The Behaviour of Plant Nutrients in Colliery Spoil of Central Scotland

The work of this thesis is concerned with the chemical analysis of coal waste of the Central Scottish Coalfield, treating this coal waste as a plant growth medium with the aim of rehabilitating it for agricultural use. There are numerous chemical and physical factors acting against plant growth and Chapters 2-4 highlight three of the main problems viz. high levels of trace elements, low phosphorus content and low levels of exchangeable cations. The physical properties of coal waste are outwith the scope of this thesis although they are discussed in Chapter 1. Chapter 1 describes the two methods of coal extraction, opencast and deep mining, the latter being the most commonly used in the United Kingdom, producing some 17.5 million tonnes of coal waste annually (at the present coal production rate) adding to that which has accumulated in the past, estimated in 1982 at 3,000 million tonnes covering 13,000 hectares of land. One of the main problems encountered in spoil reclamation is the heterogeneous nature of the material and the considerable differences in chemical and physical properties found between sites, each site requiring careful study at each stage of operation. Coupled with this are the changes which occur in the spoil on exposure, particularly the oxidation of iron pyrites (FeS2), producing sulphuric acid which threatens plant establishment and also attacks the spoil matrix. Chapter 2 examines the problem of high levels of available trace elements found in colliery spoil and their uptake by plants, five elements being chosen for study, namely Fe, Al, Mn, Cu and Zn, although there are many others which are limiting to plant growth. A comparison was made of the trace element content of perennial ryegrass (Lolium perenne) grown on a reclaimed spoil and an arable soil to determine the sites of requirement or deposition within the plant. A field trial was set up to determine the effects of addition of lime and organic amendments to spoil on the trace element content of the sward, results being presented for the first harvest taken after eleven weeks growth. Due to the short growing time no conclusions can be drawn from the organic amendment trial although the effects of trace element content on plant yield are discussed. After nitrogen, phosphorus is the element most restrictive to plant growth in colliery spoil. Chapter 3 discusses the problem of low levels of available phosphorus and the capacity of the spoil to fix phosphorus in an unavailable form through adsorption on hydrous oxides of iron and aluminium. A growth experiment under controlled conditions in which varying levels of lime and phosphorus fertilizer were added to three spoils showed that both spoil pH and phosphorus deficiency are major factors limiting plant growth. Chapter 4 discusses the cation exchange capacity and exchangeable base content of colliery spoil i. e. the ability of the material to hold cations in a form which may be released to the spoil solution for plant uptake and the levels of exchangeable Ca2+, Mg2+, K+ and Na+ found in a range of spoil samples. Results show that the amorphous iron and aluminium oxides in the spoil are adsorbed on exchange sites, while the amorphous manganese fraction, itself being negatively charged, may hold nutrient cations in an available form. Colliery spoil being a poor growth medium requiring the addition of high rates of fertilizers for plant growth may be reclaimed more successfully, if more expensively, by the use of a soil cover. Chapter 5 reviews the advantages of the use of soil in spoil reclamation based on evidence collected from 13 reclaimed sites in Central Scotland, these being described fully in Appendix II. This study shows that these advantages, however, may be greater if the nature of the underlying spoil was first considered, as the soil layer does not completely remove the plant from the effects of the spoil

Impact of environmental inputs on reverse-engineering approach to network structures

Background: Uncovering complex network structures from a biological system is one of the main topic in system biology. The network structures can be inferred by the dynamical Bayesian network or Granger causality, but neither techniques have seriously taken into account the impact of environmental inputs. Results: With considerations of natural rhythmic dynamics of biological data, we propose a system biology approach to reveal the impact of environmental inputs on network structures. We first represent the environmental inputs by a harmonic oscillator and combine them with Granger causality to identify environmental inputs and then uncover the causal network structures. We also generalize it to multiple harmonic oscillators to represent various exogenous influences. This system approach is extensively tested with toy models and successfully applied to a real biological network of microarray data of the flowering genes of the model plant Arabidopsis Thaliana. The aim is to identify those genes that are directly affected by the presence of the sunlight and uncover the interactive network structures associating with flowering metabolism. Conclusion: We demonstrate that environmental inputs are crucial for correctly inferring network structures. Harmonic causal method is proved to be a powerful technique to detect environment inputs and uncover network structures, especially when the biological data exhibit periodic oscillations

The Revision of Japans Early Commercial Treaties.

A joint symposium between the Japan Society and the London School of Economics and Political Science was held in the Suntory and Toyota International Centres for Economics and Related Disciplines on 9 July 1999 to mark the centenary of Treaty Revision in Japan. In the Bakumatsu period of the 1850s and 1860s Japan had entered into a number of commercial treaties with foreign countries which (among other things) gave foreign nationals extraterritorial rights in Japanese treaty ports. These treaties were re-negotiated with the individual countries in the 1890s and the new treaties came into effect in July-August 1899. Hence the centenary. The four speakers covered the full period from the conclusion of the first treaties in the 1850s to the re-negotiation of the treaties in 1911. Sir Hugh Cortazzi dealt with the various initiatives which led to the first commercial treaties with Japan between 1853 and 1868. Dr James Hoare, in dealing with the working of the early treaties and the attitudes of the foreign communities in the treaty ports, pointed out that the treaties had been modified many times. Dr Nigel Brailey spoke on Sir Ernest Satow who as British minister to Japan from 1895 was the responsible official as the 'unequal treaties' were coming to an end. He had earlier been minister in Bangkok and knew how strongly the Thais wanted their 'unequal treaties' revised at that time. While the question of jurisdiction under the treaties had been largely settled, the question of Japan's tariff autonomy remained unresolved. Dr Ayako Hotta-Lister in the final paper gave an account of how the Japanese, in a mood of increased confidence after the Russo-Japanese war, ended the earlier treaties with a view to concluding the Anglo-Japanese Tariff Treaty of 1911. By this re-negotiation Japan secured tariff autonomy and improved the terms of the commercial treaty but allowed concessions to Britain who had been her ally for almost a decade. Japan's struggle for treaty and tariff

Otx but Not Mitf Transcription Factors Are Required for Zebrafish Retinal Pigment Epithelium Development

Otx and Mitf transcription factors have been implicated in the development of the retinal pigmented epithelium (RPE), but the relationship between these factors and their specific roles in the development of the RPE have not been fully defined. The role of the three Otx transcription factors (Otx1a, Otx1b, and Otx2) and two Mitf transcription factors (Mitfa and Mitfb) in the development of the zebrafish RPE was explored in these experiments. The loss of Otx activity through morpholino knockdown produced variable eye defects, ranging from delayed RPE pigmentation to severe coloboma, depending on the combination of Otx factors that were targeted. Expression analysis through in situ hybridization demonstrates that otxtranscription factors are necessary for the proper expression of mitfa and mitfb while Mitf transcription factors are not required for the expression of otx genes. Surprisingly, the loss of Mitf activity in mitfa, mitfb, or double mitf mutant zebrafish had no effect on RPE pigmentation or development. Moreover, histological analysis revealed that retinal lamination is unaffected inmitf mutants, as well as in otx morphants, even in regions lacking RPE. Otx and Mitf combined loss of function experiments suggest that mitfa and mitfb may still influence zebrafish RPE development. This is further supported by the ability of mitfa to induce pigmentation in the zebrafish retina when misexpressed. These findings suggest that one or more Otx targets in addition to mitfa and mitfb, possibly another mitf family member, are necessary for development of the RPE in zebrafish