The mechanism of photoactivation of photosystem I electron transport was studied in intact Bryopsis corticulans chloroplasts. The evidence from chemical and photochemical studies suggests that photoactivation is a consequence of a reduction of an electron transport component, presumably ferredoxin-NADP(+) reductase. O(2) does not act as a mediator of the process but rather acts as an electron a...

Photosynthetic electron transport is coupled to ATP synthesis. This process - photosynthetic phosphorylation - proceeds by several alternative electron-transport pathways in isolated chloroplasts. The question: 'Which of these works in real life?' has long occupied students of photosynthesis. Recent results from structural biology and genomics suggest that the answer is 'All of them'. The inter...

Fragments of bundle sheath strands, free of mesophyll cells and showing a chlorophyll a/b ratio of 6.0 to 6.6 were prepared from Zea mays by a mechanical method. They were unable to photoreduce ferricyanide but were able to photoreduce the membrane-permeant 2,5-dimethylquinone at a rate of 250 to 420 microequivalents per hour per mg chlorophyll (mueq/hr . mg Chl) at 21 C. In the presence of the...

this paper is a computational study of the behavior of aerodynamics  characteristics of an airfoil with blunt trailing edge and  studies the effects aerodynamic performance caused by modifications made to the trailing edge. blunt trailing edge airfoils are of interest in the engineering of large wind turbine blades because they allow for a strong structure with a high aerodynamic lift to struct...

We propose in this note the study of quantum channels from association schemes. This is done by interpreting the (0, 1)-matrices of a scheme as the Kraus operators of a channel. Working in the framework of one-shot zero-error information theory, we give bounds and closed formulas for various independence numbers of the relative non-commutative (confusability) graphs, or, equivalently, graphical...

The role of chloride in photosynthetic oxygen evolution was reinvestigated by determining the effect of this ion on photochemical reactions of chloroplasts in which oxygen either is or is not produced. The chloroplasts used were isolated from normal spinach leaves. The level of chloride in the reaction mixture was controlled by washing the isolated chloroplasts and by avoiding a chloride contam...