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Nitrous oxide (N2O) is highly water soluble and can be readily transported in waters draining from agricultural fields. Relatively few studies have quantified N2O losses through agricultural tile drainage systems and none have compared the effect of different sources of applied nitrogen or their timing of application. While IPCC guidelines provide estimates of emissions from agricultural drainage water, the uncertainty in these estimates is relatively high. This research quantifies N2O loss in tile drainage water, as influenced by nitrogen source and timing. The study site was located at Agriculture Canada research station, Harrington, PE, Canada and consisted of 12 plots with subsurface drainage systems installed at approximately 80 cm, separated by buffer drains. Three swine manure treatments were considered with inorganic fertilizer (ammonium nitrate) as a control, each replicated three times. Manure treatments included fall and spring application of solid swine manure and spring application of liquid swine manure, all applied to supply 120 kg N ha−1. The magnitude of N2O loss, as measured from samples collected at the tile outlets, demonstrated significant episodic emissions. Annual cumulative dissolved N2O emissions ranged from 0.1 to 5.69 kg N ha−1 (mean 0.83 kg N ha−1), while emissions from the soil surface were 0.09–1.16 kg N ha−1 (mean 0.33 kg N ha−1). N2O emissions in tile water were not significantly affected by the form of N applied, however tile drain length significantly impacted tile water N2O concentration. IPCC coefficients for N2O emissions from agricultural drainage water would underestimate actual N2O emissions at this site. [ABSTRACT FROM AUTHOR]

A transient aplastic crisis (TAC) is a well-known complication in all types of chronic hemolytic anemia but only 2 cases of such an event were described in congenital dyserythropoietic anemias (CDAs). Here, we report a third case, and by retrospective chart review of 78 cases we found evidence of TAC in 8 further patients with CDA II, with serological evidence of previous human parvovirus B19 (B19V) infection in all but one. Although B19V infection results in TAC in only a minority of patients with CDA, physicians responsible for these patients should be aware of such a potentially life-threatening complication. Testing for B19V-specific IgG is recommended in patients with CDA to estimate the risk of a possible future aplastic crisis. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Several studies in Germany aimed at the development of a sound database on existing waste prevention measures by public bodies at the local, regional and federal levels. These results are the starting point for the creation of a national prevention program, which has to be presented by all European Member States until the end of 2013--due to the revised European Waste Framework Directive. Based on this empirical foundation, this paper draws conclusions with regard to drivers and barriers for eco-innovations in the field of waste prevention. The analysis shows that an optimized adaptation of information on waste prevention to the needs of specific target groups is still missing but could be a relevant driver. With regard to barriers the results of the study show that waste prevention is by no means always a win-win-situation. Institutional frameworks are missing to coordinate the different interests and for the exchange of experiences that could help to realize learning effects regarding innovation approaches., (Copyright © 2013. Published by Elsevier B.V.)

Defining the prevention of waste as top priority of the waste hierarchy--as confirmed by the revised Waste Framework Directive (WFD)--is much more than a simple amendment of ways to deal with waste, but means nothing less than a fundamental change of the socio-technical system of waste infrastructures and requires a transition from end-of-pipe technologies towards an integrated management of resources. The WFD therefore obligates member states to develop national waste prevention programs as a new policy instrument with the development of waste prevention indicators as one of the core elements. The article discusses the limitations of waste-based key figures and shows the need for more process-oriented indicators. As part of the development of national waste prevention programs such indicators reveal the relevance of different barriers that have to be overcome in order to make prevention an effective top priority in the waste hierarchy. With regard to path dependencies caused by sunk costs in end-of-pipe waste infrastructures the absolute amount of integrated environmental investments, as well as their share of the total waste-related investments, can be seen as indicators for the level of innovation activities aimed at waste prevention. Sector-specific indicators for the production phase could be used as benchmarks and to highlight differences in the need for policy interventions.

As illustrated by the case studies of end-of-life vehicles and waste electric and electronic equipment, the approach of an extended producer responsibility is undermined by the exports of used and waste products. This fact causes severe deficits regarding circular flows, especially of critical raw materials such as platinum group metals. With regard to global recycling there seems to be a responsibility gap which leads somehow to open ends of waste flows and a loss or down-cycling of potential secondary resources. Existing product-orientated extended producer responsibility (EPR) approaches with mass-based recycling quotas do not create adequate incentives to supply waste materials containing precious metals to a high-quality recycling and should be amended by aspects of a material stewardship. The paper analyses incentive effects on EPR for the mentioned product groups and metals, resulting from existing regulations in Germany. It develops a proposal for an international covenant on metal recycling as a policy instrument for a governance-oriented framework to initiate systemic innovations along the complete value chain taking into account product group- and resource group-specific aspects on different spatial levels. It aims at the effective implementation of a central idea of EPR, the transition of a waste regime still focusing on safe disposal towards a sustainable management of resources for the complete lifecycle of products.

Two new concepts for molecular solids, 'local similarity' and 'boundary-preserving isometry', are defined mathematically and a theorem which relates these concepts is formulated. 'Locally similar' solids possess an identical short-range structure and a 'boundary-preserving isometry' is a new mathematical operation on a finite region of a solid that transforms mathematically a given solid to a locally similar one. It is shown further that the existence of such a 'boundary-preserving isometry' in a given solid has infinitely many 'locally similar' solids as a consequence. Chemical implications, referring to the similarity of X-ray powder patterns and patent registration, are discussed as well. These theoretical concepts, which are first introduced in a schematic manner, are proved to exist in nature by the elucidation of the crystal structure of some diketopyrrolopyrrole (DPP) derivatives with surprisingly similar powder patterns. Although the available powder patterns were not indexable, the underlying crystals could be elucidated by using the new technique of ab initio prediction of possible polymorphs and a subsequent Rietveld refinement. Further ab initio packing calculations on other molecules reveal that 'local crystal similarity' is not restricted to DPP derivatives and should also be exhibited by other molecules such as quinacridones. The 'boundary-preserving isometry' is presented as a predictive tool for crystal engineering purposes and attempts to detect it in crystals of the Cambridge Structural Database (CSD) are reported.

The function of the X protein in the life cycle of mammalian hepadnaviruses is unclear. Based on tissue culture experiments it has been suggested that this protein represents a transcriptional transactivator which might be essential for the expression of the viral core gene. Here we have examined whether the activity of the human hepatitis B virus (HBV) core gene in vivo depends on X coexpression. To this end we compared core gene expression between four lineages of transgenic mice carrying the HBV core gene in cis arrangement with the X gene (cex lineage) and six lineages containing a modified construct in which the start codon of the X gene had been deleted (ce lineage). Whereas all cex lineages consistently exhibited a high-level hepatic core gene expression, the liver-specific core gene expression pattern of the ce lineages was heterogenous with four lineages virtually not expressing the core gene. This defect was due to a strongly reduced transcription since no core mRNA could be detected by Northern blotting. To test whether core gene expression could be restored by providing an intact X gene in trans, we crossbred mice of two lines which expressed no core mRNA or core protein with transgenic mice expressing the X-gene product under the transcriptional regulation of the liver-specific major-urinary-protein promoter/enhancer (MUP-X mice). The introduction of the MUP-X transgene induced core mRNA expression and core protein biosynthesis in the livers of the double-transgenic mice. This demonstrates that the X-gene product has the capacity to transactivate HBV core gene expression in vivo.