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The Global ETD Search service is a free service for researchers
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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.
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Showing 1 to 9 of 9 (0.112 seconds)| 1 |
Role of antibodies to glutamic acid decarboxylase in type 1 diabetes:relation to other autoantibodies, HLA risk markers and clinical characteristicsSabbah, E. (Emad) 05 May 2000 (has links)
Abstract
The purpose of this research was to assess the role of antibodies
to glutamic acid decarboxylase (GAD) in children with newly diagnosed
type 1 diabetes in relation to other disease-associated autoantibodies
and HLA-defined genetic disease susceptibility, to evaluate the
role of GAD antibodies (GADA) in relation to clinical characteristics
at the diagnosis of type 1 diabetes and to compare the frequency
and levels of GADA between adult and childhood onset type 1 diabetes.The
study population comprised altogether 999 children and adolescents
with type 1 diabetes, 100 affected adult subjects and more than
370 non-diabetic controls. GADA were measured with a liquid radioligand
assay, and a similar assay was used for the analysis of antibodies
to the islet antigen 2 (IA-2) molecule. Islet cell antibodies (ICA)
were determined with conventional immunofluorescence and insulin
autoantibodies (IAA) with a liquid phase radioimmunoassay either in
a tube or a plate format (microassay).
GADA were detected at diagnosis in 68 to 73% of the
children and adolescents with type 1 diabetes. GADA were more frequent
in girls and in those older than 10 years of age at clinical disease manifestation.
Subjects testing positive for GADA had higher levels of ICA and
IAA than those negative for GADA. Multiple antibodies ( 2) were
observed more often in girls and in children under the age of 5
years.
Children with the HLA DR3/non-DR4 phenotype had the
highest GADA levels, significantly higher than those seen in children
with the DR4/non-DR3 combination. The highest prevalence
of multiple autoantibodies was seen in subjects heterozygous for
DR3/4. When studying HLA DQB1 genotypes those with the
DQB1*02/y (y = other than *0302)
genotype had the highest GADA levels as expected since DQB1*02
and DR3 are in strong linkage disease equilibrium. The same group
had the lowest frequency of multiple antibodies among the children
younger than 10 years of age.Patients diagnosed with type 1 diabetes
before the age of 20 had a higher frequency of all four autoantibodies
analysed than those presenting with clinical disease after the age
of 20. The proportion of subjects testing negative for all four
antibodies was substantially higher among adults than in those under
the age of 20. The smallest age-related difference in antibody frequencies
was observed for GADA, and the GADA-positive adult patients had
on an average about three times higher antibody levels than the
GADA-positive children.
No association was observed between positivity for GADA and
the degree of metabolic decompensation at the clinical presentation
of type 1 diabetes. No significant differences were either seen
between the subjects who tested positive for GADA at diagnosis and
those who were negative in serum C-peptide concentrations, metabolic
control or exogenous insulin requirement over the first 2 years
of observation. The proportion of children in clinical remission
was, however, lower among GADA-positive subjects than in GADA-negative
patients at 18 months after the clinical manifestation. Positivity
for multiple antibodies was associated with accelerated beta-cell
destruction and increased exogenous insulin requirements over the
2-year observation period.
The observations that GADA are related to female gender, older
age and the HLA-DR3/ DQB1*02 haplotype suggest
that a strong humoral immune response to GAD may reflect a propensity
to general autoimmunity rather than specific beta-cell destruction.
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DENTAL AND SKELETAL OUTCOMES FOR CLASS II SURGICAL-ORTHODONTIC TREATMENT: A COMPARISON BETWEEN EXPERIENCED AND NOVICE CLINICIANSPotts, Brittany L.W. 27 August 2009 (has links)
No description available.
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Assessment and risk prediction in patients with aortic stenosis : insights from cardiovascular magnetic resonanceChin, Calvin Woon Loong January 2015 (has links)
BACKGROUND Aortic stenosis affects not only the valve but also the myocardium. In response to the increased afterload, left ventricular hypertrophy initially occurs as a compensatory response to maintain wall stress and cardiac output but ultimately, decompensation and heart failure ensues. The transition from adaptation to decompensation is driven by myocyte death and myocardial fibrosis. The aims of the thesis are to investigate cardiovascular magnetic resonance assessment of disease severity and myocardial fibrosis, and explore its relationship with other biomarkers of disease activity and clinical outcome in patients with aortic stenosis. METHODS AND RESULTS The conventional assessment of aortic stenosis relies heavily on two-dimensional and Doppler echocardiography but there are inherent limitations in echocardiography that can affect the severity classification. I demonstrated that cardiovascular magnetic resonance offered a more accurate estimation of left ventricular volumes and mass, and excellent myocardial characterization. Indeed, inaccurate stroke volume estimation by Doppler echocardiography and inconsistent thresholds in current guidelines accounted for more than 40% of patients with discordant small-area, lowgradient aortic stenosis. These data may explain the variable prognosis reported in this unique group of patients, and argue for more accurate assessment of borderline cases with cardiovascular magnetic resonance. Late gadolinium enhancement imaging detects focal areas of established myocardial fibrosis. In many conditions, including aortic stenosis, a more diffuse form of fibrosis predominates, which is potentially reversible and not readily identified by late gadolinium enhancement. Recently several myocardial T1 mapping approaches have been developed to quantify diffuse fibrosis. Using a standardized and systematic approach, I compared several commonly used T1 mapping techniques and identified that extracellular volume had the best profile (reproducibility and discriminatory potential) for the identification of diffuse fibrosis in patients with aortic stenosis. Cardiac troponin is a structural protein present in the cardiac myocytes. Recent advances in assay technology have substantially improved sensitivity, allowing quantification of troponin concentrations with a high degree of precision in everyone. In more than 250 patients with aortic stenosis, I demonstrated that cardiac troponin I concentrations were independently associated with markers of left ventricular decompensation (hypertrophy and fibrosis) and predicted clinical outcome in patients with aortic stenosis. This suggests that myocardial fibrosis detected by cardiovascular magnetic resonance is consequent on myocardial injury secondary to left ventricular decompensation. Left ventricular hypertrophy with strain pattern on a 12-lead electrocardiogram is associated with poor outcome in patients with aortic stenosis, but the mechanism of this electrocardiographic pattern has not been described. In more than 300 patients with aortic stenosis, I demonstrated that these characteristic repolarization abnormalities were a highly specific marker of focal mid-wall myocardial fibrosis (specificity of 99% and sensitivity of 54%). Moreover, the prognostic value of this electrocardiographic pattern was again confirmed with markedly worse long-term outcomes in these patients. CONCLUSION I have demonstrated that cardiovascular magnetic resonance can assist in the assessment of disease severity in patients with aortic stenosis and discordant echocardiographic findings. Moreover, I have validated the assessment of diffuse myocardial fibrosis, as well as, demonstrated the close association between myocardial fibrosis and biomarkers of myocardial injury and electrocardiographic strain pattern that predicted an adverse outcome in patients with aortic stenosis.
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Microanomia e valores humanos: contribuiÃÃes para compreensÃo do comportamento antissocial / Microanomie and human values: contributions to the comprehension of the antisocial behaviorGuilherme Sobreira Lopes 13 March 2015 (has links)
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / Anomia à um estado patolÃgico da estrutura social caracterizado pela ausÃncia ou enfraquecimento das normas. Em nÃvel individual, à o estado de desequilÃbrio valorativo referente à priorizaÃÃo de valores pessoais frente a valores sociais. Neste sentido, um construto psicolÃgico parece estar especialmente associado à anomia: os valores humanos. A presente dissertaÃÃo teve por objetivo avaliar as bases valorativas da anomia e suas relaÃÃes com os comportamentos antissociais. Para tanto, realizaram-se dois estudos. O Estudo I tem como objetivo avaliar a relaÃÃo entre os desequilÃbrios valorativos de baixa congruÃncia e aspectos demogrÃficos. Participaram do estudo 1147 estudantes de ensino fundamental, mÃdio e universitÃrio da cidade de JoÃo Pessoa â PB, com idades entre 10 e 45 anos (m = 16,1; dp = 4,5, sendo 64,8% entre 11 e 17 anos), sendo a maioria feminina (60,1%), catÃlica (60,6%) e da rede pÃblica (52,1%). Estes responderam ao QuestionÃrio de Valores BÃsicos â QVB e a questÃes demogrÃficas. Os resultados indicaram que a microanomia independe da classe social, mas varia conforme a gÃnero e a faixa etÃria. Apresentam-se questÃes teÃricas e metodolÃgicas que podem explicar os dados. O Estudo II objetivou testar a hipÃtese de congruÃncia e de compatibilidade dos valores humanos e avaliar a microanomia em amostras da populaÃÃo geral e encarcerados. Para tanto, contarà com duas amostras. A primeira contou com 994 indivÃduos da populaÃÃo geral, com idades entre 14 e 56 anos (m = 21,7; dp = 6,3, sendo 49,8% entre 18 e 25 anos), majoritariamente feminina (50,6%), heterossexual (87,6%) e catÃlica (49,5%). A segunda contou com 762 encarcerados com idades entre 19 e 66 anos (m = 29,6; dp = 8,5, sendo 49,5% entre 19 e 27 anos), majoritariamente masculina (71,9%), heterossexual (87,7%), catÃlica (42,1%). A primeira amostra respondeu ao QVB e a questÃes demogrÃficas. A amostra de encarcerados respondeu, alÃm do QVB, a 73 itens que abordaram diferentes facetas da vida dos detentos, a saber: histÃrico prisional, perfil educacional, perfil laboral, estrutura familiar, experiÃncia no sistema carcerÃrio, indicadores de saÃde mental e, por fim, questÃes demogrÃficas. Os resultados confirmaram as hipÃteses de congruÃncia e compatibilidade. Por outro lado, as hipÃteses relacionadas à comparaÃÃo dos nÃveis de microanomia em indivÃduos da populaÃÃo geral e encarcerados foram refutadas. PropÃem-se possÃveis explicaÃÃes teÃricas e metodolÃgicas. O presente estudo traz contribuiÃÃes para a compreensÃo do comportamento antissocial, possibilitando o desenvolvimento de modelos teÃricos. / Anomie is a condition of the social structure characterized by the absence or weakening of social norms. At the individual level, is the state of decompensation or imbalance on the prioritization of personal values front to social values. In this sense, a psychological construct appears to be particularly associated with anomie: human values. This dissertation aimed to evaluate the value basis of anomie and its relations with antisocial behavior. Therefore, two studies were performed. Study I aimed to evaluate the relationship between value decompensation between low congruence values and demographics. Participated of this study 1147 students of primary and secondary school and college city of JoÃo Pessoa - PB, aged between 10 to 45 years (m = 16.1, SD = 4.5, and 64.8% between 11 and 17 years ) with majority women (60.1%), Catholic (60.6%) and from public schools (52.1%). They answered the Basic Values Questionnaire - QVB and demographic issues. The application of the instruments occurred in schools and universities. The results indicated that microanomie does not depend of social class, but varies according to gender and age group. Study II aimed to test the hypothesis of consistency and compatibility of human values and evaluate the microanomie in samples of general population and imprisoned. To do so, two samples were considered. The first included 994 individuals from the general population, aged between 14 to 56 years (m = 21.7, SD = 6.3, and 49.8% between 18 and 25 years), mostly female (50.6%), heterosexual (87.6%) and Catholic (49.5%). The second included 762 prisoners aged between 19 to 66 years (m = 29.6, SD = 8.5, and 49.5% between 19 and 27 years), predominantly male (71.9%), heterosexual (87 7%) and Catholic (42.1%). The first sample responded to the QVB and demographic issues. The sample of incarcerated answered the QVB and 73 items that addressed different facets of their lives, namely: prison history, educational profile, employment profile, family structure, experiences in the prison system, mental health indicators and demographic questions. The results confirmed the hypothesis of consistency and compatibility. On the other hand, the assumptions related to the comparison of microanomie levels in the general population and prisoners were refuted. This study brings contributions to the understanding of antisocial behavior and to the development of theoretical models.
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Machine learning applications in Intensive Care UnitSheikhalishahi, Seyedmostafa 28 April 2022 (has links)
The rapid digitalization of the healthcare domain in recent years highlighted the need for advanced predictive methods particularly based upon deep learning methods. Deep learning methods which are capable of dealing with time- series data have recently emerged in various fields such as natural language processing, machine translation, and the Intensive Care Unit (ICU). The recent applications of deep learning in ICU have increasingly received attention, and it has shown promising results for different clinical tasks; however, there is still a need for the benchmark models as far as a handful of public datasets are available in ICU. In this thesis, a novel benchmark model of four clinical tasks on a multi-center publicly available dataset is presented; we employed deep learning models to predict clinical studies. We believe this benchmark model can facilitate and accelerate the research in ICU by allowing other researchers to build on top of it. Moreover, we investigated the effectiveness of the proposed method to predict the risk of delirium in the varying observation and prediction windows, the variable ranking is provided to ease the implementation of a screening tool for helping caregivers at the bedside. Ultimately, an attention-based interpretable neural network is proposed to predict the outcome and rank the most influential variables in the model predictions’ outcome. Our experimental findings show the effectiveness of the proposed approaches in improving the application of deep learning models in daily ICU practice.
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Microanomia e valores humanos: contribuições para compreensão do comportamento antissocial / Microanomie and human values: contributions to the comprehension of the antisocial behaviorLOPES, Guilherme Sobreira January 2015 (has links)
LOPES, Guilherme Sobreira. Microanomia e valores humanos: contribuições para compreensão do comportamento antissocial. 2015. 103f. – Dissertação (Mestrado) – Universidade Federal do Ceará, Programa de Pós-graduação em Psicologia, Fortaleza (CE), 2015. / Submitted by Márcia Araújo (marcia_m_bezerra@yahoo.com.br) on 2015-05-04T12:20:50Z
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Previous issue date: 2015 / Anomie is a condition of the social structure characterized by the absence or weakening of social norms. At the individual level, is the state of decompensation or imbalance on the prioritization of personal values front to social values. In this sense, a psychological construct appears to be particularly associated with anomie: human values. This dissertation aimed to evaluate the value basis of anomie and its relations with antisocial behavior. Therefore, two studies were performed. Study I aimed to evaluate the relationship between value decompensation between low congruence values and demographics. Participated of this study 1147 students of primary and secondary school and college city of João Pessoa - PB, aged between 10 to 45 years (m = 16.1, SD = 4.5, and 64.8% between 11 and 17 years ) with majority women (60.1%), Catholic (60.6%) and from public schools (52.1%). They answered the Basic Values Questionnaire - QVB and demographic issues. The application of the instruments occurred in schools and universities. The results indicated that microanomie does not depend of social class, but varies according to gender and age group. Study II aimed to test the hypothesis of consistency and compatibility of human values and evaluate the microanomie in samples of general population and imprisoned. To do so, two samples were considered. The first included 994 individuals from the general population, aged between 14 to 56 years (m = 21.7, SD = 6.3, and 49.8% between 18 and 25 years), mostly female (50.6%), heterosexual (87.6%) and Catholic (49.5%). The second included 762 prisoners aged between 19 to 66 years (m = 29.6, SD = 8.5, and 49.5% between 19 and 27 years), predominantly male (71.9%), heterosexual (87 7%) and Catholic (42.1%). The first sample responded to the QVB and demographic issues. The sample of incarcerated answered the QVB and 73 items that addressed different facets of their lives, namely: prison history, educational profile, employment profile, family structure, experiences in the prison system, mental health indicators and demographic questions. The results confirmed the hypothesis of consistency and compatibility. On the other hand, the assumptions related to the comparison of microanomie levels in the general population and prisoners were refuted. This study brings contributions to the understanding of antisocial behavior and to the development of theoretical models. / Anomia é um estado patológico da estrutura social caracterizado pela ausência ou enfraquecimento das normas. Em nível individual, é o estado de desequilíbrio valorativo referente à priorização de valores pessoais frente a valores sociais. Neste sentido, um construto psicológico parece estar especialmente associado à anomia: os valores humanos. A presente dissertação teve por objetivo avaliar as bases valorativas da anomia e suas relações com os comportamentos antissociais. Para tanto, realizaram-se dois estudos. O Estudo I tem como objetivo avaliar a relação entre os desequilíbrios valorativos de baixa congruência e aspectos demográficos. Participaram do estudo 1147 estudantes de ensino fundamental, médio e universitário da cidade de João Pessoa – PB, com idades entre 10 e 45 anos (m = 16,1; dp = 4,5, sendo 64,8% entre 11 e 17 anos), sendo a maioria feminina (60,1%), católica (60,6%) e da rede pública (52,1%). Estes responderam ao Questionário de Valores Básicos – QVB e a questões demográficas. Os resultados indicaram que a microanomia independe da classe social, mas varia conforme a gênero e a faixa etária. Apresentam-se questões teóricas e metodológicas que podem explicar os dados. O Estudo II objetivou testar a hipótese de congruência e de compatibilidade dos valores humanos e avaliar a microanomia em amostras da população geral e encarcerados. Para tanto, contará com duas amostras. A primeira contou com 994 indivíduos da população geral, com idades entre 14 e 56 anos (m = 21,7; dp = 6,3, sendo 49,8% entre 18 e 25 anos), majoritariamente feminina (50,6%), heterossexual (87,6%) e católica (49,5%). A segunda contou com 762 encarcerados com idades entre 19 e 66 anos (m = 29,6; dp = 8,5, sendo 49,5% entre 19 e 27 anos), majoritariamente masculina (71,9%), heterossexual (87,7%), católica (42,1%). A primeira amostra respondeu ao QVB e a questões demográficas. A amostra de encarcerados respondeu, além do QVB, a 73 itens que abordaram diferentes facetas da vida dos detentos, a saber: histórico prisional, perfil educacional, perfil laboral, estrutura familiar, experiência no sistema carcerário, indicadores de saúde mental e, por fim. , questões demográficas. Os resultados confirmaram as hipóteses de congruência e compatibilidade. Por outro lado, as hipóteses relacionadas à comparação dos níveis de microanomia em indivíduos da população geral e encarcerados foram refutadas. Propõem-se possíveis explicações teóricas e metodológicas. O presente estudo traz contribuições para a compreensão do comportamento antissocial, possibilitando o desenvolvimento de modelos teóricos.
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Identification of early cardiac decompensation and the management of intraaortic balloon counterpulsation weaningLewis, Peter Andrew January 2007 (has links)
Intraaortic balloon counterpulsation (IABP) is the most widely used mechanical support in the assistance of a failing heart.1 Despite extensive research in this field no experimental or clinical studies have been undertaken to evaluate the most effective manner to wean IABP.2 The research reported in this thesis examines early recognition of cardiac decompensation and the management of IABP weaning. Conducted in three phases, the aim of this research programme was to determine the best manner by which to wean IABP. Phase 1 utilised a comparative descriptive design to examine IABP practice at a single cardiothoracic tertiary referral hospital. The majority of data collection was prospective, however, the required sample size saw inclusion of some retrospective data. This single centre data were than compared with an international registry to contrast IABP management and outcome. Phase 2 utilised a questionnaire survey to audit all Australasian intensive care units. Survey results were combined and statistically analysed to describe Australasian IABP management, weaning and outcome. Phase 3 utilised a quasi-experimental, one-group, posttest-only design to clinically validate a tool designed to monitor a patient's cardiac function - the 'cardiac decompensation tool'. Phase 1 saw data collected for 669 IABP insertions over an 11 year period at a single Australian hospital. This cohort was compared against the 38,606 patient dataset of The Benchmark Counterpulsation Outcomes Registry. Australian IABP practice saw later application of the device in a higher acuity patient. Australian practice demonstrated a prejudice toward intraoperative use (34.2% versus 16.6%; p=< 0.0001) and an aversion to catheter laboratory support (10.6% versus 19%; p=< 0.0001). Australian mortality while slightly higher, remained comparable (22% versus 20.8%; p=ns). Phase 2 response rate was 60%. The most common Australasian method of IABP support withdrawal was ratio reduction only (61%). Units with a documented weaning policy were less likely to require balloon reinsertion or pharmacologic escalation following IABP removal (p=0.06). Indicators most likely to demonstrate a patient's readiness for IABP weaning were blood pressure (92%), heart rate (76%) and wedge pressure (59%). Phase 3 revealed cardiac decompensation tool scores to increase immediately prior to a treatment escalation (p=0.022) and decrease immediately following this escalation in therapy (p=0.0096). There was also some indication of decreasing scores prior to treatment minimisation (p=0.005). Tool scores demonstrated a corresponding treatment fluctuation up to three hours prior to the treatment intervention. With Phase 1 and 2 revealing many aspects of IABP practice to vary, the need for some direction regarding weaning is evident. Timely recognition of cardiac decompensation during IABP weaning allows an opportunity for the earlier escalation of treatment and consequent provision of increased cardiac support. Application of the Phase 3 cardiac decompensation tool can only assist in ensuring the best manner by which to support IABP weaning.
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Analýza provozu trakční napájecí stanice / Hybrid AC/DC,AC/AC substation operation analysisLakomý, Marek January 2014 (has links)
The work analyzes the operation of hybrid substations. The first chapter provides an analysis of domestic traction systems and describes in detail specific station. The next chapter follows the first in a way in which obtained parameters are converted to parameters suitable for the simulation program and presents its results. The third chapter discusses the serial communication used in one switchgear and about voltage regulator that controls one high voltage field. The last chapter verifies the simulation results obtained from the second chapter with real measurement and direct comparison is also included.
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Action in Chronic Fatigue Syndrome: an Enactive Psycho-phenomenological and Semiotic Analysis of Thirty New Zealand Women's Experiences of Suffering and RecoveryHart, M J Alexandra January 2010 (has links)
This research into Chronic Fatigue Syndrome (CFS) presents the results of 60 first-person psycho-phenomenological interviews with 30 New Zealand women. The participants were recruited from the Canterbury and Wellington regions, 10 had recovered. Taking a non-dual, non-reductive embodied approach, the phenomenological data was analysed semiotically, using a graph-theoretical cluster analysis to elucidate the large number of resulting categories, and interpreted through the enactive approach to cognitive science.
The initial result of the analysis is a comprehensive exploration of the experience of CFS which develops subject-specific categories of experience and explores the relation of the illness to universal categories of experience, including self, ‘energy’, action, and being-able-to-do.
Transformations of the self surrounding being-able-to-do and not-being-able-to-do were shown to elucidate the illness process.
It is proposed that the concept ‘energy’ in the participants’ discourse is equivalent to the Mahayana Buddhist concept of ‘contact’. This characterises CFS as a breakdown of contact. Narrative content from the recovered interviewees reflects a reestablishment of contact.
The hypothesis that CFS is a disorder of action is investigated in detail.
A general model for the phenomenology and functional architecture of action is proposed. This model is a recursive loop involving felt meaning, contact, action, and perception and appears to be phenomenologically supported.
It is proposed that the CFS illness process is a dynamical decompensation of the subject’s action loop caused by a breakdown in the process of contact.
On this basis, a new interpretation of neurological findings in relation to CFS becomes possible. A neurological phenomenon that correlates with the illness and involves a brain region that has a similar structure to the action model’s recursive loop is identified in previous research results and compared with the action model and the results of this research. This correspondence may identify the brain regions involved in the illness process, which may provide an objective diagnostic test for the condition and approaches to treatment.
The implications of this model for cognitive science and CFS should be investigated through neurophenomenological research since the model stands to shed considerable light on the nature of consciousness, contact and agency.
Phenomenologically based treatments are proposed, along with suggestions for future research on CFS. The research may clarify the diagnostic criteria for CFS and guide management and treatment programmes, particularly multidimensional and interdisciplinary approaches.
Category theory is proposed as a foundation for a mathematisation of phenomenology.
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