• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 221
  • 156
  • 148
  • 108
  • 31
  • 7
  • 3
  • 2
  • 1
  • 1
  • 1
  • Tagged with
  • 3286
  • 734
  • 224
  • 163
  • 146
  • 90
  • 83
  • 74
  • 61
  • 57
  • 56
  • 55
  • 54
  • 54
  • 53
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Inspiratory muscle training in a non-clinical population

Caine, M. P. January 1999 (has links)
Several studies have demonstrated that the respiratory muscles of normal adults can be specifically trained using a range of stimuli. However, the effect that respiratory muscle training has upon whole body exercise performance remains equivocal. Furthermore, the effectiveness of pressure threshold inspiratory muscle training (IMT) has yet to be appraised in non-clinical groups. Thus, the purpose of the present thesis was to establish the effects of IMT upon exercise performance in endurance trained individuals. To this end, a number of intermediate objectives were achieved; these included design and manufacture of a suitable IMT device and elucidation of an appropriate training regime. IMT was shown to enhance high-intensity sub-maximal cycling time to exhaustion following a four week intervention. Although gas exchange and ventilatory parameters remained unchanged, blood lactate concentration and ratings of perceived exertion were attenuated significantly following the intervention. Whilst the present thesis did not examine the aetiology underlying the ergogenic properties of IMT, it is reasonable to suggest that the physiological and psychological consequences of increased inspiratory muscle performance are functionally relevant in the context of exercise. A closer examination of potential mechanisms remains the focus for the future research if these phenomena are to be explained.
32

Elbow joint prosthesis design : biomechanical aspects

Nicol, A. C. January 1977 (has links)
A three-dimensional biomechanical analysis of elbow joint function is presented. Eating, dressing, pulling a heavy object and assisted standing from the seated position were investigated for healthy males in the age group 21 -25 years. Three cine cameras recorded the motion of specially designed markers taped to the upper limb and the forces transmitted between the hand and the environment were measured using a versatile force transducer. Muscle activity was recorded efectromyographically. A simplified model of the anatomical structures of the elbow joint was formulated and four computer programs were developed for the subsequent calculation of muscle, ligament and joint forces. Calculations showed that during the eating and dressing activities, compressive loads of 300 N were acting on the trochlear notch and in the other activities, the joint forces maximum values were 2000 N. Using several of the results from the theoretical analysis, a set of design criteria was established in connection with the development of a new elbow prosthesis. A detailed study of the geometry of the articular suifaces of the elbow was undertaken and a large series of X-rays was measured in order to determine the geometrical configuration of the distal humerus and the proximal ulna. Chapter 9 contains a full report on the design study and some of the more important aspects of the prototype prosthesis are discussed.
33

Investigation of photoplethysmography and arterial blood oxygen saturation during artificially induced peripheral hypoperfusion utilising multimode photometric sensors

Shafique, Muhammad January 2011 (has links)
No description available.
34

3D electrospun bundles of polycaprolactone for tendon regeneration

Bosworth, Lucy A. January 2009 (has links)
Tendon damage, both traumatic and degenerative, results in extensive morbidity in man and also in animals, such as racehorses. This is due to the inferior quality of scar tissue produced in response to tendon damage, which is biomechanically and biochemically weaker than the original tissue. This research has investigated the fabrication of a temporary tendon scaffold for surgical implantation into damaged tendons to facilitate superior repair. Tendons are a highly fibrous tissue, which has necessitated the production of a scaffold capable of recreating this complex hierarchical structure. The potential for electrospinning to produce fibres with dimensions similar to the extracellular matrix of natural tissues has led to its utilisation for the purpose of creating a tendon scaffold. Polycaprolactone was the selected material for scaffold composition due to its bioresorbability over long time periods coupled with its low toxicity in vivo and FDA approval. To establish the optimum parameters for producing fibres of appropriate dimensions, investigations focused on the use of different solvents, polymer molecular weight and parameters of the electrospinning process. The studies concluded that acetone and high molecular weight polymer (80,000 Mn) at a concentration of 10 % w/v was the optimal polymer/solvent solution. Fibres with diameters <1 urn were produced with the following electrospinning parameters; flow rate 0.05 mllmin, voltage 20 kV and needle-tip to collector distance> 10 cm. Fibre production was controlled using different collector methods. Random networks were collected on stationary plates, whilst aligned fibres were collected on mandrels rotating at an optimised speed. In order to mimic the hierarchical bundle structure observed within the Achilles tendon, 3D bundles of electrospun fibres were developed from four different techniques, each of which was associated with advantages and disadvantages. 3D bundles formed by collection from the edge (3 mm) of a fine rotating mandrel (500 RPM) were selected for all further investigations due to their uniformity and reproducibility, although these demonstrated slightly lower mechanical properties compared to two other bundle fabrication techniques. The mechanical properties of 3D bundles were significantly superior compared to 2D aligned fibrous mats. Biodegradation studies showed that 3D bundles degrade at a lesser rate compared to PCL solvent cast films. Bundles were biocompatible with tenocytes over a two-week in vitro study. Cells demonstrated interaction, proliferation and synthesis of extracellular matrix containing collagen. A pilot in vivo study - whereby the 3D bundle was surgically implanted into the Achilles of a murine model - assessed the efficacy of the scaffold over a three-week period. Mice returned to normal ambulation within 48 hrs and all mice survived until harvest. At three weeks the bundle was observed to be fully integrated into the tendon with visible new tissue formation. It is envisaged that with further development this may lead to production of an off-the-shelf scaffold appropriate for clinical application.
35

Preparation and characterisation of carbonate hydroxyapatite

Merry, John January 2000 (has links)
No description available.
36

Characterisation of hydroxyapatite for direct manufacture of bone implants using CADCAM techniques

Chelule, Kenneth Lang'at January 2002 (has links)
No description available.
37

Electromyographic analysis of hand muscle activity during mechanically perturbed rhythmic tasks

Redmond, Niamh M. January 2001 (has links)
No description available.
38

Theoretical study of brain biomechanics via poroelastic theory and the finite element method

Pena, Alonso January 1996 (has links)
No description available.
39

Studies on the activation and inactivation of cell movement

Lefford, Frances January 1963 (has links)
No description available.
40

The control of powered artificial limbs

Hall, Michael John January 1967 (has links)
No description available.

Page generated in 0.0348 seconds