Many photosynthetic organisms use state transitions to rapidly balance light absorption by photosystems I and II (PSI and PSII) under varying light conditions (see Lemeille and Rochaix, 2010). During state transitions in plants, a major antenna complex in thylakoid membranes, light-harvesting complex II (LHCII), migrates between the two photosystems. Under State II conditions, when PSII is pref...

New stable decagonal quasicrystal in the system Al–Ir–Os S. Katrych a, Th. Weber a, M. Kobas b, L. Massüger a, L. Palatinus c,1, G. Chapuis c, W. Steurer a,∗ a Laboratory of Crystallography, Department of Materials, ETH Zurich, Wolfgang-Pauli-Strasse 10, 8093 Zurich, Switzerland b SLS Detector Group, Swiss Light Source, Paul-Scherrer-Institut, CH-5232 Villigen-PSI, Switzerland c Laboratory of C...

let $g$ be a finite group‎. ‎we denote by $psi(g)$ the integer $sum_{gin g}o(g)$‎, ‎where $o(g)$ denotes the order of $g in g$‎. ‎here we show that‎ ‎$psi(a_5)< psi(g)$ for every non-simple group $g$ of order $60$‎, ‎where $a_5$ is the alternating group of degree $5$‎. ‎also we prove that $psi(psl(2,7))

Oxygenic photosynthesis supports virtually all life forms on earth. Light energy is converted by two photosystems-photosystem I (PSI) and photosystem II (PSII). Globally, nearly 50% of photosynthesis takes place in the Ocean, where single cell cyanobacteria and algae reside together with their viruses. An operon encoding PSI was identified in cyanobacterial marine viruses. We generated a PSI th...

Water deficits during seed filling often decrease seed size in soybean (Glycine max L.). The physiological basis for this response is not known but may result from direct effects of low seed water potential (Psi(w)) on the seed filling process. To determine whether low Psi(w) occurred in reproductive tissues of soybean, we monitored the water status (Psi(w), Psi(s), and Psi(p)) of leaf, pericar...

Data are presented which suggest the existence of a light-harvesting pigment-protein complex which is functionally and structurally associated with photosystem I (PSI) reaction centers. These observations are based on techniques which allow isolation of PSI using minimal concentrations of Triton X-100. Properties of density and self aggregation allowed purification of a "native" PSI complex.The...

Predawn plant water potential (Psi(w)) is used to estimate soil moisture available to plants because plants are expected to equilibrate with the root-zone Psi(w). Although this equilibrium assumption provides the basis for interpreting many physiological and ecological parameters, much work suggests predawn plant Psi(w) is often more negative than root-zone soil Psi(w). For many halophytes even...

Photosystem I (PSI) photoinhibition suppresses plant photosynthesis and growth. However, the mechanism underlying PSI photoinhibition has not been fully clarified. In this study, in order to investigate the mechanism of PSI photoinhibition in higher plants, we applied repetitive short-pulse (rSP) illumination, which causes PSI-specific photoinhibition in chloroplasts isolated from spinach leave...