Evolvability of feed-forward loop architecture biases its abundance in transcription networks

Background: Transcription networks define the core of the regulatory machinery of cellular life and are largely responsible for information processing and decision making. At the small scale, interaction motifs have been characterized based on their abundance and some seemingly general patterns have been described. In particular, the abundance of different feed-forward loop motifs in gene regulatory networks displays systematic biases towards some particular topologies, which are much more common than others. The causative process of this pattern is still matter of debate. Results: We analyzed the entire motif-function landscape of the feed-forward loop using the formalism developed in a previous work. We evaluated the probabilities to implement possible functions for each motif and found that the kurtosis of these distributions correlate well with the natural abundance pattern. Kurtosis is a standard measure for the peakedness of probability distributions. Furthermore, we examined the functional robustness of the motifs facing mutational pressure in silico and observed that the abundance pattern is biased by the degree of their evolvability. Conclusions: The natural abundance pattern of the feed-forward loop can be reconstructed concerning its intrinsic plasticity. Intrinsic plasticity is associated to each motif in terms of its capacity of implementing a repertoire of possible functions and it is directly linked to the motif's evolvability. Since evolvability is defined as the potential phenotypic variation of the motif upon mutation, the link plausibly explains the abundance pattern.This work was supported by the EU grant CELLCOMPUT, the EU 6th Framework project SYNLET (NEST 043312), the James McDonnell Foundation, the Marcelino Botín Foundation, the University of Vienna and by the Santa Fe Institut

Synthetic Turing protocells: vesicle self-reproduction through symmetry-breaking instabilities

The reproduction of a living cell requires a repeatable set of chemical events to be properly coordinated. Such events define a replication cycle, coupling the growth and shape change of the cell membrane with internal metabolic reactions. Although the logic of such process is determined by potentially simple physico-chemical laws, the modeling of a full, self-maintained cell cycle is not trivial. Here we present a novel approach to the problem which makes use of so called symmetry breaking instabilities as the engine of cell growth and division. It is shown that the process occurs as a consequence of the breaking of spatial symmetry and provides a reliable mechanism of vesicle growth and reproduction. Our model opens the possibility of a synthetic protocell lacking information but displaying self-reproduction under a very simple set of chemical reactions

Spatial ecology of the Red Kite (Milvus milvus) during the breeding period in Spain

Studies focusing on the spatial ecology of the Red Kite (Milvus milvus) during the breeding season are scarce, despite this season having major importance in its conservation. Spain has one of the largest breeding populations of this species, but it is very threatened in this country. Here, 28 Red Kites were tagged in Spain with GPS satellite transmitters to study the movements of breeding adults during the breeding season (March-June), evaluating the differences according to sex, and investigating the habitat selection. The area used by females was smaller than the used by males (95% KDE = 4.48 vs. 3.30 km2). Females also traveled less distance per hour and remained closer to the nest. Thus, females had a higher frequency of locations at distances 1 km. Distances recorded at >5 km were scarce for both sexes, and maximum distances reached were usually (61% of seasons) less than 15 km. Both sexes increased the frequency of movements between 1–3 km during the central hours of the day. Red Kites mainly used areas occupied by non-irrigated arable land, forests, scrubs, and herbaceous vegetation. The selection of certain types of crops highlights the importance of the agroforestry landscape for the conservation of the species. On the other hand, we documented for the first time how part of the Spanish breeding population is a short-distance migrant within the Iberian Peninsula while other part of the population makes post-breeding movements during summer

Seasonal differences in migration strategies of Red Kites (Milvus milvus) wintering in Spain

Red Kite shows a great variability in its migration strategies: most individuals in north-eastern Europe are migrants, but there is also a growing number of sedentary individuals. Here, we tagged 49 Red Kites wintering in Spain with GPS/satellite transmitters between 2013 and 2020 to study the autumn and spring migration between the breeding or summering areas in Central Europe and the wintering quarters in Spain. In first place, differences between immatures and adults were found for spring migration. Adults began the spring migration towards the northeast in February–March while the immature individuals began to migrate significantly later and showing a wider date range (February-June). Adults also takes significantly less days to arrive at their destinations (12 ± 5 days) and cover more distance per day (134.2 ± 37.1 km/day) than immatures (19 ± 11 days and 98.9 ± 21.2 km/day). In second place, we also found differences between spring and autumn migration (excluding immatures). Spring migrations were clearly faster and with less stopovers days than autumn migrations. Autumn migration began between mid-October and late November and two different behaviours were observed: most birds made a quick migration direct to the wintering areas with only some days of stopovers, but others prolonged the migration with long stops along the route. These results highlight a great variation in the migratory movements of Red Kite, not only according to age but also between individuals and seasons.Funding for the tagging was provided by Fundación Iberdrola España, Gobierno del País Vasco, Fundación Biodiversidad, Grupo Ornitológico SEO-Monticola, FAB and Binaced townhall. NorthStar donated two GPS-GSM prototype units to deploy on Kites. J. Vidal-Mateo is supported by a FPU grant of Spanish Ministry of Education (reference FPU014/04671)

Adaptando OpenCA para implementar una PKI para e-Science

En el presente artículo se describe la experiencia obtenida en la implementación de una PKI, que emitirá certificados de usuario, de host y de servicio para proyectos de E-science, utilizando OpenCA.\nSe detallan aquí las ventajas ofrecidas por OpenCA así como los puntos débiles que este software presenta en el momento de poner en marcha la PKI. Se presentan además otros puntos relevantes relacionados con la instalación y configuración de la misma.I Workshop de Arquitecturas, Redes y Sistemas Operativos (WARSO

Arquitectura de sensores de seguridad para la correlación de eventos

El crecimiento exponencial que tuvo Internet en la última década trajo consigo un gran volumen de tráfico hostil. Es por ésto que implementar mecanismos de seguridad es una tarea imprescindible del administrador de red actual. Además el monitoreo de la seguridad de una red y sus sistemas es una pieza fundamental en la segurización de la misma puesto que permite una detección temprana de los incidentes de seguridad, para así responder en tiempo y forma y consecuentemente elaborar contramedidas a futuro.\nAlgunas aproximaciones más complejas consideran la sincronización de eventos de seguridad con una posterior correlación de tales eventos, con el objeto de obtener alertas más confiables. Una iniciativa de tal proyecto es el llevado a cabo por el ARCERT, llamada CAL “Coordinación y Análisis de Logs”, el cual prevee la sincronización de eventos de seguridad dentro de las redes de los Organismos de la Administración Pública Nacional. Otra iniciativa similar es la de la UNAM, mediante el proyecto llamado Honeynet UNAM, el cual se basa en el uso de honeynets dentro del campus de la Universidad para el análisis de eventos de seguridad y la implementación de mecanismos pro-activos.\nEn este trabajo se presenta una arquitectura de sensores de seguridad distribuidos estratégicamente, de modo de proveer la información recolectada a un monitor central en el que se lleven a cabo correlaciones de datos que permitan generar alertas confiables.Eje: Agentes, Redes y Sistemas Operativo

Cuando la seguridad trasciende las fronteras o sobre como manejar el problema de la autenticación para el acceso internacional de recursos distribuidos

Como ocurrió con Internet, una vez más es la ciencia la que inicia el camino de nuevas tecnologías. La necesidad de ejecutar aplicaciones que requieren una gran capacidad de procesamiento, condujo tanto al afianzamiento de las tecnologías GRID, como a la creación de organismos internacionales que cumplan tareas de autenticación para aquellas entidades finales que quieran acceder (o ejecutar) estas aplicaciones.\nEstas comunidades científicas, que trascienden fronteras, han tenido que desarrollar un lenguaje común, adaptarse a pautas de organización e intercambio que exigen la definición de un marco de interoperabilidad donde la seguridad juega un rol trascendental.\nSi se repite el modelo de Internet, donde lo que comenzó en el mundo científico/académico hoy está incorporado a la cotidianeidad de la mayoría de la población mundial, conceptos tales como la identidad federada, autenticación a través de dominios, protocolos genéricos para servicios colectivos, organizaciones virtuales, single sign-on, deben estar en la agenda y en las líneas de trabajo de aquellos que quieren estar al tanto de las exigencias tecnológicas actuales.Eje: Arquitectura, redes y sistemas operativo

Striking Variability in the Post-Reproductive Movements of Spanish Red Kites (Milvus milvus): Three Strategies, Sex Differences, and Changes over Time

It was assumed that the Spanish breeding population of the red kite (Milvus milvus) was resident, hence their movements were restricted to their breeding area for their entire lifecycle. However, recent observations indicated that the post-reproductive strategies of the red kite in Spain are more diverse. We tagged 47 breeding adult red kites in Spain and analyzed their movements during the post-reproductive period (July–February). We found three strategies in the population: migration (10%), sedentarism (70%), and sedentarism with post-reproductive movements (20%), based on seasonality and other movement parameters. Sedentarism with post-reproductive movements was a very variable strategy that involved all-direction wandering movements far away from the nest (up to 589 km) after breeding season, and then a returned journey toward the starting point in time for the next breeding season. Our results also suggest that sedentarism with post-reproductive movements is much more common in females than males. Furthermore, 17% of the individuals changed their strategy over the years. This study highlights the great individual variability and plasticity of the red kite and allows for a better understanding of spatial ecology in opportunistic raptors

Cogeneración en Chile: capacidades, desarrollo y perspectivas

En Chile, el proyecto de cogeneración más antiguo data de 1930 y operó hasta el año 1997. Sin embargo, pese a que la tecnología lleva introducida largo tiempo, pocos son los estudios que han analizado el potencial de CHP y su evolución. Un primer paso para el estudio del potencial del país es la creación de un catastro que incluya la capacidad instalada. El interés de este ejercicio radica en el potencial de integración de mayores cantidades de CHP en el sistema eléctrico con el objetivo de hacer frente a la intermitencia de fuentes de energía no convencionales. Además, las plantas CHP pueden ayudar a alcanzar los objetivos de eficiencia energética gracias a la posibilidad de los generadores de volcar a la red tanto la electricidad como calor no consumido en los procesos productivos. Sin embargo, para que esto ocurra es necesario el desarrollo de un marco regulatorio acorde a las capacidades y características de las plantas de CHP. El objetivo de este artículo es precisamente identificar las características de las instalaciones en industrias específicas, así como su evolución, con el objetivo de extrapolar los datos al resto de la economía y obtener un potencial de CHP para el país. Para ello, se han hecho consultas de catastros anteriores, así como entrevistas con empresas para conocer el estado actual del parque de plantas de CHP en el país.1997. However, although the CHP technology has been introduced for a long time, few studies have analysed its potential and evolution. The development of a cadastre that includes all installed capacity and their characteristics is the first step to analyse the country's potential. The importance of this exercise lies in the potential integration of greater CHP capacities in the electric system as a mean to address the intermittence of non-conventional energy sources. In addition, due to the possibility to transfer both the electricity and heat not consumed in the production processes into the grid, CHP plants can help achieve energy efficiency objectives. However, for this to happen it is necessary the availability of a regulatory framework designed according to the capacities and characteristics of the CHP capacities installed. This article aims to identify the characteristics of the CHP capacities in specific industries as well as their evolution during time, in order to extrapolate the data to the rest of the economy and obtain a CHP potential for the country. For this purpose, previous cadastres have been consulted and the information complemented with interviews with companies to know the current status of the CHP plants in the country.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES

Evolutionary algorithm for the optimization of meal intake and insulin administration in patients with type 2 diabetes

The optimal management of type 2 diabetes (T2DM) is complex and involves an appropriate combination of diet, exercise, and different pharmacological treatments. Artificial intelligence-based tools have been shown to be very useful for the diagnosis and treatment of diverse pathologies, including diabetes. In the present study, we present a proof of concept of the potential of an evolutionary algorithm to optimize the meal size, timing and insulin dose for the control of glycemia. We found that an appropriate distribution of food intake throughout the day permits a reduction in the insulin dose required to maintain glycemia within the range recommended by the American Diabetes Association for patients with T2DM of a range of severities. Furthermore, the effects of restrictions to both the timing and amount of food ingested were assessed, and we found that an increase in the amount of insulin was required to control glycemia as dietary intake became more restricted. In the near future, the use of these computational tools should permit patients with T2DM to optimize their personal meal schedule and insulin dose, according to the severity of their diabetes