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  • 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.
201

Development of an Upper Limb Robotic Device for Stroke Rehabilitation

Lu, Elaine Chen 14 December 2011 (has links)
Stroke is the major cause of permanent adult disability worldwide. Often stroke affects the motor control of the upper limb, leading to difficulties in performing activities of daily living. Many hours are spent in resource-intensive therapy to regain functionality of the upper limb. In order to decrease the burden to therapists and increase access to rehabilitation, an upper limb rehabilitation robotic device was developed. Observations from therapists and an international survey of stroke therapists were conducted to understand general requirements of an upper limb rehabilitation device. These requirements were the basis of the mechanical design portion of the prototype. The prototype was evaluated with stroke therapists in a focus group. Although more iterations of design, testing and evaluation are needed, this project is a step in developing a lower cost, portable device to increase access to upper limb stroke rehabilitation.
202

Upper gradients and Sobolev spaces on metric spaces

Färm, David January 2006 (has links)
The Laplace equation and the related p-Laplace equation are closely associated with Sobolev spaces. During the last 15 years people have been exploring the possibility of solving partial differential equations in general metric spaces by generalizing the concept of Sobolev spaces. One such generalization is the Newtonian space where one uses upper gradients to compensate for the lack of a derivative. All papers on this topic are written for an audience of fellow researchers and people with graduate level mathematical skills. In this thesis we give an introduction to the Newtonian spaces accessible also for senior undergraduate students with only basic knowledge of functional analysis. We also give an introduction to the tools needed to deal with the Newtonian spaces. This includes measure theory and curves in general metric spaces. Many of the properties of ordinary Sobolev spaces also apply in the generalized setting of the Newtonian spaces. This thesis includes proofs of the fact that the Newtonian spaces are Banach spaces and that under mild additional assumptions Lipschitz functions are dense there. To make them more accessible, the proofs have been extended with comments and details previously omitted. Examples are given to illustrate new concepts. This thesis also includes my own result on the capacity associated with Newtonian spaces. This is the theorem that if a set has p-capacity zero, then the capacity of that set is zero for all smaller values of p.
203

Development of an Upper Limb Robotic Device for Stroke Rehabilitation

Lu, Elaine Chen 14 December 2011 (has links)
Stroke is the major cause of permanent adult disability worldwide. Often stroke affects the motor control of the upper limb, leading to difficulties in performing activities of daily living. Many hours are spent in resource-intensive therapy to regain functionality of the upper limb. In order to decrease the burden to therapists and increase access to rehabilitation, an upper limb rehabilitation robotic device was developed. Observations from therapists and an international survey of stroke therapists were conducted to understand general requirements of an upper limb rehabilitation device. These requirements were the basis of the mechanical design portion of the prototype. The prototype was evaluated with stroke therapists in a focus group. Although more iterations of design, testing and evaluation are needed, this project is a step in developing a lower cost, portable device to increase access to upper limb stroke rehabilitation.
204

The Graded Redfined Assessment of Strength, Senssibility and Prehension (GRASSP): Development of the Scoring Approach, Evaluation of Psychometric Properties and the Relationship of Upper Limb Impairment to Function

Kalsi-Ryan, Sukhvinder 31 August 2011 (has links)
Upper limb function is important for individuals with tetraplegia because upper limb function supports global function for these individuals. As a result, a great deal of time and effort has been devoted to the restoration of upper limb function. Appropriate outcome measures that can be used to characterize the neurological status of the upper limb have been one of the current barriers in substantiating the efficacy of interventions. Techniques and protocols to evaluate changes in upper limb neurological status have not been applied to the SCI population adequately. The objectives of this thesis were to develop a measure; which is called the Graded Redefined Assessment of Strength Sensibility and Prehension (GRASSP). Development of the scoring approach, testing for reliability and construct validity, and determining impairment and function relationships specific to the upper limb neurological were established. The GRASSP is a clinical measure of upper limb impairment which incorporates the construct of “sensorimotor upper limb function”; comprised of three domains which include five subtests. The GRASSP was designed to capture information on upper limb neurological impairment for individuals with tetraplegia. The GRASSP defines neurological status with numerical values, which represent the deficits in a predictive pattern, is reliable and valid as an assessment technique, and the scores can be used to determine relationships between impairment and functional capability of the upper limb. The GRASSP is recommended for use in the very early acute phases after injury to approximately one year post injury. Use of the GRASSP is recommended when a change in neurological status is being assessed.
205

The West Indian Mission to West Africa: The Rio Pongas Mission, 1850-1963

Gibba, Bakary 09 January 2012 (has links)
This thesis investigates the efforts of the West Indian Church to establish and run a fascinating Mission in an area of West Africa already influenced by Islam or traditional religion. It focuses mainly on the Pongas Mission’s efforts to spread the Gospel but also discusses its missionary hierarchy during the formative years in the Pongas Country between 1855 and 1863, and the period between 1863 and 1873, when efforts were made to consolidate the Mission under black control and supervision. Between 1873 and 1900 when more Sierra Leonean assistants were hired, relations between them and African-descended West Indian missionaries, as well as between these missionaries and their Eurafrican host chiefs, deteriorated. More efforts were made to consolidate the Pongas Mission amidst greater financial difficulties and increased French influence and restrictive measures against it between 1860 and 1935. These followed an earlier prejudiced policy in the mission that was strongly influenced by the hierarchical nature of nineteenth-century Barbadian society, which was abandoned only after successive deaths and resignations of white superintendents and the demonstrated ability of black pastors to independently run the Mission. Instrumentalism aided the conversion process and the increased flow of converts threatened both the traditional belief systems and social order of the Pongas Country, resulting in confrontation between the Mission and traditional religion worshippers, while the lack of more legitimate trade in the Pongas Country and allegations of black missionaries’ illicit sexual relations and illegal trading caused the downfall of John Henry A. Duport, the Mission’s first black Head Missionary. In the late 1800s, efforts to establish a self-supporting, self-generating, and self-propagating church together with initiatives toward African agency in the Pongas Country failed. However, it was French activities and eventual consolidation of their interests in the Pongas Country from 1890 and their demand that Mission schools teach in French, together with successful recruiting of Mission students by the Roman Catholics and Muslim clerics in Guinea, that finally crippled it. Thus, by 1935 when the Gambia-Pongas Bishopric was established in the hope of rescuing the Mission, this gender-biased Christian enterprise in West Africa was already a spent force.
206

Design of an Adaptive System for Upper-limb Stroke Rehabilitation

Kan, Patricia Wai Ling 24 February 2009 (has links)
Stroke is the primary cause of adult disability. To support this large population in recovery, robotic technologies are being developed to assist in the delivery of rehabilitation. A partially observable Markov decision process (POMDP) system was designed for a rehabilitation robotic device that guides stroke patients through an upper-limb reaching task. The performance of the POMDP system was evaluated by comparing the decisions made by the POMDP system with those of a human therapist. Overall, the therapist agreed with the POMDP decisions approximately 65% of the time. The therapist thought the POMDP decisions were believable and could envision this system being used in both the clinic and home. The patient would use this system as the primary method of rehabilitation. Limitations of the current system have been identified which require improvement in future research stages. This research has shown that POMDPs have promising potential to facilitate upper extremity rehabilitation.
207

Biomedical and Psychosocial Factors Associated with Pain and Disability after Peripheral Nerve Injury

Novak, Christine 22 February 2011 (has links)
The main objective of my dissertation was to evaluate the biomedical and psychosocial factors associated with pain and disability in patients following traumatic upper extremity nerve injuries. This was approached by conducting 3 studies. The first study surveyed peripheral nerve surgeons regarding the assessment of pain in patients with nerve injury. The results showed that only 52% of surgeons always evaluate pain in patients referred for motor/sensory dysfunction. Pain assessment frequently includes verbal response and assessment of psychosocial factors is infrequent. The second study was a retrospective review to assess disability, as measured by the Disabilities of the Arm, Shoulder and Hand (DASH), in patients with chronic nerve injury. Results showed substantial disability (mean DASH 52 + 22) and a significantly lower health status (p < 0.001) compared with well-established norms. In the regression model, the factors associated with the DASH (R2 = 44.5%) were pain, older age and nerve injured. The third study was a cross-sectional evaluation of the biomedical and psychosocial factors associated with pain and disability after upper extremity nerve injury in 158 patients. DASH scores were significantly higher in patients with workers’ compensation or litigation (p = 0.03), brachial plexus injuries (p < 0.001) and unemployed patients (p < 0.001). In the multivariable regression analysis, the final model explained 52.7% of the variance with these predictors; pain intensity (Beta = .230, p = 0.006), nerve injured (Beta = -.220, p = 0.000), time since injury (Beta = -.198, p = 0.002), pain catastrophizing (Beta = .192, p = 0.025), age (Beta = .187, p = 0.002), work status (Beta = .179, p = 0.008), cold sensitivity (Beta = .171, p = 0.015), depression score (Beta = .133, p = 0.066), workers’ compensation/litigation (Beta = .116, p = 0.049) and gender (Beta = -.104, p = 0.09). Future investigation regarding treatments of the factors that are associated with disability and chronic pain will assist to improve health related quality of life in patients with traumatic nerve injury.
208

The Graded Redfined Assessment of Strength, Senssibility and Prehension (GRASSP): Development of the Scoring Approach, Evaluation of Psychometric Properties and the Relationship of Upper Limb Impairment to Function

Kalsi-Ryan, Sukhvinder 31 August 2011 (has links)
Upper limb function is important for individuals with tetraplegia because upper limb function supports global function for these individuals. As a result, a great deal of time and effort has been devoted to the restoration of upper limb function. Appropriate outcome measures that can be used to characterize the neurological status of the upper limb have been one of the current barriers in substantiating the efficacy of interventions. Techniques and protocols to evaluate changes in upper limb neurological status have not been applied to the SCI population adequately. The objectives of this thesis were to develop a measure; which is called the Graded Redefined Assessment of Strength Sensibility and Prehension (GRASSP). Development of the scoring approach, testing for reliability and construct validity, and determining impairment and function relationships specific to the upper limb neurological were established. The GRASSP is a clinical measure of upper limb impairment which incorporates the construct of “sensorimotor upper limb function”; comprised of three domains which include five subtests. The GRASSP was designed to capture information on upper limb neurological impairment for individuals with tetraplegia. The GRASSP defines neurological status with numerical values, which represent the deficits in a predictive pattern, is reliable and valid as an assessment technique, and the scores can be used to determine relationships between impairment and functional capability of the upper limb. The GRASSP is recommended for use in the very early acute phases after injury to approximately one year post injury. Use of the GRASSP is recommended when a change in neurological status is being assessed.
209

Movement-induced motor cortical excitability changes of upper limb representations during voluntary contraction of the contralateral limb: A TMS investigation of interhemispheric interactions

Goddard, Meaghan Elizabeth 02 September 2008 (has links)
Humans possess the ability to generate an incredible degree of complex, highly skilled, and coordinated movements. Although much is known about the anatomical and physiological components of upper limb movement, the exact means by which these different areas coordinate is still far from understood. The ability to perform symmetrical, bimanual tasks with ease suggest a default coupling between mirror motor regions – a default coupling that is perceptible in unilateral movements. During intended unimanual movement in the upper limbs, bilateral changes to motor cortex output occur. The purpose of this study was to investigate the neural underpinnings of these bilateral changes and investigate the involvement of intracortical inhibitory circuits. Previous studies have shown that transcallosal connections between cortical representations of the intrinsic muscles of the hands are relatively sparser than the more proximal muscles of the upper limbs. It was hypothesized that differential responses in overall motor output or intracortical inhibition to ipsilateral muscle activation between the FDI and ECR could infer the involvement of transcallosal pathways; although interhemispheric transfer was not directly investigated in this thesis. Two studies used focal transcranial magnetic stimulation (TMS), specifically paired-pulse protocols, to investigate changes in short-interval intracortical inhibition (SICI) and long-interval intracortical inhibition (LICI) in response to contraction of contralateral homologous muscle groups to the inactive test muscle. Also, the response to activation of a non-homologous, but spatially close, muscle was investigated. Lastly, two muscle groups were investigated, a distal, intrinsic muscle of the hand (first dorsal interosseous) and a relatively more proximal muscle of the upper limb (extensor carpi radialis). These studies revealed that at low levels of force generation, unilateral isometric contractions facilitate ipsilateral mirror motor representations and reduce local GABA¬A receptor mediated inhibition. Notably, while similar facilitation occurred in both the distal and proximal effectors, decreases in SICI were much more robust in the ECR. Findings from this thesis provides insight into the neural mechanisms governing bilateral changes with unilateral movement and is important in the guiding the focus of future research.
210

Movement-induced motor cortical excitability changes of upper limb representations during voluntary contraction of the contralateral limb: A TMS investigation of interhemispheric interactions

Goddard, Meaghan Elizabeth 02 September 2008 (has links)
Humans possess the ability to generate an incredible degree of complex, highly skilled, and coordinated movements. Although much is known about the anatomical and physiological components of upper limb movement, the exact means by which these different areas coordinate is still far from understood. The ability to perform symmetrical, bimanual tasks with ease suggest a default coupling between mirror motor regions – a default coupling that is perceptible in unilateral movements. During intended unimanual movement in the upper limbs, bilateral changes to motor cortex output occur. The purpose of this study was to investigate the neural underpinnings of these bilateral changes and investigate the involvement of intracortical inhibitory circuits. Previous studies have shown that transcallosal connections between cortical representations of the intrinsic muscles of the hands are relatively sparser than the more proximal muscles of the upper limbs. It was hypothesized that differential responses in overall motor output or intracortical inhibition to ipsilateral muscle activation between the FDI and ECR could infer the involvement of transcallosal pathways; although interhemispheric transfer was not directly investigated in this thesis. Two studies used focal transcranial magnetic stimulation (TMS), specifically paired-pulse protocols, to investigate changes in short-interval intracortical inhibition (SICI) and long-interval intracortical inhibition (LICI) in response to contraction of contralateral homologous muscle groups to the inactive test muscle. Also, the response to activation of a non-homologous, but spatially close, muscle was investigated. Lastly, two muscle groups were investigated, a distal, intrinsic muscle of the hand (first dorsal interosseous) and a relatively more proximal muscle of the upper limb (extensor carpi radialis). These studies revealed that at low levels of force generation, unilateral isometric contractions facilitate ipsilateral mirror motor representations and reduce local GABA¬A receptor mediated inhibition. Notably, while similar facilitation occurred in both the distal and proximal effectors, decreases in SICI were much more robust in the ECR. Findings from this thesis provides insight into the neural mechanisms governing bilateral changes with unilateral movement and is important in the guiding the focus of future research.

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