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Threat Landscape and Good Practice Guide for Software Defined Networks/5G
5G represents the next major phase of mobile telecommunication systems and network architectures beyond the current 4G standards, aiming at extreme broadband and ultra-robust, low latency connectivity, to enable the programmable connectivity for the Internet of Everything2. Despite the significant debate on the technical specifications and the technological maturity of 5G, which are under discussion in various fora3, 5G is expected to affect positively and significantly several industry sectors ranging from ICT to industry sectors such as car and other manufacturing, health and agriculture in the period up to and beyond 2020. 5G will be driven by the influence of software on network functions, known as Software Defined Networking (SDN) and Network Function Virtualization (NFV). The key concept that underpins SDN is the logical centralization of network control functions by decoupling the control and packet forwarding functionality of the network. NFV complements this vision through the virtualization of these functionalities based on recent advances in general server and enterprise IT virtualization. Considering the technological maturity of the technologies that 5G can leverage on, SDN is the one that is moving faster from development to production. To realize the business potential of SDN/5G, a number of technical issues related to the design and operation of Software Defined Networks need to be addressed. Amongst them, SDN/5G security is one of the key issues, that needs to be addressed comprehensively in order to avoid missing the business opportunities arising from SDN/5G. In this report, we review threats and potential compromises related to the security of SDN/5G networks. More specifically, this report contains a review of the emerging threat landscape of 5G networks with particular focus on Software Defined Networking. It also considers security of NFV and radio network access. To provide a comprehensive account of the emerging threat SDN/5G landscape, this report has identified related network assets and the security threats, challenges and risks arising for these assets. Driven by the identified threats and risks, this report has also reviewed and identified existing security mechanisms and good practices for SDN/5G/NFV, and based on these it has analysed gaps and provided technical, policy and organizational recommendations for proactively enhancing the security of SDN/5G
Study of thymus and thymocytes in Bolivian preschool children during recovery from severe protein energy malnutrition
Réhabilitation immunonutritionnelle d'enfants atteints de malnutrition sévère
Le déficit immunitaire de l'enfant souffrant de malnutrition est connu de longue date mais rarement pris en compte dans le processus de récupération nutritionnelle. Le centre de réhabilitation immunonutritionnelle (CRIN) de Cochabamba (Bolivie) s'est donné comme objectif de restaurer les aspects clinico-nutritionnels et immunologiques lors du traitement d'enfants atteints de malnutrition sévère. Les enfants admis au CRIN sont recrutés parmi ceux qui, âgés de 6 mois à 6 ans, séjournent à l'hôpital materno-infantile. Durant les deux mois de séjour dans le service, ils bénéficient d'un traitement global dispensé par une équipe pluridisciplinaire composée de pédiatres, d'immunologistes, de nutritionnistes, de psychologues et de sociologues. La récupération nutritionnelle est basée sur un modèle diététique en quatre phases. Le suivi de ces enfants au niveau anthropométrique, immunologique (échographie du thymus et sous-populations lymphocytaires) et psychologique est assuré par l'équipe. Les études menées au CRIN ont montré : une atteinte spécifique de l'immunité à médiation cellulaire avec involution thymique et taux élevé de lymphocytes immatures ; un déphasage entre les vitesses de récupération clinico-nutritionnelle et immunologique, qui explique en grande partie les rechutes observées dans la plupart des centres de récupération nutritionnelle ; une possibilité d'accélerer la récupération immunitaire grâce à un supplément journalier en zinc afin qu'elle coïncide avec la récupération nutritionnelle et permette une sortie plus rapide de l'enfant sans risque de rechute. (Résumé d'auteur
Preliminary results from the STEPHI2009 campaign on the open cluster NGC 1817
We present preliminary observational results of the multi-site STEPHI
campaign on the cluster NGC 1817. The three observatories involved are San
Pedro Martir (Mexico), Xing Long (China) and the Observatorio del Teide (Spain)
- giving an ideal combination to maximise the duty cycle. The cluster has 12
known delta Scuti stars and at least two detached eclipsing binary systems.
This combination of characteristics is ideal for extracting information about
global parameters of the targets, which will in turn impose strict constraints
on the stellar models. From an initial comparison with stellar models using the
known fundamental parameters, and just the observed pulsation frequencies and
measured effective temperatures, it appears that a lower value of initial
helium mass fraction will most likely explain the observations of these stars.Comment: 4 pages, proceedings from HELAS IV meeting 2010, Lanzarot
Software Tool for Acausal Physical Modelling and Simulation
Modelling and simulation are key tools for analysis and design of systems and processes from almost any scientific or engineering discipline. Models of complex systems are typically built on acausal Differential-Algebraic Equations (DAE) and discrete events using Object-Oriented Modelling (OOM) languages, and some of their key concepts can be explained as symmetries. To obtain a computer executable version from the original model, several algorithms, based on bipartite symmetric graphs, must be applied for automatic equation generation, removing alias equations, computational causality assignment, equation sorting, discrete-event processing or index reduction. In this paper, an open source tool according to OOM paradigm and developed in MATLAB is introduced. It implements such algorithms adding an educational perspective about how they work, since the step by step results obtained after processing the model equations can be shown. The tool also allows to create models using its own OOM language and to simulate the final executable equation set. It was used by students in a modelling and simulation course of the Automatic Control and Industrial Electronics Engineering degree, showing a significant improvement in their understanding and learning of the abovementioned topics after their assessment
Escoliosis congénitas causadas por hemivertebras
Presentamos un estudio retrospectivo de 26 pacientes diagnosticados de escoliosis
congénitas causadas por hemivertebras, liemos analizado la evolución de las curvas según el tipo
de hemivértebra, su localización y el tratamiento recibido. Se han obtenido los peores resultados
en las niñas, cuando el diagnóstico se realizó después de los 10 años de edad, en las curvas localizadas
en la región toracolumbar, en las hemivértebras múltiples y, dentro de ellas, en las unilaterales
segmentadas no adyacentes y en los pacientes tratados ortopédicamente.A retrospective study of 26 patients with congenital scoliosis due to hemivertebra
was conducted. Curve progression was analysed regarding the type of hemivertebra, its localization,
and the applied treatment. The worst results were found in girls, in cases who were diagnosed
with more than to years of age, in thoraco-lumbar curves, in multiple hemivertebra, especially
in non-adjacent segmented unilateral hemivertebra and, finally, in patients treated with orthopaedic
methods
Multi-site observations of Delta Scuti stars 7 Aql and 8 Aql (a new Delta Scuti variable): The twelfth STEPHI campaign in 2003
We present an analysis of the pulsation behaviour of the Delta Scuti stars 7
Aql (HD 174532) and 8 Aql (HD 174589) -- a new variable star -- observed in the
framework of STEPHI XII campaign during 2003 June--July. 183 hours of high
precision photometry were acquired by using four-channel photometers at three
sites on three continents during 21 days. The light curves and amplitude
spectra were obtained following a classical scheme of multi-channel photometry.
Observations in different filters were also obtained and analyzed. Six and
three frequencies have been unambiguously detected above a 99% confidence level
in the range 0.090 mHz--0.300 mHz and 0.100 mHz-- 0.145 mHz in 7 Aql and 8 Aql
respectively. A comparison of observed and theoretical frequencies shows that 7
Aql and 8 Aql may oscillate with p modes of low radial orders, typical among
Delta Scuti stars. In terms of radial oscillations the range of 8 Aql goes from
n=1 to n=3 while for 7 Aql the range spans from n=4 to n=7. Non-radial
oscillations have to be present in both stars as well. The expected range of
excited modes according to a non adiabatic analysis goes from n=1 to n=6 in
both stars.Comment: 8 pages, 7 fugures, 5 tables, accepted for publication in
Astronomical Journa
Pulsational frequencies of the eclipsing delta-Scuti star HD 172189
The eclipsing delta-Scuti star HD 172189 is a probable member of the open
cluster IC 4756 and a promising candidate target for the CoRoT mission.
The detection of pulsation modes is the first step in the asteroseismological
study of the star. Further, the calculation of the orbital parameters of the
binary system allows us to make a dynamical determination of the mass of the
star, which works as an important constraint to test and calibrate the
asteroseismological models.
From a detailed frequency analysis of 210 hours of photometric data of HD
172189 obtained from the STEPHI XIII campaign we have identified six pulsation
frequencies with a confidence level of 99% and a seventh with a 65% confidence
level in the range between 100-300 uHz. In addiction, three eclipses were
observed during the campaign, allowing us to improve the determination of the
orbital period of the system.Comment: 6 pages, 7 figure
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