SDN-based control and orchestration of optical data centre networks

The use of the Internet is linked with the constant technological change that the world is suffering nowadays, which is responsible for the important need to update the infrastructure of current data centers. The amount of traffic that is moving in data centers has increased significantly in the past few years, so a better alternative for them should be studied, as the use of Ethernet or InfiniBand is no longer appropriate in terms of scalability and flexibility. Optical technology is one possible solution for it, as it provides a big bandwidth, low latency and an overall better performance. However, the physical resources that form a data center should be managed in an efficient way. To perform an optimum use of them, the new concept of virtual data center appeared, where the orchestration of the resources is done with the aim of offering to a cloud infrastructure to a third party. In this context, OpenStack has become one of the most popular open source platforms when building public or private clouds, based on three important aspects: compute, storage and network. But the flexibility of these cloud infrastructures is attached to being scalable or dynamic. In this case, Software Definiton Network (SDN) and Network Function Virtualization (NFV) play an important role in data centers, as they allow to build complex network capabilities on demand. In this project, we experimentally demonstrate the programmable OPsquare data center network empowered by an SDN control plane. The implementation is based on monitoring the real-time statistics of the network, so some actions such as network slices provisioning and reconfiguration, packet priority class assignment or dynamic load balancing operations can be done in order to achieve the required Quality of Service level. This project is a cooperation between TU/e (Eindhoven University of Technology, The Netherlands) and UPC (Universitat Politècnica de Catalunya, Barcelona)

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

SDN-based control and orchestration of optical data centre networks

The use of the Internet is linked with the constant technological change that the world is suffering nowadays, which is responsible for the important need to update the infrastructure of current data centers. The amount of traffic that is moving in data centers has increased significantly in the past few years, so a better alternative for them should be studied, as the use of Ethernet or InfiniBand is no longer appropriate in terms of scalability and flexibility. Optical technology is one possible solution for it, as it provides a big bandwidth, low latency and an overall better performance. However, the physical resources that form a data center should be managed in an efficient way. To perform an optimum use of them, the new concept of virtual data center appeared, where the orchestration of the resources is done with the aim of offering to a cloud infrastructure to a third party. In this context, OpenStack has become one of the most popular open source platforms when building public or private clouds, based on three important aspects: compute, storage and network. But the flexibility of these cloud infrastructures is attached to being scalable or dynamic. In this case, Software Definiton Network (SDN) and Network Function Virtualization (NFV) play an important role in data centers, as they allow to build complex network capabilities on demand. In this project, we experimentally demonstrate the programmable OPsquare data center network empowered by an SDN control plane. The implementation is based on monitoring the real-time statistics of the network, so some actions such as network slices provisioning and reconfiguration, packet priority class assignment or dynamic load balancing operations can be done in order to achieve the required Quality of Service level. This project is a cooperation between TU/e (Eindhoven University of Technology, The Netherlands) and UPC (Universitat Politècnica de Catalunya, Barcelona)

SDN-based control and orchestration of optical data centre networks

The use of the Internet is linked with the constant technological change that the world is suffering nowadays, which is responsible for the important need to update the infrastructure of current data centers. The amount of traffic that is moving in data centers has increased significantly in the past few years, so a better alternative for them should be studied, as the use of Ethernet or InfiniBand is no longer appropriate in terms of scalability and flexibility. Optical technology is one possible solution for it, as it provides a big bandwidth, low latency and an overall better performance. However, the physical resources that form a data center should be managed in an efficient way. To perform an optimum use of them, the new concept of virtual data center appeared, where the orchestration of the resources is done with the aim of offering to a cloud infrastructure to a third party. In this context, OpenStack has become one of the most popular open source platforms when building public or private clouds, based on three important aspects: compute, storage and network. But the flexibility of these cloud infrastructures is attached to being scalable or dynamic. In this case, Software Definiton Network (SDN) and Network Function Virtualization (NFV) play an important role in data centers, as they allow to build complex network capabilities on demand. In this project, we experimentally demonstrate the programmable OPsquare data center network empowered by an SDN control plane. The implementation is based on monitoring the real-time statistics of the network, so some actions such as network slices provisioning and reconfiguration, packet priority class assignment or dynamic load balancing operations can be done in order to achieve the required Quality of Service level. This project is a cooperation between TU/e (Eindhoven University of Technology, The Netherlands) and UPC (Universitat Politècnica de Catalunya, Barcelona)

X chromosome inactivation does not necessarily determine the severity of the phenotype in Rett syndrome patients

WOS: 000481590200024PubMed ID: 31427717Rett syndrome (RTT) is a severe neurological disorder usually caused by mutations in the MECP2 gene. Since the MECP2 gene is located on the X chromosome, X chromosome inactivation (XCI) could play a role in the wide range of phenotypic variation of RTT patients; however, classical methylation-based protocols to evaluate XCI could not determine whether the preferentially inactivated X chromosome carried the mutant or the wild-type allele. Therefore, we developed an allele-specific methylation-based assay to evaluate methylation at the loci of several recurrent MECP2 mutations. We analyzed the XCI patterns in the blood of 174 RTT patients, but we did not find a clear correlation between XCI and the clinical presentation. We also compared XCI in blood and brain cortex samples of two patients and found differences between XCI patterns in these tissues. However, RTT mainly being a neurological disease complicates the establishment of a correlation between the XCI in blood and the clinical presentation of the patients. Furthermore, we analyzed MECP2 transcript levels and found differences from the expected levels according to XCI. Many factors other than XCI could affect the RTT phenotype, which in combination could influence the clinical presentation of RTT patients to a greater extent than slight variations in the XCI pattern.Spanish Ministry of Health (Instituto de Salud Carlos III/FEDER) [PI15/01159]; Crowdfunding program PRECIPITA, from the Spanish Ministry of Health (Fundacion Espanola para la Ciencia y la Tecnologia); Catalan Association for Rett Syndrome; Fondobiorett; Mi Princesa RettWe thank all patients and their families who contributed to this study. The work was supported by grants from the Spanish Ministry of Health (Instituto de Salud Carlos III/FEDER, PI15/01159); Crowdfunding program PRECIPITA, from the Spanish Ministry of Health (Fundacion Espanola para la Ciencia y la Tecnologia); the Catalan Association for Rett Syndrome; Fondobiorett and Mi Princesa Rett