Some electromyogram (EMG) signals include information from limb functions and have been used to control the movement of prosthesis. To develop practical malfunction myoelectically controlled prosthesis using an EMG signal, the best identification model for limb functions has to be established. The thesis presents an investigation and comparison between different identification methods for limb functions based on the use of statistical processing, neural networks, and fuzzy methods. The research focused on the establishment of robust identification models of limb functions in order to obtain objective comparison results. Therefore, some factors affecting the robustness of an identification model were investigated in detail, such as, how to choose the length of signal, extract and select the optimal features, and establish and select a model. The analysis of the power spectrum and eigenvalues of the autocorrelation matric of a surface EMG signal was used to decide the length of signals. A selection method of optimal features was presented through the analysis of the advantage and disadvantage of the Jeffries-Matusita distance measurement and the cluster separation index (CSI). The confidence interval of the recognition rate of a model was used to measure the robustness of the model and decide the size of the training and test sets. The different identification models were established using the optimal features using different pattern recognition methods, based on statistical, neural network and fuzzy methods. During ther modelling process of neural networks, the Bayesian technique was used to avoid the model tending to the idiosyncrasies of the test set. During the fuzzy logic modelling process, methods for extracting fuzzy rules were investigated to establish a good fuzzy identification model for limb functions. In the selection process of model, different selection methods of models were used according to the practical situation. Finally, noise analyses were completed to assess the sensitivity of some methods to noise. The comparisons were made between different identification methods based on the identification results, their confidence inv=tervals and their modelling methods. The best processing methods were concluded

The purpose of this thesis was to show a relationship between muscle strength and allergic reactions. Clinics have for many years relied on what have become traditional methods for testing for allergic reactions. These include such tests as the Patch test and the Skin-Prick test. Both these tests cause discomfort and irritation to sensitive patients. The historical development of allergies is outlined, showing that scientists and clinicians in the late 18th and early 19th century were aware of certain reactions which people showed to apparently normal non-reactive foods. The development of methods of diagnosing allergies such as the elimination diet, which dates back to approx 1940, are surveyed. Current practices are also studied with the use of photographs. The reaction of the skin to modern day testing practices is shown. In some cases these reactions are quite violent. The Applied Kinesiology Test is examined as a universally used test which when carried out by an experienced Kinesiologist can give a true but highly subjective response to a patients allergic condition. A system has been developed based on the relationship between muscle strength and allergies, the components of this system were readily available at little cost. Once a basic system was built it was possible to perform trials on patients at an established allergy clinic. With the aid of a data printer it became possible to prove first graphically and second statistically that there was a statistically valid relationship between the measured muscle strength and allergies. The conclusion shows that the final version of the operating system is capable of equaling the performance of an experienced Kinesiologist, showing its results both digitally and graphically rather than subjectively. The various deductions and recommendations which are detailed, point towards a readily marketable device which could represent a potential break through in modern allergy testing. The system will also open the way for clinicians to make an objective assessment of the relationship between muscle strength and allergic sensitivity via further research.

No description available.

Nanotechnology products have huge potential to be a part of the developments in various fields, including functional materials, electronics and medicine. Using nanomaterials in medical applications has been successful for disease diagnosis and drug delivery systems. One of the safest and most versatile nanomaterials utilized for medical purposes are iron oxide nanomaterials. This thesis presents the synthesis, coating and targeting vector modification of iron oxide materials for several biomedical applications including multimodal imaging and cancer cell targeting. Iron oxide nanorods (NRDs) were produced and coated with silica shells as well as other surface modifying molecules including azamacrocycles (DO3A) and polyethylene glycol chains (PEG) which were attached in a one pot reaction. The presence of PEG on the NRDs surface gave improved suspension stability over a wide range of salt concentrations and pH values. Radiolabelling of the NRDs was demonstrated with the positron emitting radioisotope ⁶⁸Ga. The use of nanorods as magnetic resonance imaging (MRI) contrast agents gave a two-fold increase in T2 relaxivity (180 s⁻¹) compared to previous work using spherical nanoparticles. The ⁶⁸Ga labelled NRD constructs show high radiochemical stability against transferrin challenge over a 3 h incubation period. An in vivo bio-distribution study was carried out by intravenously injecting a CD1 nude female mice with 2 mg of (NRDs-PEG), then multimodal imaging analysis was performed using MRI and positron emission tomography (PET) imaging. The NRDs with sizes between 100 to 200 nm showed rapid accumulation in the liver after 5 min due to uptake by macrophages and Kupffer cells as part of reticuloendothelial system, and a small quantity accumulated in the lung and spleen. It was also observed that in the MRI T2 weighted image, the liver is significantly darker than the T1 weighted imaging which confirms the sample accumulation. The multimodal images proved that the radiolabelled NRDs were stable in vivo on the timescale of the imaging study. Iron oxide nanoparticles (IONPs) were functionalised for targeting cancer cells. The IONPs were conjugated to a chemokine receptor targeting vector and the targeting properties were tested in vitro using Jurkat cancer cells with flow cytometry in an antibody competition assay. The NPs showed 100% inhibition of the anti-CXCR4 antibody binding in this assay.

Experiments were performed using a modification of the technique developed by Spanner and Prebble 1962 to monitor the translocation of tracers along the petiole of Nymohoides peltata. Three tracers were used, Br and Na and at least three experiments were performed using each isotope. A very complete record of tracer distribution in time and space was obtained for each isotope. Computer simulation of translocation was developed based on a physical model consisting of a centrally located conducting channel in which a mass flow occurs and a surrounding non-conducting ground tissue. Reversible lateral exchange takes place between these two. The simulation is characterised by an inputfunction and three dimensionless parameters, V, R and K which are related to the velocities of longitudinal flow and reversible lateral leakage and which can be varied with both time and distance. The simulation is possessed of considerable versatility and in this way has many advantages over existing mathematical models. The information it provides is useful in its own right and suggests that the importance accorded the linear nature of the semi-logarithmic profiles in the past is unwarrented. In association with the above simulation a simple direct search optimisation programme was developed based on the least squares criterion to match the simulation to the experimental data. It was found that an acceptable match to the experiments could only be obtained if the time course accumulation of activity in the root-stock was reduced by an arbitrary factor. Although this part of the work failed in its main objective of obtaining estimates of the translocation parameters, it at least suggested a way in which they may be estimated and is encouraging for future work.

No description available.

The use of aptamers acting within novel biosensors as molecular recognition elements is well documented with a wide variety of techniques being adapted to take advantage of the benefits of oligonucleotide detection. A continuing barrier to the commercial use of ssDNA or RNA aptamers remains the lack of a high-throughput system that confers reliable selection and description of suitable species. Here we describe simple methodologies that utilise fusion proteins, modified affinity chromatography, HPLC, and, nanopore assays, along with other techniques to isolate novel aptamers to well-characterised proteins. These methods have yielded novel aptamers to the HsdR, and HsdS subunits of type I restrictionmodification system EcoR124I and to the human rhinovirus 3C protease, along with an enriched libraries for nitrotyrosine. In addition to the isolation of novel aptamer species, methods for the characterisation of the binding capabilities of candidate aptamers are presented. The techniques of SPR, EMSA, and dot blotting are evaluated and utilised in the appraisal of the novel aptamer sequences.

Traditional myoelectricity-based systems have inherent limitations and weaknesses to control dexterous prosthesis. The gap lies not in the methodologies that already extensively researched, but the means of signal extraction from the forearm. This thesis has explored and successfully tackled the practical control problems of dexterous prostheses using Sonomyography (SMG). Two hypotheses were made and supported by relevant literature to highlight the type of contraction that relevant to the amputees. The relevance of Fatigue-less Maximum Isotonic Contraction (FLMIC) phase is highlighted in SMG with experimental data. A novel wearable and portable SMG capturing system is presented with performances on a par with myoelectric methods. The Quasi-radial construction of the ultrasound transducer array allows reading A-mode signals from both anterior and posterior compartments of the forearm. The arrays comprised of transducers which are purpose designed to meet the requirements. The experiments with amputee and healthy subjects revealed that comparable gesture recognition accuracies can be achieved. Proportional control of prosthesis is a noted problem. Since the majority of morphological changes occur in isotonic or dynamic region, the tension produced by the muscle is low. Contrary to sEMG, where it requires a significant motor unit activation, a low level muscle activation is enough to provide proportional control using sonomyography. This phenomenon is investigated in this thesis. The cross correlation method has been employed to recognize gestures between test and training sets. The experimental results demonstrated the ability to utilize the system in underwater without significantly compromising the performance. The experiment also demonstrated that the effectiveness of oil based coupling medium in such conditions. In this study a novel wearable ultrasound hardware is presented with evidence to prove its comparable performances with myoelectric systems.

Cyanides enter the environment through both natural and man-made sources. Natural sources include cyanogenesis by bacteria, fungi and plants. A number of cyanide catabolising microorganisms have also been reported in literature. This is the first reported instance of cyanide catabolism in Trichoderma harzianum. Four strains of T. harzianum, one of T. pseudokoningii were evaluated. An investigation was made into the occurrence and distribution of the cyanide catabolising enzymes. Three enzymes, cyanide hydratase, beta-cyanoalanine synthase and rhodanese, were studied. All the strains showed a high capacity to degrade cyanide via both the cyanide hydratase and rhodanese pathways, beta-cyanoalanine synthase activity, however, was not detected in any of the selected strains. In the studies on the kinetic characterization of the rhodanese enzyme, a broad pH optimum of 8.5 - 10.5 was obtained for all the strains and a broad temperature optimum of 35 - 55 °C was also observed. The KmCN and Vmax values ranged from 7-16 mM and from 0.069 - 0.093 betamoles. Min-1. mg protein-1, respectively, between the selected strains of Trichoderma. Strong evidence of cyanide biodegradation and co-metabolism emerged from studies with flask cultures where glucose was provided as a co-substrate. The rate of degradation of 2000 ppm CIST was enhanced almost three times in the presence of glucose. Plant microcosm studies carried out using pea and wheat seeds too gave further corroboration of the cyanide degrading and plant growth promotion capabilities of Trichoderma. Microcosms set-up with cyanide at 50 or 100 ppm CN, in the presence of Trichoderma, showed germination of both pea and wheat seeds. There was no seed germination in any of the controls in the absence of Trichoderma inoculation.

The objective of prostheses and of dynamic orthoses is to provide restorative function to anatomical joints of the upper or lower limb that are either absent or physiologically compromised. This study considers the volitional demands of upper limb function and the periodic requirements of the lower limb during gait. Control strategies using discrete magneto-transducers to measure normal residual physiological activities which predict intended joint positions of dysfunctional or absent joints in the lower or upper limb, have been investigated and tested by experiment. The restoration of ankle dorsiflexion in hemiplegics with drop foot using functional electrical stimulation (FES) has been investigated. FES is traditionally controlled using a pressure switch in the heel of the shoe switching the stimulation on only when the foot is not weight bearing. However functional and cosmetic constraints of this method of control do not make it universally acceptable. A novel FES controller using a magneto-transducer to measure the cyclic variation of angular velocity of the leg through the knee has been developed. Experimentation with this controller showed that reliable switching of FES during successive gait cycles was possible in some patients with a hemiplegic drop foot. Most powered prosthetic prehensors and wrist units are controlled using the myoelectric activity of muscles. Such prostheses however have no intrinsic relationship between the position of the prosthetic prehensor and wrist unit and hence a degree of conscious effort in their control is required. A powered prosthetic prehensor and wrist unit has been developed using magneto-transducers which sense the myokinemetric activity of muscles dedicated to grasping and which measure forearm rotation. Reliable volitional control of the position of prosthetic prehension and wrist rotator has been demonstrated over several cycles of grasping and wrist rotation.