Mitochondrial DNA Damage and Animal Longevity: Insights from Comparative Studies

Chemical reactions in living cells are under strict enzyme control and conform to a tightly regulated metabolic program. However, uncontrolled and potentially deleterious endogenous reactions occur, even under physiological conditions. Aging, in this chemical context, could be viewed as an entropic process, the result of chemical side reactions that chronically and cumulatively degrade the function of biological systems. Mitochondria are a main source of reactive oxygen species (ROS) and chemical sidereactions in healthy aerobic tissues and are the only known extranuclear cellular organelles in animal cells that contain their own DNA (mtDNA). ROS can modify mtDNA directly at the sugar-phosphate backbone or at the bases, producing many different oxidatively modified purines and pyrimidines, as well as single and double strand breaks and DNA mutations. In this scenario, natural selection tends to decrease the mitochondrial ROS generation, the oxidative damage to mtDNA, and the mitochondrial mutation rate in long-lived species, in agreement with the mitochondrial oxidative stress theory of aging

Diseño e implementación de la supervisión, el control y la simulación de un proceso químico

Dentro del contexto de la Automatización Industrial se encuentran los sistemas de información y comunicación Industriales, los cuales permiten el desarrollo y la mejora de infinidad de procesos industriales. Con esto se consiguen mejoras en la producción y calidad, disminución de riesgos laborales, etc. A continuación se describe el diseño y la implementación de la supervisión, el control y la simulación de un proceso químico, en concreto el procesado de la leche cruda hasta la obtención de la leche pasteurizada, apta para su envasado y su consumo. Para ello se ha realizado un sistema SCADA (Supervisory Control and Data Adquisition) a partir del cual se puede realizar la supervisión y el control del proceso. Para ello se ha utilizado el software de Wonderware, InTouch 2014 R2; todo ello controlado a través del software para controladores de PLCs ( Programmable Logic Controller) de la marca RockWell, RSLogix 5000 todo ello simulando los valores con el emulador RSLogix Emulate de Allen Bradley. Esto permite trabajar con los PLC de la gama 5000 y simular su desarrollo. Gracias a todo esto ha sido posible llevar a cabo el diseño del proceso escogido, de forma correcta ajustándose en todo momento al proceso real para que éste sea desarrollado y controlado mediante dicha programación

Associação entre o tabagismo e a apresentação de carcinoma basocelular

Trabalho de Conclusão de Curso - Universidade Federal de Santa Catarina. Curso de Medicina. Departamento de Clinica Medica

Climate change e geopolitical accountability: a spacebusiness perspective at ghgsa

This work examines the relationship between private companies and geopolitical problems through a case study setting. The business case of GHGSat demonstrates how the new Space business frontier is helping society tackle accountability problems for climate change agreements. First it explains a brief history of space ventures and how the principal determinants of success have been changing towards a more market-friendly environment and fostering entrepreneurial solutions for social problems. It sets out the context of the climate change challenge and how the diplomatic and geopolitical path is struggling with accountability and monitoring of greenhouse gas emissions by countries and companies