Ammonia volatilization following surface application of raw and treated liquid swine manure

The treatment of liquid swine manure (LSM) is primarily intended to produce energy and/or decrease P concentration in the liquid fraction, but may have a simultaneous impact on its potential for N volatilization. We compared NH₃ volatilization in the field following surface application (May 2004; May 2005; September 2005) of untreated LSM and the liquid fraction of LSM (hereafter called treated LSM) that had undergone either natural decantation, filtration, anaerobic digestion, or anaerobic digestion + flocculation. Though most treatments increased pH and the proportion of total ammoniacal N (TAN) in LSM, the proportion of applied TAN lost as NH₃ was 22% lower with treated than untreated LSMs. Most likely, the increased infiltration rate of treated LSMs, associated with reduction in dry matter, compensated for increases in TAN and pH. Emissions of NH₃ on the day of application were correlated with LSM pH (R ² = 0.51) and were the highest with the digested and the digested + flocculated LSMs. However, these LSMs generally emitted less NH₃ than the other LSMs on the following days. As a consequence, when the volatilization period was short (e.g., dry soil conditions), the proportion of applied N lost from the digested and the digested + flocculated LSMs was similar or higher than the filtered and decanted LSMs. In contrast, when the volatilization period was long, the digested and digested + flocculated LSMs emitted less NH₃ than the other treated LSMs. It can be concluded that LSM treatments tended to decrease NH₃ volatilization, compared to the untreated LSM; across application dates, the digested LSM most consistently reduced NH₃-N losses whereas the filtered LSM was the least efficient.     

Carbon futures and macroeconomic risk factors: A view from the EU ETS

This article examines the empirical relationship between the returns on carbon futures – a new class of commodity assets traded since 2005 on the European Union Emissions Trading Scheme (EU ETS) – and changes in macroeconomic conditions. By using variables which possess forecast power for equity and commodity returns, we document that carbon futures returns may be weakly forecast on the basis of two variables from the stock and bond markets, i.e. equity dividend yields and the “junk bond” premium. Our results also suggest that the forecast abilities of two variables related to interest rates variation and economic trends on global commodity markets, respectively the U.S. Treasury bill yields and the excess return on the Reuters/CRB Index, are not robust on the carbon market. This latter result reinforces the belief that the EU ETS is currently operating as a very specific commodity market, with distinct fundamentals linked to allowance supply and power demand. The sensitivity of carbon futures to macroeconomic influences is carefully identified following a sub-sample decomposition before and after August 2007, which attempts to take into account the potential impact of the “credit crunch” crisis. Collectively, these results challenge the market observers' viewpoint that carbon futures prices are immediately correlated with changes in the macroeconomic environment, and rather suggest that the carbon market is only remotely connected to macroeconomic variables. The economic logic behind these results may be related to the fuel-switching behavior of power producers in influencing primarily carbon futures price changes.     

The impact of Australian ETS news on wholesale spot electricity prices: An exploratory analysis

This article investigates the impact of news concerning the development of emissions trading in Australia (such as the Carbon Pollution Reduction Scheme (CPRS)) on wholesale electricity spot prices, by using a database of 117 news announcements from December 1, 1998 to July 1, 2009. As power producers constitute the bulk of the participants of the proposed Australian emissions trading scheme, regulatory changes (about allocation, banking, coverage, targets) are indeed likely to affect the five interconnected electricity markets in New South Wales, Queensland, South Australia, Victoria, and Tasmania. We assess these effects with an ARMA(1,1)-GARCH(1,1) model, where daily electricity spot prices are regressed against exogenous variables in the mean and variance equations. This article constitutes the first empirical analysis of Australian ETS news effects on electricity wholesale spot prices. Our results show two asymmetric types of news effects, depending on their information content.     

Analysis of composite structure and primordial wood remains in petrified wood

Among all the fossils, petrified wood belongs to the most impressive and most common of materials. Still, its study has not exceeded the purely phenomenological level. The recognition of the conserved structure of petrified wood seems to be of meaning for understanding the geological past, the complete carbon cycle inside the Earth, and the structure of potential new materials. The first ever published spatial distributions of the remains of the primordial organic material (lignin, cellulose, pectins) in the cells of permineralized wood, from Dunarobba (Central Italy), are presented here. They were collected using micro-Raman spectrometry. The composite nature of the petrified material (calcite located in the lumena of cells and goethite located in the cell walls) was confirmed by electron, proton, and X-ray microprobes. The structure of the cell walls was well preserved. The mineralization process was induced by the tracheidal water flow and was stopped after formation of pipe-like goethite shielding of the cell walls on the cellulose scaffolds. The chemical (Eh and pH ranges) and probable microbial conditions for such a pattern of mineralization were determined. We estimate that substantial amounts of the primordial organic matter were preserved in bodies of petrified wood on a global scale. The wood petrifaction process, if well understood, can be a basis for the production of "everlasting" organic-inorganic composite compounds.     

Residue-specific immobilization of protein molecules by size-selected clusters

The atomic force microscope (AFM), operating in contact mode, has been employed in buffer solution to study two proteins; (i) green fluorescent protein (GFP), from the hydromedusan jellyfish Aequorea victoria; and (ii) human oncostatin M (OSM), in the presence of size-selected gold nanoclusters pinned on to a highly oriented pyrolytic graphite substrate. The AFM images have revealed immobilization of single molecules of OSM, which are strongly bound to the gold nanoclusters. Conversely, no strong immobilization has been observed for the GFP, as these molecules were easily displaced by the scanning tip. The contrasting behaviour of the two proteins can be explained by the exposed molecular surface area of their cysteine residues as modelled on the basis of their respective X-ray crystallographic data structures. GFP contains two cysteine residues, but neither is readily available to chemisorb on the gold clusters, because the cysteines are largely inaccessible from the surface of the protein. In contrast, OSM has a total of five cysteine residues, with different degrees of accessibility, which make the protein amenable to anchoring on the nanoclusters. Statistical analysis of the height of the OSM molecules bound to the nanoclusters is in accordance with crystallographic data, and suggests various configurations of the proteins on the clusters, associated with the presence of different cysteine anchoring sites. These results suggest that the three-dimensional conformation of protein molecules is preserved when they are chemisorbed to size-selected gold clusters, thus opening a new route towards oriented immobilization of individual protein molecules.     

Dog-bone copper specimens prepared by one-step spark plasma sintering

Copper dog-bone specimens are prepared by one-step spark plasma sintering (SPS). For the same SPS cycle, the influence of the nature of the die (graphite or WC–Co) on the microstructure, microhardness, and tensile strength is investigated. All samples exhibit a high Vickers microhardness and high ultimate tensile strength. A numerical electro-thermal model is developed, based on experimental data inputs such as simultaneous temperature and electrical measurements at several key locations in the SPS stack, to evaluate the temperature and current distributions for both dies. Microstructural characterizations show that samples prepared using the WC–Co die exhibit a larger grain size, pointing out that it reached a higher temperature during the SPS cycle. This is confirmed by numerical simulations demonstrating that with the WC–Co die, the experimental sample temperature at the beginning of the dwell is higher than the experimental control temperature measured at the outer surface of the die. This difference is mostly ascribed to a high vertical thermal contact resistance and a higher current density flowing through the WC–Co punch/die interface. Indeed, simulations show that current density is maximal just outside the copper sample when using the WC–Co die, whereas by contrast, with the graphite die, current density tends to flow through the copper sample. These results are guidelines for the direct, one-step, preparation of complex-shaped samples by SPS which avoids waste and minimizes machining.     

Atomic force microscopy of electrospun organic-inorganic lipid nanofibers

An organic-inorganic hybridization strategy has been proposed to synthesize polymerizable lipid-based materials for the creation of highly stable lipid-mimetic nanostructures. We employ atomic force microscopy (AFM) to analyze the surface morphology and mechanical property of electrospun cholesteryl-succinyl silane (CSS) nanofibers. The AFM nanoindentation of the CSS nanofibers reveals elastic moduli of 55.3?±?27.6 to 70.8?±?35 MPa, which is significantly higher than the moduli of natural phospholipids and cholesterols. The study shows that organic-inorganic hybridization is useful in the design of highly stable lipid-based materials.     

Histiocytoid cardiomyopathy: a cause of sudden death in infancy

We report the case of an infant aged of 14 months deceased of sudden death. The diagnosis of histiocytoid cardiomyopathy was made on a necropsic basis. The pathologic examination showed a cardiac hypertrophy characterized by yellowish areas with irregular outlines, disseminated in the myocardium, and made of histiocyte-like cells with foamy or granular cytoplasm. These cells reacted positively with desmin and myoglobin labels, and had rare and disorganised myofibrils in electron microscopy, proving their muscular origin. The illness affects infants and usually causes severe cardiac troubles leading to death without treatment. This case is the fourteenth associated with sudden death.     

Price drivers and structural breaks in European carbon prices 2005–2007

This article aims at characterizing the daily price fundamentals of European Union Allowances (EUAs) traded since 2005 as part of the Emissions Trading Scheme (ETS). The presence of two structural changes on April 2006 following the disclosure of 2005 verified emissions and on October 2006 following the European Commission announcement of stricter Phase II allocation allows to isolate distinct fundamentals evolving overtime. The results extend previous literature by showing that EUA spot prices react not only to energy prices with forecast errors, but also to unanticipated temperatures changes during colder events. Besides, the sub-period decomposition of the pilot phase gives a better grasp of institutional and market events that drive allowance price changes.