MONTE CARLO SIMULATION OF ORANGE JUICE PECTINMETHYLESTERASE (PME) INACTIVATION BY COMBINED PROCESSES OF HIGH HYDROSTATIC PRESSURE (HHP) AND TEMPERATURE

The variability effect of kinetic data was investigated by simulating orange juice pectinmethylesterase (PME) inactivation with combined processes of high hydrostatic pressure-temperature (100-500 MPa; 20-40°C), applying the Monte Carlo method. Parameters from an Eyring-Arrheniius model that predicts the kinetic inactivation constant (k) as a function of both pressure and temperature were found reported in literature and considered for the analysis. The kinetic analysis was carried out with both Monte Carlo simulations and the traditional deterministic approach, which only considers mean values and does not take into account data variability. Simulations with the Monte Carlo method demonstrated that residual PME activity predicted with deterministic calculations greatly differed from those obtained through confidence intervals of simulated probabilistic distributions. Mean values overrated residual enzyme activity from 4% to ≈2,800% when compared to the 95% confidence intervals generated with the Monte Carlo method. This divergence augmented as both applied pressure and temperature levels increased. Similar risk analysis projects can be further developed to establish the foundations for future food processing regulations of enzymatic control.This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Universidad Autónoma Metropolitana Unidad Iztapalapa and can be found at: http://www.redalyc.org/revista.oa?id=620.Keywords: Process simulation, High hydrostatic pressure (HHP), Orange juice, Pectinmethylesterase (PME), Monte CarloKeywords: Process simulation, High hydrostatic pressure (HHP), Orange juice, Pectinmethylesterase (PME), Monte Carl

“INDUCCIÓN DEL DAÑO AL ADN IN VITRO POR CICLOFOSFAMIDA MEDIDO CON EL ENSAYO COMETA Y SU ASOCIACIÓN CON LOS POLIMORFISMOS DE GST”

Resumen: La GST es una familia de enzimas que codifica varios genes polimórficos GSTM1, GSTT1, GSTP1 que apoyan en el proceso de eliminación de la ciclofosfamida (CF), se utiliza en el tratamiento de neoplasias, es un profármaco que requiere ser activado por el CYP450 y biotransformado en mostaza fosforamida, agente alquilante bifuncional, que forma aductos y enlaces cruzados con el ADN. Se ha propuesto que los genes GSTTI, GSTMI, GSTPI influyen en la susceptibilidad a nivel individual en la respuesta al tratamiento. Existen una gran variedad de ensayos para evaluar daños al ADN entre ellos la microelectroforesis unicelular comúnmente llamada ensayo cometa, que en condiciones alcalinas, detecta rupturas y sitios sensibles al álcali generados por agentes genotóxicos. . El objetivo de este trabajo fue investigar que la magnitud del daño al ADN in vitro inducido por la ciclofosfamida en linfocitos de sangre periférica es modulada por los polimorfismos de GSTT1, GSTM1 y GSTP1. En este estudio transversal se procesaron 120 muestras de sangre periférica de individuos sanos de indistinto sexo. Se hizo la inducción del daño al ADN con cliclofosfamida y la genotipificación de los polimorfismos de GST. Los resultados mostraron heterogeneidad entre los individuos en relación al daño inducido por ciclofosfamida. Se identificaron 12 genotipos completos. Se encontró que el genotipo silvestre (TI + / M + / PIb a/a / PIc a/a) que posee mayor actividad metabolizadora es estadísticamente significativa al compararlo con los 11 genotipos restantes. La magnitud del daño al ADN se asocia a la presencia de los polimorfismos de GSTM1, GSTT1 y GSTP1 de manera conjunta. Este es uno de los primeros trabajos en la población mexicana donde se observa que los polimorfismos de GSTM1, GSTT1, GSTP1 influyen en la respuesta a ciclofosfamida en linfocitos de sangre periférica in vitro evaluado mediante el ensayo cometa

A Robot Supervision Architecture for Safe and Efficient Space Exploration and Operation

Current NASA plans envision human beings returning to the Moon in 2018 and, once there, establishing a permanent outpost from which we may initiate a long-term effort to visit other planetary bodies in the Solar System. This will be a bold, risky, and costly journey, comparable to the Great Navigations of the fifteenth and sixteenth centuries. Therefore, it is important that all possible actions be taken to maximize the astronauts ’ safety and productivity. This can be achieved by deploying fleets of autonomous robots for mineral prospecting and mining, habitat construction, fuel production, inspection and maintenance, etc.; and by providing the humans with the capability to telesupervise the robots ’ operation and to teleoperate them whenever necessary or appropriate, all from a safe, “shirtsleeve ” environment. This paper describes the authors ’ work in progress on the development of a Robot Supervision Architecture (RSA) for safe and efficient space exploration and operation. By combining the humans ’ advanced reasoning capabilities with the robots ’ suitability for harsh space environments, we will demonstrate significan

A Robot Supervision Architecture for Safe and Efficient Space Exploration and Operation

Current NASA plans envision human beings returning to the Moon in 2018 and, once there, establishing a permanent outpost from which we may initiate a long-term effort to visit other planetary bodies in the Solar System. This will be a bold, risky, and costly journey, comparable to the Great Navigations of the fifteenth and sixteenth centuries. Therefore, it is important that all possible actions be taken to maximize the astronauts’ safety and productivity. This can be achieved by deploying fleets of autonomous robots for mineral prospecting and mining, habitat construction, fuel production, inspection and maintenance, etc.; and by providing the humans with the capability to telesupervise the robots’ operation and to teleoperate them whenever necessary or appropriate, all from a safe, “shirtsleeve” environment. This paper describes the authors’ work in progress on the development of a Robot Supervision Architecture (RSA) for safe and efficient space exploration and operation. By combining the humans’ advanced reasoning capabilities with the robots’ suitability for harsh space environments, we will demonstrate significant productivity gains while reducing the amount of weight that must be lifted from Earth – and, therefore, cost. Our first instantiation of the RSA is a wide-area mineral prospecting task, where a fleet of robots survey a pre-determined area autonomously, sampling for minerals of interest. When the robots require assistance – e.g., when they encounter navigation problems, reach a prospecting site, or find a potentially interesting rock formation – they signal a human telesupervisor at base, who intervenes via a high-fidelity geometrically-correct stereoscopic telepresence system (Figure 1a). In addition to prospecting, the RSA applies to a variety of other tasks, both on the surface: mining, transporting, and construction – and on-orbit: construction, inspection, and repair of large space structures and satellites (Figure 1b). This paper is structured as follows: In the following section we present related work and emphasize the contribution we bring to the state-of-the-art. Next, we describe the robot supervision architecture, which is the overarching paradigm under which all other modules function. We then turn our attention to the main focus of the paper, our current system implementation and results, where three rovers at Carnegie Mellon University (CMU), NASA Ames Research Center (ARC) and NASA Jet Propulsion Laboratory (JPL) visit targets simulating regions of interest for prospecting, both in autonomous and teleoperated modes. The paper closes with conclusions and plans for future work