1,037 research outputs found

    Automated Network Service Scaling in NFV: Concepts, Mechanisms and Scaling Workflow

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    Next-generation systems are anticipated to be digital platforms supporting innovative services with rapidly changing traffic patterns. To cope with this dynamicity in a cost-efficient manner, operators need advanced service management capabilities such as those provided by NFV. NFV enables operators to scale network services with higher granularity and agility than today. For this end, automation is key. In search of this automation, the European Telecommunications Standards Institute (ETSI) has defined a reference NFV framework that make use of model-driven templates called Network Service Descriptors (NSDs) to operate network services through their lifecycle. For the scaling operation, an NSD defines a discrete set of instantiation levels among which a network service instance can be resized throughout its lifecycle. Thus, the design of these levels is key for ensuring an effective scaling. In this article, we provide an overview of the automation of the network service scaling operation in NFV, addressing the options and boundaries introduced by ETSI normative specifications. We start by providing a description of the NSD structure, focusing on how instantiation levels are constructed. For illustrative purposes, we propose an NSD for a representative NS. This NSD includes different instantiation levels that enable different ways to automatically scale this NS. Then, we show the different scaling procedures the NFV framework has available, and how it may automate their triggering. Finally, we propose an ETSI-compliant workflow to describe in detail a representative scaling procedure. This workflow clarifies the interactions and information exchanges between the functional blocks in the NFV framework when performing the scaling operation.Comment: This work has been accepted for publication in the IEEE Communications Magazin

    Alterations in Lipid Levels of Mitochondrial Membranes Induced by Amyloid-β: A Protective Role of Melatonin

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    Alzheimer pathogenesis involves mitochondrial dysfunction, which is closely related to amyloid-β (Aβ) generation, abnormal tau phosphorylation, oxidative stress, and apoptosis. Alterations in membranal components, including cholesterol and fatty acids, their characteristics, disposition, and distribution along the membranes, have been studied as evidence of cell membrane alterations in AD brain. The majority of these studies have been focused on the cytoplasmic membrane; meanwhile the mitochondrial membranes have been less explored. In this work, we studied lipids and mitochondrial membranes in vivo, following intracerebral injection of fibrillar amyloid-β (Aβ). The purpose was to determine how Aβ may be responsible for beginning of a vicious cycle where oxidative stress and alterations in cholesterol, lipids and fatty acids, feed back on each other to cause mitochondrial dysfunction. We observed changes in mitochondrial membrane lipids, and fatty acids, following intracerebral injection of fibrillar Aβ in aged Wistar rats. Melatonin, a well-known antioxidant and neuroimmunomodulator indoleamine, reversed some of these alterations and protected mitochondrial membranes from obvious damage. Additionally, melatonin increased the levels of linolenic and n-3 eicosapentaenoic acid, in the same site where amyloid β was injected, favoring an endogenous anti-inflammatory pathway

    Safety and immediate humoral response of COVID-19 vaccines in chronic kidney disease patients:the SENCOVAC study

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    BACKGROUND: Chronic kidney disease (CKD) patients are at high-risk for severe Covid-19. The multicentric, observational and prospective SENCOVAC study aims to describe the humoral response and safety of SARS-CoV-2 vaccines in CKD patients. Safety and immediate humoral response results are reported here. METHODS: Four cohorts of patients were included: kidney transplant (KT) recipients, haemodialysis (HD), peritoneal dialysis (PD) and non-dialysis CKD patients from 50 Spanish centres. Adverse events after vaccine doses were recorded. At baseline and on day 28 after the last vaccine dose, anti-Spike antibodies were measured and compared between cohorts. Factors associated with development of anti-Spike antibodies were analyzed. RESULTS: 1746 participants were recruited: 1116 HD, 171 PD, 176 non-dialysis CKD patients and 283 KT recipients. Most patients (98%) received mRNA vaccines. At least one vaccine reaction developed after the first dose in 763 (53.5%) and after the second dose in 741 (54.5%) of patients. Anti-Spike antibodies were measured in the first 301 patients. At 28 days, 95% of patients had developed antibodies: 79% of KT, 98% of HD, 99% of PD and 100% of non-dialysis CKD patients (p<0.001). In a multivariate adjusted analysis, absence of an antibody response was independently associated to KT (OR 20.56, p = 0.001) and to BNT162b2 vaccine (OR 6.03, p = 0.023). CONCLUSION: The rate of anti-Spike antibody development after vaccination in KT patients was low but in other CKD patients it approached 100%; suggesting that KT patients require persistent isolation measures and booster doses of a Covid-19 vaccine. Potential differences between Covid-19 vaccines should be explored in prospective controlled studies

    Allelic Variation of MYB10 Is the Major Force Controlling Natural Variation in Skin and Flesh Color in Strawberry (Fragaria spp.) Fruit

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    Independent mutations in the transcription factor MYB10 cause most of the anthocyanin variation observed in diploid woodland strawberry (Fragaria vesca) and octoploid cultivated strawberry (Fragaria x ananassa). The fruits of diploid and octoploid strawberry (Fragaria spp) show substantial natural variation in color due to distinct anthocyanin accumulation and distribution patterns. Anthocyanin biosynthesis is controlled by a clade of R2R3 MYB transcription factors, among which MYB10 is the main activator in strawberry fruit. Here, we show that mutations in MYB10 cause most of the variation in anthocyanin accumulation and distribution observed in diploid woodland strawberry (F. vesca) and octoploid cultivated strawberry (F. xananassa). Using a mapping-by-sequencing approach, we identified a gypsy-transposon in MYB10 that truncates the protein and knocks out anthocyanin biosynthesis in a white-fruited F. vesca ecotype. Two additional loss-of-function mutations in MYB10 were identified among geographically diverse white-fruited F. vesca ecotypes. Genetic and transcriptomic analyses of octoploid Fragaria spp revealed that FaMYB10-2, one of three MYB10 homoeologs identified, regulates anthocyanin biosynthesis in developing fruit. Furthermore, independent mutations in MYB10-2 are the underlying cause of natural variation in fruit skin and flesh color in octoploid strawberry. We identified a CACTA-like transposon (FaEnSpm-2) insertion in the MYB10-2 promoter of red-fleshed accessions that was associated with enhanced expression. Our findings suggest that cis-regulatory elements in FaEnSpm-2 are responsible for enhanced MYB10-2 expression and anthocyanin biosynthesis in strawberry fruit flesh.Peer reviewe

    Servicio centralizado de proyección de material docente

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    [ES] En los últimos años las tecnologías TIC se han ido incorporando en los diferentes ámbitos de la enseñanza, desde las pizarras electrónicas para las clases magistrales hasta el uso de tabletas para la visualización de libros docentes en formato electrónico. De hecho, resulta cada vez más frecuente que los docentes empleen sus portátiles para presentar su material en formato de transparencias. No obstante, esto implica que los profesores deben llevar sus portátiles al aula y conectarlos a través de un cable, sea VGA o HDMI, al proyector. Esto resta movilidad al profesor, anclado a través del cable al proyector, además de requerir que disponga de un portátil que ha de llevar al aula. Dado que, en la actualidad, casi la totalidad de la población dispone de móviles inteligentes, este artículo presenta la solución propuesta en un proyecto de innovación docente desarrollado (PID 14-61) en la Universidad de Granada. En éste, se propone una solución en la que el profesor sólo deberá llevar su móvil (o alternativamente una tableta o un portátil) al aula. El material docente será subido a un servidor central desde su despacho, y la visualización en el proyector será controlada a través del móvil usando una interfaz muy amigable y sencillo.El presente trabajo ha sido financiado a traves del Programa de Innovacion y Buenas Prácticas Docentes del Secretariado de Innovacion Docente de la Universidad de Granada, Proyecto de Innovacion Docente 14-61 ”Servicio de Proyeccion de Material Docente”, dentro de la acción 1 (innovacion en la gestión on-line de los procesos de ensenanza-aprendizaje). Parte del presente trabajo ha sido ˜ desarrollado por los alumnos D. Juan Ramon Gutiérrez Martínez, D. Daniel Alvarez González y D. David Gallardo Jimenez, siendo estos dos últimos becarios del citado PID.Navarro Ortiz, J.; Sendra, S.; Ameigeiras, P.; Torre, ADL.; Garcia, L.; Gomez, A.; Lopez-Soler, J.... (2018). Servicio centralizado de proyección de material docente. En XIII Jornadas de Ingeniería telemática (JITEL 2017). Libro de actas. Editorial Universitat Politècnica de València. 330-336. https://doi.org/10.4995/JITEL2017.2017.6508OCS33033

    Emergence potential of sylvatic dengue virus type 4 in the urban transmission cycle is restrained by vaccination and homotypic immunity

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    Sylvatic dengue viruses (DENV) are both evolutionarily and ecologically distinct from human DENV and are maintained in an enzootic transmission cycle. Evidence of sylvatic human infections from West Africa and Southeast Asia suggests that sylvatic DENV come into regular contact with humans. Thus, this potential of emergence into the human transmission cycle could limit the potential for eradicating this cycle with vaccines currently in late stages of development. We assessed the likelihood of sylvatic DENV-4 emergence in the face of natural immunity to current human strains and vaccination with two DENV-4 vaccine candidates. Our data indicate homotypic neutralization of sylvatic and human DENV-4 strains by human primary convalescent and vaccinee sera but limited heterotypic immunity. These results suggest that emergence of sylvatic strains into the human cycle would be limited by homotypic immunity mediated by virus neutralizing antibodies produced by natural infection or vaccination

    Emergence potential of sylvatic dengue virus type 4 in the urban transmission cycle is restrained by vaccination and homotypic immunity

    Get PDF
    Sylvatic dengue viruses (DENV) are both evolutionarily and ecologically distinct from human DENV and are maintained in an enzootic transmission cycle. Evidence of sylvatic human infections from West Africa and Southeast Asia suggests that sylvatic DENV come into regular contact with humans. Thus, this potential of emergence into the human transmission cycle could limit the potential for eradicating this cycle with vaccines currently in late stages of development. We assessed the likelihood of sylvatic DENV-4 emergence in the face of natural immunity to current human strains and vaccination with two DENV-4 vaccine candidates. Our data indicate homotypic neutralization of sylvatic and human DENV-4 strains by human primary convalescent and vaccinee sera but limited heterotypic immunity. These results suggest that emergence of sylvatic strains into the human cycle would be limited by homotypic immunity mediated by virus neutralizing antibodies produced by natural infection or vaccination
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