15 research outputs found

    VOSYSmonitor, a Low Latency Monitor Layer for Mixed-Criticality Systems on ARMv8-A

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    With the emergence of multicore embedded System on Chip (SoC), the integration of several applications with different levels of criticality on the same platform is becoming increasingly popular. These platforms, known as mixed-criticality systems, need to meet numerous requirements such as real-time constraints, Operating System (OS) scheduling, memory and OSes isolation. To construct mixed-criticality systems, various solutions, based on virtualization extensions, have been presented where OSes are contained in a Virtual Machine (VM) through the use of a hypervisor. However, such implementations usually lack hardware features to ensure a full isolation of other bus masters (e.g., Direct Memory Access (DMA) peripherals, Graphics Processing Unit (GPU)) between OSes. Furthermore on multicore implementation, one core is usually dedicated to one OS, causing CPU underutilization. To address these issues, this paper presents VOSYSmonitor, a multi-core software layer, which allows the co-execution of a safety-critical Real-Time Operating System (RTOS) and a non-critical General Purpose Operating System (GPOS) on the same hardware ARMv8-A platform. VOSYSmonitor main differentiation factors with the known solutions is the possibility for a processor to switch between secure and non-secure code execution at runtime. The partitioning is ensured by the ARM TrustZone technology, thus allowing to preserve the usage of virtualization features for the GPOS. VOSYSmonitor architecture will be detailed in this paper, while benchmarking its performance versus other known solutions

    VOSYSmonitor, a TrustZone-based Hypervisor for ISO 26262 Mixed-critical System

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    With the emergence of multicore embedded System on Chip (SoC), the integration of several applications with different levels of criticality on the same platform is becoming increasingly popular. These platforms, known as mixed-criticality systems, need to meet numerous requirements (e.g. real-time constraints, multiple Operating Systems (OS) scheduling, pro- viding temporal and spatial isolation). In this context Virtual Open Systems has developed VOSYSmonitor, a thin software layer, which allows the co-execution of a safety-critical and non- critical applications on a single ARM-based multi-core SoC. This software element has been developed according to the ISO 26262 standard. One of the key aspects of this standard is the control of random and systematic failures, including the ones induced by faulty or aging hardware. In the case of a software component, the means to detect anomalies on the hardware are limited and depend on choices of the manufacturer (i.e. implementation of Dual redundant Core Lock step (DCLS)). However, the software is able to check a part of these failures. It can be by either reading the conïŹguration registers of a peripheral, or checking the sanity of a memory region. The purpose of this paper is to showcase how a safety-related software element (e.g. VOSYSmonitor) can detect and recover from failures, while ensuring that the safety-related goals are still reached

    Malaria after international travel: a GeoSentinel analysis, 2003-2016.

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    BACKGROUND: More than 30,000 malaria cases are reported annually among international travellers. Despite improvements in malaria control, malaria continues to threaten travellers due to inaccurate perception of risk and sub-optimal pre-travel preparation. METHODS: Records with a confirmed malaria diagnosis after travel from January 2003 to July 2016 were obtained from GeoSentinel, a global surveillance network of travel and tropical medicine providers that monitors travel-related morbidity. Records were excluded if exposure country was missing or unascertainable or if there was a concomitant acute diagnosis unrelated to malaria. Records were analyzed to describe the demographic and clinical characteristics of international travellers with malaria. RESULTS: There were 5689 travellers included; 325 were children <18 years. More than half (53%) were visiting friends and relatives (VFRs). Most (83%) were exposed in sub-Saharan Africa. The median trip duration was 32 days (interquartile range 20-75); 53% did not have a pre-travel visit. More than half (62%) were hospitalized; children were hospitalized more frequently than adults (73 and 62%, respectively). Ninety-two per cent had a single Plasmodium species diagnosis, most frequently Plasmodium falciparum (4011; 76%). Travellers with P. falciparum were most frequently VFRs (60%). More than 40% of travellers with a trip duration ≀7 days had Plasmodium vivax. There were 444 (8%) travellers with severe malaria; 31 children had severe malaria. Twelve travellers died. CONCLUSION: Malaria remains a serious threat to international travellers. Efforts must focus on preventive strategies aimed on children and VFRs, and chemoprophylaxis access and preventive measure adherence should be emphasized

    Traveller exposures to animals: a GeoSentinel analysis

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    BACKGROUND Human coexistence with other animals can result in both intentional and unintentional contact with a variety of mammalian and non-mammalian species. International travellers are at risk for such encounters; travellers risk injury, infection and possibly death from domestic and wild animal bites, scratches, licks and other exposures. The aim of the present analysis was to understand the diversity and distribution of animal-related exposures among international travellers. METHODS Data from January 2007 through December 2018 from the GeoSentinel Surveillance Network were reviewed. Records were included if the exposure was non-migration travel with a diagnosis of an animal (dog, cat, monkey, snake or other) bite or other exposure (non-bite); records were excluded if the region of exposure was not ascertainable or if another, unrelated acute diagnosis was reported. RESULTS A total of 6470 animal exposures (bite or non-bite) were included. The majority (71%) occurred in Asia. Travellers to 167 countries had at least one report of an animal bite or non-bite exposure. The majority (76%) involved dogs, monkeys and cats, although a wide range of wild and domestic species were involved. Almost two-thirds (62.6%) of 4395 travellers with information available did not report a pretravel consultation with a healthcare provider. CONCLUSIONS Minimizing bites and other animal exposures requires education (particularly during pretravel consultations) and behavioral modification. These should be supplemented by the use of pre-exposure rabies vaccination for travellers to high-risk countries (especially to those with limited access to rabies immunoglobulin), as well as encouragement of timely (in-country) post-exposure prophylaxis for rabies and Macacine alphaherpesvirus 1 (herpesvirus B) when warranted

    BĂątards et bĂątardises dans l’Europe mĂ©diĂ©vale et moderne

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    Les auteurs ont cherchĂ© Ă  poser les jalons d’une histoire sociale et culturelle de la bĂątardise dans les sociĂ©tĂ©s europĂ©ennes du Moyen Âge et de l’époque moderne. La diversitĂ© des disciplines mobilisĂ©es (histoire, histoire du droit, linguistique, littĂ©rature, dĂ©mographie historique) permet de mettre en valeur la pluralitĂ© des approches d’un statut intrinsĂšquement complexe, d’une rĂ©alitĂ© sociale irrĂ©ductible Ă  un modĂšle unique, dont l’apprĂ©ciation par l’Église, la sociĂ©tĂ© ou la parentĂ© oscille entre exclusion et intĂ©gration, stigmatisation et rĂ©habilitation. Ils ont articulĂ© l’approche thĂ©orique de ce que le droit nous dit d’un statut pensĂ© comme outil de contrainte pour hiĂ©rarchiser les filiations et promouvoir l’institution matrimoniale, Ă  celle, pratique, de profils ou de destins particuliers. La bĂątardise renvoie Ă  une « macule de geniture » ou un defectus natalium qui stigmatise l’enfant (naturel, adultĂ©rin, ou sacrilĂšge) nĂ© d’un couple qui n’était pas uni en « loial mariage ». Les bĂątards sont exclus des ordres sacrĂ©s et de l’hĂ©ritage de leurs parents ; leur tĂ©moignage est irrecevable en justice ; de nombreux mĂ©tiers leur sont inaccessibles. L’« honnĂȘtetĂ© de leur conversation » peut toutefois permettre de motiver une demande de dispense auprĂšs du pape pour accĂ©der aux ordres majeurs ou une lĂ©gitimation auprĂšs des pouvoirs souverains pour hĂ©riter de leurs parents ou accĂ©der Ă  des offices. Pour les autres, thĂ©oriquement sans gens ni genus, quel destin se profile donc ? Une parentalitĂ© particuliĂšre s’exprime selon que l’enfant est accueilli dans une fratrie, dans la maison de son pĂšre, ou qu’il est abandonnĂ© aux institutions charitables qui se substituent au pĂšre charnel ; selon aussi que l’enfant naĂźt ou non dans la noblesse qui lui offre un temps certaines opportunitĂ©s d’ascension sociale. L’ambiguĂŻtĂ© du regard des sociĂ©tĂ©s anciennes sur ce statut se rĂ©vĂšle aussi dans la maniĂšre dont les littĂ©ratures mĂ©diĂ©vales et modernes ont pu mobiliser la figure du bĂątard, « monstre politique », incarnation d’une hybridation originelle qui permet de problĂ©matiser les normes sociales et politiques de leurs temps

    Cutaneous and mucocutaneous leishmaniasis in travellers and migrants: a 20-year GeoSentinel Surveillance Network analysis

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    BACKGROUND: Cutaneous leishmaniasis (CL) may be emerging among international travellers and migrants. Limited data exist on mucocutaneous leishmaniasis (MCL) in travellers. We describe the epidemiology of travel-associated CL and MCL among international travellers and immigrants over a 20-year period through descriptive analysis of GeoSentinel data. METHODS: Demographic and travel-related data on returned international travellers diagnosed with CL or MCL at a GeoSentinel Surveillance Network site between 1 September 1997 and 31 August 2017 were analysed. RESULTS: A total of 955 returned travellers or migrants were diagnosed with travel-acquired CL (n = 916) or MCL during the study period, of whom 10% (n = 97) were migrants. For the 858 non-migrant travellers, common source countries were Bolivia (n = 156, 18.2%) and Costa Rica (n = 97, 11.3%), while for migrants, they were Syria (n = 34, 35%) and Afghanistan (n = 22, 22.7%). A total of 99 travellers (10%) acquired their disease on trips of ≀ 2 weeks. Of 274 cases for which species identification was available, Leishmania Viannia braziliensis was the most well-represented strain (n = 117, 42.7%), followed by L. major (n = 40, 14.6%) and L. V. panamensis (n = 38, 13.9%). Forty cases of MCL occurred, most commonly in tourists (n = 29, 72.5%) and from Bolivia (n = 18, 45%). A total of 10% of MCL cases were acquired in the Old World. CONCLUSIONS: Among GeoSentinel reporting sites, CL is predominantly a disease of tourists travelling mostly to countries in Central and South America such as Bolivia where risk of acquiring L. V. braziliensis and subsequent MCL is high. The finding that some travellers acquired leishmaniasis on trips of short duration challenges the common notion that CL is a disease of prolonged travel. Migrants from areas of conflict and political instability, such as Afghanistan and Syria, were well represented, suggesting that as mass migration of refugees continues, CL will be increasingly encountered in intake countries
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