Colicin S8 export: extracellular and cytoplasmic colicin are different

The properties of colicin S8 are different for the cytoplasmic, periplasmic and extracellular protein. Interactions with its specific receptors reflect this. Active cell extracts separate into a non-anionic along with an anionic fraction by DEAE-Sephacell chromatography. Previously, we have purified cell-associated colicin S8 as an aggregation of highly related polypeptides; cytoplasmic colicin S8 seems to be post-translationally processed into an aggregation of polypeptides of molecular mass ranging from 45,000 Da to 60,000 Da. We suggest that a conformational change to colicin S8 may occur related to the export process

The purified colicin S8 is a multimeric protein

Bacteriocins have been isolated both as simple proteins and as proteins in association with carbohydrates, lipids, etc. Colicins are commonly inducible and extracellular. Their molecular masses range from 30 to 90 kDa. Pure colicin S8 was obtained in three steps from supernatant of induced cells: (i) Ammonium sulfate precipitation; (ii) anion exchange chromatography; and (iii) phenyl-Sepharose hydrophobic chromatography, either by preparative or fast performance liquid chromatography (FPLC) analytical purification procedure. In our hands, purified colicin S8 was an aggregation of extremely related polypeptides. Composition of those active fractions was the same: five polypeptides of molecular weight around 55 kDa. Behavior on molecular filtration indicated a molecular weight higher than 200 kDa. Similar results were obtained when purification was carried out through FPLC. Producing strains contain a single plasmid that encodes colicin S8; in minicells, this plasmid was shown to specify a 60 kDa polypeptide. We conclude that more than one form of colicin S8 exists. The forms are structurally related and can be recognized by antibodies raised against one of the polypeptides. Consistent with this conclusion, comparison of peptides produced after hydrolysis with chlorosuccinamide indicated that the active proteins contained both shared and unique components

Potenziale del metodo Service-Learning per la promozione della cittadinanza e l’educazione del carattere

Promuovere la cittadinanza nelle società odierne significa rafforzare quegli aspetti del carattere delle persone che consentiranno loro di comportarsi in modo responsabile e attivo e di essere coinvolti nel raggiungimento del bene comune. Riteniamo che la principale difficoltà che si trova oggi nell’educazione civica sia la mancanza di etica. Imparare ad essere un buon cittadino è un compito che dura tutta la vita e una saggezza pratica che non richiede solo intelligenza per riconoscere quali tratti migliorano la nostra vita nella società, ma anche la volontà di praticarli. L’educazione del carattere è un modo di comprendere e identificare l’educazione morale. Mira a riaffermare la dimensione etica inevitabile dell’educazione. L’idea di poter educare il carattere delle persone è antica e risale ai tempi della Grecia classica. Ma anche nella nostra società più attuale abbiamo dei punti di riferimento validi. Negli anni Ottanta e Novanta, ad esempio, il concetto di etica della virtù ha ricevuto un grande impulso ed è diventato la base per una buona educazione del carattere contemporaneo. Non è un caso che l’educazione del carattere sia diventata così importante negli ultimi anni, specialmente nel mondo di lingua inglese, parallelamente a una diffusione del metodo Service-Learning.Promoting citizenship in present-day societies means reinforcing those aspects of people’s characters which will allow them to behave responsibly and actively and be involved in achieving the common good. We believe that the main difficulty to be found in civic education nowadays is a lack of ethics. Learning to be a good citizen is a lifelong task and practical wisdom which not only demands intelligence to recognize which traits improve our life in society but also the will to practice them. Character education is a way of understanding and identifying moral education. It aims to reaffirm the inescapable ethical dimension of education. This proposal has its origins in classical Greece, but it was not until the 1980s and 90s that the ethics of virtue received a great boost and became the basis for a good deal of contemporary character education. It is not by chance that character education has grown so much in importance over the last few years, especially in the English-speaking world, in parallel with an increase in Service-Learning methodology

Modelos y sistemas dinámicos

En este texto se recogen las materias que, durante cinco años, han sido impartidas por los autores en la asignatura "Modelos y Sistemas Dinámicos" de la licenciatura de Ciencias del Mar de Ila Universidad de Cádi

Metodología de selección de procesos para la gestión de servicios en las pymes

It is a fact that more and more companies operations lay in information and communication technologies (ICT). Traditional management models need to be adapted to this new reality. That is why some initiatives are emerging (COBIT [control objectives for information and related technology], CMMI [capability maturity model integration], ITIL [information technology infrastructure library], etc.) which pretend to guide about the processes, metrics and technology management indicators most suitable. This document focuses in ITIL, that is the best representation of what has been called IT Governance. ITIL is a reference in technology services companies and in ICT departments of any company. That is due to the high level of utility provided by the organization and coverage of the processes proposed. Implantation of a management model based in ITIL processes forces companies to a relevant decision: which processes should be implemented?, which one should be the first one?, etc. The answer to this and other questions is not easy because the adoption of these processes implies an economical investment. This article shows an approach to the implementation order so we can optimize the position of the company in front of the competence in its sector, in front of similar sized companies or any other parameter we could define.Es un hecho que cada vez más empresas basan su operativa en las tecnologías de la información y las comunicaciones (TIC). Los modelos de gestión tradicionales necesitan ser adaptados a esta nueva realidad. Para ello están surgiendo iniciativas (COBIT [control objectives for information and related technology], CMMI [capability maturity model integration], ITIL [information technology infrastructure library], etc.) que pretenden orientar sobre los procesos, las métricas y los indicadores de gestión de la tecnología más adecuados. En este trabajo nos centraremos en ITIL, máximo exponente de lo que se ha dado en llamar Gobierno TI. ITIL es un referente en las empresas de servicios de tecnología y en los departamentos de TIC de cualquier empresa. Ello se debe a que la organización y cobertura de los procesos propuestos para la correcta gestión de servicios informáticos aporta un grado de utilidad superior al resto de iniciativas existentes. La implantación de un modelo de gestión basado en los procesos ITIL supone para las empresas una decisión relevante: ¿qué procesos implantar?, ¿por cuál empezar?, etc. La contestación a estas y otras preguntas no es fácil porque la adopción de estos procesos implica una inversión económica importante. Este trabajo da respuesta a la pregunta de qué orden de implantación de procesos seguir de modo que maximicemos el posicionamiento de la empresa en su sector, el posicionamiento frent

Low Energy Physical Activity Recognition System on Smartphones

An innovative approach to physical activity recognition based on the use of discrete variables obtained from accelerometer sensors is presented. The system first performs a discretization process for each variable, which allows efficient recognition of activities performed by users using as little energy as possible. To this end, an innovative discretization and classification technique is presented based on the 2 distribution. Furthermore, the entire recognition process is executed on the smartphone, which determines not only the activity performed, but also the frequency at which it is carried out. These techniques and the new classification system presented reduce energy consumption caused by the activity monitoring system. The energy saved increases smartphone usage time to more than 27 h without recharging while maintaining accuracy.Ministerio de Economía y Competitividad TIN2013-46801-C4-1-rJunta de Andalucía TIC-805

An adaptive methodology to discretize and select features

A lot of significant data describing the behavior or/and actions of systems can be collected in several domains. These data define some aspects, called features, that can be clustered in several classes. A qualitative or quantitative value for each feature is stored from measurements or observations. In this paper, the problem of finding independent features for getting the best accuracy on classification problems is considered. Obtaining these features is the main objective of this work, where an automatic method to select features is proposed. The method extends the functionality of Ameva coefficient to use it in other tasks of machine learning where it has not been defined.Ministerio de Ciencia e Innovación ARTEMISA TIN2009-14378-C02-01Junta de Andalucia Simon TIC-805

Mobile activity recognition and fall detection system for elderly people using Ameva algorithm

Currently, the lifestyle of elderly people is regularly monitored in order to establish guidelines for rehabilitation processes or ensure the welfare of this segment of the population. In this sense, activity recognition is essential to detect an objective set of behaviors throughout the day. This paper describes an accurate, comfortable and efficient system, which monitors the physical activity carried out by the user. An extension to an awarded activity recognition system that participated in the EvAAL 2012 and EvAAL 2013 competitions is presented. This approach uses data retrieved from accelerometer sensors to generate discrete variables and it is tested in a non-controlled environment. In order to achieve the goal, the core of the algorithm Ameva is used to develop an innovative selection, discretization and classification technique for activity recognition. Moreover, with the purpose of reducing the cost and increasing user acceptance and usability, the entire system uses only a smartphone to recover all the information requiredMinisterio de Economía y Competitividad HERMES TIN2013-46801-C4-1-rJunta de Andalucía Simon P11-TIC-8052Junta de Andalucía M-Learning P11-TIC-712

Activity Recognition System Using AMEVA Method

This article aims to develop a minimally intrusive system of care and monitoring. Furthermore, the goal is to get a cheap, comfortable and, especially, efficient system which controls the physical activity car ried out by the user. For this purpose an innovative approach to physical activity recognition is presented, based on the use of discrete variables which employ data from accelerometer sensors. To this end, an innova tive discretization and classification technique to make the recognition process in an efficient way and at low energy cost, is presented in this work based on the χ2 distribution. Entire process is executed on the smartphone, by means of taking the system energy consumption into ac count, thereby increasing the battery lifetime and minimizing the device recharging frequency.Ministerio de Economía y Competitividad TIN2009-14378-C02-01 (ARTEMISA)Junta de Andalucía TIC-8052 (Simon

Discrete techniques applied to low-energy mobile human activity recognition. A new approach

Human activity recognition systems are currently implemented by hundreds of applications and, in recent years, several technology manufacturers have introduced new wearable devices for this purpose. Battery consumption constitutes a critical point in these systems since most are provided with a rechargeable battery. In this paper, by using discrete techniques based on the Ameva algorithm, an innovative approach for human activity recognition systems on mobile devices is presented. Furthermore, unlike other systems in current use, this proposal enables recognition of high granularity activities by using accelerometer sensors. Hence, the accuracy of activity recognition systems can be increased without sacrificing efficiency. A comparative is carried out between the proposed approach and an approach based on the well-known neural networks.Junta de Andalucia Simon TIC-805