MitoTrack, a user-friendly semi-automatic software for lineage tracking in living embryos

International audienceMotivation: During development, progenitor cells undergo multiple rounds of cellular divisions during which tran-scriptional programs must be faithfully propagated. Investigating the timing of transcriptional activation, which is a highly stochastic phenomenon, requires the analysis of large amounts of data. In order to perform automatic image analysis of transcriptional activation, we developed a software that segments and tracks both small and large objects, leading the user from raw data up to the results in their final form. Results: MitoTrack is a user-friendly open-access integrated software that performs the specific dual task of reporting the precise timing of transcriptional activation while keeping lineage tree history for each nucleus of a living developing embryo. The software works automatically but provides the possibility to easily supervise, correct and validate each step. Availability and implementation: MitoTrack is an open source Python software, embedded within a graphical user interface (download here)

Robustness against parametric noise of non ideal holonomic gates

Holonomic gates for quantum computation are commonly considered to be robust against certain kinds of parametric noise, the very motivation of this robustness being the geometric character of the transformation achieved in the adiabatic limit. On the other hand, the effects of decoherence are expected to become more and more relevant when the adiabatic limit is approached. Starting from the system described by Florio et al. [Phys. Rev. A 73, 022327 (2006)], here we discuss the behavior of non ideal holonomic gates at finite operational time, i.e., far before the adiabatic limit is reached. We have considered several models of parametric noise and studied the robustness of finite time gates. The obtained results suggest that the finite time gates present some effects of cancellation of the perturbations introduced by the noise which mimic the geometrical cancellation effect of standard holonomic gates. Nevertheless, a careful analysis of the results leads to the conclusion that these effects are related to a dynamical instead of geometrical feature.Comment: 8 pages, 8 figures, several changes made, accepted for publication on Phys. Rev.

Robustness of optimal working points for non-adiabatic holonomic quantum computation

Geometric phases are an interesting resource for quantum computation, also in view of their robustness against decoherence effects. We study here the effects of the environment on a class of one-qubit holonomic gates that have been recently shown to be characterized by "optimal" working times. We numerically analyze the behavior of these optimal points and focus on their robustness against noise.Comment: 14 pages, 8 figure

Enfoque para o manejo de resíduos não perigosos aproveitáveis, empregando uma estação ecológica

Introduction: This article is the result of the research project “Ecological Station based on renewable energies” currently developed by the Research Group on Technology and environment (gita) of the Corporación Universitaria Autónoma del Cauca and funded by the Human Talent Education Network Project for Social and Productive Innovation in the department of Cauca (InnovAcción Cauca), for a period of one year (September 2015 to 2016, the same month). Methodology: A review of the literature regarding the management of usable non-hazardous waste RnPA) is made, and includes technological trends and Management strategies. Additionally, a comparison is made based on the objectives of environmental education and major gaps and voids present when handling RnPA. Results: the architecture of an eco-friendly station (eco-station) as a pedagogical strategy, which integrates different forms of learning into the management RnPA during the collection stage.  Conclusions: material detection systems, user interaction, selection of waste and renewable energy supply within the eco-station streamline the learning process in the management and collection of RnPA at the source.Introducción: este artículo es producto del proyecto de investigación “Estación ecológica con base en energías renovables”, desarrollado actualmente por el Grupo de Investigación en Tecnología y Ambiente (GITA) de la Corporación Universitaria Autónoma del Cauca y financiado por el Proyecto Red de Formación de Talento Humano para la Innovación Social y Productiva en el departamento del Cauca (InnovAcción Cauca), por un periodo de un año (de septiembre del 2015 al 2016, del mismo mes). Metodología: se realiza una revisión de la literatura en relación con el manejo de residuos no peligrosos aprovechables (RnPA), presentando las tendencias tecnológicas y estrategias de manejo. Adicionalmente, se realiza una comparativa con base en los objetivos de la educación ambiental y se presentan las principales brechas y vacíos en el proceso de manejo de los RnPA. Resultados: la arquitectura de una estación ecológica-amigable (eco-estación) como estrategia pedagógica, donde se integran distintas formas de aprendizaje en el manejo de RnPA para su etapa de recolección. Conclusiones: los sistemas de detección de materiales, de interacción de usuario, de selección de residuos y de alimentación energética renovable en el interior de la eco-estación dinamizan el proceso de aprendizaje en el manejo y recolección en la fuente de RnPA.Introdução: este artigo é o resultado do projeto de investigação “Estação ecológica com base em energias renováveis”, desenvolvido atualmente pelo Grupo de Investigação em Tecnologia e Ambiente (gita) da Corporação Universitária Autónoma do Cauca e financiado pelo Projeto Rede de Formação de Talento Humano para a Inovação Social e Produtiva no departamento do Cauca (Inovação Cauca), por um período de um ano (de setembro de 2015 a 2016, do mesmo mês). Metodologia: é feita uma revisão da literatura no que tange o manejo de resíduos não perigosos aproveitáveis (RnPA), apresentando as tendências tecnológicas e estratégias de manejo. Adicionalmente, realiza-se uma comparação baseada nos objetivos da educação ambiental e apresentam-se os principais gaps e vazios no processo de manejo dos RnPA. Resultados: a arquitetura de uma estação ecológica-amigável (eco-estação) como estratégia pedagógica, onde se integram diversas formas de aprendizagem no manejo de RnPA para sua fase de coleta. Conclusões: os sistemas de detecção de materiais, de interação de usuário, de seleção de resíduos e de alimentação energética renovável no interior da eco-estação dinamizam o processo de aprendizado no manejo e coleta na fonte de RnPA

Using enhanced number and brightness to measure protein oligomerization dynamics in live cells

Protein dimerization and oligomerization are essential to most cellular functions, yet measurement of the size of these oligomers in live cells, especially when their size changes over time and space, remains a challenge. A commonly used approach for studying protein aggregates in cells is number and brightness (N&B), a fluorescence microscopy method that is capable of measuring the apparent average number of molecules and their oligomerization (brightness) in each pixel from a series of fluorescence microscopy images. We have recently expanded this approach in order to allow resampling of the raw data to resolve the statistical weighting of coexisting species within each pixel. This feature makes enhanced N&B (eN&B) optimal for capturing the temporal aspects of protein oligomerization when a distribution of oligomers shifts toward a larger central size over time. In this protocol, we demonstrate the application of eN&B by quantifying receptor clustering dynamics using electron-multiplying charge-coupled device (EMCCD)-based total internal reflection microscopy (TIRF) imaging. TIRF provides a superior signal-to-noise ratio, but we also provide guidelines for implementing eN&B in confocal microscopes. For each time point, eN&B requires the acquisition of 200 frames, and it takes a few seconds up to 2 min to complete a single time point. We provide an eN&B (and standard N&B) MATLAB software package amenable to any standard confocal or TIRF microscope. The software requires a high-RAM computer (64 Gb) to run and includes a photobleaching detrending algorithm, which allows extension of the live imaging for more than an hour

A feedback-based multi-classifier system

Multi-classifier approach is a widespread strategy used in many difficult classification problems. Traditionally, in a multi-classifier approach, a classification decision based on the combination of a multitude of classifiers is expected to outperform the decisions of each individual classifier. Therefore, in a multi-classifier systems, the potential of the whole set of classifiers is only exploited at the level of the final decision, in which the contributions of all classifiers is used by combining their individual decisions. This paper shows a feed-back based multi-classifier system in which the multi-classifier approach is used not only for providing the final decision, but also for improving the performance of the individual classifiers, by means of a closed-loop strategy. The experimental tests have been carried out in the field of hand-written numeral recognition. The result demonstrates the effectiveness of the proposed approach and its superiority with respect to traditional approach

Performance optimization of a Two-Stroke supercharged diesel engine for aircraft propulsion

In Two-Stroke engines, the cylinder filling efficiency is antithetical to the cylinder scavenging efficiency; moreover, both of them are influenced by geometric and thermodynamic parameters characterizing the design and operation of both the engine and the related supercharging system. Aim of this work is to provide several guidelines about the definition of design and operation parameters for a Two-Stroke two banks Uniflow diesel engine, supercharged with two sequential turbochargers and an aftercooler per bank, with the goal of either increasing the engine brake power at take-off or decreasing the engine fuel consumption in cruise conditions. The engine has been modeled with a 0D/1D modeling approach. Then, the model capability in describing the effect of several parameters on engine performance has been assessed comparing the results of 3D simulations with those of 0D/1D model. The validated 0D/1D model has been used to simulate the engine behavior varying several design and operation engine parameters (exhaust valves opening and closing angles and maximum valve lift, scavenging ports opening angle, distance between bottom edge of the scavenging ports and bottom dead center, area of the single scavenging port and number of ports, engine volumetric compression ratio, low and high pressure compressor pressure ratios, air/fuel ratio) on a wide range of possible values. The parameters most influencing the engine performance are then recognized and their effect on engine thermodynamic behavior is discussed. Finally, the system configurations leading to best engine power at sea level and lowest fuel consumption in cruise conditions - respectively +42% and -7% with respect to baseline - have been determined implementing a multicriteria optimization procedure