Colour image coding with wavelets and matching pursuit

This thesis considers sparse approximation of still images as the basis of a lossy compression system. The Matching Pursuit (MP) algorithm is presented as a method particularly suited for application in lossy scalable image coding. Its multichannel extension, capable of exploiting inter-channel correlations, is found to be an efficient way to represent colour data in RGB colour space. Known problems with MP, high computational complexity of encoding and dictionary design, are tackled by finding an appropriate partitioning of an image. The idea of performing MP in the spatio-frequency domain after transform such as Discrete Wavelet Transform (DWT) is explored. The main challenge, though, is to encode the image representation obtained after MP into a bit-stream. Novel approaches for encoding the atomic decomposition of a signal and colour amplitudes quantisation are proposed and evaluated. The image codec that has been built is capable of competing with scalable coders such as JPEG 2000 and SPIHT in terms of compression ratio.

Performance of five different electrospray ionisation sources in conjunction with rapid monolithic column liquid chromatography and fast MS/MS scanning

The performances of five different ESI sources coupled to a polystyrene-divinylbenzene monolithic column were compared in a series of LC-ESI-MS/MS analyses of Escherichia coli outer membrane proteins. The sources selected for comparison included two different modifications of the standard electrospray source, a commercial low-flow sprayer, a stainless steel nanospray needle and a coated glass Picotip. Respective performances were judged on sensitivity and the number and reproducibility of significant protein identifications obtained through the analysis of multiple identical samples. Data quality varied between that of a ground silica capillary, with 160 total protein identifications, the lowest number of high quality peptide hits obtained (3012), and generally peaks of lower intensity; and a stainless steel nanospray needle, which resulted in increased precursor ion abundance, the highest-quality peptide fragmentation spectra (5414) and greatest number of total protein identifications (259) exhibiting the highest MASCOT scores (average increase in score of 27.5% per identified protein). The data presented show that, despite increased variability in comparative ion intensity, the stainless steel nanospray needle provides the highest overall sensitivity. However, the resulting data were less reproducible in terms of proteins identified in complex mixtures -- arguably due to an increased number of high intensity precursor ion candidates.

The influence of harvest and storage on the properties of and fast pyrolysis products from Miscanthus x giganteus

The research investigates the fuel property variations associated with the time of harvest and the duration of storage of Miscanthus x giganteus over a one year period. The crop has been harvested at three different times: early (September 2009), conventional (April 2010) and late (June 2010). Once harvested the crop was baled and stored. Biomass properties of samples taken from different storage zones were compared. The thermochemical properties have been investigated using a range of analytical equipment including thermogravimetric analysis (TGA) and pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS). In addition, bio-oil has been produced from the early, conventional and late harvest using a laboratory scale (300gh) fast pyrolysis unit. The potential organic liquid yield (ondry basis, also excluding the reaction water generated) based on the laboratory fast pyrolysis processing undertaken in this study, was found to vary between 2.82 and 3.18 dry tha for the early and the late harvest respectively. The bio-oil organic yield was reduced by approximately 11% (0.36tha) between the early and the late harvest. Char yield was also reduced by approximately 18% (0.61tha). The highest gas yield (18.03%-1.60tha) was observed for the conventional harvest. Gas chromatography-mass spectrometry (GC-MS) analysis of the bio-oil shows that levoglucosan, methylbenzaldehyde and 1,2-benzenediol all increase as a consequence of delayed harvest. It was also observed that by delaying the harvest time the O:C atomic ratio is reduced and a more carbonaceous feedstock is produced. © 2013 Elsevier Ltd.

Understanding knowledge coordination dynamics in traditional and fast-response IT organizations

This research takes a dynamic view on the knowledge coordination process, aiming to explain how the process is affected by changes in the operating environment, from normal situations to emergencies in traditional and fast-response organizations, and why these changes occur. We first conceptualize the knowledge coordination process by distinguishing between four dimensions - what, when, how and who - that together capture the full scope of the knowledge coordination process. We use these dimensions to analyze knowledge coordination practices and the activities constituting these practices, in the IT functions of traditional and fast-response (military) organizations where we distinguish between "normal" and "emergency" operating conditions. Our findings indicate that (i) inter-relationships between knowledge coordination practices change under different operating conditions, and (ii) the patterns of change are different in traditional and fast-response organizations.

Energy conversion assessment of vacuum, slow and fast pyrolysis processes for low and high ash paper waste sludge

The performance of vacuum, slow and fast pyrolysis processes to transfer energy from the paper waste sludge (PWS) to liquid and solid products was compared. Paper waste sludges with low and high ash content (8.5 and 46.7 wt.%) were converted under optimised conditions for temperature and pellet size to maximise both product yields and energy content. Comparison of the gross energy conversions, as a combination of the bio-oil/tarry phase and char (ECsum), revealed that the fast pyrolysis performance was between 18.5% and 20.1% higher for the low ash PWS, and 18.4% and 36.5% higher for high ash PWS, when compared to the slow and vacuum pyrolysis processes respectively. For both PWSs, this finding was mainly attributed to higher production of condensable organic compounds and lower water yields during FP. The low ash PWS chars, fast pyrolysis bio-oils and vacuum pyrolysis tarry phase products had high calorific values (∼18-23 MJ kg-1) making them promising for energy applications. Considering the low calorific values of the chars from alternative pyrolysis processes (∼4-7 MJ kg-1), the high ash PWS should rather be converted to fast pyrolysis bio-oil to maximise the recovery of usable energy products.

Advanced fibre gratings and their applications

This thesis describes a detailed study of advanced fibre grating devices using Bragg (FBG) and long-period (LPG) structures and their applications in optical communications and sensing. The major contributions presented in this thesis are summarised below. One of the most important contributions from the research work presented in this thesis is a systematic theoretical study of many distinguishing structures of fibre gratings. Starting from the Maxwell equations, the coupled-mode equations for both FBG and LPG were derived and the mode-overlap factor was analytically discussed. Computing simulation programmes utilising matrix transform method based on the models built upon the coupled-mode equations were developed, enabling simulations of spectral response in terms of reflectivity, bandwidth, sidelobes and dispersion of gratings of different structures including uniform and chirped, phase-shifted, Moiré, sampled Bragg gratings, phase-shifted and cascaded long-period gratings. Although the majority of these structures were modelled numerically, analytical expressions for some complex structures were developed with a clear physical picture. Several apodisation functions were proposed to improve sidelobe suppression, which guided effective production of practical devices for demanding applications. Fibre grating fabrication is the other major part involved in the Ph.D. programme. Both the holographic and scan-phase-mask methods were employed to fabricate Bragg and long-period gratings of standard and novel structures. Significant improvements were particularly made in the scan-phase-mask method to enable the arbitrarily tailoring of the spectral response of grating devices. Two specific techniques - slow-shifting and fast-dithering the phase-mask implemented by a computer controlled piezo - were developed to write high quality phase-shifted, sampled and apodised gratings. A large number of LabVIEW programmes were constructed to implement standard and novel fabrication techniques. In addition, some fundamental studies of grating growth in relating to the UV exposure and hydrogenation induced index were carried out. In particular, Type IIa gratings in non-hydrogenated B/Ge co-doped fibres and a re-generated grating in hydrogenated B/Ge fibre were investigated, showing a significant observation of thermal coefficient reduction. Optical sensing applications utilising fibre grating devices form the third major part of the research work presented in this thesis. Several experiments of novel sensing and sensing-demodulating were implemented. For the first time, an intensity and wavelength dual-coding interrogation technique was demonstrated showing significantly enhanced capacity of grating sensor multiplexing. Based on the mode-splitting measurement, instead of using conventional wavelength-shifting detection technique, successful demonstrations were also made for optical load and bend sensing of ultra-high sensitivity employing LPG structures. In addition, edge-filters and low-loss high-rejection bandpass filters of 50nm stop-band were fabricated for application in optical sensing and high-speed telecommunication systems

Elastic and inelastic scattering of fast neutrons in fusion reactor materials

In this work, the angular distributions for elastic and. inelastic scattering of fast neutrons in fusion .reactor materials have been studied. Lithium and lead material are likely to be common components of fusion reactor wall configuration design. The measurements were performed using an associated particle time-of- flight technique. The 14 and 14.44 Mev neutrons were produced by the T(d,n} 4He reaction with deuterons being accelerated in a 150kev SAMES type J accelerator at ASTON and in.the 3. Mev DYNAMITRON at the Joint Radiation Centre, Birmingham respectively. The associated alpha-particles and fast. neutrons were detected.by means of a plastic scintillator mounted on a fast focused photomultiplier tube. The samples used were extended flat plates of thicknesses up to 0.9 mean-free-path for Lithium and 1.562 mean-free-path for Lead. The differential elastic scattering cross-sections were measured for 14 Mev neutrons for various thicknesses of Lithium and Lead in the angular range from zero to; 90º. In addition, the angular distributions of elastically scattered 14,.44 Mev .neutrons from Lithium samples were studied in the same angular range. Inelastic scattering to the 4.63 Mev state in 7Li and the 2.6 Mev state, and 4.1 Mev state in 208Pb have:been :measured.The results are compared to ENDF/B-IV data files and to previous measurements. For the Lead samples the differential neutron scattering:cross-sections for discrete 3 Mev ranges and the angular distributions were measured. The increase in effective cross-section due to multiple scattering effects,as the sample thickness increased:was found to be predicted by the empirical .relation ....... A good fit to the exoerimental data was obtained using the universal constant............ The differential elastic scattering cross-section data for thin samples of Lithium and Lead were analyzed in terms of optical model calculations using the. computer code. RAROMP. Parameter search procedures produced good fits to the·cross-sections. For the case of thick samples of Lithium and Lead, the measured angular distributions of :the scattered neutrons were compared to the predictions of the continuous slowing down model.

A techno-economic comparison of power production by biomass fast pyrolysis with gasification and combustion

This paper presents an assessment of the technical and economic performance of thermal processes to generate electricity from a wood chip feedstock by combustion, gasification and fast pyrolysis. The scope of the work begins with the delivery of a wood chip feedstock at a conversion plant and ends with the supply of electricity to the grid, incorporating wood chip preparation, thermal conversion, and electricity generation in dual fuel diesel engines. Net generating capacities of 1–20 MWe are evaluated. The techno-economic assessment is achieved through the development of a suite of models that are combined to give cost and performance data for the integrated system. The models include feed pretreatment, combustion, atmospheric and pressure gasification, fast pyrolysis with pyrolysis liquid storage and transport (an optional step in de-coupled systems) and diesel engine or turbine power generation. The models calculate system efficiencies, capital costs and production costs. An identical methodology is applied in the development of all the models so that all of the results are directly comparable. The electricity production costs have been calculated for 10th plant systems, indicating the costs that are achievable in the medium term after the high initial costs associated with novel technologies have reduced. The costs converge at the larger scale with the mean electricity price paid in the EU by a large consumer, and there is therefore potential for fast pyrolysis and diesel engine systems to sell electricity directly to large consumers or for on-site generation. However, competition will be fierce at all capacities since electricity production costs vary only slightly between the four biomass to electricity systems that are evaluated. Systems de-coupling is one way that the fast pyrolysis and diesel engine system can distinguish itself from the other conversion technologies. Evaluations in this work show that situations requiring several remote generators are much better served by a large fast pyrolysis plant that supplies fuel to de-coupled diesel engines than by constructing an entire close-coupled system at each generating site. Another advantage of de-coupling is that the fast pyrolysis conversion step and the diesel engine generation step can operate independently, with intermediate storage of the fast pyrolysis liquid fuel, increasing overall reliability. Peak load or seasonal power requirements would also benefit from de-coupling since a small fast pyrolysis plant could operate continuously to produce fuel that is stored for use in the engine on demand. Current electricity production costs for a fast pyrolysis and diesel engine system are 0.091/kWh at 1 MWe when learning effects are included. These systems are handicapped by the typical characteristics of a novel technology: high capital cost, high labour, and low reliability. As such the more established combustion and steam cycle produces lower cost electricity under current conditions. The fast pyrolysis and diesel engine system is a low capital cost option but it also suffers from relatively low system efficiency particularly at high capacities. This low efficiency is the result of a low conversion efficiency of feed energy into the pyrolysis liquid, because of the energy in the char by-product. A sensitivity analysis has highlighted the high impact on electricity production costs of the fast pyrolysis liquids yield. The liquids yield should be set realistically during design, and it should be maintained in practice by careful attention to plant operation and feed quality. Another problem is the high power consumption during feedstock grinding. Efficiencies may be enhanced in ablative fast pyrolysis which can tolerate a chipped feedstock. This has yet to be demonstrated at commercial scale. In summary, the fast pyrolysis and diesel engine system has great potential to generate electricity at a profit in the long term, and at a lower cost than any other biomass to electricity system at small scale. This future viability can only be achieved through the construction of early plant that could, in the short term, be more expensive than the combustion alternative. Profitability in the short term can best be achieved by exploiting niches in the market place and specific features of fast pyrolysis. These include: •countries or regions with fiscal incentives for renewable energy such as premium electricity prices or capital grants; •locations with high electricity prices so that electricity can be sold direct to large consumers or generated on-site by companies who wish to reduce their consumption from the grid; •waste disposal opportunities where feedstocks can attract a gate fee rather than incur a cost; •the ability to store fast pyrolysis liquids as a buffer against shutdowns or as a fuel for peak-load generating plant; •de-coupling opportunities where a large, single pyrolysis plant supplies fuel to several small and remote generators; •small-scale combined heat and power opportunities; •sales of the excess char, although a market has yet to be established for this by-product; and •potential co-production of speciality chemicals and fuel for power generation in fast pyrolysis systems.

Systems biology approach to study permeability of paracetamol and its solid dispersion

Physiological changes that take place at cellular level are usually reflective of their level of gene expression. Different formulation excipients have an impact on physiological behavior of the exposed cells and in turn affect transporter genes, enterocyte-mediated metabolism and toxicity biomarkers. The aim of this study was to prepare solid dispersion of paracetamol and evaluate genetic changes that occur in Caco-2 cell lines during the permeability of paracetamol alone and paracetamol solid dispersion formulations. Paracetamol-PEG 8000 solid dispersion was prepared by melt fusion method and the formulation was characterised using differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Formulation of solid dispersion resulted in the conversion of crystalline drug into an amorphous form. Permeability studies showed that paracetamol absorption was higher from the solid dispersion formulation. DNA microarrays analysis was carried out in order to investigate the involvement of any efflux/uptake transporters in paracetamol or its solid dispersion permeability. Neither transporter carriers nor efflux proteins were found to be involved in the absorption of paracetamol or its PEG solid dispersion. Gene expression analysis established that paracetamol toxicity was potentially reduced upon formulation into solid dispersion when ATP binding cassette (ABC) and solute carrier transporter (SLC) genes were analyzed.

Pharmacologically induced and stimulus evoked rhythmic neuronal oscillatory activity in the primary motor cortex in vitro

Parkinson's disease (PD) is associated with enhanced synchronization of neuronal network activity in the beta (15-30 Hz) frequency band across several nuclei of the basal ganglia (BG). Deep brain stimulation of the subthalamic nucleus (STN) appears to reduce this pathological oscillation, thereby alleviating PD symptoms. However, direct stimulation of primary motor cortex (M1) has recently been shown to be effective in reducing symptoms in PD, suggesting a role for cortex in patterning pathological rhythms. Here, we examine the properties of M1 network oscillations in coronal slices taken from rat brain. Oscillations in the high beta frequency range (layer 5, 27.8 +/- 1.1 Hz, n=6) were elicited by co-application of the glutamate receptor agonist kainic acid (400 nM) and muscarinic receptor agonist carbachol (50 mu M). Dual extracellular recordings, local application of tetrodotoxin and recordings in M1 micro-sections indicate that the activity originates within deep layers V/VI. Beta oscillations were unaffected by specific AMPA receptor blockade, abolished by the GABA type A receptor (GABAAR) antagonist picrotoxin and the gap-junction blocker carbenoxolone, and modulated by pentobarbital and zolpidem indicating dependence on networks of GABAergic interneurons and electrical coupling. High frequency stimulation (HFS) at 125 Hz in superficial layers, designed to mimic transdural/transcranial stimulation, generated gamma oscillations in layers 11 and V (incidence 95%, 69.2 +/- 7.3 Hz, n=17) with very fast oscillatory components (VFO; 100-250 Hz). Stimulation at 4 Hz, however, preferentially promoted theta activity (incidence 62.5%, 5.1 +/- 0.6 Hz, n=15) that effected strong amplitude modulation of ongoing beta activity. Stimulation at 20 Hz evoked mixed theta and gamma responses. These data suggest that within M1, evoked theta, gamma and fast oscillations may coexist with and in some cases modulate pharmacologically induced beta oscillations.

Design of the low vision quality-of-life questionnaire (LVQOL) and measuring the outcome of low-vision rehabilitation

PURPOSE: To design and validate a vision-specific quality-of-life assessment tool to be used in a clinical setting to evaluate low-vision rehabilitation strategy and management. METHODS: Previous vision-related questionnaires were assessed by low-vision rehabilitation professionals and patients for relevance and coverage. The 74 items selected were pretested to ensure correct interpretation. One hundred and fifty patients with low vision completed the chosen questions on four occasions to allow the selection of the most appropriate items. The vision-specific quality of life of patients with low vision was compared with that of 70 age-matched and gender-matched patients with normal vision and before and after low-vision rehabilitation in 278 patients. RESULTS: Items that were unreliable, internally inconsistent, redundant, or not relevant were excluded, resulting in the 25-item Low Vision Quality-of-Life Questionnaire (LVQOL). Completion of the LVQOL results in a summed score between 0 (a low quality of life) and 125 (a high quality of life). The LVQOL has a high internal consistency (α = 0.88) and good reliability (0.72). The average LVQOL score for a population with low vision (60.9 ± 25.1) was significantly lower than the average score of those with normal vision (100.3 ± 20.8). Rehabilitation improved the LVQOL score of those with low vision by an average of 6.8 ± 15.6 (17%). CONCLUSIONS: The LVQOL was shown to be an internally consistent, reliable, and fast method for measuring the vision-specific quality of life of the visually impaired in a clinical setting. It is able to quantify the quality of life of those with low vision and is useful in determining the effects of low-vision rehabilitation. Copyright (C) 2000 Elsevier Science Inc.

A study of the scattering of fast neutrons in large samples

In the present work, the elastic scattering of fast neutrons from iron and concrete samples were studied at incident neutron energies of 14.0 and 14.4 Mev, using a neutron spectrometer based on the associated particle time-of-flight technique. These samples were chosen because of their importance in the design of fusion reactor shielding and construction. Using the S.A.M.E.S. accelerator and the 3 M v Dynamitron accelerator at the Radiation Centre, 14.0 and 14.4 Mev neutrons were produced by the T(d, n)4He reaction at incident deuteron energies of 140 keV and 900 keV mass III ions respectively. The time of origin of the neutron was determined by detecting the associated alpha particles. The samples used were extended flat plates of thicknesses up to 1.73 mean free paths for iron and 2.3 mean free paths for concrete. The associated alpha particles and fast neutrons were detected by means of a plastic scintillator mounted on a fast focused photomultiplier tube. The differential neutron elastic scattering cross-sections were measured for 14 Mev neutrons in various thicknesses of iron and concrete in the angular range from zero to 90°. In addition, the angular distributions of 14.4 Mev neutrons after passing through extended samples of iron were measured at several scattering angles in the same angular range. The measurements obtained for the thin sample of iron were compared with the results of Coon et al. The differential cross-sections for the thin iron sample were also analyzed on the optical model using the computer code RAROMP. For the concrete sample, the angular distribution of the thin sample was compared with the cross-sections calculated from the major constituent elements of concrete, and with the predicted values of the optical model for those elements. No published data could be found to compare with the results of the concrete differential cross-sections. In the case of thick samples of iron and concrete, the number of scattered neutrons were compared with a phenomological calculation based on the continuous slowing down model. The variation of measured cross-sections with sample thickness were found to follow the empirical relation σ = σ0 eαx. By using the universal constant "K", good fits were obtained to the experimental data. In parallel with the work at 14.0 and 14.4 Mev, an associated particle time-of-flight spectrometer was investigated which used the 2H(d,n)3He reaction for 3.02 Mev neutron energy at the incident deuteron energy of 1 Mev.

The characterisation and optimisation of modified herbaceous grasses for identifying pyrolisis-oil quality traits

The primary objective of this work is to relate the biomass fuel quality to fast pyrolysis-oil quality in order to identify key biomass traits which affect pyrolysis-oil stability. During storage the pyrolysis-oil becomes more viscous due to chemical and physical changes, as reactions and volatile losses occur due to aging. The reason for oil instability begins within the pyrolysis reactor during pyrolysis in which the biomass is rapidly heated in the absence of oxygen, producing free radical volatiles which are then quickly condensed to form the oil. The products formed do not reach thermodynamic equilibrium and in tum the products react with each other to try to achieve product stability. The first aim of this research was to develop and validate a rapid screening method for determining biomass lignin content in comparison to traditional, time consuming and hence costly wet chemical methods such as Klason. Lolium and Festuca grasses were selected to validate the screening method, as these grass genotypes exhibit a low range of Klason /Acid Digestible Fibre lignin contents. The screening methodology was based on the relationship between the lignin derived products from pyrolysis and the lignin content as determined by wet chemistry. The second aim of the research was to determine whether metals have an affect on fast pyrolysis products, and if any clear relationships can be deduced to aid research in feedstock selection for fast pyrolysis processing. It was found that alkali metals, particularly Na and K influence the rate and yield of degradation as well the char content. Pre-washing biomass with water can remove 70% of the total metals, and improve the pyrolysis product characteristics by increasing the organic yield, the temperature in which maximum liquid yield occurs and the proportion of higher molecular weight compounds within the pyrolysis-oil. The third aim identified these feedstock traits and relates them to the pyrolysis-oil quality and stability. It was found that the mineral matter was a key determinant on pyrolysis-oil yield compared to the proportion of lignin. However the higher molecular weight compounds present in the pyrolysis-oil are due to the lignin, and can cause instability within the pyrolysis-oil. The final aim was to investigate if energy crops can be enhanced by agronomical practices to produce a biomass quality which is attractive to the biomass conversion community, as well as giving a good yield to the farmers. It was found that the nitrogen/potassium chloride fertiliser treatments enhances Miscanthus qualities, by producing low ash, high volatiles yields with acceptable yields for farmers. The progress of senescence was measured in terms of biomass characteristics and fast pyrolysis product characteristics. The results obtained from this research are in strong agreement with published literature, and provides new information on quality traits for biomass which affects pyrolysis and pyrolysis-oils.

The effect of heat treatment on mechanical properties of pulsed Nd:YAG welded thin Ti6Al4V

Pulsed Nd:YAG has been adopted successfully in welding process of thin (0.7 mm) Ti6Al4V. Laser welding of such thin sheet requires a small focal spot, good laser beam quality and fast travel speed, since too much heat generation can cause distortion for thin sheet weld. The microstructures of Ti6Al4V were complex and strongly affected the mechanical properties. These structures include: a´ martensite, metastable ß, Widmanstätten, bimodal, lamellar and equiaxed microstructure. Bimodal and Widmanstätten structures exhibit a good-balance between strength and ductility. The microstructure of pulsed Nd:YAG welded Ti6Al4V was primarily a´ martensite, which showed the lowest ductility but not significantly high strength. A heat treatment at 950 followed by furnace cooling can transform the microstructure in the weld from a´ martensite structure into Widmanstätten structure.

Formulation and process engineering of freeze-dried orally disintegrating tablets

Orally disintegrating tablets (ODTs) which are also referred to as orodispersible and fast disintegrating tablets, are solid oral dosage forms which upon placing on the tongue, disperse/disintegrate rapidly before being swallowed as a suspension or solution. ODTs are therefore easier and more convenient to administer than conventional tablets and are particularly beneficial for paediatric and geriatric patients, who generally have difficulty swallowing their medication. The work presented in this thesis involved the formulation and process development of ODTs, prepared using freeze-drying. Gelatin is one of the principal excipients used in the formulation of freeze-dried ODTs. One of the studies presented in this thesis investigated the potential modification of the properties of this excipient, in order to improve the performance of the tablets. As gelatin is derived from animal sources, a number of ethical issues surround its use as an excipient in pharmaceutical preparations. This was one of the motivations, Methocel™ and Kollicoat® IR were evaluated as binders as alternative materials to gelatin. Polyox™ was also evaluated as a binder together with its potential uses as a viscosity increasing and mucoadhesive agent to increase the retention of tablets in the mouth to encourage pre-gastric absorption of active pharmaceutical ingredients (APIs). The in vitro oral retention of freeze-dried ODT formulations was one property which was assessed in a design of experiments – factorial design study, which was carried out to further understand the role that formulation excipients have on the properties of the tablets. Finally, the novel approach of incorporating polymeric nanoparticles in freeze-dried ODTs was investigated, to study if the release profile of APIs could be modified, which could improve their therapeutic effect. The results from these studies demonstrated that the properties of gelatin-based formulations can be modified by adjusting pH and ionic strength. Adjustment of formulation pH has shown to significantly reduce tablet disintegration time. Evaluating Methocel™, in particular low viscosity grades, and Kollicoat® IR as binders has shown that these polymers can form tablets of satisfactory hardness and disintegration time. Investigating Polyox™ as an excipient in freeze-dried ODT formulations revealed that low viscosity grades appear suitable as binders whilst higher viscosity grades could potentially be utilised as viscosity increasing and mucoadhesive agents. The design of experiments – factorial design study revealed the influence of individual excipients in a formulation mix on resultant tablet properties and in vitro oral retention of APIs. Novel methods have been developed, which allows the incorporation of polymeric nanoparticles in situ in freeze-dried ODT formulations, which allows the modification of the release profile of APIs.