The impact of nitrogen fertilization on cotton plants, Gossypium hirsutum L., silverleaf whitefly, Bemisia argentifolii Bellows & Perring, population dynamics and honeydew production were investigated in the field at Riverside, California, USA. Treatments were soil applications of 0, 112, 168 and 224 kg nitrogen per hectare, and a soil application of 112 kg of nitrogen plus a foliar application...

 In this article, we report an attempt of extending the InGaAsN materials towards 1.3μm and 1.55μm wavelength. All these InGaAsN samples are grown in a plasma-assisted solid-source molecular-beam epitaxy (SSMBE) system. Our experiments revealed that the nitrides could be grown with both direct nitrogen beam and dispersive nitrogen. The nitrogen incorporation rate could be reduced by the presen...

A computational framework is presented for describing the nucleation and growth of vacancy clusters in crystalline silicon. The overall approach is based on a parametrically consistent comparison between two representations of the process in order to provide a systematic method for probing the details of atomic mechanisms responsible for aggregation. In this paper, the atomistic component of th...

We propose a dynamical model depicting nitrogen (N2) fixation (diazotrophy) in a unicellular cyanobacterium, Crocosphaera watsonii, grown under light limitation and obligate diazotrophy. In this model, intracellular carbon and nitrogen are both divided into a functional pool and a storage pool. An internal pool that explicitly describes the nitrogenase enzyme is also added. The model is success...

An approach is outlined for synthesising current understanding of nitrogen dynamics in natural grasslands and extensively managed grassland systems. The increasing complexity of models is illustrated from recent literature, first conceptualising and eventually process-simulating the dynamics of nitrogen, especially in the soil sub-systems of grasslands. Some comparisons are made between New Zea...

The focus of eutrophication research has tended to be upon short-term and experimental studies. However, given the range of factors that can influence eutrophication dynamics, and that these matter over a range of time scales, some discrete, some continuous, eutrophication dynamics may only be fully investigated when long-term, time-series data are available. The present study aims to evaluate ...

(15)N spin relaxation data have provided a wealth of information on protein dynamics in solution. Standard R(1), R(1)(rho), and NOE experiments aimed at (15)N[(1)H] amide moieties are complemented in this work by HA(CACO)N-type experiments allowing the measurement of nitrogen R(1) and R(1)(rho) rates at deuterated (15)N[(2)D] sites. Difference rates obtained using this approach, R(1)((15)N[(1)H...

NH3 is an essential molecule as a nitrogen source for prebiotic amino acid syntheses such as the Strecker reaction. Previous shock experiments demonstrated that meteorite impacts on ancient oceans would have provided a considerable amount of NH3 from atmospheric N2 and oceanic H2O through reduction by meteoritic iron. However, specific production mechanisms remain unclear, and impact velocities...

We have computed the free energy profiles of the deprotonation reactions of lumiflavin in the semiquinone and fully reduced oxidation states using constrained DFT-based molecular dynamics simulations. In the semiquinone state, the N5 nitrogen atom and the N1 nitrogen atom can become protonated. We find, in agreement with experiment, that the N5 site is the predominant proton acceptor in the sem...

Management of the nitrogen cycle has been identified as one of fourteen grand challenges for engineering and is an especially important issue for agricultural watersheds of the Upper Midwest. In large river systems, it has become increasingly important to understand the interactions between abiotic and biotic processes that influence nitrogen cycling. Native freshwater mussels are one of the mo...