Equivalence of the realized input and output oriented indirect effects metrics in ecological network analysis

A new understanding of the consequences of how ecosystem elements are interconnected is emerging from the development and application of Ecological Network Analysis. The relative importance of indirect effects is central to this understanding, and the ratio of indirect flow to direct flow (I/D) is one indicator of their importance. Two methods have been proposed for calculating this indicator. The unit approach shows what would happen if each system member had a unit input or output, while the realized technique determines the ratio using the observed system inputs or outputs. When using the unit method, the input oriented and output oriented ratios can be different, potentially leading to conflicting results. However, we show that the input and output oriented I/D ratios are identical using the realized method when the system is at steady state. This work is a step in the maturation of Ecological Network Analysis that will let it be more readily testable empirically and ultimately more useful for environmental assessment and management.Comment: 13 pages, 1 figure, 1 tabl

Exploring morphological correlations among H2CO, 12CO, MSX and continuum mappings

There are relatively few H2CO mappings of large-area giant molecular cloud (GMCs). H2CO absorption lines are good tracers for low-temperature molecular clouds towards star formation regions. Thus, the aim of the study was to identify H2CO distributions in ambient molecular clouds. We investigated morphologic relations among 6-cm continuum brightness temperature (CBT) data and H2CO (111-110; Nanshan 25-m radio telescope), 12CO (1--0; 1.2-m CfA telescope) and midcourse space experiment (MSX) data, and considered the impact of background components on foreground clouds. We report simultaneous 6-cm H2CO absorption lines and H110\alpha radio recombination line observations and give several large-area mappings at 4.8 GHz toward W49 (50'\times50'), W3 (70'\times90'), DR21/W75 (60'\times90') and NGC2024/NGC2023 (50'\times100') GMCs. By superimposing H2CO and 12CO contours onto the MSX color map, we can compare correlations. The resolution for H2CO, 12CO and MSX data was about 10', 8' and 18.3", respectively. Comparison of H2CO and 12CO contours, 8.28-\mu m MSX colorscale and CBT data revealed great morphological correlation in the large area, although there are some discrepancies between 12CO and H2CO peaks in small areas. The NGC2024/NGC2023 GMC is a large area of HII regions with a high CBT, but a H2CO cloud to the north is possible against the cosmic microwave background. A statistical diagram shows that 85.21% of H2CO absorption lines are distributed in the intensity range from -1.0 to 0 Jy and the \Delta V range from 1.206 to 5 km/s.Comment: 18 pages, 22 figures, 5 tables. Accepted to be published in Astrophysics and Space Scienc

Performance assessment of vegetable oil-based cutting fluid developed from palm kernel oil using multi-response optimisation technique

In this work, locally sourced palm kernel oil was characterised and thereafter formulated with the aid of full factorial L1624 design method. The performances of the formulated and mineral cutting fluids were evaluated by examining the material removal rate, cutting temperature and surface roughness using Grey relational analysis (GRA) and Behnken’s design (L1533) design technique. The experimental results obtained indicate that the properties of the palm kernel oil and formulated cutting fluid falls within the preferred range for vegetable-based cutting fluids as reported in literatures. The GRA results showed an optimal turning condition of depth of cut (1.5mm), feed rate (0.3mm/rev) and cutting speed (600rev/min) for palm kernel oil-based cutting fluid while depth of cut (1.5mm), feed rate (0.2mm/rev) and cutting speed (800rev/min) is the optimal condition for mineral oil-based cutting fluid. Also, the chip formation analysis revealed continuous chips which are in conformity with ISO 3685 standards

Microbial health hazards of recycling food waste as animal feed

The use of food waste as animal feed could contribute to a more circular and sustainable food production. Feeding swill (consumption phase food waste) however, is historically associated with disease transmission to animals and humans. The aim of this paper is to review the microbial health hazards of feeding swill to farm animals, with a focus on pigs and poultry. First, the current European food waste legislation is described. In literature 60 articles describing the hazards of feeding swill to pigs and poultry were identified. Most of the articles focus on viruses, mainly at the level of animal feed and animal-based food products. Articles describing bacterial hazards and also information on the microbial hazards on the level of kitchen and table waste and food consumption level were lacking. Described management factors related to swill feeding are factors such as herd size, management practices and biosecurity. This study shows that feeding kitchen and food waste to pigs and poultry includes various microbial health hazards. Many microbial hazards in animal feed can be overcome by adequate (heat) treatments, good facilities and strict regulations. However, also other hazards, such as non-infectious pathogens, physical and chemical hazards need more insight

Mercury mobility in a salt marsh colonised by Halimione portulacoides

The present study intends to increase the knowledge on the mobility of mercury in a salt marsh colonised by Halimione portulacoides. Mercury distribution in the sediment layers and its incorporation into the plant biomass were assessed, as well as the potential export of mercury from the contaminated area to the adjacent environment. Mercury pools in the sediments ranged from 560 to 943 mg m-2 and are largely associated with the solid fraction, with just a small amount being associated with the pore waters. Estimated diffusive fluxes of reactive mercury ranged from 1.3 to 103 ng m-2 d-1. Despite the above ground biomass values being comparatively higher than below ground biomass values, the mercury pools were much higher in the root system (0.06-0.16 mg m-2 and 29-102 mg m-2, respectively). The annual bioaccumulation of mercury in above ground tissues was estimated in 0.11 mg m-2 y-1, while in below ground biomass the values were higher (72 mg m-2 y-1). The turnover rates of H. portulacoides biomass suggest higher mercury mobility within the plant rhizosphere. Taking into account the pools of mercury in above ground biomass, the export of mercury by macro-detritus following the "outwelling hypothesis" is not significant for the mercury balance in the studied ecosystem. The mercury accumulated in the below ground part of the plant is quite mobile, being able to return to the sediment pool throughout the mineralisation process.http://www.sciencedirect.com/science/article/B6V74-4SRM83C-1/1/afd89d1885b88e6149c4ae0e1e4adb5

Digitizing the Seminar Paper. A graduate student perspective on how digital tools shape scholarship

In the early twentieth century, Grand Rapids, Michigan addressed a major political scandal, which was the tipping point of municipal politics in Grand Rapids between politics rooted in personal connections and those centered on business-like administration. However, reform moved slowly, hindered by the social and spatial relationships of the élite. Using digital tools in a digital history seminar shaped my analysis of these personal and spatial relations. As a vital step in my research process, the construction of a digital project not only informed my written argument, but also fundamentally shaped it. It also reveals the importance of small scale digital research projects, made accessible through the use of open access tools, in the ultimate widespread adoption of the digital humanities