Racional: Aproximadamente um de cada cinco pacientes hospitalizados por pneumonia adquirida na comunidade (PAC) apresenta uma resposta clínica inadequada, sendo a mortalidade nestes pacientes de 40%. Os objetivos do estudo foram: determinar a incidência e as variáveis de associação independente com fracasso terapêutico da PAC, e os fatores prognósticos da PAC tratada em ambiente hospitalar. Métodos: Estudo de coorte, prospectivo, multicêntrico, com 425 pacientes hospitalizados por PAC. Os pacientes foram acompanhados de forma sistemática para identificação do fracasso terapêutico e seguidos até a alta hospitalar. Resultados: A incidência de fracasso terapêutico foi de 14,6% (62/425). Os preditores independentes de risco para o fracasso foram: insuficiência renal aguda à admissão (OR 2,9; IC 95% 1,2-7,2; p=0,017), progressão radiológica (OR 29,8; IC 95 8,1-109,7%; p<0,001), derrame pleural (OR 3,4; IC 95% 1,3-8,6; p=0,010), relação PaO2/FiO2 inferior a 250 à admissão (OR 2,7; IC 95% 1,1-6,7; p=0,017) e PSI classe V (OR 2,7; IC 95% 1,1-7,0; p=0,042). A mortalidade geral foi de 7,5%, e de 40,3% nos pacientes com fracasso. O fracasso terapêutico foi o principal fator independente de mortalidade na PAC (OR 85,3, IC 95% 18,8-387,4, p<0,0001). Conclusão: O fracasso terapêutico da PAC é freqüente, está associado a marcadores clínicos, radiológicos e laboratoriais identificáveis desde a admissão hospitalar (ou nos primeiros dias de acompanhamento), sendo o principal preditor independente de mortalidade. / Rational: One out of five patients hospitalized for community-acquired pneumonia (CAP) might have an inadequate response to empirical antimicrobial treatment, and the mortality among these patients may reach rates of up to 40%. The aims of the study were to: quantify the incidence of empirical treatment failure in CAP, identify risk factors for therapeutic failure and prognostic factors in CAP. Methods: Prospective, multicenter cohort study of 425 hospitalized patients for CAP. The systematic identification of treatment failure required a daily follow-up until hospital discharge. Results: The incidence of treatment failure was 14.6% (62/425). The independent risk factors associated with therapeutic failure in a logistic analysis were: acute renal failure (OR 2.9; 95% CI 1.2-7.2; p=0.017), radiological progression (OR 29.8; IC 95 8.1-109.7%; p<0.001), pleural effusion (OR 3.4; 95% CI 1.3-8.6; p=0.010), PaO2/FiO2 ratio < 250 (OR 2.7; 95% CI 1.1-6.7; p=0.017) e pneumonia severity index Class V (OR 2.7; 95% CI 1.1-7.0; p=0.042). Mortality was significantly higher in patients with therapeutic failure (40.3% vs. 7.5%). Treatment failure was the main prognostic factor associated with CAP (OR 85.3; 95% CI 18.8-387.4, p<0.0001). Conclusion: The treatment failure is frequently found and it is associated with clinical, radiological and laboratorial markers. It is also an important independent predictor of mortality in CAP.

This study investigated the item parameter recovery of two methods of factor analysis. The methods researched were a traditional factor analysis of tetrachoric correlation coefficients and an IRT approach to factor analysis which utilizes marginal maximum likelihood estimation using an EM algorithm (MMLE-EM). Dichotomous item response data was generated under the 2-parameter normal ogive model (2PNOM) using PARDSIM software. Examinee abilities were sampled from both the standard normal and uniform distributions. True item discrimination, a, was normal with a mean of .75 and a standard deviation of .10. True b, item difficulty, was specified as uniform [-2, 2]. The two distributions of abilities were completely crossed with three test lengths (n= 30, 60, and 100) and three sample sizes (N = 50, 500, and 1000). Each of the 18 conditions was replicated 5 times, resulting in 90 datasets. PRELIS software was used to conduct a traditional factor analysis on the tetrachoric correlations. The IRT approach to factor analysis was conducted using BILOG 3 software. Parameter recovery was evaluated in terms of root mean square error, average signed bias, and Pearson correlations between estimated and true item parameters. ANOVAs were conducted to identify systematic differences in error indices. Based on many of the indices, it appears the IRT approach to factor analysis recovers item parameters better than the traditional approach studied. Future research should compare other methods of factor analysis to MMLE-EM under various non-normal distributions of abilities.

No description available.

Se investigó la relación entre el engagement y la percepción del colaborador sobre la relación con su jefe. La muestra estuvo compuesta por 162 colaboradores de empresas, de los cuales el 53.1% fueron hombres mientras que el 46.9% fueron mujeres con un promedio de 29.8 años de edad. Debían formar parte de un equipo de trabajo. Los participantes respondieron la encuesta de bienestar en el trabajo (UWES) y la encuesta de percepción de intercambio líder – miembro (LMX-MDM). Se hipotetizó una relación directa, positiva y significativa entre las variables percepción del líder y engagement. De acuerdo a lo hipotetizado, los resultados mostraron que la variable percepción en el intercambio líder-miembro, compuesta por los factores respeto hacia el supervisor y trabajo positivo con el supervisor, se relaciona positivamente con el engagement, compuesta por los factores actitud positiva en el trabajo y continuidad en el trabajo. Esta investigación podrá ser utilizada como base para investigaciones futuras acerca de las dinámicas grupales en equipos de trabajo corporativos. / The relationship between engagement and the employee’s perception of the relationship with their boss was investigated. The sample was composed of 162 employees of which 53.1% were men while 46.9% were women with an average of 29.8 years of age. Necessarily, they should be part of a work team. Participants responded to the survey on well-being at work (UWES) and the leader-member exchange perception survey (LMX-MDM). A direct, positive and significant relationship between the variables was hypothesized. The results showed that the variable engagement, composed of positive attitude and continuity at work is positively related to the variable perception of the leader-member exchange, composed of respect towards the supervisor and positive work with supervisor. Through this investigation, business leaders will be able to modify their behavior around employees, strengthening their relationship. They may implement strategies to improve work engagement through actions directed towards the collaborator’s well-being. Also, this research may be used as a basis for future research about group dynamics in corporate work teams. / Tesis

No description available.

Yes / This research critically analyzes the Interpretive Ranking Process (IRP) using an illustrative empirically derived IS project failure related case study to articulate a deeper understanding of the method. The findings emphasize the suitability of the method for a number of practical applications, but also highlight the limitations for larger matrix sized problems. The IRP process to derive the dominance between IS project failure factors is judged to be methodical and systematic, enabling the development of clear dominating interactions.

No / 1 In this study we examined the signalling events that regulate lipopolysaccharide (LPS)-stimulated induction of interferon regulatory factor (IRF)-1 in human umbilical vein endothelial cells (HUVECS). 2 LPS stimulated a time- and concentration-dependent increase in IRF-1 protein expression, an effect that was mimicked by the cytokine, tumour necrosis factor (TNF)-¿. 3 LPS stimulated a rapid increase in nuclear factor kappa B (NFKB) DNA-binding activity. Preincubation with the NFKB pathway inhibitors, N-¿-tosyl-L-lysine chloromethyl ketone (TLCK) or pyrrolidine dithiocarbamate (PDTC), or infection with adenovirus encoding IKB¿, blocked both IRF-1 induction and NFKB DNA-binding activity. 4 LPS and TNF¿ also stimulated a rapid activation of gamma interferon activation site/gamma interferon activation factor (GAS/GAF) DNA-binding in HUVECs. Preincubation with the Janus kinase (JAK)-2 inhibitor, AG490 blocked LPS-stimulated IRF-I induction but did not affect GAS/ GAF DNA-binding. 5 Preincubation with TLCK, PDTC or infection with I¿Ba adenovirus abolished LPS-stimulated GAS/GAF DNA-binding. 6 Incubation of nuclear extracts with antibodies to RelA/p50 supershifted GAS/GAF DNA-binding demonstrating the involvement of NF¿B isoforms in the formation of the GAS/GAF complex. 7 These studies show that NF¿B plays an important role in the regulation of IRF-1 induction in HUVECs. This is in part due to the interaction of NF¿B isoforms with the GAS/GAF complex either directly or via an intermediate protein.

In this study, an improved correlational procedure for factor-analyzing dichotomously-scored item response data is described and tested. The procedure involves (a) replacing the dichotomous input values with continuous probability values obtained through Rasch analysis; (b) calculating interitem product-moment correlations among the probabilities; and (c) subjecting the correlations to unweighted least-squares factor analysis. Two simulated data sets and an empirical data set (Kentucky Comprehensive Listening Test responses) were used to compare the new procedure with two more traditional techniques, using (a) phi and (b) tetrachoric correlations calculated directly from the dichotomous item-response values. The three methods were compared on three criterion measures: (a) maximum internal correlation; (b) product of the two largest factor loadings; and (c) proportion of variance accounted for. The Rasch-based procedure is recommended for subjecting dichotomous item response data to latent-variable analysis.

MEMS gyroscopes are electromechanical devices that measure rate or angle of rotation. They are one of the fastest growing segments of the microsensor market. Advances in microfabrication technologies have enabled the implementation of chip scale monolithic gyroscopes (MEMS gyroscopes) with very small form factor that are lightweight and consume little power. Over the past decade, significant amount of research have been directed towards the development of high performance and very small size MEMS gyroscopes for applications in consumer electronics such as smart phones. In this dissertation, high aspect-ratio hemispherical shell structure with continuously curved surface is utilized as the high Q resonator. Being an axial symmetric structure, the 3D hemispherical shell is able to achieve low frequency (3 ~ 5 kHz) within 2 mm X 2mm die area. Detailed analysis on energy dissipation also shows its potential to achieve ultra-high quality factor with the selection of high Q material and proper design of support structure. This dissertation presents, for the first time, the analysis, design, fabrication and characterization of a micro-hemispherical resonating gyroscope (μHRG) that has the potential to be used as a whole angle micro-gyroscope. A three-dimensional high aspect-ratio poly- and single crystalline silicon (3D HARPSS) process is developed to fabricate free-standing, stem-supported hemispherical shell with self-aligned deep electrodes for driving, sensing and quadrature control of the gyroscope. This monolithic process consists of seven lithography steps and combines 3D micro-structure with curved surfaces with the HARPSS process to create capacitive electrodes with arbitrary gaps around the micro-hemispherical shell resonator (μHSR). Polysilicon is utilized as the structural material due to its isotropic mechanical properties and the potential of achieving high quality factor. The fabrication is demonstrated successfully by prototypes of polysilicon μHRG with diameter of 1.2 mm and thickness of 700 nm. Frequency response and gyro operation are electronically measured using the integrated electrodes. Quality factor of 8,500 is measured with frequency mismatch of 105 Hz. Electronic mode matching and alignment are successfully performed by applying tuning voltages and quadrature nulling voltages. An open loop rate sensitivity scale factor of 4.42 mV/°/s was measured. Design and process optimization of the support structure improved the quality factor to 40,000. Further improvement of quality factor will enable the demonstration of high performance RIG using polysilicon μHRG.

published_or_final_version / abstract / Surgery / Doctoral / Doctor of Philosophy