Impact of age, various forms of cataract, and visual acuity on whole-field scotopic sensitivity screening for glaucoma in rural Taiwan.

OBJECTIVE: To evaluate the impact of age, various forms of cataract, and visual acuity on whole-field scotopic sensitivity screening for glaucoma in a rural population. DESIGN: Clinic-based study with population-based recruitment. SETTING: Jin Shan Township near Taipei, Taiwan. SUBJECTS: Three hundred forty-six residents (ages, > or = 40 years) of Jin Shan Township. INTERVENTIONS: Whole-field scotopic testing, ophthalmoscopy with dilation of the pupils, cataract grading against photographic standards, and screening visual field testing in a random one-third subsample. MAIN OUTCOME MEASURES: Whole-field scotopic sensitivity (in decibels) and diagnostic status as a case of glaucoma, glaucoma suspect, or normal. RESULTS: Participants in Jin Shan Township did not differ significantly in the rate of blindness, low visual acuity, or family history of glaucoma from a random sample of nonrespondents. Scotopic sensitivity testing detected 100% (6/6) of subjects with open-angle glaucoma at a specificity of 80.2%. The mean +/- SE scotopic sensitivity for six subjects with open-angle glaucoma (32.78 +/- 1.51 dB) differed significantly from that of 315 normal individuals (38.51 +/- 0.22 dB), when adjusted for age and visual acuity (P = .05, t test). With linear regression modeling, factors that correlated significantly with scotopic sensitivity were intraocular pressure, screening visual field, best corrected visual acuity, presence of cortical cataract, and increasing age. CONCLUSIONS: Although cataract affects the whole-field scotopic threshold, it appears that scotopic testing may be of value in field-based screening for glaucoma.

Analyse par apprentissage automatique des réponses fMRI du cortex auditif à des modulations spectro-temporelles

L'application de classifieurs linéaires à l'analyse des données d'imagerie cérébrale (fMRI) a mené à plusieurs percées intéressantes au cours des dernières années. Ces classifieurs combinent linéairement les réponses des voxels pour détecter et catégoriser différents états du cerveau. Ils sont plus agnostics que les méthodes d'analyses conventionnelles qui traitent systématiquement les patterns faibles et distribués comme du bruit. Dans le présent projet, nous utilisons ces classifieurs pour valider une hypothèse portant sur l'encodage des sons dans le cerveau humain. Plus précisément, nous cherchons à localiser des neurones, dans le cortex auditif primaire, qui détecteraient les modulations spectrales et temporelles présentes dans les sons. Nous utilisons les enregistrements fMRI de sujets soumis à 49 modulations spectro-temporelles différentes. L'analyse fMRI au moyen de classifieurs linéaires n'est pas standard, jusqu'à maintenant, dans ce domaine. De plus, à long terme, nous avons aussi pour objectif le développement de nouveaux algorithmes d'apprentissage automatique spécialisés pour les données fMRI. Pour ces raisons, une bonne partie des expériences vise surtout à étudier le comportement des classifieurs. Nous nous intéressons principalement à 3 classifieurs linéaires standards, soient l'algorithme machine à vecteurs de support (linéaire), l'algorithme régression logistique (régularisée) et le modèle bayésien gaussien naïf (variances partagées).

Aggression and accountability : how caregivers and law enforcers cope

Objectif. L’objectif est de comprendre comment les intervenants en relation d’aide et les agents des forces de l’ordre composent avec la violence au travail et le stress lié à l’imputabilité. Un cadre théorique basé sur l’identité professionnelle est proposé afin de comprendre la modulation de la santé psychologique au travail et testé via le Professional Quality of Life des intervenants en protection de la jeunesse. Les facteurs de prédiction de la banalisation de la violence au travail et des impacts psychologiques de cette banalisation sont également étudiés. Méthodologie. Un sondage mené auprès d’un échantillon représentatif constitué de 301 intervenants en protection de la jeunesse a permis d’examiner le Professional Quality of Life. Les effets de l’exposition à la violence en milieu de travail, à l’exposition au matériel traumatique et du stress lié à l’imputabilité sur la fatigue de compassion ont été analysés à l’aide d’équation structurelle. Les effets indirects attribuables au genre, au soutien organisationnel perçu, à l’adhésion à l’identité professionnelle, aux stratégies d’adaptation et à la confiance en ses moyens pour gérer un client agressif ont été mesurés. Pour l’examen des facteurs de prédiction de la banalisation de la violence au travail, les résultats d’un sondage mené auprès de 1141 intervenants en relation d’aide et des forces de l’ordre ont été analysés à l’aide de régression linéaire. L’analyse des réponses des 376 intervenants de cet échantillon ayant rapporté avoir été perturbé par un acte de violence au travail a permis de mesurer l’impact de la banalisation sur les conséquences psychologiques suite à une victimisation au travail. Les effets indirects attribuables à la banalisation de la violence ont été mesurés. Des analyses différenciées en fonction du sexe ont également été menées. Résultats. L’exposition à la violence, le sentiment d’imputabilité et l’évitement amplifiaient la fatigue de compassion chez les intervenants en protection de la jeunesse sondés. Les attitudes masculines, l’adhésion à l’identité professionnelle, la confiance en ses moyens pour gérer les clients agressifs l’atténuaient. Quant aux facteurs de prédiction de la banalisation de la violence au travail, les participants masculins étaient plus enclins que les femmes à la normaliser. Les agents des forces de l’ordre percevaient davantage la violence comme tabou que les intervenants en relation d’aide. Les facteurs organisationnels avaient tous un effet négatif sur le tabou entourant la violence au travail. Finalement, l’âge, les victimisations antérieures, les blessures graves et percevoir la violence au travail comme un tabou augmentaient le nombre de conséquences psychologiques suite à une victimisation. Les analyses différenciées en fonction du sexe ont identifié des facteurs de prédiction spécifiques aux hommes et aux femmes. Implications. Lors de déploiement de stratégies organisationnelles afin d’aider les employés à gérer avec les stress liés au travail, les organisations doivent considérer l’identité professionnelle de leur travailleur ainsi que des différences en fonction du sexe et du genre.

Sources of variation in the ampicillin-resistant Escherichia coli concentration in the feces of organic broiler chickens

Currently, there are limited published data for the population dynamics of antimicrobial-resistant commensal bacteria. This study was designed to evaluate both the proportions of the Escherichia coli populations that are resistant to ampicillin at the level of the individual chicken on commercial broiler farms and the feasibility of obtaining repeated measures of fecal E. coli concentrations. Short-term temporal variation in the concentration of fecal E. coli was investigated, and a preliminary assessment was made of potential factors involved in the shedding of high numbers of ampicillin-resistant E. coli by growing birds in the absence of the use of antimicrobial drugs. Multilevel linear regression modeling revealed that the largest component of random variation in log-transformed fecal E. coli concentrations was seen between sampling occasions for individual birds. The incorporation of fixed effects into the model demonstrated that the older, heavier birds in the study were significantly more likely (P = 0.0003) to shed higher numbers of ampicillin-resistant E. coli. This association between increasing weight and high shedding was not seen for the total fecal E. coli population (P = 0.71). This implies that, in the absence of the administration of antimicrobial drugs, the proportion of fecal E. coli that was resistant to ampicillin increased as the birds grew. This study has shown that it is possible to collect quantitative microbiological data on broiler farms and that such data could make valuable contributions to risk assessments concerning the transfer of resistant bacteria between animal and human populations.

On the observability of turbulent transport rates by Argo: supporting evidence from an inversion experiment

Although estimation of turbulent transport parameters using inverse methods is not new, there is little evaluation of the method in the literature. Here, it is shown that extended observation of the broad scale hydrography by Argo provides a path to improved estimates of regional turbulent transport rates. Results from a 20 year ocean state estimate produced with the ECCO v4 non-linear inverse modeling framework provide supporting evidence. Turbulent transport parameter maps are estimated under the constraints of fitting the extensive collection of Argo profiles collected through 2011. The adjusted parameters dramatically reduce misfits to in situ profiles as compared with earlier ECCO solutions. They also yield a clear reduction in the model drift away from observations over multi-century long simulations, both for assimilated variables (temperature and salinity) and independent variables (bio-geochemical tracers). Despite the minimal constraints imposed specifically on the estimated parameters, their geography is physically plausible and exhibits close connections with the upper ocean ocean stratification as observed by Argo. The estimated parameter adjustments furthermore have first order impacts on upper-ocean stratification and mixed layer depths over 20 years. These results identify the constraint of fitting Argo profiles as an effective observational basis for regional turbulent transport rates. Uncertainties and further improvements of the method are discussed.

A generalized data windowing scheme for adaptive conjugate gradient algorithms

The performance of the modified adaptive conjugate gradient (CG) algorithms based on the iterative CG method for adaptive filtering is highly related to the ways of estimating the correlation matrix and the cross-correlation vector. The existing approaches of implementing the CG algorithms using the data windows of exponential form or sliding form result in either loss of convergence or increase in misadjustment. This paper presents and analyzes a new approach to the implementation of the CG algorithms for adaptive filtering by using a generalized data windowing scheme. For the new modified CG algorithms, we show that the convergence speed is accelerated, the misadjustment and tracking capability comparable to those of the recursive least squares (RLS) algorithm are achieved. Computer simulations demonstrated in the framework of linear system modeling problem show the improvements of the new modifications.

Máquina de vetores-suporte intervalar

The Support Vector Machines (SVM) has attracted increasing attention in machine learning area, particularly on classification and patterns recognition. However, in some cases it is not easy to determinate accurately the class which given pattern belongs. This thesis involves the construction of a intervalar pattern classifier using SVM in association with intervalar theory, in order to model the separation of a pattern set between distinct classes with precision, aiming to obtain an optimized separation capable to treat imprecisions contained in the initial data and generated during the computational processing. The SVM is a linear machine. In order to allow it to solve real-world problems (usually nonlinear problems), it is necessary to treat the pattern set, know as input set, transforming from nonlinear nature to linear problem. The kernel machines are responsible to do this mapping. To create the intervalar extension of SVM, both for linear and nonlinear problems, it was necessary define intervalar kernel and the Mercer s theorem (which caracterize a kernel function) to intervalar function

Aplicação de sistemas multi-classificadores no diagnóstico de falhas em motores de indução trifásicos

Equipment maintenance is the major cost factor in industrial plants, it is very important the development of fault predict techniques. Three-phase induction motors are key electrical equipments used in industrial applications mainly because presents low cost and large robustness, however, it isn t protected from other fault types such as shorted winding and broken bars. Several acquisition ways, processing and signal analysis are applied to improve its diagnosis. More efficient techniques use current sensors and its signature analysis. In this dissertation, starting of these sensors, it is to make signal analysis through Park s vector that provides a good visualization capability. Faults data acquisition is an arduous task; in this way, it is developed a methodology for data base construction. Park s transformer is applied into stationary reference for machine modeling of the machine s differential equations solution. Faults detection needs a detailed analysis of variables and its influences that becomes the diagnosis more complex. The tasks of pattern recognition allow that systems are automatically generated, based in patterns and data concepts, in the majority cases undetectable for specialists, helping decision tasks. Classifiers algorithms with diverse learning paradigms: k-Neighborhood, Neural Networks, Decision Trees and Naïves Bayes are used to patterns recognition of machines faults. Multi-classifier systems are used to improve classification errors. It inspected the algorithms homogeneous: Bagging and Boosting and heterogeneous: Vote, Stacking and Stacking C. Results present the effectiveness of constructed model to faults modeling, such as the possibility of using multi-classifiers algorithm on faults classification

Modelagem de máquina pneumática recolhedora de frutos de café em terreiro usando análise por elementos finitos

Teve-se o objetivo de desenvolver um modelo matemático por meio de análise de elementos finitos, utilizando o programa computacional ANSYS®, versão 5.7, para otimizar o projeto de máquina recolhedora de frutos de café no terreiro. A modelagem da máquina foi realizada com base no levantamento das características aerodinâmicas dos frutos de café e da vazão de ar necessária para o transporte pneumático dos frutos. Foram obtidas, experimentalmente, as pressões estáticas nos dutos da máquina, sendo esses valores comparados com os resultados determinados pelo programa ANSYS, no intuito de validar o modelo. Com base nos resultados numéricos obtidos, concluiu-se que a modelagem desenvolvida apresentou resultados próximos aos determinados experimentalmente, obtendo erro relativo médio nos valores simulados de pressão de 9,2%. Por meio da modelagem, identificaram-se faixas de pressão que dificultariam o transporte pneumático dos frutos de café em alguns pontos da máquina. Esses problemas foram corrigidos e, com isso, o fluxo de ar proporcionado pelo ventilador foi suficiente para succionar os frutos de café no terreiro e transportá-los para dentro do reservatório da máquina. A modelagem desenvolvida atendeu às necessidades propostas no trabalho para o recolhimento dos frutos de café utilizando transporte pneumático eficientemente.

Construção,modelagem e controle de um pêndulo invertido com CLP e software scada

Pós-graduação em Engenharia Elétrica - FEIS

An investigation of computer literacy and attitudes amongst Greek post-graduate dental students

An accurate assessment of the computer skills of students is a pre-requisite for the success of any e-learning interventions. The aim of the present study was to assess objectively the computer literacy and attitudes in a group of Greek post-graduate students, using a task-oriented questionnaire developed and validated in the University of Malmö, Sweden. 50 post-graduate students in the Athens University School of Dentistry in April 2005 took part in the study. A total competence score of 0-49 was calculated. Socio-demographic characteristics were recorded. Attitudes towards computer use were assessed. Descriptive statistics and linear regression modeling were employed for data analysis. Total competence score was normally distributed (Shapiro-Wilk test: W = 0.99, V = 0.40, P = 0.97) and ranged from 5 to 42.5, with a mean of 22.6 (+/-8.4). Multivariate analysis revealed 'gender', 'e-mail ownership' and 'enrollment in non-clinical programs' as significant predictors of computer literacy. Conclusively, computer literacy of Greek post-graduate dental students was increased amongst males, students in non-clinical programs and those with more positive attitudes towards the implementation of computer assisted learning.

DEVELOPMENT OF A PREDICTIVE COMBUSTION MODEL OF A SPARK IGNITED ENGINE WITH GASOLINE DIRECT INJECTION, VARIABLE VALVE TIMING, DURATION AND LIFT TECHNOLOGIES

There is a need by engine manufactures for computationally efficient and accurate predictive combustion modeling tools for integration in engine simulation software for the assessment of combustion system hardware designs and early development of engine calibrations. This thesis discusses the process for the development and validation of a combustion modeling tool for Gasoline Direct Injected Spark Ignited Engine with variable valve timing, lift and duration valvetrain hardware from experimental data. Data was correlated and regressed from accepted methods for calculating the turbulent flow and flame propagation characteristics for an internal combustion engine. A non-linear regression modeling method was utilized to develop a combustion model to determine the fuel mass burn rate at multiple points during the combustion process. The computational fluid dynamic software Converge ©, was used to simulate and correlate the 3-D combustion system, port and piston geometry to the turbulent flow development within the cylinder to properly predict the experimental data turbulent flow parameters through the intake, compression and expansion processes. The engine simulation software GT-Power © is then used to determine the 1-D flow characteristics of the engine hardware being tested to correlate the regressed combustion modeling tool to experimental data to determine accuracy. The results of the combustion modeling tool show accurate trends capturing the combustion sensitivities to turbulent flow, thermodynamic and internal residual effects with changes in intake and exhaust valve timing, lift and duration.

The reporting quality of randomized controlled trials in orthodontics.

OBJECTIVES Accurate trial reporting facilitates evaluation and better use of study results. The objective of this article is to investigate the quality of reporting of randomized controlled trials (RCTs) in leading orthodontic journals, and to explore potential predictors of improved reporting. METHODS The 50 most recent issues of 4 leading orthodontic journals until November 2013 were electronically searched. Reporting quality assessment was conducted using the modified CONSORT statement checklist. The relationship between potential predictors and the modified CONSORT score was assessed using linear regression modeling. RESULTS 128 RCTs were identified with a mean modified CONSORT score of 68.97% (SD = 11.09). The Journal of Orthodontics (JO) ranked first in terms of completeness of reporting (modified CONSORT score 76.21%, SD = 10.1), followed by American Journal of Orthodontics and Dentofacial Orthopedics (AJODO) (73.05%, SD = 10.1). Journal of publication (AJODO: β = 10.08, 95% CI: 5.78, 14.38; JO: β = 16.82, 95% CI: 11.70, 21.94; EJO: β = 7.21, 95% CI: 2.69, 11.72 compared to Angle), year of publication (β = 0.98, 95% CI: 0.28, 1.67 for each additional year), region of authorship (Europe: β = 5.19, 95% CI: 1.30, 9.09 compared to Asia/other), statistical significance (significant: β = 3.10, 95% CI: 0.11, 6.10 compared to non-significant) and methodologist involvement (involvement: β = 5.60, 95% CI: 1.66, 9.54 compared to non-involvement) were all significant predictors of improved modified CONSORT scores in the multivariable model. Additionally, median overall Jadad score was 2 (IQR = 2) across journals, with JO (median = 3, IQR = 1) and AJODO (median = 3, IQR = 2) presenting the highest score values. CONCLUSION The reporting quality of RCTs published in leading orthodontic journals is considered suboptimal in various CONSORT areas. This may have a bearing in trial result interpretation and use in clinical decision making and evidence- based orthodontic treatment interventions.

Assessing the reporting quality in abstracts of randomized controlled trials in leading journals of oral implantology.

AIM Abstracts of randomized clinical trials are extremely important as trial appraisal is often based on the information included here. The objective of this study was to assess the quality of the reporting of RCT abstracts in journals of Oral Implantology. MATERIAL AND METHODS Six leading Implantology journals were screened for RCTs between years 2008 and 2012. A 21-item modified CONSORT for abstracts checklist was used to examine the completeness of abstract reporting. Descriptive statistics and linear regression modeling were employed for data analysis. RESULTS One hundred and sixty three RCT abstracts were included in this study. The majority of the RCTs were published in the Clinical Oral Implants Research (42.9%). The mean overall reporting quality score was 58.6% (95% CI: 57.6-59.7). The highest score was noted in the European Journal of Oral Implantology (63.8%; 95% CI: 61.8-65.8). Multivariate analysis demonstrated that abstract quality score was related to publication journal and number of research centers involved. Most abstracts adequately reported interventions (89.0%), objectives (77.9%) and conclusions (74.8%) while failed to report randomization procedures, allocation concealment, effect estimate, confidence intervals, and funding. Registration of RCTs was not reported in any of the abstracts. CONCLUSIONS The reporting quality in abstracts of RCTs published in Oral Implantology journals needs to be improved. Editors and authors should be encouraged to endorse the CONSORT for abstracts guidelines in order to achieve optimal quality in abstract reporting.

Dietary intake patterns and relationships to polybrominated diphenyl ether (PBDE) and phthalate body burden

Polybrominated diphenyl ethers (PBDEs) and phthalates are chemicals of concern because of high levels measured in people and the environment as well as the demonstrated toxicity in animal studies and limited epidemiological studies. Exposure to these chemicals has been associated with a range of toxicological outcomes, including developmental effects, behavioral changes, endocrine disruption, effects on sexual health, and cancer. Previous research has shown that both of these classes of chemicals contaminate food in the United States and worldwide. However, how large a role diet plays in exposure to these chemicals is currently unknown. To address this question, an exploratory analysis of data collected as part of the 2003-04 National Health and Nutrition Examination Survey (NHANES) was conducted. Associations between dietary intake (assessed by 24-hour dietary recalls) for a range of food types (meat, poultry, fish, and dairy) and levels PBDEs and phthalate metabolites were analyzed using multiple linear regression modeling. Levels of individual PBDE congeners 28, 47, 99, 100 as well as total PBDEs were found to be significantly associated with the consumption of poultry. Metabolites of di-(2-ethylhexyl) phthalate (DEHP) were found to be associated with the consumption of poultry, as well as with an increased consumption of fat of animal origin. These results, combined with results from previous studies, suggest that diet is an important route of intake for both PBDEs and phthalates. Further research needs to be conducted to determine the sources of food contamination with these toxic chemicals as well as to describe the levels of contamination of US food in a large, representative sample.^