Factors Associated with Revision Surgery after Internal Fixation of Hip Fractures

Background: Femoral neck fractures are associated with high rates of revision surgery after management with internal fixation. Using data from the Fixation using Alternative Implants for the Treatment of Hip fractures (FAITH) trial evaluating methods of internal fixation in patients with femoral neck fractures, we investigated associations between baseline and surgical factors and the need for revision surgery to promote healing, relieve pain, treat infection or improve function over 24 months postsurgery. Additionally, we investigated factors associated with (1) hardware removal and (2) implant exchange from cancellous screws (CS) or sliding hip screw (SHS) to total hip arthroplasty, hemiarthroplasty, or another internal fixation device. Methods: We identified 15 potential factors a priori that may be associated with revision surgery, 7 with hardware removal, and 14 with implant exchange. We used multivariable Cox proportional hazards analyses in our investigation. Results: Factors associated with increased risk of revision surgery included: female sex, [hazard ratio (HR) 1.79, 95% confidence interval (CI) 1.25-2.50; P = 0.001], higher body mass index (fo

The structure for unifying multiple modeling alternatives (SUMMA), Version 1.0: Technical Description

Este projeto de diplomação tem por objetivo apresentar todos os passos inerentes ao projeto de capacitores eletrolíticos de alumínio utilizados em aplicações industriais. Será discutida a base teórica do funcionamento de um capacitor eletrolítico junto a uma descrição do processo de fabricação desse tipo de capacitor. Adicionalmente, serão mostradas as características e comportamento de suas principais matérias primas na construção desse tipo de componente. Serão apresentados também o modelo térmico do capacitor e como é calculada sua estimativa de vida. Finalmente, serão apresentados os principais requisitos necessários para que se possa desenvolver um capacitor eletrolítico de alumínio junto a uma análise de suas principais características elétricas para determinar a melhor escolha para uma determinada aplicação.This work aims to demonstrate all the inherent steps for designing aluminum electrolytic capacitors used in industrial applications. The theoretical basis of how a electrolytic capacitor works will be discussed, together with the description of the manufacturing process for this type of capacitor. In addition, will be shown the characteristics and behavior of its main raw materials in the construction of this type of component. The thermal capacitor model and how its life estimate will be calculated will also be presented. Finally, will be presented the most important requirements for development of an aluminum electrolytic capacitor and electrical characteristics that must be considered to determine the best option for a specific application