Estimation of in-canopy ammonia sources and sinks in a fertilized Zea mays field.

An analytical model was developed to describe in-canopy vertical distribution of ammonia (NH(3)) sources and sinks and vertical fluxes in a fertilized agricultural setting using measured in-canopy mean NH(3) concentration and wind speed profiles. This model was applied to quantify in-canopy air-surface exchange rates and above-canopy NH(3) fluxes in a fertilized corn (Zea mays) field. Modeled air-canopy NH(3) fluxes agreed well with independent above-canopy flux estimates. Based on the model results, the urea fertilized soil surface was a consistent source of NH(3) one month following the fertilizer application, whereas the vegetation canopy was typically a net NH(3) sink with the lower portion of the canopy being a constant sink. The model results suggested that the canopy was a sink for some 70% of the estimated soil NH(3) emissions. A logical conclusion is that parametrization of within-canopy processes in air quality models are necessary to explore the impact of agricultural field level management practices on regional air quality. Moreover, there are agronomic and environmental benefits to timing liquid fertilizer applications as close to canopy closure as possible. Finally, given the large within-canopy mean NH(3) concentration gradients in such agricultural settings, a discussion about the suitability of the proposed model is also presented.

Hybrid error correction and de novo assembly of single-molecule sequencing reads.

Single-molecule sequencing instruments can generate multikilobase sequences with the potential to greatly improve genome and transcriptome assembly. However, the error rates of single-molecule reads are high, which has limited their use thus far to resequencing bacteria. To address this limitation, we introduce a correction algorithm and assembly strategy that uses short, high-fidelity sequences to correct the error in single-molecule sequences. We demonstrate the utility of this approach on reads generated by a PacBio RS instrument from phage, prokaryotic and eukaryotic whole genomes, including the previously unsequenced genome of the parrot Melopsittacus undulatus, as well as for RNA-Seq reads of the corn (Zea mays) transcriptome. Our long-read correction achieves >99.9% base-call accuracy, leading to substantially better assemblies than current sequencing strategies: in the best example, the median contig size was quintupled relative to high-coverage, second-generation assemblies. Greater gains are predicted if read lengths continue to increase, including the prospect of single-contig bacterial chromosome assembly.

Agronomic and economic viability of Miscanthus x giganteus as a novel biofuel in the Maryland climate

Gemstone Team Biofuels

Respuesta de los rendimientos de trigo y maíz a la variación del almacenaje de agua en el suelo en la Región Pampeana

p.177-183

Presencia de Anagrus flaveolus en la Argentina parasitoide de un insecto dañino del trigo y maíz (Insecta - Hymenoptera - Mymaridae)

p.19-23

Validación de un modelo de balance hidrológico versátil para maíz en condiciones de semiáridez

p.125-132

Análisis de la sensibilidad de distintos índices del ENSO para explicar los rendimientos de maíz en la región pampeana

p.53-60

Medición de la capacidad de nitrificación mediante la técnica de incubaciones in situ en suelos cultivados con maíz

p.101-114

Estado de la vegetación y rendimientos de maíz en la provincia de Córdoba evaluados mediante datos NOAA - NDVI

p.51-55

Efectividad de la evaluación de polen en el campo para determinar androesterilidad en maíz (Zea mays ssp. mays)

p.213-220

Algunas consideraciones sobre la selección de híbridos de maíz

p.81-92

Análisis foliar en plantas de maíz II : microelementos

p.31-38

Influencia de algunas variables edáficas en la extracción de microelementos en suelos de la zona maicera núcleo

p.47-52

Análisis foliar en plantas de maíz de cultivo, I : macroelementos

p.23-30

Living sustainably: changing cultures and behaviours

2007 was a turning point on what sustainability meant for the construction industry with its new regulation and initiatives. The Government defined sustainability in terms of environmental objectives that can be measured, monitored and met. Last year was also the introduction of the Code for Sustainable Homes. This seminar explores the lessons learnt and the next stage of sustainability in terms of policy and practice.