Magnitude, form and bioavailability of fluvial carbon exports from Irish organic soils under pasture

Organic soils are widespread in Ireland and vulnerable to degradation via drainage for agriculture. The soil-landuse combination of pasture on organic soils may play a disproportionate role in regional C dynamics but is yet to receive study. Fluvial C fluxes and labile organic fractions were determined for two such sites at nested field (c.4 ha) and subcatchment scales (>40 ha); one relatively dry and nutrient rich, the other wetter and nutrient poor. Field scale flux from the nutrient poor site over 2 years was 38.9 ± 6.6 g C m⁻² yr⁻¹ with DIC > DOC > POC at 57, 32 and 11 % respectively, and 72 % DIC was comprised of above equilibrium CO₂. At the nutrient rich site, which overlies limestone geology, field scale export over an individual year was 90.4 g C m⁻² with DIC > DOC > POC at 49, 42 and 9 %, but with 90 % DIC as bicarbonate. By comparison with the nutrient poor site, the magnitude and composition of inorganic C exports from the nutrient rich site implied considerable export of soil-respiratory C as bicarbonate, and lower evasion losses due to carbonate system buffering. Labile DOC determined using dark incubations indicated small fractions (5–10 %) available for remineralisation over typical downstream transit times of days to weeks. These fractions are probably conservative as photolysis in the environment can increase the proportion of labile compounds via photocleavage and directly remineralise organic matter. This study demonstrates that monitoring at soil–water interfaces can aid capture of total landscape fluvial fluxes by precluding the need to incorporate prior C evasion, although rapid runoff responses at field scales can necessitate high resolution flow proportional, and hydrograph sampling to constrain uncertainty of flux estimates.

The Jordan canonical form for a class of weighted directed graphs

Recently, Cardon and Tuckfield (2011) [1] have described the Jordan canonical form for a class of zero-one matrices, in terms of its associated directed graph. In this paper, we generalize this result to describe the Jordan canonical form of a weighted adjacency matrix A in terms of its weighted directed graph.

Considering the relationship between freight transport and urban form

There has been much discussion since the mid-1980s about the relationship between transport and urban form. However, all of this body of research has concerned itself with passenger transport (i.e. the movement of people). This report is intended as an initial investigation into the relationship between road freight transport and urban form. Important trends in road freight transport and logistics and the land use associated with these activities are discussed. Data about road freight transport activity by heavy goods vehicles (HGVs) in Britain that has been disaggregated from a UK government survey is analysed to investigate the nature of urban freight operations in sixteen selected urban areas. This includes analysis of the efficiency and transport intensity of these operations on journeys to, from and within each urban area. Scenarios concerning urban freight operations based on reductions in length of haul, and improvements in vehicle lading factors, vehicle carrying capacities and empty running are constructed in order to investigate the potential effect of such changes on the vehicle kilometres performed on journeys to, from and within the sixteen urban areas.

Investigating relationships between road freight transport, facility location, logistics management and urban form

This paper examines road freight transport activity and its relationship with facility location, logistics management and urban form through an analysis of 14 selected urban areas in the UK. Improved understanding of this relationship will assist planners when making transport and land use decisions. The findings suggest that several geographical, spatial and land use factors have important influences on freight activity in urban areas. Commercial and industrial land use patterns affect the types and quantities of goods produced, consumed, and hence the total quantity of freight transport handled. This also influences the distances over which goods are moved and by what specific mode. There has been relatively low growth in warehousing in many of the selected areas over the last decade compared to the national average as well suburbanisation of warehousing in some locations. This affects the origin and destination of journeys visiting these facilities and typically increases the distance of such journeys. A greater proportion of road freight has been shown to be lifted on internal journeys in large urban areas than in smaller ones. Journeys within urban areas have been shown to be less efficient than journeys to and from the urban area in the 14 locations studied due to the much smaller average vehicle carrying capacities and lower lading factors for journeys within urban areas. The length of haul on journeys to and from urban areas studied was found to be greatest for those areas with a major seaport and/or which were geographically remote. This affects the road freight transport intensity of goods transport journeys.

Testing the weak-form market efficiency and the day of the week effects of some African countries

The aims of this work are twofold. On the one hand, it aims to find evidence supporting the presence of the weak form efficiency of several emerging African stock markets by using both parametric as well as non parametric tests. The results indicate that none of the markets are characterised by random walks with the exception of the South African stock market. On the other hand, this study aims to detect the presence of the day of the week effects of these African stock markets. Results show the existence of day of the week effects, that is the typical negative Monday and Friday positive effects in several stock markets.

Modular Form as a Curatorial Practice

This article discusses a curatorial approach to authorship as a model for thinking about what I describe as an iterative modular poem, a poetic text composed of appropriated segments. As a response to contemporary proliferation of literary and artistic works created by iterative means, i.e. through acts of appropriation, remixing and remediation, the article is an attempt at putting forward ‘the curatorial’ as an emerging paradigm of writing for the twenty-first century. The article approaches established paradigms of authorship, creativity and originality as inadequate with respect to contemporary experimental poetic practices to suggest a shift from creating to collecting and curating as a possible alternative model for thinking about instances of iterative creative writing. The argument focuses on Robert Fitterman’s Holocaust Museum (2011) as an example of an iterative modular poem and a text emblematic of such curatorial approach to authorship.

Direct electroanalytical determination of fluvastatin in a pharmaceutical dosage form: batch and flow analysis

The reduction of luvastatin (FLV) at a hanging mercury-drop electrode (HMDE) was studied by square-wave adsorptive-stripping voltammetry (SWAdSV). FLV can be accumulated and reduced at the electrode, with a maximum peak current intensity at a potential of approximately 1.26V vs. AgCl=Ag, in an aqueous electrolyte solution of pH 5.25. The method shows linearity between peak current intensity and FLV concentration between 1.0 10 8 and 2.7 10 6 mol L 1. Limits of detection (LOD) and quantification (LOQ) were found to be 9.9 10 9 mol L 1 and 3.3 10 8 mol L 1, respectively. Furthermore, FLV oxidation at a glassy carbon electrode surface was used for its hydrodynamic monitoring by amperometric detection in a flow-injection system. The amperometric signal was linear with FLV concentration over the range 1.0 10 6 to 1.0 10 5 mol L 1, with an LOD of 2.4 10 7 mol L 1 and an LOQ of 8.0 10 7 mol L 1. A sample rate of 50 injections per hour was achieved. Both methods were validated and showed to be precise and accurate, being satisfactorily applied to the determination of FLV in a commercial pharmaceutical.

BIWiki - Using a Business Intelligence Wiki to Form a Virtual Community of Practice for Portuguese Master's Students

Web 2.0 software in general and wikis in particular have been receiving growing attention as they constitute new and powerful tools, capable of supporting information sharing, creation of knowledge and a wide range of collaborative processes and learning activities. This paper introduces briefly some of the new opportunities made possible by Web 2.0 or the social Internet, focusing on those offered by the use of wikis as learning spaces. A wiki allows documents to be created, edited and shared on a group basis; it has a very easy and efficient markup language, using a simple Web browser. One of the most important characteristics of wiki technology is the ease with which pages are created and edited. The facility for wiki content to be edited by its users means that its pages and structure form a dynamic entity, in permanent evolution, where users can insert new ideas, supplement previously existing information and correct errors and typos in a document at any time, up to the agreed final version. This paper explores wikis as a collaborative learning and knowledge-building space and its potential for supporting Virtual Communities of Practice (VCoPs). In the academic years (2007/8 and 2008/9), students of the Business Intelligence module at the Master's programme of studies on Knowledge Management and Business Intelligence at Instituto Superior de Estatistica e Gestao de Informacao of the Universidade Nova de Lisboa, Portugal, have been actively involved in the creation of BIWiki - a wiki for Business Intelligence in the Portuguese language. Based on usage patterns and feedback from students participating in this experience, some conclusions are drawn regarding the potential of this technology to support the emergence of VCoPs; some provisional suggestions will be made regarding the use of wikis to support information sharing, knowledge creation and transfer and collaborative learning in Higher Education.

Catalytic hydrogenation of carbon dioxide to form methanol and methane

Dissertação para obtenção do Grau de Mestre em Engenharia Química e Bioquímica