437 research outputs found

    Estudio de diversas especies de los géneros Trachelomonas y Strombomonas (Euglenophyta).

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    Se estudian siete especies de Euglenofíceas loricadas, 2 pertenecientes al género Strombomonas y5 de Trachelomonas. Se analiza la microarquitectura de la lórica a microscopio óptico y electrónico de barrido, describiendo los elementos ornamentales de cada especie.Destacamos el estudio de tres poblaciones de Trachelomonas, dos de ellas incluidas provisionalmente en T. nigra y T. similis respectivamente, mientras que en la tercera: Trachelomonas sp., con una gran variabilidad morfológica de la lórica, destaca la existencia de un anillo de perforaciones que se disponen alrededor del poro flagelarSeven species of Euglenophyceae with lorica (2 Strombomonas and 5 Trachelomonas) haven been studied. We analyzed their lorica microarchitecture by means of ligh microscopy and scanning electron microscopy, enumerating their different ornamental elements. We stand out the study of three population of Trachelomonas, two of them are provisionally included in T. nigra and T. similis respectively. The third one: Trachelomonas sp. show a large morphological variability with only one common ornamental character within of the population: a ring of perforations around the flagellum pore

    TBT e imposex en Galicia: los efectos de un disruptor endocrino en poblaciones de gasterópodos marinos

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    En este artículo se resume la experiencia de nuestro grupo de investigación en el campo de los efectos de un disruptor endocrino androgenizante (el tributilo de estaño, más conocido como TBT por su abreviatura del inglés tributyltin) en gasterópodos marinos del litoral gallego. Nuestras investigaciones sobre este tema comenzaron en 1996 y continúan en la actualidad. Después de una breve introducción sobre qué es el TBT y su problemática, se resumen los principales hallazgos conseguidos con nuestro trabajo, que se basan principalmente en el estudio de los efectos en el gasterópodo carnívoro Nucella lapillus con alguna información adicional para otras especies como el carroñero Nassarius reticulatus. Nuestro trabajo abarca tanto la bioacumulación de contaminante, la manifestación de un biomarcador específico de los efectos del TBT (masculinización de hembras, conocido como imposex) en poblaciones naturales y en experiencias de trasplante, el estudio de la presencia de individuos genéticamente más resistentes a los efectos del TBT y algunos datos de ecología molecular sobre la estructuración poblacional y capacidad de dispersión de Nucella lapillus

    Extending the VEF traces framework to model data center network workloads

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    Producción CientíficaData centers are a fundamental infrastructure in the Big-Data era, where applications and services demand a high amount of data and minimum response times. The interconnection network is an essential subsystem in the data center, as it must guarantee high communication bandwidth and low latency to the communication operations of applications, otherwise becoming the system bottleneck. Simulation is widely used to model the network functionality and to evaluate its performance under specific workloads. Apart from the network modeling, it is essential to characterize the end-nodes communication pattern, which will help identify bottlenecks and flaws in the network architecture. In previous works, we proposed the VEF traces framework: a set of tools to capture communication traffic of MPI-based applications and generate traffic traces used to feed network simulator tools. In this paper, we extend the VEF traces framework with new communication workloads such as deep-learning training applications and online data-intensive workloads.Ministerio de Ciencia e Innovación y Agencia Estatal de Investigación (MCIN/AEI/10.13039/501100011033) R &D Project Grant (PID2019-109001RA-I00)Publicación en abierto financiada por el Consorcio de Bibliotecas Universitarias de Castilla y León (BUCLE), con cargo al Programa Operativo 2014ES16RFOP009 FEDER 2014-2020 DE CASTILLA Y LEÓN, Actuación:20007-CL - Apoyo Consorcio BUCL

    Early morning fluctuations in trunk diameter are highly sensitive to water stress in nectarine trees

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    The sensitivity to water stress of different plant water status indicators was evaluated during two consecutive years in early nectarine trees grown in a semi-arid region. Measurements were made post-harvest and two irrigation treatments were applied: a control treatment (CTL), irrigated at 120 % of crop evapotranspiration demand to achieve non-limiting water conditions, and a deficit irrigation treatment, that applied around 37 % less water than CTL during late postharvest. The plant water status indicators evaluated were midday stem water potential (Ψ stem) and indices derived from trunk diameter fluctuations: maximum daily shrinkage (MDS), trunk daily growth rate, early daily shrinkage measured between 0900 and 1200 hours solar time (EDS), and late daily shrinkage that occurred between 1200 hours solar time and the moment that minimum trunk diameter was reached (typically 1600 hours solar time). The most sensitive [highest ratio of signal intensity (SI) to noise] indices to water stress were Ψ stem and EDS. The SI of EDS was greater than that of Ψ stem, although with greater variability. EDS was a better index than MDS, with higher SI and similar variability. Although MDS was linearly related to Ψ stem down to −1.5 MPa, it decreased thereafter with increasing water stress. In contrast, EDS was linearly related to Ψ stem, although the slope of the regression decreased as the season progressed, as in the case of MDS. Further studies are needed to determine whether EDS is a sensitive index of water stress in a range of species.This research was supported by the Spanish Ministry of Science of Innovation (AGL2010-19201-C04-04), European project SIRRIMED (FP7-KBBE-2009-3-245159) and also by the Regional Science Agency of Murcia Region (08845/PI/08). We thank E. Fereres for editorial comments

    Un enfoque de optimización para costos de inventario en modelos de inventario probabilísticos: Un caso de estudio

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    Inventories represent stocks of goods necessary for operations of sales or manufacturing in a company. These allow to the companies meet their sales levels, while representing an opportunity to the cost control and the decision-making. This paper presents an optimization approach to minimize the inventory costs in probabilistic inventory models of independent demand. The approach has been validated for set the policy optimal of inventories with probabilistic demand within a company that markets disposable products. The established policy aims to minimize the inventory costs by using the standard deviation of the historical data, the mean deviation of forecast errors and the mean deviation of the historical data. For the determination of the economic order quantities, three types of products were selected, taking historical sales data. Likewise, different forecasting methods were used, selecting the one that minimizes the mean squared error for the forecasted demand. The proposed methodology is practical and easy to use in companies where inventories have probabilistic and independent demand. Also, the proposed approach allowed optimize the costs related to holding costs, ordering costs and safety stock costs.Los inventarios representan la existencia de mercancías necesarias para las operaciones de ventas o fabricación en una empresa. Estos permiten a las empresas cumplir con sus niveles de ventas, al tiempo que representan una oportunidad para el control de costos y la toma de decisiones. Este documento presenta un enfoque de optimización para minimizar los costos de inventario en modelos de inventario probabilísticos de demanda independiente. El enfoque ha sido validado para establecer la política óptima de inventarios con demanda probabilística dentro de una empresa que comercializa productos desechables. La política establecida tiene como objetivo minimizar los costos de inventario utilizando la desviación estándar de los datos históricos, la desviación media de los errores de pronóstico y la desviación media de los datos históricos. Para la determinación de la cantidad económico de pedido, se seleccionaron tres tipos de productos tomando datos históricos de ventas. Asimismo, se utilizaron diferentes métodos de pronóstico, seleccionando el que minimiza el error cuadrático medio para la demanda pronosticada. La metodología propuesta es práctica y de fácil uso en empresas donde los inventarios tienen una demanda probabilística e independiente. Además, el enfoque propuesto permitió optimizar los costos relacionados con los costos de mantenimiento, los costos de pedido y los costos de inventario de seguridad

    A GSK-3b modulator delays photoreceptor cell death and preserves visual function in the rd10 mouse model of retinitis pigmentosa

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    1 p.Retinitis pigmentosa (RP) is a heterogeneous group of inherited retinal dystrophies that lead to blindness. Photoreceptor cell death, reactive gliosis and retinal inammation are common features in animal models of the disease. The enzyme Glycogen Synthase Kinase-3 Beta (GSK-3b) is involved in inammatory processes associated to diverse neurodegenerative pathologies. The aim of our study is to test in the rd10 mouse whether the GSK-3b inhibitor VP3.15 (a small heterocyclic molecule) is a potential therapeutic treatment for RP.SAF2013-41059-RPeer reviewe

    Verbal Memory and IQ Predict Adaptive Behavior in Children and Adolescents with High-Functioning Autism Spectrum Disorders

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    Adaptive deficits are commonly found in high functioning autism spectrum disorders (HF-ASD) despite of cognitive potential. Most studies have focused on the relationships between adaptive behavior and intellectual quotient (IQ) and have used correlations to study relationships between them. Few studies have analyzed cognitive variables other than IQ as potential predictors of adaptive behavior in HF-ASD using regression methods. This study aimed to analyze the impact of several cognitive variables on adaptive behavior in a sample of children and adolescents with HF-ASD. METHODS: Sample included 16 child and adolescent boys with HF-ASD (age between 7-17 years). Cognitive assessment included measures of general intelligence, visual memory, verbal memory, working memory and problem solving/flexibility tests. Vineland Adaptive Behavior Scales (VABS) was used to evaluate adaptive behavior. To establish the predictive capacity of the cognitive variables for adaptive functioning, linear regression models were fitted for each adaptive domain using a stepwise method. RESULTS: Verbal memory and IQ emerged as the main independent predictors for VABS adaptive scores. The 41% of the variance in Communication was predicted by IQ. The 35% of the variance in Daily Living Skills was predicted by verbal memory. Almost half of the variance in Socialization was predicted by both, verbal memory and IQ (49%). No other cognitive functions were associated with adaptive scores. CONCLUSIONS: The results highlight the strong impact of IQ and verbal memory on adaptive behavior in HF-ASD patients. These findings could contribute to identify potential targets of intervention

    Intravitreal injection of proinsulin-loaded microspheres delays photoreceptor cell death and vision loss in the rd10 mouse model of retinitis pigmentosa

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    9 p.-6 fig.PURPOSE. The induction of proinsulin expression by transgenesis or intramuscular gene therapy has been shown previously to retard retinal degeneration in mouse and rat models of retinitis pigmentosa (RP), a group of inherited conditions that result in visual impairment. We investigated whether intraocular treatment with biodegradable poly (lactic-co-glycolic) acid microspheres (PLGA-MS) loaded with proinsulin has cellular and functional neuroprotective effects in the retinaMETHODS. Experiments were performed using the Pde6brd10 mouse model of RP. Methionylated human recombinant proinsulin (hPI) was formulated in PLGA-MS, which were administered by intravitreal injection on postnatal days (P) 14 to 15. Retinal neuroprotection was assessed at P25 by electroretinography, and by evaluating outer nuclear layer (ONL) cellular preservation. The attenuation of photoreceptor cell death by hPI was determined by TUNEL assay in cultured P22 retinas, as well as Akt phosphorylation by immunoblottingRESULTS. We successfully formulated hPI PLGA-MS to deliver the active molecule for several weeks in vitro. The amplitude of b-cone and mixed b-waves in electroretinographic recording was significantly higher in eyes injected with hPI-PLGA-MS compared to control eyes.Treatment with hPI-PLGA-MS attenuated photoreceptor cell loss, as revealed by comparing ONL thickness and the number of cell rows in this layer in treated versus untreated retinas. Finally, hPI prevented photoreceptor cell death and increased AktThr308 phosphorylation in organotypic cultured retinas.CONCLUSIONS. Retinal degeneration in the rd10 mouse was slowed by a single intravitreal injection of hPI-PLGA-MS. Human recombinant proinsulin elicited a rapid and effective neuroprotective effect when administered in biodegradable microspheres, which may constitute a future potentially feasible delivery method for proinsulin-based treatment of RP.Supported by Grants from the Spanish Ministerio de Ciencia e Innovacion (MICINN) and Spanish Ministerio de EconomÍa y Competitividad (MINECO), SAF2010-21879 (EJdlR and PdlV), SAF2013-41059-R (FdP and EJdlR), and technical personnel support from CIBERDEM, ISCIII, Madrid, SpainPeer reviewe

    Exploring the use of blockchain in resource-constrained fog computing environments

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    Fog computing has become a complementary technology to cloud computing and addresses some of the cloud computing threats such as the response time and network bandwidth demand. Fog computing successes processing data and storing data near to the edge, and usually is combined with container virtualization to provide hardware isolation. Empowered by these capabilities, numerous Internet of Things (IoT) applications are developed as virtualized instances on resource-constrained fog nodes such as single-board computers (SBC). In addition, blockchain has emerged as a key technology that is transforming the way we share information. Blockchain technology represents a decentralised, distributed, and immutable database ledger and is a potential solution for the distributed ecosystem of IoT applications. The distributed structure of blockchain is naturally suitable for IoT applications. However, it introduces new challenges related to CPU overhead or response time. This paper proposes a layered architecture that integrates blockchain technology and OS-level virtualization technology to develop fog-based IoT applications. It also provides insights for future deployments through a proof-of-concept use case harnessing SBCs, in this case Raspberry Pi, as blockchain-enabled fog nodes to drive virtualized IoT applications. The study shows that the maximum CPU overhead added by a permissioned blockchain based on Ethereum on the Raspberry Pi is around a 25% under stress situations while the overhead introduced by the sealer process is negligible. These results support the feasibility of using blockchain on resource-constrained fog nodes for supporting IoT applications

    Long-term impact of deficit irrigation on the physical quality of berries in ‘Crimson Seedless’ table grapes

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    A 3-year study examined the effects of DI strategies on some physical quality attributes of ‘Crimson Seedless’ table grape following harvest, after 28 days of cold storage at 0ºC and after an additional shelf life period of 3 d at 15ºC. Control vines were irrigated to ensure non-limiting water conditions (110% of crop evapotranspiration, ETc), whereas RDI and PRD treatments received 35% less water during post-veraison. The null irrigation treatment (NI) only received natural precipitation (72 % less water than the Control). Total yield and physical quality at harvest were not significantly affected by RDI or PRD. Only the NI treatment, with the worst sensory scores, decreased berry size. After cold storage, increased berry shattering within the PRD treatment was correlated with the lower ABA at the time of harvest. Neither RDI nor PRD had a significant effect on berry quality at the end of cold storage and retail period. Sensory results were similar in RDI and PRD, both providing grapes more acceptable to consumers than the control. Thus, it is possible to decrease irrigation amount by ~30 % of table grapes without adversely affecting berry physical quality.This work was supported by the projects (AGL2010-19201-C04-04) and (FP7-KBBE-2009-3-245159). M.R. Conesa acknowledges her FPU fellowship of the MICINN
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