Detection of Optimal Models in Parameter Space with Support Vector Machines

The paper proposes an approach aimed at detecting optimal model parameter combinations to achieve the most representative description of uncertainty in the model performance. A classification problem is posed to find the regions of good fitting models according to the values of a cost function. Support Vector Machine (SVM) classification in the parameter space is applied to decide if a forward model simulation is to be computed for a particular generated model. SVM is particularly designed to tackle classification problems in high-dimensional space in a non-parametric and non-linear way. SVM decision boundaries determine the regions that are subject to the largest uncertainty in the cost function classification, and, therefore, provide guidelines for further iterative exploration of the model space. The proposed approach is illustrated by a synthetic example of fluid flow through porous media, which features highly variable response due to the parameter values' combination.

Free Flows, Limited Diversification: Explaining the Fall and Rise of Stock Market Correlations, 1890-2001

Using a new dataset on capital account openness, we investigate why equity return correlations changed over the last century. Based on a new, long-run dataset on capital account regulations in a group of 16 countries over the period 1890-2001, we show that correlations increase as financial markets are liberalized. These findings are robust to controlling for both the Forbes-Rigobon bias and global averages in equity return correlations. We test the robustness of our conclusions, and show that greater synchronization of fundamentals is not the main cause of increasing correlations. These results imply that the home bias puzzle may be smaller than traditionally claimed.

Morse Fall Scale: tradução e adaptação transcultural para a língua portuguesa

Estudo realizado com o objetivo de traduzir e adaptar a Morse Fall Scale da língua inglesa para a portuguesa. Foi realizado em sete etapas: autorização pela autora da escala; tradução para o português do Brasil; avaliação e estruturação da escala traduzida; tradução reversa para o inglês; avaliação e validação da escala pelo comitê de especialistas; avaliação da clareza dos itens e definições operacionais por 45 profissionais e avaliação da concordância entre avaliadores e confiabilidade da reprodutibilidade, quanto aos dados referentes à avaliação de 90 pacientes, por quatro avaliadores/juízes. Quanto à clareza da escala, as proporções foram consideradas muito satisfatórias, com intervalo de confiança entre 73% a 100% na opção muito claro. Quanto à concordância das respostas, os resultados apresentaram coeficientes Kappa em torno de 0,80 ou superiores. Concluiu-se que o processo de adaptação da escala foi bem sucedido, indicando que seu uso é apropriado para a população de pacientes brasileiros hospitalizados.

Human Sciences Matters, Fall 2006

A newsletter for alumni and friends of the Iowa State University College of Human Sciences.

Postoperative delirium. Part 2: detection, prevention and treatment.

To target pharmacological prevention, instruments giving an approximation of an individual patient's risk of developing postoperative delirium are available. In view of the variable clinical presentation, identifying patients in whom prophylaxis has failed (that is, who develop delirium) remains a challenge. Several bedside instruments are available for the routine ward and ICU setting. Several have been shown to have a high specificity and sensitivity when compared with the standard definitions according to DSM-IV-TR and ICD-10. The Confusion Assessment Method (CAM) and a version specifically developed for the intensive care setting (CAM-ICU) have emerged as a standard. However, alternatives allowing grading of the severity of delirium are also available. In many units, the approach to delirium follows a three-step strategy. Initially, non-pharmacological multicomponent strategies are used for primary prevention. As a second step, pharmacological prophylaxis may be added. Perioperative administration of haloperidol has been shown to reduce the severity, but not the incidence, of delirium. Perioperative administration of atypical antipsychotics has been shown to reduce the incidence of delirium in specific groups of patients. In patients with delirium, both symptomatic and causal treatment of delirium need to be considered. So far symptomatic treatment of delirium is primarily based on antipsychotics. Currently, cholinesterase inhibitors cannot be recommended and the data on dexmedetomidine are inconclusive. With the exception of alcohol-withdrawal delirium, there is no role for benzodiazepines in the treatment of delirium. It is unclear whether treating delirium prevents long-term sequelae.

Early detection of idiopathic Parkinson's disease based on magnetic resonance imaging

The diagnosis of idiopathic Parkinson's disease (IPD) is entirely clinical. The fact that neuronal damage begins 5-10 years before occurrence of sub-clinical signs, underlines the importance of preclinical diagnosis. A new approach for in-vivo pathophysiological assessment of IPD-related neurodegeneration was implemented based on recently developed neuroimaging methods. It is based on non- invasive magnetic resonance data sensitive to brain tissue property changes that precede macroscopic atrophy in the early stages of IPD. This research aims to determine the brain tissue property changes induced by neurodegeneration that can be linked to clinical phenotypes which will allow us to create a predictive model for early diagnosis in IPD. We hypothesized that the degree of disease progression in IPD patients will have a differential and specific impact on brain tissue properties used to create a predictive model of motor and non-motor impairment in IPD. We studied the potential of in-vivo quantitative imaging sensitive to neurodegeneration- related brain tissue characteristics to detect changes in patients with IPD. We carried out methodological work within the well established SPM8 framework to estimate the sensitivity of tissue probability maps for automated tissue classification for detection of early IPD. We performed whole-brain multi parameter mapping at high resolution followed by voxel-based morphometric (VBM) analysis and voxel-based quantification (VBQ) comparing healthy subjects to IPD patients. We found a trend demonstrating non-significant tissue property changes in the olfactory bulb area using the MT and R1 parameter with p<0.001. Comparing to the IPD patients, the healthy group presented a bilateral higher MT and R1 intensity in this specific functional region. These results did not correlate with age, severity or duration of disease. We failed to demonstrate any changes with the R2* parameter. We interpreted our findings as demyelination of the olfactory tract, which is clinically represented as anosmia. However, the lack of correlation with duration or severity complicates its implications in the creation of a predictive model of impairment in IPD.

Iowa African-American Journal, Fall 2005, Vol. 11, no. 1

Newsletter for the Iowa Commission on the Status of African-Americans

Fresh News; The Farmers' Market Newsletter, Fall 2004

Newsletter produced by Iowa Department of Agriculture and Land Stewardship

Fresh News; The Farmers' Market Newsletter, Fall 2005

Newsletter produced by Iowa Department of Agriculture and Land Stewardship

White Cane Update, Fall 2004

The White Cane Update newsletter includes information about the latest happenings at the Iowa Department for the Blind.

White Cane Update, Fall 2005

The White Cane Update newsletter includes information about the latest happenings at the Iowa Department for the Blind.

Independent Living Program, Fall 2006

A Day in the Life of Agnes.