Oxygenminimum zones (OMZs) are often characterized by nitrogen-to-phosphorus (N:P) ratios far lower than the canonical Redfield ratio. Whereas, the importance of variable stoichiometry in phytoplankton has long been recognized, variations in zooplankton stoichiometry have received much less attention. Here we combine observations from two shipboard mesocosm nutrient enrichment experiments with ...

Glutamate is a major excitatory neurotransmitter in the vertebrate brain. AMPA-type glutamate receptors mediate fast excitatory transmission. AMPA receptors assemble with transmembrane AMPA receptor regulatory protein (TARP) auxiliary subunits and function as native ion channels. However, the assembly and stoichiometry of AMPA receptor and TARP complexes remain unclear. Here, we developed a nov...

We report on the crystal structure of urea (U) with acetic acid (A), its physical stability and its predictability using computational methods. The crystal structure of urea:acetic acid (U:A) shows hydrogen-bond ribbons and a 1:2 stoichiometry. Crystal structure prediction calculations are presented for two sets of U:A stoichiometries: 1:1 and 1:2. A 1:3 stoichiometry is also partially explored...

The P/2eratio of noncyclic photophosphorylation was investigated in the light of recent reports that it is greater than one and may reflect the existence of two types of electron transport, a phosphorylating and a nonphosphorylating type, superimposed on each other. Our results, obtained under experimental conditions that included those reported to be conducive to high ratios, are consistent wi...

The complexation reaction between salen (Bis(salicylidene)ethylenediamine) and Cu(II) cations in methanol (MeOH), 2-propanol (2-PrOH), acetonitrile (AN), tetrahydrofuran (THF), and chloroform (CHCl3) as nonaqueous solvents at 25º C has been investigated. The stoichiometry and formation constants of complexes have been determined spectrophotometrically and conductometrically by method of continu...

By using an elemental-stoichiometry approach to zooplankton-phytoplankton interactions, we compare elemental composition and aspects of nutrient deficiency across a variety of marine and freshwater ecosystems. During 1992 and 1993 we sampled a total of 31 lakes (in northern Wisconsin and Michigan and the Experimental Lakes Area of northern Ontario) and 21 marine stations (at seven estuarine, co...

Elucidating subunit stoichiometry of neurotransmitter receptors is preferably carried out in a mammalian expression system where the rules of native protein assembly are strictly obeyed. Although successful in Xenopus oocytes, single subunit counting, manually counting photobleaching steps of GFP-tagged subunits, has been hindered in mammalian cells by high background fluorescence, poor control...

Accurate impedance measurements on differently sized samples of lead–zirconate–titanate (PbZr0.53Ti0.47O3, PZT) have been analyzed with a CNLS procedure, resulting in the separation of the ionic and electronic conductivities over a temperature range from f 150 to 630 jC. At 603 jC the electronic conductivity shows approximately a (PO2) 1/4 dependence, while the ionic conductivity remains consta...

by employing the theoretical method based on tight-binding, we study electronic band structure of single-wall carbon nanotube (cnt) superlattices, which the system is the made of the junction between the zigzag and armchair carbon nanotubes. exactly at the place of connection, it is appeared the pentagon–heptagon pairs as topological defect in carbon hexagonal network. the calculations are base...

background: there is some evidence indicating improvement in myocardial performance after atrial septal defect closure, either device closure or surgical, but ventricular dyssynchrony has not been evaluated before and after surgical closure. the aim of this study was to evaluate ventricular mechanical dyssynchrony in patients with atrial septal defect before and after surgical closure. methods:...