AIM The aim of this study was to identify the immediate effects on cortical excitability and grip control of a short intervention of EMG-triggered neuromuscular electrical stimulation, compared to voluntary activation of the finger flexor muscles, in people with chronic stroke. STUDY DESIGN This experimental study used a within-subject design with experimental and control interventions. PARTICIPANTS Fifteen people with chronic stroke participated in the study. INTERVENTION Participants performed a simple force tracking task with or without EMG-triggered neuromuscular electrical stimulation of the finger flexor muscles. MAIN OUTCOME MEASURES Cortical excitability was measured by single and paired-pulse transcranial magnetic stimulation. Multi-digit grip control accuracy was measured during ramp and sine wave force tracking tasks. Maximal grip strength was measured before and after each intervention to monitor muscle fatigue. RESULTS No significant increases in cortico-motor excitability were found. Intracortical inhibition significantly increased following the EMG-triggered neuromuscular electrical stimulation intervention immediately post-intervention (t = 2.466, p = .036), and at 10 minutes post-intervention (t = 2.45, p = .04). Accuracy during one component of the force tracking tasks significantly improved (F(1, 14) = 4.701, p = .048), following both EMG-triggered neuromuscular electrical stimulation and voluntary activation interventions. Maximal grip strength reduced significantly following both interventions, after the assessment of cortical excitability (F(1, 8) = 9.197, p = .16), and grip control (F(1, 14) = 9.026, p = .009). CONCLUSIONS EMG-triggered neuromuscular electrical stimulation during short duration force tracking training does not increase cortical excitability in participants with chronic stroke. Short duration force tracking training both with and without EMG-triggered neuromuscular electrical stimulation leads to improvements in training-specific aspects of grip control in people with chronic stroke.

AIM The aim of this study was to identify the immediate effects on cortical excitability and grip control of a short intervention of EMG-triggered neuromuscular electrical stimulation, compared to voluntary activation of the finger flexor muscles, in people with chronic stroke. STUDY DESIGN This experimental study used a within-subject design with experimental and control interventions. PARTICIPANTS Fifteen people with chronic stroke participated in the study. INTERVENTION Participants performed a simple force tracking task with or without EMG-triggered neuromuscular electrical stimulation of the finger flexor muscles. MAIN OUTCOME MEASURES Cortical excitability was measured by single and paired-pulse transcranial magnetic stimulation. Multi-digit grip control accuracy was measured during ramp and sine wave force tracking tasks. Maximal grip strength was measured before and after each intervention to monitor muscle fatigue. RESULTS No significant increases in cortico-motor excitability were found. Intracortical inhibition significantly increased following the EMG-triggered neuromuscular electrical stimulation intervention immediately post-intervention (t = 2.466, p = .036), and at 10 minutes post-intervention (t = 2.45, p = .04). Accuracy during one component of the force tracking tasks significantly improved (F(1, 14) = 4.701, p = .048), following both EMG-triggered neuromuscular electrical stimulation and voluntary activation interventions. Maximal grip strength reduced significantly following both interventions, after the assessment of cortical excitability (F(1, 8) = 9.197, p = .16), and grip control (F(1, 14) = 9.026, p = .009). CONCLUSIONS EMG-triggered neuromuscular electrical stimulation during short duration force tracking training does not increase cortical excitability in participants with chronic stroke. Short duration force tracking training both with and without EMG-triggered neuromuscular electrical stimulation leads to improvements in training-specific aspects of grip control in people with chronic stroke.

The aim of this ethnographic study was to explore and describe the lay care (self-care) phenomenon in Thai culture. Spradley's (1979) ethnographic method was utilised to investigate the meaning of lay care, the lived experiences of 10 individuals who had suffered a stroke and their family caregivers in caring for the sick person at home.The meanings and perceptions of self-care from the individuals' and their families' perspectives, were explored, including the practices and cultural issues relating to care at home. The data collection was undertaken over a 10 month period in Songkla Province, southern Thailand. The major sources of data were the transcripts of semi-structured informal interviews, focus group discussions, field notes of participant observations and interviews with other individuals who were knowledgeable of health services and cultural issues relating to care and treatment in the community.Data analysis revealed a number of themes related to family relationships, and home and community care. These themes included the lived experience at both home and healing centres, experiences with change and loss after the stroke and coping with these, perceptions of care-receiving and caregiving, scope of the family's responsibilities in the caregiving role, caregiving burden, factors influencing the quality of care and the recipient's satisfaction with care. Other themes related to support and health services: Western and traditional medicine, social networks and religion. These themes were discussed from three perspectives: the individual, the family and community resources.The results of the study support the concept of interdependence of family members, and to a lesser extent their wider social network, in health and illness. Consequently the model of care developed from this study focuses on the family, with the family as a whole contributing to the ++ / well-being of its members through both the promotion of family members' health and the restoration of the health of the family with a sick member(s). Implications of this model of care were identified for nursing practice, education and research.

Diss. (sammanfattning) Uppsala : Univ., 2002. / Härtill 5 uppsatser.

Includes bibliographical references and index.

Thesis (Ph.D.)--University of Florida, 2004. / Typescript. Title from title page of source document. Document formatted into pages; contains 148 pages. Includes Vita. Includes bibliographical references.

Bakgrund: Stroke är den näst största orsaken till dödsfall och den tredje största orsaken till funktionshinder i världen. Sjuksköterskan är en viktig del i patientens vårdteam. Sjuksköterskor bör hjälpa patienter som insjuknat i stroke att finna mening samt övervinna sitt lidande, vilket kräver en god kommunikation mellan patient och sjuksköterska. Syfte: Belysa sjuksköterskors upplevelser och erfarenhet av att vårda patienter som insjuknat i stroke. Metod: Denna studie är en litteraturöversikt som grundar sig i 15 vetenskapliga artiklar. Artiklarna hittades i databaserna PubMed och Cinahl som sedan analyserades och resultatet från artiklarna delades in i kategorier och subkategorier. Resultat: Sjuksköterskor upplevde svårigheter med att samarbeta inom vårdteamet och arbetsförhållande samt bristande kompetens. Patienter som insjuknat i stroke och deras anhöriga hade stort behov av stöd och tid. Sjuksköterskor strävade efter att prestera sitt bästa samt ge den bästa omvårdnaden och rehabiliteringen som är möjligt. Diskussion: Förbättring av kommunikation krävs både inom teamet och till patienter som insjuknat i stroke för att vården ska bli bättre. Mer utbildning kring strokevård upplevdes nödvändigt då sjuksköterskor upplevde osäkerhet samt kunskaps- och kompetensbrist. Slutsats: Genom denna studie kan brister inom strokevården belysas och diskuteras i hälso-och sjukvården som skulle kunna leda till förändringar och förbättringar vilket gynnar vårdkvaliteten och sjuksköterskors arbetsmiljö och välbefinnande på arbetsplatsen. / <p>Godkännande datum: 2017-11-08</p>

Small vessel disease (SVD) accounts for approximately 25% of all strokes and 45% of all dementias. Although the small vessels cannot be visualised with conventional neuroimaging, the pathological changes in the cerebral white and deep grey matter secondary to SVD has been adopted as markers of SVD. These are best appreciated with magnetic resonance imaging (MRI) and includes recent small subcortical infarcts, white matter hyperintensity (WMH), lacunes, cerebral microbleeds and enlarged perivascular spaces (PVSs). There are however a number of outstanding questions regarding these surrogate neuroimaging markers of SVD and how these markers may influence clinical management. First, although a high burden of microbleeds have been associated with an increased risk of intracerebral haemorrhage (ICH) and possibly recurrent ischaemic stroke in patients with TIA or ischaemic stroke, how microbleeds should influence antithrombotic treatment use after TIA or ischaemic stroke remains uncertain. Second, the long-term prognostic implications of enlarged PVSs in patients with TIA or ischaemic stroke have not been studied. Third, although previous studies have shown possible ethnic differences in prevalence of microbleeds, whether there are any ethnic differences in prevalence of other neuroimaging markers of SVD remains unclear. Fourth, although a Total SVD Score was recently proposed to measure the global SVD burden, the prognostic value of this score in patients with TIA or ischaemic stroke has yet to be studied. Fifth, the relationships of long-term premorbid blood pressure with global SVD burden is unknown. Finally, the age and sex specific associations between renal impairment, carotid and cerebral pulsatility with burden of SVD has yet to be studied. The aim of my thesis was therefore to determine the clinical correlates, ethnic differences and long-term prognostic implications of a range of neuroimaging markers and global burden of SVD. I also aimed to determine the relationships of global SVD burden with long-term mean premorbid blood pressure, renal impairment and carotid pulsatiltiy. I have collected, collated and analysed clinical and neuroimaging data from two independent cohorts - the Oxford Vascular Study (OXVASC) and The University of Hong Kong (HKU). In particular I worked as one of the Clinical Research Fellows at OXVASC and was involved in regular recruitment, assessment and follow up of study patients. In OXVASC, 1080 predominantly Caucasians with TIA or ischaemic stroke who had a cerebral MRI performed at baseline was recruited during 2004 to 2014. I interpreted all these MRIs, specifically coding the burden of microbleeds, enlarged perivascular spaces and lacunes. I was involved in obtaining funding and developing the HKU cohort, which includes 1003 predominantly Chinese with ischaemic stroke recruited during 2008-2014 who had a cerebral MRI performed at baseline. I saw about 25% of the patients in the cohort and was involved in interpreting all of the MRIs of the cohort. All patients from both cohorts were followed-up regularly and adverse events including recurrent ischaemic stroke and ICH was determined. Presence and burden of periventricular and subcortical WMH, lacunes, microbleeds, basal ganglia and centrum semiovale PVSs was determined for all patients and the global burden of SVD estimated according to the Total SVD Score. There are several clinically relevant findings in this thesis. First, I have shown that in Caucasians and Chinese with ≥5 microbleeds, withholding antiplatelet drugs during the first year after TIA or ischaemic stroke may be inappropriate, especially early after TIA. However, the risk of ICH is likely to outweigh any benefit thereafter. Second, I have shown that TIA or ischaemic stroke patients with microbleeds on warfarin had an increased risk of subsequent ICH. However, this risk was not different from that of antiplatelet users with microbleeds. Third, I have shown that a high burden of MRI-visible basal ganglia PVSs is independently associated with an increased risk of recurrent ischaemic stroke, but not ICH. However, the prognostic value of MRI-visible centrum semiovale PVSs in the TIA or ischaemic stroke population is limited. Fourth, I demonstrated significant ethnic differences in underlying prevalence and burden of neuroimaging markers of SVD - Chinese had a greater prevalence of microbleeds, lacunes and subcortical WMH, whilst Caucasians had a greater prevalence of periventricular WMH and PVSs. Fifth, I validated the Total SVD Score and showed that the SVD Score is able to predict risk of recurrent ischaemic stroke and ICH in Caucasians and Chinese, but is unable to identify patients at high risk of ICH from those at high risk of recurrent ischaemic stroke. Sixth, I showed that mean premorbid blood pressure, especially diastolic blood pressure measurements taken 10-20 years prior to TIA or ischaemic stroke was most strongly associated with global SVD burden suggesting a latency effect of hypertension on the pathogenesis of SVD. Finally, I demonstrated age-specific associations between renal impairment, internal carotid artery pulsatility index and SVD burden.

The phenomenon whereby people suffering from an illness or disability seem to be unaware of their symptoms was termed anosognosia, by Joseph Babinksi in 1914 (Langer & Levine, 2014). Originally described as a specific inability to recognise or acknowledge left-sided hemiplegia after lesions to the right hemisphere of the brain, the term now incorporates unawareness of a range of post-stroke impairments, such as hemianopia (Bisiach, Vallar, Perani, Papagno & Berti, 1986), hemianaesthesia (Pia et al., 2014), aphasia (Cocchini, Gregg, Beschin, Dean & Della Sala, 2010) and unilateral neglect (Jehkonen, Ahonen, Dastidar, Laippala & Vilkki, 2000). Anosognosia has also been observed in association with several other disorders, including Alzheimer’s disease (Agnew & Morris, 1998) and traumatic brain injury (Prigatano, 2010a). While advances have been made in understanding anosognosia, there are still many contradictory findings in relation to the nature and expression of impaired self-awareness (Prigatano, 2010a), which are partly attributable to diverse methodological approaches. Furthermore, research into anosognosia frequently rests on the assumption that neurologically intact individuals have accurate insight into their own abilities, particularly in regard to motor skill. The experiments reported in this thesis highlight that this may be a false assumption. Through a series of interrelated studies, I demonstrate that the type of questions typically asked of anosognosic patients may be inappropriate to elicit the manifestations of chronic stage unawareness after a stroke, that underestimation may be just as prevalent as overestimation, and that healthy individuals are not always able to monitor whether their executed movements match their intended movements. Moreover, those with poorer motor skills are less able to judge movement successes and failures than their more skilled counterparts, suggesting a mechanism analogous to the anosognosia observed in clinical populations. Chapter 1 provides an overview of the main neuropsychological models that have been proposed to account for anosognosia for hemiplegia (AHP); unawareness in the context of other impairments is discussed in the introductions to individual chapters. Chapter 2 presents some background research investigating stroke clinicians’ knowledge of the lateralization of right hemisphere cognitive symptoms, and their judgements of the impact of selected symptoms on the lives of patients and caregivers. While the clinicians were equally able to identify cognitive symptoms associated with left or right brain damage, they were far more likely to misattribute symptoms to right brain damage, suggesting a lack of confidence in their knowledge of the cognitive functions of the right hemisphere. They also regarded anosognosia as having relatively low impact on the lives of patients and caregivers, in stark contrast with the highly negative impact reported in the literature (Jehkonen, Laihosalo & Kettunen, 2006a). Chapters 3 and 4 present two experimental studies investigating different facets of awareness in two groups of stroke patients. Chapter 3 reports the development and testing of a tool designed to measure chronic unawareness of functional difficulties, the Visual Analogue Test of Anosognosia for impairments in Activities of Daily Living (VATA-ADL), with preliminary data from a group of chronic stroke patients. Approximately one third of the patients exhibited mild or moderate levels of overestimation of their ability to carry out day-to-day activities. This contrasts with previous reports that anosognosia is rare in the chronic stages, a discrepancy that may be explained in part by the inappropriateness of the measures typically used to measure it. Overestimation was observed in both right-brain-damaged and left-brain-damaged patients, and was not associated with higher levels of cognitive impairment. The study reported in Chapter 4 examined whether acute stage stroke patients who under- or overestimated their motor skills, similarly under- or overestimated performance on cognitive tasks in the domains of language, memory and attention and executive function. Contrary to the many dissociations between unawareness of different impairment reported in the neuropsychological literature, this study found that patients classed as overestimators of motor ability were also overly optimistic about their cognitive abilities. Overestimators were more likely to have right hemisphere lesions, higher levels of general cognitive impairments, and specific deficits in attention and executive function. Furthermore, by including patients with a range of functional ability, this study revealed that participants were just as likely to underestimate as overestimate their abilities. This unique finding presents a challenge to anosognosia research, suggesting that there may be factors other than neurological damage that predispose stroke patients to over- or under-estimate their abilities and that a baseline of accurate self-insight among control populations cannot be assumed. Chapter 5 reports three different experiments conducted with younger and older, neurologically healthy adults. Using a target-directed reaching task, these experiments investigated whether the participants’ ability to monitor the success of their movements, on a trial by trial basis, depended upon their motor skill level, and whether participants with lower skill were inclined to overestimate their ability, in line with a famous observation from cognitive psychology that people who perform worst in a given task tend to be unaware of how poorly they are performing (Kruger and Dunning, 1999). Overall, the results demonstrated an association between higher accuracy levels and faster movement times, and better ability to monitor success and failure. To my knowledge, this represents that first evidence of a relationship between motor performance ability and self-monitoring ability in healthy individuals, highlighting that some of the mechanisms underpinning anosognosia may also be evident in neurologically intact populations. However, contrary to the findings from cognitive psychology, poor performance was not associated with a specific bias toward overestimation. A similar relationship between task performance and self-monitoring ability was also observed for a visual memory task. Chapter 6 discusses the implications of the results of the clinical and self-monitoring studies for neuropsychological models of anosognosia, particularly those based on motor planning and control, and considers potential ways forward for research in this field.

Despite challenges with poor emissions and fuel economy, gasoline two stroke engines continue to be developed for a number of applications. The primary reasons for the choice of a gasoline two stroke engine includes its low cost, mechanical simplicity and high specific power output. Some applications for the gasoline two stroke engine include small capacity motorcycles and scooters, off road recreational vehicles, hand held power tools and unmanned aerial vehicles. New technologies, which are already mature in four stroke engines, are now being applied to two stroke engines. Such technologies include direct fuel injection, electronic engine management and exhaust gas after treatment. To implement these new technologies computation models are being continuously developed to improve the design process of engines. Multi-dimensional computational fluid dynamics modelling is now commonly applied to engine research and development, it is a powerful tool that can give great insight into the thermofluid working of an engine. Multi-dimensional tools are however computationally expensive and quasi-dimensional modelling methods are often better suited for the analysis of an engine, for example in transient engine simulation. This thesis reports the development of a new quasi-dimensional combustion model for a loop scavenged two stroke engine. The model differs from other quasi-dimensional models available in the literature as it accounts for a bulk motion of the flame front due to the tumble motion created by the loop scavenge process. In this study the tumble motion is modelled as an ellipsoid vortex and the size of the vortex is defined by the combustion chamber height and a limiting elliptical aspect ratio. The limiting aspect ratio has been observed in experimental square piston compression machines and optical engines. The new model also accounts for a wrinkled flame brush thickness and its effects on the interaction between flame front and combustion chamber. The new combustion model has been validated against experimental engine tests in which the flame front propagation was measured using ionization probes. The probes were able determine the flame front shape, the bulk movement of the flame front due to tumble and also the wrinkled flame brush thickness.