Academic literature on the topic 'Soil sciences not elsewhere classified'

Abstract Field experiments were carried out at the Teaching and Research Farm, Landmark University, Omu-Aran, Kwara State, Nigeria, in the cropping seasons of 2015 and 2016. The soil at the site of the experiment is an Alfisol classified as an Oxichaplustalf or a Luvisol. The trial consisted of sole and combined applications of urea fertilizer (U) applied at 0, 60, and 120 kg·ha−1 and maize cob ash (M) applied at 0, 3, and 6 t·ha−1. The results showed that U and M alone or in combinations increased the soil chemical properties, growth, yield, and mineral composition of okra compared with the control. M alone at 3 t·ha−1 produced optimum soil chemical properties, yield, and mineral composition of okra fruit. U alone at 60 kg·ha−1 produced optimum yield of okra, while growth and mineral composition were increased when urea fertilizer was applied at 120 kg·ha−1. The treatment with U applied at 60 kg·ha−1 in combination with M applied at 3 t·ha−1 (U60M3) produced the highest values of okra yield, while U applied at 120 kg·ha−1 in combination with M applied at 3 t·ha−1 (U120M3) has the highest growth and highest N, K, Ca, Cu, and Fe contents of okra fruit. Compared with the control and using the mean of the two years, U60M3 increased okra fruit yield by 93.3%. Therefore, for viable production of okra in low nutrient soil of the Nigeria derived savanna or similar soils elsewhere, 60 kg·ha−1 U + 3 t·ha−1 M (U60M3) is recommended. However, for improved mineral quality of okra, 120 kg·ha−1 U + 3 t·ha−1 M (U120M3) is recommended.

Runoff water harvesting (RWH) is considered as an important tool for overcoming water scarcity in arid and semi-arid regions. The present work focuses on identifying potential RWH sites in the Wadi Watir watershed in the south-eastern part of the Sinai Peninsula. This was carried out by means of significant integration of the analytical hierarchy process (AHP), distributed spatial model, geographical information system (GIS), watershed modeling system (WMS), and remote sensing techniques (RS). This integration of modern research tools has its own bearing on the accurate identification of optimum RWH sites, which could be relied upon in developmental planning for arid environments. Eight effective RWH parameters were chosen to apply a multi-parametric decision spatial model (MPDSM), namely the overland flow distance, volume of annual flood, drainage density, maximum flow distance, infiltration number, watershed slope, watershed area and watershed length. These parameters were used within ArcGIS 10.1© as thematic layers to build a distributed hydrological spatial model. The weights and ranks of each model parameter were assigned according to their magnitude of contribution in the RWH potentiality mapping using a pairwise correlation matrix verified by calculating the consistency ratio (CR), which governs the reliability of the model application. The CR value was found to be less than 0.1 (0.069), indicating acceptable consistency and validity for use. The resulting MPDSM map classified the watershed into five categories of RWH potential, ranging from very low to very high. The high and very high classes, which are the most suitable for RWH structures, make up approximately 33.24% of the total watershed area. Accordingly, four retention dams and seven ground cisterns (tanks) were proposed in these areas to collect and store the runoff water, whereby these proposed RWH structures were chosen according to the soil type and current land-use pattern. The resulting MPDSM map was validated using a topographic wetness index (TWI) map, created for the watershed. This integrative and applied approach is an important technique which can be applied in similar arid environments elsewhere.

This article offers an approach through administrative and cultural history to the problems associated with gathering and processing data for the Spanish national census of 1920, and by implication for earlier Spanish censuses. It focuses on the Basque province of Guipúzcoa, making use of correspondence between the central statistical office in Madrid, the provincial jefe de estadística and the localities, and of reports on three problematic towns within the province. The issues that emerge regarding ‘undercounting’, the definition of administrative boundaries and the classification of demographic characteristics are set in the wider context of census-taking practices and problems elsewhere in Spain and in other cultures.

High rates of deep drainage (water loss below the root-zone) in Western Australia are contributing to groundwater recharge and secondary salinity. However, quantifying potential drainage through measurements is hampered by the high degree of complexity of these systems as a result of diverse soil types, a range of crops, different rainfall regions, and in particular the inherent season-to-season variability. Simulation models can provide the appropriate means to extrapolate across time and space. The Agricultural Production Systems Simulator (APSIM) was used to analyse deep drainage under wheat crops in the Mediterranean climate of the central Western Australian wheatbelt. In addition to rigorous model testing elsewhere, comparisons between simulated and observed soil water loss, evapotranspiration, and deep drainage for different soil types and seasons confirmed the reasonable performance of the APSIM model. The APSIM model was run with historical weather records (70–90 years) across 2 transects from the coast (high rainfall zone) to the eastern edge of the wheatbelt (low rainfall zone). Soils were classified as 5 major types: deep sand, deep loamy sand, acid loamy sand, shallow duplex (waterlogging), and clay soil (non-waterlogging). Simulations were carried out on these soil types with historical weather records, assuming current crop management and cultivars. Soil water profiles were reset each year to the lower limit of plant-available water, assuming maximum water use in the previous crop. Results stressed the high degree of seasonal variability of deep drainage ranging from 0 to 386 mm at Moora in the high rainfall region (461 mm/year average rainfall), from 0 to 296 mm at Wongan Hills in the medium rainfall region (386 mm/year average rainfall), and from 0 to 234 mm at Merredin in the low rainfall region (310 mm/year average rainfall). The largest amounts of drainage occurred in soils with lowest extractable water-holding capacities. Estimates of annual drainage varied with soil type and location. For example, average (s.d.) annual drainage at Moora, Wongan Hills, and Merredin was 134 (73), 90 (61), and 36 (43) mm on a sand, and 57 (64), 26 (43), and 4 (18) mm on a clay soil, respectively. These values are an order of magnitude higher than drainage reported elsewhere under native vegetation. When not resetting the soil each year, carry-over of water left behind in the soil reduced the water storage capacity in the subsequent year, increasing long-term average deep drainage, depending on soil type and rainfall region. The analyses revealed the extent of the excess water problem that currently threatens the sustainability of the wheat-based farming systems in Western Australia.

Permafrost-affected soil stores a significant amount of organic carbon. Identifying the biological constraints of soil organic matter transformation, e.g., the interaction of major soil microbial soil organic matter decomposers, is crucial for predicting carbon vulnerability in permafrost-affected soil. Fungi are important players in the decomposition of soil organic matter and often interact in various mutualistic relationships during this process. We investigated four different soil horizon types (including specific horizons of cryoturbated soil organic matter (cryoOM)) across different types of permafrost-affected soil in the Western Canadian Arctic, determined the composition of fungal communities by sequencing (Illumina MPS) the fungal internal transcribed spacer region, assigned fungal lifestyles, and by determining the co-occurrence of fungal network properties, identified the topological role of keystone fungal taxa. Compositional analysis revealed a significantly higher relative proportion of the litter saprotroph Lachnum and root-associated saprotroph Phialocephala in the topsoil and the ectomycorrhizal close-contact exploring Russula in cryoOM, whereas Sites 1 and 2 had a significantly higher mean proportion of plant pathogens and lichenized trophic modes. Co-occurrence network analysis revealed the lowest modularity and average path length, and highest clustering coefficient in cryoOM, which suggested a lower network resistance to environmental perturbation. Zi-Pi plot analysis suggested that some keystone taxa changed their role from generalist to specialist, depending on the specific horizon concerned, Cladophialophora in topsoil, saprotrophic Mortierella in cryoOM, and Penicillium in subsoil were classified as generalists for the respective horizons but specialists elsewhere. The litter saprotrophic taxon Cadophora finlandica played a role as a generalist in Site 1 and specialist in the rest of the sites. Overall, these results suggested that fungal communities within cryoOM were more susceptible to environmental change and some taxa may shift their role, which may lead to changes in carbon storage in permafrost-affected soil.

Crop Management System (CMS) as developed in an Ionic framework with a Real-Time Firebase database for loop backing and decision support. The main two features were; Soil classification where the soil classified based on temperature, humidity, and soil properties such as soil moisture, soil nutrients, and soil PH level using Random Forest Algorithm. By Bootstrap method using Random Forest, samples from the dataset were selected & then classification trees was generated. The other feature was crop precision where the condition of the crop was and examined using temperature, humidity, soil moisture, soil PH levels, and soil nutrients (N, P, K). IoT device was used to fetch data from the field and then compare with already stored ideal values, suitable for optimal yield, in CMS database then process using the application to suggest the crop for cultivation and to optimize the usage of water and fertilizers. Currently, we classify the soil using Random Forest Algorithm & suggest the suitable crop for the classified type of soil & also measure the soil moisture and soil nutrients of agricultural field Acre based on the reading results we are suggesting the crop to is cultivated and pre-requisite which would be needed in future. The proposed method gives an accuracy of 96.5% as compared to existing methods of Artificial Neural Networks and Support Vector Machines

AbstractThe ability of soil to retain water in its profile is one of the most important soil functions. It is expressed as the water storage capacity or retention capacity of the soil, and it is primarily affected by the physical properties of the soil. Given the fact that the direct measurement of hydrological data for the soil is very difficult in terms of capacity, statistically expressed pedotransfer functions (PTF) are currently used for the indirect estimation of hydrolimits. The data most commonly used for the PTF are easy-to-measure and usually readily available soil data on particle size, bulk density, organic carbon and morphometric parameters of the environment (e.g. slope of the relief, etc.). The listed pedotransfer functions are deficient for the complex evaluation of soil cover; given disagreements about the attributes, they cannot be directly used for the vector database of classified soil-ecological units in the Slovak Republic. Therefore, we have created a model of an algorithm from selected parameters compatible with the vector database of classified soil-ecological units, which also allows for the spatial distribution of the cumulative coefficient of water retention capacity (CWRC) for the soils of the SR. The results of this evaluation are presented using case studies of the areas of Levoča and Hriňová.

Abstract. Soil classification systems are analysed in relation to the functioning and characterisation of catchments. Soil classifications are useful to create systematic order in the overwhelming quantity of different soils in the world and to extrapolate data available for a given soil type to soils elsewhere with identical classifications. However, such classifications are based on permanent characteristics as formed by the soil forming factors over often very long periods of time and this does not necessarily match with characteristics and parameters needed for functional soil characterization focusing, for example, on catchment hydrology. Hydropedology has made contributions towards functional characterization of soils as is illustrated for recent hydrological catchment studies. However, much still needs to be learned about the physical behaviour of anisotropic, heterogeneous field soils with varying soil structures during the year and the suggestion is made to first focus on improving simulation of catchment hydrology, incorporating hydropedological expertise, before embarking on a classification effort which involves major input of time and involves the risk of distraction. In doing so, we advise to also define other characteristics for catchment performance than the traditionally measured discharge rates.

The degree of soil development associated with geomorphic surfaces in the San Timoteo Badlands area (STB), California allows correlation of the surfaces. Soil development indices, based on field descriptions and laboratory analysis, provide a basis for comparison of these soils to each other and to dated soil chronosequences at Cajon Pass, Merced, and Anza, California. The soils in this study record a complex tectonic and climatic history, include preserved surfaces intermediate in soil development to those at Cajon Pass, and do not preserve a record of the major late Pleistocene to early Holocene aggradational event observed elsewhere in the region. Pedogenesis is similar to that of regional soils in southern California. With time, the profiles develop progressively thicker argillic horizons, and they increase in redness, clay, and secondary iron oxide content, and amount and thickness of clay films. With increasing soil age the ratio of dithionite-extractable Fe to total Fe increases, while the ratios of Fe2+to Fe3+and of oxalate- to dithionite-extractable Fe decrease. These trends are more subdued in the STB than elsewhere in the region, perhaps because the slightly higher temperature and lower precipitation of the STB may slow the rate of transformation of ferrihydrite to hematite. We use weighted means of soil development indices and rubification index values to compare the soils of this study to those at Cajon Pass, Merced, and Anza. Wide-range age estimates using the maximum limits of these values result in 27,500–305,000 yr for surface Q1, 43,000–570,000 yr for surface Q2, and 300,000–700,000 yr for surfaces Q3 and Q4. Weighing most heavily the nearest dated chronosequences, Anza and Cajon Pass, yields best estimates of age. This method constrains the time of formation of the Q1 surface to between 27,500 and 67,000 yr and the Q2 surface to 43,000–67,000 yr, and does not change the age estimates of the older surfaces.

The Shulie Lake Till (in which the Shulie soil developed) and Eatonville Till (in which the Westbrook soil developed) are commonly found at the surface of western Cumberland Country. The Shulie Lake Till is occasionally found overlying the Eatonville Till near the boundary of the two tills. The Shulie Lake Till is of late Wisconsinan age, but the age of the Eatonville Till is not known. Several pedons of the Shulie and Westbrook soils were observed and analyzed to determine the degree of their pedogenic development in order to estimate the relative ages of the two tills in which these soils had developed.The thickness of the solum and the amount of amorphous Fe and Al were found to be greater in the Westbrook soil than in the Shulie soil. This evidence indicates that the Eatonville Till is older than the Shulie Lake Till. However, the age difference between the tills is probably small because, after discounting differences in inherited kaolinite, the differences in composition and weathering of the clay minerals in the two soils are minor and common in Podzolic soils of late Wisconsinan age elsewhere in the Maritime Provinces. The combined pedogenic evidence indicates that the Shulie Lake and Eatonville tills are most probably of late Wisconsinan age.

Irish agriculture is becoming increasingly regulated, with restrictions on fertiliser application rates and stocking rates to reduce nitrate (NO₀⁻) leaching losses. However these regulations have been, to date, based on minimal field research. The purpose of this study was to determine the actual leaching losses of nitrate from Irish dairy pasture at a range of stocking rates, and to investigate the effectiveness of the nitrification inhibitor DCD at reducing nitrate leaching losses where these are deemed excessive. In grazed pastures, a major source of leached nitrate is the urine patch, where a high rate of N is applied in one application. This trial recorded the losses from urine and non-urine areas of pasture separately. Nitrate leaching losses from three soils were recorded using lysimeters at Johnstown Castle, Co. Wexford, over two years. Total nitrate losses were higher from the freely drained Clonakilty and Elton soils than from the heavy Rathangan soil. Mean nitrate losses from urine patches ranged from 16 - 233 kg nitrate-N / ha⁻¹, and were reduced by up to 53% when DCD was applied. DCD also reduced peak and mean nitrate-N concentrations in many cases. In addition, DCD halved the nitrous oxide (N₂O) emission factor on the Rathangan soil, caused increases in pasture N content, and increased herbage yield in some treatments. The distribution of urine patches under dairy grazing was recorded using GPS at Kilworth, Co. Cork. Cows were also found to deposit 0.359 urine patches per grazing hour. A model was produced to predict field-scale nitrate leaching losses from dairy pasture at a range of stocking rates. At 2.94 cows per hectare, the highest stocking rate, annual field N loss was below 34 kg nitrate-N ha⁻¹, mean drainage N concentrations were below 5.65 mg nitrate-N L⁻¹ (the EU drinking water guideline value), and the worst-case-scenario autumn peak concentration did not exceed 21.55 mg nitrate-N L⁻¹ (above the EU Maximum Allowable Concentration (MAC) but below the World Health Organisation (WHO) drinking water limit). DCD reduced total annual field N loss by 21% (a conservative estimate), and also reduced mean and peak nitrate concentrations. Provided fertiliser application rates are at or below 291 kg N ha⁻¹, and based on current legislative values for drinking water quality, this trial does not support any blanket restrictions on the stocking rate of Irish dairy farms. However where particularly high water quality is required, DCD shows potential as a useful tool to achieve low nitrate concentrations.

In today’s world, antimicrobial resistance is one of the biggest global health issues that mankind is facing. This most effective way to ensure a wound does not become infected is through cleanliness and continued disinfection of the wound site. There is a lack of new antimicrobial drugs coming to the market due to economical and clinical reasons, this is evident in Lord O’Neill’s 2016 report and is addressed by Professor Dame Sally Davies in Parliament, (“We have reached a critical point and must act now on a global scale to slow down antimicrobial resistance”2). Prescription drugs have led to this epidemic that was highlighted by O’Neill. The latest report (2016) by O’Neill states, it is critical to improve sanitation and hygiene, refrain from overusing antibiotics in agriculture and the environment as well as introducing rapid diagnostics and vaccines3. This is leading to the need for photodynamic antimicrobial chemotherapy (PACT) that involves the use of a reactive oxygen species (ROS), photosensitiser, and light to cause microbial death. PACT is a treatment for resistant and non-resistant pathogens that is included in the treatment of multidrug resistant infections. The approach is to use novel antimicrobial drugs topically, avoiding systemic photo-toxicity, thus leading itself towards topical infection control. Herein, we report the development of a range of novel photosensitisers based on the second generation photodynamic therapeutic dyes (PDT) that are based on the tricyclic isoalloxazine structure of riboflavin, vitamin B2. Photosensitisers were synthesised using similar strategies to the isoalloxazine for a number of reasons: e.g. photoactivity and capability of degradation. In order to investigate which photosensitisers gave the highest reactive oxygen yield, functional group changes were made on the N-phenyl ring by substituting a range of electron withdrawing/donating substituents at different positions (ortho, meta, para). The free amide moiety was used to attach the photosensitiser to a solid support that would act as proof of principal of a photosensitiser attached to a bandage. These dyes show a phototherapeutic response via a Type I and II mechanism upon illumination by light of a selected wavelength. The mechanisms produce highly toxic oxygen-species, such as radical production via Type I pathway and singlet oxygen generation by Type II, thus causing terminal damage to microbes in a short time period. The synthesised photosensitisers are illuminated using blue light (440 - 490 nm) and white light in order to monitor and compare the singlet oxygen and radical yields generated as they absorb approximately at 440 nm, thus blue light being ideal for irradiation. The outstanding singlet oxygen result generated by compound 12c of 172% and a radical production by 11c of 227% show promising generators of cytotoxic species, resulting in microbial death. The synthesised photosensitisers have been tested against two opportunistic microbes (Gram positive and Gram negative bacteria; Staphylococcus aureus (S. aureus), and Escherichia coli (E.coli). They have proven to be problematic from its presence within the healthcare system especially when found on surgical site infections. From the statistics generated for the National Health Service (NHS) in the UK we can see that 52.4 % of S. aureus, and 43.1 % E.coli originates within the hospital environment. Antimicrobial activity was observed for several compounds under different light regimes on and off the solid support. As a result, the best observed MIC value of 0.25 mM/mL was achieved for S. aureus in darkness and in blue light without the polymer support. Additionally, when these compounds were linked to a polymer support (mimicking a bandage), antimicrobial activity was retained when irradiated using blue light at 1.0 mM/mL. These results show potential towards the next generation of antimicrobial disinfection agents. In time, these compounds could be integrated into the healthcare system for use as a new generation of self- cleaning bandages towards post-operative wound disinfection rather than employing front line antimicrobials. This is a moot subject under review in parliament and former UK prime minister has highlighted the concern. In a statement recently released, he states “If we fail to act, we are looking at an almost unthinkable scenario where antibiotics no longer work and we are cast back into the dark ages of medicine" – David Cameron, UK Prime Minister2.

Stroke is the third leading cause of death in the western world, and the primary cause of adult disability. There is a great need for methods to identify patients at risk of stroke and decide appropriate treatment. The main criterion for identifying patients at risk of stroke is the percentage of the narrowing in the carotid arteries, which lead blood from the heart to the brain, which currently is quantified manually. This project is in collaboration with Blackpool Victoria Hospital and Christies Hospital in Manchester. The aim of this project is to develop software methods to improve computer-assisted carotid artery stenosis measurement based on Magnetic Resonance Images. A methodology is therefore presented, based on 3D geometry extracted from Contract-Enhanced MR Angiograms, to identify and segment the internal carotid arteries for stenosis quantification. The MRA data volume is initially automatically reduced, by locating the carotid arteries and creating two volumes of interest, each including a single set of carotids (either left or right). The artery of interest (Internal Carotid Artery - ICA) is identified in each sub-volume automatically, by tracking the carotid bifurcation and selecting the artery branch with no further arterial branches. The central axis of the ICA is consequently determined by calculating and connecting together the centres of gravity (centroids) of the 2D contours of the carotid in the axial plane. Segmentation of the ICA is carried out, perpendicular to the central axis, by applying adaptive thresholds along the ICA central axis based on local image characteristics. Hence, the cross-sectional area of the segmented ICA is then measured at different points along the vessel. The most stenotic area is identified, and a reference region is manually selected. The degree of stenosis is then quantified based on the reference and stenosed area measurements, according to the NASCET criterion. This provides a fully automated methodology to locate, identify, and measure the internal carotid stenosis. It is the first time that such complete methodology that covers the processing of the MRI data until the stenosis measurement is taken is developed and is fully automatic. The segmentation results are thoroughly evaluated against the manual delineations of two clinical experts (each performed the delineations twice), and against two popular segmentation techniques. The results were found successful and perform better than manual measurements and other current techniques. They present smaller variability than manual measurements and are able to deal with irregularities in the arterial structure, where other computerised techniques fail. The suggested methodologies seem promising and able to improve considerably both current clinical practice and other existing methodologies.

There are currently several evaluation methods suited to children within the Child-Computer Interaction (CCI) community. However, these methods are user based leaving a gap in inspection method suited to children, that is, where children will act as the inspection method evaluators. This research focused on how to design an effective and easy to use inspection method where children will perform the evaluation based on their values. To ensure that the above is met, a user centred approach and a mixed methodology was explored and finally resulted in the creation of the Inspection Method for Children (IMCH) with an accompanying guideline. This six stages method could be used by CCI researchers as a guide to develop similar methods for children, by industries to perform inspection method evaluation with children on technologies designed for children and could be used by designers to gather design criteria for children’s technology. The process undertaken within this research to develop the new method is also novel and could be adapted by new and old researchers when adapting method to suit children. Future work will focus on carrying out evaluation with wider age range of children in the method to ensure suitability of the method for more children. Comparative studies of the method with other usability method to determine the effectiveness of the method and as a refinement process to produce a validated and refined IMCH method.

The use of lipid profiles from the immobilised alga Selenastrum capricornuizim was investigated as a potential indicator of heavy metal pollution in freshwater environments. The toxicity of Cu", Zn 2 and Cd2t on algal growth was determined and the effective concentration inhibiting specific growth rate by 50 % (EC5 0) for each metal was found to be 124 pM Cu, 20 pM Zn and 5.7 pM Cd respectively. The Cu 24 EC50 value for immobilised cells was also shown to be 124 j.tM, suggesting that Cu exhibits similar toxic effects on growth in both free and immobilised cells. Studies of the effects of temperature and heavy metal exposure (Cu21, Zn 2 and Cd2 +) on S. caprzcornutum demonstrated that these factors altered the fatty acid and free sterol composition of free algal cells in batch culture. A shift in temperature from 25°C to 10°C led to an increase in the relative proportion of oleate and decrease in linoleate and parinate (18:4), together with a significant increase in the composition of ergostenol. Exposure to heavy metal ions led to an increase in oleate (with all three metals) and altered relative proportions of linoleate and parinate (changes being metal specific). Metal ion treatment also increased a22 desaturation of chondrillasterol. This characteristic lipid signature when S. capricornutum was exposed to heavy metal ions was significantly different from changes associated with other environmental factors. These changes in lipid composition upon heavy metal treatment were also observed during exposure of S. capricornuiwn to lower metal concentrations typically found in polluted environments. Studies of cells immobilised within alginate beads showed that gel confinement significantly affected the biochemistry and physiology of algal cells, with a reduction in growth rate and final cells numbers. Scanning electron microscopy demonstrated that growth was mainly limited to the bead periphery. Immobilisation altered the lipid of composition of cells as a consequence of alterations in membrane fluidity and membrane disruption. The Cu uptake from solution was greater in immobilised cells than free cells, thus gel confinement did not confer any protection to cells. The characteristic and significant changes within the lipid composition of free cells with Cu treatment were similarly observed in immobilised cells but were only apparent at 124 pM Cu. Thus lipid profiles, especially sterol composition of immobilised algal cells, may potentially be utilised as sensitive and novel indicators of heavy metal pollution in freshwater environments.

Despite improved knowledge and advanced treatments of high-grade gliomas, the overall survival rate of glioma patients remains low due to the recurrences and locations of the tumour. Evidence shows that the existence of a subpopulation of cells - cancer stem cells (CSCs) may be the major obstacle in treating gliomas. CD133 and nestin have been suggested as the markers of CSCs and natural stem cells. The primary focus of this study was to identify CD133+/nestin+ stem-like cells and discover their association with multidrug resistance (MDR) related genes, i.e. multiple drug resistance I (mdrl) gene and anti-apoptotic gene (bcl-2) in human glioma compared to normal brain tissues and cell lines. Glioma and normal astrocyte cell lines have been employed for CD133 isolating purposes to characterise the association with MDR related genotype and phenotype. The chemosensitivity of the isolated CD 133 population was investigated using chemosensitivity assay. Meanwhile, a serum deprivation method was established in this study to enrich and select CD 133+ CSCs in a glioma (GOS-3) cell line. As a secondary focus of this project, the possibility of immortalisation enzyme hTERT being a discriminative masker between normal and cancer brain stem cells and the transcriptional correlation between cd133 and bmi-lIc-myc oncogenes were investigated. For the first time, findings of the current study demonstrated that 1) there was an evident increase of CD133 gene expression in glioma compared to normal brain tissues where the latter expressed low levels of CD133, P-gp and Bcl-2 than glioma tissues, with an exception of nestin expression, 2) serum deprivation enriched CD133 expression and demonstrated a direct coexpression between CD133 and drug resistance in GOS-3 cells, 3) hTERT may not be a discriminative marker for normal and cancer brain stem cells, 4) although there was a strong transcriptional association between bmil and cmyc, there was an inverse transcriptional association between these genes and cd133 in serum deprived glioma cells, suggesting that bmil may not be essential for the maintenance of glioma stem cells, and 5) CD133+ glioma and normal brain cells showed a significantly high resistance towards chemotherapeutic drugs compared to the autologous CD133- cells. In conclusion, an improved understanding of molecules contributing to the maintenance of CSCs may lead to a combined treatment, targeting both CSCs and their protective MDR phenotypes leading eventually to attractive strategies for the treatment of gliomas.

In the mammal, anaesthetics are known to act via two distinct mechanisms, either increasing inhibition via GABAA receptors (eg. Na-thiopentone) or decreasing excitation via NIvIDA receptors (eg. ketamine). The aim of this thesis is to investigate the effects of both increased inhibition and decreased excitation at the synaptic level within an invertebrate model system, something which cannot readily be done in vertebrate systems. This was achieved by carrying out experiments using both the above mentioned anaesthetics on the whole animal, isolated brain and cultured neurons. In invertebrates it has been shown that GABA and Glutamate can be both excitatory and inhibitory, and injection of GABA into Lymnaea has been shown to result in behavioural changes in feeding, locomotion, escape reactions, male mating and respiration. Injection of Na-thiopentone into the whole animal was carried out in this investigation, in order to establish the anaesthetic response of the animal model to this barbiturate. The presence of gamma-aminobutyric acid (GABA) receptors has been demonstrated in a respiratory interneuron (RPeD1) both electrophysiologically and via molecular techniques, however inmiunostaining has proved negative in RPeD1 and follower cells VD2/3 (unidirectional excitatory synapse) and VD4 (mutual inhibitory synapse). This suggests that these neurons are not themselves GABAergic, although this investigation shows the responses of these neurons to bath and direct application of GABA. Na-thiopentone did not reliably anaesthetise Lymnaea upon injection into the sole of the foot, suggesting that Na-thiopentone binds to proteins within the snail, andlor has a low affininty for the GABAA receptor in Lymnaea. Other anaesthetic studies using propofol and ketaniine have also demonstrated a lack of anaesthetic response. RPeD1 hyperpolarised and became quiescent in response to the application of high concentrations of GABA (10 3-104M), however at lower doses (1O 8-1O 5M), no effect was observed (p < 0.05). Under these conditions simultaneous recordings from VD4 showed hyperpolarisation in response to the application of GABA, whereas VD2 and VD3 exhibited excitatory responses. Presynaptic picoinjection of GABA also resulted in hyperpolarisation and quiescence in RJeD1, but the simultaneous response in VD3 was not observed. Postsynaptic application of GABA directly to 'VD2, and VD4 however, resulted in responses similar to those seen in the whole brain. VD2 and 3 also receive input 2, which hyperpolarises RPeD1 and elicits an excitatory EPSP in VD2 and 3 as this is similar to the response observed in this experiment it is possible that the effects of input 2 on RPeD1 and VD2 & 3 are mediated by GABA. As RPeDI does not stain positively for GABA and hyperpolarises in response to the drug, it seems unlikely that the postsynaptie effects are due to presynaptic release of GABA. RPeD1 has been shown to form reciprocal synapses with VD4 both in vivo and in vitro. When perfused with GABA (lmJ'i4), both cells hyperpolarised reversibly. The postsynaptic response could be due to the action of GABA presynaptically inhibiting RPeDI, or directly on postsynaptic GABA receptors. However VD4 forms connections with other cells in the brain such as input 3 which may also have resulted in this inhibitory response. RPeD1 would however have received a simultaneous excitatory input from this interneuron. Attempts were made to establish the nature of the RPeD1JVD4 synapse in these experiments, but no synapses were evident. These experiments therefore confirm the presence of GABA receptors in RPeD1 and suggest theft presence in VD2, and VD4. This investigation confirms the findings of previous studies, that injection and bath perfusion of barbiturates does not lead to responses in Lymnaea comparable to that of the mammal. In addition to it's main target site, ketamine (a frequently used intravenous anaesthetic) has also been shown to act at cholinergic receptors. The effects of ketamine on learning and memory and apoptosis in the mammalian CNS are well recognised. Within the Lymnaea CNS, VD4 and LPeD1 form a unidirectional excitatory cholinergic synapse, and this was chosen to investigate the effects of ketamine on excitatory synaptic transmission, short term potentiation and synapse formation in the invertebrate animal model. Ketamine decreased synaptic transmission between VD4 and LPeD1 in a concentration dependent manner, but did not significantly affect short term synaptic plasticity (pc0.05). While neurite outgrowth remained extensive, actual sprouting was diminished by all doses of ketamine. Cells exhibited extensive veiling, which was not present in control cells. Percentage chemical synapse formation was reduced by all doses of ketamine, and in some cases inappropriate inhibitory chemical synapses were formed. Furthermore acute, clinically relevant levels of ketamine reduce excitatory cholinergic transmission between VD4 and LPeD1, but short term plasticity is unaffected. Nerve regeneration was seriously compromised, and formation of appropriate chemical synapses greatly reduced. This data has serious implications for the clinical - use of ketamine, particularly in pregnant women, children or critical care patients where nerve regeneration and synapse formation are of great importance and long term exposure common practice. In conclusion, this work supports that of other studies which have showed that invertebrates appear to be relatively insensitive to barbiturates, whereas ketamine appears to effect excitation in a manner similar to that in the mammal.

Antiulcer agents, notably inhibitors of gastric acid secretion, have been the most successful category of drugs to be discovered in recent years; and moreover, there are currently four such agents in the world list of top 25 best selling drugs. Histamine H2 antagonists have been the number one selling pharmaceutical product for more than a decade and inhibitors of the parietal cell HIC-ATPase, so called "proton pump inhibitors" (PPI), look set to continue this success. The proposed study was designed to establish the relative efficacy and mechanisms of action of three novel agents using both in vitro and in vivo models. The three compounds namely AG-1749 (Lansoprazole), PD-136450 and transforming growth factor alpha (TGF(x) were studied to evaluate their antisecretory and antiulccr activities. Lansoprazole, the second PPI to be developed for clinical use, is a non-competitive inhibitor of the H1C-ATPase and has recently been launched in a number of countries. PD-136450 is a competitive antagonist of central and peripheral cholecystokinin-B (CCK-B) receptors (gastrin receptor) and it under clinical development as an anxiolytic but which has actions on the stomach and pancreas. Anxiolytic drug is otherwise known as anti-anxiety drugs, which are used to treat anxiety disorders, like depression, panic disorders, phobias and many personality disorders. TOFu is a polypeptide growth factor, which acts at the EGF receptor and displays potent mitogenic and antisecretory activity. The initial study deals with the comparison of the three compounds with omeprazole and ranitidine in terms of their ability to inhibit acid secretion and their activity in a range of experimental ulcer models. Potency, duration of action and activity against a range of stimulants of acid secretion (histamine, pentagastrin and basal) was determined in anaesthetized rat models by establishing dose-response relationships. The compounds represent a spectrum of activities in as much as lansoprazole is a potent, long acting inhibitor, PD-136450 is an orally active but selective inhibitor, while TOFu has a very short duration and is only active after parenteral administration. In a view to find out the mechanism of action of these drugs on gastric acid secretion, isolated gastric glands from rabbits were employed as an in vitro technique using radiolabeled 14C-aminopyrine as a marker. The results show that lansoprazole was the most potent antisecretory agent compared to other two drugs. The second phase of the study deals with the activity of the three compounds against gastric ulcers induced by acid hypersecretion, indomethacin and stress. This study enabled us to assess the extent to which antisecretory activity per se compared with other actions such as wound healing (TGFa) or anxiolytic activity (PD-136450) contribute to ulcer healing. As other workers already established that prostaglandins and nitric oxide are involved in the cytoprotective activity, the present study investigated the influence of prostaglandin and nitric oxide by using indomethacin and L-NAME pretreatment on the cytoprotective activity of lansoprazole, PD-136450 and TGFcz. Moreover, the three drugs were tested for their activities on the mucus and bicarbonate production in the stomach. It was found that lansoprazole and TGFc increased the gastric mucus secretion while PD-136450 did not show any change. Moreover it was evidenced from this study that the protective activity of PD-136450 is associated with the influence of bicarbonate secretion from the pancreas. In conclusion, the results of this study have indicated that lansoprazole, PD- 136450 and TGFct are potent antisecretory and antiulcer agents which have great therapeutic importance.

Mature skeletal muscle fibres can be classified as type I, type IIa, type IIx or type IIb fibres according to the myosin heavy chain (MHC) isoform that they express. More broadly, type I fibres are classified as slow fibres and type IIa, IIx and IIb fibres as fast fibres. However, the phenotype of an adult skeletal muscle fibre is not fixed: it displays plasticity being capable of adapting to changing activity and loading levels by either transition towards a slower phenotype or transition towards a faster phenotype. Overall, the aims of these studies were to further investigate and define the signal transduction pathways implicated in the control of skeletal muscle fibre phenotype. The ability of a fast muscle to undergo a transition towards a slower phenotype in response to chronic low-frequency stimulation (CLFS) was assessed, via metabolic enzyme activity assays and NADH-TR staining, following blockade of the calcineurin signalling pathway. Metabolic enzyme assays and northern blots were employed to assess the changes in enzyme activities and MEC isoform expression levels following blockade of the calcineurin and ERK1/2 signalling pathways in primary cultures of rat myotubes. Differences in the levels of various signal transduction proteins/transcription factors between slow and fast muscle were investigated using western blotting. The nuclear translocation kinetics of NFAT and NF-κB in response to treatment with the calcium ionophore A23187 were investigated in L6 myotubes using immunocytochernistry. Calcineurin blockade using cyclosporin A failed to prevent a decrease in lactate dehydrogenase activity and an increase in NADH-TR staining intensity, both characteristics of a transition towards a slower phenotype, following CLFS of the fast rat tibialis anterior muscle. Blockade of the ERK1/2 pathway in primary cultures of rat myotubes using U0126 significantly decreased MHC Iβ mRNA levels and significantly increased MIHC IIx, MEC IIb and perinatal MHC mRNA levels. Calcineurin blockade significantly decreased MHC Iβ and embryonal mRNA levels and significantly increased MHC IIx mRNA levels. Calcineurin blockade also significantly increased the activities of lactate dehydrogenase and creatine kinase while ERK1/2 blockade significantly increased the activities of lactate dehydrogenase, creatine kinase, hexokinase, malate dehydrogenase and β-hydroxyacyl-CoA deydrogenase. ERK1/2 and NF-κB levels were found to be higher in slow muscle compared to fast muscle while calcineurin and p38α,β levels were higher in fast muscle compared to slow muscle. No nuclear translocation of NF-κB and only limited evidence for NFAT nuclear translocation was seen in L6 myotubes following treatment with A23187. Overall these studies further characterize the roles of the ERK1/2 and calcineurin pathways in the regulation of muscle phenotype suggesting that each pathway controls some, but not all, of the genes that are differentially expressed between slow and fast muscle fibres. Western blotting suggests further signal transduction protein/transcription factor targets, the functions of which may be explored in the future.

The problem of sediment transport and sedimentation in estuaries is examined in relation to the Boyne Estuary situated on the Central Queensland Coast. Bottom material characteristics are examined and the most appropriate formulae for prediction of sediment transport are identified.. Estuaries are natural resources that play an important role in the economic and social development of nations. They offer habitat for fish, sites for harbours, industries, and recreational activities. Sediment transport into estuaries, and the subsequent shoaling of estuaries are important estuarine processes that impact upon the physical condition (shape, depth etc) of the estuary, and therefore the uses to which the estuary can be put. As such, estuaries represent important and complex engineering problems. The sediment transport aspect of these estuarine processes is examined in this thesis with a view to quantifying the sediment transport rate in the Boyne Estuary on the Central Queensland coast of Australia. The estuary was characterised into five distinct zones using the particle size distribution of the bottom materiaL A null point, at which the velocity of the river current is effectively balanced by the velocity of the incoming tidal and coastal current was identified in one of the five zones. Analyses of the sediment transport rate were carried out using the depth of flow, mean velocity of flow, bottom roughness and characteristics of the bottom material ofthe Boyne Estuary. Sediment transport formulae reported in the literature are reviewed for this purpose with six formulae, namely, the Ackers-White formula, the Engelund-Hansen formula, the Inglis-Lacey formula, the Van Rijn formula, the Ranga Raju formula, and the Zanke formula, being selected for detailed study. Three of the six formulae (the Van Rijn formula, the Ranga Raju formula, and the Zanke formula) predict the components of the total sediment transport, namely, the bed load transport, and suspended load transport separately. The other three formulae predict the total sediment transport without any detail on the components. Wash load transport is not considered in any of the formulae. The Van Rijn formula was selected as the reference sediment transport formula and three other sediment transport formulae, namely, the Ackers-White, the Engelund-Hansen, and the Inglis-Lacey, that predict close results with the reference formula were found to be suitable for the evaluation of sedimenttransport rate in the Boyne Estuary.

Bioremediation is a prominent and novel technology among decontamination studies because of its economic practicability, enhanced proficiency, and environmental friendliness. The continuously deteriorating environment due to pollutants was taken care of by the use of various sustainable microbial processes. It is a process that uses microorganisms like bacteria and fungi, green plants, or their enzymes to restore the natural environment altered by contaminants to its native condition. Contaminant compounds are altered by microorganisms through reactions that come off as a part of their metabolic processes. Bioremediation technologies can be generally classified as in situ or ex situ. In situ bioremediation involves treating the pollutants at the site, while ex situ bioremediation involves the elimination of the pollutants to be treated elsewhere. This chapter deals with several aspects, such as the detailed description of bioremediation, factors of bioremediation, the role of microorganisms in bioremediation, different microbial processes and mechanisms involved in the remediation of contaminants by microorganisms, and types of bioremediation technologies such as bioventing, land farming, bioreactors, composting, bioaugmentation, biofiltration, and bio-stimulation.