoxyguanosine.

Herein we describe our efforts to elucidate the key mechanistic aspects of the previously reported enantioselective photochemical α-alkylation of aldehydes with electron-poor organic halides. The chemistry exploits the potential of chiral enamines, key organocatalytic intermediates in thermal asymmetric processes, to directly participate in the photoexcitation of substrates either by forming a ...

Photochemical Nitric oxide releasing composite materials (Photo-NORMs) were prepared using biocompatible polymers and the photochemical nitric oxide donor complex (CrONO). We have demonstrated nitric oxide (NO) release from the solid composites for extended (>30 hours) and controlled (20-100 pmoles s(-1)) durations after visible light irradiation. Quantitation of the efficiency of NO release fr...