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Managing nitrogen (N) supply to better match crop demand and reduce losses will be an important goal under future predicted elevated carbon dioxide (e[C[O.sub.2]]) conditions. This study comprised two Free-Air Carbon dioxide Enrichment (FACE) experiments conducted in southern Australia in 2011. The first experiment (Exp-1) was a field experiment that investigated the impact of a nitrification inhibitor (NI), 3,4-dimethylpyrazole phosphate (DMPP), and supplementary irrigation on utilisation of legume (field pea) residual N by a wheat crop and soil nitrous oxide ([N.sub.2]O) emissions. The second experiment (Exp-2) used [sup.15]N techniques in soil cores to investigate the impact of DMPP on recovery of fertiliser N. In Exp-1, grain N concentration increased (by 12%, P< 0.001) with NI application compared with no NI application, irrespective of C[O.sub.2] concentration ([C[O.sub.2]]) and supplementary irrigation. With NI application the grain N harvest index increased under e[C[O.sub.2]] (82%) compared with a[C[O.sub.2]] (79%). Applying the NI compensated for decreased grain copper concentration observed under e[C[O.sub.2]] conditions. NI had minimal effect on soil [N.sub.2]O emissions in the wheat crop regardless of [C[O.sub.2]]. In Exp-2, 65% ([+ or -] 1 standard error, n = 15) of the applied N fertiliser was recovered in the aboveground plant, irrespective of NI use. The use of a NI in a cereal--legume rotation may help to increase grain N concentration, increase the mobilisation of N towards the grain under e[C[O.sub.2]], and may also help to compensate for decreases in grain copper concentration under e[C[O.sub.2]]. However, use of a NI may not provide additional benefit for productivity or efficiency of N utilisation. Additional keywords: alkaline soil, ammonium, dimethylpyrazole phosphate, irrigation, [sup.15]N-labelled, nitrate, urea., Introduction Elevated carbon dioxide (e[C[O.sub.2]) stimulates plant demand for nitrogen (N) and so either more N needs to be supplied or the efficiency by which crops use this N needs [...]

The objectives of this study were to improve our understanding of seasonal variation in the biophysical disappearance of the nitrification inhibitor dicyandiamide (DCD) in soil and the key regulatory factors. Changes in DCD concentrations in the soil and plant canopy were measured following application to dairy-grazed pasture soil and nongrazed pasture soil. Treatments included two levels of DCD alone (10 and 20 kg [h.sup.-1]) applied to non-grazed pasture field plots, and DCD (10 kg [h.sup.-1]) applied with urine and with urea fertiliser. DCD (10 kg [h.sup.-1]) was also applied in grazed farmlets following grazing. About 440% of the DCD applied was intercepted and stayed on the plant canopy from Additional keywords: biophysical disappearance of DCD, dicyandiamide (DCD), grazed pasture soil, nitrification inhibitor, soil temperature., Introduction Nitrous oxide ([N.sub.2]O) contributes to an enhanced greenhouse effect, with a global warming potential 298 times greater than carbon dioxide (C[O.sub.2]) in a 100-year time horizon (Forster et al. [...]

Pena-Shokeir syndrome is a rare, early lethal disease. It is characterized by fetal growth restriction; craniofacial deformities, for example micrognathia and microcephaly; multiple ankyloses; and pulmonary hypoplasia. For patients with this syndrome, maintenance of airway and control of perioperative respiratory complications are important for anesthetic management. We report 3 pediatric cases of Pena-Shokeir syndrome undergoing tracheostomy and arthrolysis under general anesthesia using sevoflurane, nitrous oxide, fentanyl, and vecuronium bromide. Anesthetic procedures including mask ventilation, tracheal intubation, and extubation were successfully performed without complications during and after surgery. In patients with Pena-Shokeir syndrome, inhalational anesthetics can be safely used for induction and maintenance of anesthesia, although it is important to assume that difficult airway management might be encountered. Keywords Pena-Shokeir syndrome * Cerebro-oculo-facio-skeletal syndrome * Anesthetic management * Pediatric * Airway, Introduction Pena-Shokeir syndrome is an inherited disorder characterized by intrauterine growth restriction, craniofacial deformities, multiple ankyloses, and pulmonary hypoplasia [1-3]. Another phenotype referred to as cerebro-oculofacio-skeletal syndrome [4], has similar [...]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2009.04.012 Byline: A. Papageorgiou (a), J.R. Barton (b), A. Karagiannidis (a) Abbreviations: AEA, AEA Technology; AiIE, Associates in Industrial Ecology; APC, air pollution control; CHP, combined heat and power; CH.sub.4, methane; CO.sub.2, carbon dioxide; CO.sub.2-eq, carbon dioxide equivalents; DEFRA, Department for Environment Food and Rural Affairs; DOC, degradable organic carbon; DOC.sub.F, fraction DOC dissimilated; DTI, Department of Trade and Industry; EC, European Commission; EF, emission factor; EfW, energy from waste; ERM, Environmental Resources Management; FBI, fluidised bed incinerator; GCV, gross calorific value; GHG, greenhouse gas; GWP, global warming potential; HFCs, hydrofluorocarbons; IPCC, Intergovernmental panel on climate change; L.sub.0, methane generation potential; MBI, Mass Burn Incineration; MBT, mechanical biological treatment; MCF, methane correction factor; MHT, mechanical heat treatment; MSW, municipal solid waste; NCV, net calorific value; N.sub.2O, nitrous oxide; PFCs, perfluorocarbons; OX, oxidation factor; SNCR, selective non-catalytic reduction; SRF, solid recovered fuel; SF.sub.6, sulphur hexafluoride Abstract: Waste management activities contribute to global greenhouse gas emissions approximately by 4%. In particular the disposal of waste in landfills generates methane that has high global warming potential. Effective mitigation of greenhouse gas emissions is important and could provide environmental benefits and sustainable development, as well as reduce adverse impacts on public health. The European and UK waste policy force sustainable waste management and especially diversion from landfill, through reduction, reuse, recycling and composting, and recovery of value from waste. Energy from waste is a waste management option that could provide diversion from landfill and at the same time save a significant amount of greenhouse gas emissions, since it recovers energy from waste which usually replaces an equivalent amount of energy generated from fossil fuels. Energy from waste is a wide definition and includes technologies such as incineration of waste with energy recovery, or combustion of waste-derived fuels for energy production or advanced thermal treatment of waste with technologies such as gasification and pyrolysis, with energy recovery. The present study assessed the greenhouse gas emission impacts of three technologies that could be used for the treatment of Municipal Solid Waste in order to recover energy from it. These technologies are Mass Burn Incineration with energy recovery, Mechanical Biological Treatment via bio-drying and Mechanical Heat Treatment, which is a relatively new and uninvestigated method, compared to the other two. Mechanical Biological Treatment and Mechanical Heat Treatment can turn Municipal Solid Waste into Solid Recovered Fuel that could be combusted for energy production or replace other fuels in various industrial processes. The analysis showed that performance of these two technologies depends strongly on the final use of the produced fuel and they could produce GHG emissions savings only when there is end market for the fuel. On the other hand Mass Burn Incineration generates greenhouse gas emission savings when it recovers electricity and heat. Moreover the study found that the expected increase on the amount of Municipal Solid Waste treated for energy recovery in England by 2020 could save greenhouse gas emission, if certain Energy from Waste technologies would be applied, under certain conditions. Author Affiliation: (a) Laboratory of Heat Transfer and Environmental Engineering, Department of Mechanical Engineering, Box 483, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece (b) School of Civil Engineering, Faculty of Engineering, The University of Leeds, LS2 9JT Leeds, UK Article History: Received 7 August 2008; Revised 27 February 2009; Accepted 2 April 2009

The attribution of [N.sub.2]O emission factors to N inputs from chemical fertilizers requires an understanding of how those inputs affect the biological processes from which these emissions are generated. We propose a detailed model of soil N transformations as part of the ecosystem model ecosys for use in attributing [N.sub.2]O emission factors to fertilizer use. In this model, the key biological processes--mineralization, immobilization, nitrification, denitrification, root, and mycorrhizal uptake--controlling the generation of [N.sub.2]O were coupled with the key physical processes--convection, diffusion, volatilization, dissolution--controlling the transport of the gaseous reactants and products of these biological processes. Physical processes controlling gaseous transport and solubility caused large temporal variation in the generation and emission of [N.sub.2]O in the model. This variation limited the suitability of discontinuous surface flux chambers measurements used to test modeled [N.sub.2]O emissions. Continuous flux measurements using micrometeorological techniques were better suited to the temporal scales at which variation in [N.sub.2]O emission occurred and at which model testing needed to be conducted. In a temperate, humid climate, modeled [N.sub.2]O emissions rose nonlinearly with fertilizer application rate once this rate exceeded the crop and soil uptake capacities for added N. These capacities were partly determined by history of fertilizer use, so that the relationship between [N.sub.2]O emissions and current N inputs depended on earlier N inputs. A scheme is proposed in which [N.sub.2]O emission factors rise nonlinearly with fertilizer N inputs that exceed crop plus soil N uptake capacities.

Nitrous oxide [N.sub.2]O, also known as laughing gas) and volatile anesthetics (VAs), the original and still most widely used general anesthetics, produce anesthesia by ill-defined mechanisms. Electrophysiological experiments in vertebrate neurons have suggested that [N.sub.2]O and VAs may act by distinct mechanisms; [N.sub.2]O antagonizes the N-methyl-D-aspartate (NMDA) subtype of glutamate receptors, whereas VAs alter the function of a variety of other synaptic proteins. However, no genetic or pharmacological experiments have demonstrated that any of these in vitro actions are responsible for the behavioral effects of either class of anesthetics. By using genetic tools in Caenorhabditis elegans, we tested whether the action of [N.sub.2]O requires the NMDA receptor in vivo and whether its mechanism is shared by VAs. Distinct from the action of VAs, [N.sub.2]O produced behavioral defects highly specific and characteristic of that produced by loss-of-function mutations in both NMDA and non-NMDA glutamate receptors. A null mutant of nmr-1, which encodes a C. elegans NMDA receptor, was completely resistant to the behavioral effects of [N.sub.2]O, whereas a non-NMDA receptor-null mutant was normally sensitive. The [N.sub.2]O-resistant nmr-1(null) mutant was not resistant to VAs. Likewise, VA-resistant mutants had wild-type sensitivity to [N.sub.2]O. Thus, the behavioral effects of [N.sub.2]O require the NMDA receptor NMR-1, consistent with the hypothesis formed from vertebrate electrophysiological data that a major target of [N.sub.2]O is the NMDA receptor.

New combustion systems developed for low emissions have produced substantial changes to the characteristics of inlet turbulence entering nozzle guide vanes. This paper documents the characteristics of turbulence generated by mock combustion system configurations representative of recently developed catalytic and dry low N[O.sub.x] combustors. Additionally, heat transfer rates are determined on the surface of a vane subjected to inlet turbulence generated by these mock combustor configurations. Six different inlet turbulence conditions with levels ranging up to 14% are documented in this study and vane heat transfer rates are acquired at exit chord Reynolds numbers ranging from 500,000 to 2,000,000. Heat transfer distributions show the influence of turbulence level and scale on heat transfer augmentation and transition. Cascade aerodynamics are well documented and match pressure distributions predicted by a commercial CFD code for this large-scale low-speed facility. The vane pressure distribution could be characterized as a conventional or fully loaded distribution. This comprehensive data set is expected to represent an excellent test case for vane heat transfer predictive methods. Predictive comparisons are shown based on a two-dimensional boundary layer code using an algebraic turbulence model for augmentation as well as a transition model. [DOI: 10.1115/1.1559898]

There has been less research into six-membered metallacycles, especially those containing unsaturated rings, than their five-membered ring counterparts. A program to investigate the us of pentadienide and heteropentadienide reagents as possible synthons to produce unsaturated six-membered metallacycles was undertaken. Iridacyclohexadiene complexes were successfully synthesized. Also the treatment of iridabenzenes with nitrous oxide, lead to the production of irridacyclohexadienones, a further new class of unsaturated six-membered metallacycles.

Polysilicon oxides grown in pure N2O have optimum polarity asymmetry of J-E characteristic when the top electrode is positively biased. The oxide is suitable for nonvolatile memory applications. The smooth surface of the N2O-grown polyoxide provides high breakdown electric field and low leakage current. Nitrogen trapped at the polyoxide/poly-1 interface results in a higher charge-to-breakdown and a lower electron trapping rate. The centroids of the trapped charges are farther away from the polyoxide/poly-1 interface than the conventional O2-grown polyoxides.