12 research outputs found

    Open Source Solutions for Building IaaS Clouds

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    Cloud Computing is not only a pool of resources and services offered through the internet, but also a technology solution that allows optimization of resources use, costs minimization and energy consumption reduction. Enterprises moving towards cloud technologies have to choose between public cloud services, such as: Amazon Web Services, Microsoft Cloud and Google Cloud services, or private self built clouds. While the firsts are offered with affordable fees, the others provide more privacy and control. In this context, many open source softwares approach the buiding of private, public or hybrid clouds depending on the users need and on the available capabilities. To choose among the different open source solutions, an analysis is necessary in order to select the most suitable according with the enterprise’s goals and requirements. In this paper, we present a depth study and comparison of five open source frameworks that are gaining more attention recently and growing fast: CloudStack, OpenStack, Eucalyptus, OpenNebula and Nimbus. We present their architectures and discuss different properties, features, useful information and our own insights on these frameworks

    Green Approach for Joint Management of Geo-Distributed Data Centers and Interconnection Networks

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    Every time an Internet user downloads a video, shares a picture, or sends an email, his/her device addresses a data center and often several of them. These complex systems feed the web and all Internet applications with their computing power and information storage, but they are very energy hungry. The energy consumed by Information and Communication Technology (ICT) infrastructures is currently more than 4\% of the worldwide consumption and it is expected to double in the next few years. Data centers and communication networks are responsible for a large portion of the ICT energy consumption and this has stimulated in the last years a research effort to reduce or mitigate their environmental impact. Most of the approaches proposed tackle the problem by separately optimizing the power consumption of the servers in data centers and of the network. However, the Cloud computing infrastructure of most providers, which includes traditional telcos that are extending their offer, is rapidly evolving toward geographically distributed data centers strongly integrated with the network interconnecting them. Distributed data centers do not only bring services closer to users with better quality, but also provide opportunities to improve energy efficiency exploiting the variation of prices in different time zones, the locally generated green energy, and the storage systems that are becoming popular in energy networks. In this paper, we propose an energy aware joint management framework for geo-distributed data centers and their interconnection network. The model is based on virtual machine migration and formulated using mixed integer linear programming. It can be solved using state-of-the art solvers such as CPLEX in reasonable time. The proposed approach covers various aspects of Cloud computing systems. Alongside, it jointly manages the use of green and brown energies using energy storage technologies. The obtained results show that significant energy cost savings can be achieved compared to a baseline strategy, in which data centers do not collaborate to reduce energy and do not use the power coming from renewable resources

    Fetal outcome in emergency versus elective cesarean sections at Souissi Maternity Hospital, Rabat, Morocco

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    Introduction: Perinatal mortality rates have come down in cesarean sections, but fetal morbidity is still high in comparison to vaginal delivery and the complications are more commonly seen in emergency than in elective cesarean sections. The objective of the study was to compare the fetal outcome and the indications in elective versus emergency cesarean section performed in a tertiary maternity hospital. Methods: This comparative cross-sectional prospective study of all the cases undergoing elective and emergency cesarean section for any indication at Souissi maternity hospital of Rabat, Morocco, was carried from January 1, to February 28, 2014. Data were analyzed with emphasis on fetal outcome and cesarean sections indications. Mothers who had definite antenatal complications that would adversely affect fetal outcome were excluded from the study. Results: There was 588 (17.83%) cesarean sections among 3297 births of which emergency cesarean section accounted for 446 (75.85%) and elective cesarean section for 142 cases (24.15%). Of the various factors analyzed in relation to the two types of cesarean sections, statistically significant associations were found between emergency cesarean section and younger mothers (P < 0.001), maternal illiteracy (P = 0.049), primiparity (P = 0.005), insufficient prenatal care (P < 0.001), referral from other institution for pregnancy complications or delivery (P < 0.001), cesarean section performed under general anesthesia (P < 0.001), lower birth weight (P < 0.016), neonatal morbidity and early mortality (P < 0.001), and admission in neonatal intensive care unit (P = 0.024). The commonest indication of emergency cesarean section was fetal distress (30.49%), while the most frequent indication in elective cesarean section was previous cesarean delivery (47.18%). Conclusion: The overall fetal complications rate was higher in emergency cesarean section than in elective cesarean section. Early recognition and referral of mothers who are likely to undergo cesarean section may reduce the incidence of emergency cesarean sections and thus decrease fetal complications.Pan African Medical Journal 2016; 2

    The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

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    INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

    Effective management of green Cloud data centers using energy storage technologies

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    Severe neonatal cytomegalovirus infection: about a case

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    Maternofoetal infection with Cytomegalovirus (CMV) is the most common congenital infection and a leading cause of mental retardation and sensori-neural hearing loss. Population-based studies indicate that at least 0.5% of all infants born alive have CMV of whom approximately 10% have clinically evident symptomsat birth. The Justification of systematic screening for foetal CMV infection is still controversial and is not recommended in most developed countries. This is mainly justified by the paucity of antenatal prognostic factors and the lack of established intrauterine treatment when foetal infection has been diagnosed. In case of congenital CMV infection, infants can be symptomatic or asymptomatic at birth. Mortality for such infants can reach 30%, and survivors can have mental retardation, sensorineural hearing loss, chorioretinitis, and other significant medical problems. A newborn symptomatic is defined by the existence of clinical and / or biological signs and / or neonatal imaging, the most frequent clinical signs are: hepatosplenomegaly (60%), microcephaly (53%), jaundice (67%), petechiae (76%), at least one neurological abnormality (68%). The frequency of biological abnormalities is as follows: increase in transaminases (83%), thrombocytopenia (77%), hyperbilirubinemia (69%), haemolysis (51%), hyperproteinorrachy (46%). The abnormalities of neonatal imaging are present in 70% of symptomatic newborns; intracerebral calcifications are the most frequent abnormalities. We report a case of newborn who presented a congenital infection by CMV, evoked on the intrauterine growth retardation, organs of the reticulo endothelial and haematological system were reached while nervous system was spared, and CMV PCR was very positive. indicating an antiviral treatment for 6 weeks based on ganciclovir.Keywords: Cytomegalovirus, congenital infection, petechiae, intrauterine growth retardation, ganciclovi

    Open stack and cloud stack: Open source solutions for building public and private clouds

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    Cloud computing is continuously growing as a prominent technology for enterprises. While several giant public cloud providers, such as Amazon, Microsoft, IBM, Google are competing to extend their market, there is still a large number of organizations asking higher level of privacy and control over cloud solutions. Therefore, the need to have private cloud solutions is obvious. To overcome this need there are several on-going open source software frameworks for building public and private clouds. Among them, OpenStack and CloudStack are growing at fast pace and gaining more attention. An analysis on these software stacks is necessary in order to choose the most suitable solution that matches an enterprise’s requirements. This paper main contribution is an in depth study and comparison of the cloud properties of these two open source frameworks, providing useful information on open source cloud solutions that are not available elsewhere

    Epidémiologie et facteurs de risque des anomalies de fermeture du tube neural: données marocaines

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    Introduction: les anomalies de fermeture du tube neural sont des défauts congénitaux de la formation du système nerveux central. L'incidence varie entre 3 et 40 cas pour 10000 dans le monde. Il existe des facteurs de risque de survenue de cette affection. La prévention reste un élément important dans la prise en charge. L'objectif de ceete étude est d'étudier les paramètres sociodémographiques, maternels, obstétricaux et néonatals des anomalies de fermeture du tube neural et analyser les facteurs de risque responsables dans notre contexte. Méthodes: étude prospective cas-témoin sur 4 ans. Ont été recrutés tous les cas portant une malformation du tube neural isolée ou associée à d'autres malformations. Les données maternelles, obstétricales et néonatales ont été enregistrées. L'analyse statistique était réalisée par le biais d'un logiciel de statistiques SPSS version 17.0 pour Windows. Résultats: soixante huit cas ont été inclus. Quatre-vingts cinq pour cent des malformations étaient isolées. L'anencéphalie était l'anomalie la plus retrouvée (67 %). L'âge maternel moyen était 31,03±7,50 ans. La consanguinité parentale était notée dans 9 cas. Un niveau socio-économique bas et un non suivi des grossesses ont été rapportés dans 29 % des cas. L'étude a retrouvé des antécédents de mort-nés et de morts néonatales dans 4 % des cas. La consommation de Fenugrec était significativement associée aux malformations du tube neural et a été retrouvée dans 8 cas contre 1 cas dans le groupe sain. La voie haute d'accouchement était utilisée dans 29 % des cas. L'âge gestationnel moyen était de 35,55±4,16 semaines d'aménorrhée. Il n'y avait pas de prédominance de sexe. On avait noté une relation significative entre les malformations du tube neural et l'avènement d'une asphyxie périnatale, 15 cas présentaient un apgar à 0 à la première minute et 12 cas un apgar inférieur à 7 à la cinquième minute. Conclusion: le bas niveau socio-économique, le non suivi des grossesses et la consommation maternelle de fenugrec en période gestationnelle étaient des facteurs prédictifs de développement d'anomalies du tube neural dans notre contexte.The Pan African Medical Journal 2015;2

    Parotidite aigue néonatale suppurative: à propos de trois cas cliniques avec revue de la littérature

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    Cet article fait mention de trois cas de parotidite bactérienne néonatale observés pendant une période de sept mois. Ce diagnostic est souvent clinique: on retrouve classiquement hyperthermie, tuméfaction, érythème, chaleur ainsi que sensibilité locale et écoulement purulent au niveau du canal de Sténon lors du massage de la parotide. Le diagnostic clinique est confirmé par échographie et culture de la sécrétion parotidienne purulente. Elles sont le plus souvent d’origine nosocomiale, favorisées par la prématurité et la déshydratation. Traitées précocement, leur évolution est favorable. Les risques liés à l’âge doivent faire débuter une antibiothérapie empirique puis fonction de l'examen direct du pus extrait du canal de Sténon. On isole le plus communément le Staphylocoque aureus; le Streptocoque Viridans et les germes anaérobies. Les parotidites aigues sont très rares en période néonatale: moins de 50 cas ont été rapportés dans la littérature. Nous rapportons trois observations assez particulières. Le diagnostic avait été suspecté sur les signes inflammatoires locaux.The Pan African Medical Journal. 2016;2
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