559 research outputs found
Heathland Restoration Techniques: Ecological Consequences for Plant-Soil and Plant-Animal Interactions
We compare the soil and plant community development during heathland restoration on improved farmland when achieved
through soil stripping with that achieved through soil acidification. We also test the potential for toxic metals to be made more available to plant and animal species as a result of these treatments. Acidification with elemental sulphur was found to be more effective than soil stripping for establishing an ericaceous sward despite the high levels of phosphate still present within the soil.However, both soil acidification and soil stripping were found to have the potential to increase the availability of potentially toxic metals. Acidification increased uptake of both aluminium and zinc in two common plant species Agrostis capillaris and Rumex acetosella and decreased the abundance of surface active spiders. The potential consequences for composition of restored heathland
communities and for functioning of food chains are discussed
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Stratigraphic visualisation for archaeological investigation
This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.The principal objective of archaeology is to reconstruct in all possible ways the life of a community at a specific physical location throughout a specific time period. Distinctly separate layers of soil provide evidence for a specific time period. Discovered artefacts are most frequently used to date the layer. An artefact taken out of context is virtually worthless; hence the correct registration of the layer in which they were uncovered is of great importance. The most popular way to record temporal relationships between stratigraphic layers is through the use of the 2D Harris Matrix method. Without accurate 3D spatial recording of the layers, it is difficult if not impossible, to form new stratigraphic correspondences or correlations.
New techniques for archaeological recording, reconstruction, visualisation and interpretation in 3D space are described in these works and as a result software has been developed. Within the developed software system, legacy stratigraphy data, reconstructed from archaeological notebooks can be integrated with contemporary photogrammetric models and theodolite point data representations to provide as comprehensive a reconstruction as possible.
The new methods developed from this research have the capability to illustrate the progression of the excavation over time. This is made possible after the entry of only two or more strata. Sophisticated, yet easy-to-use tools allow the navigation of the entire site in 3D. Through the use of an animation-bar it is possible to replay through time both the excavation period and the occupation period, that is to say the various time periods in antiquity when human beings occupied these locations.
The lack of complete and consistent recording of the soil layers was an issue that proved to be an obstacle for complete reconstruction during the development of these methods. A lack of worldwide archaeological consensus on the methods of stratigraphic recording inhibited development of a universal scientific tool. As a result, new recording methods are suggested to allow more scientific stratigraphic reconstruction
The Path Home: Dismantling the Supremacy of Real Estate
Review of Samuel Stein, Capital City. A critical account of the age of real-estate capital and the transformation of the city
MicroRNAs influence reproductive responses by females to male sex peptide in Drosophila melanogaster
Across taxa, female behavior and physiology changes significantly following the receipt of ejaculate molecules during mating. For example, receipt of sex peptide (SP) in female Drosophila melanogaster significantly alters female receptivity, egg production, lifespan, hormone levels, immunity, sleep and feeding patterns. These changes are underpinned by distinct tissue- and time-specific changes in diverse sets of mRNAs. However, little is yet known about the regulation of these gene expression changes, and hence the potential role of microRNAs (miRNAs), in female post-mating responses. A preliminary screen of genomic responses in females to receipt of SP suggested that there were changes in the expression of several miRNAs. Here we tested directly whether females lacking four of the candidate miRNAs highlighted (miR-279, miR-317, miR-278 and miR-184) showed altered fecundity, receptivity and lifespan responses to receipt of SP, when mated once or continually to SP null or control males. The results showed that miRNA-lacking females mated to SP null males exhibited altered receptivity, but not reproductive output, in comparison to controls. However, these effects interacted significantly with the genetic background of the miRNA-lacking females. No significant survival effects were observed in miRNA-lacking females housed continually with SP null or control males. However, continual exposure to control males that transferred SP resulted in significantly higher variation in miRNA-lacking female lifespan than did continual exposure to SP null males. The results provide the first insight into the effects and importance of miRNAs in regulating post-mating responses in females
Silent speech: restoring the power of speech to people whose larynx has been removed
Every year, some 17,500 people in Europe and North America lose the power of speech after undergoing a laryngectomy, normally as a treatment for throat cancer. Several research groups have recently demonstrated that it is possible to restore speech to these people by using machine learning to learn the transformation from articulator movement to sound. In our project articulator movement is captured by a technique developed by our collaborators at Hull University called Permanent Magnet Articulography (PMA), which senses the changes of magnetic field caused by movements of small magnets attached to the lips and tongue. This solution, however, requires synchronous PMA-and-audio recordings for learning the transformation and, hence, it cannot be applied to people who have already lost their voice. Here we propose to investigate a variant of this technique in which the PMA data are used to drive an articulatory synthesiser, which generates speech acoustics by simulating the airflow through a computational model of the vocal tract. The project goals, participants, current status, and achievements of the project are discussed below.Universidad de MĂĄlaga. Campus de Excelencia Internacional AndalucĂa Tech
Modifying soil chemistry to enhance heathland recreation: a use for sulphur captured during oil refining
The overall aim of this paper is to evaluate potential new modifications to methods for re-creating heathland habitats. Heathlands need acidic soils so the specific objectives are to evaluate the effectiveness of a new method for heathland re-creation by soil acidification using a sulphur soil amendment and to explore the benefits for re-creation of applying a soil stripping treatment in conjunction with soil acidification. A new source of sulphur was recovered from oil refinery towers and applied over agricultural sites covering a total of 13 ha on Trehill Farm, Marloes, Pembrokeshire, Wales, UK in 2004. In the summer of 2011 we compared soil chemistry and plant communities on sites subjected to different sulphur treatments (sulphur applied to the existing soil surface and sulphur applied after top soil had been stripped) with those on an adjacent untreated control and on a nearby established heathland. Each of the four treatment sites and the control and heath site was surveyed using 10 random locations measuring 4m x 4m. The total above ground % cover was measured for each plant species and a bulk soil sample was taken in a âWâ shape from within each 4m x 4m quadrat. pH and all chemical parameters of the soil showed highly significant differences amongst the sampled sites (P>0.01 in all cases) and produced even greater abundance of ericaceous species on some of the treated sites than occurred in the established heath. However, soil stripping had no significant additional effect on either edaphic factors or plant species abundances. Sulphur recovered from oil refinery is a potentially useful tool in heathland re-creation, but soil stripping prior to sulphur amendment did not enhance success. We propose that sulphur application drives success through increasing H+ toxicity reducing the availability of base cations and creating Fe-induced Mn deficiency in plants
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