Modeling Confined Cell Migration Mediated by Cytoskeleton Dynamics

Cell migration is an important biological process that has generated increasing interest during the last several years. This process is based on three phases: protrusion at the front end of the cell, de-adhesion at the rear end and contraction of the cell body, all of them coordinated due to the polymerization/depolymerization of certain cytoskeletal proteins. The aim of this work is to present a mathematical model to simulate the actin polymerization/depolymerization process that regulates the final outcome of cell migration process, considering all the above phases, in a particular case: when the cell is confined in a microfluidic channel. Under these specific conditions, cell migration can be approximated by using one-dimensional simulations. We will propose a system of reaction-diffusion equations to simulate the behavior of the cytoskeletal proteins responsible for protrusion and contraction in the cell, coupled with the mechanical response of the cell, computing its deformations and stresses. Furthermore, a numerical procedure is presented in order to simulate the whole process in a moving and deformable domain corresponding to the cell body

Floral biology and reproductive system of Passiflora mooreana (Passifloraceae)

Three floral phases were distinguished through anthesis, which starts after 1 p.m. Flowers in phase 1 and 3 (pollen donors) had their stigmas up. Flowers in phase 2 (receptors and donors of pollen) had their stigmas recurved near the anthers. Flowers in phase 2 occurred simultaneously with others in phase 1, during the day, and also with others in phase 3 (during the night). Sugar concentration in nectar varied: it was acceptable for Hymenoptera in the afternoon (when Xylocopa spp. and Centris spp. pollinate) and for sphingids after sunset (when Erinnyis ello seems to pollinate). Passiflora mooreana is melitophilous, but also is a resource for moths in the evening. Flowers showed a low degree of autoincompatibility. The low percent of fruits obtained suggests that the great distance between plants does not favor cross-pollination. The ovary wall may grow without pollination.Fil:Amela García, M.T. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.Fil:Hoc, P.S. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina

A discrete approach for modeling cell-matrix adhesions

During recent years the interaction between the extracellular matrix and the cytoskeleton of the cell has been object of numerous studies due to its importance in cell migration processes. These interactions are performed through protein clutches, known as focal adhesions. For migratory cells these focal adhesions along with force gener- ating processes in the cytoskeleton are responsible for the for- mation of protrusion structures like lamellipodia or filopodia. Much is known about these structures: the different proteins that conform them, the players involved in their formation or their role in cell migration. Concretely, growth-cone filopo- dia structures have attracted significant attention because of their role as cell sensors of their surrounding environment and its complex behavior. On this matter, a vast myriad of math- ematical models has been presented to explain its mechan- ical behavior. In this work, we aim to study the mechani- cal behavior of these structures through a discrete approach. This numerical model provides an individual analysis of the proteins involved including spatial distribution, interaction between them, and study of different phenomena, such as clutches unbinding or protein unfolding

Reproductive aspects of the rose shrimp Parapenaeus longirostris (Lucas, 1846) in the Golf of Cadiz (southwestern Iberian Peninsula)

Parapenaeus longirostris (Lucas, 1846) is an abundant penaeid species which inhabits the Eastern Atlantic, from Portugal to Angola, and the Mediterranean Sea. This species is of great interest to fishermen in the Spanish waters of the Gulf of Cadiz. The present study on the reproductive cycle of P. longirostris was based on the analysis of monthly commercial samples and fisheries research surveys carried out in this region. This species shows two spawning peaks throughout the year, the first peak occurring in late spring and the second one in the autumn. The larger mature females mainly spawn in the spring, whereas smaller adult females spawn in autumn. Females’ cephalothorax length (CL) at first maturity was between 21.5 and 22 mm CL. In males the joining of the two sections of the petasma takes place at between 12 and 15 mm CL, being always separated at sizes lower than 11 mm CL. The size at which 50 % of males have a joint petasma was estimated at 12.9 mm CL, the size at first maturity being estimated at 14.8 mm CL. The conditioning factor is related more to growth events than to ovarian maturation, and a relationship was found between them. Relative fecundity was estimated at 7486 eggs/g of female, with fecundity ranging from 21410 to 186856 eggs. Females at the stage of both advanced ovarian development and readiness to spawn occurred at depths greater than 100 m.La gamba blanca Parapenaeus longirostris (Lucas, 1846) es un peneido abundantemente distribuido en el Atlántico oriental-desde Portugal hasta Angola-y en el Mediterráneo, y constituye un recurso primordial para un importante sector pesquero en aguas del Golfo de Cádiz. Para ampliar el conocimiento sobre su ciclo reproductivo se muestrearon mensualmente las capturas comerciales y se consideraron de nuevo muestras obtenidas en otras campañas de investigación desarrolladas en la zona. En el ciclo se distinguen dos máximos de puesta al año: el primero al final de primavera y el segundo en otoño. Las hembras más grandes realizan la puesta fundamentalmente en primavera, mientras quelas de tamaños menores lo hacen en otoño. La talla de primera madurez en las hembras se sitúa entre 21.5 y 22 mm de longitud del cefalotórax (LC). En los machos, la unión de las dos piezas del petasma tiene lugar cuando los ejemplares alcanzan entre 12 y 15 mm LC, permaneciendo aún separadas en todos los individuos de menos de 11 mm LC; la talla a la que el 50 % de los machos tiene el petasma totalmente formado fue estimada en 12.9 mm LC. La masa espermática en las coxas del quinto par de pereiópodos está presente a partir de 13 mm LC, calculándose la talla de primera madurez en 14.8 mm LC. El factor de condición está más relacionado con el crecimiento en sí que con la maduración. La fecundidad relativa fue estimada en 7486 huevos por gramo de ejemplar hembra, encontrándose valores entre 21410 y 186856 huevos. La puesta tiene lugar a partir de 100 m de profundidad

Aplicación de técnicas de análisis multicriterio a la localización óptima de extracciones de arenas y gravas en el entorno de Zaragoza

Texto resumen

Multicriteria analysis techniques for sand and gravel extraction site suitable location in the surroundings of Zaragoza

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EVALUATION OF THE COST-EFFECTIVENESS OF GRID-CONNECTED PHOTOVOLTAIC SOLAR ENERGY IN WINERIES

The objective of this study was to analyze the cost-effectiveness of photovoltaic (PV) solar energy in wineries. The factors analysed were solar radiation, cost of PV installation, prices in the public electricity grid, size of the winery, power of installed panels, influence of the decreased consumption during weekends, and seasonality in the consumption. The study has been based on the European TESLA project, in which 39 energy audits were carried out in wineries in four European countries. A winery of 30,000 hL/year was characterized as a representative winery. The results showed that seasonality was key in the profitability of the system for self-consumption, related to the optimum power to be installed of PV. It was recommended to install, as an optimal PV power, the stable electrical power that is demanded in the daytime period. Optimizing the installed power of PV panels in the representative winery, the percentage of electrical energy consumption covered by photovoltaic energy varied between 16% and 22%. The percentage of the cost of electric energy covered varied between 18% and 24%, with payback values between 18 years (3.1 peak sun hours of solar radiation -PSH) and 10 years (5.6 peak sun hours of solar radiation - PSH). All the factors involved were analyzed

The role of innovation labs in advancing the relevance of Public Service Media: the cases of BBC News Labs and RTVE Lab

As part of their social function, Public Service Media (PSM) organizations are devoted to innovation. In this context, a number of European PSM outlets have created laboratories based on the implementation of products, services and formats for multiplatform audiences. Our research focused on two case studies: a) BBC News Labs (UK) and b) RTVE Lab (Spain). We applied both quantitative and qualitative methodologies. We used content analysis techniques to examine products generated by the two laboratories between 2013 and 2017, quantifying and classifying each one according to categories related to the type and nature of the innovation. We carried out ethnographic research using participant observation over five days in each laboratory, both in London and Madrid. We also conducted open-ended interviews with five professionals at the BBC and three at RTVE, as well as with the head of EBU’s Media Strategy & Development department. Our results show that BBC News Labs implements a global innovation strategy through the design and engineering of products that facilitate journalists’ work. Projects include speechto- text software, prototypes for voice recognition and text analysis, chatbots and object-based media. On the other hand, RTVE Lab focuses on designing and producing interactive formats, multimedia narratives and social media content, with an emphasis on experimentation. The findings reveal the main barriers and incentives to innovation within each lab and show how the transfer of innovation could increase the diversity, universality and quality of their overall output

El cine y la risa en el teatro de Jardiel Poncela

La obra de Enrique Jardiel Poncela ofrece un universo literario cargado de intuiciones modernas. El cinematógrafo se incorpora pronto a sus referencias artísticas y su poética deja una huella indeleble en su dramaturgia. El ensayo se propone el análisis de esta influencia a través de dos de sus propuestas más paradigmáticas, 'Los ladrones somos gente honrada' y 'Los habitantes de la casa deshabitada', en el teatro y en la diversa fortuna que corrieron las distintas versiones que se llevaron al cine. Enrique Jardiel Poncela's works present a literary universe plenty of modern intuitions. The cinematograph is early incorporated by the author to his artistic references and its Poetics leave a deep trace in his dramaturgy. This essay finds that influence in two paradigmatic plays. 'Los ladrones somos gente honrada' and 'Los habitantes de la casa deshabitada', in both theater and cinematic versions